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Sample records for human ocular cells

  1. Sex steroid hormone metabolism takes place in human ocular cells.

    PubMed

    Coca-Prados, Miguel; Ghosh, Sikha; Wang, Yugang; Escribano, Julio; Herrala, Annakaisa; Vihko, Pirkko

    2003-08-01

    Steroids are potentially important mediators in the pathophysiology of ocular diseases. In this study, we report on the gene expression in the human eye of a group of enzymes, the 17beta-hydroxysteroid dehydrogenases (17HSDs), involved in the biosynthesis and inactivation of sex steroid hormones. In the eye, the ciliary epithelium, a neuroendocrine secretory epithelium, co-expresses the highest levels of 17HSD2 and 5 mRNAs, and in lesser level 17HSD7 mRNA. The regulation of gene expression of these enzymes was investigated in vitro in cell lines, ODM-C4 and chronic open glaucoma (GCE), used as cell models of the human ciliary epithelium. The estrogen, 17beta-estradiol (10(-7) M) and androgen agonist, R1881 (10(-8) M) elicited in ODM-C4 and GCE cells over a 24 h time course a robust up-regulation of 17HSD7 mRNA expression. 17HSD2 was up-regulated by estradiol in ODM-C4 cells, but not in GCE cells. Under steady-state conditions, ODM-C4 cells exhibited a predominant 17HSD2 oxidative enzymatic activity. In contrast, 17HSD2 activity was low or absent in GCE cells. Our collective data suggest that cultured human ciliary epithelial cells are able to metabolize estrogen, androgen and progesterone, and that 17HSD2 and 7 in these cells are sex steroid hormone-responsive genes and 17HSD7 is responsible to keep on intra/paracrine estrogenic milieu.

  2. Generation of Human Corneal Endothelial Cells via In Vitro Ocular Lineage Restriction of Pluripotent Stem Cells

    PubMed Central

    Zhao, Jiagang J.; Afshari, Natalie A.

    2016-01-01

    Purpose We generate a renewable supply of corneal endothelial cells (CEC) from human pluripotent stem cells (PSCs) under defined culture conditions. Methods Corneal endothelial cell induction was driven by small molecules in a stepwise fashion of lineage specification. During the initial phase, PSC fate was restricted to the eye field-like state and became eye field stem cells (EFSCs). In the second phase, PSC-derived EFSCs were further directed toward either neural crest lineage or retinal lineage. The CECs were directly induced from ocular neural crest stem cells (NCSCs) by suppressing TGF-β and ROCK signaling. Results Under chemically defined conditions, PSCs were massively converted into EFSCs and subsequently NCSCs. Eye field cell identity was characterized by the expression of key fate restriction factors for early eye field cells, such as PAX6, LHX2, and VSX2. The induction of ocular NCSCs was initiated by promoting WNT signaling in EFSCs. Within 2 weeks of induction, the majority of cells expressed the typical neural crest markers p75NTR and HNK-1. Eye field stem cell-derived NCSCs can be propagated and cryopreserved. Subsequently, a CEC monolayer was induced from adherent NCSCs in the presence of small molecular inhibitors to suppress TGF-β and ROCK signaling. The polygon-shaped CEC-like cells became visible after a week in culture. The NCSC-derived CECs expressed typical CEC markers, such as N-Cadherin and Na+/K+-ATPase. Conclusions A novel small molecule-based approach was developed to derive human CECs from PSCs via ocular lineage specification. Moreover, EFSC-derived NCSCs could serve as an immediate source cell for rapid CEC induction in vitro. PMID:28002562

  3. Intraocular caspofungin: in vitro safety profile for human ocular cells.

    PubMed

    Kernt, M; Kampik, A

    2011-07-01

    Endogenous Candida endophthalmitis is sight-threatening, difficult to treat and sometimes leads to loss of the eye. Only a few therapeutic agents are available for its treatment. Caspofungin is the first of a new class of antifungal drugs (echinocandins) with a high activity against Candida species, the most common pathogens found in endogenous endophthalmitis. This study investigates the safety profile of caspofungin for intraocular application in a cell-culture model. Endothelial toxicity of caspofungin was evaluated in cultured human corneas. Possible toxic effects of caspofungin (5-300 μg ml(-1)) in corneal endothelial cells (CEC), primary human trabecular meshwork cells (TMC) and primary human retinal pigment epithelium (RPE) cells were evaluated after 24 h and under conditions of inflammatory stress by treatment with tumour necrosis factor-alpha (TNF-α), lipopolysaccharides (LPS) or interleukin-6 (IL-6) and hydrogen peroxide (H(2)O(2)). Toxicity was evaluated by tetrazolium dye-reduction assay; cell viability was quantified by a microscopic live-dead assay. No corneal endothelial toxicity could be detected after 30 days of treatment with 75 μg ml(-1) of caspofungin. Concentrations up to 75 μg ml(-1) had no influence on CEC, TMC or RPE cell proliferation, or on cell viability when administered for 24 h. Exposure to H(2)O(2) did not increase cellular toxicity of caspofungin at concentrations of 5-50 μg ml(-1). After preincubation with TNF-α, LPS or IL-6 for 24 h followed by treatment with caspofungin for 24 h, no significant decrease in cell proliferation or viability was observed. This study showed no significant toxicity for caspofungin on CEC, TMC or RPE cells, or human corneal endothelium when administered in therapeutic concentrations up to 50 μg ml(-1).

  4. Intracameral voriconazole: in vitro safety for human ocular cells.

    PubMed

    Kernt, M; Kampik, A

    2009-04-28

    Fungal keratitis is a sight-threatening infection of the cornea. It sometimes leads to loss of the eye. Despite an expanding range of fungal pathogens, there are only few therapeutic agents for its treatment available. Voriconazole is a second-generation synthetic triazole with a broad action against yeasts and molds. The current study investigates the safety of voriconazole for intracameral application in a cell culture model. Endothelial toxicity of voriconazole was evaluated in cultured human corneas. Possible toxic effects of voriconazole (10 microg /mL-10mg/mL) in corneal endothelial cells (CEC), primary human trabecular meshwork cells (TMC), and primary human retinal pigment epithelium (RPE) cells were evaluated after 24h and under conditions of inflammatory stress by treatment with tumor-necrosis-factor alpha (TNF-alpha), lipopolysaccharides (LPS), or interleukin-6 (IL-6) and hydrogen peroxide. Toxicity was evaluated by tetrazolium dye-reduction assay, and cell viability was quantified by a microscopic live-dead assay. No corneal endothelial toxicity could be detected after 30 days of treatment with 250 microg /mL of voriconazole. Concentrations up to 1mg/mL had no influence on CEC, TMC, or RPE cell proliferation, or on cell viability when administered for 24h. Hydrogen peroxide exposure did not increase cellular toxicity of voriconazole at concentrations from 10 to 250 microg /mL. After preincubation with TNF-alpha, LPS, or IL-6 for 24h and subsequent voriconazole treatment for 24h, no significant decrease in proliferation or viability was observed. This study showed no significant toxicity for voriconazole on CEC, TMC, RPE cells, or human corneal endothelium when administered in therapeutic concentrations up to 250 microg /mL.

  5. Human ocular anatomy.

    PubMed

    Kels, Barry D; Grzybowski, Andrzej; Grant-Kels, Jane M

    2015-01-01

    We review the normal anatomy of the human globe, eyelids, and lacrimal system. This contribution explores both the form and function of numerous anatomic features of the human ocular system, which are vital to a comprehensive understanding of the pathophysiology of many oculocutaneous diseases. The review concludes with a reference glossary of selective ophthalmologic terms that are relevant to a thorough understanding of many oculocutaneous disease processes.

  6. Human ocular biometry☆

    PubMed Central

    Augusteyn, Robert C.; Nankivil, Derek; Mohamed, Ashik; Maceo, Bianca; Pierre, Faradia; Parel, Jean-Marie

    2012-01-01

    The aim of this study was to examine growth of the human eye globe and cornea from early in gestation to late in adult life. Globe antero-posterior length, horizontal and vertical diameters, corneal horizontal and vertical (white to white) diameters and posterior pole to limbus distances were measured using digital calipers (±0.01 mm) in 541 postmortem eyes. Additional pre- and postnatal data for some of the dimensions were obtained from the literature. All dimensions examined increase rapidly during prenatal development but postnatal growth differs. Growth of globe antero-posterior length, vertical and horizontal diameters as well as corneal vertical and horizontal diameters stops within 1 year after birth. Logistic analysis is consistent with an asymptotic prenatal growth mode and no further growth after its completion around 1 year after birth. Horizontal and vertical globe diameters are the same at all ages but the corneal horizontal diameter is always larger than the vertical diameter. No differences could be detected between males and females in any of the ocular dimensions. Globe and corneal growth take place primarily during the prenatal growth mode and dimensions reach their maxima, shortly after birth. It is suggested that cessation of a growth stimulating signal at birth marks the end of the prenatal growth mode and that the small increases over the next year are due to cells already stimulated. Male and female eyes of the same age have the same globe and cornea dimensions. PMID:22819768

  7. Characterization of Ocular Surface Epithelial and Progenitor Cell Markers in Human Adipose Stromal Cells Derived from Lipoaspirates

    PubMed Central

    Martínez-Conesa, Eva M.; Espel, Enric; Reina, Manuel

    2012-01-01

    Purpose. The goal of this study was to characterize and compare mesenchymal stem cells from adult human adipose tissue (ADS cells) with progenitor cell lines from the human corneoscleral limbus and to analyze their potential for the expression of epithelial markers. Methods. Stem cell markers (CD34, CD90, p63, and ABCG2) and epithelial cell markers (CK3/76, CK12, CK76, CK19, and CK1/5/10/14) were analyzed by immunostaining, flow cytometry, Western blot analysis, and PCR methods. The authors assayed adhesion and proliferation on different extracellular matrix proteins. Results. ADS cells expressed a set of progenitor cell markers, including p63 and ABCG2. CK12 expression in ADS cell cultures increased spontaneously and progressively by differential adhesion, which demonstrates the cells' potential and capability to acquire epithelial-like cell characteristics. The authors observed an increase in the adhesion and proliferation of ADS cells seeded onto different basement membrane extracellular matrix proteins. Laminin substrates reduced the proliferative state of ADS cells. Conclusions. The expression of putative stem cell markers (CD90, ABCG2, and p63) and cytokeratins (CK12 and CK76) supports the hypothesis that ADS cells have self-renewal capacity and intrinsic plasticity that enables them to acquire some epithelial-like characteristics. Therefore, adult ADS cells could be a potential source for cell therapy in ocular surface regeneration. PMID:22199247

  8. Morphological changes and viability of primary cultured human ocular trabecular meshwork cells after exposure to air.

    PubMed

    Kopsachilis, Nikolaos; Tsaousis, Konstantinos T; Carifi, Gianluca; Welge-Luessen, Ulrich

    2014-06-01

    To investigate the possible toxic effect of air exposure for an in vitro model of primary human ocular trabecular meshwork cells (HTM). HTM were isolated from five donor eyes and cultivated at 37 °C. After reaching confluence the cells were seeded on two well chamber slides. The chamber slides were turned upside down in a Petri culture dish full of culture medium and filled with air using a 5 ml syringe, starting this way the exposure of the cells to the air. Subsequently they were placed in the incubation chamber at 37 °C. Six groups of HTM cultures were set up: group 1 consisted of samples in which HTM were exposed to air for 30 min, group 2 for 1 h, group 3 for 3 h, group 4 for 6 h, group 5 for 12 h and group 6 for 24 h. At 3 h after exposure, the morphology of the cells was still intact, at 6 h few cells appeared deformed and exhibited characteristics of more senescent cells. At 12 h after exposure to air the HTM cells started losing their typical morphology and appeared enlarged and compromised. Viability was superior to 94% in groups 1-3 while for groups 4, 5, 6 it was 82.7%, 39.5% and 12.7% respectively. The toxic effect of air exposure for the studied in vitro model of HTM is not significant for the time period of one to three hours. However it starts reducing viability and alternating morphology 6 h after exposure until the time period of 24 h, where the percentage of living cells is drastically decreased. Therefore, we suggest that the use of an air bubble especially in glaucomatous patients should be applied with caution. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. [Toxicity of topical ocular anti-allergic agents on human corneal epithelial cells in vitro].

    PubMed

    Li, Jun; Yan, Xiao-ming

    2010-01-01

    To investigate the cytotoxic effect of three kinds of topical ocular anti-allergic agent, including olopatadine 0.1% (A group), ketotifen fumarate 0.025% (B group) and pemirolast potassium 0.1% (C group), on cultured human corneal epithelial cells in vitro. Primary human corneal epithelial cells were cultured with keratinocyte serum-free medium. The cells were exposed to three kinds of topical ocular anti-allergic agent for a period of 10 min, 30 min, 2 h, 6 h, 12 h and 24 h. Toxicity was examined in three ways. MTT assay was used to quantify cytotoxicity. Cell membrane permeability and intracellular esterase activity were analyzed with live-dead viability staining of fluorescent calcein-AM/ethidium homodimer. The morphologic analysis was performed by light and scanning electron microscopy. Statistical methods adopted one-way ANOVA (analysis of variance) and Student-Newman-Keuls q test between each group. The P-value of 0.05 was considered statistically significant. (1) Morphologic changes: The Findings under the light microscopy were demonstrated that cells became round or edematic and detached from dishes after exposure to topical ocular anti-allergic agent. The cellular damage was more severe with longer exposure time and increasing concentration. Likewise, the electron microscopy examination showed reduced microvilli with longer exposure time and increasing concentration. The cellular changes of 20.0% olopatadine 0.1% were reduced when compared to the other agents. (2) Live/dead viability/cytotoxicity assay: Ethidium homodimeric permeates damaged cell membranes and results in red fluorescence. These results indicated that cell membrane damage caused by 20.0% olopatadine 0.1% at 6, 12, 24 h was less than those of ketotifen fumarate 0.025% and pemirolast potassium 0.1%. The data of A group were (29.7 +/- 2.6)%, (36.9 +/- 3.2)%, (51.2 +/- 4.3)%, B group were (36.5 +/- 3.1)%, (48.5 +/- 4.3)%, (75.5 +/- 3.8)% and C group were (37.1 +/- 2.2)%, (52.7 +/- 3.4)%, (71

  10. Ocular integration in the human visual cortex.

    PubMed

    Horton, Jonathan C

    2006-10-01

    Human striate cortex contains an orderly map of the contralateral visual field, which is distorted to make a disproportionate amount of tissue available for the representation of the macula. Engrafted on the retinotopic map is a system of alternating inputs known as ocular dominance columns. These columns consist of interleaved bands of geniculocortical afferents in layer 4C serving either the right eye or the left eye. They can be revealed in humans with a history of prior visual loss in one eye by processing striate cortex for cytochrome oxidase at autopsy. Because their geniculate input is segregated, cells within ocular dominance columns in layer 4C respond to stimulation of one eye only. These monocular cells converge onto binocular cells in other layers, integrating signals from the two eyes. The columns in humans appear similar to those found in many primate species, including the macaque. In the squirrel monkey, however, the occurrence of ocular dominance columns is highly variable. Some squirrel monkeys lack columns, yet they seem to have no impairment of visual function. In animals with weakly expressed columns, one can detect a cortical pattern of metabolic activity corresponding to retinal blood vessels. It appears because visual deprivation from shadows cast by blood vessels induces remodeling of geniculocortical afferents, in a manner akin to the shrinkage of ocular dominance columns from congenital cataract. Although the function of ocular dominance columns is unknown, their metabolism is altered in strabismus, suggesting a role in visual suppression.

  11. Comparative proteomics reveals human pluripotent stem cell-derived limbal epithelial stem cells are similar to native ocular surface epithelial cells

    PubMed Central

    Mikhailova, Alexandra; Jylhä, Antti; Rieck, Jochen; Nättinen, Janika; Ilmarinen, Tanja; Veréb, Zoltán; Aapola, Ulla; Beuerman, Roger; Petrovski, Goran; Uusitalo, Hannu; Skottman, Heli

    2015-01-01

    Limbal epithelial stem cells (LESCs) are tissue-specific stem cells responsible for renewing the corneal epithelium. Acute trauma or chronic disease affecting LESCs may disrupt corneal epithelial renewal, causing vision threatening and painful ocular surface disorders, collectively referred to as LESC deficiency (LESCD). These disorders cannot be treated with traditional corneal transplantation and therefore alternative cell sources for successful cell-based therapy are needed. LESCs derived from human pluripotent stem cells (hPSCs) are a prospective source for ocular surface reconstruction, yet critical evaluation of these cells is crucial before considering clinical applications. In order to quantitatively evaluate hPSC-derived LESCs, we compared protein expression in native human corneal cells to that in hPSC-derived LESCs using isobaric tag for relative and absolute quantitation (iTRAQ) technology. We identified 860 unique proteins present in all samples, including proteins involved in cell cycling, proliferation, differentiation and apoptosis, various LESC niche components, and limbal and corneal epithelial markers. Protein expression profiles were nearly identical in LESCs derived from two different hPSC lines, indicating that the differentiation protocol is reproducible, yielding homogeneous cell populations. Their protein expression profile suggests that hPSC-derived LESCs are similar to the human ocular surface epithelial cells, and possess LESC-like characteristics. PMID:26423138

  12. Intracellular trafficking of hyaluronic acid-chitosan oligomer-based nanoparticles in cultured human ocular surface cells

    PubMed Central

    Contreras-Ruiz, Laura; de la Fuente, María; Párraga, Jenny E.; López-García, Antonio; Fernández, Itziar; Seijo, Begoña; Sánchez, Alejandro; Calonge, Margarita

    2011-01-01

    Purpose Nanoparticles are a promising alternative for ocular drug delivery, and our group has proposed that they are especially suited for ocular mucosal disorders. The goal of the present study was to determine which internalization pathway is used by cornea-derived and conjunctiva-derived cell lines to take up hyaluronic acid (HA)-chitosan oligomer (CSO)-based nanoparticles (HA-CSO NPs). We also determined if plasmids loaded onto the NPs reached the cell nucleus. Methods HA-CSO NPs were made of fluoresceinamine labeled HA and CSO by ionotropic gelation and were conjugated with a model plasmid DNA for secreted alkaline phosphatase. Human epithelial cell lines derived from the conjunctiva and the cornea were exposed to HA-CSO NPs for 1 h and the uptake was investigated in living cells by fluorescence microscopy. The influence of temperature and metabolic inhibition, the effect of blocking hyaluronan receptors, and the inhibition of main endocytic pathways were studied by fluorometry. Additionally, the metabolic pathways implicated in the degradation of HA-CSO NPs were evaluated by lysosome identification. Results There was intracellular localization of plasmid-loaded HACSO NPs in both corneal and conjunctival cells. The intracellular presence of NPs diminished with time. HA-CSO NP uptake was significantly reduced by inhibition of active transport at 4 °C and by sodium azide. Uptake was also inhibited by blocking hyaluronan receptors with anti-CD44 Hermes-1 antibody, by excess HA, and by filipin, an inhibitor of caveolin-dependent endocytosis. HA-CSO NPs had no effect on cell viability. The transfection efficiency of the model plasmid was significantly higher in NP treated cells than in controls. Conclusions HA-CSO NPs were internalized by two different ocular surface cell lines by an active transport mechanism. The uptake was mediated by hyaluronan receptors through a caveolin-dependent endocytic pathway, yielding remarkable transfection efficiency. Most of HA

  13. HUMAN RETINAL ENDOTHELIAL CELLS AND ASTROCYTES CULTURED ON 3-D SCAFFOLDS FOR OCULAR DRUG DISCOVERY AND DEVELOPMENT.

    PubMed

    Beharry, Kay D; Cai, Charles L; Valencia, Gloria B; Lazzaro, Douglas; Valencia, Arwin M; Salomone, Fabrizio; Aranda, Jacob V

    2017-09-15

    Topical ocular ketorolac improves the outcomes of severe retinopathy of prematurity and when administered with systemic caffeine, decreases the severity of oxygen-induced retinopathy. We tested the hypothesis that co-cultures of human retinal endothelial cells (HRECs) and human retinal astrocytes (HRAs) on 3-dimensional (3-D) hydrogel scaffolds is a more representative biomimetic paradigm of the blood-retinal-barrier (BRB) than 2-D cultures, and should be utilized for preclinical drug discovery and development. Mono- and co-cultures of HRECs and HRAs were treated with standard doses of ketorolac, ibuprofen, and/or caffeine, and exposed to hyperoxia, intermittent hypoxia (IH), or normoxia on 2-D surfaces or 3-D biodegradable hydrogel scaffolds (AlgiMatrix or Geltrex). Media and cells were collected at 72hours post treatment for arachidonic acid metabolites. Cells cultured on 3-D scaffolds exhibited less oxidative stress and variability in drug responses. HRAs enhanced the responses of HRECs to drugs and changes in oxygen environment. PGE2 and PGI2 were the predominant prostanoids produced in response to IH, reflecting COX-2 immunoreactivity. We conclude that HRECs and HRAs co-cultured on 3-D scaffolds may recapitulate drug responses of the dynamic BRB and therefore should be implemented for preclinical ocular drug discovery and development. Published by Elsevier Inc.

  14. Histological observation of goblet cells following topical rebamipide treatment of the human ocular surface: A case report.

    PubMed

    Kase, Satoru; Shinohara, Toshiya; Kase, Manabu

    2015-02-01

    The topical administration of rebamipide (Mucosta®), an antiulcer agent, clinically increases the mucin level of tear film. The aim of this study was to report the histological changes of goblet cells following the topical administration of rebamipide to a patient with nevus of the lacrimal caruncle. A 62-year-old male exhibited a pigmented nodule located in the lacrimal caruncle in the left eye. An excisional biopsy and subsequent surgical resection were conducted at the caruncle, prior to and three months after topical rebamipide administration. Histologically, a biopsy specimen revealed a pigmented nevus beneath the caruncle epithelium containing a few goblet cells [4 cells/high power field (HPF)]. A few nevus cells were present at the surgical margin. By contrast, the secondary resected specimen obtained three months after the initiation of topical rebamipide treatment revealed the epithelium and nevus, where numerous goblet cells were present (28 cells/HPF), and mucin-like substances were markedly secreted from the goblet cells. Topical rebamipide markedly increased the number of goblet cells and stimulated the secretion of mucin-like substances in the caruncular tissue of a human patient. These results suggest that topical rebamipide is useful in patients following surgery and/or biopsy to support tissue repair of the ocular surface.

  15. Human Bone Marrow Stromal Cells Differentiate Into Corneal Tissue and Prevent Ocular Graft-Versus-Host Disease in Mice.

    PubMed

    Sánchez-Abarca, Luis Ignacio; Hernández-Galilea, Emiliano; Lorenzo, Rebeca; Herrero, Carmen; Velasco, Almudena; Carrancio, Soraya; Caballero-Velázquez, Teresa; Rodríguez-Barbosa, José Ignacio; Parrilla, Marta; Del Cañizo, Consuelo; San Miguel, Jesús; Aijón, José; Pérez-Simón, José Antonio

    2015-01-01

    Clinical trials have assessed the use of human bone marrow stromal cells (hBMSCs) for the treatment of immune-related disorders such as graft-versus-host disease (GVHD). In the current study, we show that GFP(+)-transduced hBMSCs generated from bone marrow migrate and differentiate into corneal tissue after subconjunctival injection in mice. Interestingly, these hBMSCs display morphological features of epithelial, stromal, and endothelial cells and appear at different layers and with different morphologies depending on their position within the epithelium. Furthermore, these cells display ultrastructural properties, such as bundles of intermediate filaments, interdigitations, and desmosomes with GFP(-) cells, which confirms their differentiation into corneal tissues. GFP(+)-transduced hBMSCs were injected at different time points into the right eye of lethally irradiated mice undergoing bone marrow transplantation, which developed ocular GVHD (oGVHD). Remarkably, hBMSCs massively migrate to corneal tissues after subconjunctival injection. Both macroscopic and histopathological examination showed minimal or no evidence of GVHD in the right eye, while the left eye, where no hBMSCs were injected, displayed features of GVHD. Thus, in the current study, we confirm that hBMSCs may induce their therapeutic effect at least in part by differentiation and regeneration of damaged tissues in the host. Our results provide experimental evidence that hBMSCs represent a potential cellular therapy to attenuate oGVHD.

  16. A Novel HLA (HLA-A*0201) Transgenic Rabbit Model for Preclinical Evaluation of Human CD8+ T Cell Epitope-Based Vaccines against Ocular Herpes

    PubMed Central

    Chentoufi, Aziz A.; Dasgupta, Gargi; Christensen, Neil D.; Hu, Jiafen; Choudhury, Zareen S.; Azeem, Arfan; Jester, James V.; Nesburn, Anthony B.; Wechsler, Steven L.; BenMohamed, Lbachir

    2013-01-01

    We introduced a novel humanized HLA-A*0201 transgenic (HLA Tg) rabbit model to assess the protective efficacy of a human CD8+ T cell epitope-based vaccine against primary ocular herpes infection and disease. Each of the three immunodominant human CD8+ T cell peptide epitopes from HSV-1 glycoprotein D (gD53–61, gD70–78, and gD278–286) were joined with a promiscuous human CD4+ T cell peptide epitope (gD49–82) to construct three separate pairs of CD4–CD8 peptides. Each CD4–CD8 peptide pair was then covalently linked to an Nε-palmitoyl–lysine residue via a functional base lysine amino group to construct CD4–CD8 lipopeptides. HLA Tg rabbits were immunized s.c. with a mixture of the three CD4–CD8 HSV-1 gD lipopeptides. The HSV-gD–specific T cell responses induced by the mixture of CD4–CD8 lipopeptide vaccine and the protective efficacy against acute virus replication and ocular disease were determined. Immunization induced HSV-gD49–82–specific CD4+ T cells in draining lymph node (DLN); induced HLA-restricted HSV-gD53–61, gD70–78, and gD278–286–specific CD8+ T cells in DLN, conjunctiva, and trigeminal ganglia and reduced HSV-1 replication in tears and corneal eye disease after ocular HSV-1 challenge. In addition, the HSV-1 epitope-specific CD8+ T cells induced in DLNs, conjunctiva, and the trigeminal ganglia were inversely proportional with corneal disease. The humanized HLA Tg rabbits appeared to be a useful preclinical animal model for investigating the immunogenicity and protective efficacy of human CD8+ T cell epitope-based prophylactic vaccines against ocular herpes. The relevance of HLA Tg rabbits for future investigation of human CD4–CD8 epitope-based therapeutic vaccines against recurrent HSV-1 is discussed. PMID:20124097

  17. A novel HLA (HLA-A*0201) transgenic rabbit model for preclinical evaluation of human CD8+ T cell epitope-based vaccines against ocular herpes.

    PubMed

    Chentoufi, Aziz A; Dasgupta, Gargi; Christensen, Neil D; Hu, Jiafen; Choudhury, Zareen S; Azeem, Arfan; Jester, James V; Nesburn, Anthony B; Wechsler, Steven L; BenMohamed, Lbachir

    2010-03-01

    We introduced a novel humanized HLA-A*0201 transgenic (HLA Tg) rabbit model to assess the protective efficacy of a human CD8(+) T cell epitope-based vaccine against primary ocular herpes infection and disease. Each of the three immunodominant human CD8(+) T cell peptide epitopes from HSV-1 glycoprotein D (gD(53-61), gD(70-78), and gD(278-286)) were joined with a promiscuous human CD4(+) T cell peptide epitope (gD(49-82)) to construct three separate pairs of CD4-CD8 peptides. Each CD4-CD8 peptide pair was then covalently linked to an N(epsilon)-palmitoyl-lysine residue via a functional base lysine amino group to construct CD4-CD8 lipopeptides. HLA Tg rabbits were immunized s.c. with a mixture of the three CD4-CD8 HSV-1 gD lipopeptides. The HSV-gD-specific T cell responses induced by the mixture of CD4-CD8 lipopeptide vaccine and the protective efficacy against acute virus replication and ocular disease were determined. Immunization induced HSV-gD(49-82)-specific CD4(+) T cells in draining lymph node (DLN); induced HLA-restricted HSV-gD(53-61), gD(70-78), and gD(278-286)-specific CD8(+) T cells in DLN, conjunctiva, and trigeminal ganglia and reduced HSV-1 replication in tears and corneal eye disease after ocular HSV-1 challenge. In addition, the HSV-1 epitope-specific CD8(+) T cells induced in DLNs, conjunctiva, and the trigeminal ganglia were inversely proportional with corneal disease. The humanized HLA Tg rabbits appeared to be a useful preclinical animal model for investigating the immunogenicity and protective efficacy of human CD8(+) T cell epitope-based prophylactic vaccines against ocular herpes. The relevance of HLA Tg rabbits for future investigation of human CD4-CD8 epitope-based therapeutic vaccines against recurrent HSV-1 is discussed.

  18. Science and Art of Cell-Based Ocular Surface Regeneration.

    PubMed

    Singh, Vivek; Shukla, Sachin; Ramachandran, Charanya; Mishra, Dilip Kumar; Katikireddy, Kishore R; Lal, Ikeda; Chauhan, Sunil K; Sangwan, Virender S

    2015-01-01

    The potential cause of blindness worldwide includes diseases of the cornea, ocular surface (limbal stem cell deficiency, allergic conjunctivitis, dry eye diseases), and retinal diseases. The presence of stem cells (limbal stem cells) in the basal region of the limbus makes it an important tool for the ocular regeneration and also in maintaining the transparency of eye by replacing the corneal epithelium continuously. Various surgical modalities have been developed like cultured limbal epithelial transplantation, cultured oral mucosal epithelial transplantation, simple limbal epithelial transplantation, etc., utilizing the cell-based regenerative properties to treat limbal disorder. Cell-based therapies for ocular repair and regeneration comprise a major hope by therapies involving the mesenchymal stem cells, embryonic stem cells, and limbal stem cells for the restoration of vision in individuals whose ocular tissue has been irreversibly damaged by disease or trauma. This review explores critical needs in human disease mainly the ocular problem where cell-based therapeutics is exceptionally well suited and also the use of animal models, various artificial scaffolds, as well as advancement in clinical technique to challenge the current demand to overcome corneal blindness. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Effects of benzalkonium chloride-preserved, polyquad-preserved, and sofZia-preserved topical glaucoma medications on human ocular epithelial cells.

    PubMed

    Ammar, David A; Noecker, Robert J; Kahook, Malik Y

    2010-11-01

    INTRODUCTION|: To investigate potentially adverse effects of different topical glaucoma medications and preservatives on cultured ocular epithelial cells. METHODS|: Confluent cultures of human corneal (10.014 pRSV-T) and conjunctival cells (1-5c-4) were assayed with 100 μL of different glaucoma medications for 25 minutes at 37°C and 5% CO₂. We also tested the preservative sofZia® (Alcon Laboratories, Fort Worth, TX, USA), as well as a range of concentrations of the preservative benzalkonium chloride (BAK; 0.001% to 0.050%). Balanced salt solution was used as the "live" control and a solution containing 70% methanol and 0.2% saponin was used as a "dead" control. The LIVE/DEAD viability/cytotoxicity kit (Invitrogen, Carlsbad, CA, USA) was used to determine the percentage of dead and live cells via ethidium homodimer and calcein fluorescence, respectively. RESULTS|: The toxicity of the prostaglandin analogs latanoprost, tafluprost and travoprost preserved with BAK was similar to the toxicity observed in their respective BAK concentrations. The prostaglandin analog travoprost (0.004%) preserved with the oxidizing preservative sofZia had much greater corneal and conjunctival cell survival than travoprost preserved with BAK. Travoprost (0.004%) containing polyquad also performed statistically better than its BAK-preserved formulation. CONCLUSION|: Ocular surface side effects have previously been demonstrated with chronic, long-term exposure to intraocular pressure-lowering medications containing the common preservative BAK. BAK alone has significant in-vitro cytotoxicity to cultured ocular epithelial cells. Substitution of BAK with polyquad or sofZia resulted in significantly higher percentages of live conjunctival and corneal cells. Further studies are needed to understand the- clinical implications of these findings.

  20. The role of nitric oxide in ocular surface cells.

    PubMed Central

    Kim, Jae Chan; Park, Gun Sic; Kim, Jin Kook; Kim, Young Myeong

    2002-01-01

    The role of nitric oxide (NO) in the ocular surface remains unknown. We investigated the conditions leading to an increase of NO generation in tear and the main sources of NO in ocular surface tissue. We evaluated the dual action (cell survival or cell death) of NO depending on its amount. We measured the concentration of nitrite plus nitrate in the tears of ocular surface diseases and examined the main source of nitric oxide synthase (NOS). When cultured human corneal fibroblast were treated with NO producing donor with or without serum, the viabilities of cells was studied. We found that the main sources of NO in ocular surface tissue were corneal epithelium, fibroblast, endothelium, and inflammatory cells. Three forms of NOS (eNOS, bNOS, and iNOS) were expressed in experimentally induced inflammation. In the fibroblast culture system, the NO donor (SNAP, S-nitroso-N-acetyl-D, L-penicillamine) prevented the death of corneal fibroblast cells caused by serum deprivation in a dose dependent manner up to 500 micrometer SNAP, but a higher dose decreased cell viability. This study suggested that NO might act as a double-edged sword in ocular surface diseases depending on the degree of inflammation related with NO concentration. PMID:12068145

  1. Ocular inflammation and endoplasmic reticulum stress are attenuated by supplementation with grape polyphenols in human retinal pigmented epithelium cells and in C57BL/6 mice.

    PubMed

    Ha, Jung-Heun; Shil, Pollob Kumar; Zhu, Ping; Gu, Liwei; Li, Qiuhong; Chung, Soonkyu

    2014-06-01

    Inflammation and endoplasmic reticulum (ER) stress are common denominators for vision-threatening diseases such as diabetic retinopathy and age-related macular degeneration. Based on our previous study, supplementation with muscadine grape polyphenols (MGPs) alleviated systemic insulin resistance and proinflammatory responses. In this study, we hypothesized that MGPs would also be effective in attenuating ocular inflammation and ER stress. We tested this hypothesis using the human retinal pigmented epithelium (ARPE-19) cells and C57BL/6 mice. In ARPE-19 cells, tumor necrosis factor-α-induced proinflammatory gene expression of interleukin (IL)-1β, IL-6, and monocyte chemotactic protein-1 was decreased by 35.0%, 68.8%, and 62.5%, respectively, with MGP pretreatment, which was primarily due to the diminished mitogen-activated protein kinase activation and subsequent reduction of nuclear factor κ-B activation. Consistently, acute ocular inflammation and leukocyte infiltration were almost completely dampened (>95%) by MGP supplementation (100-200 mg/kg body weight) in C57BL/6 mice. Moreover, MGPs reduced inflammation-mediated loss of tight junctions and retinal permeability. To further investigate the protective roles of MGPs against ER stress, ARPE-19 cells were stimulated with thapsigargin. Pretreatment with MGPs significantly decreased the following: 1) ER stress-mediated vascular endothelial growth factor secretion (3.47 ± 0.06 vs. 1.58 ± 0.02 μg/L, P < 0.0001), 2) unfolded protein response, and 3) early apoptotic cell death (64.4 ± 6.85 vs. 33.7 ± 4.32%, P = 0.0003). Collectively, we have demonstrated that MGP is effective in attenuating ocular inflammation and ER stress. Our work also suggests that MGP may provide a novel dietary strategy to prevent vision-threatening retinal diseases. © 2014 American Society for Nutrition.

  2. Antimicrobial role of human meibomian lipids at the ocular surface.

    PubMed

    Mudgil, Poonam

    2014-10-14

    Human meibomian lipids form the outermost lipid layer of the tear film and serve many important functions to maintain its integrity. Although not investigated earlier, these lipids may have antimicrobial properties that help in strengthening the innate host defense of tears at the ocular surface. The aim of this study was to investigate the antimicrobial role of human meibomian lipids. Ocular pathogenic bacteria, Staphylococcus aureus 31, Pseudomonas aeruginosa 19, Pseudomonas aeruginosa 20, and Serratia marcescens 35, were grown in the presence and absence of human meibomian lipids in an artificial tear solution at the physiological temperature. Viable counts were obtained to note the number of bacteria surviving the treatment with meibomian lipids. Bacterial cells were imaged using scanning electron microscopy to observe the damages caused by meibomian lipids. Viable count results showed that in the presence of meibomian lipids, growth of all bacteria was considerably lower. Scanning electron microscopy showed that meibomian lipids caused extensive cellular damage to bacteria as manifested in smaller size, loss of aggregation, abnormal phenotype, cellular distortion, damaged cell wall, and cell lysis. This is the first-ever report of the antimicrobial role of human meibomian lipids. These lipids possess antimicrobial properties against both Gram-positive and Gram-negative bacteria and are involved in the innate host defense of tears in protecting the ocular surface against microbial pathogens. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

  3. Ocular surface reconstruction using stem cell and tissue engineering.

    PubMed

    Nakamura, Takahiro; Inatomi, Tsutomu; Sotozono, Chie; Koizumi, Noriko; Kinoshita, Shigeru

    2016-03-01

    Most human sensory information is gained through eyesight, and integrity of the ocular surface, including cornea and conjunctiva, is known to be indispensable for good vision. It is believed that severe damage to corneal epithelial stem cells results in devastating ocular surface disease, and many researchers and scientists have tried to reconstruct the ocular surface using medical and surgical approaches. Ocular surface reconstruction via regenerative therapy is a newly developed medical field that promises to be the next generation of therapeutic modalities, based on the use of tissue-specific stem cells to generate biological substitutes and improve tissue functions. The accomplishment of these objectives depends on three key factors: stem cells, which have highly proliferative capacities and longevities; the substrates determining the environmental niche; and growth factors that support them appropriately. This manuscript describes the diligent development of ocular surface reconstruction using tissue engineering techniques, both past and present, and discusses and validates their future use for regenerative therapy in this field. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Spectral imaging of the human ocular fundus

    NASA Astrophysics Data System (ADS)

    Truitt, Paul Wiley

    Introduction. The objective of this work was to demonstrate a high spectral and spatial resolution fundus imager and to assess its utility in visualizing and characterizing normal anatomical and pathological tissue classes in the human ocular fundus. The ocular fundus (posterior portion of the eye) affords a unique opportunity to directly observe neural and vascular tissue in vivo. Many ocular and systemic diseases manifest changes in the normal fundus anatomy. Current examination techniques are not optimized to detect changes prior to the formation of damaging lesions. Spectral imaging may allow visualization of disease states before the onset of traditional clinical signs. Normal tissue in the eye has distinct spectral characteristics determined by specific structural organization and the presence of specific chemical substances and ocular pigments. Pathological states result in physical and chemical changes to the tissue. Spectral imaging exploits the differences in the spectral characteristics to separate different classes of material. When these spectral properties are combined with the spatial context of the image, improved visualization and detection is possible. Methods. Two independent spectral imaging devices were developed and integrated to a commercially available Zeiss fundus camera. Spectral data were collected in order to characterize the normal anatomical tissue classes and to assess the usefulness of spectral features for improved class discernment. Spectral images were collected for 14 subjects Diabetic Retinopathy were imaged. Mean spectral curves were produced for each class and for each subject. These spectral curves were normalized to remove the contribution from the pigment melanin (the major pigment associated with variation in fundus pigmentation) and modeled with a piece-wise linear function consisting of a DC offset and four slopes. Results. Differences in the shape of the spectral curve exist between macular edema and normal macular and

  5. Categorical evaluation of the ocular irritancy of cosmetic and consumer products by human ocular instillation procedures.

    PubMed

    Gao, Yang; Kanengiser, Bruce E

    2004-01-01

    The assessment of ocular irritation potential is an important part of safety testing for cosmetic and consumer products. The purpose of this investigation was to examine ocular irritancy levels elicited in humans by various categories of a specific class of cosmetic and consumer products that have a potential to enter the eye inadvertently during use. Test materials assessed belonged to one of seven categories, which included liquid makeup, shampoo, baby wash, mascara, eye makeup remover, powder eye shadow, and facial cleanser. These test materials were evaluated by human ocular instillation, followed by examinations, for which subjective perceptions of irritation were recorded, and component areas of ocular tissues were individually examined for inflammation and for the area and density of fluorescein staining patterns at 30 seconds and at 5, 15, 60, and 120 minutes post-instillation. Subjective and objective ocular irritation scores of 410 eyes were analyzed by product classification. Average score levels were determined for subjective responses, inflammation, and fluorescein staining patterns. This investigation determined that irritation levels of the evaluated test materials varied markedly with respect to product category, type of ocular irritation, and ocular tissue, demonstrating that these factors are important considerations for the prediction of the ocular irritancy of a test material.

  6. A Herpes Simplex Virus Type 1 Human Asymptomatic CD8+ T-Cell Epitopes-Based Vaccine Protects Against Ocular Herpes in a “Humanized” HLA Transgenic Rabbit Model

    PubMed Central

    Srivastava, Ruchi; Khan, Arif A.; Huang, Jiawei; Nesburn, Anthony B.; Wechsler, Steven L.; BenMohamed, Lbachir

    2015-01-01

    Purpose. A clinical vaccine that protects from ocular herpes simplex virus type 1 (HSV-1) infection and disease still is lacking. In the present study, preclinical vaccine trials of nine asymptomatic (ASYMP) peptides, selected from HSV-1 glycoproteins B (gB), and tegument proteins VP11/12 and VP13/14, were performed in the “humanized” HLA–transgenic rabbit (HLA-Tg rabbit) model of ocular herpes. We recently reported that these peptides are highly recognized by CD8+ T cells from “naturally” protected HSV-1–seropositive healthy ASYMP individuals (who have never had clinical herpes disease). Methods. Mixtures of three ASYMP CD8+ T-cell peptides derived from either HSV-1 gB, VP11/12, or VP13/14 were delivered subcutaneously to different groups of HLA-Tg rabbits (n = 10) in incomplete Freund's adjuvant, twice at 15-day intervals. The frequency and function of HSV-1 epitope-specific CD8+ T cells induced by these peptides and their protective efficacy, in terms of survival, virus replication in the eye, and ocular herpetic disease were assessed after an ocular challenge with HSV-1 (strain McKrae). Results. All mixtures elicited strong and polyfunctional IFN-γ– and TNF-α–producing CD107+CD8+ cytotoxic T cells, associated with a significant reduction in death, ocular herpes infection, and disease (P < 0.015). Conclusions. The results of this preclinical trial support the screening strategy used to select the HSV-1 ASYMP CD8+ T-cell epitopes, emphasize their valuable immunogenic and protective efficacy against ocular herpes, and provide a prototype vaccine formulation that may be highly efficacious for preventing ocular herpes in humans. PMID:26098469

  7. Ocular Stem Cell Research from Basic Science to Clinical Application: A Report from Zhongshan Ophthalmic Center Ocular Stem Cell Symposium.

    PubMed

    Ouyang, Hong; Goldberg, Jeffrey L; Chen, Shuyi; Li, Wei; Xu, Guo-Tong; Li, Wei; Zhang, Kang; Nussenblatt, Robert B; Liu, Yizhi; Xie, Ting; Chan, Chi-Chao; Zack, Donald J

    2016-03-22

    Stem cells hold promise for treating a wide variety of diseases, including degenerative disorders of the eye. The eye is an ideal organ for stem cell therapy because of its relative immunological privilege, surgical accessibility, and its being a self-contained system. The eye also has many potential target diseases amenable to stem cell-based treatment, such as corneal limbal stem cell deficiency, glaucoma, age-related macular degeneration (AMD), and retinitis pigmentosa (RP). Among them, AMD and glaucoma are the two most common diseases, affecting over 200 million people worldwide. Recent results on the clinical trial of retinal pigment epithelial (RPE) cells from human embryonic stem cells (hESCs) and induced pluripotent stem cells (iPSCs) in treating dry AMD and Stargardt's disease in the US, Japan, England, and China have generated great excitement and hope. This marks the beginning of the ocular stem cell therapy era. The recent Zhongshan Ophthalmic Center Ocular Stem Cell Symposium discussed the potential applications of various stem cell types in stem cell-based therapies, drug discoveries and tissue engineering for treating ocular diseases.

  8. Ocular Stem Cell Research from Basic Science to Clinical Application: A Report from Zhongshan Ophthalmic Center Ocular Stem Cell Symposium

    PubMed Central

    Ouyang, Hong; Goldberg, Jeffrey L.; Chen, Shuyi; Li, Wei; Xu, Guo-Tong; Li, Wei; Zhang, Kang; Nussenblatt, Robert B.; Liu, Yizhi; Xie, Ting; Chan, Chi-Chao; Zack, Donald J.

    2016-01-01

    Stem cells hold promise for treating a wide variety of diseases, including degenerative disorders of the eye. The eye is an ideal organ for stem cell therapy because of its relative immunological privilege, surgical accessibility, and its being a self-contained system. The eye also has many potential target diseases amenable to stem cell-based treatment, such as corneal limbal stem cell deficiency, glaucoma, age-related macular degeneration (AMD), and retinitis pigmentosa (RP). Among them, AMD and glaucoma are the two most common diseases, affecting over 200 million people worldwide. Recent results on the clinical trial of retinal pigment epithelial (RPE) cells from human embryonic stem cells (hESCs) and induced pluripotent stem cells (iPSCs) in treating dry AMD and Stargardt’s disease in the US, Japan, England, and China have generated great excitement and hope. This marks the beginning of the ocular stem cell therapy era. The recent Zhongshan Ophthalmic Center Ocular Stem Cell Symposium discussed the potential applications of various stem cell types in stem cell-based therapies, drug discoveries and tissue engineering for treating ocular diseases. PMID:27102165

  9. IGF-1 Signaling Plays an Important Role in the Formation of Three-Dimensional Laminated Neural Retina and Other Ocular Structures From Human Embryonic Stem Cells.

    PubMed

    Mellough, Carla B; Collin, Joseph; Khazim, Mahmoud; White, Kathryn; Sernagor, Evelyne; Steel, David H W; Lako, Majlinda

    2015-08-01

    We and others have previously demonstrated that retinal cells can be derived from human embryonic stem cells (hESCs) and induced pluripotent stem cells under defined culture conditions. While both cell types can give rise to retinal derivatives in the absence of inductive cues, this requires extended culture periods and gives lower overall yield. Further understanding of this innate differentiation ability, the identification of key factors that drive the differentiation process, and the development of clinically compatible culture conditions to reproducibly generate functional neural retina is an important goal for clinical cell based therapies. We now report that insulin-like growth factor 1 (IGF-1) can orchestrate the formation of three-dimensional ocular-like structures from hESCs which, in addition to retinal pigmented epithelium and neural retina, also contain primitive lens and corneal-like structures. Inhibition of IGF-1 receptor signaling significantly reduces the formation of optic vesicle and optic cups, while exogenous IGF-1 treatment enhances the formation of correctly laminated retinal tissue composed of multiple retinal phenotypes that is reminiscent of the developing vertebrate retina. Most importantly, hESC-derived photoreceptors exhibit advanced maturation features such as the presence of primitive rod- and cone-like photoreceptor inner and outer segments and phototransduction-related functional responses as early as 6.5 weeks of differentiation, making these derivatives promising candidates for cell replacement studies and in vitro disease modeling.

  10. Ocular Drug Delivery; Impact of in vitro Cell Culture Models

    PubMed Central

    Barar, Jaleh; Asadi, Masoud; Mortazavi-Tabatabaei, Seyed Abdolreza; Omidi, Yadollah

    2009-01-01

    Normal vision depends on the optimal function of ocular barriers and intact membranes that selectively regulate the environment of ocular tissues. Novel pharmacotherapeutic modalities have aimed to overcome such biological barriers which impede efficient ocular drug delivery. To determine the impact of ocular barriers on research related to ophthalmic drug delivery and targeting, herein we provide a review of the literature on isolated primary or immortalized cell culture models which can be used for evaluation of ocular barriers. In vitro cell cultures are valuable tools which serve investigations on ocular barriers such as corneal and conjunctival epithelium, retinal pigment epithelium and retinal capillary endothelium, and can provide platforms for further investigations. Ocular barrier-based cell culture systems can be simply set up and used for drug delivery and targeting purposes as well as for pathological and toxicological research. PMID:23198080

  11. Human ocular carotenoid-binding proteins†

    PubMed Central

    Li, Binxing; Vachali, Preejith

    2014-01-01

    Two dietary carotenoids, lutein and zeaxanthin, are specifically delivered to the human macula at the highest concentration anywhere in the body. Whenever a tissue exhibits highly selective uptake of a compound, it is likely that one or more specific binding proteins are involved in the process. Over the past decade, our laboratory has identified and characterized several carotenoid-binding proteins from human retina including a pi isoform of glutathione S-transferase (GSTP1) as a zeaxanthin-binding protein, a member of the steroidogenic acute regulatory domain (StARD) family as a lutein-binding protein, and tubulin as a less specific, but higher capacity site for carotenoid deposition. In this article, we review the purification and characterization of these carotenoid-binding proteins, and we relate these ocular carotenoid-binding proteins to the transport and uptake role of serum lipoproteins and scavenger receptor proteins in a proposed pathway for macular pigment carotenoid delivery to the human retina. PMID:20820671

  12. Plasticity of the human otolith-ocular reflex

    NASA Technical Reports Server (NTRS)

    Wall, C. 3rd; Smith, T. R.; Furman, J. M.

    1992-01-01

    The eye movement response to earth vertical axis rotation in the dark, a semicircular canal stimulus, can be altered by prior exposure to combined visual-vestibular stimuli. Such plasticity of the vestibulo-ocular reflex has not been described for earth horizontal axis rotation, a dynamic otolith stimulus. Twenty normal human subjects underwent one of two types of adaptation paradigms designed either to attenuate or enhance the gain of the semicircular canal-ocular reflex prior to undergoing otolith-ocular reflex testing with horizontal axis rotation. The adaptation paradigm paired a 0.2 Hz sinusoidal rotation about a vertical axis with a 0.2 Hz optokinetic stripe pattern that was deliberately mismatched in peak velocity. Pre- and post-adaptation horizontal axis rotations were at 60 degrees/s in the dark and produced a modulation in the slow component velocity of nystagmus having a frequency of 0.17 Hz due to putative stimulation of the otolith organs. Results showed that the magnitude of this modulation component response was altered in a manner similar to the alteration in semicircular canal-ocular responses. These results suggest that physiologic alteration of the vestibulo-ocular reflex using deliberately mismatched visual and semicircular canal stimuli induces changes in both canal-ocular and otolith-ocular responses. We postulate, therefore, that central nervous system pathways responsible for controlling the gains of canal-ocular and otolith-ocular reflexes are shared.

  13. Plasticity of the human otolith-ocular reflex

    NASA Technical Reports Server (NTRS)

    Wall, C. 3rd; Smith, T. R.; Furman, J. M.

    1992-01-01

    The eye movement response to earth vertical axis rotation in the dark, a semicircular canal stimulus, can be altered by prior exposure to combined visual-vestibular stimuli. Such plasticity of the vestibulo-ocular reflex has not been described for earth horizontal axis rotation, a dynamic otolith stimulus. Twenty normal human subjects underwent one of two types of adaptation paradigms designed either to attenuate or enhance the gain of the semicircular canal-ocular reflex prior to undergoing otolith-ocular reflex testing with horizontal axis rotation. The adaptation paradigm paired a 0.2 Hz sinusoidal rotation about a vertical axis with a 0.2 Hz optokinetic stripe pattern that was deliberately mismatched in peak velocity. Pre- and post-adaptation horizontal axis rotations were at 60 degrees/s in the dark and produced a modulation in the slow component velocity of nystagmus having a frequency of 0.17 Hz due to putative stimulation of the otolith organs. Results showed that the magnitude of this modulation component response was altered in a manner similar to the alteration in semicircular canal-ocular responses. These results suggest that physiologic alteration of the vestibulo-ocular reflex using deliberately mismatched visual and semicircular canal stimuli induces changes in both canal-ocular and otolith-ocular responses. We postulate, therefore, that central nervous system pathways responsible for controlling the gains of canal-ocular and otolith-ocular reflexes are shared.

  14. T cell immunoregulation in active ocular toxoplasmosis.

    PubMed

    Cordeiro, Cynthia A; Vieira, Erica L M; Castro, Vinicius M; Dutra, Walderez O; Costa, Rogerio A; Orefice, Juliana L; Campos, Wesley R; Orefice, Fernando; Young, Lucy H; Teixeira, Antonio Lucio

    2017-04-01

    Toxoplasma gondii infection is an important cause of infectious ocular disease. The physiopathology of retinochoroidal lesions associated with this infection is not completely understood. The present study was undertaken to investigate cytokine production by T cells from individuals with active toxoplasmic retinochoroiditis (TR) comparing with controls. Eighteen patients with active TR and 15 healthy controls (6 controls IgG(+) to Toxoplasma and 9 negative controls) were included in the study. Peripheral blood mononuclear cells were incubated in the presence or absence of T. gondii antigen (STAg), and stained against CD4, CD8, TNF, IL-10 and IFN-γ. Baseline expression of cytokines was higher in TR/IgG(+) patients in comparison with controls. Cytokine expression was not increased by STAg in vitro stimulation in controls. After stimulation, TR/IgG(+) patients' lymphocytes increased cytokine as compared to cultures from both controls. While T cells were the main source of IL-10, but also IFN-γ and TNF, other lymphocyte populations were relevant source of inflammatory cytokines. Interestingly, it was observed a negative correlation between ocular lesion size and IL-10 expression by CD4(+) lymphocytes. This study showed that T cells are the main lymphocyte populations expressing IL-10 in patients with TR. Moreover, expression of IL-10 plays a protective role in active TR.

  15. Ocular cells and light: harmony or conflict?

    PubMed

    Jurja, Sanda; Hîncu, Mihaela; Dobrescu, Mihaela Amelia; Golu, Andreea Elena; Bălăşoiu, Andrei Theodor; Coman, Mălina

    2014-01-01

    Vision is based on the sensitivity of the eye to visible rays of the solar spectrum, which allows the recording and transfer of visual information by photoelectric reaction. Any electromagnetic radiation, if sufficiently intense, may cause damages in living tissues. In a changing environment, the aim of this paper is to point out the impact of light radiation on ocular cells, with its phototoxicity potential on eye tissues. In fact, faced with light and oxygen, the eye behaves like an ephemeral aggregate of unstable molecules, like a temporary crystallization threatened with entropia.

  16. Proteomics Analysis of Molecular Risk Factors in the Ocular Hypertensive Human Retina

    PubMed Central

    Yang, Xiangjun; Hondur, Gözde; Li, Ming; Cai, Jian; Klein, Jon B.; Kuehn, Markus H.; Tezel, Gülgün

    2015-01-01

    Purpose To better understand ocular hypertension–induced early molecular alterations that may determine the initiation of neurodegeneration in human glaucoma, this study analyzed retinal proteomic alterations in the ocular hypertensive human retina. Methods Retina samples were obtained from six human donors with ocular hypertension (without glaucomatous injury) and six age- and sex-matched normotensive controls. Retinal proteins were analyzed by two-dimensional LC-MS/MS (liquid chromatography and linear ion trap mass spectrometry) using oxygen isotope labeling for relative quantification of protein expression. Proteomics data were validated by Western blot and immunohistochemical analyses of selected proteins. Results Out of over 2000 retinal proteins quantified, hundreds exhibited over 2-fold increased or decreased expression in ocular hypertensive samples relative to normotensive controls. Bioinformatics linked the proteomics datasets to various pathways important for maintenance of cellular homeostasis in the ocular hypertensive retina. Upregulated proteins included various heat shock proteins, ubiquitin proteasome pathway components, antioxidants, and DNA repair enzymes, while many proteins involved in mitochondrial oxidative phosphorylation exhibited downregulation in the ocular hypertensive retina. Despite the altered protein expression reflecting intrinsic adaptive/protective responses against mitochondrial energy failure, oxidative stress, and unfolded proteins, no alterations suggestive of an ongoing cell death process or neuroinflammation were detectable. Conclusions This study provides information about ocular hypertension–related molecular risk factors for glaucoma development. Molecular alterations detected in the ocular hypertensive human retina as opposed to previously detected alterations in human donor retinas with clinically manifest glaucoma suggest that proteome alterations determine the individual threshold to tolerate the ocular

  17. Cultured human ocular surface epithelium on therapeutic contact lenses

    PubMed Central

    Girolamo, Nick Di; Chui, Jeanie; Wakefield, Denis; Coroneo, Minas T

    2007-01-01

    Background This study was initiated after observation of some intriguing epithelial growth properties of contact lenses used as a bandage for patients after pterygium surgery. Aim To determine the efficacy of culturing human ocular surface epithelial cells on therapeutic contact lenses in autologous serum with a view of using this system to transfer epithelial cells to patients with persistent corneal or limbal defects. Methods Excess graft tissue resected from patients undergoing pterygium surgery (n = 3) consisting of limbal epithelium was placed on siloxane–hydrogel contact lenses (lotrafilcon A and balafilcon A). Limbal explants were cultured in media with 10% autologous serum. Morphology, proliferative capacity and cytokeratin profile were determined by phase contrast, light and electron microscopy, and immunohistochemical analysis. Results Lotrafilcon A contact lenses sustained proliferation and migration from limbal tissue. Cells became confluent after 10–14 days and consisted of 2–3 layers with a corneal phenotype (CK3+/CK12+/CK19−) and a propensity to proliferate (p63+). Electron microscopy showed microvilli on the apical surface with adhesive projections, indicating that these cells were stable and likely to survive for a long term. Growth was not observed from limbal explants cultured on balafilcon A contact lenses. Conclusion A method for culturing human ocular surface epithelium on contact lenses that may facilitate expansion and transfer of autologous limbal epithelial cells while avoiding the risks associated with transplanting allogeneic tissue has been developed. This technique may be potentially useful for the treatment of patients with limbal stem cell deficiency. PMID:16987897

  18. Cortisol Biosynthesis in the Human Ocular Surface Innate Immune Response

    PubMed Central

    Walker, Elizabeth A.; Bujalska, Iwona J.; Alsalem, Jawaher; Williams, Geraint P.; Sreekantam, Sreekanth; Taylor, Angela E.; Tallouzi, Mohammad; Southworth, H. Susan; Murray, Philip I.; Wallace, Graham R.; Rauz, Saaeha

    2014-01-01

    Innate immune responses have a critical role in regulating sight-threatening ocular surface (OcS) inflammation. While glucocorticoids (GCs) are frequently used to limit tissue damage, the role of intracrine GC (cortisol) bioavailability via 11-beta-hydroxysteroid dehydrogenase type 1 (11β-HSD1) in OcS defense, remains unresolved. We found that primary human corneal epithelial cells (PHCEC), fibroblasts (PHKF) and allogeneic macrophages (M1, GM-CSF; M2, M-CSF) were capable of generating cortisol (M1>PHKF>M2>PHCEC) but in corneal cells, this was independent of Toll-like receptor (TLR) activation. While PolyI∶C induced maximal cytokine and chemokine production from both PHCEC (IFNγ, CCL2, CCL3, and (CCL4), IL6, CXCL10, CCL5, TNFα) and PHKF (CCL2, IL-6, CXCL10, CCL5), only PHKF cytokines were inhibited by GCs. Both Poly I∶C and LPS challenged-corneal cells induced M1 chemotaxis (greatest LPS-PHKF (250%), but down-regulated M1 11β-HSD1 activity (30 and 40% respectively). These data were supported by clinical studies demonstrating reduced human tear film cortisol∶cortisone ratios (a biomarker of local 11β-HSD1 activity) in pseudomonas keratitis (1∶2.9) versus healthy controls (1∶1.3; p<0.05). This contrasted with putative TLR3-mediated OcS disease (Stevens-Johnson Syndrome, Mucous membrane pemphigoid) where an increase in cortisol∶cortisone ratio was observed (113.8∶1; p<0.05). In summary, cortisol biosynthesis in human corneal cells is independent of TLR activation and is likely to afford immunoprotection under physiological conditions. Contribution to ocular mucosal innate responses is dependent on the aetiology of immunological challenge. PMID:24736562

  19. Modulation of Ocular Inflammation by Mesenchymal Stem Cells

    DTIC Science & Technology

    2017-03-01

    1 AWARD NUMBER: W81XWH-15-1-0024 TITLE: Modulation of Ocular Inflammation by Mesenchymal Stem Cells PRINCIPAL INVESTIGATOR: Sunil Chauhan...2016 4. TITLE AND SUBTITLE Modulation of Ocular Inflammation by Mesenchymal Stem Cells 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-15-1-0024 5c...as corticosteroids. These non-specific treatments typically target both pathogenic and regulatory cells of the immune system, and are associated with

  20. ELECTRICAL SIGNALING IN CONTROL OF OCULAR CELL BEHAVIORS

    PubMed Central

    Zhao, Min; Chalmers, Laura; Cao, Lin; Viera, Ana C.; Mannis, Mark; Reid, Brian

    2011-01-01

    Epithelia of the cornea, lens and retina contain a vast array of ion channels and pumps. Together they produce a polarized flow of ions in and out of cells, as well as across the epithelia. These naturally occurring ion fluxes are essential to the hydration and metabolism of the ocular tissues, especially for the avascular cornea and lens. The directional transport of ions generates electric fields and currents in those tissues. Applied electric fields affect migration, division and proliferation of ocular cells which are important in homeostasis and healing of the ocular tissues. Abnormalities in any of those aspects may underlie many ocular diseases, for example chronic corneal ulcers, posterior capsule opacity after cataract surgery, and retinopathies. Electric field-inducing cellular responses, termed electrical signaling here, therefore may be an unexpected yet powerful mechanism in regulating ocular cell behavior. Both endogenous electric fields and applied electric fields could be exploited to regulate ocular cells. We aim to briefly describe the physiology of the naturally occurring electrical activities in the corneal, lens, and retinal epithelia, to provide experimental evidence of the effects of electric fields on ocular cell behaviors, and to suggest possible clinical implications. PMID:22020127

  1. An Update on Ocular Surface Epithelial Stem Cells: Cornea and Conjunctiva.

    PubMed

    Ramos, Tiago; Scott, Deborah; Ahmad, Sajjad

    2015-01-01

    The human ocular surface (front surface of the eye) is formed by two different types of epithelia: the corneal epithelium centrally and the conjunctival epithelium that surrounds this. These two epithelia are maintained by different stem cell populations (limbal stem cells for the corneal epithelium and the conjunctival epithelial stem cells). In this review, we provide an update on our understanding of these epithelia and their stem cells systems, including embryology, new markers, and controversy around the location of these stem cells. We also provide an update on the translation of this understanding into clinical applications for the treatment of debilitating ocular surface diseases.

  2. Temporal Dynamics of Ocular Position Dependence of the Initial Human Vestibulo-ocular Reflex

    PubMed Central

    Crane, Benjamin T.; Tian, Junru; Demer, Joseph L.

    2007-01-01

    Purpose While an ideal vestibulo-ocular reflex (VOR) generates ocular rotations compensatory for head motion, during visually guided movements, Listing’s Law (LL) constrains the eye to rotational axes lying in Listing’s Plane (LP). The present study was conducted to explore the recent proposal that the VOR’s rotational axis is not collinear with the head’s, but rather follows a time-dependent strategy intermediate between LL and an ideal VOR. Methods Binocular LPs were defined during visual fixation in eight normal humans. The VOR was evoked by a highly repeatable transient whole-body yaw rotation in darkness at a peak acceleration of 2800 deg/s2. Immediately before rotation, subjects regarded targets 15 or 500 cm distant located at eye level, 20° up, or 20° down. Eye and head responses were compared with LL predictions in the position and velocity domains. Results LP orientation varied both among subjects and between individual subject’s eyes, and rotated temporally with convergence by 5 ± 5° (±SEM). In the position domain, the eye compensated for head displacement even when the head rotated out of LP. Even within the first 20 ms from onset of head rotation, the ocular velocity axis tilted relative to the head axis by 30% ± 8% of vertical gaze position. Saccades increased this tilt. Regardless of vertical gaze position, the ocular rotation axis tilted backward 4° farther in abduction than in adduction. There was also a binocular vertical eye velocity transient and lateral tilt of the ocular axis. Conclusions These disconjugate, short-latency axis perturbations appear intrinsic to the VOR and may have neural or mechanical origins. PMID:16565376

  3. Onset of ocular graft-versus-host disease symptoms after allogeneic hematopoietic stem cell transplantation.

    PubMed

    Shikari, Hasanain; Amparo, Francisco; Saboo, Ujwala; Dana, Reza

    2015-03-01

    To study the factors affecting the time to onset of ocular graft-versus-host disease (GVHD) in patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT). A retrospective chart review of 200 patients with ocular GVHD was performed to evaluate the association between various donor-recipient characteristics and the time to onset of ocular GVHD after allo-HSCT. The median time to onset of chronic ocular GVHD after allo-HSCT was 293 days (range, 26-2308 days). Patients receiving fully human leukocyte antigen (HLA)-matched transplants had a delayed onset of ocular GVHD (median, 294 days) compared with mismatched transplants (219 days; P = 0.029). HLA-matched transplants from related donors had delayed onset of ocular GVHD (307 days) compared with HLA-matched (286 days; P = 0.168) and HLA-mismatched (231 days; P = 0.015) transplants from unrelated donors. Ocular GVHD followed systemic GVHD in 76% of patients but preceded systemic disease in 7%, occurred concurrently in 15%, and was not associated with systemic GVHD in 2% of patients. The time elapsed between the occurrence of systemic and ocular GVHD was significantly longer in matched-related transplants (250 days) than in matched-unrelated transplants (120 days; P = 0.004). The onset of ocular GVHD after allo-HSCT is variable and is influenced by donor-recipient matching characteristics. In the majority of patients with GVHD, ocular involvement follows the occurrence of systemic manifestations; however, importantly, it can also precede or develop independently of systemic disease in a minority of patients. Regular ophthalmic follow-up is recommended after allo-HSCT regardless of concurrent systemic GVHD status.

  4. PRL-3/PTP4A3 phosphatase regulates integrin β1 in adhesion structures during migration of human ocular melanoma cells.

    PubMed

    Foy, Malika; Anézo, Océane; Saule, Simon; Planque, Nathalie

    2017-03-08

    In a previous transcriptomic analysis of 63 ocular melanomas of the uvea, we found that expression of the PRL-3/PTP4A3 gene, encoding a phosphatase that is anchored to the plasma membrane, was associated with the risk of metastasis, and a poor prognosis. We also showed that PRL-3 overexpression in OCM-1 ocular melanoma cells significantly increased cell migration in vitro and invasiveness in vivo, suggesting a direct role for PRL-3 in the metastatic spreading of uveal melanoma. Here, we aimed to identify PRL-3 substrates at the plasma membrane involved in adhesion to the extracellular matrix. We focused on integrin β1, which is the most highly expressed integrin in our cohort of uveal melanomas. We show that preventing PRL-3 anchorage to the plasma membrane i) abolishes PRL-3-induced migration in OCM-1 cells, ii) specifically enhances the spreading of OCM-1 cells overexpressing PRL-3, and iii) favors the maturation of large focal adhesions (FAs) containing integrin β1 on collagen I. Knockdown experiments confirmed integrin β1 involvement in PRL3-induced migration. We identified interactions between PRL-3 and integrin β1, as well as with FAK P-Y397, an auto-activated form of Focal Adhesion Kinase found in FAs. We also show that integrin β1 may be dephosphorylated by PRL-3 in its intracytoplasmic S/T region, an important motif for integrin-mediated cell adhesion. Finally, we observed that PRL-3 regulated the clustering of integrin β1 in FAs on collagen I but not on fibronectin. This work identifies PRL-3 as a new regulator of cell adhesion structures to the extracellular matrix, and further supports PRL-3 as a key actor of metastasis in uveal melanoma, of which molecular mechanisms are still poorly understood.

  5. Ocular surface reconstruction with a tissue-engineered nasal mucosal epithelial cell sheet for the treatment of severe ocular surface diseases.

    PubMed

    Kobayashi, Masakazu; Nakamura, Takahiro; Yasuda, Makoto; Hata, Yuiko; Okura, Shoki; Iwamoto, Miyu; Nagata, Maho; Fullwood, Nigel J; Koizumi, Noriko; Hisa, Yasuo; Kinoshita, Shigeru

    2015-01-01

    Severe ocular surface diseases (OSDs) with severe dry eye can be devastating and are currently some of the most challenging eye disorders to treat. To investigate the feasibility of using an autologous tissue-engineered cultivated nasal mucosal epithelial cell sheet (CNMES) for ocular surface reconstruction, we developed a novel technique for the culture of nasal mucosal epithelial cells expanded ex vivo from biopsy-derived human nasal mucosal tissues. After the protocol, the CNMESs had 4-5 layers of stratified, well-differentiated cells, and we successfully generated cultured epithelial sheets, including numerous goblet cells. Immunohistochemistry confirmed the presence of keratins 3, 4, and 13; mucins 1, 16, and 5AC; cell junction and basement membrane assembly proteins; and stem/progenitor cell marker p75 in the CNMESs. We then transplanted the CNMESs onto the ocular surfaces of rabbits and confirmed the survival of this tissue, including the goblet cells, up to 2 weeks. The present report describes an attempt to overcome the problems of treating severe OSDs with the most severe dry eye by treating them using tissue-engineered CNMESs to supply functional goblet cells and to stabilize and reconstruct the ocular surface. The present study is a first step toward assessing the use of tissue-engineered goblet-cell transplantation of nonocular surface origin for ocular surface reconstruction.

  6. Dental stem cells: a future asset of ocular cell therapy.

    PubMed

    Yam, Gary Hin-Fai; Peh, Gary Swee-Lim; Singhal, Shweta; Goh, Bee-Tin; Mehta, Jodhbir S

    2015-11-10

    Regenerative medicine using patient's own stem cells (SCs) to repair dysfunctional tissues is an attractive approach to complement surgical and pharmacological treatments for aging and degenerative disorders. Recently, dental SCs have drawn much attention owing to their accessibility, plasticity and applicability for regenerative use not only for dental, but also other body tissues. In ophthalmology, there has been increasing interest to differentiate dental pulp SC and periodontal ligament SC (PDLSC) towards ocular lineage. Both can commit to retinal fate expressing eye field transcription factors and generate rhodopsin-positive photoreceptor-like cells. This proposes a novel therapeutic alternative for retinal degeneration diseases. Moreover, as PDLSC shares similar cranial neural crest origin and proteoglycan secretion with corneal stromal keratoctyes and corneal endothelial cells, this offers the possibility of differentiating PDLSC to these corneal cell types. The advance could lead to a shift in the medical management of corneal opacities and endothelial disorders from highly invasive corneal transplantation using limited donor tissue to cell therapy utilizing autologous cells. This article provides an overview of dental SC research and the perspective of utilizing dental SCs for ocular regenerative medicine.

  7. Mouse models of human ocular disease for translational research

    PubMed Central

    Hicks, Wanda L.; Yu, Minzhong; Charette, Jeremy R.; Shi, Lan Ying; Wang, Jieping; Peachey, Neal S.; Nishina, Patsy M.

    2017-01-01

    Mouse models provide a valuable tool for exploring pathogenic mechanisms underlying inherited human disease. Here, we describe seven mouse models identified through the Translational Vision Research Models (TVRM) program, each carrying a new allele of a gene previously linked to retinal developmental and/or degenerative disease. The mutations include four alleles of three genes linked to human nonsyndromic ocular diseases (Aipl1tvrm119, Aipl1tvrm127, Rpgrip1tvrm111, RhoTvrm334) and three alleles of genes associated with human syndromic diseases that exhibit ocular phentoypes (Alms1tvrm102, Clcn2nmf289, Fkrptvrm53). Phenotypic characterization of each model is provided in the context of existing literature, in some cases refining our current understanding of specific disease attributes. These murine models, on fixed genetic backgrounds, are available for distribution upon request and may be useful for understanding the function of the gene in the retina, the pathological mechanisms induced by its disruption, and for testing experimental approaches to treat the corresponding human ocular diseases. PMID:28859131

  8. Comparative ocular microbial communities in humans with and without blepharitis.

    PubMed

    Lee, Se Hee; Oh, Doo Hwan; Jung, Ji Young; Kim, Jae Chan; Jeon, Che Ok

    2012-08-15

    The aims of our study were to compare the ocular microbial communities of humans with and without blepharitis in an attempt to elucidate which microorganisms may cause blepharitis. Bacterial 16S rRNA genes of eyelash and tear samples from seven blepharitis patients and four healthy controls were sequenced using a pyrosequencing method, and their bacterial community structures were compared bioinformatically. Phylotypic analysis demonstrated that eyelash and tear samples had highly diverse bacterial communities with many previously undescribed bacteria. Bacterial communities in eyelash samples from subjects with blepharitis were less diverse than those from healthy controls, while the bacterial communities of tear subjects with blepharitis were more diverse than those of healthy subjects. Statistical analyses using UniFrac and a principle coordinate analysis showed that the bacterial communities of tear samples from subjects with blepharitis were well clustered, regardless of individual, while the bacterial communities of all eyelash samples and healthy tear samples were not well clustered due to high interpersonal variability. Bioinformatic analysis revealed that Propionibacterium, Staphylococcus, Streptophyta, Corynebacterium, and Enhydrobacter were the common ocular bacteria. An increase of Staphylococcus, Streptophyta, Corynebacterium, and Enhydrobacter, and a decrease of Propionibacterium were observed from blepharitis subjects, in terms of the relative abundances. Higher abundances of Streptophyta, Corynebacterium, and Enhydrobacter in blepharitis subjects suggested that human blepharitis might be induced by the infestations of pollens, dusts, and soil particles. These results will provide valuable information for the prevention and treatment of human blepharitis based on ocular microbial flora.

  9. In vitro ocular metabolism and bioactivation of ketoconazole in rat, rabbit and human.

    PubMed

    Cirello, Amanda L; Dumouchel, Jennifer L; Gunduz, Mithat; Dunne, Christine E; Argikar, Upendra A

    2017-04-01

    Oral ketoconazole is clinically administered for treatment of severe cases for fungal keratitis. Pharmacodynamics and efficacy of oral and topical (ocular) ketoconazole have been explored in rabbit. However, metabolism of ketoconazole in the eye in any species is not well explored in any preclinical species or human. An understanding of ocular drug metabolism in the eye is crucial for ocular therapeutics to facilitate the risk assessment and development of potential drug candidates for the clinic. We aimed to investigate the metabolism of ketoconazole in rat, rabbit and human ocular S9 fractions. Metabolism in liver S9 fractions was also studied for a direct comparison. Eleven putative metabolites were identified in the in vitro incubations. Of these metabolites, six were present in rat ocular S9 whereas eight were present in rabbit and human ocular matrices. Metabolic pathways in rabbit and human ocular fractions suggested the formation of reactive intermediates in rabbit and human liver and ocular S9 incubations, which was confirmed with trapping studies. Herein, we report eight human ocular metabolites of ketoconazole for the first time. To the best of our knowledge, this is the first report of ocular metabolic pathways and ocular bioactivation of ketoconazole in preclinical species and human. Copyright © 2016 The Japanese Society for the Study of Xenobiotics. Published by Elsevier Ltd. All rights reserved.

  10. Porcine retinal cell line VIDO R1 and Chlamydia suis to modelize ocular chlamydiosis.

    PubMed

    Käser, Tobias; Cnudde, Thomas; Hamonic, Glenn; Rieder, Meghanne; Pasternak, J Alex; Lai, Ken; Tikoo, Suresh K; Wilson, Heather L; Meurens, François

    2015-08-15

    Human ocular Chlamydia trachomatis infections can lead to trachoma, the major cause of infectious blindness worldwide. Trachoma control strategies are very helpful but logistically challenging, and a trachoma vaccine is needed but not available. Pigs are a valuable large animal model for various immunological questions and could facilitate the study of human ocular chlamydial infections. In addition, a recent study identified the zoonotic potential of Chlamydia suis, the natural pathogen of pigs. In terms of the One Health Initiative, understanding the host-pathogen-interactions and finding a vaccine for porcine chlamydia infections would also benefit human health. Thus, we infected the porcine retinal cell line VIDO R1 with C. suis and analyzed the chlamydial life cycle and the innate immune response of the infected cells. Our results indicate that C. suis completes its life cycle in VIDO R1 cells within 48 h, comparable to C. trachomatis in humans. C. suis infection of VIDO R1 cells led to increased levels of various innate immune mediators like pathogen recognition receptors, cytokines and chemokines including IL6, TNFα, and MMP9, also most relevant in human C. trachomatis infections. These results illustrate the first steps in the host-pathogen-interactions of ocular C. suis infections in pigs and show their similarity to C. trachomatis infections in humans, justifying further testing of pigs as an animal model for human trachoma. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. EcPV2 DNA in equine squamous cell carcinomas and normal genital and ocular mucosa.

    PubMed

    Vanderstraeten, Eva; Bogaert, Lies; Bravo, Ignacio G; Martens, Ann

    2011-01-27

    Squamous cell carcinoma (SCC) represents the most common malignant tumour of the eye and external genitals in horses. Comparable to humans, papillomaviruses (PV) have been proposed as etiological agents of cancer in horses and recently, Equine papillomavirus type 2 (EcPV2) has been identified in genital SCCs. Hitherto it had never been demonstrated in ocular SCCs. The first goal of this study was to determine the prevalence of EcPV2 DNA in tissue samples from equine genital and ocular SCCs, genital papillomas and penile intraepithelial neoplasia (PIN) lesions, using EcPV2-specific PCR. The second goal was to investigate the possibility of latent EcPV2 infection in the genital and ocular mucosa of healthy horses on swabs obtained from the eye, penis, vulvovaginal region and cervix. EcPV2 DNA was detected in all genital SCCs (17/17), genital papillomas (8/8), PIN lesions (11/11) and ocular SCCs (9/9). In healthy horses, EcPV2 DNA was detected in 43% (17/40) of penile swabs, 53% (9/17) of vulvovaginal swabs, 47% (8/17) of cervical swabs and 57% (32/56) of ocular swabs. This study confirms the presence of EcPV2 DNA in equine genital SCCs. Moreover, we demonstrate for the first time its involvement in other genital lesions and in ocular SCCs and latent EcPV2 infections in normal genital (including cervical) and ocular equine mucosa. The close relatives of EcPV2 are associated to cutaneous lesions, and this virus is not related to high-risk human papillomaviruses causing cervical cancer. Thus, similar viral tropism does not imply close evolutionary relationship. Copyright © 2010 Elsevier B.V. All rights reserved.

  12. Demodex species in human ocular disease: new clinicopathological aspects.

    PubMed

    Nicholls, Stephen G; Oakley, Carmen L; Tan, Andrea; Vote, Brendan J

    2017-02-01

    Demodex brevis and Demodex folliculorum are likely ubiquitous organisms associated with human eyelashes. However, they have also been implicated in the pathogenesis of external ocular diseases. This article reviews the current literature in regards to life cycle, morphology, pathogenesis and treatment of underlying Demodex spp. infestation and outlines the previously undescribed in vivo behaviour of the mites. Images were obtained from the epilation of lashes from 404 patients seen in clinical practice. Epilated lashes were placed on a microscope slide which had been coated with optically clear hypromellose/carbomer gel (Genteal gel, Novartis pharmaceuticals corporation, East Hanover, New Jersey). Adults were identified with either dark field or standard transmission microscopy at 40-100×. Eggs and other life-cycle stages were examined at 250× magnification, with transmission microscopy giving the best image resolution. The life cycle of the mite has been reviewed and simplified according to clinical observations. Clinical signs suggestive of underlying Demodex spp. infestation have been described, and their pathogenesis was explained based on the micrographic digital images obtained. The problem of symptomatic Demodex spp. disease likely reflects an imbalance in the external ocular ecology; however, the role of Demodex spp. as a commensal should not be overlooked. Treatment should not be aimed at total eradication of the mite but rather restoring the ocular ecology to a balanced state. By revisiting the life cycle of the mite, we can identify areas where possible intervention may be effective.

  13. Transplant related ocular surface disorders: Advanced techniques for ocular surface rehabilitation after ocular complications secondary to hematopoietic stem cell transplantation.

    PubMed

    Stahl, Erin D; Mahomed, Faheem; Hans, Amneet K; Dalal, Jignesh D

    2016-05-01

    HSCT has been linked to the development of an assortment of ocular surface complications with the potential to lead to permanent visual impairment if left untreated or if not treated early in the course of disease. Strategies for therapy include maintenance of lubrication and tear preservation, prevention of evaporation, decreasing inflammation, and providing epithelial support. The ultimate aim of treatment is to prevent permanent ocular sequelae through prompt ophthalmology consultation and the use of advanced techniques for ocular surface rehabilitation. We describe several rehabilitation options of ocular surface complications occurring secondarily during the post-HSCT course. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Characterization of full-length recombinant human Proteoglycan 4 as an ocular surface boundary lubricant.

    PubMed

    Samsom, Michael L; Morrison, Sheila; Masala, Nemanja; Sullivan, Benjamin D; Sullivan, David A; Sheardown, Heather; Schmidt, Tannin A

    2014-10-01

    Proteoglycan 4 (PRG4, or lubricin) is a lubricating mucin-like glycoprotein recently discovered at the ocular surface, where it functions as a boundary lubricant and appears to play a protective role. Recent technological advances have enabled abundant expression of full-length recombinant human PRG4 (rhPRG4). The objectives of this study were to 1) biochemically characterize the gross structure and glycosylations of full-length rhPRG4, and 2) assess the ocular surface boundary lubricating ability of rhPRG4 at both human cornea-eyelid and human cornea-polydimethylsiloxane (PDMS) biointerfaces. rhPRG4 expressed by a Chinese hamster ovary cell line was characterized and compared to native bovine PRG4 by SDS-PAGE western blotting, and protein identity was assessed by tandem mass spectrometry (MS/MS). Human corneas were articulated against PDMS or human eyelids, at effective sliding velocities of 0.3-30 mm/s under physiological loads of ∼15 kPa, to assess and compare the ocular lubricating ability of rhPRG4 to PRG4. Samples were tested serially in PRG4, rhPRG4 (both 300 μg/ml), then saline. Western blotting indicated that rhPRG4 had immunoreactivity at the appropriate apparent molecular weight, and possessed O-linked glycosylation consistent with that of PRG4. rhPRG4 protein identity was confirmed by MS/MS. Both PRG4 and rhPRG4 significantly, and similarly, reduced friction compared to saline at both human cornea - PDMS and human cornea-eyelid biointerfaces. In conclusion, the rhPRG4 studied here demonstrated appropriate higher order structure, O-linked glycosylations, and ocular surface boundary lubricating. Purified rhPRG4 may have clinical utility as a topical treatment of dry eye disease or contact lens biomaterial coating to promote more comfortable wear. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Protective effects of fluoroquinolones on UV-induced damage of cultured ocular cell lines.

    PubMed

    Nishida, Takashi; Kuse, Yoshiki; Mochizuki, Kiyofumi; Shimazawa, Masamitsu; Yamamoto, Tetsuya; Hara, Hideaki

    2017-07-05

    Although the fluoroquinolones have strong antibacterial effects, some of them also have adverse ocular effects such as diplopia, uveitis, optic neuropathy, and retinal detachment. The purpose of this study was to determine whether low concentrations of fluoroquinolones can lessen the cytotoxic effects of ultraviolet (UV) light on different kinds of cultured ocular cells. We studied cultured human corneal endothelial cells (HCECs), a retinal ganglion cell line (RGC-5), a mouse-derived photoreceptor cell line (661W), a human adult retinal pigment epithelial cell line (ARPE-19), primary retinal cells, and primary human RPE cells. Levofloxacin, ciprofloxacin, and clinafloxacin were selected as the fluoroquinolones to test. The viabilities of the 661W, ARPE-19, and hRPE cells were assessed by Cell Counting Kit-8, and that of HCECs, 661W cells, and ARPE-19 cells by double fluorescent staining with Hoechst 33342 and propidium iodide (PI). Damage of retinal primary culture cells was assessed by immunostaining. Intracellular production of reactive oxygen species was measured in ARPE-19 cells by CM-H2DCFDA after UV light exposure. An activation of caspase by UV light in ARPE-19 cells was detected with a caspase-3/7 assay kit. UV exposure increased the number of dead cells, and the three fluoroquinolones tested suppressed this increase. Fluoroquinolones also protected the cells against the hydroxyperoxide (H2O2)-induced cell damage. Moreover, the fluoroquinolones decreased the production of reactive oxygen species and the activity of caspase-3/7, and low concentrations of fluoroquinolones reduced the oxidative stress in cultured ocular cell lines. We conclude that fluoroquinolones may have protective effects in these cells against UV exposure. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Quantitative reflection spectroscopy at the human ocular fundus

    NASA Astrophysics Data System (ADS)

    Hammer, Martin; Schweitzer, Dietrich

    2002-01-01

    A new model of the reflection of the human ocular fundus on the basis of the adding-doubling method, an approximate solution of the radiative transport equation, is described. This model enables the calculation of the concentrations of xanthophyll in the retina, of melanin in the retinal pigment epithelium and the choroid, and of haemoglobin in the choroid from fundus reflection spectra. The concentration values found in 12 healthy subjects are in excellent agreement with published data. In individual cases of pathologic fundus alterations, possible benefits to the ophthalmologic diagnostics are demonstrated.

  17. Ocular blood flow measurements in healthy human myopic eyes.

    PubMed

    Benavente-Pérez, Alexandra; Hosking, Sarah L; Logan, Nicola S; Broadway, David C

    2010-11-01

    To evaluate the haemodynamic features of young healthy myopes and emmetropes, in order to ascertain the perfusion profile of human myopia and its relationship with axial length prior to reaching a degenerative state. The retrobulbar, microretinal and pulsatile ocular blood flow (POBF) of one eye of each of twenty-two high myopes (N = 22, mean spherical equivalent (MSE) ≤-5.00D), low myopes (N = 22, MSE-1.00 to-4.50D) and emmetropes (N = 22, MSE ± 0.50D) was analyzed using color Doppler Imaging, Heidelberg retinal flowmetry and ocular blood flow analyser (OBF) respectively. Intraocular pressure, axial length (AL), systemic blood pressure, and body mass index were measured. When compared to the emmetropes and low myopes, the AL was greater in high myopia (p < 0.0001). High myopes showed higher central retinal artery resistance index (CRA RI) (p = 0.004), higher peak systolic to end diastolic velocities ratio (CRA ratio) and lower end diastolic velocity (CRA EDv) compared to low myopes (p = 0.014, p = 0.037). Compared to emmetropes, high myopes showed lower OBFamplitude (OBFa) (p = 0.016). The POBF correlated significantly with the systolic and diastolic blood velocities of the CRA (p = 0.016, p = 0.036). MSE and AL correlated negatively with OBFa (p = 0.03, p = 0.003), OBF volume (p = 0.02, p < 0.001), POBF (p = 0.01, p < 0.001) and positively with CRA RI (p = 0.007, p = 0.05). High myopes exhibited significantly reduced pulse amplitude and CRA blood velocity, the first of which may be due to an OBF measurement artefact or real decreased ocular blood flow pulsatility. Axial length and refractive error correlated moderately with the ocular pulse and with the resistance index of the CRA, which in turn correlated amongst themselves. It is hypothesized that the compromised pulsatile and CRA haemodynamics observed in young healthy myopes is an early feature of the decrease in ocular blood flow

  18. Cell culture models of the human cornea - a comparative evaluation of their usefulness to determine ocular drug absorption in-vitro.

    PubMed

    Reichl, Stephan

    2008-03-01

    Cell culture models of the cornea are continually developed to replace the isolated animal cornea for transcorneal drug absorption studies. The aim of this study was to determine and compare epithelial tightness and permeability of currently available corneal cell culture models to avoid interlaboratory variability and to assess their usefulness for in-vitro permeation studies. Pure epithelial cell culture models (CEPI, SIRC and HCE-T cell lines), primary cultures of human corneal epithelium (HCEpiC) and the two commercially available models (RHC and Epiocular), as well as organotypic human cornea constructs (HCC, HCC-HCE-T), were investigated and data were compared with those obtained from the excised bovine cornea. Barrier properties were assessed by measurements of transepithelial electrical resistance (TEER) and permeability of three passively absorbed substances (mannitol, testosterone and timolol maleate) with different physico-chemical properties. TEER experiments revealed weak barrier functions for all of the investigated epithelial models (cell line. Transport studies confirmed TEER results insofar that models showing low TEER values also had higher permeation rates in comparison with the excised bovine cornea. However, models based on HCE-T cells demonstrated similar barrier properties to isolated corneal tissue. The corneal models investigated in our laboratory show clear differences in epithelial barrier function. In-vitro systems comprising the HCE-T cell line seem to be most appropriate to replace excised animal cornea for assessing corneal permeability.

  19. The chemokine receptor CCR7 expressed by dendritic cells: a key player in corneal and ocular surface inflammation.

    PubMed

    Saban, Daniel R

    2014-04-01

    Dendritic cells (DCs) are highly potent stimulators of the immune system, and their contribution as such to the pathogenesis of corneal and ocular surface inflammatory disease has been well established. These vigorous antigen-presenting cells are reliant upon their effective migration from peripheral tissues (e.g., those of the ocular surface) to the lymphoid organs, where immune responses are triggered and can then cause disease. The chemokine receptor CCR7 expressed on DCs has emerged as the master mediator of this highly complex migratory process, and thus it is important in causing corneal and ocular surface inflammation. Furthermore, CCR7 has received considerable attention as a potential therapeutic target, as topically instilled antagonists of this receptor are quite effective therapeutically in a mouse model of ocular allergy. These findings and more are reviewed in the current article. In addition, the understanding regarding CCR7 function in mice and humans, and the biology of DCs that populate the ocular surface are also detailed herein. The involvement of DCs and their expression of CCR7 in corneal and ocular surface diseases such as in ocular allergy, dry eye disease, immune rejection and more, are also reviewed here.

  20. Ocular stem cells: a status update!

    PubMed

    Dhamodaran, Kamesh; Subramani, Murali; Ponnalagu, Murugeswari; Shetty, Reshma; Das, Debashish

    2014-01-01

    Stem cells are unspecialized cells that have been a major focus of the field of regenerative medicine, opening new frontiers and regarded as the future of medicine. The ophthalmology branch of the medical sciences was the first to directly benefit from stem cells for regenerative treatment. The success stories of regenerative medicine in ophthalmology can be attributed to its accessibility, ease of follow-up and the eye being an immune-privileged organ. Cell-based therapies using stem cells from the ciliary body, iris and sclera are still in animal experimental stages but show potential for replacing degenerated photoreceptors. Limbal, corneal and conjunctival stem cells are still limited for use only for surface reconstruction, although they might have potential beyond this. Iris pigment epithelial, ciliary body epithelial and choroidal epithelial stem cells in laboratory studies have shown some promise for retinal or neural tissue replacement. Trabecular meshwork, orbital and sclera stem cells have properties identical to cells of mesenchymal origin but their potential has yet to be experimentally determined and validated. Retinal and retinal pigment epithelium stem cells remain the most sought out stem cells for curing retinal degenerative disorders, although treatments using them have resulted in variable outcomes. The functional aspects of the therapeutic application of lenticular stem cells are not known and need further attention. Recently, embryonic stem cell-derived retinal pigment epithelium has been used for treating patients with Stargardts disease and age-related macular degeneration. Overall, the different stem cells residing in different components of the eye have shown some success in clinical and animal studies in the field of regenerative medicine.

  1. Ocular stem cells: a status update!

    PubMed Central

    2014-01-01

    Stem cells are unspecialized cells that have been a major focus of the field of regenerative medicine, opening new frontiers and regarded as the future of medicine. The ophthalmology branch of the medical sciences was the first to directly benefit from stem cells for regenerative treatment. The success stories of regenerative medicine in ophthalmology can be attributed to its accessibility, ease of follow-up and the eye being an immune-privileged organ. Cell-based therapies using stem cells from the ciliary body, iris and sclera are still in animal experimental stages but show potential for replacing degenerated photoreceptors. Limbal, corneal and conjunctival stem cells are still limited for use only for surface reconstruction, although they might have potential beyond this. Iris pigment epithelial, ciliary body epithelial and choroidal epithelial stem cells in laboratory studies have shown some promise for retinal or neural tissue replacement. Trabecular meshwork, orbital and sclera stem cells have properties identical to cells of mesenchymal origin but their potential has yet to be experimentally determined and validated. Retinal and retinal pigment epithelium stem cells remain the most sought out stem cells for curing retinal degenerative disorders, although treatments using them have resulted in variable outcomes. The functional aspects of the therapeutic application of lenticular stem cells are not known and need further attention. Recently, embryonic stem cell-derived retinal pigment epithelium has been used for treating patients with Stargardts disease and age-related macular degeneration. Overall, the different stem cells residing in different components of the eye have shown some success in clinical and animal studies in the field of regenerative medicine. PMID:25158127

  2. Initiation of the human heave linear vestibulo-ocular reflex.

    PubMed

    Crane, Benjamin T; Tian, Junru; Wiest, Gerald; Demer, Joseph L

    2003-01-01

    The linear vestibulo-ocular reflex (LVOR) was studied in eight normal human subjects of average age 24+/-5 years. Subjects underwent a sudden heave (mediolateral) translation delivered by a pneumatic servo-driven chair with a peak acceleration of 0.5 g while viewing earth-fixed targets at 15, 25, 50, and 200 cm. Stimuli were provided both with targets continuously visible or extinguished just prior to motion. Cancellation was tested using chair-fixed targets at each viewing distance. Eye movements were recorded using binocular magnetic search coils. Head translation was measured using a linear accelerometer attached to the upper teeth, to which also was attached a magnetic search coil verifying absence of head rotation. Vergence angles achieved by all subjects were appropriate to interpupillary distance and target distance. Heave translations evoked horizontal ocular rotations in the opposite direction following a brief latency. Latency of the LVOR was determined by automated algorithms based on identification of times when eye position and head acceleration exceeded three standard deviations (SDs) of baseline noise, and was corrected for differing transducer delays. Mean LVOR latency was 30+/-16 ms (mean +/- SD), range 12-53 ms. Slow phase LVOR amplitude was greater for near and less for more distant targets, although all observed responses were suboptimal. Measured 100 ms after head translation onset, mean response was 20% of ideal for the target at 15 cm, 22% at 25 cm, 31% at 50 cm, and 53% at 200 cm. Mean latency was significantly longer than the previously reported values for both the human angular VOR and the monkey LVOR, and had significant inverse correlation with response magnitude. The relatively longer latency of the human LVOR than angular VOR may be tailored to match human head movement dynamics.

  3. IGF‐1 Signaling Plays an Important Role in the Formation of Three‐Dimensional Laminated Neural Retina and Other Ocular Structures From Human Embryonic Stem Cells

    PubMed Central

    Mellough, Carla B.; Collin, Joseph; Khazim, Mahmoud; White, Kathryn; Sernagor, Evelyne; Steel, David H. W.

    2015-01-01

    Abstract We and others have previously demonstrated that retinal cells can be derived from human embryonic stem cells (hESCs) and induced pluripotent stem cells under defined culture conditions. While both cell types can give rise to retinal derivatives in the absence of inductive cues, this requires extended culture periods and gives lower overall yield. Further understanding of this innate differentiation ability, the identification of key factors that drive the differentiation process, and the development of clinically compatible culture conditions to reproducibly generate functional neural retina is an important goal for clinical cell based therapies. We now report that insulin‐like growth factor 1 (IGF‐1) can orchestrate the formation of three‐dimensional ocular‐like structures from hESCs which, in addition to retinal pigmented epithelium and neural retina, also contain primitive lens and corneal‐like structures. Inhibition of IGF‐1 receptor signaling significantly reduces the formation of optic vesicle and optic cups, while exogenous IGF‐1 treatment enhances the formation of correctly laminated retinal tissue composed of multiple retinal phenotypes that is reminiscent of the developing vertebrate retina. Most importantly, hESC‐derived photoreceptors exhibit advanced maturation features such as the presence of primitive rod‐ and cone‐like photoreceptor inner and outer segments and phototransduction‐related functional responses as early as 6.5 weeks of differentiation, making these derivatives promising candidates for cell replacement studies and in vitro disease modeling. Stem Cells 2015;33:2416–2430 PMID:25827910

  4. A simplified technique for in situ excision of cornea and evisceration of retinal tissue from human ocular globe.

    PubMed

    Parekh, Mohit; Ferrari, Stefano; Di Iorio, Enzo; Barbaro, Vanessa; Camposampiero, Davide; Karali, Marianthi; Ponzin, Diego; Salvalaio, Gianni

    2012-06-12

    Enucleation is the process of retrieving the ocular globe from a cadaveric donor leaving the rest of the globe undisturbed. Excision refers to the retrieval of ocular tissues, especially cornea, by cutting it separate from the ocular globe. Evisceration is the process of removing the internal organs referred here as retina. The ocular globe consists of the cornea, the sclera, the vitreous body, the lens, the iris, the retina, the choroid, muscles etc (Suppl. Figure 1). When a patient is suffering from corneal damage, the cornea needs to be removed and a healthy one must be transplanted by keratoplastic surgeries. Genetic disorders or defects in retinal function can compromise vision. Human ocular globes can be used for various surgical procedures such as eye banking, transplantation of human cornea or sclera and research on ocular tissues. However, there is little information available on human corneal and retinal excision, probably due to the limited accessibility to human tissues. Most of the studies describing similar procedures are performed on animal models. Research scientists rely on the availability of properly dissected and well-conserved ocular tissues in order to extend the knowledge on human eye development, homeostasis and function. As we receive high amount of ocular globes out of which approximately 40% (Table 1) of them are used for research purposes, we are able to perform huge amount of experiments on these tissues, defining techniques to excise and preserve them regularly. The cornea is an avascular tissue which enables the transmission of light onto the retina and for this purpose should always maintain a good degree of transparency. Within the cornea, the limbus region, which is a reservoir of the stem cells, helps the reconstruction of epithelial cells and restricts the overgrowth of the conjunctiva maintaining corneal transparency and clarity. The size and thickness of the cornea are critical for clear vision, as changes in either of them

  5. Ocular Adverse Events Associated with Antibody–Drug Conjugates in Human Clinical Trials

    PubMed Central

    Miller, Paul E.; Mannis, Mark J.

    2015-01-01

    Abstract This article reviews ocular adverse events (AEs) reported in association with administration of antibody–drug conjugates (ADCs) in human clinical trials. References reporting ocular toxicity or AEs associated with ADCs were collected using online publication searches. Articles, abstracts, or citations were included if they cited ocular toxicities or vision-impairing AEs with a confirmed or suspected association with ADC administration. Twenty-two references were found citing ocular or vision-impairing AEs in association with ADC administration. All references reported use of ADCs in human clinical trials for treatment of various malignancies. The molecular target and cytotoxic agent varied depending on the ADC used. Ocular AEs affected a diversity of ocular tissues. The most commonly reported AEs involved the ocular surface and included blurred vision, dry eye, and corneal abnormalities (including microcystic corneal disease). Most ocular AEs were not severe (≤ grade 2) or dose limiting. Clinical outcomes were not consistently reported, but when specified, most AEs improved or resolved with cessation of treatment or with ameliorative therapy. A diverse range of ocular AEs are reported in association with administration of ADCs for the treatment of cancer. The toxicologic mechanism(s) and pathogenesis of such events are not well understood, but most are mild in severity and reversible. Drug development and medical professionals should be aware of the clinical features of these events to facilitate early recognition and intervention in the assessment of preclinical development programs and in human clinical trials. PMID:26539624

  6. Estimation of projection errors in human ocular fundus imaging.

    PubMed

    Doelemeyer, A; Petrig, B L

    2000-03-01

    Photogrammetric analysis of features in human ocular fundus images is affected by various sources of errors, for example aberrations of the camera and eye optics. Another--usually disregarded--type of distortion arises from projecting the near spherical shape of the fundus onto a planar imaging device. In this paper we quantify such projection errors based on geometrical analysis of the reduced model eye imaged by a pinhole camera. The projection error found near the edge of a 50 degrees fundus image is 24%. In addition, the influence of axial ametropia is investigated for both myopia and hyperopia. The projection errors found in hyperopia are similar to those in emmetropia, but decrease in myopia. Spherical as well as ellipsoidal eye shapes were used in the above calculation and their effect was compared. Our results suggest that the simple spherical eye shape is sufficient for correcting projection distortions within a range of ametropia from -5 to +5 diopters.

  7. Development of gene and stem cell therapy for ocular neurodegeneration

    PubMed Central

    Zhang, Jing-Xue; Wang, Ning-Li; Lu, Qing-Jun

    2015-01-01

    Retinal degenerative diseases pose a serious threat to eye health, but there is currently no effective treatment available. Recent years have witnessed rapid development of several cutting-edge technologies, such as gene therapy, stem cell therapy, and tissue engineering. Due to the special features of ocular structure, some of these technologies have been translated into ophthalmological clinic practice with fruitful achievements, setting a good example for other fields. This paper reviews the development of the gene and stem cell therapies in ophthalmology. PMID:26086019

  8. Epidemic Keratoconjunctivitis-Causing Adenoviruses Induce MUC16 Ectodomain Release To Infect Ocular Surface Epithelial Cells.

    PubMed

    Menon, Balaraj B; Zhou, Xiaohong; Spurr-Michaud, Sandra; Rajaiya, Jaya; Chodosh, James; Gipson, Ilene K

    2016-01-01

    Human adenoviruses (HAdV), species D in particular (HAdV-D), are frequently associated with epidemic keratoconjunctivitis (EKC). Although the infection originates at the ocular surface epithelium, the mechanisms by which HAdV-Ds bypass the membrane-associated mucin (MAM)-rich glycocalyx of the ocular surface epithelium to trigger infection and inflammation remain unknown. Here, we report that an EKC-causing adenovirus (HAdV-D37), but not a non-EKC-causing one (HAdV-D19p), induces ectodomain release of MUC16-a MAM with barrier functions at the ocular surface-from cultured human corneal and conjunctival epithelial cells. HAdV-D37, but not HAdV-D19p, is also found to decrease the glycocalyx barrier function of corneal epithelial cells, as determined by rose bengal dye penetrance assays. Furthermore, results from quantitative PCR (qPCR) amplification of viral genomic DNA using primers specific to a conserved region of the E1B gene show that, in comparison to infection by HAdV-D19p, infection by HAdV-D37 is significantly increased in corneal epithelial cells. Collectively, these results point to a MUC16 ectodomain release-dependent mechanism utilized by the EKC-causing HAdV-D37 to initiate infection at the ocular surface. These findings are important in terms of understanding the pathogenesis of adenoviral keratoconjunctivitis. Similar MAM ectodomain release mechanisms may be prevalent across other mucosal epithelia in the body (e.g., the airway epithelium) that are prone to adenoviral infection. IMPORTANCE Human adenoviruses (HAdVs) are double-stranded DNA viruses that cause infections across all mucosal tissues in the body. At the ocular surface, HAdVs cause keratoconjunctivitis (E. Ford, K. E. Nelson, and D. Warren, Epidemiol Rev 9:244-261, 1987, and C. M. Robinson, D. Seto, M. S. Jones, D. W. Dyer, and J. Chodosh, Infect Genet Evol 11:1208-1217, 2011, doi:10.1016/j.meegid.2011.04.031)-a highly contagious infection that accounts for nearly 60% of conjunctivitis cases

  9. Ocular findings in human immunodeficiency virus patients in Washington, DC.

    PubMed

    Kaleem, Mona A; Ramsahai, Shweta; Del Fierro, Katrina; Rasul, Samad; Onumah, Chavon; Lerebours, Valerie; Gajjala, Jhansi; Copeland, Robert A; Jones, Leslie S

    2012-04-01

    The purpose of the study was to determine the prevalence of ocular diseases in human immunodeficiency virus (HIV) patients in Washington, DC in the era of highly active antiretroviral therapy (HAART). This was a cross-sectional study of patients with HIV who were seen by the ophthalmology consultation service between September 2003 and May 2011 at a single academic institution in Washington, DC. Medical history and ophthalmic findings were reviewed. Patients with complete laboratory data dated within 3 months of their presenting eye examination were included. Descriptive statistics were performed. The records of 151 patients were included in the final analysis. All patients had complete laboratory data dated within 3 months of their presenting eye examination. Sixty-eight (45 %) patients and fifty-eight (50 %) of those with a diagnosis of acquired immune deficiency syndrome (AIDS) were diagnosed with an HIV-related ophthalmic disease. The leading anterior segment disease was herpes zoster ophthalmicus and the leading posterior segment disease was HIV retinopathy. Of the 151 included patients, 78 (52 %) were receiving HAART at the time of the examination. Thirty-one (42 %) of those not receiving HAART were diagnosed with an HIV-related ophthalmic disease. In this study, we find that the overall prevalence of ocular disease has decreased since the introduction of HAART. However, HIV patients continue to be predisposed to developing ophthalmic disease at higher rates than the general population. Visual dysfunction remains an important source of morbidity in HIV patients, particularly in those with AIDS. Measures for improvement include increased communication between infectious disease specialists and ophthalmologists to ensure adherence to HAART and routine eye examinations.

  10. Ocular input for human melatonin regulation: relevance to breast cancer

    NASA Technical Reports Server (NTRS)

    Glickman, Gena; Levin, Robert; Brainard, George C.

    2002-01-01

    The impact of breast cancer on women across the world has been extensive and severe. As prevalence of breast cancer is greatest in industrialized regions, exposure to light at night has been proposed as a potential risk factor. This theory is supported by the epidemiological observations of decreased breast cancer in blind women and increased breast cancer in women who do shift-work. In addition, human, animal and in vitro studies which have investigated the melatonin-cancer dynamic indicate an apparent relationship between light, melatonin and cancer, albeit complex. Recent developments in understanding melatonin regulation by light in humans are examined, with particular attention to factors that contribute to the sensitivity of the light-induced melatonin suppression response. Specifically, the role of spectral characteristics of light is addressed, and recent relevant action spectrum studies in humans and other mammalian species are discussed. Across five action spectra for circadian and other non-visual responses, a peak sensitivity between 446-484 nm was identified. Under highly controlled exposure circumstances, less than 1 lux of monochromatic light elicited a significant suppression of nocturnal melatonin. In view of the possible link between light exposure, melatonin suppression and cancer risk, it is important to continue to identify the basic related ocular physiology. Visual performance, rather than circadian function, has been the primary focus of architectural lighting systems. It is now necessary to reevaluate lighting strategies, with consideration of circadian influences, in an effort to maximize physiological homeostasis and health.

  11. Ocular input for human melatonin regulation: relevance to breast cancer.

    PubMed

    Glickman, Gena; Levin, Robert; Brainard, George C

    2002-07-01

    The impact of breast cancer on women across the world has been extensive and severe. As prevalence of breast cancer is greatest in industrialized regions, exposure to light at night has been proposed as a potential risk factor. This theory is supported by the epidemiological observations of decreased breast cancer in blind women and increased breast cancer in women who do shift-work. In addition, human, animal and in vitro studies which have investigated the melatonin-cancer dynamic indicate an apparent relationship between light, melatonin and cancer, albeit complex. Recent developments in understanding melatonin regulation by light in humans are examined, with particular attention to factors that contribute to the sensitivity of the light-induced melatonin suppression response. Specifically, the role of spectral characteristics of light is addressed, and recent relevant action spectrum studies in humans and other mammalian species are discussed. Across five action spectra for circadian and other non-visual responses, a peak sensitivity between 446-484 nm was identified. Under highly controlled exposure circumstances, less than 1 lux of monochromatic light elicited a significant suppression of nocturnal melatonin. In view of the possible link between light exposure, melatonin suppression and cancer risk, it is important to continue to identify the basic related ocular physiology. Visual performance, rather than circadian function, has been the primary focus of architectural lighting systems. It is now necessary to reevaluate lighting strategies, with consideration of circadian influences, in an effort to maximize physiological homeostasis and health.

  12. Ocular input for human melatonin regulation: relevance to breast cancer

    NASA Technical Reports Server (NTRS)

    Glickman, Gena; Levin, Robert; Brainard, George C.

    2002-01-01

    The impact of breast cancer on women across the world has been extensive and severe. As prevalence of breast cancer is greatest in industrialized regions, exposure to light at night has been proposed as a potential risk factor. This theory is supported by the epidemiological observations of decreased breast cancer in blind women and increased breast cancer in women who do shift-work. In addition, human, animal and in vitro studies which have investigated the melatonin-cancer dynamic indicate an apparent relationship between light, melatonin and cancer, albeit complex. Recent developments in understanding melatonin regulation by light in humans are examined, with particular attention to factors that contribute to the sensitivity of the light-induced melatonin suppression response. Specifically, the role of spectral characteristics of light is addressed, and recent relevant action spectrum studies in humans and other mammalian species are discussed. Across five action spectra for circadian and other non-visual responses, a peak sensitivity between 446-484 nm was identified. Under highly controlled exposure circumstances, less than 1 lux of monochromatic light elicited a significant suppression of nocturnal melatonin. In view of the possible link between light exposure, melatonin suppression and cancer risk, it is important to continue to identify the basic related ocular physiology. Visual performance, rather than circadian function, has been the primary focus of architectural lighting systems. It is now necessary to reevaluate lighting strategies, with consideration of circadian influences, in an effort to maximize physiological homeostasis and health.

  13. Primary invasive ocular squamous cell carcinoma in a horse.

    PubMed

    Kaps, Simone; Richter, Marianne; Philipp, Martin; Bart, Madeleine; Eule, Corinna; Spiess, Bernhard M

    2005-01-01

    A 12-year-old Haflinger gelding was presented to the veterinary medical teaching hospital of the University of Zurich with a light-pink raised mass on the temporal limbus and conjunctiva of the left eye. Squamous cell carcinoma was confirmed histologically after keratectomy and cryotherapy. Seven months later, a smooth pink, progressively enlarging mass was observed within the cornea of the left eye. Ultrasonographically, the mass was not only infiltrating the corneal stroma but seemed to protrude into the anterior chamber. The globe was surgically removed and submitted for pathology. A histologic diagnosis of corneal ocular squamous cell carcinoma with deep stromal invasion, infiltration of the uveoscleral meshwork and iridocorneal angle and resulting intraocular extension was made. This is the first detailed description of a limbal squamous cell carcinoma with invasion into the cornea and uvea in the horse.

  14. The effect of postmortem time on the RNA quality of human ocular tissues

    PubMed Central

    Kim, Byung-Jin; Sprehe, Nicholas; Morganti, Ashley; Wordinger, Robert J.

    2013-01-01

    Purpose Profiling gene expression in human ocular tissues provides invaluable information for understanding ocular biology and investigating numerous ocular diseases. Accurate measurement of gene expression requires high-quality RNA, which often is a challenge with postmortem ocular tissues. Methods We examined the effect of various death to preservation (DP) times on the RNA quality of ten different ocular tissues. We used 16 eyes from eight different human donors. The eyes were preserved immediately in RNAlater or preserved after initial storage at 4 °C to create a range of DP times from 2 to 48 h. Ten ocular tissues were dissected from each eye. After total RNA was extracted from each dissected ocular tissue, the RNA integrity number (RIN) was determined using an Agilent Bioanalyzer. Results The RIN values from corneal and trabecular meshwork tissues were significantly (p<0.05) higher than those from the ciliary body at an earlier DP time (<6 h), but were not different among all tissues after 8 h. Interestingly, the RIN values from non-vascularized tissues were significantly (p=0.0002) higher than those from vascularized ocular tissues at early DP times (<6 h). The RIN value from the cornea was significantly (p<0.05) higher at short DP times compared to longer DP times. The RIN values from corneal tissues were significantly correlated to DP time according to regression analysis (p<0.05). Conclusions In this study, we determined RNA quality from postmortem ocular tissues with various DP times. Our results emphasize the need for rapid preservation and processing of postmortem human donor eye tissues, especially for vascularized ocular tissues. PMID:23805035

  15. Expression of MUC5AC in ocular surface epithelial cells using cationized gelatin nanoparticles.

    PubMed

    Konat Zorzi, Giovanni; Contreras-Ruiz, Laura; Párraga, Jenny Evelin; López-García, Antonio; Romero Bello, Rafael; Diebold, Yolanda; Seijo, Begoña; Sánchez, Alejandro

    2011-10-03

    Decreased production of the mucin MUC5AC in the eye is related to several pathological conditions, including dry eye syndrome. A specific strategy for increasing the ocular levels of MUC5AC is not yet available. Using a plasmid specially designed to encode human MUC5AC, we evaluated the ability of hybrid cationized gelatin nanoparticles (NPs) containing polyanions (chondroitin sulfate or dextran sulfate) to transfect ocular epithelial cells. NPs were developed using the ionic gelation technique and characterized by a small size (<200 nm), positive zeta potential (+20/+30 mV), and high plasmid association efficiency (>95%). MUC5AC mRNA and protein were detected in conjunctival cells after in vitro transfection of the NPs. The in vivo administration of the NPs resulted in significantly higher MUC5AC expression in the conjunctiva compared to untreated control and naked plasmid. These results provide a proof-of-concept that these NPs are effective vehicles for gene therapy and candidates for restoring the MUC5AC concentration in the ocular surface.

  16. Heterogeneity and persistence length in human ocular mucins.

    PubMed Central

    Round, A N; Berry, M; McMaster, T J; Stoll, S; Gowers, D; Corfield, A P; Miles, M J

    2002-01-01

    Atomic force microscopy (AFM) has been used to investigate the heterogeneity and flexibility of human ocular mucins and their subunits. We have paid particular attention, in terms of theory and experiment, to the problem of inducing the polymers to assume equilibrium conformations at a surface. Mucins deposited from a buffer containing Ni(2+) ions adopt extended conformations on mica akin to those observed for DNA under similar conditions. The heterogeneity of the intracellular native mucins is evident from a histogram of contour lengths, reflecting, in part, the diversity of mucin gene products expressed. Reduction of the native mucin with dithiothreitol, thereby breaking the S==S bonds between cysteine residues, causes a marked reduction in polymer length. These results reflect the modes of transport and assembly of newly synthesized mucins in vivo. By modifying the worm-like chain model for applicability to two dimensions, we have confirmed that under the conditions employed mucin adsorbs to mica in an equilibrated conformation. The determined persistence length of the native mucin, 36 nm, is consistent with that of an extended, flexible polymer; such characteristics will influence the properties of the gels formed in vivo. PMID:12202389

  17. Toll-like receptor activation modulates antimicrobial peptide expression by ocular surface cells.

    PubMed

    Redfern, Rachel L; Reins, Rose Y; McDermott, Alison M

    2011-03-01

    The ability of the ocular surface to respond to pathogens is in part attributed to toll-like receptors (TLRs) that recognize conserved motifs on various microbes. This study examines TLR expression on various ocular surface cells, if TLR agonists can modulate the expression of antimicrobial peptides (AMPs), human beta defensins (hBD) and cathelicidin (hCAP-18/LL-37) which maybe functionally active against Pseudomonas aeruginosa (PA) and if TLR agonists or AMPs can modulate TLR mRNA expression. TLR1-10 mRNA expression was examined in corneal epithelial, corneal stromal cells and conjunctival epithelial cells by RT-PCR. To confirm protein expression flow cytometry or immunostaining was performed for selected TLRs on some cell cultures. Ocular surface cells were cultured with a range of TLR agonists and then hBD-1, 2, 3, or hCAP-18 mRNA and protein expression was determined by RT-PCR and immunoblotting. In some experiments, cells were cultured with a cocktail of agonists for TLR3, 5 and 6/2 and the antimicrobial activity of the culture media was tested against PA. TLR mRNA expression was also examined in primary human corneal epithelial cells (HCEC) treated with either 3 μg/ml of hBD-2, 5 μg/ml of LL-37 or TLR4, 5 and 9 agonists. Overall, the ocular surface cells expressed mRNA for most of the TLRs but some differences were found. TLR2 was not detected in corneal fibroblasts, TLR4 was not detected in primary cultured or freshly isolated HCEC, TLR5 was not detected in conjunctival epithelial cells (IOBA-NHC) and corneal fibroblasts, TLR7 was not detected in freshly isolated HCEC and TLR10 was not detected in HCEC and IOBA-NHC. TLR8 mRNA was not expressed by any of the samples tested. Immunostaining of cadaver corneas revealed TLR5 and 9 expression throughout the cornea while TLR3 was significantly expressed only in the epithelium. Flow cytometry and immunostaining revealed cultured fibroblasts expressed TLR9 but had no significant TLR3 expression. hBD-2 expression

  18. [Retrospective study of ocular complications in patients with human immunodeficiency virus infection before and after HAART].

    PubMed

    Hamamotoo, Ayumi; Tatebayashi, Misako; Uehira, Asako; Kuroda, Sato; Morimoto, Yuko; Nakagawa, Tomoya; Usui, Shinichi; Watanabe, Masaki; Kazuo, Kumiko; Otori, Yasumasa

    2012-08-01

    To describe ocular complications in patients with human immunodeficiency virus (HIV) infection before and after highly active antiretroviral therapy(HAART). We retrospectively reviewed the medical records of 261 patients who underwent HAART and visited our clinic between April, 2007 and March, 2010, and recorded ocular complications, CD4 cell counts, visual acuity and other relevant patient information. Befor HAART patients were found to have the following conditions: HIV retinopathy (41 cases), cytomegalovirus (CMV) retinitis (23 cases), and others (6 cases); and after HAART HIV retinopathy (5 cases), CMV retinitis (16 cases), Immune recovery uveitis(IRU) (4 cases), and others(9 cases). The average CD4+ T-cell counts at diagnosis of CMV retinitis were 45.2/microl before and 116.7/microl after HAART. Since a substantial number of patients develop CMV retinitis after the initiation of HAART, we need to examine patients to check for either the onset or reactivation of CMV retinitis and IRU even after HAART.

  19. The zebrafish eye-a paradigm for investigating human ocular genetics.

    PubMed

    Richardson, R; Tracey-White, D; Webster, A; Moosajee, M

    2017-01-01

    Although human epidemiological and genetic studies are essential to elucidate the aetiology of normal and aberrant ocular development, animal models have provided us with an understanding of the pathogenesis of multiple developmental ocular malformations. Zebrafish eye development displays in depth molecular complexity and stringent spatiotemporal regulation that incorporates developmental contributions of the surface ectoderm, neuroectoderm and head mesenchyme, similar to that seen in humans. For this reason, and due to its genetic tractability, external fertilisation, and early optical clarity, the zebrafish has become an invaluable vertebrate system to investigate human ocular development and disease. Recently, zebrafish have been at the leading edge of preclinical therapy development, with their amenability to genetic manipulation facilitating the generation of robust ocular disease models required for large-scale genetic and drug screening programmes. This review presents an overview of human and zebrafish ocular development, genetic methodologies employed for zebrafish mutagenesis, relevant models of ocular disease, and finally therapeutic approaches, which may have translational leads in the future.

  20. Potential Role of Induced Pluripotent Stem Cells (IPSCs) for Cell-Based Therapy of the Ocular Surface

    PubMed Central

    Casaroli-Marano, Ricardo P.; Nieto-Nicolau, Núria; Martínez-Conesa, Eva M.; Edel, Michael; Álvarez-Palomo, Ana B.

    2015-01-01

    The integrity and normal function of the corneal epithelium are crucial for maintaining the cornea’s transparency and vision. The existence of a cell population with progenitor characteristics in the limbus maintains a dynamic of constant epithelial repair and renewal. Currently, cell-based therapies for bio replacement—cultured limbal epithelial transplantation (CLET) and cultured oral mucosal epithelial transplantation (COMET)—present very encouraging clinical results for treating limbal stem cell deficiency (LSCD) and restoring vision. Another emerging therapeutic approach consists of obtaining and implementing human progenitor cells of different origins in association with tissue engineering methods. The development of cell-based therapies using stem cells, such as human adult mesenchymal or induced pluripotent stem cells (IPSCs), represent a significant breakthrough in the treatment of certain eye diseases, offering a more rational, less invasive, and better physiological treatment option in regenerative medicine for the ocular surface. This review will focus on the main concepts of cell-based therapies for the ocular surface and the future use of IPSCs to treat LSCD. PMID:26239129

  1. Topographical Control of Ocular Cell Types for Tissue Engineering

    PubMed Central

    McHugh, Kevin J.; Saint-Geniez, Magali; Tao, Sarah L.

    2014-01-01

    Visual impairment affects over 285 million people worldwide and has a major impact on an individual’s quality of life. Tissue engineering has the potential to increase quality of life for many of these patients by preventing vision loss or restoring vision using cell-based therapies. However, these strategies will require an understanding of the microenvironmental factors that influence cell behavior. The eye is a well-organized organ whose structural complexity is essential for proper function. Interactions between ocular cells and their highly ordered extracellular matrix are necessary for maintaining key tissue properties including corneal transparency and retinal lamination. Therefore, it is not surprising that culturing these cells in vitro on traditional flat substrates result in irregular morphology. Instead, topographically patterned biomaterials better mimic native extracellular matrix and have been shown to elicit in vivo-like morphology and gene expression which is essential for tissue engineering. Herein we review multiple methods for producing well-controlled topography and discuss optimal biomaterial scaffold design for cells of the cornea, retina, and lens. PMID:23744715

  2. Topographical control of ocular cell types for tissue engineering.

    PubMed

    McHugh, Kevin J; Saint-Geniez, Magali; Tao, Sarah L

    2013-11-01

    Visual impairment affects over 285 million people worldwide and has a major impact on an individual's quality of life. Tissue engineering has the potential to increase the quality of life for many of these patients by preventing vision loss or restoring vision using cell-based therapies. However, these strategies will require an understanding of the microenvironmental factors that influence cell behavior. The eye is a well-organized organ whose structural complexity is essential for proper function. Interactions between ocular cells and their highly ordered extracellular matrix are necessary for maintaining key tissue properties including corneal transparency and retinal lamination. Therefore, it is not surprising that culturing these cells in vitro on traditional flat substrates result in irregular morphology. Instead, topographically patterned biomaterials better mimic native extracellular matrix and have been shown to elicit in vivo-like morphology and gene expression which is essential for tissue engineering. Herein we review multiple methods for producing well-controlled topography and discuss optimal biomaterial scaffold design for cells of the cornea, retina, and lens. Copyright © 2013 Wiley Periodicals, Inc.

  3. Ocular circulatory responses to exhaustive exercise in humans.

    PubMed

    Ikemura, Tsukasa; Hayashi, Naoyuki

    2012-09-01

    It is unclear whether exhaustive dynamic exercise increases ocular blood flow, although we have reported that submaximal exercise increases ocular blood flow. We hypothesized that ocular blood flow decreases at exhaustion, since exhaustion causes hyperventilation, which induces a reduction in PaCO(2). To test this hypothesis, ocular blood flow, blood pressure, and respiratory measurements were made in 12 healthy male subjects during cycle ergometer exercise at 75% of maximal heart rate, until exhaustion. Blood flows in the retinal and choroidal vasculature (RCV), the superior temporal retinal arteriole (STRA), and the superior nasal retinal arteriole (SNRA) were measured with the aid of laser-speckle flowgraphy every 3 min during the exercise. The conductance index (CI) in the ocular vasculature was calculated by dividing the blood flow by the mean arterial pressure (MAP). The mean arterial partial pressure of CO(2) (PaCO(2)) was estimated from tidal volume and end-tidal CO(2) partial pressure. MAP significantly increased from the resting baseline throughout the exercise, while PaCO(2) was significantly decreased at exhaustion and during the recovery period. By 6 min after the onset of exercise, blood flow velocity in the RCV significantly increased by 32 ± 6% (mean ± SD) from the resting baseline value. At exhaustion, blood flow velocity in the RCV did not differ significantly from the resting baseline value, and the STRA blood flow was significantly decreased by 13 ± 4%. The CIs in the RCV, STRA, and SNRA were significantly decreased compared to baseline at exhaustion. These findings suggest that ocular blood flow is increased by submaximal exercise, whereas it is suppressed by the hypocapnia associated with exhaustion.

  4. Isolation and characterization of the 5'-flanking sequence of the human ocular lens MIP gene.

    PubMed

    Wang, X Y; Ohtaka-Maruyama, C; Pisano, M M; Jaworski, C J; Chepelinsky, A B

    1995-12-29

    The MIP (major intrinsic protein) gene, a member of an ancient family of membrane channel genes, encodes the predominant fiber cell membrane protein of the ocular lens. Its specific expression in the lens fibers is temporally and spatially regulated during development. To study the regulation of expression of MIP and delineate the regulatory elements underlying its tissue specificity and ontogenic profile, we have cloned 2840 bp of the human MIP 5'-flanking sequence. The human MIP 5'-flanking sequence contains three complete Alu repetitive elements in tandem at position between nt -1699 and -2684 (nt -1699/-2684). These Alu elements appear to have had a complex evolutionary history with insertions at different times. We have fused DNA fragments containing MIP 5'-flanking sequences to the bacterial cat reporter gene encoding chloramphenicol acetyltransferase and assayed them in primary cultures of chicken lens cells. We have mapped two negative regulatory regions in the human MIP 5'-flanking sequences -1564/-1696 and -948/-1000. We demonstrated that the human MIP 5'-flanking sequence -253/+42 contains a functional promoter in lens cells but is inactive in kidney epithelial cells or mouse fibroblasts, suggesting that this sequence contains regulatory elements responsible for the lens-specific expression of MIP.

  5. Hyaluronan cable formation by ocular trabecular meshwork cells.

    PubMed

    Sun, Ying Ying; Keller, Kate E

    2015-10-01

    Hyaluronan (HA) in the ocular trabecular meshwork (TM) is a critical modulator of aqueous humor outflow. Individual HA strands in the pericellular matrix can coalesce to form cable-like structures, which have different functional properties. Here, we investigated HA structural configuration by TM cells in response to various stimuli known to stimulate extracellular matrix (ECM) remodeling. In addition, the effects of HA cable induction on aqueous outflow resistance was determined. Primary TM cell cultures grown on tissue culture-treated plastic were treated for 12-48 h with TNFα, IL-1α, or TGFβ2. TM cells grown on silicone membranes were subject to mechanical stretch, which induces synthesis and activation of ECM proteolytic enzymes. HA structural configuration was investigated by HA binding protein (HAbp) staining and confocal microscopy. HAbp-labeled cables were induced by TNFα, TGFβ2 and mechanical stretch, but not by IL-1α. HA synthase (HAS) gene expression was quantitated by quantitative RT-PCR and HA concentration was measured by ELISA assay. By quantitative RT-PCR, HAS-1, -2, and -3 genes were differentially up-regulated and showed temporal differences in response to each treatment. HA concentration was increased in the media by TNFα, TGFβ2 and IL-1α, but mechanical stretch decreased pericellular HA concentrations. Immunofluorescence and Western immunoblotting were used to investigate the distribution and protein levels of the HA-binding proteins, tumor necrosis factor-stimulated gene-6 (TSG-6) and inter-α-inhibitor (IαI). Western immunoblotting showed that TSG-6 and IαI were increased by TNFα, TGFβ2 and IL-1α, but mechanical stretch reduced their levels. The underlying substrate appears to affect the identity of IαI·TSG-6·HA complexes since different complexes were detected when TM cells were grown on a silicone substrate compared to a rigid plastic surface. Porcine anterior segments were perfused with 10 μg/ml polyinosinic

  6. Differential effect of rebamipide on transmembrane mucin biosynthesis in stratified ocular surface epithelial cells.

    PubMed

    Uchino, Yuichi; Woodward, Ashley M; Argüeso, Pablo

    2016-12-01

    Mucins are a group of highly glycosylated glycoproteins responsible for the protection of wet-surfaced epithelia. Recent data indicate that transmembrane mucins differ in their contribution to the protective function of the ocular surface, with MUC16 being the most effective barrier on the apical surface glycocalyx. Here, we investigated the role of the mucoprotective drug rebamipide in the regulation of transmembrane mucin biosynthesis using stratified cultures of human corneal and conjunctival epithelial cells. We find that the addition of rebamipide to corneal, but not conjunctival, epithelial cells increased MUC16 protein biosynthesis. Rebamipide did not affect the levels of MUC1, 4 and 20 compared to control. In these experiments, rebamipide had no effect on the expression levels of Notch intracellular domains, suggesting that the rebamipide-induced increase in MUC16 biosynthesis in differentiated corneal cultures is not regulated by Notch signaling. Overall these findings indicate that rebamipide induces the differential upregulation of MUC16 in stratified cultures of human corneal epithelial cells, which may have implications to the proper restoration of barrier function in ocular surface disease. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Development of an Anatomically Accurate Finite Element Human Ocular Globe Model for Blast-Related Fluid-Structure Interaction Studies

    DTIC Science & Technology

    2017-02-01

    ARL-TR-7945 ● FEB 2017 US Army Research Laboratory Development of an Anatomically Accurate Finite Element Human Ocular Globe...ARL-TR-7945 ● FEB 2017 US Army Research Laboratory Development of an Anatomically Accurate Finite Element Human Ocular Globe Model...Finite Element Human Ocular Globe Model for Blast-Related Fluid-Structure Interaction Studies 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM

  8. Unilateral adaptation of the human angular vestibulo-ocular reflex.

    PubMed

    Migliaccio, Americo A; Schubert, Michael C

    2013-02-01

    A recent study showed that the angular vestibulo-ocular reflex (VOR) can be better adaptively increased using an incremental retinal image velocity error signal compared with a conventional constant large velocity-gain demand (×2). This finding has important implications for vestibular rehabilitation that seeks to improve the VOR response after injury. However, a large portion of vestibular patients have unilateral vestibular hypofunction, and training that raises their VOR response during rotations to both the ipsilesional and contralesional side is not usually ideal. We sought to determine if the vestibular response to one side could selectively be increased without affecting the contralateral response. We tested nine subjects with normal vestibular function. Using the scleral search coil and head impulse techniques, we measured the active and passive VOR gain (eye velocity / head velocity) before and after unilateral incremental VOR adaptation training, consisting of self-generated (active) head impulses, which lasted ≈ 15 min. The head impulses consisted of rapid, horizontal head rotations with peak-amplitude 15°, peak-velocity 150°/s and peak-acceleration 3,000°/s(2). The VOR gain towards the adapting side increased after training from 0.92 ± 0.18 to 1.11 ± 0.22 (+22.7 ± 20.2 %) during active head impulses and from 0.91 ± 0.15 to 1.01 ± 0.17 (+11.3 ± 7.5 %) during passive head impulses. During active impulses, the VOR gain towards the non-adapting side also increased by ≈ 8 %, though this increase was ≈ 70 % less than to the adapting side. A similar increase did not occur during passive impulses. This study shows that unilateral vestibular adaptation is possible in humans with a normal VOR; unilateral incremental VOR adaptation may have a role in vestibular rehabilitation. The increase in passive VOR gain after active head impulse adaptation suggests that the training effect is robust.

  9. Ocular involvement of multicentric malignant B-cell lymphoma in a ewe. A case report.

    PubMed

    Rushton, James O; Thaller, Denise; Krametter-Froetscher, Reinhild

    2017-02-16

    An 8.5-year-old, 98 kg female mountain sheep presented with bilateral exophthalmos with reduced retropulsion of the globes, impairing physiologic eyelid closure, sanguineous ocular discharge, as well as swelling of the eyelids and periocular skin. Bilateral vitreal hemorrhage hindering examination of the fundus was further noticed. Systemic signs included reduced general demeanour, presence of a firm mass in the left half of the mammary gland, multiple masses in the area of the vulva and a mass between the shoulder blades. Complete diagnostic work-up, i.  e. complete blood count, blood chemistry and coagulation status, fine needle aspiration of periocular swellings and incisional biopsy of the vulvar masses revealed a diagnosis of malignant B-cell lymphoma. Due to the deterioration in general demeanour and rapid progression of exophthalmos, resulting in bilateral corneal ulceration, despite symptomatic medical treatment, the ewe was humanely euthanized. Gross necropsy and histopathology of select tissue samples confirmed the diagnosis of multicentric malignant B-cell lymphoma. To the authors' knowledge, this is the first report of multicentric malignant B-cell lymphoma involving the ocular adnexa in sheep.

  10. Onset of Ocular Graft-versus-Host Disease Symptoms after Allogeneic Hematopoietic Stem Cell Transplantation

    PubMed Central

    Shikari, Hasanain; Amparo, Francisco; Saboo, Ujwala; Dana, Reza

    2014-01-01

    Objective To study the factors affecting the time to onset of ocular GVHD in patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT). Methods A retrospective chart review of 200 patients with ocular GVHD was performed to evaluate the association between various donor-recipient characteristics on the time to onset of ocular GVHD after allo-HSCT. Results The median time to onset of chronic ocular GVHD after allo-HSCT was 293 days (range 26 to 2308). Patients receiving fully HLA-matched transplants had a delayed onset of ocular GVHD (median 294 days) compared to mismatched transplants (219 days; P=0.029). HLA-matched transplants from related donors had delayed onset of ocular GVHD (307 days) compared to HLA-matched (286 days; P=0.168) and HLA-mismatched (231 days; P=0.015) transplants from unrelated donors. Ocular GVHD followed systemic GVHD in 76% of patients but preceded systemic disease in 7%, occurred concurrently in 15%, and was not associated with systemic GVHD in 2% of patients. The time elapsed between the occurrence of systemic and ocular GVHD was significantly longer in matched-related transplants (250 days) than in matched-unrelated transplants (120 days; P=0.004). Conclusion The onset of ocular GVHD after allogeneic hematopoietic stem cell transplantation is variable and is influenced by the donor-recipient matching characteristics. In the majority of patients with GVHD ocular involvement follows the occurrence of systemic manifestations; however, importantly, it can also precede or develop independently of systemic disease in a minority. Regular ophthalmic follow-up is recommended after allo-HSCT regardless the concurrent systemic GVHD status. PMID:25603230

  11. Therapeutic Immunization with a Mixture of Herpes Simplex Virus 1 Glycoprotein D-Derived “Asymptomatic” Human CD8+ T-Cell Epitopes Decreases Spontaneous Ocular Shedding in Latently Infected HLA Transgenic Rabbits: Association with Low Frequency of Local PD-1+ TIM-3+ CD8+ Exhausted T Cells

    PubMed Central

    Khan, Arif A.; Srivastava, Ruchi; Chentoufi, Aziz A.; Geertsema, Roger; Thai, Nhi Thi Uyen; Dasgupta, Gargi; Osorio, Nelson; Kalantari, Mina; Nesburn, Anthony B.; Wechsler, Steven L.

    2015-01-01

    ABSTRACT Most blinding ocular herpetic disease is due to reactivation of herpes simplex virus 1 (HSV-1) from latency rather than to primary acute infection. No herpes simplex vaccine is currently available for use in humans. In this study, we used the HLA-A*02:01 transgenic (HLA Tg) rabbit model of ocular herpes to assess the efficacy of a therapeutic vaccine based on HSV-1 gD epitopes that are recognized mainly by CD8+ T cells from “naturally” protected HLA-A*02:01-positive, HSV-1-seropositive healthy asymptomatic (ASYMP) individuals (who have never had clinical herpes disease). Three ASYMP CD8+ T-cell epitopes (gD53–61, gD70–78, and gD278–286) were linked with a promiscuous CD4+ T-cell epitope (gD287–317) to create 3 separate pairs of CD4-CD8 peptides, which were then each covalently coupled to an Nε-palmitoyl-lysine moiety, a Toll-like receptor 2 (TLR-2) ligand. This resulted in the construction of 3 CD4-CD8 lipopeptide vaccines. Latently infected HLA Tg rabbits were immunized with a mixture of these 3 ASYMP lipopeptide vaccines, delivered as eye drops in sterile phosphate-buffered saline (PBS). The ASYMP therapeutic vaccination (i) induced HSV-specific CD8+ T cells that prevent HSV-1 reactivation ex vivo from latently infected explanted trigeminal ganglia (TG), (ii) significantly reduced HSV-1 shedding detected in tears, (iii) boosted the number and function of HSV-1 gD epitope-specific CD8+ T cells in draining lymph nodes (DLN), conjunctiva, and TG, and (iv) was associated with fewer exhausted HSV-1 gD-specific PD-1+ TIM-3+ CD8+ T cells. The results underscore the potential of an ASYMP CD8+ T-cell epitope-based therapeutic vaccine strategy against recurrent ocular herpes. IMPORTANCE Seventy percent to 90% of adults harbor herpes simplex virus 1 (HSV-1), which establishes lifelong latency in sensory neurons of the trigeminal ganglia. This latent state sporadically switches to spontaneous reactivation, resulting in viral shedding in tears. Most

  12. Therapeutic immunization with a mixture of herpes simplex virus 1 glycoprotein D-derived “asymptomatic” human CD8+ T-cell epitopes decreases spontaneous ocular shedding in latently infected HLA transgenic rabbits: association with low frequency of local PD-1+ TIM-3+ CD8+ exhausted T cells.

    PubMed

    Khan, Arif A; Srivastava, Ruchi; Chentoufi, Aziz A; Geertsema, Roger; Thai, Nhi Thi Uyen; Dasgupta, Gargi; Osorio, Nelson; Kalantari, Mina; Nesburn, Anthony B; Wechsler, Steven L; BenMohamed, Lbachir

    2015-07-01

    Most blinding ocular herpetic disease is due to reactivation of herpes simplex virus 1 (HSV-1) from latency rather than to primary acute infection. No herpes simplex vaccine is currently available for use in humans. In this study, we used the HLA-A*02:01 transgenic (HLA Tg) rabbit model of ocular herpes to assess the efficacy of a therapeutic vaccine based on HSV-1 gD epitopes that are recognized mainly by CD8(+) T cells from "naturally" protected HLA-A*02:01-positive, HSV-1-seropositive healthy asymptomatic (ASYMP) individuals (who have never had clinical herpes disease). Three ASYMP CD8(+) T-cell epitopes (gD(53-61), gD(70-78), and gD(278-286)) were linked with a promiscuous CD4(+) T-cell epitope (gD(287-317)) to create 3 separate pairs of CD4-CD8 peptides, which were then each covalently coupled to an Nε-palmitoyl-lysine moiety, a Toll-like receptor 2 (TLR-2) ligand. This resulted in the construction of 3 CD4-CD8 lipopeptide vaccines. Latently infected HLA Tg rabbits were immunized with a mixture of these 3 ASYMP lipopeptide vaccines, delivered as eye drops in sterile phosphate-buffered saline (PBS). The ASYMP therapeutic vaccination (i) induced HSV-specific CD8(+) T cells that prevent HSV-1 reactivation ex vivo from latently infected explanted trigeminal ganglia (TG), (ii) significantly reduced HSV-1 shedding detected in tears, (iii) boosted the number and function of HSV-1 gD epitope-specific CD8(+) T cells in draining lymph nodes (DLN), conjunctiva, and TG, and (iv) was associated with fewer exhausted HSV-1 gD-specific PD-1(+) TIM-3+ CD8(+) T cells. The results underscore the potential of an ASYMP CD8(+) T-cell epitope-based therapeutic vaccine strategy against recurrent ocular herpes. Seventy percent to 90% of adults harbor herpes simplex virus 1 (HSV-1), which establishes lifelong latency in sensory neurons of the trigeminal ganglia. This latent state sporadically switches to spontaneous reactivation, resulting in viral shedding in tears. Most blinding

  13. An engineered human conjunctival-like tissue to study ocular surface inflammatory diseases.

    PubMed

    García-Posadas, Laura; Soriano-Romaní, Laura; López-García, Antonio; Diebold, Yolanda

    2017-01-01

    The aim of this study was to develop a three-dimensional model of the human conjunctiva that can be used to perform physiology and pathophysiology experiments. Fibrin-based matrices (derived from human plasma or plasma cryoprecipitate) were used as scaffolds, and primary cells were obtained from conjunctival tissue. Conjunctival constructs were analyzed by immunofluorescent staining and scanning electron microscopy and cell proliferation was measured with alamarBlue® assay. After characterizing the constructs, four different experimental conditions were analyzed in cryoprecipitate matrices: controls, air-lifted cultures (to increase cell stratification), partially desiccated cultures (to mimic dry eye disease), and IL-13-treated cultures (to mimic allergy). Constructs were stained with hematoxylin/eosin to observe changes in morphology. High molecular weight glycoconjugates were identified by HPA staining. MUC5AC and IL-6 secretion was evaluated by ELISA. The fibrin-based matrices supported conjunctival cell growth. Epithelial cells grew on the surface of the scaffolds and underwent stratification that increased over time. These cells had microvilli, which suggests cell polarization and functionality. Fibroblasts were integrated in the scaffold and showed elongated shape. Compared to controls, air-lifted construct had increased epithelial stratification and upregulated MUC5AC secretion. Increased MUC5AC secretion also occurred in partially desiccated and IL-13-treated cultures. The inflammatory status of cells was evaluated by IL-6 levels which were increased in air-lifted and partially desiccated cultures, but not in IL-13-treated ones. In conclusion, we have developed a new three-dimensional model of human conjunctiva that can be used to study ocular surface inflammatory diseases.

  14. An engineered human conjunctival-like tissue to study ocular surface inflammatory diseases

    PubMed Central

    García-Posadas, Laura; Soriano-Romaní, Laura; López-García, Antonio; Diebold, Yolanda

    2017-01-01

    The aim of this study was to develop a three-dimensional model of the human conjunctiva that can be used to perform physiology and pathophysiology experiments. Fibrin-based matrices (derived from human plasma or plasma cryoprecipitate) were used as scaffolds, and primary cells were obtained from conjunctival tissue. Conjunctival constructs were analyzed by immunofluorescent staining and scanning electron microscopy and cell proliferation was measured with alamarBlue® assay. After characterizing the constructs, four different experimental conditions were analyzed in cryoprecipitate matrices: controls, air-lifted cultures (to increase cell stratification), partially desiccated cultures (to mimic dry eye disease), and IL-13-treated cultures (to mimic allergy). Constructs were stained with hematoxylin/eosin to observe changes in morphology. High molecular weight glycoconjugates were identified by HPA staining. MUC5AC and IL-6 secretion was evaluated by ELISA. The fibrin-based matrices supported conjunctival cell growth. Epithelial cells grew on the surface of the scaffolds and underwent stratification that increased over time. These cells had microvilli, which suggests cell polarization and functionality. Fibroblasts were integrated in the scaffold and showed elongated shape. Compared to controls, air-lifted construct had increased epithelial stratification and upregulated MUC5AC secretion. Increased MUC5AC secretion also occurred in partially desiccated and IL-13-treated cultures. The inflammatory status of cells was evaluated by IL-6 levels which were increased in air-lifted and partially desiccated cultures, but not in IL-13-treated ones. In conclusion, we have developed a new three-dimensional model of human conjunctiva that can be used to study ocular surface inflammatory diseases. PMID:28248962

  15. In vitro biocompatibility of degradable biopolymers in cell line cultures from various ocular tissues: direct contact studies.

    PubMed

    Huhtala, A; Pohjonen, T; Salminen, L; Salminen, A; Kaarniranta, K; Uusitalo, H

    2007-11-01

    Synthetic biodegradable polymers have many potential therapeutic applications. In ophthalmology, biodegradable polymers have been used as viscoelastic agents and surgical implants. Other potential applications include controlled release of drugs and growth factors, gene therapy, and tissue engineering. In the present study, in vitro biocompatibility of three biodegradable polymers, 50:50 PDLGA, 85:15 PDLGA, and Inion GTR membrane was evaluated in comparison to tissue culture polystyrene by investigating cell proliferation and potential acute toxicity by the WST-1 cytotoxicity/cell proliferation test, the ATP test, and the lactate dehydrogenase (LDH) test. Evaluations were conducted with cell line cultures from various ocular tissues, human corneal epithelial cells (HCE), rabbit stromal fibroblasts (SIRC), bovine corneal endothelial cells (BCE), human conjunctival epithelial cells (IOBA-NHC), and human retinal pigment epithelial cells (ARPE-19) by direct contact studies by plating the cells on the polymer film specimens in 96-wells. The proliferation results show that cell lines from various ocular tissues attached and grew on PDLGA 50:50, PDLGA 85:15, and Inion GTR membrane. Cytotoxicity experiments with the LDH and ATP tests showed no or extremely slight toxic adverse effects. These polymers have potential to be used as scaffolds in cell transplantation devices or as surgical implants. Copyright (c) 2007 Wiley Periodicals, Inc.

  16. Antiangiogenic immunotherapy targeting Flk-1, DNA vaccine and adoptive T cell transfer, inhibits ocular neovascularization

    SciTech Connect

    Zhang, Han; Sonoda, Koh-Hei; Hijioka, Kuniaki; Qiao, Hong; Oshima, Yuji; Ishibashi, Tatsuro

    2009-04-17

    Ocular neovascularization (NV) is the primary cause of blindness in a wide range of ocular diseases. The exact mechanism underlying the pathogenesis of ocular NV is not yet well understood, and so there is no satisfactory therapy for ocular NV. Here, we describe a strategy targeting Flk-1, a self-antigen overexpressed on proliferating endothelial cells in ocular NV, by antiangiogenic immunotherapy-DNA vaccine and adoptive T cell therapy. An oral DNA vaccine encoding Flk-1 carried by attenuated Salmonella typhimurium markedly suppressed development of laser-induced choroidal NV. We further demonstrated that adoptive transfer of vaccine-induced CD8{sup +} T cells reduced pathological preretinal NV, with a concomitant facilitation of physiological revascularization after oxygen-induced retinal vessel obliteration. However, physiological retinal vascular development was unaffected in neonatal mice transferred with vaccine-induced CD8{sup +} T cells. These findings suggested that antiangiogenic immunotherapy targeting Flk-1 such as vaccination and adoptive immunotherapy may contribute to future therapies for ocular NV.

  17. The human ocular torsion position response during yaw angular acceleration.

    PubMed

    Smith, S T; Curthoys, I S; Moore, S T

    1995-07-01

    Recent results by Wearne [(1993) Ph.D. thesis] using the scleral search-coil method of measuring eye position indicate that changes in ocular torsion position (OTP) occur during yaw angular acceleration about an earth vertical axis. The present set of experiments, using an image processing method of eye movement measurement free from the possible confound of search coil slippage, demonstrates the generality and repeatability of this phenomenon and examines its possible causes. The change in torsion position is not a linear vestibulo-ocular reflex (LVOR) response to interaural linear acceleration stimulation of the otoliths, but rather the effect is dependent on the characteristics of the angular acceleration stimulus, commencing at the onset and decaying at the offset of the angular acceleration. In the experiments reported here, the magnitude of the angular acceleration stimulus was varied and the torsion position response showed corresponding variations. We consider that the change in torsion position observed during angular acceleration is most likely to be due to activity of the semicircular canals.

  18. Sustained Ocular Hypertension Induces Dendritic Degeneration of Mouse Retinal Ganglion Cells That Depends on Cell Type and Location

    PubMed Central

    Feng, Liang; Zhao, Yan; Yoshida, Miho; Chen, Hui; Yang, Jessica F.; Kim, Ted S.; Cang, Jianhua; Troy, John B.; Liu, Xiaorong

    2013-01-01

    Purpose. Glaucoma is characterized by retinal ganglion cell (RGC) death and frequently associated with elevated IOP. How RGCs degenerate before death is little understood, so we sought to investigate RGC degeneration in a mouse model of ocular hypertension. Methods. A laser-induced mouse model of chronic ocular hypertension mimicked human high-tension glaucoma. Immunohistochemistry was used to characterize overall RGC loss and an optomotor behavioral test to measure corresponding changes in visual capacity. Changes in RGC functional properties were characterized by a large-scale multielectrode array (MEA). The transgenic Thy-1-YFP mouse line, in which a small number of RGCs are labeled with yellow fluorescent protein (YFP), permitted investigation of whether subtypes of RGCs or RGCs from particular retinal areas were differentially vulnerable to elevated IOP. Results. Sustained IOP elevation in mice was achieved by laser photocoagulation. We confirmed RGC loss and decreased visual acuity in ocular hypertensive mice. Furthermore, these mice had fewer visually responsive cells with smaller receptive field sizes compared to controls. We demonstrated that RGC dendritic shrinkage started from the vertical axis of hypertensive eyes and that mono-laminated ON cells were more susceptible to IOP elevation than bi-laminated ON-OFF cells. Moreover, a subgroup of ON RGCs labeled by the SMI-32 antibody exhibited significant dendritic atrophy in the superior quadrant of the hypertensive eyes. Conclusions. RGC degeneration depends on subtype and location in hypertensive eyes. This study introduces a valuable model to investigate how the structural and functional degeneration of RGCs leads to visual impairments. PMID:23322576

  19. Stem Cell Therapy for Treatment of Ocular Disorders.

    PubMed

    Sivan, Padma Priya; Syed, Sakinah; Mok, Pooi-Ling; Higuchi, Akon; Murugan, Kadarkarai; Alarfaj, Abdullah A; Munusamy, Murugan A; Awang Hamat, Rukman; Umezawa, Akihiro; Kumar, Suresh

    2016-01-01

    Sustenance of visual function is the ultimate focus of ophthalmologists. Failure of complete recovery of visual function and complications that follow conventional treatments have shifted search to a new form of therapy using stem cells. Stem cell progenitors play a major role in replenishing degenerated cells despite being present in low quantity and quiescence in our body. Unlike other tissues and cells, regeneration of new optic cells responsible for visual function is rarely observed. Understanding the transcription factors and genes responsible for optic cells development will assist scientists in formulating a strategy to activate and direct stem cells renewal and differentiation. We review the processes of human eye development and address the strategies that have been exploited in an effort to regain visual function in the preclinical and clinical state. The update of clinical findings of patients receiving stem cell treatment is also presented.

  20. Stem Cell Therapy for Treatment of Ocular Disorders

    PubMed Central

    Sivan, Padma Priya; Syed, Sakinah; Mok, Pooi-Ling; Higuchi, Akon; Murugan, Kadarkarai; Alarfaj, Abdullah A.; Munusamy, Murugan A.; Awang Hamat, Rukman; Umezawa, Akihiro; Kumar, Suresh

    2016-01-01

    Sustenance of visual function is the ultimate focus of ophthalmologists. Failure of complete recovery of visual function and complications that follow conventional treatments have shifted search to a new form of therapy using stem cells. Stem cell progenitors play a major role in replenishing degenerated cells despite being present in low quantity and quiescence in our body. Unlike other tissues and cells, regeneration of new optic cells responsible for visual function is rarely observed. Understanding the transcription factors and genes responsible for optic cells development will assist scientists in formulating a strategy to activate and direct stem cells renewal and differentiation. We review the processes of human eye development and address the strategies that have been exploited in an effort to regain visual function in the preclinical and clinical state. The update of clinical findings of patients receiving stem cell treatment is also presented. PMID:27293447

  1. Towards a defined, serum- and feeder-free culture of stratified human oral mucosal epithelium for ocular surface reconstruction.

    PubMed

    Ilmarinen, Tanja; Laine, Juhana; Juuti-Uusitalo, Kati; Numminen, Jura; Seppänen-Suuronen, Riitta; Uusitalo, Hannu; Skottman, Heli

    2013-12-01

    Ocular surface reconstruction with cultivated oral mucosal epithelial transplantation technique is a viable treatment option for severe ocular surface injuries and diseases with limbal stem cell deficiency. Currently, this technique is based on utilization of xenogenic, allogenic or undefined components such as murine 3T3 feeders, serum and amniotic membrane. In this study, we aimed to find a more defined culture method to generate stratified human oral mucosal epithelium. In this study, we have examined the formation of stratified cell sheets from human oral mucosal epithelial cells under serum-free culture environment both in the absence and presence of fibroblast-conditioned culture medium and elevated epidermal growth factor (EGF) concentration. In all examined culture conditions, the cultivated oral epithelial cells formed a stratified tissue, which was positive for keratins K3/12, K4 and K13. The tissue-engineered oral epithelia also expressed proliferation and progenitor markers Ki67 and p63 in the basal layer of the cell sheets, suggesting that the epithelia still had regenerative capacity. The cultures presented expression of tight junction proteins ZO-1 and occludin and high transepithelial electrical resistance values. In this culture method, we have been able to produce stratified cell sheets successfully without serum, conditioning of the medium or increased EGF concentration. We provide a novel protocol to produce tight multi-layered epithelium with proliferative potential, which can be easily adapted for cultivated oral mucosal epithelial transplantation. © 2012 The Authors. Acta Ophthalmologica © 2012 Acta Ophthalmologica Scandinavica Foundation.

  2. Identification of androgen receptor protein and 5α-reductase mRNA in human ocular tissues

    PubMed Central

    Rocha, E.; Wickham, L; da Silveira, L. A; Krenzer, K.; Yu, F.; Toda, I.; Sullivan, B.; Sullivan, D.

    2000-01-01

    BACKGROUND/AIMS—Androgens have been reported to influence the structural organisation, functional activity, and/or pathological features of many ocular tissues. In addition, these hormones have been proposed as a topical therapy for such conditions as dry eye syndromes, corneal wound healing, and high intraocular pressure. To advance our understanding of androgen action in the eye, the purpose of the present study was twofold: firstly, to determine whether tissues of the anterior and posterior segments contain androgen receptor protein, which might make them susceptible to hormone effects following topical application; and, secondly, to examine whether these tissues contain the mRNA for types 1 and/or 2 5α-reductase, an enzyme that converts testosterone to the very potent metabolite, dihydrotestosterone.
METHODS—Human ocular tissues and cells were obtained and processed for histochemical and molecular biological procedures. Androgen receptor protein was identified by utilising specific immunoperoxidase techniques. The analysis of type 1 and type 2 5α-reductase mRNAs was performed by the use of RT-PCR, agarose gel electrophoresis, and DNA sequence analysis. All immunohistochemical evaluations and PCR amplifications included positive and negative controls.
RESULTS—These findings show that androgen receptor protein exists in the human lacrimal gland, meibomian gland, cornea, bulbar and forniceal conjunctivae, lens epithelial cells, and retinal pigment epithelial cells. In addition, our results demonstrate that the mRNAs for types 1 and 2 5α-reductase occur in the human lacrimal gland, meibomian gland, bulbar conjunctiva, cornea, and RPE cells.
CONCLUSION—These combined results indicate that multiple ocular tissues may be target sites for androgen action.

 PMID:10611104

  3. Human ocular effects from self-reported exposures to Roundup herbicides.

    PubMed

    Acquavella, J F; Weber, J A; Cullen, M R; Cruz, O A; Martens, M A; Holden, L R; Riordan, S; Thompson, M; Farmer, D

    1999-08-01

    We evaluated ocular effects from reported human exposures to Roundup herbicides based on 1513 calls to an American Association of Poison Control Centers (AAPCC) certified regional poison center during the years 1993 through 1997. The preponderance of reported exposures were judged by poison center specialists to result in either no injury (21%) or transient minor symptoms (70%). There was some temporary injury in 2% of cases; one injury took more than 2 weeks to resolve. In no instance did exposure result in permanent change to the structure or function of the eye. Since the representativeness of calls to poison control centers is unknown, several interpretations of these findings are possible. The most conservative interpretation is that there were no serious ocular effects from exposure to Roundup herbicides during a 5 year period among callers to a single regional poison center. A less conservative interpretation would be that severe ocular effects from Roundup exposures are rare among users of these products.

  4. Multifractal nature of ocular aberration dynamics of the human eye

    PubMed Central

    Hampson, Karen M.; Mallen, Edward A. H.

    2011-01-01

    Ocular monochromatic aberrations display dynamic behavior even when the eye is fixating on a stationary stimulus. The fluctuations are commonly characterized in the frequency domain using the power spectrum obtained via the Fourier transform. In this paper we used a wavelet-based multifractal analytical approach to provide a more in depth analysis of the nature of the aberration fluctuations. The aberrations of five subjects were measured at 21 Hz using an open-view Shack-Hartmann sensor. We show that the aberration dynamics are multifractal. The most frequently occurring Hölder exponent for the rms wavefront error, averaged across the five subjects, was 0.31 ± 0.10. This suggests that the time course of the aberration fluctuations is antipersistant. Future applications of multifractal analysis are discussed. PMID:21412452

  5. Innate immunity of the ocular surface.

    PubMed

    Ueta, Mayumi; Kinoshita, Shigeru

    2010-02-15

    The ocular surface epithelium serves a critical function as the defensive front line of the innate immune system. While the detection of microbes is arguably its most important task, an exaggerated host defense reaction to endogenous bacterial flora may initiate and perpetuate inflammatory mucosal responses. The ability of cells to recognize pathogen-associated molecular patterns (PAMPs) mainly depends on the expression of a family of Toll-like receptors (TLRs). A healthy ocular surface is not inflammatory, even though ocular surface epithelium is in constant contact with bacteria and bacterial products. In this study, we show that human ocular surface epithelial cells, both corneal and conjuctival epithelial cells, respond to viral double-stranded RNA mimic polyI:C to produce pro-inflammatory cytokines through TLR3, while they fail to respond functionally to lipopolysaccharide, a TLR4 ligand. Moreover, human ocular surface epithelium responds to flagellins from ocular pathogenic, but not ocular non-pathogenic bacteria, to produce pro-inflammatory cytokines through TLR5. Thus, ocular surface epithelial cells selectively respond to microbial components and induce limited inflammation; immune-competent cells can recognize microbial components through TLRs and induce the inflammation. The unique innate immune response of the ocular surface epithelium may contribute to its coexistence with commensal bacteria. Inflammatory bowel disease is thought to result from an abnormal response to the gut microbiota. Thus, we also considered the possibility of an association between ocular surface inflammation and a disordered innate immune response. IkappaBzeta is important for TLR signaling, in mice, its knock-out produced severe, spontaneous ocular surface inflammation, the eventual loss of goblet cells, and spontaneous perioral inflammation, suggesting that dysfunction/abnormality of innate immunity can lead to ocular surface inflammation. Copyright 2009 Elsevier Inc. All

  6. Human Asymptomatic Epitopes Identified from the Herpes Simplex Virus Tegument Protein VP13/14 (UL47) Preferentially Recall Polyfunctional Effector Memory CD44high CD62Llow CD8+ TEM Cells and Protect Humanized HLA-A*02:01 Transgenic Mice against Ocular Herpesvirus Infection

    PubMed Central

    Srivastava, Ruchi; Khan, Arif A.; Garg, Sumit; Syed, Sabrina A.; Furness, Julie N.; Vahed, Hawa; Pham, Tiffany; Yu, Howard T.; Nesburn, Anthony B.

    2016-01-01

    ABSTRACT Herpes simplex virus 1 (HSV-1) infection is widespread among humans. The HSV-1 virion protein 13/14 (VP13/14), also known as UL47, is a tegument antigen targeted by CD8+ T cells from HSV-seropositive individuals. However, whether VP13/14-specific CD8+ T cells play a role in the natural protection seen in asymptomatic (ASYMP) individuals (individuals who have never had a clinical herpetic disease) has not been elucidated. Using predictive computer-assisted algorithms, we identified 10 potential HLA-A*02:01-restricted CD8+ T-cell epitopes from the 693-amino-acid sequence of the VP13/14 protein. Three out of 10 epitopes exhibited a high to moderate affinity of binding to soluble HLA-A*02:01 molecules. The phenotype and function of CD8+ T cells specific for each epitope were compared in HLA-A*02:01-positive ASYMP individuals and symptomatic (SYMP) individuals (individuals who have frequent clinical herpetic diseases) using determination of a combination of tetramer frequency and the levels of granzyme B, granzyme K, perforin, gamma interferon, tumor necrosis factor alpha, and interleukin-2 production and CD107a/b cytotoxic degranulation. High frequencies of multifunctional CD8+ T cells directed against three epitopes, VP13/14 from amino acids 286 to 294 (VP13/14286–294), VP13/14 from amino acids 504 to 512 (VP13/14504–512), and VP13/14 from amino acids 544 to 552 (VP13/14544–552), were detected in ASYMP individuals, while only low frequencies were detected in SYMP individuals. The three epitopes also predominantly recalled more CD45RAlow CD44high CCR7low CD62Llow CD8+ effector memory T cells (TEM cells) in ASYMP individuals than SYMP individuals. Moreover, immunization of HLA-A*02:01 transgenic mice with the three CD8+ TEM-cell epitopes from ASYMP individuals induced robust and polyfunctional HSV-specific CD8+ TEM cells associated with strong protective immunity against ocular herpesvirus infection and disease. Our findings outline the phenotypic and

  7. Binocular Coordination of the Human Vestibulo-Ocular Reflex during Off-axis Pitch Rotation

    NASA Technical Reports Server (NTRS)

    Wood, S. J.; Reschke, M. F.; Kaufman, G. D.; Black, F. O.; Paloski, W. H.

    2006-01-01

    Head movements in the sagittal pitch plane typically involve off-axis rotation requiring both vertical and horizontal vergence ocular reflexes to compensate for angular and translational motion relative to visual targets of interest. The purpose of this study was to compare passive pitch VOR responses during rotation about an Earth-vertical axis (canal only cues) with off-axis rotation (canal and otolith cues). Methods. Eleven human subjects were oscillated sinusoidally at 0.13, 0.3 and 0.56 Hz while lying left-side down with the interaural axis either aligned with the axis of rotation or offset by 50 cm. In a second set of measurements, twelve subjects were also tested during sinusoidally varying centrifugation over the same frequency range. The modulation of vertical and horizontal vergence ocular responses was measured with a binocular videography system. Results. Off-axis pitch rotation enhanced the vertical VOR at lower frequencies and enhanced the vergence VOR at higher frequencies. During sinusoidally varying centrifugation, the opposite trend was observed for vergence, with both vertical and vergence vestibulo-ocular reflexes being suppressed at the highest frequency. Discussion. These differential effects of off-axis rotation over the 0.13 to 0.56 Hz range are consistent with the hypothesis that otolith-ocular reflexes are segregated in part on the basis of stimulus frequency. At the lower frequencies, tilt otolith-ocular responses compensate for declining canal input. At higher frequencies, translational otolith-ocular reflexes compensate for declining visual contributions to the kinematic demands required for fixating near targets.

  8. The human vestibulo-ocular reflex during linear locomotion

    NASA Technical Reports Server (NTRS)

    Moore, S. T.; Hirasaki, E.; Raphan, T.; Cohen, B.

    2001-01-01

    During locomotion, there is a translation and compensatory rotation of the head in both the vertical and horizontal planes. During moderate to fast walking (100 m/min), vertical head translation occurs at the frequency of stepping (2 Hz) and generates peak linear acceleration of 0.37 g. Lateral head translation occurs at the stride frequency (1 Hz) and generates peak linear acceleration of 0.1 g. Peak head pitch and yaw angular velocities are approximately 17 degrees/s. The frequency and magnitude of these head movements are within the operational range of both the linear and angular vestibulo-ocular reflex (IVOR and aVOR). Vertical eye movements undergo a phase reversal from near to far targets. When viewing a far (>1 m) target, vertical eye velocity is typical of an aVOR response; that is, it is compensatory for head pitch. At close viewing distances (<1 m), vertical eye velocity is in phase with head pitch and is compensatory for vertical head translation, suggesting that the IVOR predominantly generates the eye movement response. Horizontal head movements during locomotion occur at the stride frequency of 1 Hz, where the IVOR gain is low. Horizontal eye movements are compensatory for head yaw at all viewing distances and are likely generated by the aVOR.

  9. The human vestibulo-ocular reflex during linear locomotion

    NASA Technical Reports Server (NTRS)

    Moore, S. T.; Hirasaki, E.; Raphan, T.; Cohen, B.

    2001-01-01

    During locomotion, there is a translation and compensatory rotation of the head in both the vertical and horizontal planes. During moderate to fast walking (100 m/min), vertical head translation occurs at the frequency of stepping (2 Hz) and generates peak linear acceleration of 0.37 g. Lateral head translation occurs at the stride frequency (1 Hz) and generates peak linear acceleration of 0.1 g. Peak head pitch and yaw angular velocities are approximately 17 degrees/s. The frequency and magnitude of these head movements are within the operational range of both the linear and angular vestibulo-ocular reflex (IVOR and aVOR). Vertical eye movements undergo a phase reversal from near to far targets. When viewing a far (>1 m) target, vertical eye velocity is typical of an aVOR response; that is, it is compensatory for head pitch. At close viewing distances (<1 m), vertical eye velocity is in phase with head pitch and is compensatory for vertical head translation, suggesting that the IVOR predominantly generates the eye movement response. Horizontal head movements during locomotion occur at the stride frequency of 1 Hz, where the IVOR gain is low. Horizontal eye movements are compensatory for head yaw at all viewing distances and are likely generated by the aVOR.

  10. JUN is important for ocular hypertension-induced retinal ganglion cell degeneration.

    PubMed

    Syc-Mazurek, Stephanie B; Fernandes, Kimberly A; Libby, Richard T

    2017-07-20

    Ocular hypertension, a major risk factor for glaucoma, is thought to trigger glaucomatous neurodegeneration through injury to retinal ganglion cell (RGC) axons. The molecular signaling pathway leading from ocular hypertension to RGC degeneration, however, is not well defined. JNK signaling, a component of the mitogen-activated protein kinase (MAPK) family, and its canonical target, the transcription factor JUN, have been shown to regulate neurodegeneration in many different systems. JUN is expressed after glaucoma-relevant injuries and Jun deficiency protects RGCs after mechanical injury to the optic nerve. Here, we tested the importance of JNK-JUN signaling for RGC death after ocular hypertensive axonal injury in an age-related, mouse model of ocular hypertension. Immunohistochemistry was performed to evaluate JUN expression in ocular hypertensive DBA/2J mice. JUN was expressed in a temporal and spatial pattern consistent with a role in glaucomatous injury. To determine the importance of JUN in ocular hypertension-induced RGC death, a floxed allele of Jun and a retinal expressed cre recombinase (Six3-cre) were backcrossed onto the DBA/2J background. Intraocular pressure (IOP) and gross morphology of the retina and optic nerve head were assessed to determine whether removing Jun from the developing retina altered IOP elevation or retinal development. Jun deficiency in the retina did not alter DBA/2J IOP elevation or retinal development. Optic nerves and retinas were assessed at ages known to have glaucomatous damage in DBA/2J mice. Jun deficiency protected RGC somas from ocular hypertensive injury, but did not protect RGC axons from glaucomatous neurodegeneration. Jun is a major regulator of RGC somal degeneration after glaucomatous ocular hypertensive injury. These results suggest in glaucomatous neurodegeneration, JNK-JUN signaling has a major role as a pro-death signaling pathway between axonal injury and somal degeneration.

  11. Role of the Retinal Vascular Endothelial Cell in Ocular Disease

    PubMed Central

    Bharadwaj, Arpita S.; Appukuttan, Binoy; Wilmarth, Phillip A.; Pan, Yuzhen; Stempel, Andrew J.; Chipps, Timothy J.; Benedetti, Eric E.; Zamora, David O.; Choi, Dongseok; David, Larry L.; Smith, Justine R.

    2012-01-01

    Retinal endothelial cells line the arborizing microvasculature that supplies and drains the neural retina. The anatomical and physiological characteristics of these endothelial cells are consistent with nutritional requirements and protection of a tissue critical to vision. On the one hand, the endothelium must ensure the supply of oxygen and other nutrients to the metabolically active retina, and allow access to circulating cells that maintain the vasculature or survey the retina for the presence of potential pathogens. On the other hand, the endothelium contributes to the blood-retinal barrier that protects the retina by excluding circulating molecular toxins, microorganisms, and pro-inflammatory leukocytes. Features required to fulfill these functions may also predispose to disease processes, such as retinal vascular leakage and neovascularization, and trafficking of microbes and inflammatory cells. Thus, the retinal endothelial cell is a key participant in retinal ischemic vasculopathies that include diabetic retinopathy and retinopathy of prematurity, and retinal inflammation or infection, as occurs in posterior uveitis. Using gene expression and proteomic profiling, it has been possible to explore the molecular phenotype of the human retinal endothelial cell and contribute to understanding of the pathogenesis of these diseases. In addition to providing support for the involvement of well-characterized endothelial molecules, profiling has the power to identify new players in retinal pathologies. Findings may have implications for the design of new biological therapies. Additional progress in this field is anticipated as other technologies, including epigenetic profiling methods, whole transcriptome shotgun sequencing, and metabolomics, are used to study the human retinal endothelial cell. PMID:22982179

  12. Ocular Fluid As a Replacement for Serum in Cell Cryopreservation Media

    PubMed Central

    Venna, Naresh Kumar; Murthy, Ch Lakshmi N.; Idris, Mohammed M.; Goel, Sandeep

    2015-01-01

    Cryostorage is of immense interest in biomedical research, especially for stem cell-based therapies and fertility preservation. Several protocols have been developed for efficient cryopreservation of cells and tissues, and a combination of dimethyl sulfoxide (DMSO) and fetal bovine serum (FBS) is commonly used. However, there is a need for an alternative to FBS because of ethical reasons, high cost, and risk of contamination with blood-borne diseases. The objective of the present study was to examine the possibility of using buffalo (Bubalus bubalis) ocular fluid (BuOF) to replace FBS in cryomedia. Frozen–thawed cells, which were cryopreserved in a cryomedia with BuOF, were assessed for viability, early and late apoptosis, and proliferation. Three cell lines (CHO, HEK, and C18-4), mouse embryonic stem (mES) cells, and primary cells, such as mouse embryonic fibroblast (MEF) cells, human peripheral blood mononuclear cells (hPBMCs), and mouse bone marrow cells (mBMCs), were cryopreserved in cryomedia containing 10% DMSO (D10) with 20% FBS (D10S20) or D10 with 20% BuOF (D10O20). For all three cell lines and mES cells cryopreserved in either D10S20 or D10O20, thawed cells showed no difference in cell viability or cell recovery. Western blot analysis of frozen–thawed-cultured cells revealed that the expression of Annexin V and proliferating cell nuclear antigen (PCNA) proteins, and the ratio of BAX/BCL2 proteins were similar in all three cell lines, mES cells, and hPBMCs cryopreserved in D10S20 and D10O20. However, initial cell viability, cell recovery after culture, and PCNA expression were significantly lower in MEF cells, and the BAX/BCL2 protein ratio was elevated in mBMCs cryopreserved in D10O20. Biochemical and proteomic analysis of BuOF showed the presence of several components that may have roles in imparting the cryoprotective property of BuOF. These results encourage further research to develop an efficient serum-free cryomedia for several cell types using

  13. Lenalidomide, an anti-tumor drug, regulates retinal endothelial cell function: Implication for treating ocular neovascular disorder.

    PubMed

    Dong, Ling-Feng; Yao, Jin; Wang, Xiao-Qun; Shan, Kun; Yang, Hong; Yan, Biao; Jiang, Qin

    2015-10-02

    Ocular angiogenesis is an important pathologic character of several ocular diseases, such as retinopathy of prematurity, diabetic retinopathy and age-related macular degeneration (AMD). Inhibition of ocular angiogenesis has great therapeutic value for treating these dieses. Here we show that lenalidomide, an anti-tumor drug, has great anti-angiogenic potential in ocular diseases. Lenalidomide inhibits retinal endothelial cell viability in normal and pathological condition, and inhibits VEGF-induced endothelial cell migration and tube formation in vitro. Moreover, lenalidomide inhibits ocular angiogenesis in vivo through the reduction of angiogenesis- and inflammation-related protein expression. Collectively, lenalidomide is a promising drug for treating ocular angiogenesis through its anti-proliferative and anti-inflammatory property.

  14. [Ocular manifestations of acute T-cell lymphoblastic leukemia in hematological remission--a case report].

    PubMed

    Siedlińska, Maria; Karska-Basta, Izabella; Pagacz, Dominika; Sobociński, Marcin; Romanowska-Dixon, Bożena

    2014-01-01

    The paper presents a case of a 60 year-old female referred to the Department of Ophthalmology and Ocular Oncology, Medical College, Jagiellonian University in Krakow with the sudden severe vision deterioration in both eyes. The patient was treated for T-cell acute lymphoblastic leukemia at the local Department of Hematology, at that time she was considered to be in hematological remission. Based on findings of clinical examination and additional tests, the patient was diagnosed with leukemic infiltration of the retina and optic nerve with secondary retinal detachment. Systemic and intrathecal chemotherapy as well as local radiotherapy to both eyes were administered. Ocular manifestations of T-cell acute lymphoblastic leukemia may develop in patients in hematological remission. Standard management of leukemic infiltrates involving the retina, choroid and optic nerve includes the intrathecal chemotherapy and lo- cal radiotherapy. Such therapy caused regression and cicatrization of the ocular infiltrates, but did not improve visual acuity in the described patient.

  15. Age-related changes in human vestibulo-ocular reflexes: Sinusoidal rotation and caloric tests

    NASA Technical Reports Server (NTRS)

    Peterka, R. J.; Black, F. O.; Schoenhoff, M. B.

    1989-01-01

    The dynamic response properties of horizontal vestibulo-ocular reflex (VOR) were characterized in 216 human subjects ranging in age from 7 to 81 years. The object of this cross-sectional study was to determine the effects of aging on VOR dynamics, and to identify the distributions of parameters which describe VOR responses to caloric and to sinusoidal rotational stimuli in a putatively normal population. Caloric test parameters showed no consistent trend with age. Rotation test parameters showed declining response amplitude and slightly less compensatory response phase with increasing age. The magnitudes of these changes were not large relative to the variability within the population. The age-related trends in VOR were not consistent with the anatomic changes in the periphery reported by others which showed an increasing rate of peripheral hair cell and nerve fiber loss in subjects over 55 years. The poor correlation between physiological and anatomical data suggest that adaptive mechanisms in the central nervous system are important in maintaining the VOR.

  16. SMOC1 Is Essential for Ocular and Limb Development in Humans and Mice

    PubMed Central

    Okada, Ippei; Hamanoue, Haruka; Terada, Koji; Tohma, Takaya; Megarbane, Andre; Chouery, Eliane; Abou-Ghoch, Joelle; Jalkh, Nadine; Cogulu, Ozgur; Ozkinay, Ferda; Horie, Kyoji; Takeda, Junji; Furuichi, Tatsuya; Ikegawa, Shiro; Nishiyama, Kiyomi; Miyatake, Satoko; Nishimura, Akira; Mizuguchi, Takeshi; Niikawa, Norio; Hirahara, Fumiki; Kaname, Tadashi; Yoshiura, Koh-ichiro; Tsurusaki, Yoshinori; Doi, Hiroshi; Miyake, Noriko; Furukawa, Takahisa; Matsumoto, Naomichi; Saitsu, Hirotomo

    2011-01-01

    Microphthalmia with limb anomalies (MLA) is a rare autosomal-recessive disorder, presenting with anophthalmia or microphthalmia and hand and/or foot malformation. We mapped the MLA locus to 14q24 and successfully identified three homozygous (one nonsense and two splice site) mutations in the SPARC (secreted protein acidic and rich in cysteine)-related modular calcium binding 1 (SMOC1) in three families. Smoc1 is expressed in the developing optic stalk, ventral optic cup, and limbs of mouse embryos. Smoc1 null mice recapitulated MLA phenotypes, including aplasia or hypoplasia of optic nerves, hypoplastic fibula and bowed tibia, and syndactyly in limbs. A thinned and irregular ganglion cell layer and atrophy of the anteroventral part of the retina were also observed. Soft tissue syndactyly, resulting from inhibited apoptosis, was related to disturbed expression of genes involved in BMP signaling in the interdigital mesenchyme. Our findings indicate that SMOC1/Smoc1 is essential for ocular and limb development in both humans and mice. PMID:21194678

  17. Behavior of human horizontal vestibulo-ocular reflex in response to high-acceleration stimuli

    NASA Technical Reports Server (NTRS)

    Maas, E. F.; Huebner, W. P.; Seidman, S. H.; Leigh, R. J.

    1989-01-01

    The horizontal vestibulo-ocular reflex (VOR) during transient, high-acceleration (1900-7100 deg/sec-squared) head rotations was studied in four human subjects. Such stimuli perturbed the angle of gaze and caused illusory movement of a viewed target (oscillopsia). The disturbance of gaze could be attributed to the latency of the VOR (which ranged from 6-15 ms) and inadequate compensatory eye rotations (median VOR gain ranged from 0.61-0.83).

  18. Behavior of human horizontal vestibulo-ocular reflex in response to high-acceleration stimuli

    NASA Technical Reports Server (NTRS)

    Maas, E. F.; Huebner, W. P.; Seidman, S. H.; Leigh, R. J.

    1989-01-01

    The horizontal vestibulo-ocular reflex (VOR) during transient, high-acceleration (1900-7100 deg/sec-squared) head rotations was studied in four human subjects. Such stimuli perturbed the angle of gaze and caused illusory movement of a viewed target (oscillopsia). The disturbance of gaze could be attributed to the latency of the VOR (which ranged from 6-15 ms) and inadequate compensatory eye rotations (median VOR gain ranged from 0.61-0.83).

  19. Human Asymptomatic Epitopes Identified from the Herpes Simplex Virus Tegument Protein VP13/14 (UL47) Preferentially Recall Polyfunctional Effector Memory CD44high CD62Llow CD8+ TEM Cells and Protect Humanized HLA-A*02:01 Transgenic Mice against Ocular Herpesvirus Infection.

    PubMed

    Srivastava, Ruchi; Khan, Arif A; Garg, Sumit; Syed, Sabrina A; Furness, Julie N; Vahed, Hawa; Pham, Tiffany; Yu, Howard T; Nesburn, Anthony B; BenMohamed, Lbachir

    2017-01-15

    Herpes simplex virus 1 (HSV-1) infection is widespread among humans. The HSV-1 virion protein 13/14 (VP13/14), also known as UL47, is a tegument antigen targeted by CD8(+) T cells from HSV-seropositive individuals. However, whether VP13/14-specific CD8(+) T cells play a role in the natural protection seen in asymptomatic (ASYMP) individuals (individuals who have never had a clinical herpetic disease) has not been elucidated. Using predictive computer-assisted algorithms, we identified 10 potential HLA-A*02:01-restricted CD8(+) T-cell epitopes from the 693-amino-acid sequence of the VP13/14 protein. Three out of 10 epitopes exhibited a high to moderate affinity of binding to soluble HLA-A*02:01 molecules. The phenotype and function of CD8(+) T cells specific for each epitope were compared in HLA-A*02:01-positive ASYMP individuals and symptomatic (SYMP) individuals (individuals who have frequent clinical herpetic diseases) using determination of a combination of tetramer frequency and the levels of granzyme B, granzyme K, perforin, gamma interferon, tumor necrosis factor alpha, and interleukin-2 production and CD107(a/b) cytotoxic degranulation. High frequencies of multifunctional CD8(+) T cells directed against three epitopes, VP13/14 from amino acids 286 to 294 (VP13/14286-294), VP13/14 from amino acids 504 to 512 (VP13/14504-512), and VP13/14 from amino acids 544 to 552 (VP13/14544-552), were detected in ASYMP individuals, while only low frequencies were detected in SYMP individuals. The three epitopes also predominantly recalled more CD45RA(low) CD44(high) CCR7(low) CD62L(low) CD8(+) effector memory T cells (TEM cells) in ASYMP individuals than SYMP individuals. Moreover, immunization of HLA-A*02:01 transgenic mice with the three CD8(+) TEM-cell epitopes from ASYMP individuals induced robust and polyfunctional HSV-specific CD8(+) TEM cells associated with strong protective immunity against ocular herpesvirus infection and disease. Our findings outline the

  20. An Ocular Commensal Protects against Corneal Infection by Driving an Interleukin-17 Response from Mucosal γδ T Cells.

    PubMed

    St Leger, Anthony J; Desai, Jigar V; Drummond, Rebecca A; Kugadas, Abirami; Almaghrabi, Fatimah; Silver, Phyllis; Raychaudhuri, Kumarkrishna; Gadjeva, Mihaela; Iwakura, Yoichiro; Lionakis, Michail S; Caspi, Rachel R

    2017-07-18

    Mucosal sites such as the intestine, oral cavity, nasopharynx, and vagina all have associated commensal flora. The surface of the eye is also a mucosal site, but proof of a living, resident ocular microbiome remains elusive. Here, we used a mouse model of ocular surface disease to reveal that commensals were present in the ocular mucosa and had functional immunological consequences. We isolated one such candidate commensal, Corynebacterium mastitidis, and showed that this organism elicited a commensal-specific interleukin-17 response from γδ T cells in the ocular mucosa that was central to local immunity. The commensal-specific response drove neutrophil recruitment and the release of antimicrobials into the tears and protected the eye from pathogenic Candida albicans or Pseudomonas aeruginosa infection. Our findings provide direct evidence that a resident commensal microbiome exists on the ocular surface and identify the cellular mechanisms underlying its effects on ocular immune homeostasis and host defense. Published by Elsevier Inc.

  1. Ocular findings of elderly cases of homozygous sickle-cell disease in Jamaica.

    PubMed Central

    Condon, P I; Serjeant, G R

    1976-01-01

    The ocular fingings in 60 patients with homozygous sickle-cell disease over the age of 40 years have been described. Peripheral retinal vessel disease was common and appeared to increase with age. Retinitis proliferans was common among older patients in the group. Angioid streaks occurred in 13 (22 per cent) patients. PMID:952805

  2. The role of nanotechnology in control of human diseases: perspectives in ocular surface diseases.

    PubMed

    Rai, Mahendra; Ingle, Avinash P; Gaikwad, Swapnil; Padovani, Felipe Hering; Alves, Monica

    2016-10-01

    Nanotechnology is the creation and use of materials and devices on the same scale as molecules and intracellular structures, typically less than 100 nm in size. It is an emerging science and has made its way into pharmaceuticals to significantly improve the delivery and efficacy of drugs in a number of therapeutic areas, due to development of various nanoparticle-based products. In recent years, there has been increasing evidence that nanotechnology can help to overcome many of the ocular diseases and hence researchers are keenly interested in this science. Nanomedicines offer promise as viable alternatives to conventional drops, gels or ointments to improve drug delivery to the eye. Because of their small size, they are well tolerated, thus preventing washout, increase bioavailability and also help in specific drug delivery. This review describes the application of nanotechnology in the control of human diseases with special emphasis on various eye and ocular surfaces diseases.

  3. Aldehyde dehydrogenase inhibition blocks mucosal fibrosis in human and mouse ocular scarring

    PubMed Central

    Ahadome, Sarah D.; Abraham, David J.; Rayapureddi, Suryanarayana; Saw, Valerie P.; Saban, Daniel R.; Calder, Virginia L.; Norman, Jill T.; Ponticos, Markella; Daniels, Julie T.; Dart, John K.

    2016-01-01

    Mucous membrane pemphigoid (MMP) is a systemic mucosal scarring disease, commonly causing blindness, for which there is no antifibrotic therapy. Aldehyde dehydrogenase family 1 (ALDH1) is upregulated in both ocular MMP (OMMP) conjunctiva and cultured fibroblasts. Application of the ALDH metabolite, retinoic acid (RA), to normal human conjunctival fibroblasts in vitro induced a diseased phenotype. Conversely, application of ALDH inhibitors, including disulfiram, to OMMP fibroblasts in vitro restored their functionality to that of normal controls. ALDH1 is also upregulated in the mucosa of the mouse model of scarring allergic eye disease (AED), used here as a surrogate for OMMP, in which topical application of disulfiram decreased fibrosis in vivo. These data suggest that progressive scarring in OMMP results from ALDH/RA fibroblast autoregulation, that the ALDH1 subfamily has a central role in immune-mediated ocular mucosal scarring, and that ALDH inhibition with disulfiram is a potential and readily translatable antifibrotic therapy. PMID:27699226

  4. Human Cathelicidin (LL-37), a Multifunctional Peptide, is Expressed by Ocular Surface Epithelia and has Potent Antibacterial and Antiviral Activity

    PubMed Central

    Gordon, Y. Jerold; Huang, Ling C.; Romanowski, Eric G.; Yates, Kathleen A.; Proske, Rita J.; McDermott, Alison M.

    2006-01-01

    Purpose: This study determined whether LL-37 (cathelicidin)is expressed by conjunctival and corneal epithelia as part of ocular host defense. The antimicrobial activity of LL-37 was also assessed in vitro against Pseudomonas aeruginosa (PA), Staphylococcus aureus (SA), Staphylococcus epidermidis (SE), herpes simplex virus type 1 (HSV-1), and adenovirus (Ad). Methods: Expression of LL-37/hCAP 18 mRNA and LL-37 protein was determined by reverse transcription-polymerase chain reaction (RT-PCR) and immunoblotting, respectively, in scraped human corneal epithelium and primary cultured human corneal and conjunctival epithelial cells. The EC50values for three strains of PA and one each of SA and SE were determined for LL-37. LL-37 antiviral inhibition of HSV-1 and adenovirus was assessed by direct inactivation assays. Toxicity of LL-37 to A549 cells was evaluated by a MTT assay. Results: LL-37/hCAP18 mRNA and LL-37 peptide were expressed by human corneal and conjunctival epithelial cells. Antibacterial activity for LL-37 was demonstrated (EC50values for the three PA strains were 2.8 ± 1.3, 1.9 ± 0.3, and 3.6 ± 2.1; for SA: 1.6 ± 1.5; for SE: 1.3 ± 1.9 μg/ml). LL-37 produced a significant reduction (p < 0.001 ANOVA) in HSV-1 and Ad19 viral titers with distinctly different time-kill curves (p < 0.001). LL-37 (up to 111 μM) produced no toxicity in A549 cells. Conclusions: Corneal and conjunctival epithelia express LL-37 as part of mucosal innate immunity to protect against bacterial and viral ocular infections. PMID:16020269

  5. Autofluorescence lifetime measurements in images of the human ocular fundus

    NASA Astrophysics Data System (ADS)

    Schweitzer, Dietrich; Kolb, Achim; Hammer, Martin

    2001-10-01

    Measurements of the autofluorescence at the fundus prove to be an important tool in early diagnosis and in discovering the pathomechanism, e.g., in age-related macular degeneration. In addition to the action of lipofuscin in the aging process, flavines play an important role as prosthetic groups. As metabolic changes occur at cellular level, patient-specific optimized therapy should be possible according to endogenous fluorophores, before morphological alterations are manifest. As a first tool for the detection of dynamic autofluorescence, a laser scanner opthalmoscope will be presented permitting lifetime measurements at the living human eye-ground under extremely weak detectable light. Considering histograms of lifetimes after excitation at 457.8 nm and determined at the living human eye ground in parapapillary region, a lifetime (rho) approximately equal to 1.38nm was calculated most frequently in the long-wave emission range ((lambda) $GTR550 nm). This points to the main contribution of lipfuscin. If the emission range is extended down to 515 nm, components with longer lifetimes are additionally detectable. Lifetime measurements at a human fundus specimen confirmed the lifetime of 1.38nm in lipfuscin-rich pigment epithelium, whereas the mean lifetime of an intact fundus was 2.04ns. A comparison of lifetimes before, during, and after breathing 100% oxygen results in a quenching of the mean lifetime of 0.15ns by oxygen.

  6. Association of human papilloma virus with pterygia and ocular-surface squamous neoplasia

    PubMed Central

    Di Girolamo, N

    2012-01-01

    There are more microorganisms that colonize the human body than resident cells; some are commensal whereas others are pathogenic. Pathogenic microorganisms are sensed by the innate or adaptive immune system, an immune response is initiated, and the infection is often cleared. Some microorganisms have developed strategies to evade immune defenses, ensuring their long-term survival with potentially devastating consequences for the host. Approximately 18% of all cancers can be attributed to infective agents; the most common being Helicobacter pylori, Human papilloma virus (HPV) and Hepatitis B and C virus in causing stomach, cervical and liver carcinoma, respectively. This review focuses on whether HPV infection is necessary for initiating pterygia, a common benign condition and ocular-surface squamous neoplasia (OSSN), a rare disease with metastatic potential. The search engine PubMed was used to identify articles from the literature related to HPV and pterygium or conjunctival neoplasia. From 34 investigations that studied HPV in pterygia and OSSN, a prevalence rate of 18.6% (136/731) and 33.8% (144/426), respectively, was recorded. The variation in HPV prevalence (0–100%) for both disease groups may have arisen from study-design faults and the techniques used to identify the virus. Overall, the data suggest that HPV is not necessary for initiating either condition but may be a co-factor in susceptible hosts. Currently, over 60 million people worldwide have been immunized with HPV vaccines, but any effect on pterygium and OSSN development may not be known for some time as these lesions can evolve over decades or occur in older individuals. PMID:22134594

  7. Ocular myasthenia gravis induced by human acetylcholine receptor ϵ subunit immunization in HLA DR3 transgenic mice.

    PubMed

    Wu, Xiaorong; Tuzun, Erdem; Saini, Shamsher S; Wang, Jun; Li, Jing; Aguilera-Aguirre, Leopoldo; Huda, Ruksana; Christadoss, Premkumar

    2015-12-01

    Extraocular muscles (EOM) are preferentially involved in myasthenia gravis (MG) and acetylcholine receptor (AChR) antibody positive MG patients may occasionally present with isolated ocular symptoms. Although experimental autoimmune myasthenia gravis (EAMG) induced by whole AChR immunization closely mimics clinical and immunopathological aspects of MG, EOM are usually not affected. We have previously developed an EAMG model, which imitates EOM symptoms of MG by immunization of human leukocyte antigen (HLA) transgenic mice with α or γ-subunits of human AChR (H-AChR). To investigate the significance of the ϵ-subunit in ocular MG, we immunized HLA-DR3 and HLA-DQ8 transgenic mice with recombinant H-AChR ϵ-subunit expressed in Escherichia coli. HLA-DR3 transgenic mice showed significantly higher clinical ocular and generalized MG severity scores and lower grip strength values than HLA-DQ8 mice. H-AChR ϵ-subunit-immunized HLA-DR3 transgenic mice had higher serum anti-AChR antibody (IgG, IgG1, IgG2b, IgG2c and IgM) levels, neuromuscular junction IgG and complement deposit percentages than ϵ-subunit-immunized HLA-DQ8 transgenic mice. Control mice immunized with E. coli extract or complete Freund adjuvant (CFA) did not show clinical and immunopathological features of ocular and generalized EAMG. Lymph node cells of ϵ-subunit-immunized HLA-DR3 mice showed significantly higher proliferative responses than those of ϵ-subunit-immunized HLA-DQ8 mice, crude E. coli extract-immunized and CFA-immunized transgenic mice. Our results indicate that the human AChR ϵ-subunit is capable of inducing myasthenic muscle weakness. Diversity of the autoimmune responses displayed by mice expressing different HLA class II molecules suggests that the interplay between HLA class II alleles and AChR subunits might have a profound impact on the clinical course of MG.

  8. Mutant human myocilin induces strain specific differences in ocular hypertension and optic nerve damage in mice.

    PubMed

    McDowell, Colleen M; Luan, Tomi; Zhang, Zhang; Putliwala, Tasneem; Wordinger, Robert J; Millar, J Cameron; John, Simon W M; Pang, Iok-Hou; Clark, Abbot F

    2012-07-01

    Elevated intraocular pressure (IOP) is a causative risk factor for the development and progression of glaucoma. Glaucomatous mutations in myocilin (MYOC) damage the trabecular meshwork and elevate IOP in humans and in mice. Animal models of glaucoma are important to discover and better understand molecular pathogenic pathways and to test new glaucoma therapeutics. Although a number of different animal models of glaucoma have been developed and characterized, there are no true models of human primary open angle glaucoma (POAG). The overall goal of this work is to develop the first inducible mouse model of POAG using a human POAG relevant transgene (i.e. mutant MYOC) expression in mouse eyes to elevate IOP and cause pressure-induced damage to the optic nerve. Four mouse strains (A/J, BALB/cJ, C57BL/6J, and C3H/HeJ) were used in this study. Ad5.MYOC.Y437H (5 × 10(7) pfu) was injected intravitreally into one eye, with the uninjected contralateral eye serving as the control eye. Conscious IOP measurements were taken using a TonoLab rebound tonometer. Optic nerve damage was determined by scoring PPD stained optic nerve cross sections. Retinal ganglion cell and superior colliculus damage was assessed by Nissl stain cell counts. Intravitreal administration of viral vector Ad5.MYOC.Y437H caused a prolonged, reproducible, and statistically significant IOP elevation in BALB/cJ, A/J, and C57BL/6J mice. IOPs increased to approximately 25 mm Hg for 8 weeks (p < 0.0001). In contrast, the C3H/HeJ mouse strain was resistant to Ad5.MYOC.Y437H induced IOP elevation for the 8-week time period. IOPs were stable (12-15 mm Hg) in the uninjected control eyes. We also determined whether there were any strain differences in pressure-induced optic nerve damage. Even though IOP was similarly elevated in three of the strains tested (BALB/cJ, C57BL/6J, and A/J) only the A/J strain had considerable and significant optic nerve damage at the end of 8 weeks with optic nerve damage score of 2.64

  9. Immunoglobulin concentrations in human tears in ocular diseases.

    PubMed Central

    Sen, D K; Sarin, G S

    1979-01-01

    Immunoglobulin concentrations in human tears were determined in 165 patients with different eye diseases by a standard radial immunodiffusion method. IgA was present in all the samples in measurable quantity. The mean IgA values were significantly higher than the controls in patients with acute bacterial conjunctivitis, keratomalacia, corneal graft reaction, blepharoconjunctivitis, and acute keratoconjunctivitis. The values in the patients with vernal conjunctivitis, phlyctenular conjunctivitis, acute bacterial corneal ulcer, and acute endogenous uveitis were not significantly different from those in the controls. IgG could be detected in the majority of the samples but it was in measurable quantity in 18 samples. IgM could be detected in fewer samples. IgD was not detected in any of them. The study indicates that, whenever the immunoglobulin levels in tears are altered in diseased eyes, it is the IgA level that is predominantly altered and not the IgG level. PMID:465402

  10. Immunoglobulin concentrations in human tears in ocular diseases.

    PubMed

    Sen, D K; Sarin, G S

    1979-05-01

    Immunoglobulin concentrations in human tears were determined in 165 patients with different eye diseases by a standard radial immunodiffusion method. IgA was present in all the samples in measurable quantity. The mean IgA values were significantly higher than the controls in patients with acute bacterial conjunctivitis, keratomalacia, corneal graft reaction, blepharoconjunctivitis, and acute keratoconjunctivitis. The values in the patients with vernal conjunctivitis, phlyctenular conjunctivitis, acute bacterial corneal ulcer, and acute endogenous uveitis were not significantly different from those in the controls. IgG could be detected in the majority of the samples but it was in measurable quantity in 18 samples. IgM could be detected in fewer samples. IgD was not detected in any of them. The study indicates that, whenever the immunoglobulin levels in tears are altered in diseased eyes, it is the IgA level that is predominantly altered and not the IgG level.

  11. Analysis of the volumetric relationship among human ocular, orbital and fronto-occipital cortical morphology.

    PubMed

    Masters, Michael; Bruner, Emiliano; Queer, Sarah; Traynor, Sarah; Senjem, Jess

    2015-10-01

    Recent research on the visual system has focused on investigating the relationship among eye (ocular), orbital, and visual cortical anatomy in humans. This issue is relevant in evolutionary and medical fields. In terms of evolution, only in modern humans and Neandertals are the orbits positioned beneath the frontal lobes, with consequent structural constraints. In terms of medicine, such constraints can be associated with minor deformation of the eye, vision defects, and patterns of integration among these features, and in association with the frontal lobes, are important to consider in reconstructive surgery. Further study is therefore necessary to establish how these variables are related, and to what extent ocular size is associated with orbital and cerebral cortical volumes. Relationships among these anatomical components were investigated using magnetic resonance images from a large sample of 83 individuals, which also included each subject's body height, age, sex, and uncorrected visual acuity score. Occipital and frontal gyri volumes were calculated using two different cortical parcellation tools in order to provide a better understanding of how the eye and orbit vary in relation to visual cortical gyri, and frontal cortical gyri which are not directly related to visual processing. Results indicated that ocular and orbital volumes were weakly correlated, and that eye volume explains only a small proportion of the variance in orbital volume. Ocular and orbital volumes were also found to be equally and, in most cases, more highly correlated with five frontal lobe gyri than with occipital lobe gyri associated with V1, V2, and V3 of the visual cortex. Additionally, after accounting for age and sex variation, the relationship between ocular and total visual cortical volume was no longer statistically significant, but remained significantly related to total frontal lobe volume. The relationship between orbital and visual cortical volumes remained significant for a

  12. Ocular penetration of topically applied norfloxacin 0.3% in the rabbits and in humans.

    PubMed

    Bron, A M; Péchinot, A; Garcher, C; Guyonnet, G; Kazmierczak, A

    1992-01-01

    The kinetics of topically applied norfloxacin 0.3 percent were studied in rabbit and man. All measurements were performed by high-pressure liquid chromatography. Norfloxacin concentrations were investigated five to 120 minutes in rabbit ocular tissues after instillation of a single drop. In normal eyes, after 30 minutes, mean +/- SEM levels were 14.3 +/- 3.7 micrograms/g in cornea, 3.3 +/- 0.7 micrograms/g in conjunctiva, 0.2 +/- 0.1 microgram/g in aqueous humor. After removal of the corneal epithelium concentrations were as follows: 84.2 +/- 15.8 micrograms/g, 7.3 +/- 2.3 micrograms/g, 8.6 +/- 1.9 micrograms/g respectively. Penetration in posterior ocular tissues were rather poor. In human eyes, the intracorneal concentrations were assessed in patients being operated on corneal grafts. After instillation of 5 drops, the concentration in cornea was 15.5 +/- 2.1 micrograms/g. These data show that therapeutic levels of norfloxacin can be achieved in anterior ocular tissues, which may be of help in superficial infections of the eye.

  13. Mineralocorticoid receptor is involved in rat and human ocular chorioretinopathy

    PubMed Central

    Zhao, Min; Célérier, Isabelle; Bousquet, Elodie; Jeanny, Jean-Claude; Jonet, Laurent; Savoldelli, Michèle; Offret, Olivier; Curan, Antoine; Farman, Nicolette; Jaisser, Frédéric; Behar-Cohen, Francine

    2012-01-01

    Central serous chorioretinopathy (CSCR) is a vision-threatening eye disease with no validated treatment and unknown pathogeny. In CSCR, dilation and leakage of choroid vessels underneath the retina cause subretinal fluid accumulation and retinal detachment. Because glucocorticoids induce and aggravate CSCR and are known to bind to the mineralocorticoid receptor (MR), CSCR may be related to inappropriate MR activation. Our aim was to assess the effect of MR activation on rat choroidal vasculature and translate the results to CSCR patients. Intravitreous injection of the glucocorticoid corticosterone in rat eyes induced choroidal enlargement. Aldosterone, a specific MR activator, elicited the same effect, producing choroid vessel dilation -and leakage. We identified an underlying mechanism of this effect: aldosterone upregulated the endothelial vasodilatory K channel KCa2.3. Its blockade prevented aldosterone-induced thickening. To translate these findings, we treated 2 patients with chronic nonresolved CSCR with oral eplerenone, a specific MR antagonist, for 5 weeks, and observed impressive and rapid resolution of retinal detachment and choroidal vasodilation as well as improved visual acuity. The benefit was maintained 5 months after eplerenone withdrawal. Our results identify MR signaling as a pathway controlling choroidal vascular bed relaxation and provide a pathogenic link with human CSCR, which suggests that blockade of MR could be used therapeutically to reverse choroid vasculopathy. PMID:22684104

  14. Ocular torsion measured by TV- and scanning laser ophthalmoscopy during horizontal pursuit in humans and monkeys.

    PubMed

    Ott, D; Eckmiller, R

    1989-12-01

    Ocular torsion during horizontal foveal pursuit and fixation was measured in five human subjects and two trained monkeys (Macaca fascicularis) by direct analysis of the ocular fundus rotation. In the monkeys the fundus images of either eye were generated with a TV-ophthalmoscope while the contralateral eye pursued an 8' visual target moving sinusoidally (0.3-0.9 Hz, +/- 5 degrees) in the horizontal plane. In the humans a scanning laser ophthalmoscope (SLO) generated the fundus image of the ipsilateral eye, which pursued the visual target (same parameters as in the monkeys) mixed electronically into the laser scan raster. The image sequences were stored on videotape and subjected to a frame-by-frame rotation analysis. In both the humans and the monkeys, torsion (fundus rotation about the visual axis) sinusoidally modulated (up to 8 degrees peak-to-peak) during foveal pursuit, approximately in phase with horizontal eye position. Intorsion (nasal movement of the upper eye pole) or extorsion was found during pursuit in the temporal or nasal direction. Torsion showed considerable intra-individual fluctuation and interindividual variability with regard to phase and modulation depth relative to the pursuit movements, and was interspersed with irregularly occurring rapid deflections. Torsion of the conjugate, nonpursing eye was similar to torsion of the pursuing eye. In contrast, torsion during fixation was only loosely correlated with horizontal eye position. Slow torsional drifts and large, rapid deflections (up to 6 degrees) occurred in either direction at a given fixation point in the horizontal plane. We conclude that ocular torsion during horizontal pursuit in primates is actively generated by a separate, neural oculomotor subsystem.(ABSTRACT TRUNCATED AT 250 WORDS)

  15. Mutation of SALL2 causes recessive ocular coloboma in humans and mice

    PubMed Central

    Kelberman, Daniel; Islam, Lily; Lakowski, Jörn; Bacchelli, Chiara; Chanudet, Estelle; Lescai, Francesco; Patel, Aara; Stupka, Elia; Buck, Anja; Wolf, Stephan; Beales, Philip L.; Jacques, Thomas S.; Bitner-Glindzicz, Maria; Liasis, Alki; Lehmann, Ordan J.; Kohlhase, Jürgen; Nischal, Ken K.; Sowden, Jane C.

    2014-01-01

    Ocular coloboma is a congenital defect resulting from failure of normal closure of the optic fissure during embryonic eye development. This birth defect causes childhood blindness worldwide, yet the genetic etiology is poorly understood. Here, we identified a novel homozygous mutation in the SALL2 gene in members of a consanguineous family affected with non-syndromic ocular coloboma variably affecting the iris and retina. This mutation, c.85G>T, introduces a premature termination codon (p.Glu29*) predicted to truncate the SALL2 protein so that it lacks three clusters of zinc-finger motifs that are essential for DNA-binding activity. This discovery identifies SALL2 as the third member of the Drosophila homeotic Spalt-like family of developmental transcription factor genes implicated in human disease. SALL2 is expressed in the developing human retina at the time of, and subsequent to, optic fissure closure. Analysis of Sall2-deficient mouse embryos revealed delayed apposition of the optic fissure margins and the persistence of an anterior retinal coloboma phenotype after birth. Sall2-deficient embryos displayed correct posterior closure toward the optic nerve head, and upon contact of the fissure margins, dissolution of the basal lamina occurred and PAX2, known to be critical for this process, was expressed normally. Anterior closure was disrupted with the fissure margins failing to meet, or in some cases misaligning leading to a retinal lesion. These observations demonstrate, for the first time, a role for SALL2 in eye morphogenesis and that loss of function of the gene causes ocular coloboma in humans and mice. PMID:24412933

  16. Lenalidomide, an anti-tumor drug, regulates retinal endothelial cell function: Implication for treating ocular neovascular disorder

    SciTech Connect

    Dong, Ling-Feng; Yao, Jin; Wang, Xiao-Qun; Shan, Kun; Yang, Hong; Yan, Biao; Jiang, Qin

    2015-10-02

    Ocular angiogenesis is an important pathologic character of several ocular diseases, such as retinopathy of prematurity, diabetic retinopathy and age-related macular degeneration (AMD). Inhibition of ocular angiogenesis has great therapeutic value for treating these dieses. Here we show that lenalidomide, an anti-tumor drug, has great anti-angiogenic potential in ocular diseases. Lenalidomide inhibits retinal endothelial cell viability in normal and pathological condition, and inhibits VEGF-induced endothelial cell migration and tube formation in vitro. Moreover, lenalidomide inhibits ocular angiogenesis in vivo through the reduction of angiogenesis- and inflammation-related protein expression. Collectively, lenalidomide is a promising drug for treating ocular angiogenesis through its anti-proliferative and anti-inflammatory property. - Highlights: • Lenalidomide inhibits retinal endothelial cell viability in vitro. • Lenalidomide inhibits retinal endothelial cell migration and tube formation. • Lenalidomide inhibits pathological ocular angiogenesis in vivo. • Lenalidomide inhibits angiogenesis- and inflammation-related protein expression.

  17. Granulocytes in Ocular HSV-1 Infection: Opposing Roles of Mast Cells and Neutrophils

    PubMed Central

    Royer, Derek J.; Zheng, Min; Conrady, Christopher D.; Carr, Daniel J. J.

    2015-01-01

    Purpose. The contributions of mast cells (MCs) to immunologic defense against pathogens in the eye are unknown. We have characterized pericorneal MCs as tissue-resident innate sentinels and determined their impact on the immune response to herpes simplex virus type-1 (HSV-1), a common ocular pathogen. Methods. The impact of mast cells on the immune response to HSV-1 infection was investigated using MC-deficient KitW-sh mice. Virus titers, inflammatory cytokine production, eicosanoid profiles, cellular immune responses, and ocular pathology were evaluated and compared with C57BL/6J mice during an acute corneal HSV-1 infection. Results. Corneas of KitW-sh mice have higher viral titers, increased edema, and greater leukocyte infiltration following HSV-1 infection. Following infection, cytokine profiles were slightly elevated overall in KitW-sh mice. Eicosanoid profiles were remarkably different only when comparing uninfected corneas from both groups. Neutrophils within infected corneas expressed HSV-1 antigen, lytic genes, and served as a disease-causing vector when adoptively transferred into immunocompromised animals. Myeloid-derived suppressor cells did not infiltrate into the cornea or suppress the expansion, recruitment, or cytokine production by CD8+ T cells following acute HSV-1 infection. Conclusions. Collectively, these findings provide new insight into host defense in the cornea and the pathogenesis of HSV-1 infection by identifying previously unacknowledged MCs as protective innate sentinels for infection of the ocular surface and reinforcing that neutrophils are detrimental to corneal infection. PMID:26066745

  18. Ocular molecules and cells that regulate immune responses in situ.

    PubMed

    Streilein, J W; Cousins, S; Williamson, J S

    1990-10-01

    Regulation of T cell-dependent immune responses is mediated in part by bone marrow-derived antigen presenting cells (APC) that (a) process and present antigens which engage the T cell receptor and (b) secrete cytokines that influence the threshold of T cell activation. The anterior chamber of the eye is lined by the corneal endothelium (which rests on a stroma and epithelium that is devoid of class II MHC + APC) and iris/ciliary body (which contain significant numbers of bone marrow-derived cells, one third of which are class II MHC +). When tested in vitro, these potential APCs fail to present antigens in a form that activates T cells. Moreover, iris/ciliary body cells actually suppress activation of T cells exposed to antigens on conventional APC. In addition, aqueous humor under normal circumstances contains factors (one of which is TGFB) that are potent inhibitors of antigen-driven T cell activation, but spare other aspects of T cell function. Evidence suggests that the bone marrow-derived cells in iris/ciliary body are the source of this factor. Thus, the anterior chamber contains powerful forces that can prevent induction and can suppress expression of T cell mediated immunity. It is proposed that these forces are responsible for immunologic privilege and anterior chamber associated immune deviation, and for suppressing pathologic proliferation and inflammation in the anterior segment of the eye.

  19. Dynamic properties of the human vestibulo-ocular reflex during head rotations in roll

    NASA Technical Reports Server (NTRS)

    Seidman, S. H.; Leigh, R. J.; Tomsak, R. L.; Grant, M. P.; Dell'Osso, L. F.

    1995-01-01

    We investigated the dynamic properties of the human vestibulo-ocular reflex (VOR) during roll head rotations in three human subjects using the magnetic search coil technique. In the first of two experiments, we quantify the behavior of the ocular motor plant in the torsional plane. The subject's eye was mechanically displaced into intorsion, extorsion or abduction, and the dynamic course of return of the eye to its resting position was measured. The mean predominant time constants of return were 210 msec from intorsion, 83 msec from extorsion, and 217 msec from abduction, although there was considerable variability of results from different trials and subjects. In the second experiment, we quantify the efficacy of velocity-to-position integration of the vestibular signal. Position-step stimuli were used to test the torsional or horizontal VOR, being applied with subjects heads erect or supine. After a torsional position-step, the eye drifted back to its resting position, but after a horizontal position-step the eye held its new horizontal position. To interpret these responses we used a simple model of the VOR with parameters of the ocular motor plant set to values determined during Exp 1. The time constant of the velocity-to-position neural integrator was smaller (typically 2 sec) in the torsional plane than in the horizontal plane (> 20 sec). No disconjugacy of torsional eye movements was observed. Thus, the dynamic properties of the VOR in roll differ significantly from those of the VOR in yaw, reflecting different visual demands placed on this reflex in these two planes.

  20. Dynamic properties of the human vestibulo-ocular reflex during head rotations in roll

    NASA Technical Reports Server (NTRS)

    Seidman, S. H.; Leigh, R. J.; Tomsak, R. L.; Grant, M. P.; Dell'Osso, L. F.

    1995-01-01

    We investigated the dynamic properties of the human vestibulo-ocular reflex (VOR) during roll head rotations in three human subjects using the magnetic search coil technique. In the first of two experiments, we quantify the behavior of the ocular motor plant in the torsional plane. The subject's eye was mechanically displaced into intorsion, extorsion or abduction, and the dynamic course of return of the eye to its resting position was measured. The mean predominant time constants of return were 210 msec from intorsion, 83 msec from extorsion, and 217 msec from abduction, although there was considerable variability of results from different trials and subjects. In the second experiment, we quantify the efficacy of velocity-to-position integration of the vestibular signal. Position-step stimuli were used to test the torsional or horizontal VOR, being applied with subjects heads erect or supine. After a torsional position-step, the eye drifted back to its resting position, but after a horizontal position-step the eye held its new horizontal position. To interpret these responses we used a simple model of the VOR with parameters of the ocular motor plant set to values determined during Exp 1. The time constant of the velocity-to-position neural integrator was smaller (typically 2 sec) in the torsional plane than in the horizontal plane (> 20 sec). No disconjugacy of torsional eye movements was observed. Thus, the dynamic properties of the VOR in roll differ significantly from those of the VOR in yaw, reflecting different visual demands placed on this reflex in these two planes.

  1. ­­Presence and distribution of 14-3-3 proteins in human ocular surface tissues

    PubMed Central

    Shankardas, Jwalitha; Senchyna, Michelle

    2008-01-01

    Purpose 14–3-3 is a highly conserved, ubiquitously expressed family of proteins. At least seven mammalian isoforms (β, ε, γ, η, θ, σ, and ζ) are known. These proteins associate with over 200 different target molecules and activate several downstream signaling cascades involved in the regulation of metabolism, cell cycle, apoptosis, protein trafficking, transcription, stress responses, and malignant transformations. We are interested in the role of these proteins in the mechanisms regulating homeostasis and the pathologies of the human ocular surface. Therefore, our purpose is to determine the expression of the 14–3-3 proteins in the human cornea, the conjunctiva, and the primary cells comprising these tissues. Methods Using immunofluorescence, we determined the expression of 14–3-3 β, ε, γ, η, θ, σ, and ζ in paraffin sections of the human cornea and conjunctiva. Using indirect immunofluorescence and western blot analysis, we also determined the expression of these isoforms in primary corneal epithelial cells, keratocytes, endothelial cells, and primary conjunctival epithelial cells. The expressions of these isoforms in primary epithelial and endothelial cells were compared with the same expressions in several corneal cell lines. Western blot analysis was used to determine the presence of 14–3-3 isoforms in the culture medium from corneal epithelial cells, cell lines, and the tear fluid. Results All the 14–3-3 isoforms were expressed in the corneal and conjunctival epithelia as well as primary epithelial cells and cell lines. Expression of 14–3-3 σ was confined to epithelial cells and was secreted into the culture medium of primary cells and cell lines. We also report for the first time that two of the secreted isoforms, 14–3-3 γ and ζ, are also present in the human tear fluid. Conclusions We have determined that all the mammalian 14–3-3 isoforms are expressed in the human cornea, conjunctiva, and the component cells and that the 14

  2. Effect of human apolipoprotein E genotype on the pathogenesis of experimental ocular HSV-1

    PubMed Central

    Bhattacharjee, Partha S.; Neumann, Donna M.; Foster, Timothy P.; Bouhanik, Sadallah; Clement, Christian; Vinay, Dass; Thompson, Hilary W.; Hill, James M.

    2008-01-01

    The isoform-specific role of human apolipoprotein E (apoE) has been assessed in a mouse model of ocular herpes. Female, age-matched transgenic mice knocked-in for the human allele apoE3 or apoE4 and their parent C57Bl/6 mice were inoculated corneally with HSV-1 strain KOS. Ocular HSV-1 pathogenesis was monitored through viral replication and clinical progression of stromal opacity and neovascularization by slit-lamp examination. Establishment of latency was determined by analysis of HSV-1 DNA (copy number) by specific real-time PCR in the cornea, trigeminal ganglia (TG), and brain. Representative groups of transgenic mice were sacrificed for the analysis of gene expression of vascular endothelial growth factor (VEGF) by reverse-transcription PCR, and apoE expression by Western blot analysis. At 6 days post-infection (P.I.), the ocular infectious HSV-1 titer was significantly higher (p < 0.05) in apoE4 mice compared with apoE3 and C57Bl/6 mice. Corneal neovascularization in apoE4 mice was significantly higher (p < 0.05) than apoE3 and C57Bl/6 mice. The onset of corneal opacity in apoE4 mice was accelerated during days 9--11 P.I.; however, no significant difference in severity was seen on P.I. days 15 and beyond. At 28 days P.I., infected mice of all genotypes had no significant differences in copy numbers (range 0--15) of HSV-1 DNA in their corneas, indicating that HSV-1 DNA copy numbers in cornea are independent of apoE isoform regulation. At 28 days P.I., both apoE4 and C57Bl/6 mice had a significantly higher (p = 0.001) number of copies of HSV-1 DNA in TG compared with apoE3. ApoE4 mice also had significantly higher (p = 0.001) copies of HSV-1 DNA in their TGs compared with C57Bl/6 mice. In brain, both apoE4 and C57Bl/6 mice had significantly higher numbers (p ≤ 0.03) of copies of HSV-1 DNA compared with apoE3 mice. However, the number of HSV-1 DNA copies in the brain of C57Bl/6 mice was not significantly different than that of apoE4 (p = 0.1). Comparative

  3. Human subcutaneous/ocular dirofilariasis in the Russian Federation and Belarus, 1997-2013.

    PubMed

    Kartashev, Vladimir; Tverdokhlebova, Tatiana; Korzan, Alla; Vedenkov, Andrey; Simón, Luis; González-Miguel, Javier; Morchón, Rodrigo; Siles-Lucas, Mar; Simón, Fernando

    2015-04-01

    This study was performed to determine the yearly frequency, trends in spread, and clinical-epidemiological characteristics of human subcutaneous/ocular dirofilariasis (HSOD) in the Russian Federation and Belarus. The surveillance data of HSOD cases occurring between January 1997 and June 2013, obtained from the regional health administrations of the Russian Federation and Belarus, were analyzed. The spatial distribution of cases was assessed using a GIS map, and the clinical-epidemiological characteristics were defined using 719 cases for which information on anatomical location, age, sex, and area of residence was available. The statistical analysis was performed using the Chi-square test. One thousand two hundred and seventy-two clinical cases of HSOD were identified, the majority of them reported in the south-western regions of the Russian Federation. The disease has spread into northern areas, changing its limit from latitude 45°N in 1997 to latitude 61°N in 2013. The statistical analysis of the data showed that the disease is more frequent in the ocular location, in women, in patients aged between 41 and 60 years, and in patients living in urban areas. Alternative sources to the scientific literature could be necessary to assess the epidemiological situation regarding HSOD in some areas where it has become an emerging condition. There is an urgent need for uniform criteria for reporting and retrieving human cases of dirofilariasis. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  4. Optimised laser microdissection of the human ocular surface epithelial regions for microarray studies

    PubMed Central

    2013-01-01

    Background The most important challenge of performing insitu transcriptional profiling of the human ocular surface epithelial regions is obtaining samples in sufficient amounts, without contamination from adjacent tissue, as the region of interest is microscopic and closely apposed to other tissues regions. We have effectively collected ocular surface (OS) epithelial tissue samples from the Limbal Epithelial Crypt (LEC), limbus, cornea and conjunctiva of post-mortem cadaver eyes with laser microdissection (LMD) technique for gene expression studies with spotted oligonucleotide microarrays and Gene 1.0 ST arrays. Methods Human donor eyes (4 pairs for spotted oligonucleotide microarrays, 3 pairs for Gene 1.0 ST arrays) consented for research were included in this study with due ethical approval of the Nottingham Research Ethics Committee. Eye retrieval was performed within 36 hours of post-mortem period. The dissected corneoscleral buttons were immersed in OCT media and frozen in liquid nitrogen and stored at −80°C till further use. Microscopic tissue sections of interest were taken on PALM slides and stained with Toluidine Blue for laser microdissection with PALM microbeam systems. Optimisation of the laser microdissection technique was crucial for efficient and cost effective sample collection. Results The starting concentration of RNA as stipulated by the protocol of microarray platforms was taken as the cut-off concentration of RNA samples in our studies. The area of LMD tissue processed for spotted oligonucleotide microarray study ranged from 86,253 μm2 in LEC to 392,887 μm2 in LEC stroma. The RNA concentration of the LMD samples ranged from 22 to 92 pg/μl. The recommended starting concentration of the RNA samples used for Gene 1.0 ST arrays was 6 ng/5 μl. To achieve the desired RNA concentration the area of ocular surface epithelial tissue sample processed for the Gene 1.0 ST array experiments was approximately 100,0000 μm2 to 130,0000 μm2. RNA

  5. Ocular transfer of retinal glial cells transduced ex vivo with adenovirus expressing viral IL-10 or CTLA4-Ig inhibits experimental autoimmune uveoretinitis.

    PubMed

    Verwaerde, C; Naud, M-C; Delanoye, A; Wood, M; Thillaye-Goldenberg, B; Auriault, C; de Kozak, Y

    2003-11-01

    Gene transfer using immunomodulatory molecules is a promising tool for in vivo regulation of immune responses. Experimental autoimmune uveitis (EAU), which serves as a model for human ocular inflammation, is induced by systemic immunization with autoantigens, but its expression is restricted to the eye. Previously, we reported protection of rodents against EAU by intravenous or/and periocular injection of vIL-10-expressing adenovirus. Here, the expression of vIL-10 was targeted into the rat Lewis eye, by intravitreal injection of either the free virus or ex vivo transfected retinal Müller glial cells (RMG-vIL-10). As shown using GFP-expressing adenovirus, a longer expression of transgene was observed in the eye after transfer of transfected syngeneic RMG cells than was seen after injection of free virus. Intravitreal injection of RMG-vIL-10 led to significant decrease in ocular pathological manifestations, compared to control RMG cells. This was observed when cells were injected simultaneously with autoantigen, but also after a delayed administration of transfected cells. Finally, injection of RMG cells transfected with adenovirus expressing CTLA4 had a strongly protective effect. In conclusion, inhibition of antigen presentation at the site of expression of the autoimmune disorders represents an attractive alternative to treat ocular inflammation, and the transfer of ex vivo genetically modified cells provides a promising method to target the factor of interest into the eye.

  6. Using stem cells to mend the retina in ocular disease.

    PubMed

    Bull, Natalie D; Martin, Keith R

    2009-11-01

    Retinal degenerative diseases are the leading cause of incurable blindness worldwide. Furthermore, existing pharmacological and surgical interventions are only partially effective in halting disease progression, thus adjunctive neuroprotective strategies are desperately needed to preserve vision. Stem cells appear to possess inherent neuroprotective abilities, at least in part by providing neurotrophic support to injured neurons. Advances in stem cell biology offer the hope of new therapies for a broad range of neurodegenerative conditions, including those of the retina. Experimental cell-mediated therapies also hint at the tantalizing possibility of achieving retinal neuronal replacement and regeneration, once cells are lost to the disease process. This article summarizes the latest advances in cell therapies for neuroprotection and regeneration in neurodegenerative pathologies of both the inner and outer retina.

  7. Fibrin glue inhibits migration of ocular surface epithelial cells.

    PubMed

    Yeung, A M; Faraj, L A; McIntosh, O D; Dhillon, V K; Dua, H S

    2016-10-01

    PurposeFibrin glue has been used successfully in numerous ophthalmic surgical procedures. Recently, fibrin glue has been used in limbal stem cell transplantation to reduce both operative time and to negate the need for sutures. The aim of this study was to determine the effects of fibrin glue on epithelial cell migration in vitro.MethodsCorneoscleral rims were split to retain the epithelial layer, Bowman's layer, and anterior stroma. Rims were cut into eight equal-sized pieces and were placed directly on culture plates or affixed with fibrin glue. Rims were maintained in culture for 25 days and epithelial cell growth was monitored. Cells were photographed to measure area or growth and immunofluorescence staining of explants for fibrin was performed.ResultsExplants that were glued demonstrated significantly delayed epithelial cell growth and migration as compared with explants without glue. By day 16, all fibrin glue had dissolved and coincided with onset of cell growth from glued explants. Cell growth commenced between days 3 and 4 for control explants without glue and around days 14-16 for explants with fibrin glue.ConclusionsFibrin glue delays epithelial cell migration by acting as a physical barrier and can potentially interfere with explant-derived limbal epithelial cell migration on to the corneal surface. We propose that glue should be used to attach the conjunctival frill of the limbal explant but care should be taken to ensure that the glue does not wrap around the explant if used to secure the explant as well. Strategic use of glue, to attach the recessed conjunctiva, can be advantageous in delaying conjunctival cell migration and reducing the need for sequential sector conjunctival epitheliectomy.

  8. Rebamipide suppresses PolyI:C-stimulated cytokine production in human conjunctival epithelial cells.

    PubMed

    Ueta, Mayumi; Sotozono, Chie; Yokoi, Norihiko; Kinoshita, Shigeru

    2013-09-01

    We previously documented that ocular surface epithelial cells could regulate ocular surface inflammation and suggested that, while Toll-like receptor 3 upregulates, EP3, one of the prostaglandin E2 receptors, downregulates ocular surface inflammation. Others reported that rebamipide, a gastroprotective drug, could not only increase the gastric mucus production, but also suppressed gastric mucosal inflammation and that it was dominantly distributed in mucosal tissues. The eyedrop form of rebamipide, approved in Japan for use in the treatment of dry eye diseases, upregulates mucin secretion and production, thereby suppressing superficial punctate keratopathy on the ocular surface of patients with this disease. In the current study, we investigated whether rebamipide has anti- inflammatory effects on the ocular surface. To examine the effects of rebamipide on polyI:C-induced cytokine expression by primary human conjunctival epithelial cells, we used enzyme-linked immunosorbent assay and quantitative reverse transcription-polymerase chain reaction assay. We studied the effects of rebamipide on ocular surface inflammation in our murine experimental allergic conjunctivitis (EAC) model. Rebamipide could suppress polyI:C-induced cytokine production and the expression of mRNAs for CXCL10, CXCL11, RANTES, MCP-1, and IL-6 in human conjunctival epithelial cells. In our EAC model, the topical administration of rebamipide suppressed conjunctival allergic eosinophil infiltration. The topical application of rebamipide on the ocular surface might suppress ocular surface inflammation by suppressing the production of cytokines by ocular surface epithelial cells.

  9. Conjugation of cell-penetrating peptides with poly(lactic-co-glycolic acid)-polyethylene glycol nanoparticles improves ocular drug delivery.

    PubMed

    Vasconcelos, Aimee; Vega, Estefania; Pérez, Yolanda; Gómara, María J; García, María Luisa; Haro, Isabel

    2015-01-01

    In this work, a peptide for ocular delivery (POD) and human immunodeficiency virus transactivator were conjugated with biodegradable poly(lactic-co-glycolic acid) (PGLA)-polyethylene glycol (PEG)-nanoparticles (NPs) in an attempt to improve ocular drug bioavailability. The NPs were prepared by the solvent displacement method following two different pathways. One involved preparation of PLGA NPs followed by PEG and peptide conjugation (PLGA-NPs-PEG-peptide); the other involved self-assembly of PLGA-PEG and the PLGA-PEG-peptide copolymer followed by NP formulation. The conjugation of the PEG and the peptide was confirmed by a colorimetric test and proton nuclear magnetic resonance spectroscopy. Flurbiprofen was used as an example of an anti-inflammatory drug. The physicochemical properties of the resulting NPs (morphology, in vitro release, cell viability, and ocular tolerance) were studied. In vivo anti-inflammatory efficacy was assessed in rabbit eyes after topical instillation of sodium arachidonate. Of the formulations developed, the PLGA-PEG-POD NPs were the smaller particles and exhibited greater entrapment efficiency and more sustained release. The positive charge on the surface of these NPs, due to the conjugation with the positively charged peptide, facilitated penetration into the corneal epithelium, resulting in more effective prevention of ocular inflammation. The in vitro toxicity of the NPs developed was very low; no ocular irritation in vitro (hen's egg test-chorioallantoic membrane assay) or in vivo (Draize test) was detected. Taken together, these data demonstrate that PLGA-PEG-POD NPs are promising vehicles for ocular drug delivery.

  10. Conjugation of cell-penetrating peptides with poly(lactic-co-glycolic acid)-polyethylene glycol nanoparticles improves ocular drug delivery

    PubMed Central

    Vasconcelos, Aimee; Vega, Estefania; Pérez, Yolanda; Gómara, María J; García, María Luisa; Haro, Isabel

    2015-01-01

    In this work, a peptide for ocular delivery (POD) and human immunodeficiency virus transactivator were conjugated with biodegradable poly(lactic-co-glycolic acid) (PGLA)–polyethylene glycol (PEG)-nanoparticles (NPs) in an attempt to improve ocular drug bioavailability. The NPs were prepared by the solvent displacement method following two different pathways. One involved preparation of PLGA NPs followed by PEG and peptide conjugation (PLGA-NPs-PEG-peptide); the other involved self-assembly of PLGA-PEG and the PLGA-PEG-peptide copolymer followed by NP formulation. The conjugation of the PEG and the peptide was confirmed by a colorimetric test and proton nuclear magnetic resonance spectroscopy. Flurbiprofen was used as an example of an anti-inflammatory drug. The physicochemical properties of the resulting NPs (morphology, in vitro release, cell viability, and ocular tolerance) were studied. In vivo anti-inflammatory efficacy was assessed in rabbit eyes after topical instillation of sodium arachidonate. Of the formulations developed, the PLGA-PEG-POD NPs were the smaller particles and exhibited greater entrapment efficiency and more sustained release. The positive charge on the surface of these NPs, due to the conjugation with the positively charged peptide, facilitated penetration into the corneal epithelium, resulting in more effective prevention of ocular inflammation. The in vitro toxicity of the NPs developed was very low; no ocular irritation in vitro (hen’s egg test–chorioallantoic membrane assay) or in vivo (Draize test) was detected. Taken together, these data demonstrate that PLGA-PEG-POD NPs are promising vehicles for ocular drug delivery. PMID:25670897

  11. Regulation of the metastasis of murine ocular melanoma by natural killer cells.

    PubMed

    Harning, R; Koo, G C; Szalay, J

    1989-09-01

    In the current study we examine parameters affecting the metastasis of ocular tumors of in vivo derived B16F10 melanoma. In C57BL/6J beige (bg/bg) mice, with low NK activity, metastasis to the lungs was increased and survival time decreased. In C57BL/6J normal (+/+) mice treatment with PK136, a highly specific monoclonal anti-NK antibody (Ab), caused a depletion of NK cytotoxic activity, as demonstrated using a standard 51Cr release assay. In animals bearing ocular tumors, treatment with PK136 Ab resulted in significantly increased pulmonary metastasis and an altered pattern of metastasis. The effect of combined treatment protocols using LS2616 (linomide) and cyclophosphamide (Cy) was examined in enucleated and unenucleated animals. Treatment with LS2616 and Cy resulted in a significant decrease in mean pulmonary metastases (MPM), a decreased frequency of metastasis to the submandibular lymph nodes and an increase in mean survival time. In enucleated mice this combined treatment protocol resulted in apparent cures, the lowest MPM and the longest survival time observed. When tumor-bearing mice were treated with either silica, carrageenan or sublethal gamma irradiation, no effect on metastasis or survival was observed. This study demonstrates the importance of the NK cell as a primary effector cell for the control of metastasis from in vivo derived ocular B16F10 melanoma.

  12. Preservation of Ocular Epithelial Limbal Stem Cells: The New Frontier in Regenerative Medicine.

    PubMed

    Lužnik, Zala; Bertolin, Marina; Breda, Claudia; Ferrari, Barbara; Barbaro, Vanessa; Schollmayer, Petra; Ferrari, Stefano

    2016-01-01

    Significant advances have been made in the field of ocular regenerative medicine. Promising stem cell-based therapeutic strategies have been translated into the clinical practice over the last few decades. These new stem cell-based therapies offer the possibility of permanently restoring corneal epithelium in patients with severe disabling and blinding ocular surface disease. The European Union has already classified stem cell-based therapies as "medicinal products". Therefore, manipulation is strictly regulated according to the defined conditions of good manufacturing practice, with the production of stem cell therapeutics at only accredited production sites authorized by the national regulatory agencies. In this regard, as first medical products are licensed for commercial use in Europe enabling a more widespread access to a stem cell-based therapy, the need for safe, validated and reproducible techniques for ex vivo cultured tissue preservation and distribution are coming to the forefront of research. However, these provide various new challenges for biobanking industry such as the retention of viability, good functionality of stem cells and sterility issues. This chapter provides an overview of the current advances in the field of corneal/limbal epithelial stem cell culture preservation techniques using either hypothermic storage or cryopreservation methods, that were used in different culturing steps (from stem cell isolation to the ex vivo epithelial graft preparation), with the reported impact on the post-thawing product recovery.

  13. Autophagy in the Eye: Implications for Ocular Cell Health

    PubMed Central

    Frost, Laura S.; Mitchell, Claire H.; Boesze-Battaglia, Kathleen

    2014-01-01

    Autophagy, a catabolic process by which a cell “eats” itself, turning over its own cellular constituents, plays a key role in cellular homeostasis. In an effort to maintain normal cellular function, autophagy is often up-regulated in response to environmental stresses and excessive organelle damage to facilitate aggregated protein removal. In the eye, virtually all cell types from those comprising the cornea in the front of the eye to the retinal pigment epithelium (RPE) providing a protective barrier for the retina at the back of the eye, rely on one or more aspects of autophagy to maintain structure and/or normal physiological function. In the lens autophagy plays a critical role in lens fiber cell maturation and the formation of the organelle free zone. Numerous studies delineating the role of Atg5, Vsp34 as well as FYCO1 in maintenance of lens transparency are discussed. Corneal endothelial dystrophies are also characterized as having elevated levels of autophagic proteins. Therefore, novel modulators of autophagy such as lithium and melatonin are proposed as new therapeutic strategies for this group of dystrophies. In addition, we summarize how corneal Herpes Simplex Virus (HSV-1) infection subverts the cornea’s response to infection by inhibiting the normal autophagic response. Using glaucoma models we analyze the relative contribution of autophagy to cell death and cell survival. The cytoprotective role of autophagy is further discussed in an analysis of photoreceptor cell heath and function. We focus our analysis on the current understanding of autophagy in photoreceptor and RPE health, specifically on the diverse role of autophagy in rods and cones as well as its protective role in light induced degeneration. Lastly, in the RPE we highlight hybrid phagocytosis-autophagy pathways. This comprehensive review allows us to speculate on how alterations in various stages of autophagy contribute to glaucoma and retinal degenerations. PMID:24810222

  14. Ocular albinism type 1-induced melanoma cell migration is mediated through the RAS/RAF/MEK/ERK signaling pathway.

    PubMed

    Bai, Jun; Xie, Xin; Lei, Yun; An, Gaili; He, Li; Lv, Xiaopeng

    2014-07-01

    Malignant melanoma has the highest risk of mortality among all types of skin cancer due to its highly metastatic potential. The ocular albinism type 1 (OA1) protein is a pigment cell‑specific glycoprotein, which shares significant structural and functional features with G protein‑coupled receptors. However, the role of OA1 in melanoma has yet to be elucidated. The present study aimed to investigate whether OA1 is involved in melanoma cell migration. OA1 was found to stimulate cell migration in a dose‑dependent manner in cultured human melanoma cells. Furthermore, knockdown of OA1 using small interfering RNA was observed to significantly inhibit melanoma cell migration. In addition, the mechanism underlying OA1‑induced melanoma cell migration was investigated. Stimulation of the RAS/RAF/mitogen activated protein kinase kinase (MEK)/extracellular signal‑regulated kinase (ERK) pathway using growth factors enhanced OA1 expression and melanoma cell migration, whereas inhibition of this pathway using U0126 was observed to markedly decrease OA1 expression and the number of migrated cells. These findings indicate that OA1 is involved in melanoma cell migration and that OA1‑induced melanoma cell migration is mediated through the RAS/RAF/MEK/ERK signaling pathway. Therefore, OA1 may serve as a novel therapeutic target for melanoma.

  15. Ocular surface analysis in hematological patients before and after allogeneic hematopoietic stem cell transplantation: implication for daily clinical practice.

    PubMed

    Giannaccare, G; Bonifazi, F; Sessa, M; Dan, E; Arpinati, M; Fresina, M; Bandini, G; Cavo, M; Versura, P; Campos, E C

    2017-05-19

    PurposeTo evaluate ocular surface parameters before and after hematopoietic stem cell transplantation (HSCT) and to correlate them with clinical and transplant variables.MethodsThis is a retrospective analysis of data from 93 patients affected by hematological malignancies undergoing HSCT. Values from Ocular Surface Disease Index, Schirmer test, Break-up Time, ocular surface staining, and Meibomian Gland Dysfunction score obtained before HSCT and 3-6 months after were retrieved from charts. Diagnosis and staging of dry eye (DE) disease was performed according to Dry Eye WorkShop criteria. Graft-versus-host-disease (GVHD) was classified according to the NIH criteria. Odds ratios for DE onset after HSCT were estimated for demographic, ocular, hematological and transplant variables.ResultsDE was diagnosed before HSCT in 50 (53%) of the patients, mostly of hyperevaporative profile. After HSCT, all ocular parameters significantly worsened with no change in DE profile. A 51% incident cases (22 of the 43 non-DE subjects) were reported. Increasing recipient age and female sex, higher CD34+ cells infused, donor-recipient sex mismatch (males receiving from females), related donors, and peripheral blood cells as stem cell source were associated with a significant higher incidence of DE after HSCT. Systemic chronic GVHD was diagnosed in 42% while ocular GVHD in 35.5% of the patients, which decreased to 12% when taking into account only incident cases.ConclusionsHigh DE prevalence was shown already before HSCT. A pre-HSCT ocular surface assessment is recommended for early DE diagnosis and treatment. This new protocol also influences the prevalence of ocular GVHD.Eye advance online publication, 19 May 2017; doi:10.1038/eye.2017.78.

  16. [Use of stem cells cultured ex vivo for ocular surface reconstruction].

    PubMed

    Ricardo, José Reinaldo da Silva; Gomes, José Alvaro Pereira

    2010-01-01

    Lesions on the ocular surface can destroy the stem cells from the limbus and cause limbal stem cell deficiency. The limbal stem cell deficiency is marked by conjunctivalization, which can be defined as the invasion of conjunctival epithelium over the cornea. This process is accompanied by varying degrees of corneal changes such as neovascularization, inflammation, recurrent erosions, persistent epithelial defects, destruction of basement membrane of epithelium and stromal healing. Often, these changes are associated with poor visual acuity, photophobia and ocular discomfort. The best treatment for this disease is not known and varies in unilateral or bilateral cases. Among the treatments available, transplantation of limbal autograft or allograft is one of the most used. To improve the outcome of allotransplantation, some researchers use the transplantation of corneal epithelium cultured in the laboratory by ex vivo expansion of limbal stem cells, but due to limited availability of autologous tissue from the limbus and the risk of complications associated with immunosuppression in allogeneic tissue transplantation, researches of others options of stem cell cultured ex vivo have been described in experimental and clinical stage. This review describes the new types of stem cells cultured ex vivo, their current results and future potential.

  17. Conjunctival Squamous Cell Carcinoma due to Long-term Placement of Ocular Prosthesis

    PubMed Central

    Komoto, Masakazu; Matsumura, Takashi; Horiguchi, Masatoshi; Tanaka, Rica; Arakawa, Atsushi; Mizuno, Hiroshi

    2015-01-01

    Summary: Conjunctival squamous cell carcinoma (SCC) arising from an anophthalmic socket is quite rare, with few reports in the English literature. A 59-year-old man who had used an ocular prosthesis for 40 years had not removed the ocular prosthesis at all during the last 5 years. He had developed a mass on his entire right upper eyelid, and biopsy revealed a moderately differentiated SCC. Orbital exenteration including the upper and lower eyelid skin was performed. The defect was reconstructed with a free forearm flap followed by the placement of a facial epithesis. The pathology revealed an intraepithelial carcinoma on the upper palpebral conjunctiva, which seemed to infiltrate exclusively from that site to the upper eyelid and into the orbit. Other risk factors were not detected; therefore, chronic irritation or microtrauma of the upper conjunctiva from the prosthesis due to persistent prosthesis placement could have been the main trigger for the development of SCC. In cases where the ocular prosthesis is not fitted properly or removed appropriately, clinicians should be aware of this possible long-term consequence. PMID:25878936

  18. [The cell phones as devices for the ocular fundus documentation].

    PubMed

    Němčanský, J; Kopecký, A; Timkovič, J; Mašek, P

    2014-12-01

    To present our experience with "smart phones" when examining and documenting human eyes. From September to October 2013 fifteen patients (8 men, 7 women) eye fundus was examined, an average age during the examination was 58 year (ranging from 20-65 years). The photo-documentation was performed with dilated pupils (tropicamid hydrochloridum 1% eye drops) with mobile phone Samsung Galaxy Nexus with the operating system Android 4.3 (Google Inc., Mountain View, CA, USA) and iPhone 4 with the operating system 7.0.4 (Apple Inc., Loop Cupertino, CA, USA), and with 20D lens (Volk Optical Inc., Mentor, OH, USA). The images of the retina taken with a mobile phone and the spherical lens are of a very good quality, precise and reproducible. Learning this technique is easy and fast, the learning curve is steep. Photo-documentation of retina with a mobile phone is a safe, time-saving, easy-to-learn technique, which may be used in a routine ophthalmologic practice. The main advantage of this technique is availability, small size and easy portability of the devices.

  19. The Visual System of Zebrafish and its Use to Model Human Ocular Diseases

    PubMed Central

    Gestri, Gaia; Link, Brian A; Neuhauss, Stephan CF

    2011-01-01

    Free swimming zebrafish larvae depend mainly on their sense of vision to evade predation and to catch prey. Hence there is strong selective pressure on the fast maturation of visual function and indeed the visual system already supports a number of visually-driven behaviors in the newly hatched larvae. The ability to exploit the genetic and embryonic accessibility of the zebrafish in combination with a behavioral assessment of visual system function has made the zebrafish a popular model to study vision and its diseases. Here, we review the anatomy, physiology and development of the zebrafish eye as the basis to relate the contributions of the zebrafish to our understanding of human ocular diseases. PMID:21595048

  20. Age-related changes in human vestibulo-ocular and optokinetic reflexes: Pseudorandom rotation tests

    NASA Technical Reports Server (NTRS)

    Peterka, R. J.; Black, F. O.; Schoenhoff, M. B.

    1989-01-01

    The dynamic response properties of horizontal vestibulo-ocular reflex (VOR) and optokinetic reflex (OKR) were characterized in 216 human subjects ranging in age from 7 to 81 years. The object of this cross-sectional study was to determine the effects of aging on VOR and OKR reflex dynamics, and to identify the distributions of parameters which describe VOR and OKR responses to pseudorandom stimuli in a putatively normal population. In general, VOR and OKR response parameters changed in a manner consistent with declining function with increasing age. For the VOR this was reflected in declining response amplitudes, although the magnitude of the decline was small relative to the variability of the data. For the OKR the lag time of the response, probably associated with the time required for visual information processing, increased linearly with age at a rate of about 1 ms per year.

  1. Ocular and generalized myasthenia gravis induced by human acetylcholine receptor γ subunit immunization.

    PubMed

    Wu, Xiaorong; Tuzun, Erdem; Li, Jing; Xiao, Tianlin; Saini, Shamsher S; Qi, Huibin; Allman, Windy; Christadoss, Premkumar

    2012-02-01

    HLA-DQ8 transgenic mice develop ocular myasthenia gravis (oMG), which then progresses to generalized MG (gMG) when immunized with the human acetylcholine receptor (H-AChR) α subunit. Because the fetal AChR γ subunit is expressed in adult extraocular muscles, we anticipated that γ subunit immunization would generate an immune response to mouse AChR and induce MG in mice. H-AChR γ subunit immunization in HLA-DQ8 mice induced an autoimmune response to mouse AChR and led to the destruction of AChR in the neuromuscular junction (NMJ) by anti-AChR antibody and complement activation, and it triggered upregulation of AChR gene transcription. Our findings indicate that oMG may be induced by immunity to the AChR γ subunit. Copyright © 2011 Wiley Periodicals, Inc.

  2. Induced pluripotent stem cell-derived limbal epithelial cells (LiPSC) as a cellular alternative for in vitro ocular toxicity testing.

    PubMed

    Aberdam, Edith; Petit, Isabelle; Sangari, Linda; Aberdam, Daniel

    2017-01-01

    Induced pluripotent stem cells hold great potential to produce unlimited amount of differentiated cells as cellular source for regenerative medicine but also for in vitro drug screening and cytotoxicity tests. Ocular toxicity testing is mandatory to evaluate the risks of drugs and cosmetic products before their application to human patients by preventing eye irritation or insult. Since the global ban to use animals, many human-derived alternatives have been proposed, from ex-vivo enucleated postmortem cornea, primary corneal cell culture and immortalized corneal epithelial cell lines. All of them share limitations for their routine use. Using an improved protocol, we derived limbal epithelial cells from human induced pluripotent stem cells, named LiPSC, that are able to be passaged and differentiate further into corneal epithelial cells. Comparative RT-qPCR, immunofluorescence staining, flow cytometry analysis and zymography assays demonstrate that LiPSC are morphologically and molecularly similar to the adult stem cells. Moreover, contrary to HCE, LiPSC and primary limbal cells display similarly sensitive to cytotoxicity treatment among passages. Our data strongly suggest that LiPSC could become a powerful alternative cellular model for cosmetic and drug tests.

  3. Bilateral ocular panadnexal mass as initial presentation of systemic blastoid variant of mantle-cell lymphoma.

    PubMed

    Rašić, Dejan M; Knežević, Miroslav; Terzić, Tatjana; Vlajković, Gordana

    A 66-year-old man developed a slowly enlarging, bilateral, painless, periorbital, and orbital swelling with ptosis, nonaxial proptosis, chemosis, exposure keratopathy, and decreased vision in both eyes. He had fever, night sweats, and weight loss (B-symptoms), along with lymphadenopathy and elevated serum lactate dehydrogenase, with no prior history of lymphoma. A transpalpebral incisional biopsy revealed a rare case of mantle-cell lymphoma of blastoid variant, stage IVB. The main immunophenotype characteristics were cyclin D1+, CD5+, CD10-, CD23-, Bcl-6-/+, and a high (up to 80%) Ki-67 proliferation index. Following an excellent response to the immune-chemotherapy treatment plan, all ocular adnexal lymphoma manifestations disappeared completely; however, 13 months after the initial presentation, there was a recurrence of the disease with rapid worsening and death. The blastoid variant of mantle cell lymphoma, a rare subtype of mantle-cell lymphoma, is a highly aggressive neoplasm, ultimately having a fatal outcome. As the initial manifestation of the disease, ocular adnexal region blastoid variant of mantle-cell lymphoma is an exceptional event, with only one previous case reported.

  4. Ocular Distribution, Spectrum of Activity, and In Vivo Viral Neutralization of a Fully Humanized Anti-Herpes Simplex Virus IgG Fab Fragment following Topical Application

    PubMed Central

    Berdugo, Marianne; Larsen, Inna V.; Abadie, Claire; Deloche, Catherine; Kowalczuk, Laura; Touchard, Elodie; Dubielzig, Richard; Brandt, Curtis R.; Combette, Jean-Marc

    2012-01-01

    Herpes simplex ocular infection is a major cause of corneal blindness. Local antiviral treatments exist but are associated with corneal toxicity, and resistance has become an issue. We evaluated the biodistribution and efficacy of a humanized anti-herpes simplex virus (anti-HSV) IgG FAb fragment (AC-8; 53 kDa) following repeated topical administration. AC-8 was found in the corneal epithelium, anterior stroma, subepithelial stromal cells, and retinal glial cells, with preferential entry through the ocular limbus. AC-8 was active against 13 different strains of HSV-1, with 50% and 90% mean effective concentrations (MEC50 and MEC90, respectively) ranging from 0.03 to 0.13 μg/ml, indicating broad-spectrum activity. The in vivo efficacy of AC-8 was evaluated in a mouse model of herpes-induced ocular disease. Treatment with low-dose AC-8 (1 mg/ml) slightly reduced the ocular disease scores. A greater reduction of the disease scores was observed in the 10-mg/ml AC-8-treated group, but not as much as with trifluridine (TFT). AC-8 treatment reduced viral titers but less than trifluridine. AC-8 did not display any toxicity to the cornea or other structures in the eye. In summary, topical instillation of an anti-HSV FAb can be used on both intact and ulcerated corneas. It is well tolerated and does not alter reepithelialization. Further studies to improve the antiviral effect are needed for AC-8 to be considered for therapeutic use. PMID:22203590

  5. Human Ocular Infection with Dirofilaria repens (Railliet and Henry, 1911) in an Area Endemic for Canine Dirofilariasis

    PubMed Central

    Otranto, Domenico; Brianti, Emanuele; Gaglio, Gabriella; Dantas-Torres, Filipe; Azzaro, Salvatore; Giannetto, Salvatore

    2011-01-01

    Dirofilaria repens, which is usually found in canine subcutaneous tissues, is the main causative agent of human dirofilariasis in the Old Word. However, a relationship between animal and human cases of dirofilariasis caused by D. repens in a given area has never been demonstrated. The uneven distribution of D. repens in provinces in Sicily, Italy represented the foundation for this study. We report a human case of ocular infection with D. repens from Trapani Province, where canine dirofilariasis is endemic. The nematode was morphologically and molecularly identified and surgical removal of the parasite was documented. The relationship between the prevalence of D. repens in dogs and the occurrence of human cases of ocular dirofilariasis is discussed on the basis of a review of the historical literature. PMID:21633041

  6. Olfactomedin-like 3 (OLFML3) gene expression in baboon and human ocular tissues: cornea, lens, uvea and retina

    PubMed Central

    Rodríguez-Sánchez, Iràm Pablo; Garza-Rodríguez, Maria Lourdes; Mohamed-Noriega, Karim; Voruganti, Venkata Saroja; Tejero, Maria Elizabeth; Delgado-Enciso, Ivan; Ibave, Diana Cristina Perez; Schlabritz-Loutsevitch, Natalia E.; Mohamed-Noriega, Jibran; Martinez-Fierro, Margarita L; Reséndez-Pérez, Diana; Cole, Shelley A; Cavazos-Adame, Humberto; Comuzzie, Anthony G.; Mohamed-Hamsho, Jesús; Barrera-Saldaña, Hugo Alberto

    2013-01-01

    Background Olfactomedin-like is a polyfunctional polymeric glycoprotein. This family has at least four members. One member of this family is OLFML3, which is preferentially expressed in placenta but is also detected in other adult tissues including the liver and heart. However, the orthologous rat gene is expressed in the iris, sclera, trabecular meshwork, retina, and optic nerve. Methods OLFML3 amplification was performed by RT-PCR from human and baboon ocular tissues. The products were cloned and sequenced. Results We report OFML3 expression in human and baboon eye. The full CDS has 1221 bp, from which a OFR of 406 amino acid was obtained. The baboon OLFML3 gene nucleotidic sequence has 98%, and amino acidic 99% similarity with humans. Conclusions OLFML3 expression in human and baboon ocular tissues and its high similarity make the baboon a powerful model to deduce the physiological and/or metabolic function of this protein in the eye. PMID:23398349

  7. Ocular adnexal marginal zone B cell lymphoma: a clinical and pathologic study of 23 cases.

    PubMed

    Charlotte, Frédéric; Doghmi, Kamal; Cassoux, Nathalie; Ye, Hongtao; Du, Ming-Qing; Kujas, Michèle; Lesot, Annette; Mansour, George; Lehoang, Phuc; Vignot, Nicole; Capron, Frédérique; Leblond, Véronique

    2006-04-01

    To better characterize ocular adnexal marginal zone lymphoma of mucosa-associated lymphoid tissue (MZL-MALT), we analyzed the clinical and pathologic features of 23 patients (11 men, 12 women, median age 66 years). The tumor was confined to one ocular structure in 18 cases (conjunctiva, n=8; orbit, n=8; or lacrimal gland, n=2). Concurrent extraorbital disease was detected by the staging procedure in five patients, and preferentially involved other MALT sites. Histogenetic B cell marker studies, available in 13 cases, showed an early post-germinal center (GC) phenotype (BCL-6(-)/IRF4(+)/CD138(-)) (n=5) or a late post-GC phenotype (BCL-6(-)/IRF4(+)/CD138(+)) (n=8), which could be helpful for discrimination from other types of small-B cell lymphoma. BCL10 was positive in 12 of 13 patients tested, with nuclear (n=4) or cytoplasmic (n=8) immunoreactivity. These staining patterns ruled out t(1;14)(p22;q32) translocation. T(11;18)(q21;q21), another MZL-MALT-specific translocation, was detected by reverse transcriptase polymerase chain reaction in four of 15 patients tested. Clinical outcome was excellent but the overall relapse rate was 26.1% with a median follow-up of 39 months (range 6-132 months). Regardless of the disease stage at diagnosis, combined chemotherapy and radiotherapy seemed to be more effective than chemotherapy alone in ocular adnexal MZL-MALT, as persistent complete remission was achieved in nine patients receiving combination therapy, while six of 14 patients treated with chemotherapy alone relapsed.

  8. Retention of reversibly thermo-gelling timolol on the human ocular surface studied by video meniscometry.

    PubMed

    Ishibashi, Takeshi; Yokoi, Norihiko; Bron, Anthony J; Tiffany, John M; Komuro, Aoi; Kinoshita, Shigeru

    2003-08-01

    To investigate the retention of reversibly thermo-gelling timolol (TG-timolol) on the human ocular surface using video meniscometry. The study population consisted of 14 healthy volunteers with no external eye disease. Fifteen microl TG-timolol were instilled into one eye of each subject and the same volume of aqueous, timolol ophthalmic solution was instilled in the fellow eye, in a masked fashion. Tear meniscus curvature was monitored at the center of the lower meniscus in each eye, using a newly-developed video meniscometer, before and at one-minute intervals for ten minutes after, the instillation. The radius of meniscus curvature (R) was calculated from printed video-images using the concave mirror formula. The change in R with time after instillation was compared for the two groups. The change in meniscus radius with time t [defined as deltaR(t) = R(t) - R(0)] showed a significant exponential regression in both the TG-timolol and the timolol groups. There was a significant difference in the value of deltaR(5) and deltaR(10) between eyes with TG-timolol [deltaR(5) = 0.29 mm, deltaR(10) = 0.18mm] and eyes with timolol only [deltaR(5) = 0.10mm, deltaR(10) = 0.06 mm] [deltaR(5): P < 0.001, deltaR(10): P < 0.001]. The area under each regression curve of deltaR(t), an indicator of vehicle retention, was greater in the eyes treated with TG-timolol than in those receiving timolol only (2.09 vs. 0.56, P < 0.001). The present study demonstrated that the reversibly thermo-gelling timolol was better retained at the ocular surface than conventional, aqueous timolol.

  9. Human ocular following initiated by competing image motions: evidence for a winner-take-all mechanism.

    PubMed

    Sheliga, B M; Kodaka, Y; FitzGibbon, E J; Miles, F A

    2006-06-01

    The initial ocular following responses (OFRs) elicited by 1/4-wavelength steps applied to the missing fundamental (mf) stimulus are in the backward direction and largely determined by the principal Fourier component, the 3rd harmonic [Sheliga, B. M., Chen, K. J., FitzGibbon, E. J., & Miles, F. A. (2005). Initial ocular following in humans: A response to first-order motion energy. Vision Research, 45, 3307-3321]. When the contrast of the 3rd harmonic was selectively reduced below that of the next most prominent harmonic-the 5th, which moves in the opposite (forward) direction-then the OFR reversed direction and the 3rd harmonic effectively lost all of its influence as the OFR was now largely determined by the 5th harmonic. Restricting the stimulus to just two sine waves (of equal efficacy when of equal contrast and presented singly) with the spatial frequencies of the 3rd and 5th harmonics of the mf stimulus indicated that the critical factor was the ratio of their two contrasts: when of similar contrast both were effective (vector sum/averaging), but when the contrast of one was <1/2 that of the other then the one with the lower contrast became ineffective (winner-take-all). This nonlinear dependence on the contrast ratio was attributed to mutual inhibition and was well described by a weighted-average model with just two free parameters. Further experiments with broadband and dual-grating stimuli indicated that nonlinear interactions occur not only in the neural processing of stimuli moving in opposite directions but also of stimuli that share the same direction and differ only in their spatial frequency and speed. Clearly, broad-band and dual-grating stimuli can uncover significant nonlinearities in visual information processing that are not evident with single sine-wave stimuli.

  10. Kinematics of Vertical Saccades during the Yaw Vestibulo-ocular Reflex in Humans

    PubMed Central

    Crane, Benjamin T.; Tian, Junru; Demer, Joseph L.

    2007-01-01

    Purpose Listing’s law (LL) constrains the rotational axes of saccades and pursuit eye movements to Listing’s plane (LP). In the velocity domain, LL is ordinarily equivalent to a tilt in the ocular velocity axis equal to half the change in eye position, giving a tilt angle ratio (TAR) of 0.5. This study was undertaken to investigate vertical saccade behavior after the yaw vestibulo-ocular reflex (VOR) had driven eye torsion out of LP, an initial condition causing the position and velocity domain formulations of LL to differ. Methods Binocular eye and head motions were recorded with magnetic search coils in eight humans. With the head immobile, LP was determined for each eye, and mean TAR was 0.50 ± 0.07 (mean ± SD) for horizontal and 0.45 ± 0.11 for vertical saccades. The VOR was evoked by transient, whole-body yaw at 2800 deg/s2 peak acceleration, capable of evoking large, uninterrupted VOR slow phases. Before rotation, subjects viewed a target at eye level, 20° up, or 20° down. In two thirds of the trials, the target moved upward or downward at systematically varying times, triggering a vertical saccade during the horizontal VOR slow phase. Results Because the head rotation axis was generally misaligned with LP, the eye averaged 3.6° out of LP at vertical saccade onset. During the saccade, eye position continued to depart LP by an average 0.8°. The horizontal TAR at saccade onset was 0.29 ± 0.07. At peak saccade velocity 35 ± 3 ms later, the vertical TAR was 0.45 ± 0.07, statistically similar to that of head fixed saccades. Saccades did not return to LP. Conclusions Although they did not observe the position domain formulation of LL, vertical saccades, during the VOR, observed the half-angle velocity domain formulation of LL. PMID:16043853

  11. Ultrasound and photoacoustic imaging to monitor ocular stem cell delivery and tissue regeneration (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Kubelick, Kelsey; Snider, Eric; Yoon, Heechul; Ethier, C. Ross; Emelianov, Stanislav Y.

    2017-03-01

    Glaucoma is associated with dysfunction of the trabecular meshwork (TM), a fluid drainage tissue in the anterior eye. A promising treatment involves delivery of stem cells to the TM to restore tissue function. Currently histology is the gold standard for tracking stem cell delivery and differentiation. To expedite clinical translation, non-invasive longitudinal monitoring in vivo is desired. Our current research explores a technique combining ultrasound (US) and photoacoustic (PA) imaging to track mesenchymal stem cells (MSCs) after intraocular injection. Adipose-derived MSCs were incubated with gold nanospheres to label cells (AuNS-MSCs) for PA imaging. Successful labeling was first verified with in vitro phantom studies. Next, MSC delivery was imaged ex vivo in porcine eyes, while intraocular pressure was hydrostatically clamped to maintain a physiological flow rate through the TM. US/PA imaging was performed before, during, and after AuNS-MSC delivery. Additionally, spectroscopic PA imaging was implemented to isolate PA signals from AuNS-MSCs. In vitro cell imaging showed AuNS-MSCs produce strong PA signals, suggesting that MSCs can be tracked using PA imaging. While the cornea, sclera, iris, and TM region can be visualized with US imaging, pigmented tissues also produce PA signals. Both modalities provide valuable anatomical landmarks for MSC localization. During delivery, PA imaging can visualize AuNS-MSC motion and location, creating a unique opportunity to guide ocular cell delivery. Lastly, distinct spectral signatures of AuNS-MSCs allow unmixing, with potential for quantitative PA imaging. In conclusion, results show proof-of-concept for monitoring MSC ocular delivery, raising opportunities for in vivo image-guided cell delivery.

  12. Ocular Hypotensive Effects of the ATP-Sensitive Potassium Channel Opener Cromakalim in Human and Murine Experimental Model Systems

    PubMed Central

    Roy Chowdhury, Uttio; Bahler, Cindy K.; Holman, Bradley H.; Dosa, Peter I.; Fautsch, Michael P.

    2015-01-01

    Elevated intraocular pressure (IOP) is the most prevalent and only treatable risk factor for glaucoma, a leading cause of irreversible blindness worldwide. Unfortunately, all current therapeutics used to treat elevated IOP and glaucoma have significant and sometimes irreversible side effects necessitating the development of novel compounds. We evaluated the IOP lowering ability of the broad spectrum KATP channel opener cromakalim. Cultured human anterior segments when treated with 2 μM cromakalim showed a decrease in pressure (19.33 ± 2.78 mmHg at 0 hours to 13.22 ± 2.64 mmHg at 24 hours; p<0.001) when compared to vehicle treated controls (15.89 ± 5.33 mmHg at 0 h to 15.56 ± 4.88 mmHg at 24 hours; p = 0.89). In wild-type C57BL/6 mice, cromakalim reduced IOP by 18.75 ± 2.22% compared to vehicle treated contralateral eyes (17.01 ± 0.32 mmHg at 0 hours to 13.82 ± 0.37 mmHg at 24 hours; n = 10, p = 0.002). Cromakalim demonstrated an additive effect when used in conjunction with latanoprost free acid, a common ocular hypotensive drug prescribed to patients with elevated IOP. To examine KATP channel subunit specificity, Kir6.2(-/-) mice were treated with cromakalim, but unlike wild-type animals, no change in IOP was noted. Histologic analysis of treated and control eyes in cultured human anterior segments and in mice showed similar cell numbers and extracellular matrix integrity within the trabecular meshwork, with no disruptions in the inner and outer walls of Schlemm’s canal. Together, these studies suggest that cromakalim is a potent ocular hypotensive agent that lowers IOP via activation of Kir6.2 containing KATP channels, its effect is additive when used in combination with the commonly used glaucoma drug latanoprost, and is not toxic to cells and tissues of the aqueous humor outflow pathway, making it a candidate for future therapeutic development. PMID:26535899

  13. Effective Melanin Depigmentation of Human and Murine Ocular Tissues: An Improved Method for Paraffin and Frozen Sections

    PubMed Central

    Manicam, Caroline; Pitz, Susanne; Brochhausen, Christoph; Grus, Franz H.; Pfeiffer, Norbert; Gericke, Adrian

    2014-01-01

    Purpose The removal of excessive melanin pigments that obscure ocular tissue morphology is important to address scientific questions and for differential diagnosis of ocular tumours based on histology. Thus, the goal of the present study was to establish an effective and fast melanin bleaching method for paraffin and frozen mouse and human ocular tissues. Methods Paraffin-embedded and frozen ocular specimens from mice and human donors were subjected to bleaching employing two methods. The first employed potassium permanganate (KMnO4) with oxalic acid, and the second 10% hydrogen peroxide (H2O2). To determine optimal bleaching conditions, depigmentation was carried out at various incubation times. The effect of diluents used for 10% H2O2 was assessed using phosphate-buffered saline (PBS), and deionized water. Three different slide types and two fixatives, which were ice-cold acetone with 80% methanol, and 4% paraformaldehyde (PFA) were used to determine the optimal conditions for better tissue adherence during bleaching. All tissues were stained in hematoxylin and eosin for histological evaluation. Results Optimal bleaching was achieved using warm 10% H2O2 diluted in PBS at 65°C for 120 minutes. Chromium-gelatin-coated slides prevented tissue detachment. Adherence of cryosections was also improved with post-fixation using 4% PFA and overnight air-drying at RT after cryosectioning. Tissue morphology was preserved under these conditions. Conversely, tissues bleached in KMnO4/oxalic acid demonstrated poor depigmentation with extensive tissue damage. Conclusions Warm dilute H2O2 at 65°C for 120 minutes rapidly and effectively bleached both cryo- and paraffin sections of murine and human ocular tissues. PMID:25025426

  14. Effective melanin depigmentation of human and murine ocular tissues: an improved method for paraffin and frozen sections.

    PubMed

    Manicam, Caroline; Pitz, Susanne; Brochhausen, Christoph; Grus, Franz H; Pfeiffer, Norbert; Gericke, Adrian

    2014-01-01

    The removal of excessive melanin pigments that obscure ocular tissue morphology is important to address scientific questions and for differential diagnosis of ocular tumours based on histology. Thus, the goal of the present study was to establish an effective and fast melanin bleaching method for paraffin and frozen mouse and human ocular tissues. Paraffin-embedded and frozen ocular specimens from mice and human donors were subjected to bleaching employing two methods. The first employed potassium permanganate (KMnO4) with oxalic acid, and the second 10% hydrogen peroxide (H2O2). To determine optimal bleaching conditions, depigmentation was carried out at various incubation times. The effect of diluents used for 10% H2O2 was assessed using phosphate-buffered saline (PBS), and deionized water. Three different slide types and two fixatives, which were ice-cold acetone with 80% methanol, and 4% paraformaldehyde (PFA) were used to determine the optimal conditions for better tissue adherence during bleaching. All tissues were stained in hematoxylin and eosin for histological evaluation. Optimal bleaching was achieved using warm 10% H2O2 diluted in PBS at 65°C for 120 minutes. Chromium-gelatin-coated slides prevented tissue detachment. Adherence of cryosections was also improved with post-fixation using 4% PFA and overnight air-drying at RT after cryosectioning. Tissue morphology was preserved under these conditions. Conversely, tissues bleached in KMnO4/oxalic acid demonstrated poor depigmentation with extensive tissue damage. Warm dilute H2O2 at 65°C for 120 minutes rapidly and effectively bleached both cryo- and paraffin sections of murine and human ocular tissues.

  15. Ocular manifestations in egyptian children and young adults with sickle cell disease.

    PubMed

    El-Ghamrawy, Mona Kamal; El Behairy, Hanan F; El Menshawy, Amal; Awad, Seham A; Ismail, Ahmed; Gabal, Mohamed Salah

    2014-12-01

    In sickle cell disease (SCD), ocular lesions result from stasis and occlusion of small eye vessels by sickled erythrocytes. Vaso-occlusive disease of the retina can be responsible for nonproliferative (NPR) and proliferative retinopathy (PR). Patients are often asymptomatic until serious complications arise as, vitreous hemorrhage and retinal detachment. This work aimed to study the frequency and pattern of ocular manifestations in Egyptian children and young adults with SCD. In this cross-sectional study, 40 steady state patients (80 eyes) aged 2-28 years (30 children and 10 young adults) with established diagnosis of SCD (26 with homozygous SS and 14 with S/β thalassemia underwent complete ophthalmic examination with dilated fundoscopy. Fluorescein angiography was performed for patients ≥12 years old. The overall frequency of retinal lesions was 47.5 % (46.2 and 50 % of SS and S/β patients respectively). PR and NPR were evident in 32.5 and 27.5 % of all enrolled patients respectively (five patients having both). Peripheral retinal occlusion was a frequent ocular finding in both groups; the youngest patient showing PR was 15 years old. Older age, longer disease duration and splenectomy were significantly more prevalent among patients with PR. Despite lack of visual symptoms, children and young adults are at risk of PR. Frequency of retinal lesions was comparable in SS and S/β patients. Periodic ophthalmologic examination starting at the age of 12 years is recommended for timely-identification of retinal lesions thus minimizing the risk of sight threatening retinopathy.

  16. Formation of Segmental Rounded Nodules During Infiltration of Adult T-Cell Leukemia Cells Into the Ocular Mucous Membrane.

    PubMed

    Kamoi, Koju; Nagata, Yoichi; Mochizuki, Manabu; Kobayashi, Daisuke; Ohno, Nobuhiro; Uchimaru, Kaoru; Tojo, Arinobu; Ohno-Matsui, Kyoko

    2016-01-01

    To document a case of adult T-cell leukemia (ATL) cell infiltration into the ocular mucous membrane that presented with rounded nodule formation. Observational case report. A 36-year-old woman presented with bilateral conjunctival hyperemia and small papules on the legs and face. After complaining of significant fatigue at 6 months, she was diagnosed with high-risk chronic-type ATL. Ophthalmic examination revealed the formation of bilateral segmental rounded nodules, which were located both at the bulbar conjunctiva around the corneal limbus and at the palpebral conjunctiva around each lacrimal punctum. Although cellular infiltrations were also seen at the corneal subepithelium and stroma, no cellular infiltrations were observed in the anterior chamber, vitreous, or retina. Biopsy was performed of the bulbar and palpebral conjunctiva, and the polymerase chain reaction detected HTLV-1 proviral DNA and monoclonal T-cell receptor γ-chain gene rearrangement in both samples. Pathological evaluations identified atypical lymphoid cells that were consistent with ATL cells. These analyses confirmed that the rounded nodules were formed in conjunction with the infiltration of ATL cells. The formation of multiple rounded nodules during ATL cell infiltration into the ocular mucous membrane, especially at the palpebral conjunctiva around the lacrimal punctum, may be a distinguishing feature of ATL.

  17. Infrared imaging of sub-retinal structures in the human ocular fundus.

    PubMed

    Elsner, A E; Burns, S A; Weiter, J J; Delori, F C

    1996-01-01

    The interaction of infrared light with the human ocular fundus, particularly sub-retinal structures, was studied in vivo. Visible and infra-red wavelengths and a scanning laser ophthalmoscope were used to acquire digital images of the human fundus. The contrast and reflectance of selected retinal and sub-retinal features were computed for a series of wavelengths or modes of imaging. Near infrared light provides better visibility than visible light for sub-retinal features. Sub-retinal deposits appear light and thickened; the optic nerve head, retinal vessels, and choroidal vessels appear dark. Contrast and visibility of features increases with increasing wavelength from 795 to 895 nm. Optimizing the mode of imaging improves the visibility of some structures. This new quantitative basis for near infrared imaging techniques can be applied to a wide range of imaging modalities for the study of pathophysiology and treatment in diseases affecting the retinal pigment epithelium and Bruch's membrane, such as age-related macular degeneration.

  18. Cell viability score (CVS) as a good indicator of critical concentration of benzalkonium chloride for toxicity in cultured ocular surface cell lines.

    PubMed

    Iwasawa, Atsuo; Ayaki, Masahiko; Niwano, Yoshimi

    2013-07-01

    Cytotoxicity of benzalkonium chloride (BAK) is a major factor affecting drug cytotoxicity. This study aimed to determine the critical concentration of BAK for cultured ocular cells, using SIRC (rabbit corneal epithelium), BCE C/D-1b (bovine corneal epithelial cells), RC-1 (rabbit corneal epithelium), and Chang (human conjunctival cells). Cell viability was determined following the exposure of cells to 11 concentrations of BAK for 10, 30, or 60 min using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and neutral red assays, and the cell viability score (CVS) was used to evaluate comprehensively the toxicity of BAK. The CVS system consists of two values. The CVS50 was determined by the number of measurements for viability ≥50% of control. The CVS40/80 was calculated as follows: CVS40/80=(number of measurements for viability values >80%)-(number of measurements for viability values <40%). Both %CVS50 and %CVS40/80 decreased with concentrations of BAK. When BAK concentrations were 0.01% or higher, %CVS50 and %CVS40/80 became 0 and less than -90, respectively. Meanwhile, when BAK concentrations were 0.001% or lower, %CVS50 became 100. In the case of %CVS40/80, when the BAK concentrations were 0.002% or lower, the values reached 75 or more, and when 0.0005% or lower, the %CVS40/80 value reached 100. Accordingly, BAK induced very low cytotoxicity in the cultured ocular cell lines at concentrations of 0.002% or lower. The concentration-dependency confirmed that the CVS score is useful for expressing drug cytotoxicity in a simple and comprehensive manner.

  19. Amniotic membrane traps and induces apoptosis of inflammatory cells in ocular surface chemical burn

    PubMed Central

    Liu, Ting; Zhai, Hualei; Xu, Yuanyuan; Dong, Yanling; Sun, Yajie; Zang, Xinjie

    2012-01-01

    Purpose Severe chemical burns can cause necrosis of ocular surface tissues following the infiltration of inflammatory cells. It has been shown that amniotic membrane transplantation (AMT) is an effective treatment for severe chemical burns, but the phenotypes of cells that infiltrate the amniotic membrane and the clinical significance of these cellular infiltrations have not previously been reported. The present work studies the inflammation cell traps and apoptosis inducing roles of the amniotic membrane after AMT in patients with acute chemical burns. Methods A total of 30 patients with acute alkaline burns were classified as having either moderate or severe burns. In all participants, AMT was performed within one week of his/her injury. After 7–9 days, the transplanted amniotic membranes were removed. Histopathological and immunohistochemical techniques were used for the examination and detection of infiltrating cells, and tests for the expression of CD (cluster of differentiation)15, CD68, CD3, CD20, CD57, CD31, CD147, and CD95 (Fas) were performed. A TUNEL (TdT-mediated dUTP nick end labeling) assay was used to confirm apoptosis of the infiltrating cells. Three patients with herpes simplex-induced keratitis who had undergone AMT to treat persistent epithelium defects were used as a control group. Amniotic membrane before transplantation was used as another control. Results After amniotic membrane transplantation, the number of infiltrating cells in patients with severe burns was significantly higher than in patients with moderate burns or in control patients (p<0.05). Among the severe burns patients, CD15 and CD68 were widely expressed in the infiltrating cells, and CD3, CD20, and CD57 were only found in a small number of cells. Occasionally, CD31-positive cells were found in the amniotic membranes. More cells that were CD147, Fas, and TUNEL positive were found in patients with severe burns than in patients with moderate burns or in control patients

  20. Muller glia, vision-guided ocular growth, retinal stem cells, and a little serendipity: the Cogan lecture.

    PubMed

    Fischer, Andy J

    2011-09-29

    Hypothesis-driven science is expected to result in a continuum of studies and findings along a discrete path. By comparison, serendipity can lead to new directions that branch into different paths. Herein, I describe a diverse series of findings that were motivated by hypotheses, but driven by serendipity. I summarize how investigations into vision-guided ocular growth in the chick eye led to the identification of glucagonergic amacrine cells as key regulators of ocular elongation. Studies designed to assess the impact of the ablation of different types of neurons on vision-guided ocular growth led to the finding of numerous proliferating cells within damaged retinas. These proliferating cells were Müller glia-derived retinal progenitors with a capacity to produce new neurons. Studies designed to investigate Müller glia-derived progenitors led to the identification of a domain of neural stem cells that form a circumferential marginal zone (CMZ) that lines the periphery of the retina. Accelerated ocular growth, caused by visual deprivation, stimulated the proliferation of CMZ progenitors. We formulated a hypothesis that growth-regulating glucagonergic cells may regulate both overall eye size (scleral growth) and the growth of the retina (proliferation of CMZ cells). Subsequent studies identified unusual types of glucagonergic neurons with terminals that ramify within the CMZ; these cells use visual cues to control equatorial ocular growth and the proliferation of CMZ cells. Finally, while studying the signaling pathways that stimulate CMZ and Müller glia-derived progenitors, serendipity led to the discovery of a novel type of glial cell that is scattered across the inner retinal layers.

  1. Effects of dynamic exercise and its intensity on ocular blood flow in humans.

    PubMed

    Hayashi, Naoyuki; Ikemura, Tsukasa; Someya, Nami

    2011-10-01

    Visual performance is impaired when the ocular blood flow decreases, indicating that ocular blood flow plays a role in maintaining visual performance during exercise. We examined the ocular blood flow response to incremental cycling exercise to test the hypothesis that ocular blood flow is relatively stable during dynamic exercise because of its autoregulatory nature. The blood flow in the inferior and superior temporal retinal arterioles (ITRA and STRA, respectively) and retinal and choroidal vessels (RCV), mean arterial pressure, and heart rate (HR) were measured at rest and during leg cycling in nine young and healthy subjects (26 ± 5 years, mean ± SD). Ocular blood flow was measured by laser speckle flowmetry. The exercise intensity was incremented by 30 W every 3 min until the subject was unable to maintain a position appropriate for measuring ocular blood flow. Blood flow data obtained during cycling exercise were categorized based on HR as follows: <100, 100-120, and >120 bpm. Blood flow in the RCV increased with the exercise intensity: by 16 ± 8, 32 ± 13, and 40 ± 19% from baseline, respectively. However, blood flow and vascular conductance in the ITRA and STRA did not change significantly with exercise. These findings demonstrate for the first time that ocular blood flow increases in the retina and choroid, but not in the arterioles, with increasing exercise intensity during dynamic exercise.

  2. Co-existing squamous cell carcinoma and hemangioma on the ocular surface of a cat.

    PubMed

    Perlmann, Eduardo; da Silva, Enry Garcia; Guedes, Pedro Mancini; Barros, Paulo Sergio de Moraes

    2010-01-01

    A 14-year-old spayed female domestic short-haired cat was presented for evaluation of a mass in the right eye. Ophthalmic examination revealed a blind right eye and presence of two distinct masses: a pink and a red-to-brown mass, the latter occupying most of the cornea and part of the conjunctiva. Exenteration was performed under general anesthesia, and the ocular tissues were processed routinely for histopathology. Upon microscopic examination, a malignant epithelial neoplasm and a benign vascular neoplasm were present in the cornea. The conjunctiva and the third eyelid were also affected. Upon immunohistochemistry, the epithelial tumor was positive for cytokeratin and negative for vimentin and the endothelial tumor was negative for cytokeratin and positive for vimentin. A diagnosis of squamous cell carcinoma (SCC) and hemangioma was made. The SCC was affecting the cornea, bulbar conjunctiva (lateral and inferior) and the base of the third eyelid, whereas the hemangioma was affecting the cornea and medial limbus. To the authors' knowledge, this is the first report of concomitant SCC and hemangioma affecting the ocular surface in a cat.

  3. A Comparative Study of the Therapeutic Potential of Mesenchymal Stem Cells and Limbal Epithelial Stem Cells for Ocular Surface Reconstruction.

    PubMed

    Holan, Vladimir; Trosan, Peter; Cejka, Cestmir; Javorkova, Eliska; Zajicova, Alena; Hermankova, Barbora; Chudickova, Milada; Cejkova, Jitka

    2015-09-01

    Stem cell-based therapy has become an attractive and promising approach for the treatment of severe injuries or thus-far incurable diseases. However, the use of stem cells is often limited by a shortage of available tissue-specific stem cells; therefore, other sources of stem cells are being investigated and tested. In this respect, mesenchymal stromal/stem cells (MSCs) have proven to be a promising stem cell type. In the present study, we prepared MSCs from bone marrow (BM-MSCs) or adipose tissue (Ad-MSCs) as well as limbal epithelial stem cells (LSCs), and their growth, differentiation, and secretory properties were compared. The cells were grown on nanofiber scaffolds and transferred onto the alkali-injured eye in a rabbit model, and their therapeutic potential was characterized. We found that BM-MSCs and tissue-specific LSCs had similar therapeutic effects. Clinical characterization of the healing process, as well as the evaluation of corneal thickness, re-epithelialization, neovascularization, and the suppression of a local inflammatory reaction, were comparable in the BM-MSC- and LSC-treated eyes, but results were significantly better than in injured, untreated eyes or in eyes treated with a nanofiber scaffold alone or with a nanofiber scaffold seeded with Ad-MSCs. Taken together, the results show that BM-MSCs' therapeutic effect on healing of injured corneal surface is comparable to that of tissue-specific LSCs. We suggest that BM-MSCs can be used for ocular surface regeneration in cases when autologous LSCs are absent or difficult to obtain. Damage of ocular surface represents one of the most common causes of impaired vision or even blindness. Cell therapy, based on transplantation of stem cells, is an optimal treatment. However, if limbal stem cells (LSCs) are not available, other sources of stem cells are tested. Mesenchymal stem cells (MSCs) are a convenient type of cell for stem cell therapy. The therapeutic potential of LSCs and MSCs was compared in an

  4. Extracellular vesicles mediate signaling between the aqueous humor producing and draining cells in the ocular system

    PubMed Central

    Lerner, Natalie; Avissar, Sofia

    2017-01-01

    Purpose Canonical Wnt signaling is associated with glaucoma pathogenesis and intraocular pressure (IOP) regulation. Our goal was to gain insight into the influence of non-pigmented ciliary epithelium (NPCE)-derived exosomes on Wnt signaling by trabecular meshwork (TM) cells. The potential impact of exosomes on Wnt signaling in the ocular drainage system remains poorly understood. Methods Exosomes isolated from media collected from cultured NPCE cells by differential ultracentrifugation were characterized by dynamic light scattering (DLS), tunable resistive pulse sensing (TRPS), and nanoparticle tracking analysis (NTA), sucrose density gradient migration and transmission electron microscopy (TEM). The cellular target specificity of the NPCE-derived exosomes was investigated by confocal microscopy-based monitoring of the uptake of DiD-labeled exosomes over time, as compared to uptake by various cell lines. Changes in Wnt protein levels in TM cells induced by NPCE exosomes were evaluated by Western blot. Results Exosomes derived from NPCE cells were purified and detected as small rounded 50–140 nm membrane vesicles, as defined by DLS, NTA, TRPS and TEM. Western blot analysis indicated that the nanovesicles were positive for classic exosome markers, including Tsg101 and Alix. Isolated nanoparticles were found in sucrose density fractions typical of exosomes (1.118–1.188 g/mL sucrose). Using confocal microscopy, we demonstrated time-dependent specific accumulation of the NPCE-derived exosomes in NTM cells. Other cell lines investigated hardly revealed any exosome uptake. We further showed that exosomes induced changes in Wnt signaling protein expression in the TM cells. Western blot analysis further revealed decreased phosphorylation of GKS3β and reduced β-catenin levels. Finally, we found that treatment of NTM cells with exosomes resulted in a greater than 2-fold decrease in the level of β-catenin in the cytosolic fraction. In contrast, no remarkable difference

  5. Extracellular vesicles mediate signaling between the aqueous humor producing and draining cells in the ocular system.

    PubMed

    Lerner, Natalie; Avissar, Sofia; Beit-Yannai, Elie

    2017-01-01

    Canonical Wnt signaling is associated with glaucoma pathogenesis and intraocular pressure (IOP) regulation. Our goal was to gain insight into the influence of non-pigmented ciliary epithelium (NPCE)-derived exosomes on Wnt signaling by trabecular meshwork (TM) cells. The potential impact of exosomes on Wnt signaling in the ocular drainage system remains poorly understood. Exosomes isolated from media collected from cultured NPCE cells by differential ultracentrifugation were characterized by dynamic light scattering (DLS), tunable resistive pulse sensing (TRPS), and nanoparticle tracking analysis (NTA), sucrose density gradient migration and transmission electron microscopy (TEM). The cellular target specificity of the NPCE-derived exosomes was investigated by confocal microscopy-based monitoring of the uptake of DiD-labeled exosomes over time, as compared to uptake by various cell lines. Changes in Wnt protein levels in TM cells induced by NPCE exosomes were evaluated by Western blot. Exosomes derived from NPCE cells were purified and detected as small rounded 50-140 nm membrane vesicles, as defined by DLS, NTA, TRPS and TEM. Western blot analysis indicated that the nanovesicles were positive for classic exosome markers, including Tsg101 and Alix. Isolated nanoparticles were found in sucrose density fractions typical of exosomes (1.118-1.188 g/mL sucrose). Using confocal microscopy, we demonstrated time-dependent specific accumulation of the NPCE-derived exosomes in NTM cells. Other cell lines investigated hardly revealed any exosome uptake. We further showed that exosomes induced changes in Wnt signaling protein expression in the TM cells. Western blot analysis further revealed decreased phosphorylation of GKS3β and reduced β-catenin levels. Finally, we found that treatment of NTM cells with exosomes resulted in a greater than 2-fold decrease in the level of β-catenin in the cytosolic fraction. In contrast, no remarkable difference in the amount of

  6. Prevalence of equine herpesvirus type 2 (EHV-2) DNA in ocular swabs and its cell tropism in equine conjunctiva.

    PubMed

    Borchers, K; Ebert, M; Fetsch, A; Hammond, T; Sterner-Kock, A

    2006-12-20

    Equine herpes virus 2 (EHV-2), a gamma(2)-herpesvirus, is common in horses of all ages. Its role as a primary pathogen is unclear but there is an association between EHV-2, respiratory disease and keratoconjunctivitis. The purpose of this study was to gain more information on the prevalence of EHV-2 DNA in conjunctival swabs from horses with and without ocular disease and to define the anatomical site and cell type harbouring viral genome or antigen. By polymerase chain reaction (PCR) 22 out of 77 (28.6%) ocular swabs of clinically healthy and only 4 out of 48 (8.3%) samples from diseased horses were positive. To define the main virus reservoir ocular tissue from 13 randomly selected horses without pathological evidence of ocular disease were analysed by nested PCR. In two horses optic nerve, lacrimal gland and conjunctiva, in further two cases lacrimal gland and conjunctiva and in four horses the conjunctiva only were EHV-2 PCR positive. For specifying the target cell we focused on conjunctivae and selected 3 out of 15 clinically healthy slaughterhouse horses positive for EHV-2 by PCR. In situ hybridisation on sections of these paraffin embedded conjunctivae localized viral genome in histiocyte-like cells of the submucosa. Immunohistochemical staining with an EHV-2 or S100 specific polyclonal antiserum demonstrated that Langerhans cells were co-localized in the same region of the sample section where virus positive cells were detected. Furthermore, we concluded that detection of viral antigen revealed a productive virus infection.

  7. Ocular Rosacea

    MedlinePlus

    ... Staff Ocular rosacea is inflammation that causes redness, burning and itching of the eyes. It often develops ... symptoms of ocular rosacea may include: Dry eyes Burning or stinging in the eyes Itchy eyes Grittiness ...

  8. Human ocular filariasis: further evidence on the zoonotic role of Onchocerca lupi

    PubMed Central

    2012-01-01

    Background Among ocular vector-borne pathogens, Onchocerca volvulus, the agent of the so-called “river blindness”, affects about 37 million people globally. Other Onchocerca spp. have been sporadically reported as zoonotic agents. Cases of canine onchocerciasis caused by Onchocerca lupi are on the rise in the United States and Europe. Its zoonotic role has been suspected but only recently ascertained in a single case from Turkey. The present study provides further evidence on the occurrence of O. lupi infesting human eyes in two patients from Turkey (case 1) and Tunisia (case 2). The importance of obtaining a correct sample collection and preparation of nematodes infesting human eyes is highlighted. Methods In both cases the parasites were identified with morpho-anatomical characters at the gross examination, histological analysis and anatomical description and also molecularly in case 1. Results The nematode from the first case was obviously O. lupi based on their morphology at the gross examination, histological analysis and anatomical description. In the second case, although the diagnostic cuticular characters were not completely developed, other features were congruent with the identification of O. lupi. Furthermore, the morphological identification was also molecularly confirmed in the Turkish case. Conclusions The results of this study suggest that O. lupi infestation is not an occasional finding but it should be considered in the differential diagnosis of other zoonotic helminths causing eye infestation in humans (e.g., D. immitis and Dirofilaria repens). Both cases came from areas where no cases of canine onchocerciasis were previously reported in the literature, suggesting that an in depth appraisal of the infestation in canine populations is necessary. Physicians and ophthalmologists are advised on how to preserve nematode samples recovered surgically, to allow a definitive, correct etiological diagnosis. PMID:22541132

  9. Dual adaptation and adaptive generalization of the human vestibulo-ocular reflex

    NASA Technical Reports Server (NTRS)

    Welch, R. B.; Bridgeman, B.; Williams, J. A.; Semmler, R.

    1998-01-01

    In two experiments, we examined the possibility that the human vestibulo-ocular reflex (VOR) is subject to dual adaptation (the ability to adapt to a sensory rearrangement more rapidly and/or more completely after repeated experience with it) and adaptive generalization (the ability to adapt more readily to a novel sensory rearrangement as a result of prior dual adaptation training). In Experiment 1, the subjects actively turned the head during alternating exposure to a visual-vestibular rearrangement (target/head gain = 0.5) and the normal situation (target/head gain = 0.0). These conditions produced both adaptation and dual adaptation of the VOR but no evidence of adaptive generalization when tested with a target/head gain of 1.0. Experiment 2, in which exposure to the 0.5 gain entailed externally controlled (i.e., passive) whole body rotation, resulted in VOR adaptation but no dual adaptation. As in Experiment 1, no evidence of adaptive generalization was found.

  10. Dual adaptation and adaptive generalization of the human vestibulo-ocular reflex

    NASA Technical Reports Server (NTRS)

    Welch, R. B.; Bridgeman, B.; Williams, J. A.; Semmler, R.

    1998-01-01

    In two experiments, we examined the possibility that the human vestibulo-ocular reflex (VOR) is subject to dual adaptation (the ability to adapt to a sensory rearrangement more rapidly and/or more completely after repeated experience with it) and adaptive generalization (the ability to adapt more readily to a novel sensory rearrangement as a result of prior dual adaptation training). In Experiment 1, the subjects actively turned the head during alternating exposure to a visual-vestibular rearrangement (target/head gain = 0.5) and the normal situation (target/head gain = 0.0). These conditions produced both adaptation and dual adaptation of the VOR but no evidence of adaptive generalization when tested with a target/head gain of 1.0. Experiment 2, in which exposure to the 0.5 gain entailed externally controlled (i.e., passive) whole body rotation, resulted in VOR adaptation but no dual adaptation. As in Experiment 1, no evidence of adaptive generalization was found.

  11. Absence of acute ocular damage in humans after prolonged exposure to intense RF EMF

    NASA Astrophysics Data System (ADS)

    Adibzadeh, F.; van Rhoon, G. C.; Verduijn, G. M.; Naus-Postema, N. C.; Paulides, M. M.

    2016-01-01

    The eye is considered to be a critical organ when determining safety standards for radio frequency (RF) radiation. Experimental data obtained using animals showed that RF heating of the eye, particularly over a specific threshold, can induce cataracts. During the treatment of cancer in the head and neck by hyperthermia, the eyes receive a considerable dose of RF radiation due to stray radiation from the prolonged (60 min) and intense exposure at 434 MHz of this region. In the current study, we verified the exposure guidelines for humans by determining the association between the electromagnetic and thermal dose in the eyes with the reported ocular effects. We performed a simulation study to retrospectively assess the specific absorption rate (SAR) and temperature increase in the eyes of 16 selected patients (encompassing a total of 74 treatment sessions) whose treatment involved high power delivery as well as a minimal distance between the tumor site and the eye. Our results show that the basic restrictions on the peak 10 g spatial-averaged SAR (10 W kg-1) and peak tissue temperature increase (1 °C) are exceeded by up to 10.4 and 4.6 times, on average, and by at least 6.2 and 1.8 times when considering the lower limit of the 95% confidence interval. Evaluation of the acute effects according to patients’ feedback (all patients), the common toxicity criteria scores (all patients) and an ophthalmology investigation (one patient with the highest exposure) revealed no indication of any serious acute ocular effect, even though the eyes were exposed to high electromagnetic fields, leading to a high thermal dose. We also found that, although there is a strong correlation (R 2  =  0.88) between the predicted induced SAR and temperature in the eye, there are large uncertainties regarding the temperature-SAR relationship. Given this large uncertainty (129%) compared with the uncertainty of 3D temperature simulations (61%), we recommend using temperature

  12. Absence of acute ocular damage in humans after prolonged exposure to intense RF EMF.

    PubMed

    Adibzadeh, F; van Rhoon, G C; Verduijn, G M; Naus-Postema, N C; Paulides, M M

    2016-01-21

    The eye is considered to be a critical organ when determining safety standards for radio frequency (RF) radiation. Experimental data obtained using animals showed that RF heating of the eye, particularly over a specific threshold, can induce cataracts. During the treatment of cancer in the head and neck by hyperthermia, the eyes receive a considerable dose of RF radiation due to stray radiation from the prolonged (60 min) and intense exposure at 434 MHz of this region. In the current study, we verified the exposure guidelines for humans by determining the association between the electromagnetic and thermal dose in the eyes with the reported ocular effects. We performed a simulation study to retrospectively assess the specific absorption rate (SAR) and temperature increase in the eyes of 16 selected patients (encompassing a total of 74 treatment sessions) whose treatment involved high power delivery as well as a minimal distance between the tumor site and the eye. Our results show that the basic restrictions on the peak 10 g spatial-averaged SAR (10 W kg(-1)) and peak tissue temperature increase (1 °C) are exceeded by up to 10.4 and 4.6 times, on average, and by at least 6.2 and 1.8 times when considering the lower limit of the 95% confidence interval. Evaluation of the acute effects according to patients' feedback (all patients), the common toxicity criteria scores (all patients) and an ophthalmology investigation (one patient with the highest exposure) revealed no indication of any serious acute ocular effect, even though the eyes were exposed to high electromagnetic fields, leading to a high thermal dose. We also found that, although there is a strong correlation (R (2) =  0.88) between the predicted induced SAR and temperature in the eye, there are large uncertainties regarding the temperature-SAR relationship. Given this large uncertainty (129%) compared with the uncertainty of 3D temperature simulations (61%), we recommend using temperature simulations as a

  13. Glycerol Monolaurate Inhibits Lipase Production by Clinical Ocular Isolates Without Affecting Bacterial Cell Viability.

    PubMed

    Flanagan, Judith Louise; Khandekar, Neeta; Zhu, Hua; Watanabe, Keizo; Markoulli, Maria; Flanagan, John Terence; Papas, Eric

    2016-02-01

    We sought to determine the relative lipase production of a range of ocular bacterial isolates and to assess the efficacy of glycerol monolaurate (GML) in inhibiting this lipase production in high lipase-producing bacteria without affecting bacterial cell growth. Staphylococcus aureus,Staphylococcus epidermidis,Propionibacterium acnes, and Corynebacterium spp. were inoculated at a density of 10(6)/mL in varying concentrations of GML up to 25 μg/mL for 24 hours at 37 °C with constant shaking. Bacterial suspensions were centrifuged, bacterial cell density was determined, and production of bacterial lipase was quantified using a commercial lipase assay kit. Staphylococcus spp. produced high levels of lipase activity compared with P. acnes and Corynebacterium spp. GML inhibited lipase production by Staphylococcal spp. in a dose-dependent manner, with S. epidermidis lipase production consistently more sensitive to GML than S. aureus. Glycerol monolaurate showed significant (P < 0.05) lipase inhibition above concentrations of 15 μg/mL in S. aureus and was not cytotoxic up to 25 μg/mL. For S. epidermidis, GML showed significant (P < 0.05) lipase inhibition above 7.5 μg/mL. Lipase activity varied between species and between strains. Staphylococcal spp. produced higher lipase activity compared with P. acnes and Corynebacterium spp. Glycerol monolaurate inhibited lipase production by S. aureus and S. epidermidis at concentrations that did not adversely affect bacterial cell growth. GML can be used to inhibit ocular bacterial lipase production without proving detrimental to commensal bacteria viability.

  14. Ocular immunopathologic findings of experimental onchocerciasis.

    PubMed

    Donnelly, J J; Rockey, J H; Bianco, A E; Soulsby, E J

    1984-04-01

    Ocular immunopathologic responses of inbred guinea pigs infected with Onchocerca microfilariae from domesticated animals were studied as a laboratory model of human ocular onchocerciasis. A single intracorneal infection of normal guinea pigs with microfilariae produced only minimal ocular lesions. In contrast, intracorneal infection of guinea pigs previously immunized by systemic infection with microfilariae produced intense corneal and uveal inflammation. Transfer of splenic lymphocytes from immunized donors to syngeneic normal recipients substituted effectively for the active immunization. Cell recipients produced marked corneal inflammatory reactions when challenged by a single intracorneal infection. Fresh and cryopreserved microfilariae produced identical reactions. The corneal inflammatory infiltrates were composed primarily of eosinophils, neutrophils, and plasma cells and resembled human onchocercal keratitis. Diethylcarbamazine citrate administration after a challenge intracorneal infection increased the severity of the corneal inflammatory response in immunized animals.

  15. Life under pressure: The role of ocular cribriform cells in preventing glaucoma.

    PubMed

    Paula, Jayter S; O'Brien, Colm; Stamer, W Daniel

    2016-10-01

    Primary open-angle glaucoma is a multifactorial blinding disease often impacting the two pressure-sensitive regions of the eye: the conventional outflow pathway and the optic nerve head (ONH). The connective tissues that span these two openings in the globe are the trabecular meshwork of the conventional outflow pathway and the lamina cribrosa of the ONH. Resident cribiform cells of these two regions are responsible for actively remodeling and maintaining their connective tissues. In glaucoma, aberrant maintenance of the juxtacanalicular tissues (JCT) of the conventional outflow pathway results in ocular hypertension and pathological remodeling of the lamina cribrosa results in ONH cupping, damaging retinal ganglion cell axons. Interestingly, cells cultured from the lamina cribrosa and the JCT of the trabecular meshwork have similarities regarding gene expression, protein production, plus cellular responses to growth factors and mechanical stimuli. This review compares and contrasts the current knowledge of these two cell types, whose health is critical for protecting the eye from glaucomatous changes. In response to pressure gradients across their respective cribiform tissues, the goal is to better understand and differentiate healthy from pathological behavior of these two cell types.

  16. Molecular Evidence and Functional Expression of a Novel Drug Efflux pump (ABCC2) in Human Corneal Epithelium and Rabbit Cornea and its role in Ocular drug efflux

    PubMed Central

    Karla, Pradeep K.; Pal, Dhananjay; Quinn, Tim; Mitra, Ashim K.

    2007-01-01

    Cornea is considered as a major barrier for ocular drug delivery. Low ocular bioavailability of drugs has been attributed primarily to low permeability across corneal epithelium thus leading to sub-therapeutic concentrations of drug in the eye and treatment failure. The role of drug efflux proteins, particularly the Pglycoprotein in ocular drug bioavailability has been reported. The objective of this research was to determine whether human corneal epithelium expresses multi drug resistance associated proteins contributing to drug efflux by employing both cultured corneal cells and freshly excised rabbit cornea. SV40 HCEC and rPCEC were selected for in-vitro testing. SV40-HCEC and freshly excised rabbit corneas were utilized for transport studies. [3H]-cyclosporine-A and [14C]-erythromycin which are known substrates for ABCC2 and MK-571, a specific inhibitor for MRP were applied in this study. RT-PCR indicated a unique and distinct band at ∼272 bp corresponding to ABCC2 in HCEC, SV40-HCEC, rabbit cornea, rPCEC and MDCKII-MRP2 cells. Also RT-PCR indicated a unique band ∼181 bp for HCEC and SV40-HCEC. Immunoprecipitation followed by Western Blot analysis revealed a specific band at ∼190-kDa in membrane fraction of SV40-HCEC, MDCKII-MRP2 and no band with isotype control. Uptake of [3H]-cyclosporine-A and [14C]-erythromycin in the presence of MK-571 was significantly enhanced than control in both SV40 HCEC and rPCEC. Similarly a significant elevation in (A→B) permeability of [3H]-cyclosporine-A and [14C]-erythromycin was observed in the presence of MK-571 in SV40-HCEC. A→B transport of [3H]-cyclosporine-A was elevated in the presence of MK-571 in freshly excised rabbit cornea indicating potential role of this efflux transporter and high clinical significance of this finding. PMID:17156953

  17. Recruitment of Donor T Cells to the Eyes During Ocular GVHD in Recipients of MHC-Matched Allogeneic Hematopoietic Stem Cell Transplants.

    PubMed

    Herretes, Samantha; Ross, Duncan B; Duffort, Stephanie; Barreras, Henry; Yaohong, Tan; Saeed, Ali M; Murillo, Juan C; Komanduri, Krishna V; Levy, Robert B; Perez, Victor L

    2015-04-01

    The primary objective of the present study was to identify the kinetics and origin of ocular infiltrating T cells in a preclinical model of graft-versus-host disease (GVHD) that induces eye tissue damage. Graft-versus-host disease was induced using an major histocompatibility complex (MHC)-matched, minor histocompatibility-mismatched hematopoietic stem cell transplant (HSCT) model. This approach, which utilized congenic and EGFP-labeled donor populations, mimics a matched, clinically unrelated donor (MUD) cell transplant. Systemic and ocular GVHD were assessed at varying time points using clinical examination, intravital microscopy, immune phenotype via flow cytometric analyses, and immunohistochemical staining. Following transplant, we observed characteristic changes in GVHD-associated immune phenotype as well as clinical signs present in recipients post transplant. Notably, the kinetics of the systemic changes and the ocular damage paralleled what is observed clinically, including damage to the cornea as well as the conjunctiva and lacrimal gland. Importantly, the infiltrate contained predominantly donor CD4 as well as CD8 T cells with an activated phenotype and macrophages together with effector cytokines consistent with the presence of a TH1 alloreactive population. Overall, the findings here unequivocally demonstrated that donor T cells compose part of the corneal and ocular adnexa infiltrate in animals undergoing ocular GVHD. In total, the results describe a novel and promising preclinical model characterized by both systemic and ocular changes as detected in significant numbers of patients undergoing GVHD following allo-HSCT, which can help facilitate dissecting the underlying immune mechanisms leading to damage associated with ocular GVHD.

  18. Velocity storage in the human vertical rotational vestibulo-ocular reflex.

    PubMed

    Bertolini, G; Ramat, S

    2011-03-01

    Human horizontal rotational vestibulo-ocular reflex (rVOR) has been extensively investigated: the horizontal semicircular canals sense yaw rotations with high-pass filter dynamics and a time constant (TC) around 5 s, yet the rVOR response shows a longer TC due to a central processing stage, known as velocity storage mechanism (VSM). It is generally assumed that the vertical rVOR behaves similarly to the horizontal one; however, VSM processing of the human vertical rVOR is still to be proven. We investigated the vertical rVOR in eight healthy human subjects using three experimental paradigms: (1) per- and post-rotatory around an earth-vertical axis (ear down rotations, EDR), (2) post-rotatory around an earth-horizontal axis with different stopping positions (static otolith stimulation), (3) per-rotatory around an earth-horizontal axis (dynamic otolith stimulation). We found that the TC of vertical rVOR responses ranged 3-10 s, depending both on gravity and on the direction of rotation. The shortest TC were found in response to post-rotatory earth-horizontal stimulation averaging 3.6 s, while they were prolonged in EDR stimulation, i.e. when the head angular velocity vector is aligned with gravity, with a mean value of about 6.0 s. Overall, the longest TC were observed in per-rotatory earth-horizontal stimulation, averaging 7.8 s. The finding of longer TC in EDR than in post-rotatory earth-horizontal stimulation indicates a role for the VSM in the vertical rVOR, although its contribution appears to be weaker than on the horizontal rVOR and may be directionally asymmetric. The results from per-rotatory earth-horizontal stimulation, instead, imply a role for the otoliths in controlling the duration of the vertical rVOR response. We found no reorientation of the response toward earth horizontal, indicating a difference between human and monkey rVOR.

  19. Effect of single-dose ivermectin therapy on human Onchocerca volvulus infection with onchocercal ocular involvement.

    PubMed Central

    Newland, H S; White, A T; Greene, B M; D'Anna, S A; Keyvan-Larijani, E; Aziz, M A; Williams, P N; Taylor, H R

    1988-01-01

    Ivermectin has shown promise as a potentially safe and effective microfilaricidal drug for the treatment of onchocerciasis. Several limited studies have shown it to have fewer side effects, especially ocular complications, than the currently available drug, diethylcarbamazine. The detailed ocular findings in 200 moderately to heavily infected Liberians who were enrolled in a safety and dose-finding study are presented. They received either 0, 100, 150, or 200 micrograms/kg of ivermectin and were followed up for 12 months. In clinical studies so far carried out ivermectin in a dose of 100, 150, or 200 micrograms/kg has not been associated with any major adverse reactions nor were there any sight-threatening effects even in the presence of severe ocular disease. Each of these doses significantly reduced the ocular microfilaria load for at least 12 months when compared with either the placebo (p less than 0.05) or pretreatment values (p less than 0.001). However, the 100 and 150 micrograms/kg doses caused fewer minor side effects than the higher dose. These results confirm that ivermectin in a single oral dose may be a safe and effective microfilaricidal drug for the treatment of onchocerciasis and that it appears to be free of major ocular side effects. Images PMID:3046657

  20. Effect of single-dose ivermectin therapy on human Onchocerca volvulus infection with onchocercal ocular involvement.

    PubMed

    Newland, H S; White, A T; Greene, B M; D'Anna, S A; Keyvan-Larijani, E; Aziz, M A; Williams, P N; Taylor, H R

    1988-08-01

    Ivermectin has shown promise as a potentially safe and effective microfilaricidal drug for the treatment of onchocerciasis. Several limited studies have shown it to have fewer side effects, especially ocular complications, than the currently available drug, diethylcarbamazine. The detailed ocular findings in 200 moderately to heavily infected Liberians who were enrolled in a safety and dose-finding study are presented. They received either 0, 100, 150, or 200 micrograms/kg of ivermectin and were followed up for 12 months. In clinical studies so far carried out ivermectin in a dose of 100, 150, or 200 micrograms/kg has not been associated with any major adverse reactions nor were there any sight-threatening effects even in the presence of severe ocular disease. Each of these doses significantly reduced the ocular microfilaria load for at least 12 months when compared with either the placebo (p less than 0.05) or pretreatment values (p less than 0.001). However, the 100 and 150 micrograms/kg doses caused fewer minor side effects than the higher dose. These results confirm that ivermectin in a single oral dose may be a safe and effective microfilaricidal drug for the treatment of onchocerciasis and that it appears to be free of major ocular side effects.

  1. Sef is a negative regulator of fiber cell differentiation in the ocular lens.

    PubMed

    Newitt, Peter; Boros, Jessica; Madakashira, Bhavani P; Robinson, Michael L; Reneker, Lixing W; McAvoy, John W; Lovicu, Frank J

    2010-07-01

    Growth factor signaling, mediated via receptor tyrosine kinases (RTKs), needs to be tightly regulated in many developmental systems to ensure a physiologically appropriate biological outcome. At one level this regulation may involve spatially and temporally ordered patterns of expression of specific RTK signaling antagonists, such as Sef (similar expression to fgfs). Growth factors, notably FGFs, play important roles in development of the vertebrate ocular lens. FGF induces lens cell proliferation and differentiation at progressively higher concentrations and there is compelling evidence that a gradient of FGF signaling in the eye determines lens polarity and growth patterns. We have recently identified the presence of Sef in the lens, with strongest expression in the epithelial cells. Given the important role for FGFs in lens developmental biology, we employed transgenic mouse strategies to determine if Sef could be involved in regulating lens cell behaviour. Over-expressing Sef specifically in the lens of transgenic mice led to impaired lens and eye development that resulted in microphthalmia. Sef inhibited primary lens fiber cell elongation and differentiation, as well as increased apoptosis, consistent with a block in FGFR-mediated signaling during lens morphogenesis. These results are consistent with growth factor antagonists, such as Sef, being important negative regulators of growth factor signaling. Moreover, the lens provides a useful paradigm as to how opposing gradients of a growth factor and its antagonist could work together to determine and stabilise tissue patterning during development and growth.

  2. Ocular motor responses to abrupt interaural head translation in normal humans

    NASA Technical Reports Server (NTRS)

    Ramat, Stefano; Zee, David S.; Shelhamer, M. J. (Principal Investigator)

    2003-01-01

    We characterized the interaural translational vestibulo-ocular reflex (tVOR) in 6 normal humans to brief (approximately 200 ms), high-acceleration (0.4-1.4g) stimuli, while they fixed targets at 15 or 30 cm. The latency was 19 +/- 5 ms at 15-cm and 20 +/- 12 ms at 30-cm viewing. The gain was quantified using the ratio of actual to ideal behavior. The median position gain (at time of peak head velocity) was 0.38 and 0.37, and the median velocity gain, 0.52 and 0.62, at 15- and 30-cm viewing, respectively. These results suggest the tVOR scales proportionally at these viewing distances. Likewise, at both viewing distances, peak eye velocity scaled linearly with peak head velocity and gain was independent of peak head acceleration. A saccade commonly occurred in the compensatory direction, with a greater latency (165 vs. 145 ms) and lesser amplitude (1.8 vs. 3.2 deg) at 30- than 15-cm viewing. Even with saccades, the overall gain at the end of head movement was still considerably undercompensatory (medians 0.68 and 0.77 at 15- and 30-cm viewing). Monocular viewing was also assessed at 15-cm viewing. In 4 of 6 subjects, gains were the same as during binocular viewing and scaled closely with vergence angle. In sum the low tVOR gain and scaling of the response with viewing distance and head velocity extend previous results to higher acceleration stimuli. tVOR latency (approximately 20 ms) was lower than previously reported. Saccades are an integral part of the tVOR, and also scale with viewing distance.

  3. Ocular motor responses to abrupt interaural head translation in normal humans.

    PubMed

    Ramat, Stefano; Zee, David S

    2003-08-01

    We characterized the interaural translational vestibulo-ocular reflex (tVOR) in 6 normal humans to brief (approximately 200 ms), high-acceleration (0.4-1.4g) stimuli, while they fixed targets at 15 or 30 cm. The latency was 19 +/- 5 ms at 15-cm and 20 +/- 12 ms at 30-cm viewing. The gain was quantified using the ratio of actual to ideal behavior. The median position gain (at time of peak head velocity) was 0.38 and 0.37, and the median velocity gain, 0.52 and 0.62, at 15- and 30-cm viewing, respectively. These results suggest the tVOR scales proportionally at these viewing distances. Likewise, at both viewing distances, peak eye velocity scaled linearly with peak head velocity and gain was independent of peak head acceleration. A saccade commonly occurred in the compensatory direction, with a greater latency (165 vs. 145 ms) and lesser amplitude (1.8 vs. 3.2 deg) at 30- than 15-cm viewing. Even with saccades, the overall gain at the end of head movement was still considerably undercompensatory (medians 0.68 and 0.77 at 15- and 30-cm viewing). Monocular viewing was also assessed at 15-cm viewing. In 4 of 6 subjects, gains were the same as during binocular viewing and scaled closely with vergence angle. In sum the low tVOR gain and scaling of the response with viewing distance and head velocity extend previous results to higher acceleration stimuli. tVOR latency (approximately 20 ms) was lower than previously reported. Saccades are an integral part of the tVOR, and also scale with viewing distance.

  4. Interaction between otolith organ and semicircular canal vestibulo-ocular reflexes during eccentric rotation in humans.

    PubMed

    Gianna-Poulin, Claire C; Peterka, Robert J

    2008-03-01

    Controversy remains about the linearity of the interaction between horizontal semicircular canal and otolith organ vestibulo-ocular reflexes (VORs) in the generation of horizontal eye movements during head movements including both rotational and translational components. We used three eccentric rotation techniques to investigate this interaction in human subjects: (1) the tangential interaural acceleration was varied using three head positions (on-axis, 25 and 40 cm ahead of the rotational axis), while angular head velocity remained unchanged; (2) the magnitude of the angular head velocity was varied with head eccentricity to keep the tangential interaural acceleration unchanged; (3) the subject's head was oriented either upright or 90 degrees forward from upright (nose-down). Experiments were performed in complete darkness with the subjects remembering a close earth-fixed target (20 cm distant) while being rotated at 1.2 and 1.8 Hz. Our data showed that the translational component of the VOR evoked during eccentric yaw rotation increased proportionally with an increase in head eccentricity, i.e. with tangential acceleration. We also found that the translational component of the VOR was equal for motion stimuli producing identical interaural tangential accelerations even when angular velocities differed. In addition, we found that the translational component of the VOR evoked during head upright eccentric rotation was equal to the translational VOR evoked during nose-down rotation for a given stimulus and head eccentricity. We conclude that these three findings are in agreement with what would be expected from a linear interaction (i.e. algebraic summation) between otolith organ and horizontal canal VORs for the generation of horizontal compensatory eye movements during head motion.

  5. Manifestation of ocular-muscle EMG contamination in human intracranial recordings

    PubMed Central

    Kovach, Christopher K.; Tsuchiya, Naotsugu; Kawasaki, Hiroto; Oya, Hiroyuki; Howard, Mathew A.; Adolphs, Ralph

    2010-01-01

    It is widely assumed that intracranial recordings from the brain are only minimally affected by contamination due to ocular-muscle electromyogram (oEMG). Here we show that this is not always the case. In intracranial recordings from five surgical epilepsy patients we observed that eye movements caused a transient biphasic potential at the onset of a saccade, resembling the saccadic spike potential commonly seen in scalp EEG, accompanied by an increase in broadband power between 20 and 200 Hz. Using concurrently recorded eye movements and high-density intracranial EEG (iEEG) we developed a detailed overview of the spatial distribution and temporal characteristics of the saccade-related oculomotor signal within recordings from ventral, medial and lateral temporal cortex. The occurrence of the saccadic spike was not explained solely by reference contact location, and was observed near the temporal pole for small (< 2 deg) amplitude saccades and over a broad area for larger saccades. We further examined the influence of saccade-related oEMG contamination on measurements of spectral power and interchannel coherence. Contamination manifested in both spectral power and coherence measurements, in particular, over the anterior half of the ventral and medial temporal lobe. Next, we compared methods for removing the contaminating signal and found that nearest-neighbor bipolar re-referencing and ICA filtering were effective for suppressing oEMG at locations far from the orbits, but tended to leave some residual contamination at the temporal pole. Finally, we show that genuine cortical broadband gamma responses observed in averaged data from ventral temporal cortex can bear a striking similarity in time course and band-width to oEMG contamination recorded at more anterior locations. We conclude that eye movement-related contamination should be ruled out when reporting high gamma responses in human intracranial recordings, especially those obtained near anterior and medial

  6. Ocular motor responses to abrupt interaural head translation in normal humans

    NASA Technical Reports Server (NTRS)

    Ramat, Stefano; Zee, David S.; Shelhamer, M. J. (Principal Investigator)

    2003-01-01

    We characterized the interaural translational vestibulo-ocular reflex (tVOR) in 6 normal humans to brief (approximately 200 ms), high-acceleration (0.4-1.4g) stimuli, while they fixed targets at 15 or 30 cm. The latency was 19 +/- 5 ms at 15-cm and 20 +/- 12 ms at 30-cm viewing. The gain was quantified using the ratio of actual to ideal behavior. The median position gain (at time of peak head velocity) was 0.38 and 0.37, and the median velocity gain, 0.52 and 0.62, at 15- and 30-cm viewing, respectively. These results suggest the tVOR scales proportionally at these viewing distances. Likewise, at both viewing distances, peak eye velocity scaled linearly with peak head velocity and gain was independent of peak head acceleration. A saccade commonly occurred in the compensatory direction, with a greater latency (165 vs. 145 ms) and lesser amplitude (1.8 vs. 3.2 deg) at 30- than 15-cm viewing. Even with saccades, the overall gain at the end of head movement was still considerably undercompensatory (medians 0.68 and 0.77 at 15- and 30-cm viewing). Monocular viewing was also assessed at 15-cm viewing. In 4 of 6 subjects, gains were the same as during binocular viewing and scaled closely with vergence angle. In sum the low tVOR gain and scaling of the response with viewing distance and head velocity extend previous results to higher acceleration stimuli. tVOR latency (approximately 20 ms) was lower than previously reported. Saccades are an integral part of the tVOR, and also scale with viewing distance.

  7. Three-dimensional analysis of otolith-ocular reflex during eccentric rotation in humans.

    PubMed

    Takimoto, Yasumitsu; Imai, Takao; Okumura, Tomoko; Takeda, Noriaki; Inohara, Hidenori

    2016-10-01

    When a participant is rotated while displaced from the axis of rotation (eccentric rotation, ER), both rotational stimulation and linear acceleration are applied to the participant. As linear acceleration stimulates the otolith, the vestibulo-ocular reflex (VOR) caused by the otolith (linear VOR; lVOR) would be induced during ER. Ten participants were rotated sinusoidally at a maximum angular velocity of 50°/s and at frequencies of 0.1, 0.3, 0.5, and 0.7Hz. The radius of rotation during ER was 90cm. The participants sat on a chair at three different positions: on the axis (center rotation, CR), at 90cm backward from the axis (nose-in ER, NI-ER) and at 90cm forward from the axis (nose-out ER, NO-ER). Their eye movements during rotation were recorded and analyzed three-dimensionally. The VOR gain during NI-ER was lower at 0.5 and 0.7Hz, and that during NO-ER was higher at 0.3, 0.5, and 0.7Hz than during CR. These results indicate that lVOR actually worked at 0.5 and 0.7Hz during ER and that the enhancement and decline of the VOR gain relative to the VOR gain during CR was seen in humans. Thus, we suggest that otolith function can be assessed via rotational testing of NI-ER and NO-ER. Copyright © 2016 Elsevier Ireland Ltd and Japan Neuroscience Society. All rights reserved.

  8. Characteristics of primary extranodal marginal zone B-cell lymphoma in Korea: conjunctiva versus other ocular adnexa.

    PubMed

    Nam, Seung Wan; Woo, Kyung In; Kim, Yoon-Duck

    2017-08-16

    To compare the clinical characteristics and prognosis of primary conjunctival versus other ocular adnexal extranodal marginal zone B-cell lymphoma (EMZL). Retrospective review of clinical records for all consecutive patients with primary ocular adnexal EMZL treated from March 1995 to December 2015. 198 patients were evaluated including 81 with primary conjunctival and 117 with other ocular adnexal EMZL. Conjunctival EMZL was found at a younger age (40.3±10.3vs 54.3±13.4 years, p<0.0001) with a female predilection (75.3%vs35.9%, p<0.0001) and had a higher rate of bilaterality (40.7%vs11.1%, p<0.0001) and a lower rate of systemic involvement (1.2%vs9.4%, p=0.030) compared with other ocular adnexal EMZLs. Conjunctival EMZL also showed a higher rate of complete response to primary treatment (98.8%vs89.5%, p=0.016) than other ocular adnexal EMZLs; however, recurrence and lymphoma-related death rates were not different between the two groups (p>0.05). Kaplan-Meier estimates for disease-specific survival at 5 and 10 years were 98.2% and 98.2% in conjunctival and 98.6%, respectively, and 95.2% in other ocular adnexal EMZLs. Univariate analysis showed that systemic involvement was negatively associated with conjunctival tumour location and positively associated with age (OR=0.35 and OR=1.05, p=0.045 and p=0.012, respectively), and treatment response was positively associated with conjunctival tumour location and negatively associated with age (OR=3.02 and OR=0.95, p=0.035 and p=0.009, respectively). Conjunctival EMZL shows unique demographic characteristic compared with other ocular adnexal EMZLs. Long-term follow-up is required due to late recurrence in ocular adnexal EMZL. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  9. Non-human Immunodeficiency Virus-related Ocular Syphilis in a Korean Population: Clinical Manifestations and Treatment Outcomes

    PubMed Central

    Kim, Yonguk; Kwak, Hyung Woo

    2016-01-01

    Purpose To describe the clinical manifestations and treatment outcomes of ocular syphilis in patients without human immunodeficiency virus (HIV) infection. Methods A total of 45 eyes from 39 patients with ocular syphilis confirmed by serologic tests were reviewed retrospectively. The included cases were all non-HIV-infected patients presenting with intraocular inflammation from 2002 to 2014 at Kyung Hee University Hospital. Medical records of 45 eyes were analyzed and included best-corrected visual acuity and ophthalmologic examination findings of the anterior and posterior segments to determine the focus of inflammation. Optical coherence tomography and fluorescein angiography findings as well as both medical and surgical management were also analyzed. Results The mean patient age was 61.0 years (range, 37 to 89 years). Bilateral ocular involvement occurred in 6 patients (15.4%), and diagnoses at presentation were most frequently related to posterior uveitis (38%), followed by panuveitis (29%) and optic neuritis (11%). Isolated interstitial keratitis and intermediate uveitis were uncommon (4%, both). Twenty-eight eyes (62.2%) were treated with penicillin, and 11 eyes (24.4%) underwent surgical treatment. The mean baseline best corrected visual acuity was 0.79 ± 0.59 (mean ± standard deviation, logarithm of the minimum angle of resolution) and significantly improved to 0.60 ± 0.63 at the final follow-up after treatment (p = 0.019). Mean visual improvement was significantly greater in the penicillin-treated group (p = 0.001). Visual impairment at the final visit occurred in 11 eyes (24.4%). Among the visual impairment group, 10 eyes (90.1%) had posterior segment-involving uveitis. Conclusions Visual outcomes of treated, non-HIV-related ocular syphilis were favorable regardless of time to presentation. Posterior segment-involving uveitis at presentation was associated with poor visual outcome. PMID:27729756

  10. Ocular Reflex Phase During Off-Vertical Axis Rotation In Humans Is Modified By Head-On-Trunk Position

    NASA Technical Reports Server (NTRS)

    Wood, Scott; Clement, Gilles; Denise, Pierre; Reschke, Millard

    2005-01-01

    Constant velocity Off-Vertical Axis Rotation (OVAR) imposes a continuously varying orientation of the head and body relative to gravity. The ensuing ocular reflexes include modulation of both horizontal and torsional eye velocity as a function of the varying linear acceleration along the lateral plane. The purpose of this study was to examine whether the modulation of these ocular reflexes would be modified by different head-on-trunk positions. Ten human subjects were rotated in darkness about their longitudinal axis 20 deg off-vertical at constant rates of 45 and 180 deg/s, corresponding to 0.125 and 0.5 Hz. Binocular responses were obtained with video-oculography with the head and trunk aligned, and then with the head turned relative to the trunk 40 deg to the right or left of center. Sinusoidal curve fits were used to derive amplitude, phase and bias velocity of the eye movements across multiple cycles for each head-on-trunk position. Consistent with previous studies, the modulation of torsional eye movements was greater at 0.125 Hz while the modulation of horizontal eye movements was greater at 0.5 Hz. Neither amplitude nor bias velocities were significantly altered by head-on-trunk position. The phases of both torsional and horizontal ocular reflexes, on the other hand, shifted towards alignment with the head. These results are consistent with the modulation of torsional and horizontal ocular reflexes during OVAR being primarily mediated by the otoliths in response to the sinusoidally varying linear acceleration along the interaural head axis.

  11. Ocular Reflex Phase During Off-Vertical Axis Rotation In Humans Is Modified By Head-On-Trunk Position

    NASA Technical Reports Server (NTRS)

    Wood, Scott; Clement, Gilles; Denise, Pierre; Reschke, Millard

    2005-01-01

    Constant velocity Off-Vertical Axis Rotation (OVAR) imposes a continuously varying orientation of the head and body relative to gravity. The ensuing ocular reflexes include modulation of both horizontal and torsional eye velocity as a function of the varying linear acceleration along the lateral plane. The purpose of this study was to examine whether the modulation of these ocular reflexes would be modified by different head-on-trunk positions. Ten human subjects were rotated in darkness about their longitudinal axis 20 deg off-vertical at constant rates of 45 and 180 deg/s, corresponding to 0.125 and 0.5 Hz. Binocular responses were obtained with video-oculography with the head and trunk aligned, and then with the head turned relative to the trunk 40 deg to the right or left of center. Sinusoidal curve fits were used to derive amplitude, phase and bias velocity of the eye movements across multiple cycles for each head-on-trunk position. Consistent with previous studies, the modulation of torsional eye movements was greater at 0.125 Hz while the modulation of horizontal eye movements was greater at 0.5 Hz. Neither amplitude nor bias velocities were significantly altered by head-on-trunk position. The phases of both torsional and horizontal ocular reflexes, on the other hand, shifted towards alignment with the head. These results are consistent with the modulation of torsional and horizontal ocular reflexes during OVAR being primarily mediated by the otoliths in response to the sinusoidally varying linear acceleration along the interaural head axis.

  12. Inhibition of neutral sphingomyelinase decreases elevated levels of inducible nitric oxide synthase and apoptotic cell death in ocular hypertensive rats

    SciTech Connect

    Aslan, Mutay; Basaranlar, Goksun; Unal, Mustafa; Ciftcioglu, Akif; Derin, Narin; Mutus, Bulent

    2014-11-01

    Endoplasmic reticulum (ER) stress and excessive nitric oxide production via induction of inducible nitric oxide synthase (NOS2) have been implicated in the pathogenesis of neuronal retinal cell death in ocular hypertension. Neutral sphingomyelinase (N-SMase)/ceramide pathway can regulate NOS2 expression, hence this study determined the role of selective neutral sphingomyelinase (N-SMase) inhibition on retinal NOS2 levels, ER stress, apoptosis and visual evoked potentials (VEPs) in a rat model of elevated intraocular pressure (EIOP). NOS2 expression and retinal protein nitration were significantly greater in EIOP and significantly decreased with N-SMase inhibition. A significant increase was observed in retinal ER stress markers pPERK, CHOP and GRP78 in EIOP, which were not significantly altered by N-SMase inhibition. Retinal TUNEL staining showed increased apoptosis in all EIOP groups; however N-SMase inhibition significantly decreased the percent of apoptotic cells in EIOP. Caspase-3, -8 and -9 activities were significantly increased in EIOP and returned to baseline levels following N-SMase inhibition. Latencies of all VEP components were significantly prolonged in EIOP and shortened following N-SMase inhibition. Data confirm the role of nitrative injury in EIOP and highlight the protective effect of N-SMase inhibition in EIOP via down-regulation of NOS2 levels and nitrative stress. - Highlights: • Inhibition of N-SMase decreases NOS2 levels in ocular hypertension. • Inhibition of N-SMase decreases protein nitration in ocular hypertension. • Inhibition of N-SMase decreases caspase activation in ocular hypertension. • Inhibition of N-SMase decreases apoptosis in ocular hypertension.

  13. [Ocular allergies].

    PubMed

    Messmer, E M

    2005-05-01

    Recent developments indicate that ocular allergy is more than an IgE-mediated allergic conjunctivitis. Ocular allergy is a disease affecting the entire ocular surface including conjunctiva, lids, cornea, lacrimal gland and tear film. Besides an IgE-mediated reaction, a complex chronic inflammation is involved in the pathogenesis of many ocular allergies. According to their pathogenesis and clinical picture, ocular allergies are classified into mild forms, such as seasonal and perennial allergic conjunctivitis as well as giant papillary conjunctivitis, and chronic, potentially blinding forms such as atopic keratoconjunctivitis and vernal keratoconjunctivitis. New therapeutics act on the entire inflammatory process or try to modulate the allergic reaction early and specifically. The association with non-ocular allergic symptoms requires an interdisciplinary approach.

  14. The dynamic contributions of the otolith organs to human ocular torsion

    NASA Technical Reports Server (NTRS)

    Merfeld, D. M.; Teiwes, W.; Clarke, A. H.; Scherer, H.; Young, L. R.

    1996-01-01

    We measured human ocular torsion (OT) monocularly (using video) and binocularly (using search coils) while sinusoidally accelerating (0.7 g) five human subjects along an earth-horizontal axis at five frequencies (0.35, 0.4, 0.5, 0.75, and 1.0 Hz). The compensatory nature of OT was investigated by changing the relative orientation of the dynamic (linear acceleration) and static (gravitational) cues. Four subject orientations were investigated: (1) Y-upright-acceleration along the interaural (y) axis while upright; (2) Y-supine-acceleration along the y-axis while supine; (3) Z-RED-acceleration along the dorsoventral (z) axis with right ear down; (4) Z-supine-acceleration along the z-axis while supine. Linear acceleration in the Y-upright, Y-supine and Z-RED orientations elicited conjugate OT. The smaller response in the Z-supine orientation appeared disconjugate. The amplitude of the response decreased and the phase lag increased with increasing frequency for each orientation. This frequency dependence does not match the frequency response of the regular or irregular afferent otolith neurons; therefore the response dynamics cannot be explained by simple peripheral mechanisms. The Y-upright responses were larger than the Y-supine responses (P < 0.05). This difference indicates that OT must be more complicated than a simple low-pass filtered response to interaural shear force, since the dynamic shear force along the interaural axis was identical in these two orientations. The Y-supine responses were, in turn, larger than the Z-RED responses (P < 0.01). Interestingly, the vector sum of the Y-supine responses plus Z-RED responses was not significantly different (P = 0.99) from the Y-upright responses. This suggests that, in this frequency range, the conjugate OT response during Y-upright stimulation might be composed of two components: (1) a response to shear force along the y-axis (as in Y-supine stimulation), and (2) a response to roll tilt of gravitoinertial force (as

  15. The dynamic contributions of the otolith organs to human ocular torsion

    NASA Technical Reports Server (NTRS)

    Merfeld, D. M.; Teiwes, W.; Clarke, A. H.; Scherer, H.; Young, L. R.

    1996-01-01

    We measured human ocular torsion (OT) monocularly (using video) and binocularly (using search coils) while sinusoidally accelerating (0.7 g) five human subjects along an earth-horizontal axis at five frequencies (0.35, 0.4, 0.5, 0.75, and 1.0 Hz). The compensatory nature of OT was investigated by changing the relative orientation of the dynamic (linear acceleration) and static (gravitational) cues. Four subject orientations were investigated: (1) Y-upright-acceleration along the interaural (y) axis while upright; (2) Y-supine-acceleration along the y-axis while supine; (3) Z-RED-acceleration along the dorsoventral (z) axis with right ear down; (4) Z-supine-acceleration along the z-axis while supine. Linear acceleration in the Y-upright, Y-supine and Z-RED orientations elicited conjugate OT. The smaller response in the Z-supine orientation appeared disconjugate. The amplitude of the response decreased and the phase lag increased with increasing frequency for each orientation. This frequency dependence does not match the frequency response of the regular or irregular afferent otolith neurons; therefore the response dynamics cannot be explained by simple peripheral mechanisms. The Y-upright responses were larger than the Y-supine responses (P < 0.05). This difference indicates that OT must be more complicated than a simple low-pass filtered response to interaural shear force, since the dynamic shear force along the interaural axis was identical in these two orientations. The Y-supine responses were, in turn, larger than the Z-RED responses (P < 0.01). Interestingly, the vector sum of the Y-supine responses plus Z-RED responses was not significantly different (P = 0.99) from the Y-upright responses. This suggests that, in this frequency range, the conjugate OT response during Y-upright stimulation might be composed of two components: (1) a response to shear force along the y-axis (as in Y-supine stimulation), and (2) a response to roll tilt of gravitoinertial force (as

  16. Novel Scoring Criteria for the Evaluation of Ocular Graft-versus-Host Disease in a Preclinical Allogeneic Hematopoietic Stem Cell Transplantation Animal Model.

    PubMed

    Perez, Victor L; Barsam, Alexander; Duffort, Stephanie; Urbieta, Maitee; Barreras, Henry; Lightbourn, Casey; Komanduri, Krishna V; Levy, Robert B

    2016-10-01

    Ocular complications occur after transplantation in 60% to 90% of chronic graft-versus-host disease (GVHD) patients and significantly impair vision-related quality of life. Ocular surface inflammation and dry eye disease are the most common manifestations of ocular GVHD. Ocular GVHD can be viewed as an excellent preclinical model that can be studied to understand the immune pathogenesis of this common and debilitating disease. A limitation of this is that only a few experimental models mimic the ocular complications after hematopoietic stem cell transplantation (HSCT) and have focused on the acute GVHD process. To address this issue, we used a preclinical animal model developed by our group where ocular involvement was preceded by systemic GVHD to gain insight regarding the contributing immune mechanisms. Employing this "matched unrelated donor" model enabled the development of clinical scoring criteria, which readily identified different degrees of ocular pathology at both the ocular surface and adnexa, dependent on the level of conditioning before HSCT. As far as we are aware, we report for the first time that these clinical and immune responses occur not only on the ocular surface, but they also heavily involve the lid margin region. In total, the present study reports a preclinical scoring model that can be applied to animal models as investigators look to further explore GVHD's immunologic effects at the level of the ocular surface and eyelid adnexa compartments. We speculate that future studies will use this clinical scoring index in combination with what is recognized histologically and correlated with serum biomarkers identified in chronic/ocular GVHD. Copyright © 2016 The American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  17. A First Human Case of Ocular Dirofilariosis due to Dirofilaria repens in Northeastern France

    PubMed Central

    Argy, Nicolas; Sabou, Marcela; Billing, Alain; Hermsdorff, Christian; Candolfi, Ermanno; Abou-Bacar, Ahmed

    2011-01-01

    We report the first case of ocular dirofilariasis to be diagnosed in northeast France (Alsace region), in a man who presented with a suborbital mass after a journey to Senegal. Microscopic examination of the surgical specimen identified Dirofilaria repens. PMID:21461355

  18. Human ocular torsion during parabolic flights: an analysis with scleral search coil

    NASA Technical Reports Server (NTRS)

    Cheung, B. S.; Money, K.; Howard, I.; Kirienko, N.; Johnson, W.; Lackner, J.; Dizio, P.; Evanoff, J.

    1992-01-01

    Rotation of the eyes about the visual axis is known as ocular torsion. A lateral inclination (a "roll") of the head induces ocular torsion in the opposite direction, a response known as ocular counterrolling. For six subjects, we recorded the static (head still) and dynamic (head in oscillatory roll motion) ocular torsion in normal 1 g condition and also during the microgravity and hypergravity periods of parabolic flight, using the electromagnetic scleral search coil technique. With the head still, the direction and magnitude of torsion that occurred in response to microgravity and hypergravity differed substantially from one individual to another, but there was a significant difference in torsional magnitude between the microgravity and hypergravity periods, for all static head positions including the upright position. Under normal 1 g conditions, counterrolling compensated for about 16% of (voluntary) static head roll, while dynamic counterroll was much larger, up to 36% of head roll at 0.55 Hz. With increasing frequency of head oscillation between 0.33 Hz and 0.55 Hz, the gain of counterrolling increased and there was no change in the phase relationship. The gain of dynamic counterroll (in response to voluntary head rolling) was not significantly less in hypogravity, suggesting that on the ground at these frequencies the contribution of gravity and gravity receptors to this reflex is redundant: this reflex is probably driven by the semicircular canals. In some subjects, the torsional displacement in microgravity is accompanied by micro-torsional oscillatory motion.

  19. Human ocular torsion during parabolic flights: an analysis with scleral search coil

    NASA Technical Reports Server (NTRS)

    Cheung, B. S.; Money, K.; Howard, I.; Kirienko, N.; Johnson, W.; Lackner, J.; Dizio, P.; Evanoff, J.

    1992-01-01

    Rotation of the eyes about the visual axis is known as ocular torsion. A lateral inclination (a "roll") of the head induces ocular torsion in the opposite direction, a response known as ocular counterrolling. For six subjects, we recorded the static (head still) and dynamic (head in oscillatory roll motion) ocular torsion in normal 1 g condition and also during the microgravity and hypergravity periods of parabolic flight, using the electromagnetic scleral search coil technique. With the head still, the direction and magnitude of torsion that occurred in response to microgravity and hypergravity differed substantially from one individual to another, but there was a significant difference in torsional magnitude between the microgravity and hypergravity periods, for all static head positions including the upright position. Under normal 1 g conditions, counterrolling compensated for about 16% of (voluntary) static head roll, while dynamic counterroll was much larger, up to 36% of head roll at 0.55 Hz. With increasing frequency of head oscillation between 0.33 Hz and 0.55 Hz, the gain of counterrolling increased and there was no change in the phase relationship. The gain of dynamic counterroll (in response to voluntary head rolling) was not significantly less in hypogravity, suggesting that on the ground at these frequencies the contribution of gravity and gravity receptors to this reflex is redundant: this reflex is probably driven by the semicircular canals. In some subjects, the torsional displacement in microgravity is accompanied by micro-torsional oscillatory motion.

  20. A Novel Cell-Associated Protection Assay Demonstrates the Ability of Certain Antibiotics To Protect Ocular Surface Cell Lines from Subsequent Clinical Staphylococcus aureus Challenge▿†

    PubMed Central

    Wingard, J. B.; Romanowski, E. G.; Kowalski, R. P.; Mah, F. S.; Ling, Y.; Bilonick, R. A.; Shanks, R. M. Q.

    2011-01-01

    In vivo effectiveness of topical antibiotics may depend on their ability to associate with epithelial cells to provide continued protection, but this contribution is not measured by standard antibiotic susceptibility tests. We report a new in vitro method that measures the ability of test antibiotics azithromycin (AZM), erythromycin (ERY), tetracycline (TET), and bacitracin (BAC) to associate with mammalian cells and to protect these cells from destruction by bacteria. Mammalian cell lines were grown to confluence using antibiotic-free medium and then incubated in medium containing a single antibiotic (0 to 512 μg/ml). After incubation, the cells were challenged with Staphylococcus aureus ocular isolates, without antibiotics added to the culture medium. Epithelial cell layer integrity was assessed by gentian violet staining, and the minimum cell layer protective concentration (MCPC) of an antibiotic sufficient to protect the mammalian cells from S. aureus was determined. Staining was also quantified and analyzed. Bacterial viability was determined by culture turbidity and growth on agar plates. Preincubation of Chang and human corneal limbal epithelial cells with AZM, ERY, and TET at ≥64 μg/ml provided protection against AZM-susceptible S. aureus strains, with increasing protection at higher concentrations. TET toxicity was demonstrated at >64 μg/ml, whereas AZM displayed toxicity to one cell line at 512 μg/ml. BAC failed to show consistent protection at any dose, despite bacterial susceptibility to BAC as determined by traditional antibiotic susceptibility testing. A range of antibiotic effectiveness was displayed in this cell association assay, providing data that may be considered in addition to traditional testing when determining therapeutic dosing regimens. PMID:21628536

  1. Bim expression in endothelial cells and pericytes is essential for regression of the fetal ocular vasculature.

    PubMed

    Wang, Shoujian; Zaitoun, Ismail S; Johnson, Ryan P; Jamali, Nasim; Gurel, Zafer; Wintheiser, Catherine M; Strasser, Andreas; Lindner, Volkhard; Sheibani, Nader; Sorenson, Christine M

    2017-01-01

    Apoptosis plays a central role in developmental and pathological angiogenesis and vessel regression. Bim is a pro-apoptotic Bcl-2 family member that plays a prominent role in both developmental and pathological ocular vessel regression, and neovascularization. Endothelial cells (EC) and pericytes (PC) each play unique roles during vascular development, maintenance and regression. We recently showed that germline deletion of Bim results in persistent hyaloid vasculature, increased retinal vascular density and prevents retinal vessel regression in response to hyperoxia. To determine whether retinal vascular regression is attributable to Bim expression in EC or PC we generated mice carrying a conditional Bim allele (BimFlox/Flox) and VE-cadherin-cre (BimEC mice) or Pdgfrb-cre (BimPC mice). BimEC and BimPC mice demonstrated attenuated hyaloid vessel regression and postnatal retinal vascular remodeling. We also observed decreased retinal vascular apoptosis and proliferation. Unlike global Bim -/- mice, mice conditionally lacking Bim in EC or PC underwent hyperoxia-mediated vessel obliteration and subsequent retinal neovascularization during oxygen-induced ischemic retinopathy similar to control littermates. Thus, understanding the cell autonomous role Bim plays in the retinal vascular homeostasis will give us new insight into how to modulate pathological retinal neovascularization and vessel regression to preserve vision.

  2. Differential Expression of Stem Cell Markers in Ocular Surface Squamous Neoplasia

    PubMed Central

    Mishra, Dilip Kumar; Veena, Uppala; Kaliki, Swathi; Kethiri, Abhinav Reddy; Sangwan, Virender S.; Ali, Mohammed Hasnat; Naik, Milind N.; Singh, Vivek

    2016-01-01

    Ocular Surface Squamous Neoplasm (OSSN) is the neoplasia arising from the conjunctiva, cornea and limbus. OSSN ranges from mild, moderate, severe dysplasia, carcinoma in situ (CIS) to squamous cell carcinoma (SCC). Recent findings on cancer stem cells theory indicate that population of stem-like cell as in neoplasia determines its heterogeneity and complexity leading to varying tumor development of metastatic behavior and recurrence. Cancer stem cell markers are not much explored in the cases of OSSN. In the present study, we aim to evaluate the expression of stem cells using stem cell markers mainly p63, ABCG2, c-KIT (CD117) and CD44 in OSSN tissue, which could have prognostic significance. The present study tries for the first time to explore expression of these stem markers in the cases of OSSN. These cases are subdivided into two groups. One group comprises of carcinoma in situ (n = 6) and the second group comprises of invasive carcinoma (n = 6). The mean age at presentation was 52 years; with 53 years for CIS group and 52 years for SCC group. From each group section from the paraffin block were taken for the IHC staining of p63, c-Kit, ABCG2 and CD44. Our experiments show high expression of P63 and CD44 in the cases of CIN and SCC. Both CIS and SCC displayed positive staining with p63, with more than 80% cells staining positive. However minimal expression of c-kit in both CIN and SCC. But surprisingly we got high expression of ABCG2 in cases of carcinoma in situ as compared to that of invasive squamous cell carcinoma. More than 50% of cells showed CD44 positivity in both CIS and SCC groups. Our results show for the first time that these four stem cells especially the limbal epithelium stem cells play a vital role in the genesis of OSSN but we need to explore more cases before establishing its clinical and biological significance. PMID:27584160

  3. Pathogenesis, Transmissibility, and Ocular Tropism of a Highly Pathogenic Avian Influenza A (H7N3) Virus Associated with Human Conjunctivitis

    PubMed Central

    Belser, Jessica A.; Davis, C. Todd; Balish, Amanda; Edwards, Lindsay E.; Zeng, Hui; Maines, Taronna R.; Gustin, Kortney M.; Martínez, Irma López; Fasce, Rodrigo; Cox, Nancy J.; Katz, Jacqueline M.

    2013-01-01

    H7 subtype influenza A viruses, responsible for numerous outbreaks in land-based poultry in Europe and the Americas, have caused over 100 cases of confirmed or presumed human infection over the last decade. The emergence of a highly pathogenic avian influenza H7N3 virus in poultry throughout the state of Jalisco, Mexico, resulting in two cases of human infection, prompted us to examine the virulence of this virus (A/Mexico/InDRE7218/2012 [MX/7218]) and related avian H7 subtype viruses in mouse and ferret models. Several high- and low-pathogenicity H7N3 and H7N9 viruses replicated efficiently in the respiratory tract of mice without prior adaptation following intranasal inoculation, but only MX/7218 virus caused lethal disease in this species. H7N3 and H7N9 viruses were also detected in the mouse eye following ocular inoculation. Virus from both H7N3 and H7N9 subtypes replicated efficiently in the upper and lower respiratory tracts of ferrets; however, only MX/7218 virus infection caused clinical signs and symptoms and was capable of transmission to naive ferrets in a direct-contact model. Similar to other highly pathogenic H7 viruses, MX/7218 replicated to high titers in human bronchial epithelial cells, yet it downregulated numerous genes related to NF-κB-mediated signaling transduction. These findings indicate that the recently isolated North American lineage H7 subtype virus associated with human conjunctivitis is capable of causing severe disease in mice and spreading to naive-contact ferrets, while concurrently retaining the ability to replicate within ocular tissue and allowing the eye to serve as a portal of entry. PMID:23487452

  4. Effect of aging on the human initial interaural linear vestibulo-ocular reflex.

    PubMed

    Tian, Jun-Ru; Crane, Benjamin T; Wiest, Gerald; Demer, Joseph L

    2002-07-01

    To determine age-related changes, the initial linear vestibulo-ocular reflex (LVOR) of eight older subjects of mean age 65+/-7 years (mean +/- SD, range 56-75 years) was compared with that of nine younger subjects of mean age 24+/-5 years (range 18-31 years) in response to random transients of whole-body heave (interaural) translation at peak acceleration of 0.5 g delivered by a pneumatic actuator. Binocular eye rotations were measured with magnetic search coils, while linear head position and acceleration were measured with a potentiometer and piezoelectric accelerometer. Subjects viewed targets 200 cm, 50 cm, or 15 cm distant immediately before the unpredictable onset of randomly directed translation in darkness (LVOR) and in light (LVVOR). All subjects maintained ideal vergence of 1.5-2 degrees for the 200-cm target, 6-8 degrees for the 50-cm target, and 21-26 degrees for the 15-cm target, with actual vergences depending on individual interpupillary distances. Search coil recording of angular position of the upper teeth showed head rotation to be negligible (less than 0.5 degrees ) for the first 250 ms after onset of head translation, excluding a role for the angular VOR in the responses studied. The LVOR response to heave translation was an oppositely directed eye rotation occurring after a mean latency of 62+/-3 ms for older and 42+/-3 ms (mean +/- SD) for younger subjects ( P<0.0001). The peak of the latency distribution was 60-100 ms for older and 20-60 ms for younger subjects. During the early interval, 70-80 ms from head motion onset prior to a pursuit contribution or saccades, all subjects had significantly enhanced LVOR with decreasing target distance. In this interval, the LVOR position amplitude of younger subjects was 0.17+/-0.01 degrees, 0.40+/-0.01 degrees, 0.57+/-0.01 degrees (mean +/- SE), respectively, in descending order of target distance. Early sensitivities were significantly reduced for older subjects to 0.07+/-0.01 degrees, 0

  5. A linear canal-otolith interaction model to describe the human vestibulo-ocular reflex.

    PubMed

    Crane, B T; Demer, J L

    1999-08-01

    A control systems model of the vestibulo-ocular reflex (VOR) originally derived for yaw rotation about an eccentric axis (Crane et al. 1997) was applied to data collected during ambulation and dynamic posturography. The model incorporates a linear summation of an otolith response due to head translation scaled by target distance, adding to a semi-circular canal response that depends only on angular head rotation. The results of the model were compared with human experimental data by supplying head angular velocity as determined by magnetic search coil recording as the input for the canal branch of the model and supplying linear acceleration as determined by flux gate magnetometer measurements of otolith position. The model was fit to data by determining otolith weighting that enabled the model to best fit the data. We fit to the model experimental data from normal subjects who were: standing quietly, walking, running, or making active sinusoidal head movements. We also fit data obtained during dynamic posturography tasks of: standing on a platform sliding in a horizontal plane at 0.2 Hz, standing directly on a platform tilting at 0.1 Hz, and standing on the tilting platform buffered by a 5-cm thick foam rubber cushion. Each task was done with the subject attending a target approximately 500, 100, or 50 cm distant, both in light and darkness. The model accurately predicted the observed VOR response during each test. Greater otolith weighting was required for near targets for nearly all activities, consistent with weights for the otolith component found in previous studies employing imposed rotations. The only exceptions were for vertical axis motion during standing, sliding, and tilting when the platform was buffered with foam rubber. In the horizontal axis, the model always fit near target data better with a higher otolith component. Otolith weights were similar with the target visible and in darkness. The model predicts eye movement during both passive whole

  6. Plasticity of the human vestibulo-ocular reflex during off-vertical axis rotation.

    PubMed

    Akutsu, Masatoshi; Sugita-Kitajima, Akemi; Mikami, Koshi; Koizuka, Izumi

    2016-08-01

    We investigated whether adaptive plasticity of the vestibulo-ocular reflex in humans occurs in response to visual-vestibular conflict stimulation during rotation about a 30° incline (off-vertical earth axis rotation, OVAR). Subjects were 26 healthy adults (17 males and 9 females), ranging in age from 22 to 33 years (mean: 24.4) with no history of neurotological symptoms. Each testing session consisted of a pre-test, an adaptation period, and a post-test. The pre-test and the post-test were performed in complete darkness with the subjects' eyes opened. Subjects were rotated sinusoidally at 0.16Hz under OVAR, with a maximum angular velocity of 60°/s for 30s. Subjects were divided into two groups depending on the kind of visual stimulation. One group of subjects was rotated sinusoidally at 0.16Hz and 60°/s peak velocity under OVAR for 20min while viewing optokinetic stripes, which moved at the same frequency and peak velocity as the rotational chair but in the opposite direction (X2 adaptation paradigm). The other group of subjects was rotated sinusoidally at 0.16Hz and 60°/s peak velocity under OVAR for 20min while viewing optokinetic stripes, which moved at the same frequency and peak velocity as the rotatory chair but in the same direction (X0 adaptation paradigm). There was no significant difference in gain before or after adaptation using the X2 adaptation paradigm. VOR gain decreased significantly after adaptation using the X0 adaptation paradigm. We hypothesize that attenuation of VOR gain increase after the X2 adaptation paradigm is caused by tilt suppression. In the X0 adaptation paradigm, the decrease in VOR gain was facilitated by tilt suppression in addition to the plastic change of the VOR gain caused by visual-vestibular conflict stimulation. Consequently, the VOR gain change ratio in the X0 adaptation paradigm increased significantly compared to that in the X2 adaptation paradigm. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  7. Methylprednisolone fails to preserve retinal ganglion cells and visual function after ocular ischemia in rats.

    PubMed

    Dimitriu, Cornelia; Bach, Michael; Lagrèze, Wolf A; Jehle, Thomas

    2008-11-01

    Methylprednisolone (MP) is commonly used to treat traumatic optic neuropathy and optic neuritis, but its benefit in terms of neuronal survival remains controversial. The aim of this study was to investigate the effects of MP on retinal ganglion cell (RGC) survival and visual function after ischemia in rats. Ocular ischemia was induced by elevated intraocular pressure. Rats were treated with NaCl, 1 mg/kg/d, or 30 mg/kg/d intraperitoneal MP over 3 days. RGCs were labeled retrogradely 4 days after ischemia and were quantified 6 days later. Post-ischemic retinal function was assessed by scotopic and photopic electroretinography (ERG). Optic nerve function was investigated on days 4 and 10 after ischemia by visual evoked potentials (VEPs). Compared with nonischemic eyes, ischemia reduced RGCs with NaCl to 47% +/- 3% (mean +/- SEM) and to 46% +/- 3% and 43% +/- 6% with 1 mg/kg/d and 30 mg/kg/d MP. ERG did not differ significantly for any parameter among the three groups. Four days after ischemia, the VEPs of rats receiving any dose of MP were significantly higher than the control. VEPs in both steroid groups fell to control levels 10 days after ischemia. Treatment with MP did not improve RGC survival or retinal function. The VEP showed a short-term benefit because of steroids.

  8. Ocular neuropathy in peripheral neuropathies.

    PubMed

    Evliyaoglu, Ferhat; Karadag, Remzi; Burakgazi, Ahmet Z

    2012-11-01

    Ocular movements and coordination require complex and integrated functions of somatic and autonomic nervous systems. Neurological disorders affecting these nervous systems may cause ocular dysfunction involving extraocular muscles and pupils. In this article, the prevalence, clinical presentations, and management of ocular neuropathy related to certain peripheral neuropathies, including diabetic neuropathy, Guillain-Barré syndrome (GBS), chronic inflammatory neuropathies, human immunodeficiency virus (HIV)-associated neuropathy, and hereditary neuropathies, are examined in detail. Copyright © 2012 Wiley Periodicals, Inc.

  9. Aerobic Exercise Effects on Ocular Dominance Plasticity with a Phase Combination Task in Human Adults.

    PubMed

    Zhou, Jiawei; Reynaud, Alexandre; Hess, Robert F

    2017-01-01

    Several studies have shown that short-term monocular patching can induce ocular dominance plasticity in normal adults, in which the patched eye becomes stronger in binocular viewing. There is a recent study showing that exercise enhances this plasticity effect when assessed with binocular rivalry. We address one question, is this enhancement from exercise a general effect such that it is seen for measures of binocular processing other than that revealed using binocular rivalry? Using a binocular phase combination task in which we directly measure each eye's contribution to the binocularly fused percept, we show no additional effect of exercise after short-term monocular occlusion and argue that the enhancement of ocular dominance plasticity from exercise could not be demonstrated with our approach.

  10. Aerobic Exercise Effects on Ocular Dominance Plasticity with a Phase Combination Task in Human Adults

    PubMed Central

    Reynaud, Alexandre; Hess, Robert F.

    2017-01-01

    Several studies have shown that short-term monocular patching can induce ocular dominance plasticity in normal adults, in which the patched eye becomes stronger in binocular viewing. There is a recent study showing that exercise enhances this plasticity effect when assessed with binocular rivalry. We address one question, is this enhancement from exercise a general effect such that it is seen for measures of binocular processing other than that revealed using binocular rivalry? Using a binocular phase combination task in which we directly measure each eye's contribution to the binocularly fused percept, we show no additional effect of exercise after short-term monocular occlusion and argue that the enhancement of ocular dominance plasticity from exercise could not be demonstrated with our approach. PMID:28357142

  11. HLA-A02:01-restricted epitopes identified from the herpes simplex virus tegument protein VP11/12 preferentially recall polyfunctional effector memory CD8+ T cells from seropositive asymptomatic individuals and protect humanized HLA-A*02:01 transgenic mice against ocular herpes.

    PubMed

    Srivastava, Ruchi; Khan, Arif A; Spencer, Doran; Vahed, Hawa; Lopes, Patricia P; Thai, Nhi Thi Uyen; Wang, Christine; Pham, Thanh T; Huang, Jiawei; Scarfone, Vanessa M; Nesburn, Anthony B; Wechsler, Steven L; BenMohamed, Lbachir

    2015-03-01

    The HSV type 1 tegument virion phosphoprotein (VP) 11/12 (VP11/12) is a major Ag targeted by CD8(+) T cells from HSV-seropositive individuals. However, whether and which VP11/12 epitope-specific CD8(+) T cells play a role in the "natural" protection seen in seropositive healthy asymptomatic (ASYMP) individuals (who have never had clinical herpes disease) remain to be determined. In this study, we used multiple prediction computer-assisted algorithms to identify 10 potential HLA-A*02:01-restricted CD8(+) T cell epitopes from the 718-aa sequence of VP11/12. Three of 10 epitopes exhibited high-to-moderate binding affinity to HLA-A*02:01 molecules. In 10 sequentially studied HLA-A*02:01-positive and HSV-1-seropositive ASYMP individuals, the most frequent, robust, and polyfunctional effector CD8(+) T cell responses, as assessed by a combination of tetramer frequency, granzyme B, granzyme K, perforin, CD107(a/b) cytotoxic degranulation, IFN-γ, and multiplex cytokines assays, were predominantly directed against three epitopes: VP11/1266-74, VP11/12220-228, and VP11/12702-710. Interestingly, ASYMP individuals had a significantly higher proportion of CD45RA(low)CCR7(low)CD44(high)CD62L(low)CD27(low)CD28(low)CD8(+) effector memory CD8(+) T cells (TEMs) specific to the three epitopes, compared with symptomatic individuals (with a history of numerous episodes of recurrent ocular herpetic disease). Moreover, immunization of HLA-A*02:01 transgenic mice with the three ASYMP CD8(+) TEM cell epitopes induced robust and polyfunctional epitope-specific CD8(+) TEM cells that were associated with a strong protective immunity against ocular herpes infection and disease. Our findings outline phenotypic and functional features of protective HSV-specific CD8(+) T cells that should guide the development of an effective T cell-based herpes vaccine. Copyright © 2015 by The American Association of Immunologists, Inc.

  12. Human memory B cells.

    PubMed

    Seifert, M; Küppers, R

    2016-12-01

    A key feature of the adaptive immune system is the generation of memory B and T cells and long-lived plasma cells, providing protective immunity against recurring infectious agents. Memory B cells are generated in germinal center (GC) reactions in the course of T cell-dependent immune responses and are distinguished from naive B cells by an increased lifespan, faster and stronger response to stimulation and expression of somatically mutated and affinity matured immunoglobulin (Ig) genes. Approximately 40% of human B cells in adults are memory B cells, and several subsets were identified. Besides IgG(+) and IgA(+) memory B cells, ∼50% of peripheral blood memory B cells express IgM with or without IgD. Further smaller subpopulations have additionally been described. These various subsets share typical memory B cell features, but likely also fulfill distinct functions. IgM memory B cells appear to have the propensity for refined adaptation upon restimulation in additional GC reactions, whereas reactivated IgG B cells rather differentiate directly into plasma cells. The human memory B-cell pool is characterized by (sometimes amazingly large) clonal expansions, often showing extensive intraclonal IgV gene diversity. Moreover, memory B-cell clones are frequently composed of members of various subsets, showing that from a single GC B-cell clone a variety of memory B cells with distinct functions is generated. Thus, the human memory B-cell compartment is highly diverse and flexible. Several B-cell malignancies display features suggesting a derivation from memory B cells. This includes a subset of chronic lymphocytic leukemia, hairy cell leukemia and marginal zone lymphomas. The exposure of memory B cells to oncogenic events during their generation in the GC, the longevity of these B cells and the ease to activate them may be key determinants for their malignant transformation.

  13. A comparative evaluation of corneal epithelial cell cultures for assessing ocular permeability.

    PubMed

    Becker, Ulrich; Ehrhardt, Carsten; Schneider, Marc; Muys, Leon; Gross, Dorothea; Eschmann, Klaus; Schaefer, Ulrich F; Lehr, Claus-Michael

    2008-02-01

    The purpose of this study was to evaluate the potential value of different epithelial cell culture systems as in vitro models for studying corneal permeability. Transformed human corneal epithelial (HCE-T) cells and Statens Serum Institut rabbit corneal (SIRC) cells were cultured on permeable filters. SkinEthic human corneal epithelium (S-HCE) and Clonetics human corneal epithelium (C-HCE) were received as ready-to-use systems. Excised rabbit corneas (ERCs) and human corneas (EHCs) were mounted in Ussing chambers, and used as references. Barrier properties were assessed by measuring transepithelial electrical resistance, and by determining the apparent permeability of markers with different physico-chemical properties, namely, fluorescein, sodium salt; propranolol hydrochloride; moxaverine hydrochloride; timolol hydrogenmaleate; and rhodamine 123. SIRC cells and the S-HCE failed to develop epithelial barrier properties, and hence were unable to distinguish between the permeation markers. Barrier function and the power to differentiate compound permeabilities were evident with HCE-T cells, and were even more pronounced in the case of C-HCE, corresponding very well with data from ERCs and EHCs. A net secretion of rhodamine 123 was not observed with any of the models, suggesting that P-glycoprotein or similar efflux systems have no significant effects on corneal permeability. Currently available corneal epithelial cell culture systems show differences in epithelial barrier function. Systems lacking functional cell-cell contacts are of limited value for assessing corneal permeability, and should be critically evaluated for other purposes.

  14. Treatment of ocular disorders by gene therapy.

    PubMed

    Solinís, M Ángeles; del Pozo-Rodríguez, Ana; Apaolaza, Paola S; Rodríguez-Gascón, Alicia

    2015-09-01

    Gene therapy to treat ocular disorders is still starting, and current therapies are primarily experimental, with most human clinical trials still in research state, although beginning to show encouraging results. Currently 33 clinical trials have been approved, are in progress, or have been completed. The most promising results have been obtained in clinical trials of ocular gene therapy for Leber Congenital Amaurosis, which have prompted the study of several ocular diseases that are good candidates to be treated with gene therapy: glaucoma, age-related macular degeneration, retinitis pigmentosa, or choroideremia. The success of gene therapy relies on the efficient delivery of the genetic material to target cells, achieving optimum long-term gene expression. Although viral vectors have been widely used, their potential risk associated mainly with immunogenicity and mutagenesis has promoted the design of non-viral vectors. In this review, the main administration routes and the most studied delivery systems, viral and non-viral, for ocular gene therapy are presented. The primary ocular disease candidates to be treated with gene therapy have been also reviewed, including the genetic basis and the most relevant preclinical and clinical studies.

  15. Ocular Sarcoidosis

    PubMed Central

    Pasadhika, Sirichai; Rosenbaum, James T

    2015-01-01

    Sarcoidosis is one of the leading causes of inflammatory eye disease. Ocular sarcoidosis can involve any part of the eye and its adnexal tissues, and may cause uveitis, episcleritis/scleritis, eyelid abnormalities, conjunctival granuloma, optic neuropathy, lacrimal gland enlargement and orbital inflammation. Glaucoma and cataract can be complications from inflammation itself or adverse effects from therapy. Ophthalmic manifestations can be isolated, or associated with other organ involvement. Patients with ocular sarcoidosis can present with a wide range of clinical presentations and severity. Multi-disciplinary approaches are required to achieve the best treatment outcomes for both ocular and systemic manifestations. PMID:26593141

  16. Selective Vulnerability of Specific Retinal Ganglion Cell Types and Synapses after Transient Ocular Hypertension

    PubMed Central

    Jo, Rebecca E.; Ullian, Erik M.; Wong, Rachel O.L.

    2016-01-01

    Key issues concerning ganglion cell type-specific loss and synaptic changes in animal models of experimental glaucoma remain highly debated. Importantly, changes in the structure and function of various RGC types that occur early, within 14 d after acute, transient intraocular pressure elevation, have not been previously assessed. Using biolistic transfection of individual RGCs and multielectrode array recordings to measure light responses in mice, we examined the effects of laser-induced ocular hypertension on the structure and function of a subset of RGCs. Among the α-like RGCs studied, αOFF-transient RGCs exhibited higher rates of cell death, with corresponding reductions in dendritic area, dendritic complexity, and synapse density. Functionally, OFF-transient RGCs displayed decreases in spontaneous activity and receptive field size. In contrast, neither αOFF-sustained nor αON-sustained RGCs displayed decreases in light responses, although they did exhibit a decrease in excitatory postsynaptic sites, suggesting that synapse loss may be one of the earliest signs of degeneration. Interestingly, presynaptic ribbon density decreased to a greater degree in the OFF sublamina of the inner plexiform layer, corroborating the hypothesis that RGCs with dendrites stratifying in the OFF sublamina may be damaged early. Indeed, OFF arbors of ON-OFF RGCs lose complexity more rapidly than ON arbors. Our results reveal type-specific differences in RGC responses to injury with a selective vulnerability of αOFF-transient RGCs, and furthermore, an increased susceptibility of synapses in the OFF sublamina. The selective vulnerability of specific RGC types offers new avenues for the design of more sensitive functional tests and targeted neuroprotection. SIGNIFICANCE STATEMENT Conflicting reports regarding the selective vulnerability of specific retinal ganglion cell (RGC) types in glaucoma exist. We examine, for the first time, the effects of transient intraocular pressure

  17. Ocular hypertension impairs optic nerve axonal transport leading to progressive retinal ganglion cell degeneration.

    PubMed

    Salinas-Navarro, Manuel; Alarcón-Martínez, Luis; Valiente-Soriano, Francisco J; Jiménez-López, Manuel; Mayor-Torroglosa, Sergio; Avilés-Trigueros, Marcelino; Villegas-Pérez, María Paz; Vidal-Sanz, Manuel

    2010-01-01

    Ocular hypertension (OHT) is the main risk factor of glaucoma, a neuropathy leading to blindness. Here we have investigated the effects of laser photocoagulation (LP)-induced OHT, on the survival and retrograde axonal transport (RAT) of adult rat retinal ganglion cells (RGC) from 1 to 12 wks. Active RAT was examined with fluorogold (FG) applied to both superior colliculi (SCi) 1 wk before processing and passive axonal diffusion with dextran tetramethylrhodamine (DTMR) applied to the optic nerve (ON) 2 d prior to sacrifice. Surviving RGCs were identified with FG applied 1 wk pre-LP or by Brn3a immunodetection. The ON and retinal nerve fiber layer were examined by RT97-neurofibrillar staining. RGCs were counted automatically and color-coded density maps were generated. OHT retinas showed absence of FG+ or DTMR+RGCs in focal, pie-shaped and diffuse regions of the retina which, by two weeks, amounted to, approximately, an 80% of RGC loss without further increase. At this time, there was a discrepancy between the total number of surviving FG-prelabelled RGCs and of DMTR+RGCs, suggesting that a large proportion of RGCs had their RAT impaired. This was further confirmed identifying surviving RGCs by their Brn3a expression. From 3 weeks onwards, there was a close correspondence of DTMR+RGCs and FG+RGCs in the same retinal regions, suggesting axonal constriction at the ON head. Neurofibrillar staining revealed, in ONs, focal degeneration of axonal bundles and, in the retinal areas lacking backlabeled RGCs, aberrant staining of RT97 characteristic of axotomy. LP-induced OHT results in a crush-like injury to ON axons leading to the anterograde and protracted retrograde degeneration of the intraocular axons and RGCs.

  18. Ocular pulse amplitude as a diagnostic adjunct in giant cell arteritis

    PubMed Central

    Knecht, P B; Bachmann, L M; Thiel, M A; Landau, K; Kaufmann, C

    2015-01-01

    Background To develop an algorithm based on the ocular pulse amplitude (OPA) to predict the probability of a positive temporal artery biopsy (TAB) result in the acute phase of suspected giant cell arteritis (GCA). Methods Unilateral TAB was performed and ipsilateral OPA measurements were taken by Dynamic Contour Tonometry. Among the clinical signs and laboratory findings tested in univariate analyses, OPA, Erythrocyte Sedimentation Rate (ESR) and thrombocyte count showed a strong association with a positive TAB result. Algorithm parameters were categorized into three groups (OPA >3.5, 2.5–3.5, and <2.5 mm Hg; ESR <25, 25–60, and >60 mm/h; thrombocyte count <250'000, 250'000–500'000, and >500'000/μl). Score values (0, 1, and 2) were attributed to each group, resulting in a total score range from 0 to 6. A univariate logistic regression analysis using the GCA diagnosis as the dependent and the total score as the independent variate was fitted and probability estimates were calculated. Results Thirty-one patients with suspected GCA undergoing TAB during an eighteen-month observation period were enrolled. Twenty patients showed histologically proven GCA. Four patients had score values ≤2, fourteen between 3 and 4, and thirteen of ≥5. The corresponding estimated probabilities of GCA were<7, 52.6, and >95%. Conclusion The present study confirms previous findings of reduced OPA levels, elevated ESR, and elevated thrombocyte counts in GCA. It indicates that a sum score based on OPA, ESR, and thrombocyte count can be helpful in predicting TAB results, especially at the upper and the lower end of the sum score range. PMID:26088675

  19. Ocular Reflex Phase during Off-Vertical Axis Rotation in Humans is Modified by Head-Turn-On-Trunk Position

    PubMed Central

    Douglas, Samantha B.; Clément, Gilles; Denise, Pierre; Wood, Scott J.

    2017-01-01

    Constant velocity Off-Vertical Axis Rotation (OVAR) imposes a continuously varying orientation of the head and body relative to gravity, which generates a modulation of horizontal (conjugate and vergence), vertical, and torsional eye movements. We introduced the head-turn-on-trunk paradigm during OVAR to examine the extent to whether the modulation of these ocular reflexes is mediated by graviceptors in the head, i.e., otoliths, versus other body graviceptors. Ten human subjects were rotated in darkness about their longitudinal axis 20° off-vertical at a constant velocity of 45 and 180°/s, corresponding to 0.125 and 0.5 Hz. Binocular responses were obtained with the head and trunk aligned, and then with the head turned relative to the trunk 40° to the right or left of center. The modulation of vertical and torsional eye position was greater at 0.125 Hz while the modulation of horizontal and vergence slow phase velocity was greater at 0.5 Hz. The amplitude modulation was not significantly altered by head-on-trunk position, but the phases shifted towards alignment with the head. These results are consistent with the modulation of ocular reflexes during OVAR being primarily mediated by the otoliths in response to the sinusoidally varying linear acceleration along the interaural and naso-occipital head axis. PMID:28176802

  20. Hydrogels for ocular drug delivery and tissue engineering

    PubMed Central

    Fathi, Marzieh; Barar, Jaleh; Aghanejad, Ayuob; Omidi, Yadollah

    2015-01-01

    Hydrogels, as crosslinked polymeric three dimensional networks, possess unique structure and behavior in response to the internal and/or external stimuli. As a result, they offer great prospective applications in drug delivery, cell therapy and human tissue engineering. Here, we highlight the potential of hydrogels in prolonged intraocular drug delivery and ocular surface therapy using stem cells incorporated hydrogels. PMID:26929918

  1. Melatonin and Sleep-Wake Rhythms before and after Ocular Lens Replacement in Elderly Humans

    PubMed Central

    Giménez, Marina; Beersma, Domien; Daan, Serge; van der Pol, Bert; Kanis, Martijn; van Norren, Dick; Gordijn, Marijke

    2016-01-01

    Light of short wavelengths has been shown to play a key role in non-image forming responses. Due to aging, the ocular lens becomes more yellow reducing the transmission of short wavelengths in the elderly. In the present study, we make use of cataract surgery to investigate the effects of a relative increase of short wavelength transmission on melatonin- and sleep-wake rhythms (N = 14). We observed, on average, a delay of the sleep-wake and the nocturnal melatonin rhythms after cataract surgery. This delay is tentatively attributed to a relatively large increase of light transmittance in the evening hours more than an increase of the already relatively high light intensities found in the daytime. The later phase that we observed after cataract surgery (clear lens) as compared to the earlier phase observed before cataract (yellowish lens) is in agreement with the general later phase reported in the young (clear lens) population. PMID:26891336

  2. Parasitic diseases of zoonotic importance in humans of northeast India, with special reference to ocular involvement

    PubMed Central

    Das, Dipankar; Islam, Saidul; Bhattacharjee, Harsha; Deka, Angshuman; Yambem, Dinakumar; Tahiliani, Prerana Sushil; Deka, Panna; Bhattacharyya, Pankaj; Deka, Satyen; Das, Kalyan; Bharali, Gayatri; Deka, Apurba; Paul, Rajashree

    2014-01-01

    Parasitic zoonotic diseases are prevalent in India, including the northeastern states. Proper epidemiological data are lacking from this part of the country on zoonotic parasitic diseases, and newer diseases are emerging in the current scenario. Systemic manifestation of such diseases as cysticercosis, paragonimiasis, hydatidosis, and toxoplasmosis are fairly common. The incidence of acquired toxoplasmal infection is showing an increasing trend in association with acquired immunodeficiency syndrome. Among the ocular parasitic diseases, toxoplasmosis, cysticercosis, toxocariasis, dirofilariasis, gnathostomiasis, hydatidosis, amebiasis, giardiasis, etc, are the real problems that are seen in this subset of the population. Therefore, proper coordination between various medical specialities, including veterinary science and other governing bodies, is needed for better and more effective strategic planning to control zoonoses. PMID:28539786

  3. Melatonin and Sleep-Wake Rhythms before and after Ocular Lens Replacement in Elderly Humans.

    PubMed

    Giménez, Marina; Beersma, Domien; Daan, Serge; Pol, Bert van der; Kanis, Martijn; van Norren, Dick; Gordijn, Marijke

    2016-02-15

    Light of short wavelengths has been shown to play a key role in non-image forming responses. Due to aging, the ocular lens becomes more yellow reducing the transmission of short wavelengths in the elderly. In the present study, we make use of cataract surgery to investigate the effects of a relative increase of short wavelength transmission on melatonin- and sleep-wake rhythms (N = 14). We observed, on average, a delay of the sleep-wake and the nocturnal melatonin rhythms after cataract surgery. This delay is tentatively attributed to a relatively large increase of light transmittance in the evening hours more than an increase of the already relatively high light intensities found in the daytime. The later phase that we observed after cataract surgery (clear lens) as compared to the earlier phase observed before cataract (yellowish lens) is in agreement with the general later phase reported in the young (clear lens) population.

  4. Medial medullary infarction: abnormal ocular motor findings.

    PubMed

    Kim, J Soo; Choi, K-D; Oh, S-Y; Park, S-H; Han, M-K; Yoon, B-W; Roh, J-K

    2005-10-25

    In 20 consecutive patients with isolated medial medullary infarction, abnormal ocular motor findings included nystagmus (n = 8), ocular contrapulsion (n = 5), and contralesional ocular tilt reaction (n = 2). The nystagmus was ipsilesional (n = 4), gaze-evoked (n = 5), upbeating (n = 4), and hemiseesaw (n = 1). The ocular motor abnormalities may be explained by involvements of the nucleus prepositus hypoglossi, medial longitudinal fasciculus or efferent fibers from the vestibular nuclei, climbing fibers, and cells of the paramedian tracts.

  5. A modified chronic ocular hypertension rat model for retinal ganglion cell neuroprotection.

    PubMed

    Zhong, Lichun

    2013-09-01

    This study aimed to modify a chronic ocular hypertension (OHT) rat model to screen for potential compounds to protect retinal ganglion cells (RGCs) from responding to increased intraocular pressure (IOP). A total of 266 rats were prepared and randomly grouped according to different time-points, namely, weeks 3, 8, 16, and 24. Rats were sedated and eye examination was performed to score as the corneal damage on a scale of 1 to 4. The OHT rat model was created via the injection of a hypertonic saline solution into the episcleral veins once weekly for two weeks. OHT was identified when the IOP at week 0 was [Symbol: see text] 6 mmHg than that at week -2 for the same eye. Viable RGCs were labeled by injecting 4% FluoroGold. Rats were sacrificed, and the eyes were enucleated and fixed. The fixed retinas were dissected to prepare flat whole-mounts. The viable RGCs were visualized and imaged. The IOP (mean ± SD) was calculated, and data were analyzed by the paired t-test and one-way ANOVA. The OHT model was created in 234 of 266 rats (87.97%), whereas 32 rats (12.03%) were removed from the study because of the absence of IOP elevation (11.28%) and/or corneal damage scores over 4 (0.75%). IOP was elevated by as much as 81.35% for 24 weeks. The average IOP was (16.68 ± 0.98) mmHg in non-OHT eyes (n = 234), but was (27.95 ± 0.97) mmHg in OHTeyes (n = 234). Viable RGCs in the OHT eyes were significantly decreased in a time-dependent manner by 29.41%, 38.24%, 55.32%, and 59.30% at weeks 3, 8, 16, and 24, respectively, as compared to viable RGCs in the non-OHT eyes (P < 0.05). The OHT model was successfully created in 88% of the rats. The IOP in the OHT eyes was elevated by approximately 81% for 24 weeks. The number of viable RGCs was decreased by 59% of the rats in a time-dependent manner. The modified OHT model may provide an effective and reliable method for screening drugs to protect RGCs from glaucoma.

  6. Relationship between caffeine-induced ocular hypertension and ultrastructure changes of non-pigmented ciliary epithelial cells in rats.

    PubMed

    Kurata, K; Maeda, M; Nishida, E; Tsukuda, R; Suzuki, T; Ando, T; Tokuriki, M

    1997-12-01

    The purpose of this study was to morphologically assess a possible mechanism for caffeine-induced ocular hypertension. Taking into consideration the relationship between the secretion of aqueous humor and the ultrastructure of the ciliary body, the time course of the morphological features in the ciliary epithelium when caffeine was administered intravenously to male Wistar rats was investigated by electron-microscopy. These morphological findings were also compared with the changes in the intraocular pressure (IOP). A significant increase in IOP was noted 15 min and 1 hr after a single dosing of caffeine alone. This change disappeared in all animals within 2 hr after dosing. The IOP in the animals receiving caffeine and the beta-blocker befunolol, which lowers the IOP by inhibiting aqueous humor secretion, decreased significantly from 15 min after dosing, and this change persisted 2 hr after dosing. In electron-microscopy 15 min and/or 1 hr after dosing with caffeine, a slight dilatation in the lateral intercellular spaces near the basement membrane of the non-pigmented ciliary epithelium was observed and the interdigitations between the non-pigmented epithelial cells were intact. Reversal of these changes was observed 2 hr after dosing. On the other hand, the lateral intercellular spaces between the non-pigmented epithelial cells were markedly dilated and the interdigitations were disorganized following dosing with caffeine alone and in combination with befunolol. These results described here indicate that the intravenous administration of caffeine causes ocular hypertension and also changes in the non-pigmented ciliary epithelium, suggesting an enhancement of aqueous humor transportation. This paradigm in the rat is considered to be useful to further assess caffeine-induced ocular hypertension and for use as an animal model in glaucoma research associated with an aqueous humor secretion.

  7. Three-dimensional volume visualization of the in vivo human ocular lens showing localization of the cataract.

    PubMed

    Masters, B R; Sasaki, K; Sakamoto, Y; Kojima, M; Emori, Y; Senft, S L; Foster, M

    1996-01-01

    An in vivo human lens containing a cataract has been visualized by volume rendering a transformed series of 60 rotated Scheimpflug digital images. The data set was obtained by rotating the Scheimpflug camera about the optic axis of the lens in 3-degree increments. The set of 60 Scheimpflug digital images were mathematically transformed into a new data set in which the images are oriented perpendicular to the optic axis of the eye. The transformed set of optical sections were first aligned to correct for eye movements during the data collection process, then rendered into a three-dimensional volume reconstruction with volume-rendering computer graphics techniques. The viewpoint and the transparency of the volume rendered in vivo human lens were varied in order to observe volume opacities in various regions of the lens. To help visualize lens opacities, the intensity of light scattering was pseudocolor-coded as an integral part of the three-dimensional volume rendering. Three-dimensional, pseudocolored volume rendering of the in vivo human ocular lens represents a new technique to visualize in vivo human cataracts.

  8. Neurotransmitter Influence on Human Meibomian Gland Epithelial Cells

    PubMed Central

    Kam, Wendy R.

    2011-01-01

    Purpose. A striking characteristic of the human meibomian gland is its rich sensory, sympathetic, and parasympathetic innervation, yet the functional relevance of these nerve fibers remains unknown. Acting on the hypothesis that neurotransmitters are released in the vicinity of the gland, act on glandular receptors, and influence the production, secretion, and/or delivery of meibomian gland secretions to the ocular surface, the goal in this study was to begin to determine whether neurotransmitters influence the meibomian gland. Methods. Immortalized human meibomian gland epithelial (SLHMG) cells were examined for the presence of vasoactive intestinal peptide (VIP) and muscarinic acetylcholine (mACh) receptor transcripts and proteins. Cells were also exposed to VIP, carbachol, forskolin, and/or 3-isobutyl-1-methylxanthine (IBMX) to determine whether these agents, alone or in combination, modulate the adenylyl cyclase pathway, the accumulation of intracellular free calcium ([Ca2+]i), or cell proliferation. Results. Results demonstrate that SLHMG cells transcribe and translate VIP and mACh receptors; VIP, with either IBMX or forskolin, activates the adenylyl cyclase pathway, and the effect of VIP and forskolin together is synergistic; both VIP and carbachol increase intracellular [Ca2+] in SLHMG cells; and VIP with forskolin stimulates SLHMG cell proliferation. Conclusions. This study shows that parasympathetic neurotransmitters and their agonists influence the function of human meibomian gland epithelial cells. It remains to be determined whether this action alters the production, secretion, and/or delivery of meibum to the ocular surface. PMID:21969302

  9. Potential of the Bioflavonoids in the Prevention/Treatment of Ocular Disorders

    PubMed Central

    Majumdar, Soumyajit; Srirangam, Ramesh

    2015-01-01

    Objectives Flavonoids are a common group of plant polyphenols that give color and flavor to fruits and vegetables. In recent years, flavonoids have gained importance in the pharmaceutical field through their beneficial effects on human health and are widely available as nutritional supplements. Several pharmacological activities of the bioflavonoids may be useful in the prevention or treatment of ocular diseases responsible for vision loss such as diabetic retinopathy, macular degeneration, and cataract. This review summarizes potential therapeutic applications of various bioflavonoids in different ocular diseases and also discusses delivery of these agents to the ocular tissues. Key findings It is apparent that the flavonoids are capable of acting on various mecha- nisms or aetiological factors responsible for the development of different sight threatening ocular diseases. From a drug delivery perspective, ocular bioavailability depends on the physicochemical and biopharmaceutical characteristics of the selected flavonoids and very importantly the route of administration. Summary The potential therapeutic applications of various bioflavonoids in ocular dis- eases is reviewed and the delivery of these agents to the ocular tissues is discussed. Whereas oral administration of bioflavonoids may demonstrate some pharmacological activity in the outer sections of the posterior ocular segment, protection of the retinal ganglionic cells in vivo may be limited by this delivery route. Systemic or local administration of these agents may yield much higher and effective concentrations of the parent bioflavonoids in the ocular tissues and at much lower doses. PMID:20663029

  10. Rabies: ocular pathology.

    PubMed Central

    Haltia, M; Tarkkanen, A; Kivelä, T

    1989-01-01

    Ocular pathology in the first European case of human bat-borne rabies is described. The patient was a 30-year-old bat scientist who seven weeks after bat bite developed neurological symptoms and died 23 days later. Rabies virus antigens were detected in brain smears. After extensive virological studies the virus turned out to be a rabies-related virus, closely resembling the Duvenhage virus isolated from bats in South Africa in 1980. By light microscopy focal chronic inflammatory infiltration of the ciliary body and of the choroid was found. PAS-positive exudate was seen in the subretinal and in the outer plexiform layers of the retina, and retinal veins showed endothelial damage and perivascular inflammation. Many of the retinal ganglion cells were destroyed. The presence of rabies-related viral antigen in the retinal ganglion cells was shown by positive cytoplasmic immunofluorescence, though electron microscopy failed to identify definite viral structures in the retina. By immunohistochemistry glial fibrillary acidic protein was observed in the Müller's cells, which are normally negative for this antigen but express it as a reactive change when the retina is damaged. Synaptophysin, a constituent of presynaptic vesicles of normal retinal neurons, was not detected in the retina. Images PMID:2920157

  11. Cytotoxic effect of sodium hypochlorite 0.5% (NaOCl) on ocular melanoma cells in vitro.

    PubMed

    Missotten, G S; Keijser, S; de Keizer, R J W

    2008-01-01

    Excision with or without adjuvant cryotherapy or brachytherapy is the treatment of choice in conjunctival melanoma. Adjuvant rinsing with alcohol or sodium hypochlorite peroperatively (Dakin's solution) is used in some centers to prevent seeding of melanoma cells. The purpose of this research is to compare the cytotoxicity of sodium hypochlorite (NaOCl) with other potential cytotoxic solutions in the treatment of conjunctival melanoma. Three uveal melanoma cell lines (OCM8, Mel285, and Mel270) and one conjunctival melanoma cell line (CM2005.1) were tested in a proliferation test (CellTiter 96 AQueous One Solution Cell Proliferation Assay, Promega, Madison, WI). The 96-well plates were coated with melanoma cells and treated with sodium hypochlorite 0.5%, sodium bicarbonate (1.4% and 8.4%), ethanol 99%, or sodium chlorite during 3, 5, or 15 minutes. Each solution was tested in several dilutions. In all cell lines, no surviving cells were observed after treatment of 3 minutes with sodium hypochlorite. Ethanol 99% had a similar effect. A reduction of 70% of viable cells could be reached using sodium bicarbonate 1.4% or 8.4%. Water reduced the amount of viable cells by 40%. Sodium hypochlorite is cytotoxic for melanocytic cells in vitro. Its use may reduce local seeding of tumor cells and may decrease metastasis after extirpation of an extended ocular tumour. Further in vivo evaluation of sodium hypochlorite is required.

  12. Galectin-8 Ameliorates Murine Autoimmune Ocular Pathology and Promotes a Regulatory T Cell Response

    PubMed Central

    Sampson, James F.; Hasegawa, Eiichi; Mulki, Lama; Suryawanshi, Amol; Jiang, Shuhong; Chen, Wei-Sheng; Rabinovich, Gabriel A.; Connor, Kip M.; Panjwani, Noorjahan

    2015-01-01

    Galectins have emerged as potent immunoregulatory agents that control chronic inflammation through distinct mechanisms. Here, we report that treatment with Galectin-8 (Gal-8), a tandem-repeat member of the galectin family, reduces retinal pathology and prevents photoreceptor cell damage in a murine model of experimental autoimmune uveitis. Gal-8 treatment increased the number of regulatory T cells (Treg) in both the draining lymph node (dLN) and the inflamed retina. Moreover, a greater percentage of Treg cells in the dLN and retina of Gal-8 treated animals expressed the inhibitory coreceptor cytotoxic T lymphocyte antigen (CTLA)-4, the immunosuppressive cytokine IL-10, and the tissue-homing integrin CD103. Treg cells in the retina of Gal-8-treated mice were primarily inducible Treg cells that lack the expression of neuropilin-1. In addition, Gal-8 treatment blunted production of inflammatory cytokines by retinal T helper type (TH) 1 and TH17 cells. The effect of Gal-8 on T cell differentiation and/or function was specific for tissues undergoing an active immune response, as Gal-8 treatment had no effect on T cell populations in the spleen. Given the need for rational therapies for managing human uveitis, Gal-8 emerges as an attractive therapeutic candidate not only for treating retinal autoimmune diseases, but also for other TH1- and TH17-mediated inflammatory disorders. PMID:26126176

  13. Ocular toxocariasis.

    PubMed

    Arevalo, J Fernando; Espinoza, Juan V; Arevalo, Fernando A

    2013-01-01

    Ocular toxocariasis is an uncommon worldwide parasitic infection that affects mostly children and is found in both rural and metropolitan areas. In many parts of the world, parasitic infections of the eye are a major cause of blindness. The diagnosis of toxocariasis is essentially clinical, based on the lesion morphology and supportive laboratory data such as serum enzyme-linked immunosorbent assay (ELISA) titers and ELISA Toxocara titers on aqueous humor; other diagnostic methods are imaging studies including optical coherence tomography, fluorescein angiography, computed tomography, and ocular ultrasound. Treatment is directed at complications arising from intraocular inflammation and vitreous membrane traction. Early vitrectomy may be of value both diagnostically and therapeutically.

  14. Ocular Pathology.

    PubMed

    Bauer, Bianca S

    2015-08-01

    Although not comprehensive of all ocular conditions in the equine species, this article concentrates on various ophthalmic conditions observed in the horse where laboratory diagnostics are recommended. The importance of laboratory diagnostic testing cannot be underestimated with equine ophthalmic disease. In many cases, laboratory diagnostics can aid in obtaining an early diagnosis and determining appropriate therapy, which in turn, can provide a better prognosis. In unfortunate cases where ocular disease results in a blind, painful eye necessitating enucleation, light microscopic evaluation is imperative to determine or confirm the cause of the blindness and provide a prognosis for the contralateral eye.

  15. Ocular complications in HIV positive patients on antiretroviral therapy in Ghana.

    PubMed

    Martin-Odoom, Alexander; Bonney, Evelyn Yayra; Opoku, Derek Kofi

    2016-08-03

    Patients infected with human immunodeficiency virus (HIV) usually develop some form of ocular complication in the different segments of the eye due to immune deficiency. In Ghana, data regarding ocular complications among HIV/AIDS patients is scarce. This study investigated the occurrence of ocular complications in HIV infected patients undergoing antiretroviral therapy at the Agogo Presbyterian Hospital in the Ashanti Region of Ghana. Blood samples were taken from 100 confirmed HIV infected patients. The CD4 + T cell count and WHO clinical staging were determined. The patients were taken through thorough ophthalmic assessments to determine any ocular complications. Forty-eight patients (48 %) had at least one HIV-related ocular complication. These complications occurred more frequently among those with CD4 counts below 200 cells/μL. Of the participants with HIV-related ocular complications, 11 (23 %) had retinal microvasculopathy, 10 (21 %) showed allergic conjunctivitis, 7 (15 %) had HIV retinopathy and 7 (15 %) had conjunctival carcinoma. All the participants in the study were on first-line antiretroviral therapy; 68 % were females and 72 % were in the Stage 3 of the WHO Clinical Staging of HIV infection. The prevalence of ocular complications in HIV positive persons under treatment in Ghana is high. Lower CD4 + T cell counts coupled with age were predisposing factors to HIV-related ocular complications.

  16. Cultured corneal epithelia for ocular surface disease.

    PubMed Central

    Schwab, I R

    1999-01-01

    PURPOSE: To evaluate the potential efficacy for autologous and allogeneic expanded corneal epithelial cell transplants derived from harvested limbal corneal epithelial stem cells cultured in vitro for the management of ocular surface disease. METHODS: Human Subjects. Of the 19 human subjects included, 18 (20 procedures) underwent in vitro cultured corneal epithelial cell transplants using various carriers for the epithelial cells to determine the most efficacious approach. Sixteen patients (18 procedures on 17 eyes) received autologous transplants, and 2 patients (1 procedure each) received allogeneic sibling grafts. The presumed corneal epithelial stem cells from 1 patient did not grow in vitro. The carriers for the expanded corneal epithelial cells included corneal stroma, type 1 collagen (Vitrogen), soft contact lenses, collagen shields, and amniotic membrane for the autologous grafts and only amniotic membrane for the allogeneic sibling grafts. Histologic confirmation was reviewed on selected donor grafts. Amniotic membrane as carrier. Further studies were made to determine whether amniotic membrane might be the best carrier for the expanding corneal epithelial cells. Seventeen different combinations of tryspinization, sonication, scraping, and washing were studied to find the simplest, most effective method for removing the amniotic epithelium while still preserving the histologic appearance of the basement membrane of the amnion. Presumed corneal epithelial stem cells were harvested and expanded in vitro and applied to the amniotic membrane to create a composite graft. Thus, the composite graft consisted of the amniotic membrane from which the original epithelium had been removed without significant histologic damage to the basement membrane, and the expanded corneal epithelial stem cells, which had been applied to and had successfully adhered to the denuded amniotic membrane. Animal model. Twelve rabbits had the ocular surface of 1 eye damaged in a standard

  17. Weight loss and reduced body temperature determine humane endpoints in a mouse model of ocular herpesvirus infection.

    PubMed

    Hankenson, F Claire; Ruskoski, Nicholas; van Saun, Marjorie; Ying, Gui-Shuang; Oh, Jaewook; Fraser, Nigel W

    2013-01-01

    Herpes simplex virus (HSV) has been studied in well-established mouse models to generate latently infected animals for investigations into viral pathogenesis, latency mechanisms, and reactivation. Mice exhibit clinical signs of debilitating infection, during which time they may become severely ill before recovery or die spontaneously. Because the cohort of mice that does survive provides valuable data on latency, there is keen interest in developing methodologies for earlier detection and treatment of severe disease to ultimately increase survival rates. Here, BALB/c mice were inoculated ocularly with either a wildtype (LAT(+)) or mutant (LAT(-)) strain of HSV1. Mice were monitored daily through day 30 after infection; trigeminal ganglia were harvested at day 60 to assess viral DNA load. Cages were provided with nesting material, and fluid supplementation was administered to mice with body temperatures of 35 °C or lower, as measured by subcutaneous microchip thermometry. The results showed that infected mice with temperatures less than 34.5 °C did not recover to normothermia and were euthanized or spontaneously died, regardless of infective viral strain. By using a combination of criteria including body temperature (less than 34.5 °C) and weight loss (more than 0.05 g daily) for removal of animals from the study, approximately 98% of mice that died spontaneously could have been euthanized prior to death, without concern of potential recovery to the experimental endpoint (100% specificity). Frequent monitoring of alterations to general wellbeing, body temperature, and weight was crucial for establishing humane endpoints in this ocular HSV model.

  18. Cytotoxicity and genotoxicity of bacterial magnetosomes against human retinal pigment epithelium cells.

    PubMed

    Qi, Lei; Lv, Xiujuan; Zhang, Tongwei; Jia, Peina; Yan, Ruiying; Li, Shuli; Zou, Ruitao; Xue, Yuhua; Dai, Liming

    2016-06-01

    A variety of nanomaterials have been developed for ocular diseases. The ability of these nanomaterials to pass through the blood-ocular barrier and their biocompatibility are essential characteristics that must be considered. Bacterial magnetosomes (BMs) are a type of biogenic magnetic nanomaterials synthesized by magnetotactic bacteria. Due to their unique biomolecular membrane shell and narrow size distribution of approximately 30 nm, BMs can pass through the blood-brain barrier. The similarity of the blood-ocular barrier to the blood-brain barrier suggests that BMs have great potential as treatments for ocular diseases. In this work, BMs were isolated from magnetotactic bacteria and evaluated in various cytotoxicity and genotoxicity studies in human retinal pigment epithelium (ARPE-19) cells. The BMs entered ARPE-19 cells by endocytosis after a 6-h incubation and displayed much lower cytotoxicity than chemically synthesized magnetic nanoparticles (MNPs). MNPs exhibited significantly higher genotoxicity than BMs and promoted the expression of Bax (the programmed cell death acceleration protein) and the induction of greater cell necrosis. In BM-treated cells, apoptosis tended to be suppressed via increased expression of the Bcl-2 protein. In conclusion, BMs display excellent biocompatibility and potential for use in the treatment of ocular diseases.

  19. Cytotoxicity and genotoxicity of bacterial magnetosomes against human retinal pigment epithelium cells

    NASA Astrophysics Data System (ADS)

    Qi, Lei; Lv, Xiujuan; Zhang, Tongwei; Jia, Peina; Yan, Ruiying; Li, Shuli; Zou, Ruitao; Xue, Yuhua; Dai, Liming

    2016-06-01

    A variety of nanomaterials have been developed for ocular diseases. The ability of these nanomaterials to pass through the blood-ocular barrier and their biocompatibility are essential characteristics that must be considered. Bacterial magnetosomes (BMs) are a type of biogenic magnetic nanomaterials synthesized by magnetotactic bacteria. Due to their unique biomolecular membrane shell and narrow size distribution of approximately 30 nm, BMs can pass through the blood-brain barrier. The similarity of the blood-ocular barrier to the blood-brain barrier suggests that BMs have great potential as treatments for ocular diseases. In this work, BMs were isolated from magnetotactic bacteria and evaluated in various cytotoxicity and genotoxicity studies in human retinal pigment epithelium (ARPE-19) cells. The BMs entered ARPE-19 cells by endocytosis after a 6-h incubation and displayed much lower cytotoxicity than chemically synthesized magnetic nanoparticles (MNPs). MNPs exhibited significantly higher genotoxicity than BMs and promoted the expression of Bax (the programmed cell death acceleration protein) and the induction of greater cell necrosis. In BM-treated cells, apoptosis tended to be suppressed via increased expression of the Bcl-2 protein. In conclusion, BMs display excellent biocompatibility and potential for use in the treatment of ocular diseases.

  20. Cytotoxicity and genotoxicity of bacterial magnetosomes against human retinal pigment epithelium cells

    PubMed Central

    Qi, Lei; Lv, Xiujuan; Zhang, Tongwei; Jia, Peina; Yan, Ruiying; Li, Shuli; Zou, Ruitao; Xue, Yuhua; Dai, Liming

    2016-01-01

    A variety of nanomaterials have been developed for ocular diseases. The ability of these nanomaterials to pass through the blood-ocular barrier and their biocompatibility are essential characteristics that must be considered. Bacterial magnetosomes (BMs) are a type of biogenic magnetic nanomaterials synthesized by magnetotactic bacteria. Due to their unique biomolecular membrane shell and narrow size distribution of approximately 30 nm, BMs can pass through the blood-brain barrier. The similarity of the blood-ocular barrier to the blood-brain barrier suggests that BMs have great potential as treatments for ocular diseases. In this work, BMs were isolated from magnetotactic bacteria and evaluated in various cytotoxicity and genotoxicity studies in human retinal pigment epithelium (ARPE-19) cells. The BMs entered ARPE-19 cells by endocytosis after a 6-h incubation and displayed much lower cytotoxicity than chemically synthesized magnetic nanoparticles (MNPs). MNPs exhibited significantly higher genotoxicity than BMs and promoted the expression of Bax (the programmed cell death acceleration protein) and the induction of greater cell necrosis. In BM-treated cells, apoptosis tended to be suppressed via increased expression of the Bcl-2 protein. In conclusion, BMs display excellent biocompatibility and potential for use in the treatment of ocular diseases. PMID:27246808

  1. MRI in ocular drug delivery.

    PubMed

    Li, S Kevin; Lizak, Martin J; Jeong, Eun-Kee

    2008-11-01

    Conventional pharmacokinetic methods for studying ocular drug delivery are invasive and cannot be conveniently applied to humans. The advancement of MRI technology has provided new opportunities in ocular drug-delivery research. MRI provides a means to non-invasively and continuously monitor ocular drug-delivery systems with a contrast agent or compound labeled with a contrast agent. It is a useful technique in pharmacokinetic studies, evaluation of drug-delivery methods, and drug-delivery device testing. Although the current status of the technology presents some major challenges to pharmaceutical research using MRI, it has a lot of potential. In the past decade, MRI has been used to examine ocular drug delivery via the subconjunctival route, intravitreal injection, intrascleral injection to the suprachoroidal space, episcleral and intravitreal implants, periocular injections, and ocular iontophoresis. In this review, the advantages and limitations of MRI in the study of ocular drug delivery are discussed. Different MR contrast agents and MRI techniques for ocular drug-delivery research are compared. Ocular drug-delivery studies using MRI are reviewed.

  2. MRI in ocular drug delivery

    PubMed Central

    Li, S. Kevin; Lizak, Martin J.; Jeong, Eun-Kee

    2008-01-01

    Conventional pharmacokinetic methods for studying ocular drug delivery are invasive and cannot be conveniently applied to humans. The advancement of MRI technology has provided new opportunities in ocular drug-delivery research. MRI provides a means to non-invasively and continuously monitor ocular drug-delivery systems with a contrast agent or compound labeled with a contrast agent. It is a useful technique in pharmacokinetic studies, evaluation of drug-delivery methods, and drug-delivery device testing. Although the current status of the technology presents some major challenges to pharmaceutical research using MRI, it has a lot of potential. In the past decade, MRI has been used to examine ocular drug delivery via the subconjunctival route, intravitreal injection, intrascleral injection to the suprachoroidal space, episcleral and intravitreal implants, periocular injections, and ocular iontophoresis. In this review, the advantages and limitations of MRI in the study of ocular drug delivery are discussed. Different MR contrast agents and MRI techniques for ocular drug-delivery research are compared. Ocular drug-delivery studies using MRI are reviewed. PMID:18186077

  3. Herbal Extracts That Reduce Ocular Oxidative Stress May Enhance Attentive Performance in Humans.

    PubMed

    Cho, Hohyun; Kwon, Moonyoung; Jang, Hyojung; Lee, Jee-Bum; Yoon, Kyung Chul; Jun, Sung Chan

    2016-01-01

    We used herbal extracts in this study to investigate the effects of blue-light-induced oxidative stress on subjects' attentive performance, which is also associated with work performance. We employed an attention network test (ANT) to measure the subjects' work performance indirectly and used herbal extracts to reduce ocular oxidative stress. Thirty-two subjects participated in either an experimental group (wearing glasses containing herbal extracts) or a control group (wearing glasses without herbal extracts). During the ANT experiment, we collected electroencephalography (EEG) and electrooculography (EOG) data and measured button responses. In addition, electrocardiogram (ECG) data were collected before and after the experiments. The EOG results showed that the experimental group exhibited a reduced number of eye blinks per second during the experiment and faster button responses with a smaller variation than did the control group; this group also showed relatively more sustained tension in their ECG results. In the EEG analysis, the experimental group had significantly greater cognitive processing, with larger P300 and parietal 2-6 Hz activity, an orienting effect with neural processing of frontal area, high beta activity in the occipital area, and an alpha and beta recovery process after the button response. We concluded that reducing blue-light-induced oxidative stress with herbal extracts may be associated with reducing the number of eye blinks and enhancing attentive performance.

  4. EEG and ocular correlates of circadian melatonin phase and human performance decrements during sleep loss

    NASA Technical Reports Server (NTRS)

    Cajochen, C.; Khalsa, S. B.; Wyatt, J. K.; Czeisler, C. A.; Dijk, D. J.

    1999-01-01

    The aim of this study was to quantify the associations between slow eye movements (SEMs), eye blink rate, waking electroencephalogram (EEG) power density, neurobehavioral performance, and the circadian rhythm of plasma melatonin in a cohort of 10 healthy men during up to 32 h of sustained wakefulness. The time course of neurobehavioral performance was characterized by fairly stable levels throughout the first 16 h of wakefulness followed by deterioration during the phase of melatonin secretion. This deterioration was closely associated with an increase in SEMs. Frontal low-frequency EEG activity (1-7 Hz) exhibited a prominent increase with time awake and little circadian modulation. EEG alpha activity exhibited circadian modulation. The dynamics of SEMs and EEG activity were phase locked to changes in neurobehavioral performance and lagged the plasma melatonin rhythm. The data indicate that frontal areas of the brain are more susceptible to sleep loss than occipital areas. Frontal EEG activity and ocular parameters may be used to monitor and predict changes in neurobehavioral performance associated with sleep loss and circadian misalignment.

  5. Herbal Extracts That Reduce Ocular Oxidative Stress May Enhance Attentive Performance in Humans

    PubMed Central

    Cho, Hohyun; Kwon, Moonyoung; Jang, Hyojung; Lee, Jee-Bum; Yoon, Kyung Chul

    2016-01-01

    We used herbal extracts in this study to investigate the effects of blue-light-induced oxidative stress on subjects' attentive performance, which is also associated with work performance. We employed an attention network test (ANT) to measure the subjects' work performance indirectly and used herbal extracts to reduce ocular oxidative stress. Thirty-two subjects participated in either an experimental group (wearing glasses containing herbal extracts) or a control group (wearing glasses without herbal extracts). During the ANT experiment, we collected electroencephalography (EEG) and electrooculography (EOG) data and measured button responses. In addition, electrocardiogram (ECG) data were collected before and after the experiments. The EOG results showed that the experimental group exhibited a reduced number of eye blinks per second during the experiment and faster button responses with a smaller variation than did the control group; this group also showed relatively more sustained tension in their ECG results. In the EEG analysis, the experimental group had significantly greater cognitive processing, with larger P300 and parietal 2–6 Hz activity, an orienting effect with neural processing of frontal area, high beta activity in the occipital area, and an alpha and beta recovery process after the button response. We concluded that reducing blue-light-induced oxidative stress with herbal extracts may be associated with reducing the number of eye blinks and enhancing attentive performance. PMID:28090203

  6. EEG and ocular correlates of circadian melatonin phase and human performance decrements during sleep loss

    NASA Technical Reports Server (NTRS)

    Cajochen, C.; Khalsa, S. B.; Wyatt, J. K.; Czeisler, C. A.; Dijk, D. J.

    1999-01-01

    The aim of this study was to quantify the associations between slow eye movements (SEMs), eye blink rate, waking electroencephalogram (EEG) power density, neurobehavioral performance, and the circadian rhythm of plasma melatonin in a cohort of 10 healthy men during up to 32 h of sustained wakefulness. The time course of neurobehavioral performance was characterized by fairly stable levels throughout the first 16 h of wakefulness followed by deterioration during the phase of melatonin secretion. This deterioration was closely associated with an increase in SEMs. Frontal low-frequency EEG activity (1-7 Hz) exhibited a prominent increase with time awake and little circadian modulation. EEG alpha activity exhibited circadian modulation. The dynamics of SEMs and EEG activity were phase locked to changes in neurobehavioral performance and lagged the plasma melatonin rhythm. The data indicate that frontal areas of the brain are more susceptible to sleep loss than occipital areas. Frontal EEG activity and ocular parameters may be used to monitor and predict changes in neurobehavioral performance associated with sleep loss and circadian misalignment.

  7. Freezing human ES cells.

    PubMed

    Trish, Erin; Dimos, John; Eggan, Kevin

    2006-10-12

    Here we demonstrate how our lab freezes HuES human embryonic stem cell lines. A healthy, exponentially expanding culture is washed with PBS to remove residual media that could otherwise quench the Trypsin reaction. Warmed 0.05% Trypsin-EDTA is then added to cover the cells, and the plate allowed to incubate for up to 5 mins at room temperature. During this time cells can be observed rounding, and colonies lifting off the plate surface. Gentle repeated pipetting will remove cells and colonies from the plate surface. Trypsinized cells are placed in a standard conical tube containing pre-warmed hES cell media to quench remaining trypsin, and then spun. Cells are resuspended growth media at a concentration of approximately one million cells in one mL of media, a concentration such that one frozen aliquot is sufficient to resurrect a culture on a 10 cm plate. After cells are adequately resuspended, ice cold freezing media is added at equal volume. Cell suspensions are mixed thoroughly, aliquoted into freezing vials, and allowed to slowly freeze to -80 C over 24 hours. Frozen cells can then moved to the vapor phase of liquid nitrogen for long term storage, or remain at -80 for approximately six months.

  8. Ocular phototherapy.

    PubMed

    Singh, A D

    2013-02-01

    Phototherapy can be translated to mean 'light or radiant energy-induced treatment.' Lasers have become the exclusive source of light or radiant energy for all applications of phototherapy. Depending on the wavelength, intensity, and duration of exposure, tissues can either absorb the energy (photocoagulation, thermotherapy, and photodynamic therapy (PDT)) or undergo ionization (photodisruption). For phototherapy to be effective, the energy has to be absorbed by tissues or more specifically by naturally occurring pigment (xanthophyll, haemoglobin, and melanin) within them. In tissues or tumours that lack natural pigment, dyes (verteporphin, Visudyne) with narrow absorption spectrum can be injected intravenously that act as focal absorbent of laser energy after they have preferentially localized within the tumour. Ocular phototherapy has broad applications in treatment of ocular tumours. Laser photocoagulation, thermotherapy, and PDT can be delivered with low rates of complications and with ease in the outpatient setting. Review of the current literature suggests excellent results when these treatments are applied for benign tumours, particularly for vascular tumours such as circumscribed choroidal haemangioma. For primary malignant tumours, such as choroidal melanoma, thermotherapy, and PDT do not offer local tumour control rates that are equivalent or higher than those achieved with plaque or proton radiation therapy. However, for secondary malignant tumours (choroidal metastases), thermotherapy and PDT can be applied as a palliative treatment. Greater experience is necessary to fully comprehend risks, comparative benefits, and complication of ocular phototherapy of ocular tumours.

  9. Ocular tropism of respiratory viruses.

    PubMed

    Belser, Jessica A; Rota, Paul A; Tumpey, Terrence M

    2013-03-01

    Respiratory viruses (including adenovirus, influenza virus, respiratory syncytial virus, coronavirus, and rhinovirus) cause a broad spectrum of disease in humans, ranging from mild influenza-like symptoms to acute respiratory failure. While species D adenoviruses and subtype H7 influenza viruses are known to possess an ocular tropism, documented human ocular disease has been reported following infection with all principal respiratory viruses. In this review, we describe the anatomical proximity and cellular receptor distribution between ocular and respiratory tissues. All major respiratory viruses and their association with human ocular disease are discussed. Research utilizing in vitro and in vivo models to study the ability of respiratory viruses to use the eye as a portal of entry as well as a primary site of virus replication is highlighted. Identification of shared receptor-binding preferences, host responses, and laboratory modeling protocols among these viruses provides a needed bridge between clinical and laboratory studies of virus tropism.

  10. Ocular Tropism of Respiratory Viruses

    PubMed Central

    Rota, Paul A.; Tumpey, Terrence M.

    2013-01-01

    SUMMARY Respiratory viruses (including adenovirus, influenza virus, respiratory syncytial virus, coronavirus, and rhinovirus) cause a broad spectrum of disease in humans, ranging from mild influenza-like symptoms to acute respiratory failure. While species D adenoviruses and subtype H7 influenza viruses are known to possess an ocular tropism, documented human ocular disease has been reported following infection with all principal respiratory viruses. In this review, we describe the anatomical proximity and cellular receptor distribution between ocular and respiratory tissues. All major respiratory viruses and their association with human ocular disease are discussed. Research utilizing in vitro and in vivo models to study the ability of respiratory viruses to use the eye as a portal of entry as well as a primary site of virus replication is highlighted. Identification of shared receptor-binding preferences, host responses, and laboratory modeling protocols among these viruses provides a needed bridge between clinical and laboratory studies of virus tropism. PMID:23471620

  11. Characterizing motility dynamics in human RPE cells

    NASA Astrophysics Data System (ADS)

    Liu, Zhuolin; Kurokawa, Kazuhiro; Zhang, Furu; Miller, Donald T.

    2017-02-01

    Retinal pigment epithelium (RPE) cells are vital to health of the outer retina, however, are often compromised in ageing and ocular diseases that lead to blindness. Early manifestation of RPE disruption occurs at the cellular level, but while in vivo biomarkers at this scale hold considerable promise, RPE cells have proven extremely challenging to image in the living human eye. Recently we addressed this problem by using organelle motility as a novel contrast agent to enhance the RPE cell in conjunction with 3D resolution of adaptive optics-optical coherence tomography (AO-OCT) to section the RPE layer. In this study, we expand on the central novelty of our method - organelle motility - by characterizing the dynamics of the motility in individual RPE cells, important because of its direct link to RPE physiology. To do this, AO-OCT videos of the same retinal patch were acquired at approximately 1 min intervals or less, time stamped, and registered in 3D with sub-cellular accuracy. Motility was quantified by an exponential decay time constant, the time for motility to decorrelate the speckle field across an RPE cell. In two normal subjects, we found the decay time constant to be just 3 seconds, thus indicating rapid motility in normal RPE cells.

  12. The ocular albinism type 1 protein, an intracellular G protein-coupled receptor, regulates melanosome transport in pigment cells.

    PubMed

    Palmisano, Ilaria; Bagnato, Paola; Palmigiano, Angela; Innamorati, Giulio; Rotondo, Giuseppe; Altimare, Domenico; Venturi, Consuelo; Sviderskaya, Elena V; Piccirillo, Rosanna; Coppola, Massimiliano; Marigo, Valeria; Incerti, Barbara; Ballabio, Andrea; Surace, Enrico M; Tacchetti, Carlo; Bennett, Dorothy C; Schiaffino, Maria Vittoria

    2008-11-15

    The protein product of the ocular albinism type 1 gene, named OA1, is a pigment cell-specific G protein-coupled receptor exclusively localized to intracellular organelles, namely lysosomes and melanosomes. Loss of OA1 function leads to the formation of macromelanosomes, suggesting that this receptor is implicated in organelle biogenesis, however the mechanism involved in the pathogenesis of the disease remains obscure. We report here the identification of an unexpected abnormality in melanosome distribution both in retinal pigment epithelium (RPE) and skin melanocytes of Oa1-knock-out (KO) mice, consisting in a displacement of the organelles from the central cytoplasm towards the cell periphery. Despite their depletion from the microtubule (MT)-enriched perinuclear region, Oa1-KO melanosomes were able to aggregate at the centrosome upon disruption of the actin cytoskeleton or expression of a dominant-negative construct of myosin Va. Consistently, quantification of organelle transport in living cells revealed that Oa1-KO melanosomes displayed a severe reduction in MT-based motility; however, this defect was rescued to normal following inhibition of actin-dependent capture at the cell periphery. Together, these data point to a defective regulation of organelle transport in the absence of OA1 and imply that the cytoskeleton might represent a downstream effector of this receptor. Furthermore, our results enlighten a novel function for OA1 in pigment cells and suggest that ocular albinism type 1 might result from a different pathogenetic mechanism than previously thought, based on an organelle-autonomous signalling pathway implicated in the regulation of both membrane traffic and transport.

  13. The chick eye in vision research: An excellent model for the study of ocular disease.

    PubMed

    Wisely, C Ellis; Sayed, Javed A; Tamez, Heather; Zelinka, Chris; Abdel-Rahman, Mohamed H; Fischer, Andy J; Cebulla, Colleen M

    2017-06-28

    The domestic chicken, Gallus gallus, serves as an excellent model for the study of a wide range of ocular diseases and conditions. The purpose of this manuscript is to outline some anatomic, physiologic, and genetic features of this organism as a robust animal model for vision research, particularly for modeling human retinal disease. Advantages include a sequenced genome, a large eye, relative ease of handling and maintenance, and ready availability. Relevant similarities and differences to humans are highlighted for ocular structures as well as for general physiologic processes. Current research applications for various ocular diseases and conditions, including ocular imaging with spectral domain optical coherence tomography, are discussed. Several genetic and non-genetic ocular disease models are outlined, including for pathologic myopia, keratoconus, glaucoma, retinal detachment, retinal degeneration, ocular albinism, and ocular tumors. Finally, the use of stem cell technology to study the repair of damaged tissues in the chick eye is discussed. Overall, the chick model provides opportunities for high-throughput translational studies to more effectively prevent or treat blinding ocular diseases. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Activation of cytokines and NF-kappa B in corneal epithelial cells infected by respiratory syncytial virus: potential relevance in ocular inflammation and respiratory infection

    PubMed Central

    Bitko, Vira; Garmon, Nicolle E; Cao, Tin; Estrada, Benjamin; Oakes, John E; Lausch, Robert N; Barik, Sailen

    2004-01-01

    Background Respiratory syncytial virus (RSV) is a major cause of lower respiratory tract infection, claiming millions of lives annually. The virus infects various cells of the respiratory tract as well as resident inflammatory cells such as macrophages. Infection activates a variety of cellular factors such as cytokines and the pro-inflammatory transcription factor, NF-kappa B, all of which are important players in the respiratory disease. However, the exact natural route of RSV infection and its etiology remain relatively unknown. In this paper, we test the hypothesis that human corneal epithelial cells, which constitute the outermost layer of the cornea, can be infected with RSV, and that the infection leads to the activation of proinflammatory macromolecules. Results Corneal swabs obtained from pediatric patients with acute respiratory disease were found to contain RSV at a high frequency (43 positive out of 72 samples, i.e., 60%). Primary corneal epithelial cells in tissue culture supported robust infection and productive growth of RSV. Infection resulted in the activation of TNF-α, IL-6 and sixteen chemokines as well as NF-κB. Three proinflammatory CXC chemokines (MIG, I-TAC, IP-10) underwent the greatest activation. Conclusions The ocular epithelium is readily infected by RSV. The pro-inflammatory cytokines are likely to play critical roles in the etiology of inflammation and conjunctivitis commonly seen in pediatric patients with respiratory infections. RSV-eye interactions have important implications in RSV transmission, immunopathology of RSV disease, and in the management of conjunctivitis. PMID:15256003

  15. Treatment of Acute Ocular Chemical Burns.

    PubMed

    Sharma, Namrata; Kaur, Manpreet; Agarwal, Tushar; Sangwan, Virender S; Vajpayee, Rasik B

    2017-09-18

    Ocular chemical burns are an ophthalmic emergency and are responsible for 11.5% to 22.1% of ocular injuries. Immediate copious irrigation is universally recommended in acute ocular burns to remove the offending agent and minimize damage. Conventional medical therapy consists of the use of agents that promote epithelialization, minimize inflammation, and prevent cicatricial complications. Biological fluids such as autologous serum, umbilical cord blood serum, platelet-rich plasma, and amniotic membrane suspension are a rich source of growth factors and promote healing when used as adjuncts to conventional therapy. Surgical treatment of acute ocular burns includes the debridement of the necrotic tissue, application of tissue adhesives, tenoplasty, and tectonic keratoplasty. Amniotic membrane transplantation is a novel surgical treatment that is increasingly being used as an adjunct to conventional treatment to promote epithelial healing, minimize pain, and restore visual acuity. Various experimental treatments that aim to promote wound healing and minimize inflammation are being evaluated such as human mesenchymal and adipose stem cells, beta-1,3 glucan, angiotensin-converting enzyme inhibitors, cultivated fibroblasts, zinc desferrioxamine, anti-fibrinolytic agents, antioxidants, collagen cross-linking, and inhibitors of corneal neovascularization. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Ocular Toxicity Testing of Lunar Dust

    NASA Technical Reports Server (NTRS)

    Meyers, Valerie E.

    2010-01-01

    This slide presentation reviews the use of ocular testing to determine the toxicity of lunar dust. The OECD recommendations are reviewed. With these recommendations in mind the test methodology was to use EpiOcular, tissues derived from normal human epidermal keratinocytes, the cells of which have been differentiated on cell culture inserts to form a multi-layered structure, which closely parallels the corneal epithelium and to dose the tissue with 100 mg dust from various sources. The in-vitro study provides evidence that lunar dust is not severely corrosive or irritating, however, in vitro tests have limitations, and in vivo tests provides a more complete scenario, and information, it is recommended that in vivo tests be performed.

  17. Human innate lymphoid cells.

    PubMed

    Mjösberg, Jenny; Spits, Hergen

    2016-11-01

    Innate lymphoid cells (ILCs) are increasingly acknowledged as important mediators of immune homeostasis and pathology. ILCs act as early orchestrators of immunity, responding to epithelium-derived signals by expressing an array of cytokines and cell-surface receptors, which shape subsequent immune responses. As such, ILCs make up interesting therapeutic targets for several diseases. In patients with allergy and asthma, group 2 innate lymphoid cells produce high amounts of IL-5 and IL-13, thereby contributing to type 2-mediated inflammation. Group 3 innate lymphoid cells are implicated in intestinal homeostasis and psoriasis pathology through abundant IL-22 production, whereas group 1 innate lymphoid cells are accumulated in chronic inflammation of the gut (inflammatory bowel disease) and lung (chronic obstructive pulmonary disease), where they contribute to IFN-γ-mediated inflammation. Although the ontogeny of mouse ILCs is slowly unraveling, the development of human ILCs is far from understood. In addition, the growing complexity of the human ILC family in terms of previously unrecognized functional heterogeneity and plasticity has generated confusion within the field. Here we provide an updated view on the function and plasticity of human ILCs in tissue homeostasis and disease. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  18. Clusterin Seals the Ocular Surface Barrier in Mouse Dry Eye.

    PubMed

    Bauskar, Aditi; Mack, Wendy J; Mauris, Jerome; Argüeso, Pablo; Heur, Martin; Nagel, Barbara A; Kolar, Grant R; Gleave, Martin E; Nakamura, Takahiro; Kinoshita, Shigeru; Moradian-Oldak, Janet; Panjwani, Noorjahan; Pflugfelder, Stephen C; Wilson, Mark R; Fini, M Elizabeth; Jeong, Shinwu

    2015-01-01

    Dry eye is a common disorder caused by inadequate hydration of the ocular surface that results in disruption of barrier function. The homeostatic protein clusterin (CLU) is prominent at fluid-tissue interfaces throughout the body. CLU levels are reduced at the ocular surface in human inflammatory disorders that manifest as severe dry eye, as well as in a preclinical mouse model for desiccating stress that mimics dry eye. Using this mouse model, we show here that CLU prevents and ameliorates ocular surface barrier disruption by a remarkable sealing mechanism dependent on attainment of a critical all-or-none concentration. When the CLU level drops below the critical all-or-none threshold, the barrier becomes vulnerable to desiccating stress. CLU binds selectively to the ocular surface subjected to desiccating stress in vivo, and in vitro to the galectin LGALS3, a key barrier component. Positioned in this way, CLU not only physically seals the ocular surface barrier, but it also protects the barrier cells and prevents further damage to barrier structure. These findings define a fundamentally new mechanism for ocular surface protection and suggest CLU as a biotherapeutic for dry eye.

  19. Clusterin Seals the Ocular Surface Barrier in Mouse Dry Eye

    PubMed Central

    Bauskar, Aditi; Mack, Wendy J.; Mauris, Jerome; Argüeso, Pablo; Heur, Martin; Nagel, Barbara A.; Kolar, Grant R.; Gleave, Martin E.; Nakamura, Takahiro; Kinoshita, Shigeru; Moradian-Oldak, Janet; Panjwani, Noorjahan; Pflugfelder, Stephen C.; Wilson, Mark R.; Fini, M. Elizabeth; Jeong, Shinwu

    2015-01-01

    Dry eye is a common disorder caused by inadequate hydration of the ocular surface that results in disruption of barrier function. The homeostatic protein clusterin (CLU) is prominent at fluid-tissue interfaces throughout the body. CLU levels are reduced at the ocular surface in human inflammatory disorders that manifest as severe dry eye, as well as in a preclinical mouse model for desiccating stress that mimics dry eye. Using this mouse model, we show here that CLU prevents and ameliorates ocular surface barrier disruption by a remarkable sealing mechanism dependent on attainment of a critical all-or-none concentration. When the CLU level drops below the critical all-or-none threshold, the barrier becomes vulnerable to desiccating stress. CLU binds selectively to the ocular surface subjected to desiccating stress in vivo, and in vitro to the galectin LGALS3, a key barrier component. Positioned in this way, CLU not only physically seals the ocular surface barrier, but it also protects the barrier cells and prevents further damage to barrier structure. These findings define a fundamentally new mechanism for ocular surface protection and suggest CLU as a biotherapeutic for dry eye. PMID:26402857

  20. Culture, Immortalization, and Characterization of Human Meibomian Gland Epithelial Cells

    PubMed Central

    Liu, Shaohui; Hatton, Mark P.; Khandelwal, Payal

    2010-01-01

    Purpose. Meibomian gland epithelial cells are essential in maintaining the health and integrity of the ocular surface. However, very little is known about their physiological regulation. In this study, the cellular control mechanisms were explored, first to establish a defined culture system for the maintenance of primary epithelial cells from human meibomian glands and, second, to immortalize these cells, thereby developing a preclinical model that could be used to identify factors that regulate cell activity. Methods. Human meibomian glands were removed from lid segments after surgery, enzymatically digested, and dissociated. Isolated epithelial cells were cultured in media with or without serum and/or 3T3 feeder layers. To attempt immortalization, the cells were exposed to retroviral human telomerase reverse transcriptase (hTERT) and/or SV40 large T antigen cDNA vectors, and antibiotic-resistant cells were selected, expanded, and subcultured. Analyses for possible biomarkers, cell proliferation and differentiation, lipid-related enzyme gene expression, and the cellular response to androgen were performed with biochemical, histologic, and molecular biological techniques. Results. It was possible to isolate viable human meibomian gland epithelial cells and to culture them in serum-free medium. These cells proliferated, survived through at least the fifth passage, and contained neutral lipids. Infection with hTERT immortalized these cells, which accumulated neutral lipids during differentiation, expressed multiple genes for lipogenic enzymes, responded to androgen, and continued to proliferate. Conclusions. The results show that human meibomian gland epithelial cells may be isolated, cultured, and immortalized. PMID:20335607

  1. Short-term adaptive changes in the human vestibulo-ocular reflex arc.

    PubMed

    Gonshor, A; Jones, G M

    1976-04-01

    1. Two sets of experiments have examined the vestibulo-ocular response (VOR) to repeated sinusoidal rotation (A) in the dark and (B) after attempting visual tracking of a mirror-reversed image of the visual surround.2. In both A and B a horizontal sinusoidal rotational stimulus of 1/6 Hz and 60 degrees /sec angular velocity amplitude was employed, specifically chosen to lie within the presumed range of natural stimulation of the semicircular canals.3. In A each of seven subjects underwent ten 2-min runs of the standard stimulus in the dark on each of three consecutive days, with 3-min rest periods between runs. Using d.c. electro-oculography (EOG) the VOR gain was measured throughout as eye velocity/head velocity. Mental arousal was maintained by competitive mental arithmetic. Constancy of EOG gain was assured by 50 min dark adaptation before experimentation.4. The results of A showed no consistent change of VOR gain over the three times scales of a run, a day and the 3-day experiment.5. In B the same subjects underwent a similar pattern of vestibular stimulation, but during eight of the 2-min daily runs they attempted the reversed visual tracking task. VOR gain was measured during the 1st, 6th and last runs which were conducted in the dark for this purpose. Constancy of EOG gain was maintained by using red light throughout.6. The results of B showed a substantial (approx. 25%) and highly significant (P < 0.001) reduction of VOR gain attributable solely to the 16 min of reversed visual tracking attempted during the 50 min daily experiment. In addition the pre-test control gain was lower on day 3 than on day 1 (approx. 10% attenuation, P < 0.01) indicating a small cumulative effect from beginning to end of the 3-day experiment.7. It is concluded (A) that the repeated vestibular stimulus did not itself cause significant attenuation of VOR gain, but (B) that superposition of a reversed visual tracking task did induce retained VOR attenuation which was solely due to

  2. Ocular metastases

    PubMed Central

    Cohen, V M L

    2013-01-01

    The eye is a rare site for disseminated malignancy because of the absence of a lymphatic system. Metastases to the ocular structures occur by haematogenous spread and therefore the parts of the eye with the best vascular supply are most likely to be affected. Many patients with Stage 4 carcinomatosis (distal metastatic spread) already have a history of a previous primary cancer. However, this is not always the case for lung cancer as this can metastasise early to the uveal tract and therefore the ophthalmologist may be the first to discover the presence of terminal metastatic disease. Broadly speaking, treatment options are focused on improving the patients' quality of life if visual acuity is threatened. Long-term side effects of treatment need to be considered as systemic cancer treatments and therefore patient life expectancy is improving. In this manuscript, presented at the Cambridge symposium 2012, the diagnosis and challenges involved in the management of ocular metastases are presented. PMID:23222564

  3. Ocular onchocerciasis

    PubMed Central

    Thylefors, B.

    1978-01-01

    Well over 20 million people in the world are infected with Onchocerca volvulus and it is probable that 200 000-500 000 people are blind as a result of this infection, which is the most important cause of blindness in certain areas of Africa and Latin America. Treatment of the disease is difficult and often produces serious adverse reactions in the patient. Combined use of diethylcarbamazine citrate and suramin is still the most suitable form of treatment. Screening for the early detection of cases at high risk of ocular manifestations must be organized, and their treatment undertaken, if blindness is to be avoided. Prevention of ocular onchocerciasis is feasible, using vector control methods to reduce transmission, but the procedures are costly and may have to be maintained for many years. Research is needed to improve treatment and to find a chemoprophylactic agent or a preventive vaccine. PMID:307448

  4. Robotic ocular surgery.

    PubMed

    Tsirbas, A; Mango, C; Dutson, E

    2007-01-01

    Bimanual, three-dimensional robotic surgery has proved valuable for a variety of surgical procedures. To examine the use of a commercially available surgical robot for ocular microsurgery. Using a da Vinci surgical robot, ocular microsurgery was performed with repair of a corneal laceration in a porcine model. The experiments were performed on harvested porcine eyes placed in an anatomical position using a foam head on a standard operating room table. A video scope and two, 360 degrees -rotating, 8-mm, wrested-end effector instruments were placed over the eye with three robotic arms. The surgeon performed the actual procedures while positioned at a robotic system console that was located across the operating room suite. Each surgeon placed three 10-0 sutures, and this was documented with still and video photography. Ocular microsurgery was successfully performed using the da Vinci surgical robot. The robotic system provided excellent visualisation, as well as controlled and delicate placement of the sutures at the corneal level. Robotic ocular microsurgery is technically feasible in the porcine model and warrants consideration for evaluation in controlled human trials to deploy functioning remote surgical centres in areas without access to state-of-the-art surgical skill and technology.

  5. Robotic ocular surgery

    PubMed Central

    Tsirbas, A; Mango, C; Dutson, E

    2007-01-01

    Background Bimanual, three‐dimensional robotic surgery has proved valuable for a variety of surgical procedures. Aims To examine the use of a commercially available surgical robot for ocular microsurgery. Methods Using a da Vinci surgical robot, ocular microsurgery was performed with repair of a corneal laceration in a porcine model. The experiments were performed on harvested porcine eyes placed in an anatomical position using a foam head on a standard operating room table. A video scope and two, 360°‐rotating, 8‐mm, wrested‐end effector instruments were placed over the eye with three robotic arms. The surgeon performed the actual procedures while positioned at a robotic system console that was located across the operating room suite. Each surgeon placed three 10‐0 sutures, and this was documented with still and video photography. Results Ocular microsurgery was successfully performed using the da Vinci surgical robot. The robotic system provided excellent visualisation, as well as controlled and delicate placement of the sutures at the corneal level. Conclusions Robotic ocular microsurgery is technically feasible in the porcine model and warrants consideration for evaluation in controlled human trials to deploy functioning remote surgical centres in areas without access to state‐of‐the‐art surgical skill and technology. PMID:17020903

  6. Human dendritic cell subsets

    PubMed Central

    Collin, Matthew; McGovern, Naomi; Haniffa, Muzlifah

    2013-01-01

    Summary Dendritic cells are highly adapted to their role of presenting antigen and directing immune responses. Developmental studies indicate that DCs originate independently from monocytes and tissue macrophages. Emerging evidence also suggests that distinct subsets of DCs have intrinsic differences that lead to functional specialisation in the generation of immunity. Comparative studies are now allowing many of these properties to be more fully understood in the context of human immunology. PMID:23621371

  7. Ganglioside Profiling of the Human Retina: Comparison with Other Ocular Structures, Brain and Plasma Reveals Tissue Specificities

    PubMed Central

    Sibille, Estelle; Berdeaux, Olivier; Martine, Lucy; Bron, Alain M.; Creuzot-Garcher, Catherine P.; He, Zhiguo; Thuret, Gilles; Bretillon, Lionel; Masson, Elodie A. Y.

    2016-01-01

    Gangliosides make a wide family of glycosphingolipids, highly heterogeneous in both the ceramide moiety and the oligosaccharide chain. While ubiquitously expressed in mammalian tissues, they are particularly abundant in the brain and the peripheral nervous system. Gangliosides are known to play a crucial role in the development, maintenance and functional integrity of the nervous system. However, the expression and roles of gangliosides in the retina, although often considered as a window on the brain, has been far less studied. We performed an in-depth analysis of gangliosides of the human retina, especially using powerful LC/MS methods. We compared the pattern of ganglioside classes and ceramide molecular species of this tissue with other ocular structures and with brain and plasma in elderly human individuals. About a hundred of ganglioside molecular species among 15 distinct classes were detected illustrating the huge structural diversity of these compounds. The retina exhibited a very diverse ganglioside profile and shared several common features with the brain (prominence of tetraosylgangliosides, abundance of d20:1 long chain base and 18:0 fatty acid…). However, the retina stood out with the specific expression of GD3, GT3 and AcGT3, which further presented a peculiar molecular species distribution. The unique ganglioside pattern we observed in the human retina suggests that these ganglioside species play a specific role in the structure and function of this tissue. This lipidomic study, by highlighting retina specific ganglioside species, opens up novel research directions for a better understanding of the biological role of gangliosides in the retina. PMID:27997589

  8. Ganglioside Profiling of the Human Retina: Comparison with Other Ocular Structures, Brain and Plasma Reveals Tissue Specificities.

    PubMed

    Sibille, Estelle; Berdeaux, Olivier; Martine, Lucy; Bron, Alain M; Creuzot-Garcher, Catherine P; He, Zhiguo; Thuret, Gilles; Bretillon, Lionel; Masson, Elodie A Y

    2016-01-01

    Gangliosides make a wide family of glycosphingolipids, highly heterogeneous in both the ceramide moiety and the oligosaccharide chain. While ubiquitously expressed in mammalian tissues, they are particularly abundant in the brain and the peripheral nervous system. Gangliosides are known to play a crucial role in the development, maintenance and functional integrity of the nervous system. However, the expression and roles of gangliosides in the retina, although often considered as a window on the brain, has been far less studied. We performed an in-depth analysis of gangliosides of the human retina, especially using powerful LC/MS methods. We compared the pattern of ganglioside classes and ceramide molecular species of this tissue with other ocular structures and with brain and plasma in elderly human individuals. About a hundred of ganglioside molecular species among 15 distinct classes were detected illustrating the huge structural diversity of these compounds. The retina exhibited a very diverse ganglioside profile and shared several common features with the brain (prominence of tetraosylgangliosides, abundance of d20:1 long chain base and 18:0 fatty acid…). However, the retina stood out with the specific expression of GD3, GT3 and AcGT3, which further presented a peculiar molecular species distribution. The unique ganglioside pattern we observed in the human retina suggests that these ganglioside species play a specific role in the structure and function of this tissue. This lipidomic study, by highlighting retina specific ganglioside species, opens up novel research directions for a better understanding of the biological role of gangliosides in the retina.

  9. Ocular-following responses to white noise stimuli in humans reveal a novel nonlinearity that results from temporal sampling

    PubMed Central

    Sheliga, Boris M.; Quaia, Christian; FitzGibbon, Edmond J.; Cumming, Bruce G.

    2016-01-01

    White noise stimuli are frequently used to study the visual processing of broadband images in the laboratory. A common goal is to describe how responses are derived from Fourier components in the image. We investigated this issue by recording the ocular-following responses (OFRs) to white noise stimuli in human subjects. For a given speed we compared OFRs to unfiltered white noise with those to noise filtered with band-pass filters and notch filters. Removing components with low spatial frequency (SF) reduced OFR magnitudes, and the SF associated with the greatest reduction matched the SF that produced the maximal response when presented alone. This reduction declined rapidly with SF, compatible with a winner-take-all operation. Removing higher SF components increased OFR magnitudes. For higher speeds this effect became larger and propagated toward lower SFs. All of these effects were quantitatively well described by a model that combined two factors: (a) an excitatory drive that reflected the OFRs to individual Fourier components and (b) a suppression by higher SF channels where the temporal sampling of the display led to flicker. This nonlinear interaction has an important practical implication: Even with high refresh rates (150 Hz), the temporal sampling introduced by visual displays has a significant impact on visual processing. For instance, we show that this distorts speed tuning curves, shifting the peak to lower speeds. Careful attention to spectral content, in the light of this nonlinearity, is necessary to minimize the resulting artifact when using white noise patterns undergoing apparent motion. PMID:26762277

  10. Ocular-following responses to white noise stimuli in humans reveal a novel nonlinearity that results from temporal sampling.

    PubMed

    Sheliga, Boris M; Quaia, Christian; FitzGibbon, Edmond J; Cumming, Bruce G

    2016-01-01

    White noise stimuli are frequently used to study the visual processing of broadband images in the laboratory. A common goal is to describe how responses are derived from Fourier components in the image. We investigated this issue by recording the ocular-following responses (OFRs) to white noise stimuli in human subjects. For a given speed we compared OFRs to unfiltered white noise with those to noise filtered with band-pass filters and notch filters. Removing components with low spatial frequency (SF) reduced OFR magnitudes, and the SF associated with the greatest reduction matched the SF that produced the maximal response when presented alone. This reduction declined rapidly with SF, compatible with a winner-take-all operation. Removing higher SF components increased OFR magnitudes. For higher speeds this effect became larger and propagated toward lower SFs. All of these effects were quantitatively well described by a model that combined two factors: (a) an excitatory drive that reflected the OFRs to individual Fourier components and (b) a suppression by higher SF channels where the temporal sampling of the display led to flicker. This nonlinear interaction has an important practical implication: Even with high refresh rates (150 Hz), the temporal sampling introduced by visual displays has a significant impact on visual processing. For instance, we show that this distorts speed tuning curves, shifting the peak to lower speeds. Careful attention to spectral content, in the light of this nonlinearity, is necessary to minimize the resulting artifact when using white noise patterns undergoing apparent motion.

  11. Bilateral recurrent ocular surface squamous cell cancer associated with epidermodysplasia verruciformis

    PubMed Central

    Arora, Tarun; Sharma, Sourabh; Sharma, Namrata; Titiyal, Jeewan S

    2015-01-01

    A 17-year-old boy, presented with a 2-year history of bilateral, recurrent ocular surface mass. Dermatological evaluation revealed the presence of multiple hypopigmented macules over his body. Skin biopsy showed features typical of epidermodysplasia verruciformis. Topical mitomycin C (0.02%) was administered in both eyes for 6 weeks (three 1-week cycles over 6 weeks). While the mass in the left eye regressed, the mass in the right eye was excised under guidance of intraoperative frozen section. Triple-freeze thaw cryotherapy of the surrounding conjunctiva along with placement of amniotic membrane graft was performed. Postoperative mitomycin C (0.02%) was administered for another 6 weeks (three 1-week cycles over 6 weeks) in both eyes. At 4 years of follow-up, no recurrence has been noted. PMID:25636630

  12. Bilateral recurrent ocular surface squamous cell cancer associated with epidermodysplasia verruciformis.

    PubMed

    Arora, Tarun; Sharma, Sourabh; Sharma, Namrata; Titiyal, Jeewan S

    2015-01-30

    A 17-year-old boy, presented with a 2-year history of bilateral, recurrent ocular surface mass. Dermatological evaluation revealed the presence of multiple hypopigmented macules over his body. Skin biopsy showed features typical of epidermodysplasia verruciformis. Topical mitomycin C (0.02%) was administered in both eyes for 6 weeks (three 1-week cycles over 6 weeks). While the mass in the left eye regressed, the mass in the right eye was excised under guidance of intraoperative frozen section. Triple-freeze thaw cryotherapy of the surrounding conjunctiva along with placement of amniotic membrane graft was performed. Postoperative mitomycin C (0.02%) was administered for another 6 weeks (three 1-week cycles over 6 weeks) in both eyes. At 4 years of follow-up, no recurrence has been noted.

  13. Correlation of corneal thickness, endothelial cell density and anterior chamber depth with ocular surface temperature in normal subjects.

    PubMed

    Pattmöller, Johanna; Wang, Jiong; Zemova, Elena; Seitz, Berthold; Eppig, Timo; Langenbucher, Achim; Szentmáry, Nóra

    2015-09-01

    To analyze corneal surface temperature profile in a young and healthy study population and to determine the impact of corneal thickness (CT), anterior chamber depth (ACD), and endothelial cell density (ECD) on surface temperature. In this prospective, single-center study 61 healthy right eyes of 61 subjects without tear film pathologies (mean age 24.9 ± 6.7 years) were recruited. Ocular surface temperature (OST) was measured with the Ocular Surface Thermographer TG-1000. From Pentacam HR CT and ACD, and from specular microscopy ECD and central corneal thickness (CCT) were acquired. From the raw measurement data (OST, CT and ACD) we extracted a) local OST the corneal center and 3mm away from the center at the 3, 6, and 9 o'clock positions, and b) Zernike parameters Z1, Z2 and Z3 to evaluate the general temperature profile within a 6mm circular area around the center. Overall, there was no correlation between OST and CT, ACD or ECD. Local OST did not correlate with CT at any measurement position. On average local OST was highest at measurement positions where CT was lowest, but without reaching statistical significance. Baseline OST was highest at thin corneal regions and temperature decay over time was smallest in those regions. Z1, Z2 and Z3 correlated well with CT. In healthy subjects corneal thickness, endothelial cell density and anterior chamber depth have no effect on corneal surface temperature. The general temperature profile seems to be influenced by the corneal thickness profile effecting a higher temperature and lower decay at thinner corneal regions. Copyright © 2014. Published by Elsevier GmbH.

  14. Human mast cell transcriptome project.

    PubMed

    Saito, H; Nakajima, T; Matsumoto, K

    2001-05-01

    After draft reading of the human genome sequence, systemic analysis of the transcriptome (the whole transcripts present in a cell) is progressing especially in commonly available cell types. Until recently, human mast cells were not commonly available. We have succeeded to generate a substantial number of human mast cells from umbilical cord blood and from adult peripheral blood progenitors. Then, we have examined messenger RNA selectively transcribed in these mast cells using high-density oligonucleotide probe arrays. Many unexpected but important transcripts were selectively expressed in human mast cells. We discuss the results obtained from transcriptome screening by introducing our data regarding mast-cell-specific genes.

  15. An Evaluation of Automotive Interior Packages Based on Human Ocular and Joint Motor Properties

    NASA Astrophysics Data System (ADS)

    Tanaka, Yoshiyuki; Rakumatsu, Takeshi; Horiue, Masayoshi; Miyazaki, Tooru; Nishikawa, Kazuo; Nouzawa, Takahide; Tsuji, Toshio

    This paper proposes a new evaluation method of an automotive interior package based on human oculomotor and joint-motor properties. Assuming the long-term driving situation in the express high way, the three evaluation indices were designed on i) the ratio of head motion at gazing the driving items; ii) the load torque for maintaining the standard driving posture; and iii) the human force manipulability at the end-point of human extremities. Experiments were carried out for two different interior packages with four subjects who have the special knowledge on the automobile development. Evaluation results demonstrate that the proposed method can quantitatively analyze the driving interior in good agreement with the generally accepted subjective opinion in the automobile industry.

  16. Human otolith-ocular reflexes during off-vertical axis rotation: effect of frequency on tilt-translation ambiguity and motion sickness

    NASA Technical Reports Server (NTRS)

    Wood, Scott J.; Paloski, W. H. (Principal Investigator)

    2002-01-01

    The purpose of this study was to examine how the modulation of tilt and translation otolith-ocular responses during constant velocity off-vertical axis rotation varies as a function of stimulus frequency. Eighteen human subjects were rotated in darkness about their longitudinal axis 30 degrees off-vertical at stimulus frequencies between 0.05 and 0.8 Hz. The modulation of torsion decreased while the modulation of horizontal slow phase velocity (SPV) increased with increasing frequency. It is inferred that the ambiguity of otolith afferent information is greatest in the frequency region where tilt (torsion) and translational (horizontal SPV) otolith-ocular responses crossover. It is postulated that the previously demonstrated peak in motion sickness susceptibility during linear accelerations around 0.3 Hz is the result of frequency segregation of ambiguous otolith information being inadequate to distinguish between tilt and translation.

  17. Human otolith-ocular reflexes during off-vertical axis rotation: effect of frequency on tilt-translation ambiguity and motion sickness

    NASA Technical Reports Server (NTRS)

    Wood, Scott J.; Paloski, W. H. (Principal Investigator)

    2002-01-01

    The purpose of this study was to examine how the modulation of tilt and translation otolith-ocular responses during constant velocity off-vertical axis rotation varies as a function of stimulus frequency. Eighteen human subjects were rotated in darkness about their longitudinal axis 30 degrees off-vertical at stimulus frequencies between 0.05 and 0.8 Hz. The modulation of torsion decreased while the modulation of horizontal slow phase velocity (SPV) increased with increasing frequency. It is inferred that the ambiguity of otolith afferent information is greatest in the frequency region where tilt (torsion) and translational (horizontal SPV) otolith-ocular responses crossover. It is postulated that the previously demonstrated peak in motion sickness susceptibility during linear accelerations around 0.3 Hz is the result of frequency segregation of ambiguous otolith information being inadequate to distinguish between tilt and translation.

  18. Vaccination for protection of retinal ganglion cells against death from glutamate cytotoxicity and ocular hypertension: Implications for glaucoma

    NASA Astrophysics Data System (ADS)

    Schori, Hadas; Kipnis, Jonathan; Yoles, Eti; Woldemussie, Elizabeth; Ruiz, Guadalupe; Wheeler, Larry A.; Schwartz, Michal

    2001-03-01

    Our group recently demonstrated that autoimmune T cells directed against central nervous system-associated myelin antigens protect neurons from secondary degeneration. We further showed that the synthetic peptide copolymer 1 (Cop-1), known to suppress experimental autoimmune encephalomyelitis, can be safely substituted for the natural myelin antigen in both passive and active immunization for neuroprotection of the injured optic nerve. Here we attempted to determine whether similar immunizations are protective from retinal ganglion cell loss resulting from a direct biochemical insult caused, for example, by glutamate (a major mediator of degeneration in acute and chronic optic nerve insults) and in a rat model of ocular hypertension. Passive immunization with T cells reactive to myelin basic protein or active immunization with myelin oligodendrocyte glycoprotein-derived peptide, although neuroprotective after optic nerve injury, was ineffective against glutamate toxicity in mice and rats. In contrast, the number of surviving retinal ganglion cells per square millimeter in glutamate-injected retinas was significantly larger in mice immunized 10 days previously with Cop-1 emulsified in complete Freund's adjuvant than in mice injected with PBS in the same adjuvant (2,133 ± 270 and 1,329 ± 121, respectively, mean ± SEM; P < 0.02). A similar pattern was observed when mice were immunized on the day of glutamate injection (1,777 ± 101 compared with 1,414 ± 36; P <0.05), but not when they were immunized 48h later. These findings suggest that protection from glutamate toxicity requires reinforcement of the immune system by antigens that are different from those associated with myelin. The use of Cop-1 apparently circumvents this antigen specificity barrier. In the rat ocular hypertension model, which simulates glaucoma, immunization with Cop-1 significantly reduced the retinal ganglion cell loss from 27.8%±6.8% to 4.3%±1.6%, without affecting the intraocular pressure

  19. Carotid Stenosis and Ocular Blood Pressure Modelling

    PubMed Central

    Jullian, M.; Kinsner, W.

    1984-01-01

    A model of the human carotid vascular system was developed to study the effects of carotid stenosis on ocular blood pressure and ocular pulse waveform. The model incorporates a non-linear element representing a stenosis. A state variable representation of a reduced model is used in a computer simulation. Results show that carotid stenosis as low as 20% are detectable in the ocular blood pressure waveform.

  20. Ocular dispersion

    NASA Astrophysics Data System (ADS)

    Hammer, Daniel X.; Noojin, Gary D.; Thomas, Robert J.; Stolarski, David J.; Rockwell, Benjamin A.; Welch, Ashley J.

    1999-06-01

    Spectrally resolved white-light interferometry (SRWLI) was used to measure the wavelength dependence of refractive index (i.e., dispersion) for various ocular components. The accuracy of the technique was assessed by measurement of fused silica and water, the refractive indices of which have been measured at several different wavelengths. The dispersion of bovine and rabbit aqueous and vitreous humor was measured from 400 to 1100 nm. Also, the dispersion was measured from 400 to 700 nm for aqueous and vitreous humor extracted from goat and rhesus monkey eyes. For the humors, the dispersion did not deviate significantly from water. In an additional experiment, the dispersion of aqueous and vitreous humor that had aged up to a month was compared to freshly harvested material. No difference was found between the fresh and aged media. An unsuccessful attempt was also made to use the technique for dispersion measurement of bovine cornea and lens. Future refinement may allow measurement of the dispersion of cornea and lens across the entire visible and near-infrared wavelength band. The principles of white- light interferometry including image analysis, measurement accuracy, and limitations of the technique, are discussed. In addition, alternate techniques and previous measurements of ocular dispersion are reviewed.

  1. Effect of cord blood serum on ex vivo human limbal epithelial cell culture.

    PubMed

    Chakraborty, Anindita; Dutta, Jayanta; Das, Sumantra; Datta, Himadri

    2012-12-01

    Limbal cell transplantation is an efficacious procedure for rehabilitation of visual acuity in patients with severe ocular surface disorders. Cultivation of limbal epithelial stem cell with fetal bovine serum for transplantation has been a promising treatment for reconstructing the ocular surface in severe limbal stem cell deficiency caused by Steven Johnson syndrome, chemical or thermal injury. This technique of "cell therapy" has been accepted worldwide but the cost of cultivating the cells for transplantation is high. The objective of this study was to investigate the effect of cord blood serum in place of fetal bovine serum on the growth of human limbal epithelial cell culture. Our group has experimented with human cord blood serum which was obtained free of cost from willing donors. The use of human cord blood serum in place of fetal bovine serum for ex vivo culture of limbal stem cell has helped us in reducing the cost of culture. Fresh human limbal tissues from donor cadavers were cultured on intact and denuded amniotic membrane. Cells were proliferated in vitro with cell culture media containing human cord blood serum. Reverse transcription-polymerase chain reaction and immunofluorescence cytochemistry of cultured human limbal epithelial stem cell was done for characterization of the cells.

  2. Mechanisms of interaction of laser radiation with ocular tissues: implications for human exposure limits

    NASA Astrophysics Data System (ADS)

    Sliney, D. H.

    1981-12-01

    Many investigations of laser injury to the eye have been carried out over the past 15 years in order to set standards for safe exposure of the human eye to laser radiation. A review of this extensive body of mainly experimental data suggests that there are at least three dominant mechanisms of injury which are well accepted. However, other effects cannot be ruled out. In particular, several results suggest that the time evolution of injury and repair processes as well as the physical aspects of the interaction of biological tissue with optical radiation must be considered.

  3. Dose-response relationship for light intensity and ocular and electroencephalographic correlates of human alertness

    NASA Technical Reports Server (NTRS)

    Cajochen, C.; Zeitzer, J. M.; Czeisler, C. A.; Dijk, D. J.

    2000-01-01

    Light can elicit both circadian and acute physiological responses in humans. In a dose response protocol men and women were exposed to illuminances ranging from 3 to 9100 lux for 6.5 h during the early biological night after they had been exposed to <3 lux for several hours. Light exerted an acute alerting response as assessed by a reduction in the incidence of slow-eye movements, a reduction of EEG activity in the theta-alpha frequencies (power density in the 5-9 Hz range) as well as a reduction in self-reported sleepiness. This alerting response was positively correlated with the degree of melatonin suppression by light. In accordance with the dose response function for circadian resetting and melatonin suppression, the responses of all three indices of alertness to variations in illuminance were consistent with a logistic dose response curve. Half of the maximum alerting response to bright light of 9100 lux was obtained with room light of approximately 100 lux. This sensitivity to light indicates that variations in illuminance within the range of typical, ambient, room light (90-180 lux) can have a significant impact on subjective alertness and its electrophysiologic concomitants in humans during the early biological night.

  4. Dose-response relationship for light intensity and ocular and electroencephalographic correlates of human alertness.

    PubMed

    Cajochen, C; Zeitzer, J M; Czeisler, C A; Dijk, D J

    2000-10-01

    Light can elicit both circadian and acute physiological responses in humans. In a dose response protocol men and women were exposed to illuminances ranging from 3 to 9100 lux for 6.5 h during the early biological night after they had been exposed to <3 lux for several hours. Light exerted an acute alerting response as assessed by a reduction in the incidence of slow-eye movements, a reduction of EEG activity in the theta-alpha frequencies (power density in the 5-9 Hz range) as well as a reduction in self-reported sleepiness. This alerting response was positively correlated with the degree of melatonin suppression by light. In accordance with the dose response function for circadian resetting and melatonin suppression, the responses of all three indices of alertness to variations in illuminance were consistent with a logistic dose response curve. Half of the maximum alerting response to bright light of 9100 lux was obtained with room light of approximately 100 lux. This sensitivity to light indicates that variations in illuminance within the range of typical, ambient, room light (90-180 lux) can have a significant impact on subjective alertness and its electrophysiologic concomitants in humans during the early biological night.

  5. Dose-response relationship for light intensity and ocular and electroencephalographic correlates of human alertness

    NASA Technical Reports Server (NTRS)

    Cajochen, C.; Zeitzer, J. M.; Czeisler, C. A.; Dijk, D. J.

    2000-01-01

    Light can elicit both circadian and acute physiological responses in humans. In a dose response protocol men and women were exposed to illuminances ranging from 3 to 9100 lux for 6.5 h during the early biological night after they had been exposed to <3 lux for several hours. Light exerted an acute alerting response as assessed by a reduction in the incidence of slow-eye movements, a reduction of EEG activity in the theta-alpha frequencies (power density in the 5-9 Hz range) as well as a reduction in self-reported sleepiness. This alerting response was positively correlated with the degree of melatonin suppression by light. In accordance with the dose response function for circadian resetting and melatonin suppression, the responses of all three indices of alertness to variations in illuminance were consistent with a logistic dose response curve. Half of the maximum alerting response to bright light of 9100 lux was obtained with room light of approximately 100 lux. This sensitivity to light indicates that variations in illuminance within the range of typical, ambient, room light (90-180 lux) can have a significant impact on subjective alertness and its electrophysiologic concomitants in humans during the early biological night.

  6. Comparative assessment of the cytotoxicity of six anti-inflammatory eyedrops in four cultured ocular surface cell lines, as determined by cell viability scores

    PubMed Central

    Ayaki, Masahiko; Iwasawa, Atsuo; Niwano, Yoshimi

    2012-01-01

    Purpose Anti-inflammatory eyedrops are often used in the treatment of corneal epithelial disorders. In the present study, we evaluated the cytotoxicity of six anti-inflammatory eyedrops in four ocular surface cell lines. Methods The cytotoxicity of six commercially available anti-inflammatory ophthalmic solutions (ie, diclofenac, bromfenac, pranoprofen, betamethasone, and fluoromethorone) was assessed in three corneal cell lines and one conjunctival cell line. Cell viability was determined by the 3-(4,5-dimethyl-2 thiazoyl)-2,5-diphenyl-2H-tetrazolium bromide and neutral red assays after exposing the cells to 10, 30, and 60 minutes of onefold, twofold, and tenfold dilutions of the drugs. Cytotoxicity was compared using the cell viability score (CVS), an integrated cytotoxic parameter that takes various factors into account, such as dilution by tear fluid or concentration by evaporation, drug exposure time, and ocular surface cell type. Results Based on the CVS scores, the order of the anti-inflammatory eyedrops tested from least to most cytotoxic, with the active ingredient %CVS50, and %CVS40/80 for each solution given in parentheses, was as follows: Rinderon® (betamethasone, 100%, 100%) >0.02% Flumethoron® (fluoromethorone, 68%, 22%) = 0.1% Flumethoron® (fluoromethorone, 76%, 22%) >Bronuck® (0.1% bromfenac, 53%, −8%) = Diclod® (0.1% diclofenac, 44%, −15%) = Niflan® (pranoprofen, 50%, −19%). Rinderon® exhibited the least toxicity of all the anti-inflammatory eyedrops tested. Eyedrops containing non-steroidal anti-inflammatory drugs exhibited greater cytotoxicity than those containing steroids with benzalkonium at comparable concentrations. Concentration was the most significant factor affecting cell viability. Conclusion The cytotoxicity of the anti-inflammatory eyedrops evaluated in the present study depended on both the pharmaceutical components and preservatives. The CVS is a concise indicator of drug cytotoxicity. PMID:23185116

  7. Optical density of the aging human ocular media in the visible and the UV

    NASA Astrophysics Data System (ADS)

    van de Kraats, Jan; van Norren, Dirk

    2007-07-01

    We analyzed the literature on the absorption in the young and aging human eye media. Five templates were derived to provide an adequate description of the spectra from 300 to 700 nm for the lens, cornea, aqueous, and vitreous. Two templates were found in all media. They stand for Rayleigh scatter and the absorbance of tryptophan. Three additional templates for the lens represent absorbance in kynurenine derivatives, such as 3-hydroxykynurenine glucoside (3HKG), and absorbance in two substances found at older age. Except for Rayleigh scatter, all templates have a Gaussian shape. Aging-trend functions were derived that show a linear slope on an age-squared scale. The result can be used to correct for media losses in visual perception tasks, in fundus reflectometry, and in studies on light damage.

  8. Horizontal otolith-ocular responses in humans after unilateral vestibular deafferentation.

    PubMed

    Lempert, T; Gianna, C; Brookes, G; Bronstein, A; Gresty, M

    1998-02-01

    We studied horizontal eye movements evoked by lateral whole body translation in nine patients who underwent vestibular nerve section. Preoperatively, all had preserved caloric function on both sides. Testing was performed before, 1 week and 6-10 weeks after surgery. Patients were seated upright in an electrically powered car running on a linear track. The car executed acceleration steps of 0.24 g, randomly to the left and right in the dark. The normal response consisted of a bidirectionally symmetrical nystagmus with compensatory slow phases. Response asymmetry of the slow-phase velocity of the desaccaded and averaged eye position signal was less than 13% in normals (n = 21). Before surgery, patients' responses were mostly symmetrical. Postoperatively, responses were diminished or absent with head acceleration towards the operated ear in all patients, causing a marked asymmetry which averaged 56% after correction for spontaneous nystagmus. On follow-up, responses regained symmetry. Thus, early after vestibular nerve section, a single utricle produces a normal LVOR only with ipsilateral head translation. Therefore, afferents for the LVOR seem to originate from the mid-lateral area of the macula, where hair cells are stimulated in their on-direction during ipsilateral head translation. Compensation may depend on recovery of the off-directional responses from lateral hair cells of the remaining utricle.

  9. Defensins and Other Antimicrobial Peptides at the Ocular Surface

    PubMed Central

    McDermott, Alison M.

    2006-01-01

    Although constantly exposed to the environment and “foreign bodies” such as contact lenses and unwashed fingertips, the ocular surface succumbs to infection relatively infrequently. This is, in large part, due to a very active and robust innate immune response mounted at the ocular surface. Studies over the past 20 years have revealed that small peptides with antimicrobial activity are a major component of the human innate immune response system. The ocular surface is no exception, with peptides of the defensin and cathelicidin families being detected in the tear film and secreted by corneal and conjunctival epithelial cells. There is also much evidence to suggest that the role of some antimicrobial peptides is not restricted to direct killing of pathogens, but, rather, that they function in various aspects of the immune response, including recruitment of immune cells, and through actions on dendritic cells provide a link to adaptive immunity. A role in wound healing is also supported. In this article, the properties, mechanisms of actions and functional roles of antimicrobial peptides are reviewed, with particular emphasis on the potential multifunctional roles of defensins and LL-37 (the only known human cathelicidin) at the ocular surface. PMID:17216098

  10. Cues for the control of ocular accommodation and vergence during postnatal human development

    PubMed Central

    Bharadwaj, Shrikant R.; Candy, T. Rowan

    2009-01-01

    Accommodation and vergence help maintain single and focused visual experience while an object moves in depth. The relative importance of retinal blur and disparity, the primary sensory cues to accommodation and vergence, is largely unknown during development; a period when growth of the eye and head necessitate continual recalibration of egocentric space. Here we measured the developmental importance of retinal disparity in 192 typically developing subjects (1.9 months to 46 years). Subjects viewed high-contrast cartoon targets with naturalistic spatial frequency spectra while their accommodation and vergence responses were measured from both eyes using a PowerRefractor. Accommodative gain was reduced during monocular viewing relative to full binocular viewing, even though the fixating eye generated comparable tracking eye movements in the two conditions. This result was consistent across three forms of monocular occlusion. The accommodative gain was lowest in infants and only reached adult levels by 7 to 10 years of age. As expected, the gain of vergence was also reduced in monocular conditions. When 4- to 6-year-old children read 20/40-sized letters, their monocular accommodative gain reached adult-like levels. In summary, binocular viewing appears necessary under naturalistic viewing conditions to generate full accommodation and vergence responses in typically developing humans. PMID:19146280

  11. Proteomic analysis of the soluble fraction from human corneal fibroblasts with reference to ocular transparency.

    PubMed

    Karring, Henrik; Thøgersen, Ida B; Klintworth, Gordon K; Enghild, Jan J; Møller-Pedersen, Torben

    2004-07-01

    The transparent corneal stroma contains a population of corneal fibroblasts termed keratocytes, which are interspersed between the collagen lamellae. Under normal conditions, the keratocytes are quiescent and transparent. However, after corneal injury the keratocytes become activated and transform into backscattering wound-healing fibroblasts resulting in corneal opacification. At present, the most popular hypothesis suggests that particular abundant water-soluble proteins called enzyme-crystallins are involved in maintaining corneal cellular transparency. Specifically, corneal haze development is thought to be related to low levels of cytoplasmic enzyme-crystallins in reflective corneal fibroblasts. To further investigate this hypothesis, we have used a proteomic approach to identify the most abundant water-soluble proteins in serum-cultured human corneal fibroblasts that represent an in vitro model of the reflective wound-healing keratocyte phenotype. Densitometry of one-dimensional gels revealed that no single protein isoform exceeded 5% of the total water-soluble protein fraction, which is the qualifying property of a corneal enzyme-crystallin according to the current definition. This result indicates that wound-healing corneal fibroblasts do not contain enzyme-crystallins. A total of 254 protein identifications from two-dimensional gels were performed representing 118 distinct proteins. Proteins protecting against oxidative stress and protein misfolding were prominent, suggesting that these processes may participate in the generation of cytoplasmic light-scattering from corneal fibroblasts.

  12. Transmastoid galvanic stimulation does not affect the vergence-mediated gain increase of the human angular vestibulo-ocular reflex

    PubMed Central

    Migliaccio, Americo A.; Della Santina, Charles C.; Carey, John P.

    2012-01-01

    Vergence is one of several viewing contexts that require an increase in the angular vestibular-ocular reflex (aVOR) response. A previous monkey study found that the vergence-mediated gain (eye/head velocity) increase of the aVOR was attenuated by 64% when anodic currents, which preferentially lower the activity of irregularly firing vestibular afferents, were delivered to both labyrinths. We sought to determine if there was similar evidence implicating a role for irregular afferents in the vergence-mediated gain increase of the human aVOR. Our study is based upon analysis of the aVOR evoked by head rotations, delivered passively while subjects viewed a near (15cm) or far (124cm) target and applying galvanic vestibular stimulation (GVS) via surface electrodes. We tested 12 subjects during 2–3 sessions each. Vestibular stimuli consisted of passive whole-body rotations (sinusoids from 0.05 – 3Hz and 12 – 25°/s, and transients with peak ~15°, 50°/s, 500°/s2) and head-on-body impulses (peak ~30°, 150°/s, 3000°/s2). GVS was on for 10s every 20s. All polarity combinations were tested, with emphasis on uni- and bi-lateral anodic inhibition. The average stimulus current was 5.9 ± 1.6 mA (range: 3 – 9.5 mA), vergence angle (during near-viewing) was 22.6 ± 2.8° and slow phase eye velocity caused by left anodic current stimulation with head stationary was −3.4 ± 1.1°/s, −0.2 ± 0.6°/s and 2.5 ± 1.4°/s (torsion, vertical, horizontal). No statistically significant GVS effects were observed, suggesting that surface electrode GVS has no effect on the vergence-mediated gain increase of the aVOR at the current levels (~6 mA) tolerated by most humans. We conclude that clinically practical transmastoid GVS does not effectively silence irregular afferents and hypothesize that currents > 10mA are needed to reproduce the monkey results. PMID:23150093

  13. Ultraviolet transmittance of human limbal epithelial cells cultured on human amniotic membranes.

    PubMed

    Mimura, Tatsuya; Yokoo, Seiichi; Kaji, Yuichi; Usui, Tomohiko; Yamagam, Satoru; Ono, Kyoko; Araie, Makoto; Amano, Shiro

    2005-07-01

    To evaluate ultraviolet (UV) A and B transmittance by human limbal epithelial cells cultured on human amniotic membranes. Human limbal epithelial cells were taken from the limbus of donor corneas and were cultured on human amniotic membranes with inactivated 3T3 fibroblasts for 2 to 4 weeks. Then, the cultured cells were examined histologically. Next, cells from different culture periods were irradiated with UV-A (365 nm) or UV-B (302 nm) at energy levels ranging from 50 to 800 microW/cm2, and UV transmittance was measured with a UV light meter. Histological examination revealed a monolayer of corneal epithelial cells on the amniotic membrane after 2 weeks of culture, and a layer of 3-4 cells was formed after 4 weeks. Transmittance of UV-A and UV-B was highest by the amniotic membrane alone, followed in decreasing order by limbal epithelial cells cultured on amniotic membranes for 2 weeks, 3 weeks, and 4 weeks. These results indicate that UV absorbance increases in proportion to the number of limbal epithelial cell layers in cultures on amniotic membranes. Limbal epithelial cells may need to be cultured until 3-4 layers are formed in order to prevent ocular damage by UV light after transplantation.

  14. Role of CD8+ T cells and lymphoid dendritic cells in protection from ocular herpes simplex virus 1 challenge in immunized mice.

    PubMed

    Matundan, Harry; Mott, Kevin R; Ghiasi, Homayon

    2014-07-01

    The development of immunization strategies to protect against ocular infection with herpes simplex virus 1 (HSV-1) must address the issue of the effects of the strategy on the establishment of latency in the trigeminal ganglia (TG). It is the reactivation of this latent virus that can cause recurrent disease and corneal scarring. CD8(+) T cells and dendritic cells (DCs) have been implicated in the establishment and maintenance of latency through several lines of inquiry. The objective of the current study was to use CD8α(-/-) and CD8β(-/-) mice to further evaluate the contributions of CD8(+) T cells and the CD8α(+) and CD8α(-) subpopulations of DCs to the protection afforded against ocular infection by immunization against HSV-1 and their potential to increase latency. Neutralizing antibody titers were similar in immunized CD8α(-/-), CD8β(-/-), and wild-type (WT) mice, as was virus replication in the eye. However, on day 3 postinfection (p.i.), the copy number of HSV-1 glycoprotein B (gB) was higher in the corneas and TG of CD8α(-/-) mice than those of WT mice, whereas on day 5 p.i. it was lower. As would be anticipated, the lack of CD8α(+) or CD8β(+) cells affected the levels of type I and type II interferon transcripts, but the effects were markedly time dependent and tissue specific. The levels of latent virus in the TG, as estimated by measurement of LAT transcripts and in vitro explant reactivation assays, were lower in the immunized, ocularly challenged CD8α(-/-) and WT mice than in their CD8β(-/-) counterparts. Immunization reduced the expression of PD-1, a marker of T-cell exhaustion, in the TG of ocularly challenged mice, and mock-immunized CD8α(-/-) mice had lower levels of PD-1 expression and latency than mock-immunized WT or CD8β(-/-) mice. The expansion of the CD8α(-) subpopulation of DCs through injection of WT mice with granulocyte-macrophage colony-stimulating factor (GM-CSF) DNA reduced the amount of latency and PD-1 expression in the

  15. Rho GTPases and Regulation of Cell Migration and Polarization in Human Corneal Epithelial Cells

    PubMed Central

    Hou, Aihua; Toh, Li Xian; Gan, Kah Hui; Lee, Khee Jin Ryan; Manser, Edward; Tong, Louis

    2013-01-01

    Purpose Epithelial cell migration is required for regeneration of tissues and can be defective in a number of ocular surface diseases. This study aimed to determine the expression pattern of Rho family small G-proteins in human corneal epithelial cells to test their requirement in directional cell migration. Methods Rho family small G-protein expression was assessed by reverse transcription-polymerase chain reaction. Dominant-inhibitory constructs encoding Rho proteins or Rho protein targeting small interfering RNA were transfected into human corneal epithelial large T antigen cells, and wound closure rate were evaluated by scratch wounding assay, and a complementary non-traumatic cell migration assay. Immunofluorescence staining was performed to study cell polarization and to assess Cdc42 downstream effector. Results Cdc42, Chp, Rac1, RhoA, TC10 and TCL were expressed in human corneal epithelial cells. Among them, Cdc42 and TCL were found to significantly affect cell migration in monolayer scratch assays. These results were confirmed through the use of validated siRNAs directed to Cdc42 and TCL. Scramble siRNA transfected cells had high percentage of polarized cells than Cdc42 or TCL siRNA transfected cells at the wound edge. We showed that the Cdc42-specific effector p21-activated kinase 4 localized predominantly to cell-cell junctions in cell monolayers, but failed to translocate to the leading edge in Cdc42 siRNA transfected cells after monolayer wounding. Conclusion Rho proteins expressed in cultured human corneal epithelial cells, and Cdc42, TCL facilitate two-dimensional cell migration in-vitro. Although silencing of Cdc42 and TCL did not noticeably affect the appearance of cell adhesions at the leading edge, the slower migration of these cells indicates both GTP-binding proteins play important roles in promoting cell movement of human corneal epithelial cells. PMID:24130842

  16. 21 CFR 886.1040 - Ocular esthesiometer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ocular esthesiometer. 886.1040 Section 886.1040 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED.... An ocular esthesiometer is a device, such as a single-hair brush, intended to touch the cornea to...

  17. 21 CFR 886.1040 - Ocular esthesiometer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ocular esthesiometer. 886.1040 Section 886.1040 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED.... An ocular esthesiometer is a device, such as a single-hair brush, intended to touch the cornea to...

  18. 21 CFR 882.1790 - Ocular plethysmograph.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ocular plethysmograph. 882.1790 Section 882.1790 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... and Drug Administration on or before September 21, 2004, for any ocular plethysmograph that was...

  19. 21 CFR 882.1790 - Ocular plethysmograph.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ocular plethysmograph. 882.1790 Section 882.1790 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... and Drug Administration on or before September 21, 2004, for any ocular plethysmograph that was...

  20. 21 CFR 886.1040 - Ocular esthesiometer.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ocular esthesiometer. 886.1040 Section 886.1040 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED.... An ocular esthesiometer is a device, such as a single-hair brush, intended to touch the cornea...

  1. 21 CFR 886.1040 - Ocular esthesiometer.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Ocular esthesiometer. 886.1040 Section 886.1040 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED.... An ocular esthesiometer is a device, such as a single-hair brush, intended to touch the cornea...

  2. 21 CFR 886.1040 - Ocular esthesiometer.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Ocular esthesiometer. 886.1040 Section 886.1040 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED.... An ocular esthesiometer is a device, such as a single-hair brush, intended to touch the cornea...

  3. Ocular presentation of natural killer/T-cell lymphoma in a Caucasian man.

    PubMed

    Hughes, Emily; Fogarty, Helen; Fortune, Anne; Keegan, David

    2016-04-26

    Natural killer/T-cell (NK/T-cell) lymphoma-nasal subtype, is a rare form of non-Hodgkin's lymphoma, most common in South East Asia, and can have an ophthalmological presentation. This report describes a 51-year-old Caucasian man with uveitis, recurrent retinal detachment and paraneoplastic features subsequently diagnosed as NK/T-cell lymphoma.

  4. Phototoxicity and cytotoxicity of fullerol in human lens epithelial cells

    SciTech Connect

    Roberts, Joan E. Wielgus, Albert R. Boyes, William K. Andley, Usha Chignell, Colin F.

    2008-04-01

    The water-soluble, hydroxylated fullerene [fullerol, nano-C{sub 60}(OH){sub 22-26}] has several clinical applications including use as a drug carrier to bypass the blood ocular barriers. We have assessed fullerol's potential ocular toxicity by measuring its cytotoxicity and phototoxicity induced by UVA and visible light in vitro with human lens epithelial cells (HLE B-3). Accumulation of nano-C{sub 60}(OH){sub 22-26} in the cells was confirmed spectrophotometrically at 405 nm and cell viability estimated using MTS and LDH assays. Fullerol was cytotoxic to HLE B-3 cells maintained in the dark at concentrations higher than 20 {mu}M. Exposure to either UVA or visible light in the presence of > 5 {mu}M fullerol-induced phototoxic damage. When cells were pretreated with non-toxic antioxidants: 20 {mu}M lutein, 1 mM N-acetyl cysteine, or 1 mM L-ascorbic acid prior to irradiation, only the singlet oxygen quencher-lutein significantly protected against fullerol photodamage. Apoptosis was observed in lens cells treated with fullerol whether or not the cells were irradiated, in the order UVA > visible light > dark. Dynamic light scattering (DLS) showed that in the presence of the endogenous lens protein {alpha}-crystallin, large aggregates of fullerol were reduced. In conclusion, fullerol is both cytotoxic and phototoxic to human lens epithelial cells. Although the acute toxicity of water-soluble nano-C{sub 60}(OH){sub 22-26} is low, these compounds are retained in the body for long periods, raising concern for their chronic toxic effect. Before fullerols are used to deliver drugs to the eye, they should be tested for photo- and cytotoxicity in vivo.

  5. Ocular anatomy, ganglion cell distribution and retinal resolution of a killer whale (Orcinus orca).

    PubMed

    Mass, Alla M; Supin, Alexander Y; Abramov, Andrey V; Mukhametov, Lev M; Rozanova, Elena I

    2013-01-01

    Retinal topography, cell density and sizes of ganglion cells in the killer whale (Orcinus orca) were analyzed in retinal whole mounts stained with cresyl violet. A distinctive feature of the killer whale's retina is the large size of ganglion cells and low cell density compared to terrestrial mammals. The ganglion cell diameter ranged from 8 to 100 µm, with the majority of cells within a range of 20-40 µm. The topographic distribution of ganglion cells displayed two spots of high cell density located in the temporal and nasal quadrants, 20 mm from the optic disk. The high-density areas were connected by a horizontal belt-like area passing below the optic disk of the retina. Peak cell densities in these areas were evaluated. Mean peak cell densities were 334 and 288 cells/mm(2) in the temporal and nasal high-density areas, respectively. With a posterior nodal distance of 19.5 mm, these high-density data predict a retinal resolution of 9.6' (3.1 cycles/deg.) and 12.6' (2.4 cycles/deg.) in the temporal and nasal areas, respectively, in water. Copyright © 2012 S. Karger AG, Basel.

  6. Genome engineering in human cells.

    PubMed

    Song, Minjung; Kim, Young-Hoon; Kim, Jin-Soo; Kim, Hyongbum

    2014-01-01

    Genome editing in human cells is of great value in research, medicine, and biotechnology. Programmable nucleases including zinc-finger nucleases, transcription activator-like effector nucleases, and RNA-guided engineered nucleases recognize a specific target sequence and make a double-strand break at that site, which can result in gene disruption, gene insertion, gene correction, or chromosomal rearrangements. The target sequence complexities of these programmable nucleases are higher than 3.2 mega base pairs, the size of the haploid human genome. Here, we briefly introduce the structure of the human genome and the characteristics of each programmable nuclease, and review their applications in human cells including pluripotent stem cells. In addition, we discuss various delivery methods for nucleases, programmable nickases, and enrichment of gene-edited human cells, all of which facilitate efficient and precise genome editing in human cells.

  7. Overview of ocular allergy treatment.

    PubMed

    Friedlaender, M

    2001-07-01

    A plethora of drugs is available for the treatment of ocular allergy. Traditional treatment includes antihistamine and antihistamine/vasoconstrictor combination eyedrops. These drugs are useful, safe, and readily available. Mast cell stabilizers are safe, effective, and an important component of antiallergic therapy. Nonsteroidal anti-inflammatory drugs also have antiallergic effects. In recent years, drugs with multiple mechanisms of action have proven to be effective antiallergics. These drugs often have mast cell stabilizing, antihistaminic, and anti-inflammatory properties. Corticosteroids are considered to be more potent than other antiallergic drugs, and modifications in their molecular structures have made certain corticosteroids suitable for the treatment of ocular allergy.

  8. Topical Delivery of Anti-VEGF Drugs to the Ocular Posterior Segment Using Cell-Penetrating Peptides.

    PubMed

    de Cogan, Felicity; Hill, Lisa J; Lynch, Aisling; Morgan-Warren, Peter J; Lechner, Judith; Berwick, Matthew R; Peacock, Anna F A; Chen, Mei; Scott, Robert A H; Xu, Heping; Logan, Ann

    2017-05-01

    To evaluate the efficacy of anti-VEGF agents for treating choroidal neovascularization (CNV) when delivered topically using novel cell-penetrating peptides (CPPs) compared with delivery by intravitreal (ivit) injection. CPP toxicity was investigated in cell cultures. Ivit concentrations of ranibizumab and bevacizumab after topical administration were measured using ELISA. The biological efficacy of topical anti-VEGF + CPP complexes was compared with ivit anti-VEGF injections using an established model of CNV. CPPs were nontoxic in vitro. In vivo, after topical eye drop delivery, CPPs were present in the rat anterior chamber within 6 minutes. A single application of CPP + bevacizumab eye drop delivered clinically relevant concentrations of bevacizumab to the posterior chamber of the rat eye in vivo. Similarly, clinically relevant levels of CPP + ranibizumab and CPP + bevacizumab were detected in the porcine vitreous and retina ex vivo. In an established model of CNV, mice treated with either a single ivit injection of anti-VEGF, twice daily CPP + anti-VEGF eye drops or daily dexamethasone gavage for 10 days all had significantly reduced areas of CNV when compared with lasered eyes without treatment. CPPs are nontoxic to ocular cells and can be used to deliver therapeutically relevant doses of ranibizumab and bevacizumab by eye drop to the posterior segment of mouse, rat, and pig eyes. The CPP + anti-VEGF drug complexes were cleared from the retina within 24 hours, suggesting a daily eye drop dosing regimen. Daily, topically delivered anti-VEGF with CPP was as efficacious as a single ivit injection of anti-VEGF in reducing areas of CNV in vivo.

  9. Therapeutic Effect of Human Adipose Tissue-Derived Mesenchymal Stem Cells in Experimental Corneal Failure Due to Limbal Stem Cell Niche Damage.

    PubMed

    Galindo, Sara; Herreras, José M; López-Paniagua, Marina; Rey, Esther; de la Mata, Ana; Plata-Cordero, María; Calonge, Margarita; Nieto-Miguel, Teresa

    2017-10-01

    Limbal stem cells are responsible for the continuous renewal of the corneal epithelium. The destruction or dysfunction of these stem cells or their niche induces limbal stem cell deficiency (LSCD) leading to visual loss, chronic pain, and inflammation of the ocular surface. To restore the ocular surface in cases of bilateral LSCD, an extraocular source of stem cells is needed to avoid dependence on allogeneic limbal stem cells that are difficult to obtain, isolate, and culture. The aim of this work was to test the tolerance and the efficacy of human adipose tissue-derived mesenchymal stem cells (hAT-MSCs) to regenerate the ocular surface in two experimental models of LSCD that closely resemble different severity grades of the human pathology. hAT-MSCs transplanted to the ocular surface of the partial and total LSCD models developed in rabbits were well tolerated, migrated to inflamed tissues, reduced inflammation, and restrained the evolution of corneal neovascularization and corneal opacity. The expression profile of the corneal epithelial cell markers CK3 and E-cadherin, and the limbal epithelial cell markers CK15 and p63 was lost in the LSCD models, but was partially recovered after hAT-MSC transplantation. For the first time, we demonstrated that hAT-MSCs improve corneal and limbal epithelial phenotypes in animal LSCD models. These results support the potential use of hAT-MSCs as a novel treatment of ocular surface failure due to LSCD. hAT-MSCs represent an available, non-immunogenic source of stem cells that may provide therapeutic benefits in addition to reduce health care expenses. Stem Cells 2017;35:2160-2174. © 2017 AlphaMed Press.

  10. Advances in corneal stem-cell transplantation in rabbits with severe ocular alkali burns.

    PubMed

    Luengo Gimeno, Federico; Lavigne, Victoria; Gatto, Silvia; Croxatto, J Oscar; Correa, Laura; Gallo, Juan E

    2007-11-01

    To evaluate the efficacy of autologous corneal epithelial sheet implantation in restoring transparency of rabbit corneas severely injured by alkaline and the effect of photocoagulation in arresting corneal neovessel ingrowth. Ophthalmology Department, School of Biomedical Sciences, Universidad Austral, Buenos Aires, Argentina. Limbal stem-cell deficiency (LSCD) was induced in 14 rabbits by alkali burns. A limbal cell biopsy was done in the contralateral eye, and the cells were cultured on a fibroblast feeder layer grown on autologous clotted platelet-poor plasma or commercial fibrin for 21 days. Anterior keratectomy was followed by suturing corneal cell sheets over the stroma. If regrowth of vessels occurred, argon laser photocoagulation was applied to them. Rabbits were killed at 30, 60, 90, 180, and 360 days and the corneas processed for histopathology and inmunohistochemistry. A small (2.5 mm(2)) limbal biopsy achieved stem-cell replication in vitro. Corneal clarity and epithelial defects evolved with a trend toward improvement. There was a significant reduction in corneal neovascularization. Histology showed a multilayered stratified epithelium including several epithelial-like cells with clear cytoplasm in the deepest part. There were no signs of intraepithelial mucin cells on the implanted corneas. Immunohistochemical results showed expression of cytokeratins 3 and 12 in the central corneal epithelium and an absence of cytokeratin 19. Autologous limbal epithelial cell transplantation improved the corneal surface in eyes with LSCD. Photocoagulation of neovessel ingrowth was effective over the 1-year follow-up. Results may facilitate the application of this technique in patients.

  11. Ocular sensitization of mice by live (but not irradiated) Chlamydia trachomatis serovar A

    SciTech Connect

    Colley, D.G.; Goodman, T.G.; Barsoum, I.S.

    1986-10-01

    Ocular exposure of mice to live elementary bodies of Chlamydia trachomatis serovar A results in immunological sensitization of the mice. This reactivity is manifested by the development of early (5 h) and delayed-type (24 h) dermal reactivity and serovar-specific antibody formation against either live or irradiated (100 kilorads) elementary bodies. Parallel ocular exposure of mice to irradiated elementary bodies does not result in this sensitization. The early and late dermal immune responses induced by ocular exposure to live organisms can be transferred to unexposed mice by serum and lymphoid cell transfers, respectively. It appears that successful murine ocular sensitization by human C. trachomatis serovar A elementary bodies is an ability manifested by live organisms and not by inactivated but antigenic organisms.

  12. Ocular rigidity, ocular pulse amplitude, and pulsatile ocular blood flow: the effect of intraocular pressure.

    PubMed

    Dastiridou, Anna I; Ginis, Harilaos S; De Brouwere, Dirk; Tsilimbaris, Miltiadis K; Pallikaris, Ioannis G

    2009-12-01

    The purpose of this study was to characterize the pressure-volume relation in the living human eye, measure the ocular pulse amplitude (OPA), and calculate the corresponding pulsatile ocular blood flow (POBF) in a range of clinically relevant IOP levels. Fifty patients with cataract (50 eyes) were enrolled in the study. After cannulation of the anterior chamber, a computer-controlled device for the intraoperative measurement and control of IOP was used to artificially increase the IOP in a stepping procedure from 15 to 40 mm Hg. The IOP was continuously recorded for 2 seconds after each infusion step. The pressure-volume relation was approximated with an exponential fit, and the ocular rigidity coefficient was computed. OPA, pulse volume (PV), and POBF were measured from the continuous IOP recordings. The average rigidity coefficient was 0.0224 microL(-1) (SD 0.0049). OPA increased by 91% and PV and POBF decreased by 29% and 30%, respectively, when increasing the IOP from 15 to 40 mm Hg. The OPA is positively correlated with the coefficient of ocular rigidity (r = 0.65, P < 0.01). The present results suggest a nonlinear pressure-volume relation in the living human eye characterized by an increase in rigidity at higher IOP levels. The increased OPA and decreased pulse volume relate to the decreased POBF and the increased mechanical resistance of the ocular wall at high IOP levels.

  13. Ocular sarcoidosis: new diagnostic modalities and treatment.

    PubMed

    Yang, Sung J; Salek, Sherveen; Rosenbaum, James T

    2017-09-01

    Ocular involvement in sarcoidosis is present in up to 80% of patients and is frequently manifested before diagnosis of the underlying systemic disease. Considering the therapeutic consequences, early diagnosis of the underlying disease is advantageous in patients presenting with ocular inflammation. There are several ocular findings suggestive of underlying sarcoidosis, such as granulomatous keratic precipitates, iris nodules, cells in the vitreous humor known as snowballs and snowbanks, and retinal periphlebitis. High suspicion is crucial for the diagnosis of sarcoidosis. This review on ocular sarcoidosis will mainly focus on new diagnostic and treatment modalities. Recent studies found possible new diagnostic indicators for the diagnosis of ocular sarcoidosis which include not only serum profiles but also vitreous sample analysis. Ophthalmologic imaging techniques have improved to investigate the ocular structure in detail. Results from recent uveitis clinical trials have included sarcoidosis as an underlying cause and have reported positive results. The diagnosis of ocular sarcoidosis can be challenging in some cases. High suspicion is important to diagnose ocular sarcoidosis with various laboratory and ophthalmic tools. There are many possible options for the treatment of ocular sarcoidosis including various biologic agents.

  14. Concise Review: Immunological Properties of Ocular Surface and Importance of Limbal Stem Cells for Transplantation

    PubMed Central

    Shaharuddin, Bakiah; Ahmad, Sajjad; Meeson, Annette

    2013-01-01

    Cornea transplantation has been considered to be different from other solid organ transplantation because of the assumed immune-privileged state of the anterior chamber of the eye. Three major lines of thought regarding the molecular mechanisms of immune privilege in the eye are as follows: (a) anatomical, cellular, and molecular barriers in the eye; (b) anterior chamber-associated immune deviation; and (c) immunosuppressive microenvironment in the eye. However, cornea transplants suffer allograft rejection when breached by vascularization. In recent developments, cellular corneal transplantation from cultivated limbal epithelial cells has shown impressive advances as a future therapy. The limbal stem cell niche contains stem cells that promote proliferation and migration and have immunosuppressive mechanisms to protect them from immunological reactions. Limbal stem cells are also noted to display an enhanced expression of genes for the antiapoptotic proteins, a property that is imperative for the survival of transplanted tissues. Further investigation of the molecular mechanisms regulating the immune regulation of limbal stem cells is relevant in the clinical setting to promote the survival of whole corneal and limbal stem cell transplantation. PMID:23817133

  15. Human Growth Hormone Promotes Corneal Epithelial Cell Migration in Vitro

    PubMed Central

    Ding, Juan; Wirostko, Barbara; Sullivan, David A

    2015-01-01

    Purpose Corneal wound healing is a highly regulated process that requires the proliferation and migration of epithelial cells and interactions between epithelial cells and stromal fibroblasts. Compounds that can be applied topically to the ocular surface and that have the capability of activating corneal epithelial cells to proliferate and/or migrate would be useful to promote corneal wound healing. We hypothesize that human growth hormone (HGH) will activate Signal Transducer and Activators of Transcription-5 (STAT5) signaling and promote corneal wound healing by enhancing corneal epithelial cell and fibroblast proliferation and/or migration in vitro. The purpose of this study is to test these hypotheses. Methods We studied cell signaling, proliferation and migration using an immortalized human corneal epithelial cell line and primary human corneal fibroblasts in vitro. We also examined whether insulin-like growth factor-1 (IGF-1), a hormone known to mediate many of HGH’s growth promoting actions, may play a role in this effect. Results We show that HGH activates STAT5 signaling and promotes corneal epithelial cell migration in vitro. The migratory effect requires an intact communication between corneal epithelia and fibroblasts, and is not mediated by IGF-1. Conclusion HGH may represent a topical therapeutic to promote corneal epithelial wound healing. This warrants further investigation. PMID:25782399

  16. Ocular surface tumors

    PubMed Central

    Othman, Ihab Saad

    2009-01-01

    Tumors of the conjunctiva and cornea comprise a large and varied spectrum of conditions. These tumors are grouped into two major categories of congenital and acquired lesions. The acquired lesions are further subdivided based on origin of the mass into surface epithelial, mucoepidermoid, melanocytic, vascular, fibrous, neural, histiocytic, myxoid, myogenic, lipomatous, lymphoid, leukemic, metastatic and secondary tumors. Ocular surface tumors include a variety of neoplasms originating from squamous epithelium, melanocytic tumors and lymphocytic resident cells of the conjunctival stroma. In this review, we highlight clinical features of these lesions, important diagnostic and investigative tools and standard care of management. PMID:21234217

  17. Dexamethasone induced ultrastructural changes in cultured human trabecular meshwork cells.

    PubMed

    Wilson, K; McCartney, M D; Miggans, S T; Clark, A F

    1993-09-01

    Glucocorticoid-induced ocular hypertension has been demonstrated in both animals and humans. It is possible that glucocorticoid-induced changes in trabecular meshwork (TM) cells are responsible for this hypertension. In order to elaborate further the effect of glucocorticoids on the trabecular meshwork, the ultrastructural consequences of dexamethasone (DEX) treatment were examined in three different human TM cell lines. Confluent TM cells were treated with 0.1 microM of DEX for 14 days, and then processed for light, epifluorescent microscopy or transmission electron microscopy (TEM). The effect of DEX treatment on TM cell and nuclear size was quantified using computer assisted morphometrics. Morphometric analysis showed a significant increase in both TM cell and nuclear size after 14 days of DEX treatment. Epifluorescent microscopy of rhodamine-phalloidin stained, control TM cells showed the normal arrangement of stress fibers. In contrast, DEX-treated TM cells showed unusual geodesic dome-like cross-linked actin networks. Control TM cells had the normal complement and arrangement of organelles as well as electron dense inclusions and large vacuoles. DEX-treated TM cells showed stacked arrangements of smooth and rough endoplasmic reticulum, proliferation of the Golgi apparatus, pleomorphic nuclei and increased amounts of extracellular matrix material. The DEX-induced alterations observed in the present study may be an indication of the processes that are occurring in the in vivo disease process.

  18. Association of High-Mobility Group Box-1 With Th Cell-Related Cytokines in the Vitreous of Ocular Sarcoidosis Patients.

    PubMed

    Takeuchi, Masaru; Taguchi, Manzo; Sato, Tomohito; Karasawa, Kyoko; Sakurai, Yutaka; Harimoto, Kohzou; Ito, Masataka

    2017-01-01

    High-mobility group box-1 (HMGB1) is a nonhistone DNA-binding nuclear protein released from necrotic cells, which is also secreted by activated leukocytes and acts as a primary proinflammatory cytokine. In this study, we compared vitreous HMGB1 levels in ocular sarcoidosis with those in noninflammatory vitreoretinal diseases and evaluated its association with Th cell-related and proinflammatory cytokines. The study group consisted of 24 patients with ocular sarcoidosis. The control group consisted of 27 patients with proliferative diabetic retinopathy (PDR) and 24 with idiopathic epiretinal membrane (ERM). Vitreous fluid samples were obtained at the beginning of vitrectomy. Vitreous levels of HMGB1 and IL-1β, IL-4, IL-6, IL-10, IL-17A, IL-17F, IL-21, IL-22, IL-23, IL-25, IL-31, IL-33, IFN-γ, soluble CD40 ligand (sCD40L), and TNFα were measured. High-mobility group box-1 was detected in the vitreous of 23 of 24 patients (95.8%) with ocular sarcoidosis. Mean vitreous level of HMGB1 was the highest in the sarcoidosis group, followed by the PDR and ERM groups, with significant differences between the three groups. In the sarcoidosis group, vitreous levels of IL-6, IL-10, IL-31, IFN-γ, sCD40L, and TNFα were significantly higher than those in the idiopathic ERM group, and IFN-γ and sCD40L were significantly higher than those in the PDR group. Vitreous HMGB-1 level correlated significantly with IL-10, IFN-γ, and sCD40L levels but not with IL-6, IL-17, IL-31, or TNFα levels. The vitreous level of HMGB1 is elevated in ocular sarcoidosis and is associated with vitreous levels of Th1- and regulatory T-related cytokines, but not with proinflammatory or Th17-related cytokines.

  19. Concise Review: Making Stem Cells Retinal: Methods for Deriving Retinal Pigment Epithelium and Implications for Patients With Ocular Disease.

    PubMed

    Leach, Lyndsay L; Clegg, Dennis O

    2015-08-01

    Stem cells provide a potentially unlimited source of cells for treating a plethora of human diseases. Regenerative therapies for retinal degenerative diseases are at the forefront of translation to the clinic, with stem cell-derived retinal pigment epithelium (RPE)-based treatments for age-related macular degeneration (AMD) already showing promise in human patients. Despite our expanding knowledge of stem cell biology, methods for deriving cells, including RPE have remained inefficient. Thus, there has been a push in recent years to develop more directed approaches to deriving cells for therapy. In this concise review, we summarize recent efforts that have been successful in improving RPE derivation efficiency by directing differentiation from human pluripotent stem cells using developmental cues important for normal RPE specification and maturation in vivo. In addition, potential obstacles for clinical translation are discussed. Finally, we review how derivation of RPE from human induced pluripotent stem cells (hiPSCs) provides in vitro models for studying mechanisms of retinal disease and discovering new avenues for treatment.

  20. Susceptibility of human iris stromal cells to herpes simplex virus 1 entry.

    PubMed

    Baldwin, John; Park, Paul J; Zanotti, Brian; Maus, Erika; Volin, Michael V; Shukla, Deepak; Tiwari, Vaibhav

    2013-04-01

    Ocular herpes simplex virus 1 (HSV-1) infection can lead to multiple complications, including iritis, an inflammation of the iris. Here, we use human iris stroma cells as a novel in vitro model to demonstrate HSV-1 entry and the inflammatory mediators that can damage the iris. The upregulated cytokines observed in this study provide a new understanding of the intrinsic immune mechanisms that can contribute to the onset of iritis.

  1. Unique and Analogous Functions of Aquaporin 0 for Fiber Cell Architecture and Ocular Lens Transparency

    PubMed Central

    Kumari, S. Sindhu; Eswaramoorthy, Subramaniam; Mathias, Richard T.; Varadaraj, Kulandaiappan

    2011-01-01

    Aquaporin (AQP) 1 and AQP0 water channels are expressed in lens epithelial and fiber cells, respectively, facilitating fluid circulation for nourishing the avascular lens to maintain transparency. Even though AQP0 water permeability is 40-fold less than AQP1, AQP0 is selectively expressed in the fibers. Delimited AQP0 fiber expression is attributed to a unique structural role as an adhesion protein. To validate this notion, we determined if wild type (WT) lens ultrastructure and fiber cell adhesion are different in AQP0−/−, and TgAQP1+/+/AQP0−/− mice that transgenically express AQP1 (TgAQP1) in fiber cells without AQP0 (AQP0−/−). In WT, lenses were transparent with ‘Y’ sutures. Fibers contained opposite end curvature, lateral interdigitations and hexagonal shape, and were arranged as concentric growth shells. AQP0−/− lenses were cataractous, lacked ‘Y’ sutures, ordered packing and well-defined lateral interdigitations. TgAQP1+/+/AQP0−/− lenses showed improvement in transparency and lateral interdigitations in the outer cortex while inner cortex and nuclear fibers were severely disintegrated. Transmission electron micrographs exhibited tightly packed fiber cells in WT whereas AQP0−/− and TgAQP1+/+/AQP0−/− lenses had wide extracellular spaces. Fibers were easily separable by teasing in AQP0−/− and TgAQP1+/+/AQP0−/− lenses compared to WT. Our data suggest that the increased water permeability through AQP1 does not compensate for loss of AQP0 expression in TgAQP1+/+/AQP0−/− mice. Fiber cell AQP0 expression is required to maintain their organization, which is a requisite for lens transparency. AQP0 appears necessary for cell-to-cell adhesion and thereby to minimize light scattering since in the AQP0−/− and TgAQP1+/+/AQP0−/− lenses, fiber cell disorganization was evident. PMID:21511033

  2. Carbon Nanotubes and Human Cells?

    ERIC Educational Resources Information Center

    King, G. Angela

    2005-01-01

    Single-walled carbon nanotubes that were chemically altered to be water soluble are shown to enter fibroblasts, T cells, and HL60 cells. Nanoparticles adversely affect immortalized HaCaT human keratinocyte cultures, indicating that they may enter cells.

  3. Carbon Nanotubes and Human Cells?

    ERIC Educational Resources Information Center

    King, G. Angela

    2005-01-01

    Single-walled carbon nanotubes that were chemically altered to be water soluble are shown to enter fibroblasts, T cells, and HL60 cells. Nanoparticles adversely affect immortalized HaCaT human keratinocyte cultures, indicating that they may enter cells.

  4. Ivermectin treatment of ocular onchocerciasis.

    PubMed

    Taylor, H R

    1990-01-01

    Ivermectin, a recently developed macrocyclic lactone with broad antiparasitic activity, has been shown by a series of clinical trials to be safe and effective in the treatment of human infection with Onchocerca volvulus. Although it is rapidly microfilaricidal, it does not cause a severe reaction as is seen with diethylcarbamazine treatment. In patients with onchocerciasis, a single oral dose of ivermectin (150 micrograms/Kg) repeated once a year leads to a marked reduction in skin microfilaria counts and ocular involvement, although ivermectin has no known long-lasting effects on the adult worms. With treatment there is no significant exacerbation of either anterior or posterior segment eye disease even in those with severe ocular disease. Treatment leads to a marked and prolonged improvement in ocular status. Because of its safety and efficacy, ivermectin can be used on a mass scale and promises to revolutionize the treatment of onchocerciasis.

  5. The Effect of Silica Nanoparticles on Human Corneal Epithelial Cells

    PubMed Central

    Park, Joo-Hee; Jeong, Hyejoong; Hong, Jinkee; Chang, Minwook; Kim, Martha; Chuck, Roy S.; Lee, Jimmy K.; Park, Choul-Yong

    2016-01-01

    Ocular drug delivery is an interesting field in current research. Silica nanoparticles (SiNPs) are promising drug carriers for ophthalmic drug delivery. However, little is known about the toxicity of SiNPs on ocular surface cells such as human corneal epithelial cells (HCECs). In this study, we evaluated the cytotoxicity induced by 50, 100 and 150 nm sizes of SiNPs on cultured HCECs for up to 48 hours. SiNPs were up-taken by HCECs inside cytoplasmic vacuoles. Cellular reactive oxygen species generation was mildly elevated, dose dependently, with SiNPs, but no significant decrease of cellular viability was observed up to concentrations of 100 μg/ml for three different sized SiNPs. Western blot assays revealed that both cellular autophagy and mammalian target of rapamycin (mTOR) pathways were activated with the addition of SiNPs. Our findings suggested that 50, 100 and 150 nm sized SiNPs did not induce significant cytotoxicity in cultured HCECs. PMID:27876873

  6. Nonhuman Primate Ocular Biometry

    PubMed Central

    Augusteyn, Robert C.; Maceo Heilman, Bianca; Ho, Arthur; Parel, Jean-Marie

    2016-01-01

    Purpose To examine ocular growth in nonhuman primates (NHPs) from measurements on ex vivo eyes. Methods We obtained NHP eyes from animals that had been killed as part of other studies or because of health-related issues. Digital calipers were used to measure the horizontal, vertical, and anteroposterior globe diameters as well as corneal horizontal and vertical diameters of excised globes from 98 hamadryas baboons, 551 cynomolgus monkeys, and 112 rhesus monkeys, at ages ranging from 23 to 360 months. Isolated lens sagittal thickness and equatorial diameter were measured by shadowphotogrammetry. Wet and fixed dry weights were obtained for lenses. Results Nonhuman primate globe growth continues throughout life, slowing toward an asymptotic maximum. The final globe size scales with negative allometry to adult body size. Corneal growth ceases at around 20 months. Lens diameter increases but thickness decreases with increasing age. Nonhuman primate lens wet and dry weight accumulation is monophasic, continuing throughout life toward asymptotic maxima. The dry/wet weight ratio reaches a maximum of 0.33. Conclusions Nonhuman primate ocular globe and lens growth differ in several respects from those in humans. Although age-related losses of lens power and accommodative amplitude are similar, lens growth and properties are different indicating care should be taken in extrapolating NHP observations to the study of human accommodation. PMID:26780314

  7. Purinergic receptors in ocular inflammation.

    PubMed

    Guzman-Aranguez, Ana; Gasull, Xavier; Diebold, Yolanda; Pintor, Jesús

    2014-01-01

    Inflammation is a complex process that implies the interaction between cells and molecular mediators, which, when not properly "tuned," can lead to disease. When inflammation affects the eye, it can produce severe disorders affecting the superficial and internal parts of the visual organ. The nucleoside adenosine and nucleotides including adenine mononucleotides like ADP and ATP and dinucleotides such as P(1),P(4)-diadenosine tetraphosphate (Ap4A), and P(1),P(5)-diadenosine pentaphosphate (Ap5A) are present in different ocular locations and therefore they may contribute/modulate inflammatory processes. Adenosine receptors, in particular A2A adenosine receptors, present anti-inflammatory action in acute and chronic retinal inflammation. Regarding the A3 receptor, selective agonists like N(6)-(3-iodobenzyl)-5'-N-methylcarboxamidoadenosine (CF101) have been used for the treatment of inflammatory ophthalmic diseases such as dry eye and uveoretinitis. Sideways, diverse stimuli (sensory stimulation, large intraocular pressure increases) can produce a release of ATP from ocular sensory innervation or after injury to ocular tissues. Then, ATP will activate purinergic P2 receptors present in sensory nerve endings, the iris, the ciliary body, or other tissues surrounding the anterior chamber of the eye to produce uveitis/endophthalmitis. In summary, adenosine and nucleotides can activate receptors in ocular structures susceptible to suffer from inflammatory processes. This involvement suggests the possible use of purinergic agonists and antagonists as therapeutic targets for ocular inflammation.

  8. Purinergic Receptors in Ocular Inflammation

    PubMed Central

    Guzman-Aranguez, Ana; Gasull, Xavier; Diebold, Yolanda; Pintor, Jesús

    2014-01-01

    Inflammation is a complex process that implies the interaction between cells and molecular mediators, which, when not properly “tuned,” can lead to disease. When inflammation affects the eye, it can produce severe disorders affecting the superficial and internal parts of the visual organ. The nucleoside adenosine and nucleotides including adenine mononucleotides like ADP and ATP and dinucleotides such as P1,P4-diadenosine tetraphosphate (Ap4A), and P1,P5-diadenosine pentaphosphate (Ap5A) are present in different ocular locations and therefore they may contribute/modulate inflammatory processes. Adenosine receptors, in particular A2A adenosine receptors, present anti-inflammatory action in acute and chronic retinal inflammation. Regarding the A3 receptor, selective agonists like N6-(3-iodobenzyl)-5′-N-methylcarboxamidoadenosine (CF101) have been used for the treatment of inflammatory ophthalmic diseases such as dry eye and uveoretinitis. Sideways, diverse stimuli (sensory stimulation, large intraocular pressure increases) can produce a release of ATP from ocular sensory innervation or after injury to ocular tissues. Then, ATP will activate purinergic P2 receptors present in sensory nerve endings, the iris, the ciliary body, or other tissues surrounding the anterior chamber of the eye to produce uveitis/endophthalmitis. In summary, adenosine and nucleotides can activate receptors in ocular structures susceptible to suffer from inflammatory processes. This involvement suggests the possible use of purinergic agonists and antagonists as therapeutic targets for ocular inflammation. PMID:25132732

  9. Ocular hemodynamics during isometric exercise.

    PubMed

    Kiss, B; Dallinger, S; Polak, K; Findl, O; Eichler, H G; Schmetterer, L

    2001-01-01

    The autoregulatory capacity of the human retina is well documented, but the pressure-flow relationship of the human choroid is still a matter of controversy. Recent data, using laser Doppler flowmetry to measure choroidal blood flow, indicate that the choroid has some autoregulatory potential, whereas most data using other techniques for the assessment of choroidal hemodynamics indicate that the choroidal pressure-flow curve is linear. We used a new laser interferometric technique to characterize choroidal blood flow during isometric exercise. Twenty healthy subjects performed squatting for 6 min during normocapnia and during inhalation of 5% CO2 and 95% air. Ocular fundus pulsation amplitude, flow velocities in the ophthalmic artery, intraocular pressure, and systemic hemodynamics were measured in 2-min intervals. To gain information on choroidal blood flow fundus pulsation amplitude was corrected for changes in flow pulsatility using data from the ophthalmic artery and for changes in pulse rate. Ocular perfusion pressure was calculated from mean arterial pressure and intraocular pressure. The ocular pressure-flow relationship was calculated by sorting data according to ascending ocular perfusion pressure values. In a pilot study in 6 healthy subjects comparable ocular pressure flow relationships were obtained when choroidal blood flow was assessed with the method described above and with laser Doppler flowmetry. In the main study isometric exercise caused a significant increase in mean arterial pressure (56%, P < 0.001), pulse rate (84%, P < 0.001), and intraocular pressure (37%, P 0.004), but decreased fundus pulsation amplitude (-36%, P < 0.001). Significant deviations from baseline choroidal blood flow were observed only at ocular perfusion pressures >69% during normocapnia and 70% during hypercapnia. Our data indicate that during isometric exercise the choroid has a high capacity to keep blood flow constant despite changes in perfusion pressure and that this

  10. Review of Ocular Manifestations of Nevoid Basal Cell Carcinoma Syndrome: What an Ophthalmologist Needs to Know

    PubMed Central

    Chen, Judy J.; Sartori, Juliana; Aakalu, Vinay K.; Setabutr, Pete

    2015-01-01

    Nevoid basal cell carcinoma syndrome (NBCCS) is a rare, autosomal dominant disorder characterized by multiple basal cell carcinomas (BCCs), odontogenic keratocysts, palmar and/or plantar pits, and ectopic calcifications of the falx cerebri. Myriad ophthalmologic findings are associated with NBCCS, including periocular BCCs, hypertelorism, strabismus, myelinated nerve fibers, and disorders of the retina and retinal pigment epithelium. We performed a literature search in PubMed for articles on the ophthalmologic manifestations of Gorlin syndrome, published between 1984 and 2014. Of 33 papers, 31 were included. Although Gorlin syndrome is due to mutations in a single gene, it displays variable phenotypic expressivity. Therefore, familiarity with this disorder across clinical specialties is necessary to avoid misdiagnosis. The ophthalmologist should be included in the multidisciplinary team for the management of Gorlin syndrome in order to prevent visual loss and improve the quality of life of these patients. PMID:26692711

  11. Unique and analogous functions of aquaporin O for fiber cell architecture and ocular lens transparency

    SciTech Connect

    Kumari, S.S.; Eswaramoorthy, S.; Mathias, R. T.; Varadaraj, K.

    2011-09-01

    Aquaporin (AQP) 1 and AQP0 water channels are expressed in lens epithelial and fiber cells, respectively, facilitating fluid circulation for nourishing the avascular lens to maintain transparency. Even though AQP0 water permeability is 40-fold less than AQP1, AQP0 is selectively expressed in the fibers. Delimited AQP0 fiber expression is attributed to a unique structural role as an adhesion protein. To validate this notion, we determined if wild type (WT) lens ultrastructure and fibercell adhesion are different in AQP0{sup -/-}, and TgAQP1{sup +/+}/AQP0{sup -/-} mice that transgenically express AQP1 (TgAQP1) in fibercells without AQP0 (AQP0{sup -/-}). In WT, lenses were transparent with 'Y' sutures. Fibers contained opposite end curvature, lateral interdigitations, hexagonal shape, and were arranged as concentric growth shells. AQP0{sup -/-}lenses were cataractous, lacked 'Y' sutures, ordered packing and well-defined lateral interdigitations. TgAQP1{sup +/+}/AQP0{sup -/-} lenses showed improvement in transparency and lateral interdigitations in the outer cortex while inner cortex and nuclear fibers were severely disintegrated. Transmission electron micrographs exhibited tightly packed fibercells in WT whereas AQP0{sup -/-} and TgAQP1{sup +/+}/AQP0{sup -/-}lenses had wide extracellular spaces. Fibers were easily separable by teasing in AQP0{sup -/-} and TgAQP1{sup +/+}/AQP0{sup -/-}lenses compared to WT. Our data suggest that the increased water permeability through AQP1 does not compensate for loss of AQP0 expression in TgAQP1{sup +/+}/AQP0{sup -/-} mice. Fibercell AQP0 expression is required to maintain their organization, which is a requisite for lenstransparency. AQP0 appears necessary for cell-to-cell adhesion and thereby to minimize light scattering since in the AQP0{sup -/-} and TgAQP1{sup +/+}/AQP0{sup -/-} lenses, fiber cell disorganization was evident.

  12. Development of an accommodating intra-ocular lens--in vitro prevention of re-growth of pig and rabbit lens capsule epithelial cells.

    PubMed

    van Kooten, Theo G; Koopmans, Steven; Terwee, Thom; Norrby, Sverker; Hooymans, J M M; Busscher, Henk J

    2006-11-01

    Cataract surgery is routinely performed to replace the clouded lens by a rigid polymeric intra-ocular lens unable to accommodate. By implanting a silicone gel into an intact capsular bag the accommodating properties of the natural lens can be maintained or enhanced. The implantation success of accommodating lenses is hampered by the occurrence of capsular opacification (PCO) due to lens epithelial cell (LEC) growth. In order to prevent LEC proliferation, a treatment regime using actinomycin D, cycloheximide and water was developed. The effectiveness of treatment was analyzed using an in vitro, MTT-based cell culture system and an ex vivo pig eye model in which the implanted lens-in-the-bag is cultured as a whole. LEC were exposed to treatment solutions for 5 min, then the cells were allowed to recover and to re-colonize the substratum. MTT conversion by cells was transiently inhibited by cycloheximide dissolved in water and by water alone. Exposure to actinomycin D resulted in a lasting inhibition of MTT conversion and consequently cell proliferation. These in vitro data could not be fully reproduced in the ex vivo pig eye model due to essential differences between both models. Treatment with actinomycin D containing solutions, however, resulted in a nearly complete absence of cells on the capsular wall. The pig eye model is a promising approach to further evaluate the effects of peri-surgical treatment during the accommodating intra-ocular lens implantation.

  13. Long-Term Protection of Retinal Ganglion Cells and Visual Function by Brain-Derived Neurotrophic Factor in Mice With Ocular Hypertension

    PubMed Central

    Feng, Liang; Chen, Hui; Yi, Ji; Troy, John B.; Zhang, Hao F.; Liu, Xiaorong

    2016-01-01

    Purpose Glaucoma, frequently associated with elevated intraocular pressure (IOP), is characterized by progressive retinal ganglion cell (RGC) death and vision loss. Brain-derived neurotrophic factor (BDNF) has been studied as a candidate for neuroprotection in rodent models of experimental glaucoma, yet it remains to be determined whether BDNF exerts long-term protection for subtype RGCs and vision against chronic IOP elevation. Methods We induced modest and sustained IOP elevation by laser illumination and microbead injection in mice. Using a tamoxifen-induced Cre recombinase system, BDNF was upregulated in the mouse retina when sustained IOP elevation was induced. We then examined whether overexpression of BDNF protected RGCs and vision during the period of ocular hypertension. Given that BDNF modulates axon growth and dendritic formation in a subtype-dependent manner, we tested whether BDNF protects RGC dendritic structure against the hypertensive insult also in a subtype-dependent manner. Results Sustained IOP elevation was induced and lasted up to 6 months. Overexpression of BDNF delayed progressive RGC and axon loss in hypertensive eyes. Brain-derived neurotrophic factor overexpression also helped to preserve acuity against the chronic hypertensive insult. We classified RGCs into ON and ON–OFF subtypes based on their dendritic lamination pattern in the inner plexiform layer and found that BDNF prevented ON–RGC dendritic degeneration in mice with sustained ocular hypertension. Conclusions Our data demonstrated that BDNF can protect the dendritic fields of ON RGCs and reduce RGC and vision loss in mice with sustained ocular hypertension. PMID:27421068

  14. Ocular Manifestations of Acquired Immunodeficiency Syndrome

    PubMed Central

    Kim, Young Shin; Sun, Hae Jung; Kim, Tae Hyong; Kang, Kui Dong

    2015-01-01

    Purpose To investigate the patterns and risk factors of the ocular manifestations of acquired immunodeficiency syndrome (AIDS) and their correlation with CD4+ count in the era of highly active antiretroviral therapy (HAART). Methods This retrospective study examined 127 AIDS patients who presented to Soonchunhyang University Hospital. Data were collected from patient interviews, clinical examinations, and laboratory investigations. Ophthalmologic examinations included the best-corrected visual acuity, intraocular pressure, anterior segment and adnexal examination, and dilated fundus examination. Results Of the 127 patients with AIDS, 118 were on HAART and 9 were not. The mean CD4+ count was 266.7 ± 209.1 cells/µL. There were ocular manifestations in 61 patients (48.0%). The incidence of anterior segment manifestations was higher than posterior segment manifestations at 28.3% and 19.7%, respectively. The mean CD4+ count was significantly (p < 0.05) lower in the patients with posterior versus anterior segment ocular manifestations. The most common ocular manifestation was retinal microvasculopathy (15.0%), followed by keratoconjunctivitis sicca (14.2%), conjunctival microvasculopathy (9.4%), cytomegalovirus retinitis (3.1%), herpes zoster ophthalmicus (2.4%), and blepharitis (1.6%). Retinal microvasculopathy and cytomegalovirus retinitis were common in patients with CD4+ counts <200 cells/µL, while keratoconjunctivitis sicca and conjunctival microvasculopathy were common in patients with CD4+ counts of 200 to 499 cells/µL. There was a significant (p < 0.05) association between ocular manifestation and CD4+ count or age. Conclusions The introduction of HAART has changed the landscape of ocular presentations in patients with AIDS. In this study, anterior segment and external ocular manifestations occurred more frequently than posterior segment manifestations. Also, the mean CD4+ count was significantly lower in patients with posterior segment ocular manifestations

  15. Ocular Manifestations of Acquired Immunodeficiency Syndrome.

    PubMed

    Kim, Young Shin; Sun, Hae Jung; Kim, Tae Hyong; Kang, Kui Dong; Lee, Sung Jin

    2015-08-01

    To investigate the patterns and risk factors of the ocular manifestations of acquired immunodeficiency syndrome (AIDS) and their correlation with CD4+ count in the era of highly active antiretroviral therapy (HAART). This retrospective study examined 127 AIDS patients who presented to Soonchunhyang University Hospital. Data were collected from patient interviews, clinical examinations, and laboratory investigations. Ophthalmologic examinations included the best-corrected visual acuity, intraocular pressure, anterior segment and adnexal examination, and dilated fundus examination. Of the 127 patients with AIDS, 118 were on HAART and 9 were not. The mean CD4+ count was 266.7 ± 209.1 cells/µL. There were ocular manifestations in 61 patients (48.0%). The incidence of anterior segment manifestations was higher than posterior segment manifestations at 28.3% and 19.7%, respectively. The mean CD4+ count was significantly (p < 0.05) lower in the patients with posterior versus anterior segment ocular manifestations. The most common ocular manifestation was retinal microvasculopathy (15.0%), followed by keratoconjunctivitis sicca (14.2%), conjunctival microvasculopathy (9.4%), cytomegalovirus retinitis (3.1%), herpes zoster ophthalmicus (2.4%), and blepharitis (1.6%). Retinal microvasculopathy and cytomegalovirus retinitis were common in patients with CD4+ counts <200 cells/µL, while keratoconjunctivitis sicca and conjunctival microvasculopathy were common in patients with CD4+ counts of 200 to 499 cells/µL. There was a significant (p < 0.05) association between ocular manifestation and CD4+ count or age. The introduction of HAART has changed the landscape of ocular presentations in patients with AIDS. In this study, anterior segment and external ocular manifestations occurred more frequently than posterior segment manifestations. Also, the mean CD4+ count was significantly lower in patients with posterior segment ocular manifestations versus anterior segment ocular

  16. Human natural killer cell development.

    PubMed

    Freud, Aharon G; Caligiuri, Michael A

    2006-12-01

    Our understanding of human natural killer (NK) cell development lags far behind that of human B- or T-cell development. Much of our recent knowledge of this incomplete picture comes from experimental animal models that have aided in identifying fundamental in vivo processes, including those controlling NK cell homeostasis, self-tolerance, and the generation of a diverse NK cell repertoire. However, it has been difficult to fully understand the mechanistic details of NK cell development in humans, primarily because the in vivo cellular intermediates and microenvironments of this developmental pathway have remained elusive. Although there is general consensus that NK cell development occurs primarily within the bone marrow (BM), recent data implicate secondary lymphoid tissues as principal sites of NK cell development in humans. The strongest evidence stems from the observation that the newly described stages of human NK cell development are naturally and selectively enriched within lymph nodes and tonsils compared with blood and BM. In the current review, we provide an overview of these recent findings and discuss these in the context of existing tenets in the field of lymphocyte development.

  17. Telomere Length Measurement in Different Ocular Structures: A Potential Implication in Corneal Endothelium Pathogenesis.

    PubMed

    Drigeard Desgarnier, Marie-Catherine; Zinflou, Corinne; Mallet, Justin D; Gendron, Sébastien P; Méthot, Sébastien J; Rochette, Patrick J

    2016-10-01

    Human chromosomes are protected at their end by a long portion of hexameric tandem repeats, the telomere. In somatic cells, telomere attrition caused by endogenous and exogenous oxidative stress as well as DNA replication can threaten genomic integrity and lead to the deterioration of tissue functions and an age-related physiological decline. The human eye is a complex organ in which cells of different ocular tissues are exposed to photo-oxidation, high mitochondrial metabolic activity, and/or replicative pressure. We employed a highly sensitive quantitative PCR technique to determine relative telomere length in different human ocular structures. The longest telomeres in all ocular structures analyzed are found in neural retina, and the shortest are in the cornea. Within the retina, retinal pigment epithelium has four times shorter telomeres when compared to neural retina. However, no age-dependent telomere attrition in the retina and no difference between telomere lengths in the macular region and the rest of the retina have been found. In the cornea, stroma has the longer telomeres. In the corneal endothelium, we found a clear age-dependent telomere shortening. Since the endothelium is one of the most metabolically active ocular structure, this result suggests that endogenous oxidative stress from high mitochondrial activity is a major determinant of telomere loss in this structure. Taken together, our results imply that the aging process and telomere attrition in the different ocular structures are the result of multiple factors and could not be attributed to solely exogenous or endogenous oxidation or DNA replication.

  18. The Cervico-Ocular Reflex of normal human subjects in response to transient and sinusoidal trunk rotations

    NASA Technical Reports Server (NTRS)

    Sawyer, Robert N., Jr.; Thurston, Stephen E.; Becker, Keith R.; Ackley, Charles V.; Seidman, Scott H.; Leigh, R. John

    1994-01-01

    We used the magnetic search coil technique to measure the horizontal cervico-ocular reflex (COR) of 8 subjects in response to transient or sinusoidal (0.1-1.0 Hz) trunk rotations while their heads were firmly immobilized. Although we were able to resolve eye rotations of less than 0.05 deg, the COR was hardly measurable (gain was always less than 0.07). This finding, made with the most precise measurement technique used to date, suggests that the COR makes a negligible contribution to the stability of gaze in normal subjects during natural activities.

  19. Ocular diseases: immunological and molecular mechanisms

    PubMed Central

    Song, Jing; Huang, Yi-Fei; Zhang, Wen-Jing; Chen, Xiao-Fei; Guo, Yu-Mian

    2016-01-01

    Many factors, such as environmental, microbial and endogenous stress, antigen localization, can trigger the immunological events that affect the ending of the diverse spectrum of ocular disorders. Significant advances in understanding of immunological and molecular mechanisms have been researched to improve the diagnosis and therapy for patients with ocular inflammatory diseases. Some kinds of ocular diseases are inadequately responsive to current medications; therefore, immunotherapy may be a potential choice as an alternative or adjunctive treatment, even in the prophylactic setting. This article first provides an overview of the immunological and molecular mechanisms concerning several typical and common ocular diseases; second, the functions of immunological roles in some of systemic autoimmunity will be discussed; third, we will provide a summary of the mechanisms that dictate immune cell trafficking to ocular local microenvironment in response to inflammation. PMID:27275439

  20. Ocular lesions arising after stings by hymenopteran insects.

    PubMed

    Arcieri, Enyr Saran; França, Edimar Tiago; de Oliveria, Hailton Barreiros; De Abreu Ferreira, Lizane; Ferreira, Magno Antônio; Rocha, Flávio Jaime

    2002-04-01

    To describe the ocular lesions that occur after stings from hymenopteran insects. We examined the ocular alterations in five patients who suffered ocular trauma from hymenopteran insect stings. In 4 cases where the insect was identified as a wasp, all the patients presented with persistent corneal decompensation and two presented with total cataract, requiring surgical treatment. In the case of trauma by a bee sting, the patient presented with corneal edema and an inflammatory reaction of the anterior chamber with total regression of these alterations after clinical treatment. Although a rare occurrence, ocular trauma caused by hymenopteran insects can result in severe ocular alterations in humans.

  1. Cells of human breast milk.

    PubMed

    Witkowska-Zimny, Malgorzata; Kaminska-El-Hassan, Ewa

    2017-01-01

    Human milk is a complex fluid that has developed to satisfy the nutritional requirements of infants. In addition to proteins, lipids, carbohydrates and other biologically active components, breast milk contains a diverse microbiome that is presumed to colonize the infant gastrointestinal tract and a heterogeneous population of cells with unclear physiological roles and health implications. Noteworthy cellular components of breast milk include progenitor/stem cells. This review summarizes the current state of knowledge of breast milk cells, including leukocytes, epithelial cells, stem cells and potentially probiotic bacteria.

  2. Testing ocular irritancy in vitro with the silicon microphysiometer.

    PubMed

    Bruner, L H; Miller, K R; Owicki, J C; Parce, J W; Muir, V C

    1991-01-01

    The silicon microphysiometer, an instrument based on the light-addressable potentiometric sensor, was evaluated as an in vitro alternative for assessing ocular irritancy potential. It indirectly and non-invasively measures cell metabolism by determining the rate of acid metabolite production from cells, in this case human epidermal keratinocytes, placed inside the microphysiometer chamber. The 17 materials used for the evaluation included bar soaps, a liquid hand soap, shampoos, dishwashing liquids, laundry detergents, a fabric softener and several single chemicals. All materials tested were in liquid form. The in vivo irritancy potential of the materials was obtained from historical data using the rabbit low-volume eye test. There was a positive correlation between the in vivo irritancy potential of the test materials and the concentration of test material that decreased the acidification rate of cells by 50% (MRD(50); r = 0.86, P < 0.0001). Preliminary studies suggest other endpoints obtainable from the system may also provide useful information for making ocular safety assessments. Because the method is non-invasive, it is possible to determine whether cells recover from a treatment with the test material. The metabolic rate of the cells also increases at sub-inhibitory concentrations of some of the test materials. Because of the good correlation between the in vivo and in vitro data, the ease with which test materials can be applied to the system, and the multiple endpoints available from the system, it holds great potential as a useful in vitro alternative for ocular safety testing.

  3. Interferon Regulator Factor 8 (IRF8) Limits Ocular Pathology during HSV-1 Infection by Restraining the Activation and Expansion of CD8+ T Cells

    PubMed Central

    Yu, Cheng-Rong; He, Chang; Mahdi, Rashid M.; Chan, Chi-Chao; Wang, Hongsheng; Morse, Herbert C.; Egwuagu, Charles E.

    2016-01-01

    Interferon Regulatory Factor-8 (IRF8) is constitutively expressed in monocytes and B cell lineages and plays important roles in immunity to pathogens and cancer. Although IRF8 expression is induced in activated T cells, the functional relevance of IRF8 in T cell-mediated immunity is not well understood. In this study, we used mice with targeted deletion of Irf8 in T-cells (IRF8KO) to investigate the role of IRF8 in T cell-mediated responses during herpes simplex virus 1 (HSV-1) infection of the eye. In contrast to wild type mice, HSV-1-infected IRF8KO mice mounted a more robust anti-HSV-1 immune response, which included marked expansion of HSV-1-specific CD8+ T cells, increased infiltration of inflammatory cells into the cornea and trigeminal ganglia (TG) and enhanced elimination of virus within the trigeminal ganglion. However, the consequence of the enhanced immunological response was the development of ocular inflammation, limbitis, and neutrophilic infiltration into the cornea of HSV-1-infected IRF8KO mice. Surprisingly, we observed a marked increase in virus-specific memory precursor effector cells (MPEC) in IRF8KO mice, suggesting that IRF8 might play a role in regulating the differentiation of effector CD8+ T cells to the memory phenotype. Together, our data suggest that IRF8 might play a role in restraining excess lymphocyte proliferation. Thus, modulating IRF8 levels in T cells can be exploited therapeutically to prevent immune-mediated ocular pathology during autoimmune and infectious diseases of the eye. PMID:27171004

  4. New mutations identified in the ocular albinism type 1 gene.

    PubMed

    Roma, Cristin; Ferrante, Paola; Guardiola, Ombretta; Ballabio, Andrea; Zollo, Massimo

    2007-11-01

    As the most common form of ocular albinism, ocular albinism type I (OA1) is an X-linked disorder that has an estimated prevalence of about 1:50,000. We searched for mutations through the human genome sequence draft by direct sequencing on eighteen patients with OA1, both within the coding region and in a thousand base pairs upstream of its start site. Here, we have identified eight new mutations located in the coding region of the gene. Two independent mutations, both located in the most carboxyterminal protein regions, were further characterized by immunofluorescence confocal microscopy, thus showing an impairment in their subcellular distribution into the lysosomal compartment of Cos-7A cells. The mutations found can result in protein misfolding, thus underlining the importance of the structure-function relationships of the protein as a major pathogenic mechanism in ocular albinism. Seven individuals out of eighteen (38.9%) with a clinical diagnosis of ocular albinism showed mutations, thus underlining the discrepancies between the clinical phenotype features and their genotype correlations. We postulate that mutations that have not yet been identified are potentially located in non-coding conserved regions or regulatory sequences of the OA1 gene.

  5. The association between nuclear receptors and ocular diseases.

    PubMed

    Liu, Ke; Zou, Chang; Qin, Bo

    2017-02-07

    Nuclear hormone receptors (NRs) are one of the most abundant transcription factors in the human cells. They regulate expression of genes via interactions with corresponding ligands, co-activators, and co-repressors. These molecular pathways play important roles in the development, cell differentiation, and physiologic and metabolic processes. Increasingly, targeting nuclear receptors is becoming a promising strategy for new drug development. The aim of this review is to discuss the association between nuclear receptors and eye development, and expand their role in various ocular diseases such as keratitis, cataract, glaucoma, uveitis, retinopathy, and ophthalmic tumors. Recent studies in this area are highlighted as well as future research directions and potential clinical applications. Finally, various strategies will be elucidated to inspire more targeted therapies for ocular diseases through the use of nuclear receptors.

  6. Ocular surface reconstruction update.

    PubMed

    Shimmura, Shigeto; Tsubota, Kazuo

    2002-08-01

    Ocular surface reconstruction (OSR) is now a standard procedure in the treatment of severe ocular surface disorders. The past few years have revealed the long-term results of patients who were operated on during the early stages of OSR development, and we now have a more realistic view of the benefits and limits of the procedure. On the other hand, further understanding of the physiologic role played by the amniotic membrane (AM) has opened doors to further refined techniques in treating these patients. This review will introduce some of the major contributions made during the past years in the advancement of OSR. Clinically, we are at a stage of reviewing the pros and cons of the various transplantation techniques. Identification of factors crucial for a successful OSR procedure will further improve surgical results. Basic researchers are on the verge of identifying the so-called limbal stem cells, and further understanding of AM physiology will lead the way to tissue engineering techniques as another alternative in OSR surgery.

  7. Alternative route for erythropoietin ocular administration.

    PubMed

    Resende, Ana Paula; São-Braz, Berta; Delgado, Esmeralda

    2013-08-01

    This study aimed to find an alternative route for erythropoietin (EPO) ocular administration because of its neuroprotective and neuroregenerative known properties. Ocular penetration of EPO after subconjunctival injection was assessed, and potential side-effects on the haematocrit for a 28-day period were also evaluated. Wistar Hannover female albino rats (n = 42) divided into seven groups of six were used. One group (n = 6) served as control. Six groups (n = 36) received 1,000 UI of EPO through the subconjunctival route in one of the eyes. According to the group, animals were humanely killed at 12 h (n = 6), 24 h (n = 6), 36 h (n = 6), 48 h (n = 6), and 60 h (n = 6), after EPO administration, in a total of 30 animals. Enucleation of both eyes was performed, and EPO protein distribution in the rat's retina was analyzed by immunohistochemistry. Another group of animals (n = 6) was used to collect blood samples and perform haematocrit analysis at 0, 7, 14, 21, and 28 days after unilateral EPO subconjunctival administration. The evaluation of EPO expression in the animals' retinas after subconjunctival administration yielded a strong immunostaining signal. Among the retina's layers, EPO expression was more evident in the RGC layer 24 h after the administration, and was still present on that layer till the end of the study (60 h). When administered subconjunctivally EPO reached several neuronal cells, in all retinal layers. The subconjunctival EPO administration did not cause significant changes in the haematocrit values over a 28-day period. In this study, it was demonstrated that EPO reached the retinal ganglion cell layers when administered subconjunctivally. EPO reached the retina 24 h after the subconjunctival administration, and was still present 60 h after the administration. Furthermore, it was also proved that EPO subconjunctival administration did not cause any haematopoietic significant side-effects. The subconjunctival route was shown to be a promising

  8. Ultraviolet light and ocular diseases.

    PubMed

    Yam, Jason C S; Kwok, Alvin K H

    2014-04-01

    The objective of this study is to review the association between ultraviolet (UV) light and ocular diseases. The data are sourced from the literature search of Medline up to Nov 2012, and the extracted data from original articles, review papers, and book chapters were reviewed. There is a strong evidence that ultraviolet radiation (UVR) exposure is associated with the formation of eyelid malignancies [basal cell carcinoma (BCC) and squamous cell carcinoma (SCC)], photokeratitis, climatic droplet keratopathy (CDK), pterygium, and cortical cataract. However, the evidence of the association between UV exposure and development of pinguecula, nuclear and posterior subcapsular cataract, ocular surface squamous neoplasia (OSSN), and ocular melanoma remained limited. There is insufficient evidence to determine whether age-related macular degeneration (AMD) is related to UV exposure. It is now suggested that AMD is probably related to visible radiation especially blue light, rather than UV exposure. From the results, it was concluded that eyelid malignancies (BCC and SCC), photokeratitis, CDK, pterygium, and cortical cataract are strongly associated with UVR exposure. Evidence of the association between UV exposure and development of pinguecula, nuclear and posterior subcapsular cataract, OSSN, and ocular melanoma remained limited. There is insufficient evidence to determine whether AMD is related to UV exposure. Simple behaviural changes, appropriate clothing, wearing hats, and UV blocking spectacles, sunglasses or contact lens are effective measures for UV protection.

  9. α-Aminoadipic acid protects against retinal disruption through attenuating Müller cell gliosis in a rat model of acute ocular hypertension

    PubMed Central

    Wang, Xiaolei; Su, Jier; Ding, Jingwen; Han, Song; Ma, Wei; Luo, Hong; Hughes, Guy; Meng, Zhaoyang; Yin, Yi; Wang, Yanling; Li, Junfa

    2016-01-01

    Objective Ocular hypertension is an important risk factor for glaucoma. The purpose of this study was to investigate the gliotoxic effects of α-aminoadipic acid (AAA) in a rat model of AOH and its underlying mechanisms. Materials and methods In the rat model of acute ocular hypertension (AOH), intraocular pressure was increased to 110 mmHg for 60 minutes. Animals were divided into four groups: sham operation (Ctrl), AOH, AOH + phosphate-buffered saline (PBS), and AOH + AAA. Cell apoptosis in the ganglion cell layer was detected with the terminal deoxynucleotidyl transferase-mediated uridine 5′-triphosphate-biotin nick end labeling (TUNEL) assay, and retinal ganglion cells (RGCs) immunostained with Thy-1 were counted. Müller cell activation was detected using immunostaining with glutamine synthetase and glial fibrillary acidic protein. Tumor necrosis factor-α (TNF-α) was examined using Western blot. Results In the rat model of AOH, cell apoptosis was induced in the ganglion cell layer and the number of RGCs was decreased. Müller cell gliosis in the retinas of rats was induced, and retinal protein levels of TNF-α were increased. Intravitreal treatment of AAA versus PBS control attenuated these retinal abnormalities to show protective effects in the rat model of AOH. Conclusion In the retinas of the rat model of AOH, AAA treatment attenuated retinal apoptosis in the ganglion cell layer and preserved the number of RGCs, likely through the attenuation of Müller cell gliosis and suppression of TNF-α induction. Our observations suggest that AAA might be a potential therapeutic target in glaucoma. PMID:27799744

  10. α-Aminoadipic acid protects against retinal disruption through attenuating Müller cell gliosis in a rat model of acute ocular hypertension.

    PubMed

    Wang, Xiaolei; Su, Jier; Ding, Jingwen; Han, Song; Ma, Wei; Luo, Hong; Hughes, Guy; Meng, Zhaoyang; Yin, Yi; Wang, Yanling; Li, Junfa

    2016-01-01

    Ocular hypertension is an important risk factor for glaucoma. The purpose of this study was to investigate the gliotoxic effects of α-aminoadipic acid (AAA) in a rat model of AOH and its underlying mechanisms. In the rat model of acute ocular hypertension (AOH), intraocular pressure was increased to 110 mmHg for 60 minutes. Animals were divided into four groups: sham operation (Ctrl), AOH, AOH + phosphate-buffered saline (PBS), and AOH + AAA. Cell apoptosis in the ganglion cell layer was detected with the terminal deoxynucleotidyl transferase-mediated uridine 5'-triphosphate-biotin nick end labeling (TUNEL) assay, and retinal ganglion cells (RGCs) immunostained with Thy-1 were counted. Müller cell activation was detected using immunostaining with glutamine synthetase and glial fibrillary acidic protein. Tumor necrosis factor-α (TNF-α) was examined using Western blot. In the rat model of AOH, cell apoptosis was induced in the ganglion cell layer and the number of RGCs was decreased. Müller cell gliosis in the retinas of rats was induced, and retinal protein levels of TNF-α were increased. Intravitreal treatment of AAA versus PBS control attenuated these retinal abnormalities to show protective effects in the rat model of AOH. In the retinas of the rat model of AOH, AAA treatment attenuated retinal apoptosis in the ganglion cell layer and preserved the number of RGCs, likely through the attenuation of Müller cell gliosis and suppression of TNF-α induction. Our observations suggest that AAA might be a potential therapeutic target in glaucoma.

  11. Regulatory requirements in the good manufacturing practice production of an epithelial cell graft for ocular surface reconstruction.

    PubMed

    Sheth-Shah, Radhika; Vernon, Amanda J; Seetharaman, Shankar; Neale, Michael H; Daniels, Julie T

    2016-04-01

    In the past decade, stem cell therapy has been increasingly employed for the treatment of various diseases. Subsequently, there has been a great interest in the manufacture of stem cells under good manufacturing practice, which is required by law for their use in humans. The cells for sight Stem Cell Therapy Research Unit, based at UCL Institute of Ophthalmology, delivers somatic cell-based and tissue-engineered therapies to patients suffering from blinding eye diseases at Moorfields Eye Hospital (London, UK). The following article is based on our experience in the conception, design, construction, validation and manufacturing within a good manufacturing practice manufacturing facility based in the UK. As such the regulations can be extrapolated to the 28 members stated within the EU. However, the principles may have a broad relevance outside the EU.

  12. Ultra-fast one micron spectral domain ultra-high sensitive optical micro-angiography for in vivo visualization of ocular circulation of human retina and choroid

    NASA Astrophysics Data System (ADS)

    An, Lin; Wang, Ruikang K.

    2011-03-01

    In this paper, an ultra high speed (92 kHz A-line rate) one micron spectral domain ultra high sensitive optical microangiography system was demonstrated and successfully applied on posterior part of human eye for in vivo visualizing blood perfusions of both retina and choroid. A 1 μm ASE module was utilized as the light source, which could provide much more penetration depth than conventional 800 nm system. Running at 200 frames per second, it would cost ~5 seconds for the system to finish acquiring one 3D data set, which covers ~3×3 mm2 on the retina. Applying the OMAG algorithm onto the slow axis (C-scan direction), our system can extract detailed capillary level ocular perfusion maps for different layers of both retina and choroid. The excellent agreement with the standard text book shows great potential in clinical application.

  13. Clinical Features and Treatment of Ocular Toxoplasmosis

    PubMed Central

    Park, Young-Hoon

    2013-01-01

    Ocular toxoplasmosis is a disease caused by the infection with Toxoplasma gondii through congenital or acquired routes. Once the parasite reaches the retina, it proliferates within host cells followed by rupture of the host cells and invasion into neighboring cells to make primary lesions. Sometimes the restricted parasite by the host immunity in the first scar is activated to infect another lesion nearby the scar. Blurred vision is the main complaint of ocular toxoplasmic patients and can be diagnosed by detection of antibodies or parasite DNA. Ocular toxoplasmosis needs therapy with several combinations of drugs to eliminate the parasite and accompanying inflammation; if not treated it sometimes leads to loss of vision. We describe here clinical features and currently available chemotherapy of ocular toxoplasmosis. PMID:24039281

  14. Multiple subclasses of Purkinje cells in the primate floccular complex provide similar signals to guide learning in the vestibulo-ocular reflex

    NASA Technical Reports Server (NTRS)

    Raymond, J. L.; Lisberger, S. G.

    1997-01-01

    The neural "learning rules" governing the induction of plasticity in the cerebellum were analyzed by recording the patterns of neural activity in awake, behaving animals during stimuli that induce a form of cerebellum-dependent learning. We recorded the simple- and complex-spike responses of a broad sample of Purkinje cells in the floccular complex during a number of stimulus conditions that induce motor learning in the vestibulo-ocular reflex (VOR). Each subclass of Purkinje cells carried essentially the same information about required changes in the gain of the VOR. The correlation of simple-spike activity in Purkinje cells with activity in vestibular pathways could guide learning during low-frequency but not high-frequency stimuli. Climbing fiber activity could guide learning during all stimuli tested but only if compared with the activity present approximately 100 msec earlier in either vestibular pathways or Purkinje cells.

  15. Multiple subclasses of Purkinje cells in the primate floccular complex provide similar signals to guide learning in the vestibulo-ocular reflex

    NASA Technical Reports Server (NTRS)

    Raymond, J. L.; Lisberger, S. G.

    1997-01-01

    The neural "learning rules" governing the induction of plasticity in the cerebellum were analyzed by recording the patterns of neural activity in awake, behaving animals during stimuli that induce a form of cerebellum-dependent learning. We recorded the simple- and complex-spike responses of a broad sample of Purkinje cells in the floccular complex during a number of stimulus conditions that induce motor learning in the vestibulo-ocular reflex (VOR). Each subclass of Purkinje cells carried essentially the same information about required changes in the gain of the VOR. The correlation of simple-spike activity in Purkinje cells with activity in vestibular pathways could guide learning during low-frequency but not high-frequency stimuli. Climbing fiber activity could guide learning during all stimuli tested but only if compared with the activity present approximately 100 msec earlier in either vestibular pathways or Purkinje cells.

  16. Ocular Screening System

    NASA Technical Reports Server (NTRS)

    1987-01-01

    Used to detect eye problems in children through analysis of retinal reflexes, the system incorporates image processing techniques. VISISCREEN's photorefractor is basically a 35 millimeter camera with a telephoto lens and an electronic flash. By making a color photograph, the system can test the human eye for refractive error and obstruction in the cornea or lens. Ocular alignment problems are detected by imaging both eyes simultaneously. Electronic flash sends light into the eyes and the light is reflected from the retina back to the camera lens. Photorefractor analyzes the retinal reflexes generated by the subject's response to the flash and produces an image of the subject's eyes in which the pupils are variously colored. The nature of a defect, where such exists, is identifiable by atrained observer's visual examination.

  17. Photorefractor ocular screening system

    NASA Technical Reports Server (NTRS)

    Richardson, John R. (Inventor); Kerr, Joseph H. (Inventor)

    1987-01-01

    A method and apparatus for detecting human eye defects, particularly detection of refractive error is presented. Eye reflex is recorded on color film when the eyes are exposed to a flash of light. The photographs are compared with predetermined standards to detect eye defects. The base structure of the ocular screening system is a folding interconnect structure, comprising hinged sections. Attached to one end of the structure is a head positioning station which comprises vertical support, a head positioning bracket having one end attached to the top of the support, and two head positioning lamps to verify precise head positioning. At the opposite end of the interconnect structure is a camera station with camera, electronic flash unit, and blinking fixation lamp, for photographing the eyes of persons being evaluated.

  18. The Role of Infectious Agents in the Etiology of Ocular Adnexal Neoplasia

    PubMed Central

    Verma, Varun; Shen, Defen; Sieving, Pamela C.; Chan, Chi-Chao

    2008-01-01

    Given the fact that infectious agents contribute to around 18% of human cancers worldwide, it would seem prudent to explore their role in neoplasms of the ocular adnexa: primary malignancies of the conjunctiva, lacrimal glands, eyelids, and orbit. By elucidating the mechanisms by which infectious agents contribute to oncogenesis, the management, treatment, and prevention of these neoplasms may one day parallel what is already in place for cancers such as cervical cancer, hepatocellular carcinoma, gastric mucosa-associated lymphoid tissue lymphoma and gastric adenocarcinoma. Antibiotic treatment and vaccines against infectious agents may herald a future with a curtailed role for traditional therapies of surgery, radiation, and chemotherapy. Unlike other malignancies for which large epidemiological studies are available, analyzing ocular adnexal neoplasms is challenging as they are relatively rare. Additionally, putative infectious agents seemingly display an immense geographic variation that has led to much debate regarding the relative importance of one organism versus another. This review discusses the pathogenetic role of several microorganisms in different ocular adnexal malignancies, including human papilloma virus in conjunctival papilloma and squamous cell carcinoma, human immunodeficiency virus in conjunctival squamous carcinoma, Kaposi sarcoma-associated herpes virus or human herpes simplex virus-8 (KSHV/HHV-8) in conjunctival Kaposi sarcoma, Helicobacter pylori (H. pylori,), Chlamydia, and hepatitis C virus in ocular adnexal mucosa-associated lymphoid tissue lymphomas. Unlike cervical cancer where a single infectious agent, human papilloma virus, is found in greater than 99% of lesions, multiple organisms may play a role in the etiology of certain ocular adnexal neoplasms by acting through similar mechanisms of oncogenesis, including chronic antigenic stimulation and the action of infectious oncogenes. However, similar to other human malignancies

  19. Roles of IL-6 in Ocular Inflammation: A Review.

    PubMed

    Ghasemi, Hassan

    2017-02-01

    This review represents the current in vitro, in vivo animal and human researches on the roles of IL-6 in inflammatory ocular disorders. Data sources were literature reviewed using PubMed, Medline, and ISI Databases (since 1981 to late 2016). Search items included interleukine-6 (IL-6); chemokine; cytokine, alone or in combination with serum, aqueous, vitreous, eye, ocular, ophthalmic, and review. IL-6 is found to be involved in ocular inflammation. Ocular effects of IL-6 differ based on the source of the secretion and site of the action. The most important effects of IL-6 in the eyes are angiogenic activities and induction of ocular inflammation. IL-6 plays an important role in ocular inflammation and angiogenesis in conjunctiva, cornea, iris, retina, and orbit. Anti-IL-6 targeted immunotherapy has recently been employed as an important treatment modality in IL-6-related ocular disorders, provided that IL-6 signal blocking takes place in preferred and favorite targets.

  20. Comparison of in vivo efficacy of different ocular lubricants in dry eye animal models.

    PubMed

    Zheng, Xiaodong; Goto, Tomoko; Ohashi, Yuichi

    2014-04-29

    To compare the efficacy of three types of ocular lubricants in protecting corneal epithelial cells in dry eye animal models. Ocular lubricants containing 0.1% or 0.3% sodium hyaluronate (SH), carboxymethylcellulose (CMC), or hydroxypropyl methylcellulose (HPMC) were tested. First, ocular lubricant containing 0.002% fluorescein was dropped onto the rabbit corneas. The fluorescein intensity as an index of retention was measured. Second, a rabbit dry eye model was made by holding the eye open with a speculum, and 50 μL of each ocular lubricant was dropped onto the cornea. After 3 hours, the corneas were stained with 1% methylene blue (MB), and the absorbance of MB was measured. Third, a rat dry eye model was treated with the ocular lubricants for 4 weeks, and the corneal fluorescein staining was scored. Eyes treated with physiological saline were used as controls. Finally, immunohistochemistry was used to analyze occludin, an epithelial barrier protein, in cultured human corneal epithelial cells pretreated with ocular lubricants and desiccated for 20 or 60 minutes. Our results showed that 0.3% SH had a significantly longer retention time than the other lubricants (all P < 0.01). The absorbance of MB was significantly lower in the 0.3% SH group. The corneas of rats exposed to 0.3% SH had significantly lower fluorescein staining scores. A significantly higher number of occludin-positive cells were found after exposure to 0.3% SH than other lubricants. Ocular lubricant containing 0.3% SH would be preferable to treat patients with dry eye syndrome. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

  1. Perspectives on human stem cell research.

    PubMed

    Jung, Kyu Won

    2009-09-01

    Human stem cell research draws not only scientists' but the public's attention. Human stem cell research is considered to be able to identify the mechanism of human development and change the paradigm of medical practices. However, there are heated ethical and legal debates about human stem cell research. The core issue is that of human dignity and human life. Some prefer human adult stem cell research or iPS cell research, others hES cell research. We do not need to exclude any type of stem cell research because each has its own merits and issues, and they can facilitate the scientific revolution when working together.

  2. Ocular disease and driving.

    PubMed

    Wood, Joanne M; Black, Alex A

    2016-09-01

    As the driving population ages, the number of drivers with visual impairment resulting from ocular disease will increase given the age-related prevalence of ocular disease. The increase in visual impairment in the driving population has a number of implications for driving outcomes. This review summarises current research regarding the impact of common ocular diseases on driving ability and safety, with particular focus on cataract, glaucoma, age-related macular degeneration, hemianopia and diabetic retinopathy. The evidence considered includes self-reported driving outcomes, driving performance (on-road and simulator-based) and various motor vehicle crash indices. Collectively, this review demonstrates that driving ability and safety are negatively affected by ocular disease; however, further research is needed in this area. Older drivers with ocular disease need to be aware of the negative consequences of their ocular condition and in the case where treatment options are available, encouraged to seek these earlier for optimum driving safety and quality of life benefits.

  3. Ocular Surface Squamous Neoplasia in 200 Patients: A Case-Control Study of Immunosuppression Resulting from Human Immunodeficiency Virus versus Immunocompetency.

    PubMed

    Kamal, Saurabh; Kaliki, Swathi; Mishra, Dilip K; Batra, Jyoti; Naik, Milind N

    2015-08-01

    To describe and compare the clinical presentation, treatment outcomes, and histopathologic features of ocular surface squamous neoplasia (OSSN) based on human immunodeficiency virus (HIV) status. Case-control study. A total of 200 patients with OSSN, of whom 83 (41%) had positive results for HIV and were classified as cases and 117 (59%) had negative results for HIV and were classified as controls. Enzyme-linked immunosorbent assay for HIV, conjuntival excision biopsy, extended enucleation, orbital exenteration. Clinical features, treatment outcomes, and histopathologic characteristics. The mean age at presentation of OSSN in both cases and controls was 40 years (median, 40 years; range, 13-65 years) and in controls was 40 years (median, 38 years; range, 15-80 years). On comparison of cases versus controls with OSSN, HIV-positive individuals had larger (12 vs. 8 mm; P < 0.001) and thicker (3.2 vs. 2.3 mm; P = 0.041) tumors, with a higher incidence of corneal (60% vs. 40%; P = 0.007), scleral (19% vs. 9%; P = 0.044), and orbital (13% vs. 3%; P = 0.019) invasion and a higher need for extended enucleation or exenteration (27% vs. 11%; P < 0.001). The bilateral presentation (11% vs. 4%; P = 0.13), need for lamellar sclerectomy (13% vs. 8%; P = 0.29), and tumor recurrence after primary treatment (30% vs. 20%; P = 0.12) was higher in HIV-positive cases compared with HIV-negative controls. However, these features were not statistically significant. Based on American Joint Committee on Cancer classification, T1 tumor was more common in controls (13% in cases vs. 35% in controls; P = 0.0009), and T4 tumor was more common in cases (13% in cases vs. 4% in controls; P = 0.019). None of the patients demonstrated systemic metastases or died of disease during a mean follow-up period of 10 months (median, 4 months; range, <1-75 months) in cases and 9 months (median, 4 months; range, <1-99 months) in controls. Ocular surface squamous neoplasia in HIV-positive individuals is

  4. Diffusion inside living human cells

    NASA Astrophysics Data System (ADS)

    Leijnse, N.; Jeon, J.-H.; Loft, S.; Metzler, R.; Oddershede, L. B.

    2012-04-01

    Naturally occurring lipid granules diffuse in the cytoplasm and can be used as tracers to map out the viscoelastic landscape inside living cells. Using optical trapping and single particle tracking we found that lipid granules exhibit anomalous diffusion inside human umbilical vein endothelial cells. For these cells the exact diffusional pattern of a particular granule depends on the physiological state of the cell and on the localization of the granule within the cytoplasm. Granules located close to the actin rich periphery of the cell move less than those located towards to the center of the cell or within the nucleus. Also, granules in cells which are stressed by intense laser illumination or which have attached to a surface for a long period of time move in a more restricted fashion than those within healthy cells. For granules diffusing in healthy cells, in regions away from the cell periphery, occurrences of weak ergodicity breaking are observed, similar to the recent observations inside living fission yeast cells [1].

  5. In vitro ultraviolet–induced damage in human corneal, lens, and retinal pigment epithelial cells

    PubMed Central

    Youn, Hyun-Yi; Sivak, Jacob G.; Jones, Lyndon W.

    2011-01-01

    Purpose The purpose was to develop suitable in vitro methods to detect ocular epithelial cell damage when exposed to UV radiation, in an effort to evaluate UV-absorbing ophthalmic biomaterials. Methods Human corneal epithelial cells (HCEC), lens epithelial cells (HLEC), and retinal pigment epithelial cells (ARPE-19) were cultured and Ultraviolet A/Ultraviolet B (UVA/UVB) blocking filters and UVB-only blocking filters were placed between the cells and a UV light source. Cells were irradiated with UV radiations at various energy levels with and without filter protections. Cell viability after exposure was determined using the metabolic dye alamarBlue and by evaluating for changes in the nuclei, mitochondria, membrane permeability, and cell membranes of the cells using the fluorescent dyes Hoechst 33342, rhodamine 123, calcein AM, ethidium homodimer-1, and annexin V. High-resolution images of the cells were taken with a Zeiss 510 confocal laser scanning microscope. Results The alamarBlue assay results of UV-exposed cells without filters showed energy level-dependent decreases in cellular viability. However, UV treated cells with 400 nm LP filter protection showed the equivalent viability to untreated control cells at all energy levels. Also, UV irradiated cells with 320 nm LP filter showed lower cell viability than the unexposed control cells, yet higher viability than UV-exposed cells without filters in an energy level-dependent manner. The confocal microscopy results also showed that UV radiation can cause significant dose-dependent degradations of nuclei and mitochondria in ocular cells. The annexin V staining also showed an increased number of apoptotic cells after UV irradiation. Conclusions The findings suggest that UV-induced HCEC, HLEC, and ARPE-19 cell damage can be evaluated by bioassays that measure changes in the cell nuclei, mitochondria, cell membranes, and cell metabolism, and these assay methods provide a valuable in vitro model for evaluating the

  6. Three-dimensional model of angiogenesis: coculture of human retinal cells with bovine aortic endothelial cells in the NASA bioreactor.

    PubMed

    Dutt, Kamla; Sanford, Gary; Harris-Hooker, Sandra; Brako, Lawrence; Kumar, Ravindra; Sroufe, Angela; Melhado, Caroline

    2003-10-01

    Ocular angiogenesis is the leading cause of blindness and is associated with diabetic retinopathy and age-related macular degeneration. We describe, in this report, our preliminary studies using a horizontally rotating bioreactor (HRB), developed by the National Aeronautics and Space Administration (NASA), to explore growth and differentiation-associated events in the early phase of ocular angiogenesis. Human retinal (HRet) cells and bovine endothelial cells (ECs) were cocultured on laminin-coated Cytodex-3 microcarrier beads in an HRB for 1-36 days. Endothelial cells grown alone in the HRB remained cuboidal and were well differentiated. However, when HRet cells were cocultured with ECs, cordlike structures formed as early as 18-36 h and were positive for von Willebrand factor. In addition to the formation of cords and capillary-like structures, ECs showed the beginning of sprouts. The HRB seems not only to promote accelerated capillary formation, but also to enhance differentiation of retinal precursor cells. This leads to the formation of rosette-like structures (which may be aggregates of photoreceptors that were positive for rhodopsin). Upregulation of vascular endothelial growth factor and basic fibroblast growth factor was seen in retinal cells grown in the HRB as compared with monolayers and could be one of the factors responsible for accelerated capillary formation. Hence, the HRB promotes three-dimensional assembly and differentiation, possibly through promoting cell-to-cell interaction and/or secretion of growth and differentiation factors.

  7. Phenotypic and Functional Characterization of Herpes Simplex Virus Glycoprotein B Epitope-Specific Effector and Memory CD8+ T Cells from Symptomatic and Asymptomatic Individuals with Ocular Herpes

    PubMed Central

    Khan, Arif A.; Srivastava, Ruchi; Spencer, Doran; Garg, Sumit; Fremgen, Daniel; Vahed, Hawa; Lopes, Patricia P.; Pham, Thanh T.; Hewett, Charlie; Kuang, Jasmine; Ong, Nicolas; Huang, Lei; Scarfone, Vanessa M.; Nesburn, Anthony B.

    2015-01-01

    ABSTRACT Herpes simplex virus 1 (HSV-1) glycoprotein B (gB)-specific CD8+ T cells protect mice from herpes infection and disease. However, whether and which HSV-1 gB-specific CD8+ T cells play a key role in the “natural” protection seen in HSV-1-seropositive healthy asymptomatic (ASYMP) individuals (who have never had clinical herpes disease) remain to be determined. In this study, we have dissected the phenotypes and the functions of HSV-1 gB-specific CD8+ T cells from HLA-A*02:01 positive, HSV-1 seropositive ASYMP and symptomatic (SYMP) individuals (with a history of numerous episodes of recurrent ocular herpes disease). We found the following. (i) Healthy ASYMP individuals maintained a significantly higher proportion of differentiated HSV-1 gB-specific effector memory CD8+ T cells (TEM cells) (CD45RAlow CCR7low CD44high CD62Llow). In contrast, SYMP patients had frequent less-differentiated central memory CD8+ T cells (TCM cells) (CD45RAlow CCR7high CD44low CD62Lhigh). (ii) ASYMP individuals had significantly higher proportions of multifunctional effector CD8+ T cells which responded mainly to gB342–350 and gB561–569 “ASYMP” epitopes, and simultaneously produced IFN-γ, CD107a/b, granzyme B, and perforin. In contrast, effector CD8+ T cells from SYMP individuals were mostly monofunctional and were directed mainly against nonoverlapping gB17–25 and gB183–191 “SYMP” epitopes. (iii) Immunization of an HLA-A*02:01 transgenic mouse model of ocular herpes with “ASYMP” CD8+ TEM cell epitopes, but not with “SYMP” CD8+ TCM cell epitopes, induced a strong CD8+ T cell-dependent protective immunity against ocular herpes infection and disease. Our findings provide insights into the role of HSV-specific CD8+ TEM cells in protection against herpes and should be considered in the development of an effective vaccine. IMPORTANCE A significantly higher proportion of differentiated and multifunctional HSV-1 gB-specific effector memory CD8+ T cells (TEM

  8. Phenotypic and functional characterization of herpes simplex virus glycoprotein B epitope-specific effector and memory CD8+ T cells from symptomatic and asymptomatic individuals with ocular herpes.

    PubMed

    Khan, Arif A; Srivastava, Ruchi; Spencer, Doran; Garg, Sumit; Fremgen, Daniel; Vahed, Hawa; Lopes, Patricia P; Pham, Thanh T; Hewett, Charlie; Kuang, Jasmine; Ong, Nicolas; Huang, Lei; Scarfone, Vanessa M; Nesburn, Anthony B; Wechsler, Steven L; BenMohamed, Lbachir

    2015-04-01

    Herpes simplex virus 1 (HSV-1) glycoprotein B (gB)-specific CD8(+) T cells protect mice from herpes infection and disease. However, whether and which HSV-1 gB-specific CD8(+) T cells play a key role in the "natural" protection seen in HSV-1-seropositive healthy asymptomatic (ASYMP) individuals (who have never had clinical herpes disease) remain to be determined. In this study, we have dissected the phenotypes and the functions of HSV-1 gB-specific CD8(+) T cells from HLA-A*02:01 positive, HSV-1 seropositive ASYMP and symptomatic (SYMP) individuals (with a history of numerous episodes of recurrent ocular herpes disease). We found the following. (i) Healthy ASYMP individuals maintained a significantly higher proportion of differentiated HSV-1 gB-specific effector memory CD8(+) T cells (TEM cells) (CD45RA(low) CCR7(low) CD44(high) CD62L(low)). In contrast, SYMP patients had frequent less-differentiated central memory CD8(+) T cells (TCM cells) (CD45RA(low) CCR7(high) CD44(low) CD62L(high)). (ii) ASYMP individuals had significantly higher proportions of multifunctional effector CD8(+) T cells which responded mainly to gB342-350 and gB561-569 "ASYMP" epitopes, and simultaneously produced IFN-γ, CD107(a/b), granzyme B, and perforin. In contrast, effector CD8(+) T cells from SYMP individuals were mostly monofunctional and were directed mainly against nonoverlapping gB17-25 and gB183-191 "SYMP" epitopes. (iii) Immunization of an HLA-A*02:01 transgenic mouse model of ocular herpes with "ASYMP" CD8(+) TEM cell epitopes, but not with "SYMP" CD8(+) TCM cell epitopes, induced a strong CD8(+) T cell-dependent protective immunity against ocular herpes infection and disease. Our findings provide insights into the role of HSV-specific CD8(+) TEM cells in protection against herpes and should be considered in the development of an effective vaccine. A significantly higher proportion of differentiated and multifunctional HSV-1 gB-specific effector memory CD8(+) T cells (TEM cells

  9. Prediction of Ocular Drug Distribution from Systemic Blood Circulation.

    PubMed

    Vellonen, Kati-Sisko; Soini, Esa-Matti; Del Amo, Eva M; Urtti, Arto

    2016-09-06

    Systemically circulating drugs may distribute to ocular tissues across the blood-ocular barriers. Ocular distribution is utilized in the treatment of ocular diseases with systemic medications, but ocular delivery of systemic drugs and xenobiotics may also lead to adverse ocular effects. Ocular distribution after systemic drug administration has not been predicted or modeled. In this study, distribution clearance between vitreous and plasma was obtained from a previous QSPR model for clearance of intravitreal drugs. These values were used in a pharmacokinetic simulation model to describe entry of unbound drug from plasma to vitreous. The simulation models predicted ocular distribution of 10 systemic drugs in rabbit eyes within 1.96 mean fold error and the distribution of cefepime from plasma to vitreous in humans. This is the first attempt to predict ocular distribution of systemic drugs. Reliable predictions were obtained using systemic concentrations of unbound drug, computational value of ocular distribution clearance, and a simple pharmacokinetic model. This approach can be used in drug discovery to estimate ocular drug exposure at an early stage.

  10. Thermography in ocular inflammation

    PubMed Central

    Kawali, Ankush A

    2013-01-01

    Background and Objectives: The purpose of this study was to evaluate ocular inflammatory and non-inflammatory conditions using commercially available thermal camera. Materials and Methods: A non-contact thermographic camera (FLIR P 620) was used to take thermal pictures of seven cases of ocular inflammation, two cases of non-inflammatory ocular pathology, and one healthy subject with mild refractive error only. Ocular inflammatory cases included five cases of scleritis, one case of postoperative anterior uveitis, and a case of meibomian gland dysfunction with keratitis (MGD-keratitis). Non-inflammatory conditions included a case of conjunctival benign reactive lymphoid hyperplasia (BRLH) and a case of central serous chorio-retinopathy. Thermal and non-thermal photographs were taken, and using analyzing software, the ocular surface temperature was calculated. Results: Patient with fresh episode of scleritis revealed high temperature. Eyes with MGD-keratitis depicted lower temperature in clinically more affected eye. Conjunctival BRLH showed a cold lesion on thermography at the site of involvement, in contrast to cases of scleritis with similar clinical presentation. Conclusion: Ocular thermal imaging is an underutilized diagnostic tool which can be used to distinguish inflammatory ocular conditions from non-inflammatory conditions. It can also be utilized in the evaluation of tear film in dry eye syndrome. Its applications should be further explored in uveitis and other ocular disorders. Dedicated “ocular thermographic” camera is today's need of the hour. PMID:24347863

  11. Cluster bomb ocular injuries.

    PubMed

    Mansour, Ahmad M; Hamade, Haya; Ghaddar, Ayman; Mokadem, Ahmad Samih; El Hajj Ali, Mohamad; Awwad, Shady

    2012-01-01

    To present the visual outcomes and ocular sequelae of victims of cluster bombs. This retrospective, multicenter case series of ocular injury due to cluster bombs was conducted for 3 years after the war in South Lebanon (July 2006). Data were gathered from the reports to the Information Management System for Mine Action. There were 308 victims of clusters bombs; 36 individuals were killed, of which 2 received ocular lacerations and; 272 individuals were injured with 18 receiving ocular injury. These 18 surviving individuals were assessed by the authors. Ocular injury occurred in 6.5% (20/308) of cluster bomb victims. Trauma to multiple organs occurred in 12 of 18 cases (67%) with ocular injury. Ocular findings included corneal or scleral lacerations (16 eyes), corneal foreign bodies (9 eyes), corneal decompensation (2 eyes), ruptured cataract (6 eyes), and intravitreal foreign bodies (10 eyes). The corneas of one patient had extreme attenuation of the endothelium. Ocular injury occurred in 6.5% of cluster bomb victims and 67% of the patients with ocular injury sustained trauma to multiple organs. Visual morbidity in civilians is an additional reason for a global ban on the use of cluster bombs.

  12. Cluster Bomb Ocular Injuries

    PubMed Central

    Mansour, Ahmad M.; Hamade, Haya; Ghaddar, Ayman; Mokadem, Ahmad Samih; El Hajj Ali, Mohamad; Awwad, Shady

    2012-01-01

    Purpose: To present the visual outcomes and ocular sequelae of victims of cluster bombs. Materials and Methods: This retrospective, multicenter case series of ocular injury due to cluster bombs was conducted for 3 years after the war in South Lebanon (July 2006). Data were gathered from the reports to the Information Management System for Mine Action. Results: There were 308 victims of clusters bombs; 36 individuals were killed, of which 2 received ocular lacerations and; 272 individuals were injured with 18 receiving ocular injury. These 18 surviving individuals were assessed by the authors. Ocular injury occurred in 6.5% (20/308) of cluster bomb victims. Trauma to multiple organs occurred in 12 of 18 cases (67%) with ocular injury. Ocular findings included corneal or scleral lacerations (16 eyes), corneal foreign bodies (9 eyes), corneal decompensation (2 eyes), ruptured cataract (6 eyes), and intravitreal foreign bodies (10 eyes). The corneas of one patient had extreme attenuation of the endothelium. Conclusions: Ocular injury occurred in 6.5% of cluster bomb victims and 67% of the patients with ocular injury sustained trauma to multiple organs. Visual morbidity in civilians is an additional reason for a global ban on the use of cluster bombs. PMID:22346132

  13. Emerging therapeutics for ocular surface disease.

    PubMed

    Bielory, Brett P; Shah, Steven P; O'Brien, Terrence P; Perez, Victor L; Bielory, Leonard

    2016-10-01

    The present review provides an overview on the potential of different systemic and topical treatments in chronic forms of ocular allergy and dry eye disorder (DED). The impact on anterior surface of ocular inflammatory disorder encompasses an array of conditions, which are frequently underreported. This can contribute to underdiagnoses and ineffective management from healthcare providers such as an allergist and/or ophthalmologist who routinely provide care for these common disorders. Owing to the current limited therapeutic options, healthcare providers are routinely seeking alternative treatments that could facilitate effective management of the conditions. Recent advances in immunopathophysiology of ocular surface disorders has provided new potential targets and therapeutic strategies for the treatment of DED and ocular allergy that may include various immunobiological modulators. These modulators have focused on regulating the Th1 and Th2 immune-mediated inflammatory pathways that inhibit various cytokines (e.g. IL-1, IL-4, IL-5, IL-9, IL-13) antibodies (e.g. IgE), and other surface markers of various cell lines (e.g. activated T-lymphocytes, lymphocyte function-associated antigen-1). Recent findings about the pathophysiology of DED and ocular allergy have led to the greater understanding of the molecular and cellular mechanisms of ocular surface diseases leading to the potential novel targets for immunomodulation of anterior surface ocular disorders. New topical glucocorticoids, leukotriene receptor antagonists, IL-1 antagonists, IL-5, IL-4/IL-13 antagonists, integrin antagonists, and quinolone derivatives appear to be encouraging.

  14. Goblet cells of the normal human bulbar conjunctiva and their assessment by impression cytology sampling.

    PubMed

    Doughty, Michael J

    2012-07-01

    Goblet cells of the conjunctiva are the main source of mucus for the ocular surface. The objectives of this review are to consider the goblet cells as assessed by various histological, cytological and electron microscopy methods, and to assess the consistency of published reports (over more than 25 years) of goblet cell density (GCD) from impression cytology specimens from nominally healthy human subjects. Reported GCD values have been notably variable, with a range from 24 to 2226 cells/mm² for average values. Data analysis suggests that a high density of goblet cells should be expected for the healthy human conjunctiva, with a tendency toward higher values in samples taken from normally covered locations (inferior and superior bulbar conjunctiva) of the open eye (at 973 +/- 789 cells/ mm²) than in samples taken from exposed (interpalpebral) locations (at 427 +/- 376 cells/mm²). No obvious change in GCD was found with respect to age, perhaps because the variability of the data did not allow detection of any age-related decline in GCD. Analyses of published data from 33 other sources indicated a trend for GCD to be lower than normal across a spectrum of ocular surface diseases.

  15. Ocular Dirofilariasis, a Case Report

    PubMed Central

    Tafti, MR Fallah; Hajilary, A; Siatiri, H; Rokni, MB; Mobedi, I; Mowlavi, Gh

    2010-01-01

    Accidental infection with animal filarial worms in humans is a dilemma for clinicians and parasitologists throughout the world. To date a variety of such rare parasitoses have been reported mostly in tropics and subtropics. Human dirofilariasis is among those unusual zoonotic infections that occasionally have been observed in the eye and in subcutaneous areas exhibiting with nodule formation. Filarial worms are transmitted to humans through invertebrate biological vectors such as certain species of mosquitoes. The present report describes a peculiar case of ocular dirofilariasis in a 49-year-old man resident in Iran. PMID:22347257

  16. Human Ocular Counter-Rolling and Roll Tilt Perception during Off-Vertical Axis Rotation after Spaceflight

    NASA Technical Reports Server (NTRS)

    Clement, Gilles; Denise, Pierre; Reschke, Millard; Wood, Scott J.

    2007-01-01

    Ocular counter-rolling (OCR) induced by whole body tilt in roll has been explored after spaceflight as an indicator of the adaptation of the otolith function to microgravity. It has been claimed that the overall pattern of OCR responses during static body tilt after spaceflight is indicative of a decreased role of the otolith function, but the results of these studies have not been consistent, mostly due to large variations in the OCR within and across individuals. By contrast with static head tilt, off-vertical axis rotation (OVAR) presents the advantage of generating a sinusoidal modulation of OCR, allowing averaged measurements over several cycles, thus improving measurement accuracy. Accordingly, OCR and the sense of roll tilt were evaluated in seven astronauts before and after spaceflight during OVAR at 45 /s in darkness at two angles of tilt (10 and 20 ). There was no significant difference in OCR during OVAR immediately after landing compared to preflight. However, the amplitude of the perceived roll tilt during OVAR was significantly larger immediately postflight, and then returned to control values in the following days. Since the OCR response is predominantly attributed to the shearing force exerted on the utricular macula, the absence of change in OCR postflight suggests that the peripheral otolith organs function normally after short-term spaceflight. However, the increased sense of roll tilt indicates an adaptation in the central processing of gravitational input, presumably related to a re-weigthing of the internal representation of gravitational vertical as a result of adaptation to microgravity.

  17. Human Ocular Counter-Rolling and Roll Tilt Perception during Off-Vertical Axis Rotation after Spaceflight

    NASA Technical Reports Server (NTRS)

    Clement, Gilles; Denise, Pierre; Reschke, Millard; Wood, Scott J.

    2007-01-01

    Ocular counter-rolling (OCR) induced by whole body tilt in roll has been explored after spaceflight as an indicator of the adaptation of the otolith function to microgravity. It has been claimed that the overall pattern of OCR responses during static body tilt after spaceflight is indicative of a decreased role of the otolith function, but the results of these studies have not been consistent, mostly due to large variations in the OCR within and across individuals. By contrast with static head tilt, off-vertical axis rotation (OVAR) presents the advantage of generating a sinusoidal modulation of OCR, allowing averaged measurements over several cycles, thus improving measurement accuracy. Accordingly, OCR and the sense of roll tilt were evaluated in seven astronauts before and after spaceflight during OVAR at 45 /s in darkness at two angles of tilt (10 and 20 ). There was no significant difference in OCR during OVAR immediately after landing compared to preflight. However, the amplitude of the perceived roll tilt during OVAR was significantly larger immediately postflight, and then returned to control values in the following days. Since the OCR response is predominantly attributed to the shearing force exerted on the utricular macula, the absence of change in OCR postflight suggests that the peripheral otolith organs function normally after short-term spaceflight. However, the increased sense of roll tilt indicates an adaptation in the central processing of gravitational input, presumably related to a re-weigthing of the internal representation of gravitational vertical as a result of adaptation to microgravity.

  18. Dose-Response Functions for the Olfactory, Nasal Trigeminal, and Ocular Trigeminal Detectability of Airborne Chemicals by Humans.

    PubMed

    Cometto-Muñiz, J Enrique; Abraham, Michael H

    2016-01-01

    We gathered from the literature 47 odor and 37 trigeminal (nasal and ocular) chemesthetic psychometric (i.e., detectability or dose-response) functions from a group of 41 chemicals. Vapors delivered were quantified by analytical methods. All functions were very well fitted by the sigmoid (logistic) equation: y = 1 / (1 + e({-(x-C)/D})), where parameter C quantifies the detection threshold concentration and parameter D the steepness of the function. Odor and chemesthetic functions showed no concentration overlap: olfactory functions grew along the parts per billion (ppb by volume) range or lower, whereas trigeminal functions grew along the part per million (ppm by volume) range. Although, on average, odor detectability rose from chance detection to perfect detection within 2 orders of magnitude in concentration, chemesthetic detectability did it within one. For 16 compounds having at least 1 odor and 1 chemesthetic function, the average gap between the 2 functions was 4.6 orders of magnitude in concentration. A quantitative structure-activity relationship (QSAR) using 5 chemical descriptors that had previously described stand-alone odor and chemesthetic threshold values, also holds promise to describe, and eventually predict, olfactory and chemesthetic detectability functions, albeit functions from additional compounds are needed to strengthen the QSAR.

  19. Ocular effects of radiofrequency energy.

    PubMed

    Elder, J A

    2003-01-01

    Radiofrequency (RF) energy has been reported to cause a variety of ocular effects, primarily cataracts but also effects on the retina, cornea, and other ocular systems. Cataracts have been observed in experimental animals when one eye was exposed to a localized, very high RF field and the other eye was the unexposed control. The results show that 2450 MHz exposures for >or=30 min at power densities causing extremely high dose rates (>or=150 W/kg) and temperatures (>or=41 degrees C) in or near the lens caused cataracts in the rabbit eye. However, cataracts were not observed in the monkey eye exposed to similar exposure conditions, reflecting the different patterns of energy absorption (SAR, specific absorption rate) distribution, due to their different facial structure. Since the monkey head is similar in structure to the human head, the nonhuman primate study showed that the incident power density levels causing cataracts in rabbits and other laboratory animals cannot be directly extrapolated to primates, including human beings. It is reasonable to assume that an SAR that would induce temperatures >or=41 degrees C in or near the lens in the human eye would produce cataracts by the same mechanism (heating) that caused cataracts in the rabbit lens; however, such an exposure would greatly exceed the currently allowable limits for human exposure and would be expected to cause unacceptable effects in other parts of the eye and face. Other ocular effects including corneal lesions, retinal effects, and changes in vascular permeability, have been observed after localized exposure of the eye of laboratory animals to both continuous wave (CW) and pulsed wave (PW) exposures, but the inconsistencies in these results, the failure to independently confirm corneal lesions after CW exposure, the failure to independently confirm retinal effects after PW exposure, and the absence of functional changes in vision are reasons why these ocular effects are not useful in defining an

  20. Differential Gene Expression in Explanted Human Retinal Pigment Epithelial Cells 12-Hours Post-Exposure to 532 nm, 120 ps Pulsed Laser Light

    DTIC Science & Technology

    2004-04-01

    years or younger, either sex, with no mitigating ocular or retinal pathology such as glaucoma, diabetic retinopathy, retinitis pigmentosa , etc. Donor: The...USAFA TR 2004-01 Differential Gene Expression in Explanted Human Retinal Pigment Epithelial Cells 12-hours Post-Exposure to 532 nm, 120 ps Pulsed...TR 2004-01 This article, "Differential Gene Expression in Explanted Human Retinal Pigment Epithelial Cells 12-hours Post-Exposure to 532 nm, 120 ps

  1. Lipid Nanoparticles for Ocular Gene Delivery

    PubMed Central

    Wang, Yuhong; Rajala, Ammaji; Rajala, Raju V. S.

    2015-01-01

    Lipids contain hydrocarbons and are the building blocks of cells. Lipids can naturally form themselves into nano-films and nano-structures, micelles, reverse micelles, and liposomes. Micelles or reverse micelles are monolayer structures, whereas liposomes are bilayer structures. Liposomes have been recognized as carriers for drug delivery. Solid lipid nanoparticles and lipoplex (liposome-polycation-DNA complex), also called lipid nanoparticles, are currently used to deliver drugs and genes to ocular tissues. A solid lipid nanoparticle (SLN) is typically spherical, and possesses a solid lipid core matrix that can solubilize lipophilic molecules. The lipid nanoparticle, called the liposome protamine/DNA lipoplex (LPD), is electrostatically assembled from cationic liposomes and an anionic protamine-DNA complex. The LPD nanoparticles contain a highly condensed DNA core surrounded by lipid bilayers. SLNs are extensively used to deliver drugs to the cornea. LPD nanoparticles are used to target the retina. Age-related macular degeneration, retinitis pigmentosa, and diabetic retinopathy are the most common retinal diseases in humans. There have also been promising results achieved recently with LPD nanoparticles to deliver functional genes and micro RNA to treat retinal diseases. Here, we review recent advances in ocular drug and gene delivery employing lipid nanoparticles. PMID:26062170

  2. Mucin characteristics of human corneal-limbal epithelial cells that exclude the rose bengal anionic dye.

    PubMed

    Argüeso, Pablo; Tisdale, Ann; Spurr-Michaud, Sandra; Sumiyoshi, Mika; Gipson, Ilene K

    2006-01-01

    Rose bengal is an organic anionic dye used to assess damage of the ocular surface epithelium in ocular surface disease. It has been proposed that mucins have a protective role, preventing rose bengal staining of normal ocular surface epithelial cells. The current study was undertaken to evaluate rose bengal staining in a human corneal-limbal epithelial (HCLE) cell line known to produce and glycosylate membrane-associated mucins. HCLE cells were grown to confluence in serum-free medium and switched to DMEM/F12 with 10% serum to promote differentiation. Immunolocalization of the membrane-associated mucins MUC1 and MUC16 and the T-antigen carbohydrate epitope was performed with the monoclonal antibodies HMFG-2 and OC125 and jacalin lectin, respectively. To assess dye uptake, cultures were incubated for 5 minutes with 0.1% rose bengal and photographed. To determine whether exclusion of negatively charged rose bengal requires a negative charge at the cell surface, cells were incubated with fluoresceinated cationized ferritin. The effect of hyperosmotic stress on rose bengal staining in vitro was evaluated by increasing the ion concentration (Ca+2 and Mg+2) in the rose bengal uptake assay. The cytoplasm and nucleus of confluent HCLE cells cultured in media without serum, lacking the expression of MUC16 but not MUC1, as well as human corneal fibroblasts, which do not express mucins, stained with rose bengal. Culture of HCLE cells in medium containing serum resulted in the formation of islands of stratified cells that excluded rose bengal. Apical cells of the stratified islands produced MUC16 and the T-antigen carbohydrate epitope on their apical surfaces. Colocalization experiments demonstrated that fluoresceinated cationized ferritin did not bind to these stratified cells, indicating that rose bengal is excluded from cells that lack negative charges. Increasing the amounts of divalent cations in the media reduced the cellular area protected against rose bengal uptake

  3. DynaMiTES - A dynamic cell culture platform for in vitro drug testing PART 2 - Ocular DynaMiTES for drug absorption studies of the anterior eye.

    PubMed

    Beiβner, Nicole; Mattern, Kai; Dietzel, Andreas; Reichl, Stephan

    2017-04-02

    In the present study, a formerly designed Dynamic Micro Tissue Engineering System (DynaMiTES) was applied with our prevalidated human hemicornea (HC) construct to obtain a test platform for improved absorption studies of the anterior eye (Ocular DynaMiTES). First, the cultivation procedure of the classic HC was slightly adapted to the novel DynaMiTES design. The obtained inverted HC was then compared to classic HC regarding cell morphology using light and scanning electron microscopy, cell viability using MTT dye reaction and epithelial barrier properties observing transepithelial electrical resistance and apparent permeation coefficient of sodium fluorescein. These tested cell criteria were similar. In addition, the effects of four different flow rates on the same cell characteristics were investigated using the DynaMiTES. Because no harmful potential of flow was found, dynamic absorption studies of sodium fluorescein with and without 0.005%, 0.01% and 0.02% benzalkonium chloride were performed compared to the common static test procedure. In this proof-of-concept study, the dynamic test conditions showed different results than the static test conditions with a better prediction of in vivo data. Thus, we propose that our DynaMiTES platform provides great opportunities for the improvement of common in vitro drug testing procedures. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Tissue resident memory T cells in the human conjunctiva and immune signatures in human dry eye disease

    PubMed Central

    Bose, Tanima; Lee, Ryan; Hou, Aihua; Tong, Louis; Chandy, K. George

    2017-01-01

    Non-recirculating resident memory (TRM) and recirculating T cells mount vigorous immune responses to both self and foreign antigens in barrier tissues like the skin, lung and gastrointestinal tract. Using impression cytology followed by flow cytometry we identified two TRM subsets and four recirculating T-subsets in the healthy human ocular surface. In dry eye disease, principal component analysis (PCA) revealed two clusters of patients with distinct T-cell signatures. Increased conjunctival central memory and naïve T cells characterized Cluster-1 patients, and increased CD8+ TRMs and CD4+ recirculating memory T cells characterized Cluster-2 patients. Interestingly these T-cell signatures are associated with different clinical features: the first signature correlated with increased ocular redness, and the second with reduced tear break up times. These findings open the door to immune-based characterization of dry eye disease and T-subset specific immunotherapies to suppress T-subsets involved in disease. They may also help with patient stratification during clinical trials of immunomodulators. PMID:28345628

  5. Tissue resident memory T cells in the human conjunctiva and immune signatures in human dry eye disease.

    PubMed

    Bose, Tanima; Lee, Ryan; Hou, Aihua; Tong, Louis; Chandy, K George

    2017-03-27

    Non-recirculating resident memory (TRM) and recirculating T cells mount vigorous immune responses to both self and foreign antigens in barrier tissues like the skin, lung and gastrointestinal tract. Using impression cytology followed by flow cytometry we identified two TRM subsets and four recirculating T-subsets in the healthy human ocular surface. In dry eye disease, principal component analysis (PCA) revealed two clusters of patients with distinct T-cell signatures. Increased conjunctival central memory and naïve T cells characterized Cluster-1 patients, and increased CD8(+) TRMs and CD4(+) recirculating memory T cells characterized Cluster-2 patients. Interestingly these T-cell signatures are associated with different clinical features: the first signature correlated with increased ocular redness, and the second with reduced tear break up times. These findings open the door to immune-based characterization of dry eye disease and T-subset specific immunotherapies to suppress T-subsets involved in disease. They may also help with patient stratification during clinical trials of immunomodulators.

  6. Suppression of the human vestibulo-ocular reflex by visual fixation or forced convergence in the dark, with a model interpretation.

    PubMed

    Gizzi, Martin S; Harper, Harry Wms

    2003-05-01

    Six normal humans experienced yaw axis steps of velocity at 120 degrees /s in the dark. During the post-rotary period, subjects either had a null-task (do nothing); an ocular motor task (forced convergence: crossing the eyes); or a visual task (fixating a head-stationary target against a background of 10 degrees light/dark bars). Tasks started at 3 s post-rotation, and lasted either 2, 5, 10, or 15 s. Ocular motor and visual tasks were tested on different days. Five repetitions of each task duration were recorded for each subject. A mean VOR gain of 0.52 was observed, which did not vary with experimental conditions. Both convergence and fixation markedly suppressed nystagmus; in fact, the VORs obtained with the two different tasks are superficially similar in appearance. However, mean null-task time-constants were 9.4 s for convergence days, but 8.4 s for fixation days, and there was a small but significant reduction in overall null-task VOR amplitude on fixation days. Also, post-convergence slow-phase velocities were slightly enhanced, while post-fixation velocities were significantly reduced. The time-constant of velocity storage was found to be 10.1 s for convergence responses and 8.2 s for fixation responses. These differences can be understood in terms of modifications in central velocity storage during visual fixation which do not occur with convergence. The mean fixation data were analyzed in the context of a VOR model well-established for monkey data. With appropriate choice of parameters, this model accurately reproduces most features of the human data. An estimate for the human cupula time-constant of 3.3 s is obtained. Compared with the monkey, fixation suppression is greater and post-fixation velocity reduction less. Retinal slip alone accounts well for this; "velocity dumping" by an integrator shunt must be slight if present at all. The model correctly represents the post-fixation VOR for all durations of fixation.

  7. Cultured Human Renal Cortical Cells

    NASA Technical Reports Server (NTRS)

    1998-01-01

    During the STS-90 shuttle flight in April 1998, cultured renal cortical cells revealed new information about genes. Timothy Hammond, an investigator in NASA's microgravity biotechnology program was interested in culturing kidney tissue to study the expression of proteins useful in the treatment of kidney diseases. Protein expression is linked to the level of differentiation of the kidney cells, and Hammond had difficulty maintaining differentiated cells in vitro. Intrigued by the improvement in cell differentiation that he observed in rat renal cells cultured in NASA's rotating wall vessel (a bioreactor that simulates some aspects of microgravity) and during an experiment performed on the Russian Space Station Mir, Hammond decided to sleuth out which genes were responsible for controlling differentiation of kidney cells. To do this, he compared the gene activity of human renal cells in a variety of gravitational environments, including the microgravity of the space shuttle and the high-gravity environment of a centrifuge. Hammond found that 1,632 genes out of 10,000 analyzed changed their activity level in microgravity, more than in any of the other environments. These results have important implications for kidney research as well as for understanding the basic mechanism for controlling cell differentiation.

  8. Cultured Human Renal Cortical Cells

    NASA Technical Reports Server (NTRS)

    1998-01-01

    During the STS-90 shuttle flight in April 1998, cultured renal cortical cells revealed new information about genes. Timothy Hammond, an investigator in NASA's microgravity biotechnology program was interested in culturing kidney tissue to study the expression of proteins useful in the treatment of kidney diseases. Protein expression is linked to the level of differentiation of the kidney cells, and Hammond had difficulty maintaining differentiated cells in vitro. Intrigued by the improvement in cell differentiation that he observed in rat renal cells cultured in NASA's rotating wall vessel (a bioreactor that simulates some aspects of microgravity) and during an experiment performed on the Russian Space Station Mir, Hammond decided to sleuth out which genes were responsible for controlling differentiation of kidney cells. To do this, he compared the gene activity of human renal cells in a variety of gravitational environments, including the microgravity of the space shuttle and the high-gravity environment of a centrifuge. Hammond found that 1,632 genes out of 10,000 analyzed changed their activity level in microgravity, more than in any of the other environments. These results have important implications for kidney research as well as for understanding the basic mechanism for controlling cell differentiation.

  9. Binding of betaxolol, metoprolol and oligonucleotides to synthetic and bovine ocular melanin, and prediction of drug binding to melanin in human choroid-retinal pigment epithelium.

    PubMed

    Pitkänen, Leena; Ranta, Veli-Pekka; Moilanen, Hanna; Urtti, Arto

    2007-11-01

    To characterize the binding of betaxolol, metoprolol and oligonucleotides to synthetic and bovine ocular melanin, and to predict the binding to melanin in human choroid-retinal pigment epithelium (RPE). The shape, size and specific surface area of synthetic melanin and isolated melanin granules from bovine choroid-retinal pigment epithelium (RPE) were characterized by SEM, laser diffractometry and BET. The binding of betaxolol, metoprolol, fluorescein isothiocyanate (FITC)-labeled phosphodiesther oligonucleotides and 6-carboxyfluorescein (6-CF) to melanin was determined. The binding of beta-blockers to melanin in human choroid-RPE was estimated based on binding parameters and the melanin content in human choroid-RPE. Bovine melanin granules were round or oval with a mean diameter of ca. 1 mum. Synthetic granules were slightly smaller and irregular and had a two times higher specific surface area than bovine melanin. Synthetic melanin bound more betaxolol and metoprolol than bovine melanin and both melanin types showed a high affinity and a low affinity binding sites. The human choroid-RPE was predicted to contain 3-19 times more melanin bound drug than unbound drug at typical therapeutic concentrations (1-1,000 ng/ml). FITC-labeled oligonucleotides and 6-CF did not bind to melanin. The binding of lipophilic drugs to biological melanin differs from that of synthetic melanin. Lipophilic beta-blockers are expected to bind significantly to melanin in human choroid-RPE: only a small fraction of the drug being in active free form. In contrast, phosphodiesther oligonucleotides do not seem to bind to melanin.

  10. Positive or negative feedback of optokinetic signals: degree of the misrouted optic flow determines system dynamics of human ocular motor behavior.

    PubMed

    Chen, Chien-Cheng; Bockisch, Christopher J; Olasagasti, Itsaso; Weber, Konrad P; Straumann, Dominik; Huang, Melody Ying-Yu

    2014-04-09

    The optokinetic system in healthy humans is a negative-feedback system that stabilizes gaze: slow-phase eye movements (i.e., the output signal) minimize retinal slip (i.e., the error signal). A positive-feedback optokinetic system may exist due to the misrouting of optic fibers. Previous studies have shown that, in a zebrafish mutant with a high degree of the misrouting, the optokinetic response (OKR) is reversed. As a result, slow-phase eye movements amplify retinal slip, forming a positive-feedback optokinetic loop. The positive-feedback optokinetic system cannot stabilize gaze, thus leading to spontaneous eye oscillations (SEOs). Because the misrouting in human patients (e.g., with a condition of albinism or achiasmia) is partial, both positive- and negative-feedback loops co-exist. How this co-existence affects human ocular motor behavior remains unclear. We presented a visual environment consisting of two stimuli in different parts of the visual field to healthy subjects. One mimicked positive-feedback optokinetic signals and the other preserved negative-feedback optokinetic signals. By changing the ratio and position of the visual field of these visual stimuli, various optic nerve misrouting patterns were simulated. Eye-movement responses to stationary and moving stimuli were measured and compared with computer simulations. The SEOs were correlated with the magnitude of the virtual positive-feedback optokinetic effect. We found a correlation among the simulated misrouting, the corresponding OKR, and the SEOs in humans. The proportion of the simulated misrouting needed to be greater than 50% to reverse the OKR and at least greater than or equal to 70% to evoke SEOs. Once the SEOs were evoked, the magnitude positively correlated to the strength of the positive-feedback OKR. This study provides a mechanism of how the misrouting of optic fibers in humans could lead to SEOs, offering a possible explanation for a subtype of infantile nystagmus syndrome (INS).

  11. Optical Properties of Ocular Tissues in the Near Infrared Region

    DTIC Science & Technology

    2006-01-01

    strongly absorbing.7 Construction of diagnostic or imaging devices for ocular diseases in the spectral range of interest will require a detailed...ocular fundus tissues - an in vitro study using the double-integrating-sphere technique and inverse Monte Carlo simulation," Phys. Med. Biol. 40, 963-978...reflectance of the human ocular fundus ," Appl. Opt. 28 (6), 1061-1077 (1989). 5 R.W. Knighton, S.G. Jacobson, and CM. Kemp, "The spectral reflectance of the

  12. Human ocular counter-rolling and roll tilt perception during off-vertical axis rotation after spaceflight.

    PubMed

    Clément, Gilles; Denise, Pierre; Reschke, Millard F; Wood, Scott J

    2007-01-01

    Ocular counter-rolling (OCR) induced by whole body tilt in roll has been explored after spaceflight as an indicator of the adaptation of the otolith function to microgravity. It has been claimed that the overall pattern of OCR responses during static body tilt after spaceflight is indicative of a decreased role of the otolith function, but the results of these studies have not been consistent, mostly due to large variations in the OCR within and across individuals. By contrast with static head tilt, off-vertical axis rotation (OVAR) presents the advantage of generating a sinusoidal modulation of OCR, allowing averaged measurements over several cycles, thus improving measurement accuracy. Accordingly, OCR and the sense of roll tilt were evaluated in seven astronauts before and after spaceflight during OVAR at 45 degrees/s in darkness at two angles of tilt (10 degrees and 20 degrees). There was no significant difference in OCR during OVAR immediately after landing compared to preflight. However, the amplitude of the perceived roll tilt during OVAR was significantly larger immediately postflight, and then returned to control values in the following days. Since the OCR response is predominantly attributed to the shearing force exerted on the utricular macula, the absence of change in OCR postflight suggests that the peripheral otolith organs function normally after short-term spaceflight. However, the increased sense of roll tilt indicates an adaptation in the central processing of gravitational input, presumably related to a re-weighting of the internal representation of gravitational vertical as a result of adaptation to microgravity.

  13. Influence of age, spatial memory, and ocular fixation on localization of auditory, visual, and bimodal targets by human subjects.

    PubMed

    Dobreva, Marina S; O'Neill, William E; Paige, Gary D

    2012-12-01

    A common complaint of the elderly is difficulty identifying and localizing auditory and visual sources, particularly in competing background noise. Spatial errors in the elderly may pose challenges and even threats to self and others during everyday activities, such as localizing sounds in a crowded room or driving in traffic. In this study, we investigated the influence of aging, spatial memory, and ocular fixation on the localization of auditory, visual, and combined auditory-visual (bimodal) targets. Head-restrained young and elderly subjects localized targets in a dark, echo-attenuated room using a manual laser pointer. Localization accuracy and precision (repeatability) were quantified for both ongoing and transient (remembered) targets at response delays up to 10 s. Because eye movements bias auditory spatial perception, localization was assessed under target fixation (eyes free, pointer guided by foveal vision) and central fixation (eyes fixed straight ahead, pointer guided by peripheral vision) conditions. Spatial localization across the frontal field in young adults demonstrated (1) horizontal overshoot and vertical undershoot for ongoing auditory targets under target fixation conditions, but near-ideal horizontal localization with central fixation; (2) accurate and precise localization of ongoing visual targets guided by foveal vision under target fixation that degraded when guided by peripheral vision during central fixation; (3) overestimation in horizontal central space (±10°) of remembered auditory, visual, and bimodal targets with increasing response delay. In comparison with young adults, elderly subjects showed (1) worse precision in most paradigms, especially when localizing with peripheral vision under central fixation; (2) greatly impaired vertical localization of auditory and bimodal targets; (3) increased horizontal overshoot in the central field for remembered visual and bimodal targets across response delays; (4) greater vulnerability to

  14. Diagnosis of Ocular Tuberculosis.

    PubMed

    Ang, Marcus; Vasconcelos-Santos, Daniel V; Sharma, Kusum; Accorinti, Massimo; Sharma, Aman; Gupta, Amod; Rao, Narsing A; Chee, Soon-Phaik

    2016-07-05

    Ocular tuberculosis remains a presumptive clinical diagnosis, as the gold standard tests for diagnosing ocular tuberculosis are often not useful: Mycobacterium tuberculosis cultures require weeks to process on Lowenstein-Jenson media and have low yield from ocular samples; while acid-fast bacilli smears or polymerase chain reaction detection of M. tuberculosis DNA have low sensitivities. Thus, diagnosis is often based on suggestive clinical signs, which are supported by positive investigations: tuberculin skin test or interferon-gamma release assays; chest X-ray findings suggestive of pulmonary tuberculosis, and/or evidence of associated systemic tuberculosis infections in the absence of other underlying disease. The aim of this review is to provide an update on the methods of diagnosing ocular tuberculosis, and discuss the challenges of its diagnosis. We also suggest a step-ladder approach to a more accurate diagnosis of ocular tuberculosis by combining the available diagnostic tests.

  15. Cytotoxicity assessment of porous silicon microparticles for ocular drug delivery.

    PubMed

    Korhonen, Eveliina; Rönkkö, Seppo; Hillebrand, Satu; Riikonen, Joakim; Xu, Wujun; Järvinen, Kristiina; Lehto, Vesa-Pekka; Kauppinen, Anu

    2016-03-01

    Porous silicon (PSi) is a promising material for the delivery and sustained release of therapeutic molecules in various tissues. Due to the constant rinsing of cornea by tear solution as well as the short half-life of intravitreal drugs, the eye is an attractive target for controlled drug delivery systems, such as PSi microparticles. Inherent barriers ensure that PSi particles are retained in the eye, releasing drugs at the desired speed until they slowly break down into harmless silicic acid. Here, we have examined the in vitro cytotoxicity of positively and negatively charged thermally oxidized (TOPSi) and thermally carbonized (TCPSi) porous silicon microparticles on human corneal epithelial (HCE) and retinal pigment epithelial (ARPE-19) cells. In addition to ocular assessment under an inverted microscope, cellular viability was evaluated using the CellTiter Blue™, CellTiter Fluor™, and lactate dehydrogenase (LDH) assays. CellTiter Fluor proved to be a suitable assay but due to non-specific and interfering responses, neither CellTiter Blue nor LDH assays should be used when evaluating PSi particles. Our results suggest that the toxicity of PSi particles is concentration-dependent, but at least at concentrations less than 200μg/ml, both positively and negatively charged PSi particles are well tolerated by human corneal and retinal epithelial cells and therefore applicable for delivering drug molecules into ocular tissues. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Human fetal mesenchymal stem cells.

    PubMed

    O'Donoghue, Keelin; Chan, Jerry

    2006-09-01

    Stem cells have been isolated at all stages of development from the early developing embryo to the post-reproductive adult organism. However, the fetal environment is unique as it is the only time in ontogeny that there is migration of stem cells in large numbers into different organ compartments. While fetal neural and haemopoietic stem cells (HSC) have been well characterised, only recently have mesenchymal stem cells from the human fetus been isolated and evaluated. Our group have characterised in human fetal blood, liver and bone marrow a population of non-haemopoietic, non-endothelial cells with an immunophenotype similar to adult bone marrow-derived mesenchymal stem cells (MSC). These cells, human fetal mesenchymal stem cells (hfMSC), are true multipotent stem cells with greater self-renewal and differentiation capacity than their adult counterparts. They circulate in first trimester fetal blood and have been found to traffic into the maternal circulation, engrafting in bone marrow, where they remain microchimeric for decades after pregnancy. Though fetal microchimerism has been implicated in the pathogenesis of autoimmune disease, the biological role of hfMSC microchimerism is unknown. Potential downstream applications of hfMSC include their use as a target cell for non-invasive pre-natal diagnosis from maternal blood, and for fetal cellular and gene therapy. Using hfMSC in fetal therapy offers the theoretical advantages of avoidance of immune rejection, increased engraftment, and treatment before disease pathology sets in. Aside from allogeneic hfMSC in utero transplantation, the use of autologous hfMSC has been brought a step forward with the development of early blood sampling techniques, efficient viral transduction and clonal expansion. Work is ongoing to determine hfMSC fate post-transplantation in murine models of genetic disease. In this review we will examine what is known about hfMSC biology, as well as discussing areas for future research. The

  17. Piceatannol Suppresses endotoxin-induced ocular inflammation in Rats

    PubMed Central

    Kalariya, Nilesh M.; Shoeb, Mohammad; Reddy, Aramati B. M.; Sawhney, Rahul; Ramana, Kota V.

    2013-01-01

    Anti-inflammatory effect of piceatannol, a naturally occurring polyphenol and a potent free radical scavenger, on ocular inflammation is not known. We examined the anti-inflammatory role of piceatannol in ocular inflammatory response due to endotoxin-induced uveitis (EIU) in rats. EIU was induced in Lewis rats by subcutaneous injection of lipopolysaccharide (LPS; 150 ug/rat). Piceatannol (30 mg/kg body wt, i.p) was injected either 2 h prior to or 1 h post LPS induction. A significant increase in the number of infiltrating cells, total protein, and various cytokines and chemokines in AqH were observed in the EIU rat eyes as compared to control groups. However, pre- or post- treatment of piceatannol significantly blocked the LPS-induced changes. Further, piceatannol also suppressed the expression of Cox-2, iNOS and activation of NF-κB in the ciliary bodies as well as retina. Further, piceatannol also inhibited the expression of Cox-2, iNOS, and phosphorylation of NF-κB in primary human non-pigmented ciliary epithelial cells (HNPECs) treated with LPS. Similarly, piceatannol also diminished LPS-induced level of NO and PGE2 in HNPECs. Thus our results demonstrate an anti-inflammatory role of piceatannol in suppressing ocular inflammation induced by endotoxin in rats. PMID:23892029

  18. Protective Effects of Human iPS-Derived Retinal Pigmented Epithelial Cells in Comparison with Human Mesenchymal Stromal Cells and Human Neural Stem Cells on the Degenerating Retina in rd1 mice.

    PubMed

    Sun, Jianan; Mandai, Michiko; Kamao, Hiroyuki; Hashiguchi, Tomoyo; Shikamura, Masayuki; Kawamata, Shin; Sugita, Sunao; Takahashi, Masayo

    2015-05-01

    Retinitis pigmentosa (RP) is a group of visual impairments characterized by progressive rod photoreceptor cell loss due to a genetic background. Pigment epithelium-derived factor (PEDF) predominantly secreted by the retinal pigmented epithelium (RPE) has been reported to protect photoreceptors in retinal degeneration models, including rd1. In addition, clinical trials are currently underway outside Japan using human mesenchymal stromal cells and human neural stem cells to protect photoreceptors in RP and dry age-related macular degeneration, respectively. Thus, this study aimed to investigate the rescue effects of induced pluripotent stem (iPS)-RPE cells in comparison with those types of cells used in clinical trials on photoreceptor degeneration in rd1 mice. Cells were injected into the subretinal space of immune-suppressed 2-week-old rd1 mice. The results demonstrated that human iPS-RPE cells significantly attenuated photoreceptor degeneration on postoperative days (PODs) 14 and 21 and survived longer up to at least 12 weeks after operation than the other two types of graft cells with less immune responses and apoptosis. The mean PEDF concentration in the intraocular fluid in RPE-transplanted eyes was more than 1 µg/ml at PODs 14 and 21, and this may have contributed to the protective effect of RPE transplantation. Our findings suggest that iPS-RPE cells serve as a competent source to delay photoreceptor degeneration through stable survival in degenerating ocular environment and by releasing neuroprotective factors such as PEDF.

  19. Prevalence of ocular manifestations of HIV/AIDS in the highly active antiretroviral therapy (HAART) era: a different spectrum in Central South China.

    PubMed

    Luo, Jing; Jing, Deng; Kozak, Igor; Huiming, Zhang; Siying, Chen; Yezhen, Yang; Xin, Qi; Luosheng, Tang; Adelman, Ron A; Forster, Susan H

    2013-06-01

    To investigate ocular manifestations of human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) in a population in central south China during a time of highly active antiretroviral therapy (HAART). A cross-sectional study in central south China was performed between June 2009 and April 2010. Ocular examinations were performed on recruited patients with HIV/AIDS. Systemic information (including CD4+ T cell count) was also collected where possible. Among 1041 patients (2082 eyes) with HIV/AIDS enrolled in our study, we found a broad spectrum of ocular manifestations related to HIV/AIDS. The prevalence of HIV-associated ocular disease was 23.73% (247 patients). Of those with ocular complications, 87.85% had CD4 counts <200 cells/µL. HIV retinopathy (12.68%) was the most common HIV-associated ocular finding, followed by cytomegalovirus retinitis (6.72%). Prevalences of visual impairment and blindness were 7.59% and 0.77%, respectively. This epidemiologic study shows the spectrum of ocular lesions associated with HIV/AIDS in central south China. Our findings highlight the need for routine ophthalmic examinations in this population, even in patients who are asymptomatic, especially those at high risk, in the era of HAART.

  20. Human stem cell ethics: beyond the embryo.

    PubMed

    Sugarman, Jeremy

    2008-06-05

    Human embryonic stem cell research has elicited powerful debates about the morality of destroying human embryos. However, there are important ethical issues related to stem cell research that are unrelated to embryo destruction. These include particular issues involving different types of cells used, the procurement of such cells, in vivo use of stem cells, intellectual property, and conflicts of interest.

  1. Differentiated human stem cells resemble fetal, not adult, β cells.

    PubMed

    Hrvatin, Sinisa; O'Donnell, Charles W; Deng, Francis; Millman, Jeffrey R; Pagliuca, Felicia Walton; DiIorio, Philip; Rezania, Alireza; Gifford, David K; Melton, Douglas A

    2014-02-25

    Human pluripotent stem cells (hPSCs) have the potential to generate any human cell type, and one widely recognized goal is to make pancreatic β cells. To this end, comparisons between differentiated cell types produced in vitro and their in vivo counterparts are essential to validate hPSC-derived cells. Genome-wide transcriptional analysis of sorted insulin-expressing (INS(+)) cells derived from three independent hPSC lines, human fetal pancreata, and adult human islets points to two major conclusions: (i) Different hPSC lines produce highly similar INS(+) cells and (ii) hPSC-derived INS(+) (hPSC-INS(+)) cells more closely resemble human fetal β cells than adult β cells. This study provides a direct comparison of transcriptional programs between pure hPSC-INS(+) cells and true β cells and provides a catalog of genes whose manipulation may convert hPSC-INS(+) cells into functional β cells.

  2. Interleukin-6 participation in pathology of ocular diseases.

    PubMed

    Zahir-Jouzdani, Forouhe; Atyabi, Fatemeh; Mojtabavi, Nazanin

    2017-09-01

    Interleukin-6 (IL-6) is a multifunctional cytokine that affects a variety of cells in the body such as osteoclasts, hepatocytes, endothelial cells, epithelial cells, white and red blood cells and etc. Elevated levels of IL-6 have been detected in many ocular diseases. Studies show that IL-6 has a major role in the pathology of glaucoma, CRVO, macular edema, ocular neovascularization, posterior capsule opacity formation, keratitis, dry eye disease, allergic eye disease, ocular autoimmune disease, corneal chemical burn, ocular inflammation and so on. IL-6 does its effects through the classic or trans-signal pathways in cells. Blocking of IL-6 signal pathways via Tocilizumab or other chemicals and therapeutics will help to overcome complications related to ocular diseases. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Characterization of the varicella zoster virus (VZV)-specific intra-ocular T-cell response in patients with VZV-induced uveitis.

    PubMed

    Milikan, Johannes C M; Kuijpers, Robert W A M; Baarsma, G Seerp; Osterhaus, Albert D M E; Verjans, Georges M G M

    2006-07-01

    Varicella zoster virus (VZV) is a well-known cause of infectious uveitis. The aim of this study was to characterize the VZV-specific T-cell response in eyes of patients with VZV-induced uveitis. T-cell lines (TCL) were generated by mitogenic stimulation of intra-ocular fluid (IOF) samples obtained from eight patients with VZV-induced uveitis. Two patients with herpes simplex virus (HSV)-induced uveitis were included as disease controls. Characterization of individual T-cells in the TCL was performed by stimulating the TCL with mock, HSV-1 and VZV antigen pulsed autologous B cells and subsequent flow cytometric analyses. Virus specificity and phenotype of the T-cells were identified by simultaneous detection of intracellular gamma interferon and cell surface markers CD4, CD8, CD3 or T-cell receptor (TCR) beta chain variable region (TCRBV) usage. The TCL obtained from patients with HSV-1-induced uveitis contained higher numbers of T-cells reactive to HSV-1 compared to VZV. VZV-specific T-cells were detected in all TCL of the patients diagnosed with VZV-induced uveitis. Four out of six TCL obtained from patients with VZV-induced uveitis that were assayed for both viruses, contained higher numbers of T-cells reactive to VZV compared to HSV-1. Detailed analyses of the TCL of two patients demonstrated that the VZV reactivity within the assayed TCL was dominated by T-cells expressing one specific TCRBV gene. The data implicate that VZV-reactive T-cells infiltrate and participate in the local inflammatory response in eyes of patients with VZV-induced uveitis.

  4. Clinical manifestations and cerebrospinal fluid status in ocular syphilis in HIV-Negative patients.

    PubMed

    Dai, Ting; Wu, Xinjun; Zhou, Shaona; Wang, Qianqiu; Li, Daning

    2016-06-06

    Syphilis with ocular involvement has reemerged as a critical health problem. The aim of the present study was to explore the clinical manifestations and cerebrospinal fluid (CSF) status in ocular syphilis in human immunodeficiency virus (HIV)-negative patients. The clinical records of patients with ocular syphilis presenting to the Shanghai Xuhui Central Hospital in the period from January 2011 to December 2012 were retrospectively reviewed. The median age of 25 HIV-negative patients with ocular syphilis was 53 years, 18 patients (72.0 %) were males and 7 (28.0 %) were females. None of them self-identified themselves as men who had sex with men (MSM). The ocular lesions included: uveitis (13 cases), optic neuropathy (6 cases), retinal vasculitis (5 cases), retinal detachment (3 cases), and neuroretinitis (4 cases). Serum toluidine red unheated serum test (TRUST) titer ranged from 1 to 512, with a median of 64. Overall, 18 (72.0 %) of the 25 patients had abnormal CSF results, 15 (60.0 %) CSF samples had elevated white blood cell counts, 13 (52.0 %) had elevated protein levels, and 9 (36.0 %) had reactive CSF Venereal Disease Research Laboratory (VDRL) test, respectively. Mann-Whitney U tests showed higher serum TRUST titer (>32) correlated with the abnormal CSF results. The demographic characteristics of patients with ocular syphilis in this study were different from previous reports. The study showed a high CSF abnormal rate in HIV-negative patients. The recommendation for CSF examination from all patients with ocular syphilis, including HIV-negative cases, is strongly supported by the present data.

  5. Embryonic stem cell patents and human dignity.

    PubMed

    Resnik, David B

    2007-09-01

    This article examines the assertion that human embryonic stem cells patents are immoral because they violate human dignity. After analyzing the concept of human dignity and its role in bioethics debates, this article argues that patents on human embryos or totipotent embryonic stem cells violate human dignity, but that patents on pluripotent or multipotent stem cells do not. Since patents on pluripotent or multipotent stem cells may still threaten human dignity by encouraging people to treat embryos as property, patent agencies should carefully monitor and control these patents to ensure that patents are not inadvertently awarded on embryos or totipotent stem cells.

  6. Embryonic Stem Cell Patents and Human Dignity

    PubMed Central

    Resnik, David B.

    2009-01-01

    This article examines the assertion that human embryonic stem cells patents are immoral because they violate human dignity. After analyzing the concept of human dignity and its role in bioethics debates, this article argues that patents on human embryos or totipotent embryonic stem cells violate human dignity, but that patents on pluripotent or multipotent stem cells do not. Since patents on pluripotent or multipotent stem cells may still threaten human dignity by encouraging people to treat embryos as property, patent agencies should carefully monitor and control these patents to ensure that patents are not inadvertently awarded on embryos or totipotent stem cells. PMID:17922198

  7. Antibiotic resistance in ocular bacterial pathogens.

    PubMed

    Sharma, S

    2011-01-01

    Bacterial infections of the eye are common and ophthalmologists are spoilt for choice with a variety of antibiotics available in the market. Antibiotics can be administered in the eye by a number of routes; topical, subconjunctival, subtenon and intraocular. Apart from a gamut of eye drops available, ophthalmologists also have the option of preparing fortified eye drops from parenteral formulations, thereby, achieving high concentrations; often much above the minimum inhibitory concentration (MIC), of antibiotics in ocular tissues during therapy. Antibiotic resistance among ocular pathogens is increasing in parallel with the increase seen over the years in bacteria associated with systemic infections. Although it is believed that the rise in resistant ocular bacterial isolates is linked to the rise in resistant systemic pathogens, recent evidence has correlated the emergence of resistant bacteria in the eye to prior topical antibiotic therapy. One would like to believe that either of these contributes to the emergence of resistance to antibiotics among ocular pathogens. Until recently, ocular pathogens resistant to fluoroquinolones have been minimal but the pattern is currently alarming. The new 8-fluoroquinolone on the scene-besifloxacin, is developed exclusively for ophthalmic use and it is hoped that it will escape the selective pressure for resistance because of lack of systemic use. In addition to development of new antibacterial agents, the strategies to halt or control further development of resistant ocular pathogens should always include judicious use of antibiotics in the treatment of human, animal or plant diseases.

  8. Albinism: particular attention to the ocular motor system.

    PubMed

    Hertle, Richard W

    2013-01-01

    The purpose of this report is to summarize an understanding of the ocular motor system in patients with albinism. Other than the association of vertical eccentric gaze null positions and asymmetric, (a) periodic alternating nystagmus in a large percentage of patients, the ocular motor system in human albinism does not contain unique pathology, rather has "typical" types of infantile ocular oscillations and binocular disorders. Both the ocular motor and afferent visual system are affected to varying degrees in patients with albinism, thus, combined treatment of both systems will maximize visual function.

  9. Albinism: Particular Attention to the Ocular Motor System

    PubMed Central

    Hertle, Richard W.

    2013-01-01

    The purpose of this report is to summarize an understanding of the ocular motor system in patients with albinism. Other than the association of vertical eccentric gaze null positions and asymmetric, (a) periodic alternating nystagmus in a large percentage of patients, the ocular motor system in human albinism does not contain unique pathology, rather has “typical” types of infantile ocular oscillations and binocular disorders. Both the ocular motor and afferent visual system are affected to varying degrees in patients with albinism, thus, combined treatment of both systems will maximize visual function. PMID:24014991

  10. In Silico Ocular Pharmacokinetic Modeling: Delivery of Topical FK962 to Retina.

    PubMed

    Mori, Ayumi; Yabuta, Chiho; Kishimoto, Yayoi; Kozai, Seiko; Ohtori, Akira; Shearer, Thomas R; Azuma, Mitsuyoshi

    2017-09-01

    To establish the in silico ocular pharmacokinetic modeling for eye drops, and to simulate the dose regimen for FK962 in human choroid/retinal diseases. Pharmacokinetics for FK962 in vivo was performed by a single instillation of drops containing 0.1% (14)C-FK962 in rabbit eyes. Permeation of FK962 across the cornea, sclera, and choroid/retina was measured in vitro. Neurite elongation by FK962 was measured in cultured rat retinal ganglion cells. Parameters from the experimental data were used in an improved in silico model of ocular pharmacokinetics of FK962 in man. The mean concentration of FK962 in ocular tissues predicted by in silico modeling was consistent with in vivo results, validating the in silico model. FK962 rapidly penetrated into the anterior and posterior segments of the eye and then diffused into the vitreous body. The in silico pharmacokinetic modeling also predicted that a dose regimen of 0.0054% FK962 twice per day would produce biologically effective concentrations of FK962 in the choroid/retina, where FK962 facilitates rat neurite elongation. Our in silico model for ocular pharmacokinetics is useful (1) for predicting drug concentrations in specific ocular tissues after topical instillation, and (2) for suggesting the optimal dose regimens for eye drops. The pharmacodynamics for FK962 produced by this model may be useful for clinical trials against retinal neuropathy.

  11. Ocular Emergencies: Red Eye.

    PubMed

    Tarff, Andreina; Behrens, Ashley

    2017-05-01

    "Red eye" is used as a general term to describe irritated or bloodshot eyes. It is a recognizable sign of an acute/chronic, localized/systemic underlying inflammatory condition. Conjunctival injection is most commonly caused by dryness, allergy, visual fatigue, contact lens overwear, and local infections. In some instances, red eye can represent a true ocular emergency that should be treated by an ophthalmologist. A comprehensive assessment of red eye conditions is required to preserve the patients visual function. Severe ocular pain, significant photophobia, decreased vision, and history of ocular trauma are warning signs demanding immediate ophthalmological consultation. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Localisation of Epithelial Cells Capable of Holoclone Formation In Vitro and Direct Interaction with Stromal Cells in the Native Human Limbal Crypt

    PubMed Central

    Dziasko, Marc A.; Armer, Hannah E.; Levis, Hannah J.; Shortt, Alex J.; Tuft, Stephen; Daniels, Julie T.

    2014-01-01

    Limbal epithelial stem cells (LESCs) are essential to maintain the transparent ocular surface required for vision. Despite great advances in our understanding of ocular stem cell biology over the last decade, the exact location of the LESC niche remains unclear. In the present study we have used in vitro clonal analysis to confirm that limbal crypts provide a niche for the resident LESCs. We have used high-resolution imaging of the basal epithelial layer at the limbus to identify cells with a morphology consistent with stem cells that were only present within the basal layer of the limbal crypts. These cells are proximal to limbal stromal cells suggesting direct cell-to-cell interaction. Serial block-face scanning electron microscopy (SBFSEM) confirmed that the putative LESCs are indeed in direct contact with cells in the underlying stroma, a contact that is facilitated by focal basement membrane interruptions. Limbal mesenchymal cells previously identified in the human limbus collocate in the crypt-rich limbal stromal area in the vicinity of LESCs and may be involved in the cell-to-cell contact revealed by SBFSEM. We also observed a high population of melanocytes within the basal layer of the limbal crypts. From these observations we present a three dimensional reconstruction of the LESC niche in which the stem cell is closely associated and maintained by both dendritic pigmented limbal melanocytes and elongated limbal stromal cells. PMID:24714106

  13. FTY720 ameliorates Dry Eye Disease in NOD mice: Involvement of leukocytes inhibition and goblet cells regeneration in ocular surface tissue.

    PubMed

    Xiao, Weibao; Xu, Guo-Tong; Zhang, Jingfa; Zhang, Jiaying; Zhang, Yu; Ye, Wen

    2015-09-01

    FTY720 is a promising drug in attenuating multiple sclerosis, prolonging survival of organ allograft, and many other protective effects. Its mechanism of action is considered to be mediated by the internalization of sphingosine 1-phosphate receptors (S1PRs). In the current study, we investigated the efficacy of FTY720 in Non-Obese Diabetic (NOD) mice, serving as a model of Dry Eye Disease (DED). NOD mice were divided into six study groups, i.e., FTY720-treated groups with 3 concentrations of FTY720 (0.05%, 0.005%, and 0.001%), 0.05% Cyclosporin A (CsA) treated group, normal saline treated group, and no treatment control group. FTY720 was reconstituted with normal saline and prepared as eye drop. The stability and production of tear film was measured by Tear Break up Time test (TBUT) and phenol red cotton thread test (PRCTT), respectively. Tear fluid washings were collected and assessed by ELISA. Cytokines were detected in lacrimal glands by RT-PCR. Inflammation in conjunctiva was assessed by immunohistochemistry, goblet cells and conjunctival epithelia were examined and evaluated by impression cytology. Our results indicated that FTY720 had a significantly therapeutic effect in NOD mice. After FTY720 intervention, TBUT and PRCTT data were greatly improved (p < 0.01), the interleukin 1β (IL-1β) level was markedly decreased in tear fluid washings compared to control and normal saline groups after 2 weeks ( 1.06 ± 0.12, Normal saline:0.97 ± 0.09 pg/ml, CsA:0.22 ± 0.02 pg/ml, 0.001% FTY720:0.23 ± 0.02 pg/ml, 0.005% FTY720:0.14 ± 0.03 pg/ml, 0.05% FTY720: 0.18 ± 0.03 pg/ml. CsA group and 3 FTY720 groups VS. control group and normal saline groups: p < 0.01). Proinflammatory factors were greatly decreased in lacrimal glands (p < 0.01). Leukocytes were identified and markedly decreased in conujnctiva (p < 0.01), inflammatory reaction of DED was greatly relieved. More importantly, the goblet cells were largely restored and ocular surface

  14. Ocular nerve growth factor administration counteracts the impairment of neural precursor cell viability and differentiation in the brain subventricular area of rats with streptozotocin-induced diabetes.

    PubMed

    Tirassa, Paola; Maccarone, Mattia; Carito, Valentina; De Nicolò, Sara; Fiore, Marco

    2015-05-01

    The ocular administration of nerve growth factor (NGF) as eye drops (oNGF) has been shown to exert protective effects in forebrain-injured animal models, including adult diabetes induced by a single injection of streptozotocin (STZ) (60 mg/kg body weight). This type 1 diabetes model was used in this study to investigate whether oNGF might extend its actions on neuronal precursors localised in the subventricular zone (SVZ). NGF or saline was administrated as eye drops twice daily for 2 weeks in rats with STZ-induced diabetes and healthy control rats. The expression of mature and precursor NGF and the NGF receptors, tropomyosin-related kinase A and neurotrophin receptor p75, and the levels of DNA fragmentation were analysed by ELISA and western blotting. Incorporation of bromodeoxyuridine was used to trace newly formed cells. Nestin, polysialylated neuronal cell adhesion molecule (PSA-NCAM), doublecortin (DCX) and glial fibrillary acidic protein antibodies were used to identify the SVZ cells by confocal microscopy. It was found that oNGF counteracts the STZ-induced cell death and the alteration of mature/pro-NGF expression in the SVZ. It also affects the survival and differentiation of SVZ progenitors. In particular, oNGF counteracts the reduction in the number of cells expressing PSA-NCAM/DCX (neuroblast type A cells) and the related redu