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Sample records for corneal angiogenic privilege

  1. AP-2β Is a Downstream Effector of PITX2 Required to Specify Endothelium and Establish Angiogenic Privilege During Corneal Development.

    Science.gov (United States)

    Chen, Lisheng; Martino, Vanessa; Dombkowski, Alan; Williams, Trevor; West-Mays, Judith; Gage, Philip J

    2016-03-01

    The homeodomain transcription factor, PITX2, is at the apex of a genetic pathway required for corneal development, but the critical effector genes regulated by the PITX2 remain unknown. The purpose of this study was to discover and validate PITX2-dependent mechanisms required for specifying cell lineages and establishing angiogenic privilege within the developing cornea. Microarrays were used to compare gene expression in corneas isolated from temporal Pitx2 knockout embryos and control littermates. Quantitative RT-PCR and immunohistochemistry was used to further validate Tfap2b expression differences in Pitx2 knockout versus control corneas. In situ hybridization and protein immunohistochemistry were used to assay eyes of a Tfap2b allelic series of embryos to identify differentiated cellular lineages in the cornea, blood vessel endothelium, or lymphatic vessel endothelium. We show that PITX2 is required for the expression of Tfap2b, encoding the AP-2β transcription factor, in the neural crest during corneal development. Markers of differentiated corneal epithelium and stroma are expressed in the absence of AP-2β. In contrast, markers of differentiated corneal endothelium are not expressed in the absence of AP-2β. Endomucin+ blood vessels are present throughout the developing corneal stroma in the absence of AP-2β, whereas LYVE1+ lymphatic vessels are not found. The AP-2β transcription factor is an important effector of PITX2 function during corneal development, required for differentiation of corneal endothelium and establishment of angiogenic privilege. Unlike PITX2, AP-2β is not required for the early expression of available lineage specific markers for the corneal epithelium and stroma during embryogenesis, nor establishment of lymphangiogenic privilege. Therefore, additional PITX2-dependent factors likely regulate these latter processes during embryonic development. These results extend our understanding of the genetic mechanisms regulating cornea

  2. The homeodomain transcription factor PITX2 is required for specifying correct cell fates and establishing angiogenic privilege in the developing cornea.

    Science.gov (United States)

    Gage, Philip J; Kuang, Chen; Zacharias, Amanda L

    2014-11-01

    Correct specification of cell lineages and establishing angiogenic privilege within the developing cornea are essential for normal vision but the mechanisms controlling these processes are poorly understood. We show that the homeodomain transcription factor PItX2 is expressed in mesenchymal cells of the developing and mature cornea and use a temporal gene knockout approach to demonstrate that PITX2 is required for corneal morphogenesis and the specification of cell fates within the surface ectoderm and mesenchymal primordia. PITX2 is also required to establish angiogenic privilege in the developing cornea. Further, the expression of Dkk2 and suppression of canonical Wnt signaling activity levels are key mechanisms by which PITX2 specifies ocular surface ectoderm as cornea. In contrast, specifying the underlying mesenchyme to corneal fates and establishing angiogenic privilege in the cornea are less sensitive to DKK2 activity. Finally, the cellular expression patterns of FOXC2, PITX1, and BARX2 in Pitx2 and Dkk2 mutants suggest that these transcription factors may be involved in specifying cell fate and establishing angiogenic privilege within the corneal mesenchyme. However, they are unlikely to play a role in specifying cell fate within the corneal ectoderm. Together, these data provide important insights into the mechanisms regulating cornea development. Copyright © 2014 Wiley Periodicals, Inc.

  3. Kinetics of Angiogenic Responses in Corneal Transplantation.

    Science.gov (United States)

    Inomata, Takenori; Mashaghi, Alireza; Di Zazzo, Antonio; Lee, Sang-Mok; Chiang, Homer; Dana, Reza

    2017-04-01

    To delineate and compare the kinetics of corneal angiogenesis after high-risk (HR) versus low-risk (LR) corneal transplantation. In mice, intrastromal sutures were placed in the recipient graft bed 2 weeks before allogeneic transplantation to induce angiogenesis and amplify the risk of graft rejection. Control (LR) graft recipients did not undergo suture placement, and thus the host bed remained avascular at the time of transplantation. Graft hemangiogenesis and opacity scores were evaluated for 8 weeks by slit-lamp biomicroscopy. Immunohistochemistry was used to measure CD31 (blood vessels) and LYVE-1 (lymphatic vessels) cells. Biphasic kinetics were observed for hemangiogenesis in both HR and LR transplant recipients using clinical and immunohistochemical assessments. The biphasic kinetics were composed of a rise-fall (phase 1) followed by a second rise (phase 2) in the degree of vessels. Compared with LR recipients, HR recipients showed higher hemangiogenesis (whole cornea and graft) throughout 8 weeks. Analyzing grafts revealed sustained presence of lymphatic vessels in HR recipients; however, lymphatic neovessels regressed in LR recipients 2 weeks posttransplantation. In contrast to HR host beds, the LR host bed microenvironment cannot sustain the growth of lymphatic neovessels in allografts, whereas it can sustain continued hemangiogenesis. The sustained presence of lymphatic vessels in HR host beds can facilitate host immunity against allografts and is likely associated with ongoing higher risk of rejection of these grafts in the long term, suggesting that therapeutic interventions targeting inflammation and lymphatic vessels need to be sustained long term in the HR corneal transplant setting.

  4. The induction of an angiogenic response in corneal myofibroblasts by platelet-activating factor (PAF).

    Science.gov (United States)

    He, Jiucheng; Eastlack, Jason P; Bazan, Haydee E P

    2010-12-01

    Although the exact mechanisms underlying corneal neovascularization remain unclear, cytokines and growth factors play an important role in their development. We have shown previously that the inflammatory mediator platelet-activating factor (PAF) is a potent inducer of corneal neovascularization in vivo. In this study, we investigate the role of stromal myofibroblasts in neovascularization and the effect of PAF on this process. Myofibroblasts were obtained from rabbit corneal keratocytes and identified with anti-α-SMA antibody. Cells were treated with PAF (100 nM) for 24 hr. In some experiments, cells were pre-treated with the PAF antagonist LAU-0901 (150 nM). Expression of vascular endothelial growth factor (VEGF) and thrombospondin-1 (TSP-1) was examined by immunofluorescence and immunoblotting. To study the effect of myofibroblasts on vessel formation in vitro, Vybrant(®) CM-DiI labeled human umbilical vein endothelial cells (HUVECs) were cultured on myofibroblasts in a thin layer of collagen gel. CD31 was used as the cell marker of HUVEC. VEGF and TSP-1 were not detectable in keratocytes, but they were positively stained in myofibroblasts. PAF induced a significant increase in VEGF expression and a decrease in TSP-1 expression. These changes were inhibited in the presence of LAU-0901. HUVECs co-cultured with corneal myofibroblasts formed a typical structure of vessel-like tubes within 1 week. The addition of PAF to the medium increased HUVEC-induced vessel-like tube formation, which was abolished by LAU-0901. Addition of anti-VEGF antibody to the medium completely prevented the formation of vessel-like tubes. We provide evidence for the role of stromal myofibroblasts in the corneal neovascularization process. By enhancing VEGF production and decreasing TSP-1 production in myofibroblasts, PAF augments the angiogenic response. The PAF antagonist LAU-0901 could represent a new therapeutic venue for inhibiting corneal neovascularization.

  5. Protective Role of ICOS and ICOS Ligand in Corneal Transplantation and in Maintenance of Immune Privilege.

    Science.gov (United States)

    Kunishige, Tomoyuki; Taniguchi, Hiroko; Terada, Misao; Akiba, Hisaya; Yagita, Hideo; Abe, Ryo; Hori, Junko

    2016-12-01

    The interaction between the inducible costimulatory molecule (ICOS) and ICOS ligand (ICOSL) has been implicated in the differentiation and functions of T cells. The purpose of the present study was to determine the role of ICOS-ICOSL in the immune privilege of corneal allografts. Expression of ICOS and ICOSL mRNA from mouse eyes was assessed by RT-PCR. Corneas of C57BL/6 mice were orthotopically transplanted into the eyes of ICOS-/- BALB/c recipients and BALB/c wild-type (WT) recipients treated with anti-ICOSL mAb, and graft survival was assessed. A separate set of WT and ICOS-/- BALB/c mice received an anterior chamber injection of C57BL/6 splenocytes, and induction of allospecific anterior chamber-associated immune deviation (ACAID) was assessed. In vitro, cornea was incubated with T cells from WT and ICOS-/- BALB/c mice, and destruction of corneal endothelial cells (CECs) and the population of Foxp3+ CD25+ CD4+ T cells was assessed. Inducible costimulatory molecule ligand mRNA was constitutively expressed in the cornea, iris-ciliary body, and retina. Allograft survival in ICOS-/- recipients and WT recipients treated with anti-ICOSL mAb was significantly shorter than in control recipients. Anterior chamber-associated immune deviation was induced less efficiently in ICOS-/- mice. Destruction of CECs by alloreactive ICOS-/- T cells was enhanced compared with WT T cells. After coincubation with allogeneic corneal tissue, the proportion of regulatory T cells was significantly greater among WT T cells than in ICOS-/- T cells. The expression of ICOSL in the cornea and the ICOS-mediated induction of Foxp3+ CD4+ regulatory T cells may contribute to successful corneal allograft survival.

  6. Privilege

    Directory of Open Access Journals (Sweden)

    Luciana Manfredi

    2006-01-01

    Full Text Available Privilege, es la marca con la que la familia Jaramillo se lanzó al mercado caleño, ofreciendo ropa sobre medida y talla para hombres y mujeres, con altos estándares de calidad, servicio personalizado y diseños de moda; su portafolio de productos incluye ropa formal y casual para ejecutivos(as. Esta marca, pese a no tener competidores directos, sí observaba que algunas marcas y diseñadores exclusivos se encontraban dentro del grupo de consideración de los consumidores objetivo de Privilege. La gerencia de la compañía enfrenta costos fijos elevados (ocupación de maquinaria al 50% que afectan la rentabilidad; un nuevo punto de venta que presenta promedio de ingresos inferiores a los necesarios para su autosostenibilidad; bajo reconocimiento de marca por parte del target, competidores con gran músculo financiero y marcas altamente reconocidas con trayectoria y precios competitivos.

  7. Family Privilege

    Science.gov (United States)

    Seita, John R.

    2014-01-01

    Family privilege is defined as "strengths and supports gained through primary caring relationships." A generation ago, the typical family included two parents and a bevy of kids living under one roof. Now, every variation of blended caregiving qualifies as family. But over the long arc of human history, a real family was a…

  8. Corneal Laceration

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    Full Text Available ... What Is Corneal Laceration? Corneal Laceration Symptoms What Causes Corneal Laceration? Corneal Laceration Diagnosis Corneal Laceration Treatment ... the corneal laceration is deep enough it can cause a full thickness laceration. This is when the ...

  9. Corneal Laceration

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    Full Text Available ... What Is Corneal Laceration? Corneal Laceration Symptoms What Causes Corneal Laceration? Corneal Laceration Diagnosis Corneal Laceration Treatment What Is Corneal Laceration? Leer en Español: ¿Qué ...

  10. Corneal avascularity is due to soluble VEGF receptor-1.

    Science.gov (United States)

    Ambati, Balamurali K; Nozaki, Miho; Singh, Nirbhai; Takeda, Atsunobu; Jani, Pooja D; Suthar, Tushar; Albuquerque, Romulo J C; Richter, Elizabeth; Sakurai, Eiji; Newcomb, Michael T; Kleinman, Mark E; Caldwell, Ruth B; Lin, Qing; Ogura, Yuichiro; Orecchia, Angela; Samuelson, Don A; Agnew, Dalen W; St Leger, Judy; Green, W Richard; Mahasreshti, Parameshwar J; Curiel, David T; Kwan, Donna; Marsh, Helene; Ikeda, Sakae; Leiper, Lucy J; Collinson, J Martin; Bogdanovich, Sasha; Khurana, Tejvir S; Shibuya, Masabumi; Baldwin, Megan E; Ferrara, Napoleone; Gerber, Hans-Peter; De Falco, Sandro; Witta, Jassir; Baffi, Judit Z; Raisler, Brian J; Ambati, Jayakrishna

    2006-10-26

    Corneal avascularity-the absence of blood vessels in the cornea-is required for optical clarity and optimal vision, and has led to the cornea being widely used for validating pro- and anti-angiogenic therapeutic strategies for many disorders. But the molecular underpinnings of the avascular phenotype have until now remained obscure and are all the more remarkable given the presence in the cornea of vascular endothelial growth factor (VEGF)-A, a potent stimulator of angiogenesis, and the proximity of the cornea to vascularized tissues. Here we show that the cornea expresses soluble VEGF receptor-1 (sVEGFR-1; also known as sflt-1) and that suppression of this endogenous VEGF-A trap by neutralizing antibodies, RNA interference or Cre-lox-mediated gene disruption abolishes corneal avascularity in mice. The spontaneously vascularized corneas of corn1 and Pax6+/- mice and Pax6+/- patients with aniridia are deficient in sflt-1, and recombinant sflt-1 administration restores corneal avascularity in corn1 and Pax6+/- mice. Manatees, the only known creatures uniformly to have vascularized corneas, do not express sflt-1, whereas the avascular corneas of dugongs, also members of the order Sirenia, elephants, the closest extant terrestrial phylogenetic relatives of manatees, and other marine mammals (dolphins and whales) contain sflt-1, indicating that it has a crucial, evolutionarily conserved role. The recognition that sflt-1 is essential for preserving the avascular ambit of the cornea can rationally guide its use as a platform for angiogenic modulators, supports its use in treating neovascular diseases, and might provide insight into the immunological privilege of the cornea.

  11. Massive corneal edema treated with corneal cross-linking.

    Science.gov (United States)

    Laborante, A; Buzzonetti, L; Longo, C

    2012-01-01

    Massive corneal edema disrupts the fine architecture of corneal stroma that guarantees its transparency, causing opacities that seriously impair clear vision and are usually solved by corneal transplant. Corneal cross-linking, a treatment developed to halt keratoconus progression, results in a loss of water and a compaction of corneal stroma. It might therefore be useful to improve the pathologic edematous condition of some corneas, ameliorating visual acuity and allowing more time for a surgical procedure of keratoplasty. Six patients with visual impairing corneal edemas further to lens phacoemulsification, penetrating keratoplasty, or post-infective neovascularization were treated with corneal cross-linking alone, or in combination with amniotic membrane apposition with or without anti-angiogenic therapy. All patients partly resolved the edematous condition, improving both corneal transparency and visual acuity. Corneal cross-linking appears to be a useful method to treat massive corneal edemas, so that keratoplasty can be at least delayed, and need not to be an emergency treatment in these cases.

  12. Corneal Laceration

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    Full Text Available ... Corneal Laceration? Corneal Laceration Diagnosis Corneal Laceration Treatment What Is Corneal Laceration? Leer en Español: ¿Qué Es una Laceración de la Córnea? Written By: Daniel ...

  13. Corneal Ulcer

    Science.gov (United States)

    ... Español Eye Health / Eye Health A-Z Corneal Ulcer Sections What Is a Corneal Ulcer? Corneal Ulcer ... Diagnosis Corneal Ulcer Treatment What Is a Corneal Ulcer? Leer en Español: ¿Qué es una Úlcera de ...

  14. Globally Privileged Citizenship

    Science.gov (United States)

    Choules, Kathryn

    2006-01-01

    Educators interested in social change have been using an analysis of privilege in their gender and anti-racist work for some time. Through working with adult Australians in a community education programme on asylum seekers, the applicability of an analysis of privilege to the exclusionary discourses concerning asylum seekers and refugees became…

  15. Corneal Laceration

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    Full Text Available ... or apply pressure to eye avoid giving aspirin, ibuprofen or other non-steroidal, anti-inflammatory drugs. These ... lost sight from a corneal scar as a child. Now that I’m older, will a corneal ...

  16. Corneal Laceration

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    Full Text Available ... rub or apply pressure to eye avoid giving aspirin, ibuprofen or other non-steroidal, anti-inflammatory drugs. ... lost sight from a corneal scar as a child. Now that I’m older, will a corneal ...

  17. Corneal Laceration

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    Full Text Available ... Now that I’m older, will a corneal transplant help me? May 15, 2015 Why Do My ... May Have A Future Alternative to Full Corneal Transplantation Nov 29, 2016 Combating Eye Injuries from Air ...

  18. Corneal dystrophies

    Directory of Open Access Journals (Sweden)

    Klintworth Gordon K

    2009-02-01

    Full Text Available Abstract The term corneal dystrophy embraces a heterogenous group of bilateral genetically determined non-inflammatory corneal diseases that are restricted to the cornea. The designation is imprecise but remains in vogue because of its clinical value. Clinically, the corneal dystrophies can be divided into three groups based on the sole or predominant anatomical location of the abnormalities. Some affect primarily the corneal epithelium and its basement membrane or Bowman layer and the superficial corneal stroma (anterior corneal dystrophies, the corneal stroma (stromal corneal dystrophies, or Descemet membrane and the corneal endothelium (posterior corneal dystrophies. Most corneal dystrophies have no systemic manifestations and present with variable shaped corneal opacities in a clear or cloudy cornea and they affect visual acuity to different degrees. Corneal dystrophies may have a simple autosomal dominant, autosomal recessive or X-linked recessive Mendelian mode of inheritance. Different corneal dystrophies are caused by mutations in the CHST6, KRT3, KRT12, PIP5K3, SLC4A11, TACSTD2, TGFBI, and UBIAD1 genes. Knowledge about the responsible genetic mutations responsible for these disorders has led to a better understanding of their basic defect and to molecular tests for their precise diagnosis. Genes for other corneal dystrophies have been mapped to specific chromosomal loci, but have not yet been identified. As clinical manifestations widely vary with the different entities, corneal dystrophies should be suspected when corneal transparency is lost or corneal opacities occur spontaneously, particularly in both corneas, and especially in the presence of a positive family history or in the offspring of consanguineous parents. Main differential diagnoses include various causes of monoclonal gammopathy, lecithin-cholesterol-acyltransferase deficiency, Fabry disease, cystinosis, tyrosine transaminase deficiency, systemic lysosomal storage

  19. Angiogenic biomarkers in pregnancy

    DEFF Research Database (Denmark)

    Rasmussen, Lene G; Lykke, Jacob A; Staff, Anne C

    2015-01-01

    We review diagnostic and predictive roles of the angiogenic proteins placental growth factor, soluble fms-like tyrosine kinase 1, and soluble endoglin in preeclampsia, and their association with future cardiovascular disease, diabetes, and breast cancer. Specific patterns of these proteins repres...... are correlated to HbA1c and fasting glucose. Hence dysregulation in angiogenic proteins may link preeclampsia and cardiovascular diseases, targeting women who could in future benefit from prophylactic programs to possibly prevent, delay or reduce cardiovascular disease.......We review diagnostic and predictive roles of the angiogenic proteins placental growth factor, soluble fms-like tyrosine kinase 1, and soluble endoglin in preeclampsia, and their association with future cardiovascular disease, diabetes, and breast cancer. Specific patterns of these proteins...... represent preeclamptic prediction markers and combined with maternal and clinical characteristics, the predictive values increase. Women experiencing preeclampsia have increased risks of developing cardiovascular diseases and diabetes, and a decreased risk of breast cancer. High placental growth factor...

  20. Kant and therapeutic privilege.

    Science.gov (United States)

    Brown, Chris

    2008-08-01

    Given Kant's exceptionless moral prohibition on lying, one might suspect that he is committed to a similar prohibition on withholding diagnostic and prognostic information from patients. I confirm this suspicion by adapting arguments against therapeutic privilege from his arguments against lying. However, I show that all these arguments are importantly flawed and submit that they should be rejected. A more compelling Kantian take on informed consent and therapeutic privilege is achievable, I argue, by focusing on Kant's duty of beneficence, which requires us to aim at furthering others' ends. But I show that there are some cases in which furthering a patient's ends requires withholding material medical information from her. Although I concede that these cases are probably quite rare, I conclude that the best Kantian thinking agrees with that of therapeutic privilege's advocates.

  1. The classical pink-eyed dilution mutation affects angiogenic responsiveness.

    Science.gov (United States)

    Rogers, Michael S; Boyartchuk, Victor; Rohan, Richard M; Birsner, Amy E; Dietrich, William F; D'Amato, Robert J

    2012-01-01

    Angiogenesis is the process by which new blood vessels are formed from existing vessels. Mammalian populations, including humans and mice, harbor genetic variations that alter angiogenesis. Angiogenesis-regulating gene variants can result in increased susceptibility to multiple angiogenesis-dependent diseases in humans. Our efforts to dissect the complexity of the genetic diversity that regulates angiogenesis have used laboratory animals due to the availability of genome sequence for many species and the ability to perform high volume controlled breeding. Using the murine corneal micropocket assay, we have observed more than ten-fold difference in angiogenic responsiveness among various mouse strains. This degree of difference is observed with either bFGF or VEGF induced corneal neovascularization. Ongoing mapping studies have identified multiple loci that affect angiogenic responsiveness in several mouse models. In this study, we used F2 intercrosses between C57BL/6J and the 129 substrains 129P1/ReJ and 129P3/J, as well as the SJL/J strain, where we have identified new QTLs that affect angiogenic responsiveness. In the case of AngFq5, on chromosome 7, congenic animals were used to confirm the existence of this locus and subcongenic animals, combined with a haplotype-based mapping approach that identified the pink-eyed dilution mutation as a candidate polymorphism to explain AngFq5. The ability of mutations in the pink-eyed dilution gene to affect angiogenic response was demonstrated using the p-J allele at the same locus. Using this allele, we demonstrate that pink-eyed dilution mutations in Oca2 can affect both bFGF and VEGF-induced corneal angiogenesis.

  2. [Corneal biomechanics].

    Science.gov (United States)

    Torres, R M; Merayo-Lloves, J; Jaramillo, M A; Galvis, V

    2005-04-01

    To review the corneal biomechanic concepts and to analyse, clarify and understand their relevance in refractive surgery. A literature review has been done using different databases. Corneal biomechanic concepts are not new and are applied implicitly in numerous surgical procedures. Their origin is related to tonometry studies, but they gained in popularity when they were linked to the treatment of keratoconus, a pathology in which the mechanical properties of the cornea are altered. Factors determining corneal stability were thus defined. Corneal biomechanics have also been used following refractive surgery to study post-operative keratectasia and to improve ablation patterns, which ignores the corneal response. The new ablation systems need to include the biomechanical factors, which motivate research conducted in physical-mathematical models and in corneal wound healing, improving our knowledge about the corneal biomechanical response. The corneal biomechanic concepts have gained in popularity with the advent of refractive surgery, although they did exist previously. Their relevance is linked to improvements in the ablation systems used in an attempt to obtain more accurate and reliable results.

  3. Corneal Laceration

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    Full Text Available ... Answers How often and for how long should I use a hair dryer to treat my Fuchs’ dystrophy? May 06, 2017 I lost sight from a corneal scar as a child. Now that I’m older, will a corneal transplant help me? ...

  4. Corneal Laceration

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    Full Text Available ... Tips & Prevention News Ask an Ophthalmologist Patient Stories Español Eye Health / Eye Health A-Z Corneal Laceration ... Laceration Treatment What Is Corneal Laceration? Leer en Español: ¿Qué Es una Laceración de la Córnea? Written ...

  5. Corneal Laceration

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    Full Text Available ... Health Find an Ophthalmologist Academy Store Eye Health A-Z Symptoms Glasses & Contacts Tips & Prevention News Ask ... Ophthalmologist Patient Stories Español Eye Health / Eye Health A-Z Corneal Laceration Sections What Is Corneal Laceration? ...

  6. Corneal topography.

    Science.gov (United States)

    Seitz, B; Behrens, A; Langenbucher, A

    1997-08-01

    In the review period, limitations of individual Placido disk-based topography systems have been studied and new principles, such as raster photogrammetry, pancorneal slit topography, laser holographic interferometry, and confocal laser scanning topography, have been introduced for laboratory or clinical work. Both Fourier analysis and Zernike decomposition of topographic height data seem to be powerful new tools for cross-sectional analysis of complex topographic corneal images, such as after cataract surgery, penetrating keratoplasty, and refractive surgery, as well as for longitudinal studies of corneal changes, such as in schoolchildren. Subdividing into rational optical components may improve consistency and standardization of topography data from different systems. Topography-based flying-spot-mode excimer laser photoablation after Zernike decomposition of topography height data has been proposed for correction of irregular corneal astigmatism. Topography-based central power measurements are of increasing value for intraocular lens power calculation before cataract surgery in eyes with irregular corneal surfaces, such as in keratoconus or after refractive surgery procedures. Quantitative and qualitative classification of corneal topography maps after corneal transplantation following conventional mechanical and nonmechanical trephination or after refractive surgery may lead to a better understanding of impaired visual acuity despite a clear graft or despite significantly reduced ametropia or corneal astigmatism.

  7. Human tears reveal insights into corneal neovascularization.

    Science.gov (United States)

    Zakaria, Nadia; Van Grasdorff, Sigi; Wouters, Kristien; Rozema, Jos; Koppen, Carina; Lion, Eva; Cools, Nathalie; Berneman, Zwi; Tassignon, Marie-José

    2012-01-01

    Corneal neovascularization results from the encroachment of blood vessels from the surrounding conjunctiva onto the normally avascular cornea. The aim of this study is to identify factors in human tears that are involved in development and/or maintenance of corneal neovascularization in humans. This could allow development of diagnostic tools for monitoring corneal neovascularization and combination monoclonal antibody therapies for its treatment. In an observational case-control study we enrolled a total of 12 patients with corneal neovascularization and 10 healthy volunteers. Basal tears along with reflex tears from the inferior fornix, superior fornix and using a corneal bath were collected along with blood serum samples. From all patients, ocular surface photographs were taken. Concentrations of the pro-angiogenic cytokines interleukin (IL)-6, IL-8, Vascular Endothelial Growth Factor (VEGF), Monocyte Chemoattractant Protein 1 (MCP-1) and Fas Ligand (FasL) were determined in blood and tear samples using a flow cytometric multiplex assay. Our results show that the concentration of pro-angiogenic cytokines in human tears are significantly higher compared to their concentrations in serum, with highest levels found in basal tears. Interestingly, we could detect a significantly higher concentration of IL- 6, IL-8 and VEGF in localized corneal tears of patients with neovascularized corneas when compared to the control group. This is the first study of its kind demonstrating a significant difference of defined factors in tears from patients with neovascularized corneas as compared to healthy controls. These results provide the basis for future research using animal models to further substantiate the role of these cytokines in the establishment and maintenance of corneal neovascularization.

  8. Corneal Laceration

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    Full Text Available ... by something sharp flying into the eye. It can also be caused by something striking the eye ... If the corneal laceration is deep enough it can cause a full thickness laceration. This is when ...

  9. Corneal Laceration

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  10. Corneal Laceration

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    Full Text Available ... the blood and may increase bleeding after you have finished protecting the eye, see a physician immediately ... Jun 30, 2017 People with Advanced Keratoconus May Have A Future Alternative to Full Corneal Transplantation Nov ...

  11. Corneal Laceration

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    Full Text Available ... People with Advanced Keratoconus May Have A Future Alternative to Full Corneal Transplantation Nov 29, 2016 Combating Eye Injuries from ... of Service For Advertisers For Media Ophthalmology Job Center © American Academy of Ophthalmology 2017 ...

  12. Corneal Laceration

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    Full Text Available ... inflammatory drugs. These drugs thin the blood and may increase bleeding after you have finished protecting the ... a hair dryer to treat my Fuchs’ dystrophy? May 06, 2017 I lost sight from a corneal ...

  13. Corneal Laceration

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    Full Text Available ... By: Devin A Harrison MD Sep. 01, 2017 The cornea is the clear front window of the eye . A corneal laceration is a cut on the cornea. It is usually caused by something sharp ...

  14. Corneal Laceration

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    Full Text Available ... itself. A corneal laceration is a very serious injury and requires immediate medical attention to avoid severe ... Ask an Ophthalmologist Answers Did my traumatic brain injury cause early cataracts? Jan 21, 2018 Did I ...

  15. Corneal Laceration

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    Full Text Available ... caused by something striking the eye with significant force, like a metallic hand tool. A corneal laceration ... and preserving your vision. Privacy Policy Related Top 5 Eye Health Stories of 2017 Dec 21, 2017 ...

  16. Corneal Laceration

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    Full Text Available ... itself. A corneal laceration is a very serious injury and requires immediate medical attention to avoid severe ... Dangerous for Your Eyes Sep 20, 2017 Eye Injuries from Laundry Packets On the Rise Jun 30, ...

  17. Corneal collagens.

    Science.gov (United States)

    Robert, L; Legeais, J M; Robert, A M; Renard, G

    2001-05-01

    Cornea is a highly differentiated tissue rich in extracellular matrix (ECM) specifically distributed in space in order to insure its dual role--transparency and protection of inner eye-tissues. Corneal ECM is especially rich in collagens. Since the characterisation of a number of distinct collagen types it appeared that most of them are present in the cornea. Their synthesis follows a specific program of sequential expression of the different collagen types to be synthesised during the development and maturation of the cornea. The precise regulation of the diameter and orientation of fibers, and of the interfibrillar spaces is partially at least attributed to interactions between glycosaminoglycans and collagens. The 'program' of vectorial collagen synthesis and GAG-collagen interactions changes also with age and in several pathological conditions as corneal dystrophies and wound healing. The Maillard reaction, especially in diabetes, is one of these important factors involved in age-dependent modifications of corneal structure and function. Far from being inert, corneal collagens were shown to have relatively short half-lives. The biosynthesis of corneal collagens was studied also during wound healing. The refibrillation of wounded corneas does not follow the original 'program' of ECM-synthesis as shown by the comparative study of wound healing using biochemical and morphometric methods. This review recapitulates briefly previous and recent studies on corneal collagens in order to present to clinicians and scientists an overview of the state of the art of this important field at the intersection of eye research and matrix biology.

  18. Corneal Transplantation

    DEFF Research Database (Denmark)

    Hjortdal, Jesper Østergaard

    Corneal transplantation has been performed for more than 100 years. Until 15 years ago the state-of-the art type of transplantation was penetrating keratoplasty, but since the start of this millennium, newly designed surgical techniques have developed considerably. Today, the vast majority...... with less risk of rejection episodes. Besides covering updated chapters on penetrating keratoplasty, and anterior and posterior lamellar procedures, this textbook also gives a thorough overview of the history of corneal transplantation and a detailed presentation of the microstructural components....... Economic considerations on cost and benefi t of medical treatment and surgical procedures are today an integrated part of the health system in many countries, and a chapter covers these aspects of corneal transplantation. This textbook is aimed at presenting an updated review of the new techniques...

  19. Corneal Intelligence

    African Journals Online (AJOL)

    Murdoch3

    the damping effect of the tissue to an applied force) or corneal compliance being the major risk factor. Figure 1. The percentage of participants in the observation group who developed primary open-angle glaucoma (median follow-up, 72 months) ...

  20. Corneal ulcers

    African Journals Online (AJOL)

    visual acuity chart. • fluorescein strips. • topical anaesthetic eye drops. • direct ophthalmoscope. Examination. Assessing vision with a Snellen visual acuity chart gives a clue as to the extent of the problem (e.g. a corneal abrasion with good vision is unlikely to require specialist intervention). Each eye should be tested ...

  1. Corneal Intelligence

    African Journals Online (AJOL)

    Murdoch3

    Corneal Intelligence. Ian Murdoch. Institute of Ophthalmology, Bath Street, London. In 2002, the ocular hypertension treatment study (OHTS) published their results. This study had taken 1636 ocular hypertensives. 1, 2. (IOP 24-32mmHg) and randomized them to receive therapy or no therapy. The primary outcome of the ...

  2. Bilateral Alterations in Corneal Nerves, Dendritic Cells and Tear Cytokine Levels in Ocular Surface Disease

    Science.gov (United States)

    Yamaguchi, Takefumi; Hamrah, Pedram; Shimazaki, Jun

    2017-01-01

    This review summarizes recent literature regarding corneal imaging in human subjects using in vivo confocal microscopy and corneal immune cells, nerves, and tear cytokine levels in ocular surface diseases as well as corneal immune privilege. The significance of interactions between corneal immune cells and nerves in health, neurotrophic keratopathy, and infectious keratitis are discussed. Furthermore, bilateral alterations of immune cells and nerves in clinically unilateral corneal diseases and the link to changes of tear cytokines or neuropeptide levels in contralateral eyes are described. Recent studies reported increased density and morphologic changes of corneal dendritic cells in ocular surface disease that correlated with a decrease in sub-basal nerve corneal nerves, suggesting potential interactions between the immune and nervous systems in the cornea. Although the relevance of tear cytokines is poorly understood, tear cytokines might have an important role in the pathogenesis of ocular surface diseases. In humans and experimental animal models, alterations in immune cells, cytokines and immunomodulatory neuropeptide levels in contralateral eyes might mediate the incidence of bilateral infectious keratitis and loss of immune privilege of the cornea in bilateral corneal transplantation or neurotrophic keratopathy cases. The discovery of bilateral alterations of immune cells and nerves in ocular surface diseases is considered the missing link between the immune and nervous systems in the cornea, and demonstrates how studies of animal models and human patients aid our understanding of human corneal disease phenomena. PMID:27617877

  3. Corneal Gene Therapy: Basic Science and Translational Perspective

    Science.gov (United States)

    Mohan, Rajiv R.; Rodier, Jason T.; Sharma, Ajay

    2013-01-01

    Corneal blindness is the third leading cause of blindness worldwide. Gene therapy is an emerging technology for corneal blindness due to the accessibility and immune-privileged nature of the cornea, ease of vector administration and visual monitoring, and ability to perform frequent noninvasive corneal assessment. Vision restoration by gene therapy is contingent upon vector and mode of therapeutic gene introduction into targeted cells/tissues. Numerous efficacious vectors, delivery techniques, and approaches have evolved in last decade for developing gene-based interventions for corneal diseases. Maximizing the potential benefits of gene therapy requires efficient and sustained therapeutic gene expression in target cells, low toxicity, and a high safety profile. This review describes the basic science associated with many gene therapy vectors and the present progress of gene therapy carried out for various ocular surface disorders and diseases. PMID:23838017

  4. Cathepsin B-mediated CD18 shedding regulates leukocyte recruitment from angiogenic vessels.

    Science.gov (United States)

    Nakao, Shintaro; Zandi, Souska; Sun, Dawei; Hafezi-Moghadam, Ali

    2018-01-01

    Cathepsin B (CtsB) contributes to atherosclerosis and cancer progression by processing the extracellular matrix and promoting angiogenesis. Although CtsB was reported to promote and reduce angiogenesis, there is no mechanistic explanation that reconciles this apparent discrepancy. CtsB cleaves CD18 from the surface of immune cells, but its contribution to angiogenesis has not been studied. We developed an in vivo technique for visualization of immune cell transmigration from corneal vessels toward implanted cytokines. Wild-type (WT) leukocytes extravasated from limbal vessels, angiogenic stalks, and growing tip vessels and migrated toward the cytokines, indicating immune competence of angiogenic vessels. Compared to WT leukocytes, CtsB-/- leukocytes accumulated in a higher number in angiogenic vessels, but extravasated less toward the implanted cytokine. The accumulated CtsB-/- leukocytes in angiogenic vessels expressed more CD18. CD18-/- leukocytes extravasated later than WT leukocytes. However, once extravasated, CD18-/- leukocytes transmigrated more rapidly than their WT counterparts. These results suggest that, although CD18 facilitates efficient extravasation, outside of the vessel CD18 interaction with the extracellular matrix, it reduced transmigration velocity. Our results reveal an unexpected role for CtsB in leukocyte extravasation and transmigration, which advances our understanding of the complex contribution of CtsB to angiogenesis.-Nakao, S., Zandi, S., Sun, D., Hafezi-Moghadam, A. Cathepsin B-mediated CD18 shedding regulates leukocyte recruitment from angiogenic vessels. © FASEB.

  5. Corneal Transplantation in Children

    OpenAIRE

    Gabrić, N.; Dekaris, I.; Vojniković, B.; Karaman, Ž.; Mravičić, I.; Katušić, J.

    2001-01-01

    The main purpose of the study was to describe the surgical success rate and visual results of penetrating keratoplasty in children. This retrospective study included children that underwent corneal transplantation at the Department of Ophthalmology, General Hospital »Sveti Duh«, in the period 1994–1999. Patients’ age ranged from 6 to 16 years. Twenty-five corneal transplants were performed in 24 eyes. Corneal pathologies were corneal leucoma, congenital dystrophy, corneal combu...

  6. Influence of corneal astigmatism, corneal curvature and meridional differences on corneal hysteresis and corneal resistance factor.

    Science.gov (United States)

    Wong, Yin-zhi; Lam, Andrew K C

    2011-09-01

    This study investigated the influence of corneal astigmatism, corneal curvature and meridional differences on corneal hysteresis (CH) and the corneal resistance factor (CRF) in a group of normal Chinese persons. Ninety-five participants were recruited and data from the eye with higher corneal astigmatism were analysed. The anterior corneal curvature was measured by corneal topography. The Goldmann-correlated intraocular pressure (IOPg), corneal-compensated intraocular pressure (IOPcc), CH and CRF at different meridians (default horizontal position, 10°, 20° and 30° along the superotemporal and inferonasal meridians) were obtained from an ocular response analyser. The corneal powers at these specific meridians also were calculated. At the default position, the IOPg and CRF had weak correlations with corneal astigmatism, while the IOPcc and CH were not significantly correlated with corneal astigmatism. Both the IOPg and IOPcc were measured significantly higher at the default position. The CH and CRF were lower at the default position but the difference in the CRF from obliquity could not reach statistical significance. The CH was not significantly correlated with the corneal power at all meridians. The CRF correlated with the corneal power only at 30° superotemporal. Corneal astigmatism and head tilt did not have much effect on the measurement of CH and the CRF, both of which were lowest along the horizontal meridian. Clinically, the difference was small. The influence of corneal power on CH and the CRF was minimal. © 2011 The Authors. Clinical and Experimental Optometry © 2011 Optometrists Association Australia.

  7. [Immunological aspects of corneal graft rejection and own experience in immunosuppressive therapy in high risk patients].

    Science.gov (United States)

    Kamińska, Anna; Szaflik, Jerzy; Minkiewicz-Timler, Grazyna; Sybilska, Małgorzata; Pawluczyk-Dyjecińska, Martyna; Smolarek, Monika

    2004-01-01

    The aim of the study was to present factors responsible for immune privilege of corneal graft, pathogenesis of immunological corneal graft rejection, and the influence of immunosuppressive therapy on keeping clarity of corneal graft. We also present retrospective evaluation of prophylactic immunosuppressive therapy in high-risk patients and in cases of graft rejection, in group of patients after corneal transplantation performed in Department of Ophthalmology in years 2001-2003. 349 cases of penetrating keratoplasty, lamellar or penetrating with limbal transplantation were analyzed. Condition requiring keratoplasty, surgical procedures, profile of immunosuppressive therapy, number of recurrences of corneal graft rejection and changes of visual acuity were evaluated. Immunosuppressive therapy with oral corticosteroids and systemic Cyclosporine allow to keep clarity of corneal graft and useful visual acuity in 60% cases of high-risk patients.

  8. Designing with Bias and Privilege?

    DEFF Research Database (Denmark)

    Søndergaard, Marie Louise Juul; Hansen, Lone Koefoed

    2017-01-01

    to critically intervene into agency and power structures, and we analyse how the designer’s position impacts this intervention. With this case, we demonstrate how a simple argument – that what you design is always influenced by your (lack of) privilege – becomes complex when understood in the concrete design...

  9. Graphene Oxides Show Angiogenic Properties.

    Science.gov (United States)

    Mukherjee, Sudip; Sriram, Pavithra; Barui, Ayan Kumar; Nethi, Susheel Kumar; Veeriah, Vimal; Chatterjee, Suvro; Suresh, Kattimuttathu Ittara; Patra, Chitta Ranjan

    2015-08-05

    Angiogenesis, a process resulting in the formation of new capillaries from the pre-existing vasculature plays vital role for the development of therapeutic approaches for cancer, atherosclerosis, wound healing, and cardiovascular diseases. In this report, the synthesis, characterization, and angiogenic properties of graphene oxide (GO) and reduced graphene oxide (rGO) have been demonstrated, observed through several in vitro and in vivo angiogenesis assays. The results here demonstrate that the intracellular formation of reactive oxygen species and reactive nitrogen species as well as activation of phospho-eNOS and phospho-Akt might be the plausible mechanisms for GO and rGO induced angiogenesis. The results altogether suggest the possibilities for the development of alternative angiogenic therapeutic approach for the treatment of cardiovascular related diseases where angiogenesis plays a significant role. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Unveiling Privilege to Broaden Participation

    Science.gov (United States)

    Scherr, Rachel E.; Robertson, Amy D.

    2017-10-01

    The underrepresentation of women and people of color in physics has been attributed to a wide variety of factors ranging from society-wide conditions such as income inequality and sparse role models, to daily interpersonal interactions that disadvantage or discourage women and people of color from pursuing physics. These factors may be seen as manifestations of White and/or male privilege: social, economic, educational, or political advantages that are made available to Whites and males on the basis of their social identity. White male privilege pervades the discipline of physics as well as the classrooms in which physics is taught and learned. For example, physics is portrayed in textbooks as the product of individual great men, independent of all social or political contexts, rather than as being shaped by the culture of the European Enlightenment (among other cultures) or the conditions during specific international conflicts.

  11. Targeted corneal transplantation.

    Science.gov (United States)

    Jhanji, Vishal; Mehta, Jod S; Sharma, Namrata; Sharma, Bhavana; Vajpayee, Rasik B

    2012-07-01

    Corneal transplantation surgery has moved from an era of conventional penetrating keratoplasty to selective replacement of the diseased corneal layer with complementary healthy donor corneal tissue. Anterior lamellar transplantation surgeries do not involve replacement of corneal endothelium, consequently eliminating the occurrence of endothelial rejection. Similarly, in diseases affecting the corneal endothelium, selective replacement with a lamellar lenticule bearing healthy endothelium provides better outcomes in terms of ocular surface, lesser astigmatism and quick visual recovery. In addition to the advantages of enhanced surgical outcomes, targeted corneal transplantation allows the use of one donor cornea for more than one recipient, thereby offering a viable solution to the problem of paucity of donor corneas. Evolving techniques of corneal transplantation have enabled better utilization of donor corneal tissue. Anterior lamellar as well as endothelial keratoplasty surgeries have become first-choice surgeries in appropriately selected cases. This review briefly discusses some of these novel surgical techniques. A better understanding of targeted corneal transplantation would lead to adaptation of the concept of component corneal surgery. This would further enable the corneal surgeons to circumvent the problem of donor corneal shortage especially in the developing world.

  12. Equine corneal stromal abscesses

    DEFF Research Database (Denmark)

    Henriksen, M. D. L.; Andersen, P. H.; Plummer, C. E.

    2013-01-01

    The last 30 years have seen many changes in the understanding of the pathogenesis and treatment of equine corneal stromal abscesses (SAs). Stromal abscesses were previously considered an eye problem related to corneal bacterial infection, equine recurrent uveitis, corneal microtrauma and corneal...... foreign bodies in horses. They were more commonly diagnosed in horses living in subtropical climatic areas of the world. Therapeutic recommendations to treat equine SAs were historically nearly always a medical approach directed at bacteria and the often associated severe iridocyclitis. Today...... the pathogenesis of most equine SAs appears to be more often related to fungal inoculation of the anterior corneal stroma followed by posterior migration of the fungi deeper into the corneal stroma. There is also now an increased incidence of diagnosis of corneal SAs in horses living in more temperate climates...

  13. Corneal transplantation in children.

    Science.gov (United States)

    Gabrić, N; Dekaris, I; Vojniković, B; Karaman, Z; Mravicić, I; Katusić, J

    2001-01-01

    The main purpose of the study was to describe the surgical success rate and visual results of penetrating keratoplasty in children. This retrospective study included children that underwent corneal transplantation at the Department of Ophthalmology, General Hospital "Sveti Duh", in the period 1994-1999. Patients' age ranged from 6 to 16 years. Twenty-five corneal transplants were performed in 24 eyes. Corneal pathologies were corneal leucoma, congenital dystrophy, corneal combustion, corneal scar after perforating injury, keratoconus, corneal melting, hematocornea and rekeratoplasty. The follow-up period was at least 6 months. The rate of graft survival was 1 year in 75% of eyes with congenital dystrophy and keratoconus. Hematocornea and rekeratoplasty ended with graft failure. Postoperative visual acuity improvement was recorded in 14 out of 25 eyes. Penetrating keratoplasty in children showed very good surgical success. The final visual outcome was affected by irreversible amblyopia.

  14. Ways to Improve (Visual) Outcome in Corneal Transplantation, Corneal Pathology

    NARCIS (Netherlands)

    M.C. Bartels (Marjolijn)

    2005-01-01

    textabstractThe normally transparent cornea can lose its ability to refract light regularly from various conditions. Among these conditions are corneal opacities and corneal diseases leading to a distortion of the corneal contour. Vision might be restored by a corneal transplantation. Corneal

  15. Inhibitory effect of polysulfated heparin endostatin onalkali burn induced corneal neovascularization in rabbits

    Directory of Open Access Journals (Sweden)

    Zhao-Na Li

    2015-04-01

    Full Text Available AIM: To investigate anti-angiogenic effects of polysulfated heparin endostatin (PSH-ES on alkali burn induced corneal neovascularization (NV in rabbits. METHODS: An alkali burn was made on rabbit corneas to induce corneal NV in the right eye of 24 rabbits. One day after burn creation, a 0.2 mL subconjunctival injection of 50 μg/mL PSH-ES, 50 μg/mL recombinant endostatin (ES, or normal saline was administered every other day for a total of 14d (7 injections. Histology and immunohistochemisty were used to examine corneas. Corneal NV growth was evaluated as microvessel quantity and corneal vascular endothelial growth factor (VEGF expression was measured by immunohistochemical assay. RESULTS: Subconjunctival injection of ES and PSH-ES resulted in significant corneal NV suppression, but PSH-ES had a more powerful anti-angiogenic effect than ES. Mean VEGF concentration in PSH-ES treated corneas was significantly lower than in ES treated and saline treated corneas. Histological examination showed that corneas treated with either PSH-ES or ES had significantly fewer microvessels than eyes treated with saline. Additionally corneas treated with PSH-ES had significantly fewer microvessels than corneas treated with ES. CONCLUSION: Both PSH-ES and recombinant ES effectively inhibit corneal NV induced by alkali burn. However, PSH-ES is a more powerful anti-angiogenic agent than ES. This research has the potential to provide a new treatment option for preventing and treating corneal NV.

  16. 14 CFR 61.167 - Privileges.

    Science.gov (United States)

    2010-01-01

    ... debriefings, an airline transport pilot may not instruct in aircraft, flight simulators, and flight training... CERTIFICATION: PILOTS, FLIGHT INSTRUCTORS, AND GROUND INSTRUCTORS Airline Transport Pilots § 61.167 Privileges. (a) A person who holds an airline transport pilot certificate is entitled to the same privileges as a...

  17. Vanishing corneal vessels

    Science.gov (United States)

    Nicholson, Luke; Chana, Rupinder

    2013-01-01

    We wish to highlight the importance of acknowledging the accompanying effects of topical phenylephrine drops on the eye other than its intended mydriasis. We reported a case of a 92-year-old woman with a corneal graft who was noted to have superficial corneal vascularisation which was not documented previously. After the instillation of topical tropicamide 1% and phenylephrine 2.5%, for funduscopy, the corneal vascularisation was not visible. When reassessed on another visit, tropicamide had no effect on the vessels and only phenylephrine did. We wish to highlight that when reviewing patients in cornea clinics, instilling phenylephrine prior to being seen may mask important corneal vascularisation. PMID:24121816

  18. Adipose-derived mesenchymal stem cell administration does not improve corneal graft survival outcome.

    Directory of Open Access Journals (Sweden)

    Sherezade Fuentes-Julián

    Full Text Available The effect of local and systemic injections of mesenchymal stem cells derived from adipose tissue (AD-MSC into rabbit models of corneal allograft rejection with either normal-risk or high-risk vascularized corneal beds was investigated. The models we present in this study are more similar to human corneal transplants than previously reported murine models. Our aim was to prevent transplant rejection and increase the length of graft survival. In the normal-risk transplant model, in contrast to our expectations, the injection of AD-MSC into the graft junction during surgery resulted in the induction of increased signs of inflammation such as corneal edema with increased thickness, and a higher level of infiltration of leukocytes. This process led to a lower survival of the graft compared with the sham-treated corneal transplants. In the high-risk transplant model, in which immune ocular privilege was undermined by the induction of neovascularization prior to graft surgery, we found the use of systemic rabbit AD-MSCs prior to surgery, during surgery, and at various time points after surgery resulted in a shorter survival of the graft compared with the non-treated corneal grafts. Based on our results, local or systemic treatment with AD-MSCs to prevent corneal rejection in rabbit corneal models at normal or high risk of rejection does not increase survival but rather can increase inflammation and neovascularization and break the innate ocular immune privilege. This result can be partially explained by the immunomarkers, lack of immunosuppressive ability and immunophenotypical secretion molecules characterization of AD-MSC used in this study. Parameters including the risk of rejection, the inflammatory/vascularization environment, the cell source, the time of injection, the immunosuppression, the number of cells, and the mode of delivery must be established before translating the possible benefits of the use of MSCs in corneal transplants to clinical

  19. Characterization of Corneal Indentation Hysteresis.

    Science.gov (United States)

    Ko, Match W L; Dongming Wei; Leung, Christopher K S

    2015-01-01

    Corneal indentation is adapted for the design and development of a characterization method for corneal hysteresis behavior - Corneal Indentation Hysteresis (CIH). Fourteen porcine eyes were tested using the corneal indentation method. The CIH measured in enucleated porcine eyes showed indentation rate and intraocular pressure (IOP) dependences. The CIH increased with indentation rate at lower IOP ( 25 mmHg). The CIH was linear proportional to the IOP within an individual eye. The CIH was positively correlated with the IOP, corneal in-plane tensile stress and corneal tangent modulus (E). A new method based on corneal indentation for the measurement of Corneal Indentation Hysteresis in vivo is developed. To our knowledge, this is the first study to introduce the corneal indentation hysteresis and correlate the corneal indentation hysteresis and corneal tangent modulus.

  20. corneal pyogenic granuloma

    African Journals Online (AJOL)

    GB

    2012-09-14

    Sep 14, 2012 ... Figure 3: A child with pyogenic cornea granuloma intra operatively. After excision of the mass, central corneal stromal defect developed. The patient was followed up for more than a month with topical antibiotic and cycloplegic. Subsequently, the defect healed and leucoma corneal opacity (figure.

  1. Corneal biomechanics - a review.

    Science.gov (United States)

    Kling, Sabine; Hafezi, Farhad

    2017-05-01

    In recent years, the interest in corneal biomechanics has strongly increased. The material properties of the cornea determine its shape and therefore play an important role in corneal ectasia and related pathologies. This review addresses the molecular origin of biomechanical properties, models for their description, methods for their characterisation, techniques for their modification, and computational simulation approaches. Recent research has focused on developing non-contact techniques to measure the biomechanical properties in vivo, on determining structural and molecular abnormalities in pathological corneas, on developing and optimising techniques to reinforce the corneal tissue and on the computational simulation of surgical interventions. A better understanding of corneal biomechanics will help to improve current refractive surgeries, allow an earlier diagnosis of ectatic disorders and a better quantification of treatments aiming at reinforcing the corneal tissue. © 2017 The Authors Ophthalmic & Physiological Optics © 2017 The College of Optometrists.

  2. Is human fracture hematoma inherently angiogenic?

    LENUS (Irish Health Repository)

    Street, J

    2012-02-03

    This study attempts to explain the cellular events characterizing the changes seen in the medullary callus adjacent to the interfragmentary hematoma during the early stages of fracture healing. It also shows that human fracture hematoma contains the angiogenic cytokine vascular endothelial growth factor and has the inherent capability to induce angiogenesis and thus promote revascularization during bone repair. Patients undergoing emergency surgery for isolated bony injury were studied. Raised circulating levels of vascular endothelial growth factor were seen in all injured patients, whereas the fracture hematoma contained significantly higher levels of vascular endothelial growth factor than did plasma from these injured patients. However, incubation of endothelial cells in fracture hematoma supernatant significantly inhibited the in vitro angiogenic parameters of endothelial cell proliferation and microtubule formation. These phenomena are dependent on a local biochemical milieu that does not support cytokinesis. The hematoma potassium concentration is cytotoxic to endothelial cells and osteoblasts. Subcutaneous transplantation of the fracture hematoma into a murine wound model resulted in new blood vessel formation after hematoma resorption. This angiogenic effect is mediated by the significant concentrations of vascular endothelial growth factor found in the hematoma. This study identifies an angiogenic cytokine involved in human fracture healing and shows that fracture hematoma is inherently angiogenic. The differences between the in vitro and in vivo findings may explain the phenomenon of interfragmentary hematoma organization and resorption that precedes fracture revascularization.

  3. CORNEAL BLINDNESS AND XENOTRANSPLANTATION

    Science.gov (United States)

    Lamm, Vladimir; Hara, Hidetaka; Mammen, Alex; Dhaliwal, Deepinder; Cooper, David K.C.

    2014-01-01

    Approximately 39 million people are blind worldwide, with an estimated 285 million visually impaired. The developing world shoulders 90% of the world’s blindness, with 80% of causative diseases being preventable or treatable. Blindness has a major detrimental impact on the patient, community, and healthcare spending. Corneal diseases are significant causes of blindness, affecting at least 4 million people worldwide. The prevalence of corneal disease varies among parts of the world. Trachoma, for instance, is the second leading cause of blindness in Africa, after cataracts, but is rarely found today in developed nations. When preventive strategies have failed, corneal transplantation is the most effective treatment for advanced corneal disease. The major surgical techniques for corneal transplantation include penetrating keratoplasty (PK), anterior lamellar keratoplasty (ALK), and endothelial keratoplasty (EK). Indications for corneal transplantation vary among countries, with Fuchs’ dystrophy being the leading indication in the U.S. and keratoconus in Australia. With the exception of the US, where EK will soon overtake PK as the most common surgical procedure, PK is the overwhelming procedure of choice. Success using corneal grafts in developing nations, such as Nepal, demonstrates the feasibility of corneal transplantation on a global scale. The number of suitable corneas from deceased human donors that becomes available will never be sufficient, and so research into various alternatives, e.g., stem cells, amniotic membrane transplantation, synthetic and biosynthetic corneas, and xenotransplantation, is progressing. While each of these has potential, we suggest that xenotransplantation holds the greatest potential for a corneal replacement. With the increasing availability of genetically-engineered pigs, pig corneas may alleviate the global shortage of corneas in the near future. PMID:25268248

  4. Comparison of anti-angiogenic properties of pristine carbon nanoparticles

    DEFF Research Database (Denmark)

    Wierzbicki, Mateusz; Sawosz, Ewa; Grodzik, Marta

    2013-01-01

    showed the greatest anti-angiogenic properties. Interestingly, fullerene exhibited the opposite effect, increasing blood vessel development, while graphite nanoparticles and graphene had no effect. Subsequently, protein levels of pro-angiogenic growth factor receptors were analysed, showing that diamond...

  5. Corneal transplant - slideshow

    Science.gov (United States)

    ... ency/presentations/100082.htm Corneal transplant - series—Normal anatomy To use the sharing features on this page, ... Bethesda, MD 20894 U.S. Department of Health and Human Services National Institutes of Health Page last updated: ...

  6. Pedagogy of the Privileged: Review of Deconstructing Privilege: Teaching and Learning as Allies in the Classroom.

    Science.gov (United States)

    Toporek, Rebecca L

    2014-08-11

    As scholarship and research in multicultural psychology evolves to a multilayered and complex discipline, increased attention to the role of larger structural forces of privilege has come to the forefront. Intersectionality of sociopolitical identities and the role those with privilege have in confronting oppression becomes a critical component of multicultural education. The edited volume, Deconstructing Privilege: Teaching and Learning as Allies in the Classroom (Case, 2013) provides concrete guidance and examples for educators seeking to enhance their approach to teaching privilege as a necessary mirror of oppression. This review highlights strengths of the book for educators in psychology and suggests recommendations for more complex discussion of the integration of privilege within the framework of structural oppression. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

  7. Identification of a potent endothelium-derived angiogenic factor

    DEFF Research Database (Denmark)

    Jankowski, Vera; Tölle, Markus; Tran, Thi Nguyet Anh

    2013-01-01

    The secretion of angiogenic factors by vascular endothelial cells is one of the key mechanisms of angiogenesis. Here we report on the isolation of a new potent angiogenic factor, diuridine tetraphosphate (Up4U) from the secretome of human endothelial cells. The angiogenic effect of the endothelia...

  8. Angiogenic Factors and Renal Disease in Pregnancy

    Directory of Open Access Journals (Sweden)

    Julie S. Rhee

    2011-01-01

    Full Text Available Background. Preeclampsia is difficult to diagnose in patients with underlying renal disease and proteinuria. Prior studies show that there is an angiogenic factor imbalance with elevated levels of antiangiogenic proteins soluble fms-like tyrosine kinase 1 (sFlt1 and soluble endoglin (sEng and reduced levels of the proangiogenic protein, placental growth factor (PlGF in women with preeclampsia. These angiogenic biomarkers may be useful in distinguishing preeclampsia from other conditions of pregnancy, which may present with overlapping clinical characteristics. Cases. Case 1: A multiparous woman at 18 weeks gestation with nephrotic syndrome presented with hypertensive emergency and worsening renal insufficiency. She underwent induction of labor for severe preeclampsia. Her sFlt1 and sEng levels were at the 97 percentile while her PlGF level was undetectable (less than the 1st percentile. Case 2: A nulliparous woman with lupus nephritis at 22 weeks gestation presented with fetal demise and heart failure. Three weeks previously, the patient had developed thrombocytopenia and hypertensive urgency. She underwent dilation and evacuation. Her angiogenic profile was consistent with severe preeclampsia. Conclusion. Angiogenic factors may provide evidence to support a diagnosis of preeclampsia in patients with preexisting renal disease and proteinuria, conditions in which the classical definition of hypertension and proteinuria cannot be used.

  9. Distrofia corneal de Schnyder

    Directory of Open Access Journals (Sweden)

    Michel Guerra Almaguer

    Full Text Available La principal entidad hereditaria con depósitos de lípidos en el estroma corneal es la distrofia cristalina central, conocida como distrofia de Schnyder, quien la describió en Suiza en 1927. Se caracteriza por depósitos blanco-amarillentos en el estroma corneal central y superficial. Se presenta un paciente de 28 años, del sexo masculino y piel negra, con antecedente de salud anterior. Acudió a consulta y refirió una disminución de la visión y cambio de coloración progresiva de ambos ojos, de años de evolución. En la exploración oftalmológica de ambos ojos se apreciaron lesiones blanquecinas anulares a nivel del estroma corneal, con ligera turbidez corneal central. Los estudios refractivos realizados constataron un astigmatismo hipermetrópico simple. El resto del examen oftalmológico fue negativo. Para el diagnóstico de certeza se empleó el microscopio confocal. Se concluye que el caso presenta una distrofia corneal estromal de tipo cristalina, de Schnyder.

  10. Research progress of corneal transplantation

    OpenAIRE

    Bing-Jie Zhang; Heng Sun; Yuan-Ping Zhang; Lin-Kun Ma

    2015-01-01

    Corneal transplantation is an ophthalmology treatment technique for corneal disease to help restore vision or control the development of corneal diseases by removing a scarred or damaged host cornea and replacing it with a clear and healthy donor cornea. Traditional corneal transplantation includes penetrating keratoplasty and lamellar keratoplasty. In recent ten years, deep lamellar keratoplasty and endothelial keratoplasty have gradually developed. At present, the development of keratoprost...

  11. Effects of nicotine on corneal wound healing following acute alkali burn.

    Science.gov (United States)

    Kim, Jong Won; Lim, Chae Woong; Kim, Bumseok

    2017-01-01

    Epidemiological studies have indicated that smoking is a pivotal risk factor for the progression of several chronic diseases. Nicotine, the addictive component of cigarettes, has powerful pathophysiological properties in the body. Although the effects of cigarette smoking on corneal re-epithelialization have been studied, the effects of nicotine on corneal wound healing-related neovascularization and fibrosis have not been fully demonstrated. The aim of this study was to evaluate the effects of chronic administration of nicotine on corneal wound healing following acute insult induced by an alkali burn. BALB/C female mice randomly received either vehicle (2% saccharin) or nicotine (100 or 200 μg/ml in 2% saccharin) in drinking water ad libitum. After 1 week, animals were re-randomized and the experimental group was subjected to a corneal alkali burn, and then nicotine was administered until day 14 after the alkali burn. A corneal alkali burn model was generated by placing a piece of 2 mm-diameter filter paper soaked in 1N NaOH on the right eye. Histopathological analysis and the expression level of the pro-angiogenic genes vascular endothelial growth factor (VEGF) and matrix metalloproteinase-9 (MMP9) revealed that chronic nicotine administration enhanced alkali burn-induced corneal neovascularization. Furthermore, the mRNA expression of the pro-fibrogenic factors α-smooth muscle actin (αSMA), transforming growth factor-β (TGF-β), and collagen α1 (Col1) was enhanced in the high-concentration nicotine-treated group compared with the vehicle group after corneal injury. Immunohistochemical analysis also showed that the αSMA-positive area was increased in chronic nicotine-treated mice after corneal alkali burn. An in vitro assay found that expression of the α3, α7, and β1 nicotinic acetylcholine receptor (nAChR) subunits was significantly increased by chemical injury in human corneal fibroblast cells. Moreover, alkali-induced fibrogenic gene expression and

  12. Privileged Communication in School Counseling: Status Update.

    Science.gov (United States)

    Sheeley, Vernon Lee; Herlihy, Barbara

    1987-01-01

    Reports findings from a 1985 study which contacted legislative research commission council, state librarian, and Department of Education officials in all 50 states, the District of Columbia, and the six United States trust territories to update the status of privileged communication statutes pertaining to school counselors and students they…

  13. Adult Education: Politics, Rights and Privilege.

    Science.gov (United States)

    Mason, Robb; Randell, Shirley

    1995-01-01

    In the 1990s, the idea of adult education as a right or privilege has yielded to the notion of education as a private consumer good. This concept makes it difficult for liberal adult education to achieve such goals as liberation, personal and social enlightenment, and social harmony and integration. (SK)

  14. Privileged Emotion Managers: The Case of Actors

    Science.gov (United States)

    Orzechowicz, David

    2008-01-01

    Theatre provides a unique set of conditions for the management of emotions. Drawing on participant observation from one repertory theater, three university productions, and interviews with stage actors, directors, and acting instructors, I conceptualize actors as privileged emotion managers. Actors access structural resources that enable their…

  15. Privileged Communication: Legal Status & Ethical Issues.

    Science.gov (United States)

    Herlihy, Barbara; Sheeley, Vernon Lee

    This report presents findings of research regarding extant privileged communication statutes in the 50 states for selected helping professionals: psychologists, social workers, marriage and family therapists/counselors, school counselors, and licensed professional counselors. Data are reported regarding the extent to which each of these…

  16. 46 CFR 310.64 - Privileges.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false Privileges. 310.64 Section 310.64 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION TRAINING MERCHANT MARINE TRAINING Admission and Training of... regulations. (e) Relatives and friends of midshipmen may visit at the Academy during such ours as the...

  17. 78 FR 37787 - Order Denying Export Privileges

    Science.gov (United States)

    2013-06-24

    ..., Inmate Number 96976- 279, FCI Big Spring, Federal Corrections Institution, 1900 Simler Avenue, Big Spring... from the date of the conviction. 15 CFR 766.25(d); see also 50 U.S.C. app. 2410(h). In addition...'s export privileges under the Regulations for a period of 10 years from the date of Pavon's...

  18. Encountering My Privilege (and Others' Oppression)

    Science.gov (United States)

    Kirby, Erika L.

    2016-01-01

    Courses: Communication and Diversity, Intercultural Communication, Gender Communication. Objectives: After completing this semester-long activity, students should be able to (1) articulate a systems-of-oppression (privilege??oppression) approach to thinking about difference; (2) confront and "interact differently" with one social…

  19. Airbag induced corneal ectasia.

    Science.gov (United States)

    Mearza, Ali A; Koufaki, Fedra N; Aslanides, Ioannis M

    2008-02-01

    To report a case of airbag induced corneal ectasia. Case report. A patient 3 years post-LASIK developed bilateral corneal ectasia worse in the right eye following airbag deployment in a road traffic accident. At last follow up, best corrected vision was 20/40 with -4.00/-4.00 x 25 in the right eye and 20/25 with -1.25/-0.50 x 135 in the left eye. This is a rare presentation of trauma induced ectasia in a patient post-LASIK. It is possible that reduction in biomechanical integrity of the cornea from prior refractive surgery contributed to this presentation.

  20. Research progress of corneal transplantation

    Directory of Open Access Journals (Sweden)

    Bing-Jie Zhang

    2015-06-01

    Full Text Available Corneal transplantation is an ophthalmology treatment technique for corneal disease to help restore vision or control the development of corneal diseases by removing a scarred or damaged host cornea and replacing it with a clear and healthy donor cornea. Traditional corneal transplantation includes penetrating keratoplasty and lamellar keratoplasty. In recent ten years, deep lamellar keratoplasty and endothelial keratoplasty have gradually developed. At present, the development of keratoprosthesis provides a new choice for the patients no suitable for traditional. The review describes current surgical techniques in the field of corneal transplantation about indications, postoperative complications, and so on.

  1. A Chaplain’s Guide to Privileged Communications

    Science.gov (United States)

    2001-04-01

    legal, and professional ) an ethical principle is developed, which is then applied to specific situation involving privileged communication . This...legal, and professional ) an ethical principle is developed, which is then applied to specific situation involving privileged communication . This work...Privileged Communication Under Law – The Chaplain as Counselor 94 The Professional Relationship – The Chaplain as Confidante

  2. 19 CFR 360.108 - Loss of electronic licensing privileges.

    Science.gov (United States)

    2010-04-01

    ... MONITORING AND ANALYSIS SYSTEM § 360.108 Loss of electronic licensing privileges. Should Commerce determine... system, Commerce may revoke its electronic licensing privileges without prior notice. The filer will then... 19 Customs Duties 3 2010-04-01 2010-04-01 false Loss of electronic licensing privileges. 360.108...

  3. What Business Students Should Know about Attorney-Client Privilege

    Science.gov (United States)

    Draba, Robert; Marshall, Brent

    2012-01-01

    The case law on attorney-client privilege is extensive and can be somewhat complex. Over seven hundred articles in Westlaw, for example, have the phrase "attorney-client privilege" in the title; in the last three years alone, there have been over 3700 federal cases in which the phrase "attorney-client privilege" appears at least once. However,…

  4. 38 CFR 17.501 - Confidential and privileged documents.

    Science.gov (United States)

    2010-07-01

    ... privileged documents. 17.501 Section 17.501 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS... privileged documents. (a) Documents and parts of documents are considered confidential and privileged if they... of special incidents (VA Form 10-2633 or similar forms) and follow-up documents unless developed...

  5. Educational Interventions to Raise Awareness of White Privilege

    Science.gov (United States)

    Case, Kim A.; Rios, Desdamona

    2017-01-01

    Diversity courses in higher education often seek to deepen understanding of the systematic advantages associated with dominant group membership, such as white privilege. Most pedagogical studies of privilege awareness examine the impact of full-length diversity courses on white privilege awareness (Case, 2007; Kernahan & Davis, 2009; Lawrence…

  6. Privileged Communication in the School Psychologist-Client Relationship

    Science.gov (United States)

    Jacob, Susan; Powers, Katie E.

    2009-01-01

    In the years since the 1996 Supreme Court "Jaffee v. Redmond" decision, many states broadened the scope of their laws governing privilege to include non-doctoral school psychologists. This article addresses the meaning of the term "privileged communication" and identifies common exceptions to privilege. Findings from a computerized search of the…

  7. The concept of privilege: a critical appraisal | Monahan | South ...

    African Journals Online (AJOL)

    In this essay, I examine the use of the concept of privilege within the critical theoretical discourse on oppression and liberation (with a particular focus on white privilege and antiracism in the USA). In order to fulfill the rhetorical aims of liberation, concepts for privilege must meet what I term the 'boundary condition', which ...

  8. Anti-angiogenic therapy: concept to clinic.

    Science.gov (United States)

    Young, Robin J; Reed, Malcolm W R

    2012-02-01

    It has been 40 years since Folkman hypothesized the use of anti-angiogenic therapy as a strategy in the treatment of cancer. Since then, vascular endothelial growth factor (VEGF) has been identified as the most potent cytokine to induce angiogenesis and drugs targeting VEGF, principally the humanized monoclonal antibody bevacizumab and the tyrosine kinase inhibitors sunitinib and sorafenib, have proven therapeutic benefit. The initial high expectations of tumor vascular targeting agents, however, have yet to be fulfilled. In unselected patient populations, the benefits of these agents is often marginal, they cause harmful side effects, and drug resistance is quickly established. Biomarkers to identify patients suitable for anti-angiogenic therapy will be key to the future development of these drugs. © 2012 John Wiley & Sons Ltd.

  9. Angiogenesis and Anti-Angiogenic Treatments

    Directory of Open Access Journals (Sweden)

    Ersin Demirer

    2013-10-01

    Full Text Available Blood vessels in our body is developed by vasculogenesis and angiogenesis. There have been new advances in molecular pathology and tumor biology areas in recent years. Angiogenesis is modulated by the balance between angiogenic and anti-angiogenic factors. Angiogenesis plays a key role in tumor growth. Drugs inhibiting angiogenesis have been in use in various malign or non-malign diseases. Inhibition of angiogenesis in malign diseases is a very attractive subject in medicine and studies are going on about long term affects and toxicities. Inhibition of angiogenesis is not an only treatment choice alone. It is a supplemental treatment option applied with conventional chemotherapy, radiotherapy, surgery, immunotherapy and hormonal therapy. It has been used in colorectal carcinoma, renal cell carcinoma, non-small cell lung cancer, glioblastoma, heoatocellular carcinoma, pancreatic neuroendocrine tumor, tyroid medullary cancer.

  10. Tumor angiogenic factor and human skin tumors.

    Science.gov (United States)

    Wolf, J E; Hubler, W R

    1975-03-01

    A transparent acrylic hamster cheek-pouch chamber was used to investigate the elaboration of a tumor angiogenic factor (TAF) by human cutaneous neoplasms; direct tumor implantations, transfilter diffusion, and soluble tumor extracts were used in the study. A diffusible and filterable TAF was extracted from cutaneous tumors and produced distinctive patterns of sequential vasodilatation, tortuosity, and neovascular proliferation in the cheek-pouch membrane. Malignant human neoplasms (eg, melanoma, basal cell epithelioma, squamous cell carcinoma, lymphoma) produced striking neovascularization; vascular tumors (eg, Kaposi sarcoma, pyogenic granuloma, vascular histiocytoma) stimulated dramatic hyperemia and ectasia. Angiogenesis was conspicuously absent after implantation of control materials and nevoid or normal cutaneous components (with the exception of epidermis). Tumor angiogenic factor appears to induce direct stimulation of endothelial cell mitosis and may be essential for survival of nutritionally ravenous neoplastic tissues. The interference with TAF has therapeutic implications.

  11. hCG stimulates angiogenic signals in lymphatic endothelial and circulating angiogenic cells.

    Science.gov (United States)

    Schanz, Andrea; Lukosz, Margarete; Hess, Alexandra P; Baston-Büst, Dunja M; Krüssel, Jan S; Heiss, Christian

    2015-08-01

    Human chorionic gonadotropin (hCG) has long been associated with the initiation and maintenance of pregnancy, where angiogenesis plays an important role. However, the function of hCG in angiogenesis and the recruitment of vascular active cells are not fully understood. In this study, the role of hCG and its receptor in circulating angiogenic and human endothelial cells, including lymphatic, uterine microvascular, and umbilical vein endothelial cells, was examined. Immunohistochemistry and immunoblot analysis were used to detect LH/hCG receptor expression and the expression of hCG-induced angiogenic molecules. HIF-1α was determined via ELISA and downstream molecules, such as CXCL12 and CXCR4, via real-time PCR. Chemotaxis was analyzed using Boyden chambers. Our results show that the LH/hCG receptor was present in all tested cells. Furthermore, hCG was able to stimulate LH/hCG-receptor-specific migration in a dose-dependent fashion and induce key angiogenic molecules, including HIF-1α, CXCL12, and CXCR4. In conclusion, our findings underscore the importance of hCG as one of the first angiogenic molecules produced by the conceptus. hCG itself alters endothelial motility, recruitment, and expression of pro-angiogenic molecules and may therefore play an important role in vascular adaption during implantation and early placental formation. Copyright © 2015. Published by Elsevier Ireland Ltd.

  12. Bacterial Toxins: A Hope Towards Angiogenic Ailments.

    Science.gov (United States)

    Khandia, Rekha; Munjal, Ashok; Dhama, Kuldeep; Malik, Yashpal Singh

    2017-01-01

    Angiogenesis is an essential physiological process for growth and maintenance of the body. Especially its role becomes indispendable during the embryonic development stage but lacks in adults with some exceptions like while wound repair and menstrual cycle. It is a tightly regulated process and relies on the cascade of several molecular signaling pathways with the involvement of many effectors like vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), platelet-derived growth factor (PDGF), insulin-like growth factor (IGF) etc. Related literature/ information were retrieved, analyzed and compiled from the online published resources available in Medline, Pubmed, Pubmed Central, Science Direct and other scientific databases. Excessive angiogenesis leads to disorders like tumor, atherosclerosis, rheumatoid arthritis, diabetic retinopathy, endometriosis, psoriasis, and adiposity. While, reduced angiogenesis also results in several ailments like cardiac ischemia, low capillary density in brain of Alzheimer's patients and delayed wound healing. Therefore, both angio-proliferative and anti-angiogenic approaches may be of use in developing novel therapeutics. Bacterial toxins are known for modulating the process of angiogenesis by mimicking pro-angiogenic factors and/ or competing with them. Furthermore, they inactivate the receptors or keep them in ON status, hence can be used to treat angiogenic disorders. The ease in handling, cultivation and manipulating the toxins structure has enabled the use of bacteria as an ideal choice for novel therapeutic developments. This review intends to elucidate the molecular mechanisms through which certain bacteria may alter the level of angiogenesis and consequently can work as therapeutics against angiogenic disorders. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  13. Alternatives to allograft corneal transplantation.

    Science.gov (United States)

    Jhanji, Vishal; Sharma, Namrata; Agarwal, Tushar; Vajpayee, Rasik B

    2010-07-01

    Corneal transplantation is the most commonly performed solid organ transplantation in the world. Despite a glorious history of more than a 100 years, the success of conventional corneal transplantation surgery is marred by problems like graft rejection,graft infection and associated glaucoma due to long-term use of topical corticosteroids.In addition there is a dearth of donor corneal tissue in some parts of the world which subsequently adds on to the existing burden on the eye banks every year. We propose alternatives to the conventional corneal transplantation surgery for the management of corneal scarring. The potential use of alternatives to allograft corneal transplantation surgery has been described by corneal surgeons around the world. These techniques consist of nonsurgical interventions like contact lens fitting. Surgical alternatives include excimer laser phototherapeutic keratectomy, optical iridectomy, rotational autokeratoplasty and contralateral autokeratoplasty. Although these techniques are not practiced routinely, however, their appropriate utilization would clearly help the corneal surgeons to get rid of certain problems associated with allograft corneal transplantation. Careful selection of patients can yield encouraging results with the use of these alternative techniques. Visual outcomes may not be as good as after a routine keratoplasty; nevertheless, this setback is outweighed by advantages such as absence of corneal graft rejection. We also believe that the use of these techniques would at least partially resolve the issue of scarcity of donor corneal tissue in the developing world.

  14. Spontaneous Corneal Hydrops in a Patient with a Corneal Ulcer

    Directory of Open Access Journals (Sweden)

    Hatim Batawi

    2016-01-01

    Full Text Available Purpose: We report the case of a 77-year-old man with no history of keratoconus or other ectatic disorders who presented with corneal hydrops in the setting of a corneal ulcer. The risk factors, pathogenesis and treatment options of corneal hydrops are discussed. Method: This is an observational case report study. Results: A 77-year-old man presented with a 1-day history of severe pain, redness, mucous discharge and photophobia in the right eye. A slit-lamp examination of the right eye showed an area of focal corneal edema and protrusion. Within the area of edema and protrusion, there was an infiltrate with an overlying epithelial defect consistent with an infectious corneal ulcer. The Seidel test showed no leakage, so a clinical diagnosis of corneal hydrops associated with nonperforated corneal ulcer was made. With appropriate antibiotic treatment, the corneal ulcer and hydrops both resolved over a 1-month period. Conclusion: Corneal hydrops can occur in the setting of corneal infections.

  15. Corneal biomechanical properties from air-puff corneal deformation imaging

    Science.gov (United States)

    Marcos, Susana; Kling, Sabine; Bekesi, Nandor; Dorronsoro, Carlos

    2014-02-01

    The combination of air-puff systems with real-time corneal imaging (i.e. Optical Coherence Tomography (OCT), or Scheimpflug) is a promising approach to assess the dynamic biomechanical properties of the corneal tissue in vivo. In this study we present an experimental system which, together with finite element modeling, allows measurements of corneal biomechanical properties from corneal deformation imaging, both ex vivo and in vivo. A spectral OCT instrument combined with an air puff from a non-contact tonometer in a non-collinear configuration was used to image the corneal deformation over full corneal cross-sections, as well as to obtain high speed measurements of the temporal deformation of the corneal apex. Quantitative analysis allows direct extraction of several deformation parameters, such as apex indentation across time, maximal indentation depth, temporal symmetry and peak distance at maximal deformation. The potential of the technique is demonstrated and compared to air-puff imaging with Scheimpflug. Measurements ex vivo were performed on 14 freshly enucleated porcine eyes and five human donor eyes. Measurements in vivo were performed on nine human eyes. Corneal deformation was studied as a function of Intraocular Pressure (IOP, 15-45 mmHg), dehydration, changes in corneal rigidity (produced by UV corneal cross-linking, CXL), and different boundary conditions (sclera, ocular muscles). Geometrical deformation parameters were used as input for inverse finite element simulation to retrieve the corneal dynamic elastic and viscoelastic parameters. Temporal and spatial deformation profiles were very sensitive to the IOP. CXL produced a significant reduction of the cornea indentation (1.41x), and a change in the temporal symmetry of the corneal deformation profile (1.65x), indicating a change in the viscoelastic properties with treatment. Combining air-puff with dynamic imaging and finite element modeling allows characterizing the corneal biomechanics in-vivo.

  16. A microarray whole-genome gene expression dataset in a rat model of inflammatory corneal angiogenesis.

    Science.gov (United States)

    Mukwaya, Anthony; Lindvall, Jessica M; Xeroudaki, Maria; Peebo, Beatrice; Ali, Zaheer; Lennikov, Anton; Jensen, Lasse Dahl Ejby; Lagali, Neil

    2016-11-22

    In angiogenesis with concurrent inflammation, many pathways are activated, some linked to VEGF and others largely VEGF-independent. Pathways involving inflammatory mediators, chemokines, and micro-RNAs may play important roles in maintaining a pro-angiogenic environment or mediating angiogenic regression. Here, we describe a gene expression dataset to facilitate exploration of pro-angiogenic, pro-inflammatory, and remodelling/normalization-associated genes during both an active capillary sprouting phase, and in the restoration of an avascular phenotype. The dataset was generated by microarray analysis of the whole transcriptome in a rat model of suture-induced inflammatory corneal neovascularisation. Regions of active capillary sprout growth or regression in the cornea were harvested and total RNA extracted from four biological replicates per group. High quality RNA was obtained for gene expression analysis using microarrays. Fold change of selected genes was validated by qPCR, and protein expression was evaluated by immunohistochemistry. We provide a gene expression dataset that may be re-used to investigate corneal neovascularisation, and may also have implications in other contexts of inflammation-mediated angiogenesis.

  17. Immunity and privilege of international organizations in Kosovo

    Directory of Open Access Journals (Sweden)

    Arif Riza

    2016-11-01

    Full Text Available To speak for the Diplomatic Law (Immunities and Privileges in International Organizations, first, this topic briefly describes the international organizations, what are they, as established, as extinct, and finally, as a shared international organizations. They are not subject of this paper, but Immunity and Privileges in International Organizations are. This paper gives an overview of the history of the immunity and privileges in international organizations, conventions, laws of the country regarding Immunities and Privileges, where the seat of the International Organization, Immunities and privileges of diplomatic representatives in international organizations, Immunities and privileges of representatives of international organizations in the state where the seat of the Organization, immunity and privileges of members of the family, diplomatic representatives International Organizations, Immunities and Privileges in the European Union, the difference between the immunity and privileges of international organizations, and Immunity and Privileges between states. This paper analyzes also the immunity and inviolability of buildings of International Organizations, immunity and inviolability of the archives of international organizations, the immunity and privileges of goods to international organizations, the release from the obligation of tax payments, the release from the provision of the diplomatic staff of International Organizations, etc. However, the paper includes charts, respectively, some official data from countries where the headquarters of international organizations are situated and gives an overview of the number of international governmental and nongovernmental organizations.

  18. Chalcone: A Privileged Structure in Medicinal Chemistry.

    Science.gov (United States)

    Zhuang, Chunlin; Zhang, Wen; Sheng, Chunquan; Zhang, Wannian; Xing, Chengguo; Miao, Zhenyuan

    2017-06-28

    Privileged structures have been widely used as an effective template in medicinal chemistry for drug discovery. Chalcone is a common simple scaffold found in many naturally occurring compounds. Many chalcone derivatives have also been prepared due to their convenient synthesis. These natural products and synthetic compounds have shown numerous interesting biological activities with clinical potentials against various diseases. This review aims to highlight the recent evidence of chalcone as a privileged scaffold in medicinal chemistry. Multiple aspects of chalcone will be summarized herein, including the isolation of novel chalcone derivatives, the development of new synthetic methodologies, the evaluation of their biological properties, and the exploration of the mechanisms of action as well as target identification. This review is expected to be a comprehensive, authoritative, and critical review of the chalcone template to the chemistry community.

  19. Populism, Prejudice and the Rhetoric of Privilege

    Directory of Open Access Journals (Sweden)

    Alberto Giordano

    2017-08-01

    Full Text Available The paper aims to show, by means of a close look at the most recent samples of political discourse in Europe and America, how much and how frequently populists set up their narratives around a relatively small number of patterns, such as the worship of the people, a (more or less overt appeal to prejudice and the rhetoric of privilege. In so doing, it offers some useful insights into the nature of contemporary populism.

  20. Computational Model for Corneal Transplantation

    Science.gov (United States)

    Cabrera, Delia

    2003-10-01

    We evaluated the refractive consequences of corneal transplants using a biomechanical model with homogeneous and inhomogeneous Young's modulus distributions within the cornea, taking into account ablation of some stromal tissue. A FEM model was used to simulate corneal transplants in diseased cornea. The diseased cornea was modeled as an axisymmetric structure taking into account a nonlinearly elastic, isotropic formulation. The model simulating the penetrating keratoplasty procedure gives more change in the postoperative corneal curvature when compared to the models simulating the anterior and posterior lamellar graft procedures. When a lenticle shaped tissue was ablated in the graft during the anterior and posterior keratoplasty, the models provided an additional correction of about -3.85 and -4.45 diopters, respectively. Despite the controversy around the corneal thinning disorders treatment with volume removal procedures, results indicate that significant changes in corneal refractive power could be introduced by a corneal transplantation combined with myopic laser ablation.

  1. Human corneal epithelial subpopulations

    DEFF Research Database (Denmark)

    Søndergaard, Chris Bath

    2013-01-01

    subpopulations in human corneal epithelium using a combination of laser capture microdissection and RNA sequencing for global transcriptomic profiling. We compared dissociation cultures, using either expansion on γ-irradiated NIH/3T3 feeder cells in serum-rich medium or expansion directly on plastic in serum......-free EpiLife medium, using a range of physiologically relevant oxygen concentrations (2%, 5%, 10%, 15% and 20%). Using immunocytochemistry and advanced fluorescence microscopy, cells were characterized regarding growth, cell cycle distribution, colony-forming efficiency (CFE), phenotypes...... was not dependent on the system used for propagation (Bath et al. 2013a). Laser capture microdissection was used to isolate cellular subpopulations in situ from the spatially defined differentiation pathway in human corneal epithelium according to an optimized protocol for maintenance of expression profiles...

  2. Biomechanics of Corneal Ring Implants

    OpenAIRE

    Daxer, Albert

    2015-01-01

    Purpose: To evaluate the biomechanics of corneal ring implants by providing a related mathematical theory and biomechanical model for the treatment of myopia and keratoconus. Methods: The spherical dome model considers the inhomogeneity of the tunica of the eye, dimensions of the cornea, lamellar structure of the corneal stroma, and asphericity of the cornea. It is used in this study for calculating a strengthening factor sf for the characterization of different ring-shaped corneal implant de...

  3. Corneal biomechanics: a review

    OpenAIRE

    Piñero Llorens, David Pablo; Alcón, Natividad

    2014-01-01

    Biomechanics is often defined as ‘mechanics applied to biology’. Due to the variety and complexity of the behaviour of biological structures and materials, biomechanics is better defined as the development, extension and application of mechanics for a better understanding of physiology and physiopathology and consequently for a better diagnosis and treatment of disease and injury. Different methods for the characterisation of corneal biomechanics are reviewed in detail, including those that a...

  4. Airbag-induced corneal flap.

    Science.gov (United States)

    Liyanage, Sidath E; Mearza, Ali A

    2009-02-01

    To describe a case of airbag-induced corneal flap in a previously normal cornea. Case report. A 27-year-old woman presented with complete loss of vision in her left eye following a road traffic accident which involved airbag deployment. There was no previous ocular history. Examination revealed a large corneal flap of 6mm in diameter, extending to the depth of anterior stroma. This was accompanied by a traumatic optic neuropathy. One month follow-up revealed complete reattachment of the corneal flap. This is the first reported case of a corneal flap induced by airbag deployment in a cornea with previously normal architecture.

  5. Minocycline inhibits alkali burn-induced corneal neovascularization in mice.

    Directory of Open Access Journals (Sweden)

    Ou Xiao

    Full Text Available The purpose of this study was to investigate the effects of minocycline on alkali burn-induced corneal neovascularization (CNV. A total of 105 mice treated with alkali burns were randomly divided into three groups to receive intraperitoneal injections of either phosphate buffered saline (PBS or minocycline twice a day (60 mg/kg or 30 mg/kg for 14 consecutive days. The area of CNV and corneal epithelial defects was measured on day 4, 7, 10, and14 after alkali burns. On day 14, a histopathological examination was performed to assess morphological change and the infiltration of polymorphonuclear neutrophils (PMNs. The mRNA expression levels of vascular endothelial growth factor (VEGF and its receptors (VEGFRs, basic fibroblast growth factor (bFGF, matrix metalloproteinases (MMPs, interleukin-1α, 1β, 6 (IL-1α, IL-1β, IL-6 were analyzed using real-time quantitative polymerase chain reaction. The expression of MMP-2 and MMP-9 proteins was determined by gelatin zymography. In addition, enzyme-linked immunosorbent assay was used to analyze the protein levels of VEGFR1, VEGFR2, IL-1β and IL-6. Minocycline at a dose of 60 mg/kg or 30 mg/kg significantly enhanced the recovery of the corneal epithelial defects more than PBS did. There were significant decreases of corneal neovascularization in the group of high-dosage minocycline compared with the control group at all checkpoints. On day 14, the infiltrated PMNs was reduced, and the mRNA expression of VEGFR1, VEGFR2, bFGF, IL-1β, IL-6, MMP-2, MMP-9, -13 as well as the protein expression of VEGFR2, MMP-2, -9, IL-1β, IL-6 in the corneas were down-regulated with the use of 60 mg/kg minocycline twice a day. Our results showed that the intraperitoneal injection of minocycline (60 mg/kg b.i.d. can significantly inhibit alkali burn-induced corneal neovascularization in mice, possibly by accelerating corneal wound healing and by reducing the production of angiogenic factors, inflammatory cytokines and MMPs.

  6. Correlations between corneal hysteresis, intraocular pressure, and corneal central pachymetry.

    Science.gov (United States)

    Touboul, David; Roberts, Cynthia; Kérautret, Julien; Garra, Caroline; Maurice-Tison, Sylvie; Saubusse, Elodie; Colin, Joseph

    2008-04-01

    To analyze the correlation between corneal hysteresis (CH) measured with the Ocular Response Analyzer (ORA, Reichert) and ultrasonic corneal central thickness (CCT US) and intraocular pressure measured with Goldmann applanation tonometry (IOP GA). Bordeaux 2 University, Ophthalmology Department, Bordeaux, France. This study comprised 498 eyes of 258 patients. Corneal hysteresis, corneal resistance factor (CRF), and IOP corneal-compensated (IOPcc) were provided by the ORA device; CCT US and IOP GA were also measured in each eye. The study population was divided into 5 groups: normal (n = 122), glaucoma (n = 159), keratoconus (n = 88), laser in situ keratomileusis (LASIK) (n = 78), and photorefractive keratectomy (n = 39). The Pearson correlation was used for statistical analysis. Corneal hysteresis was not strongly correlated with IOP or CCT US. The mean CH in the LASIK (8.87 mm Hg) and keratoconus (8.34 mm Hg) groups was lower than in the glaucoma (9.48 mm Hg) and normal (10.26 mm Hg) groups. The lower the CH, the lower its correlation with IOPcc and IOP GA. A CH higher than the CRF was significantly associated with the keratoconus and post-LASIK groups. Corneal hysteresis, a new corneal parameter, had a moderate dependence on IOP and CCT US. Weaker corneas could be screened with ORA parameters, and low CH could be considered a risk factor for underestimation of IOP. The CCT US should continue to be considered a useful parameter.

  7. Changes in corneal hysteresis after clear corneal cataract surgery.

    Science.gov (United States)

    Hager, Annette; Loge, Kristina; Füllhas, Marc-Oliver; Schroeder, Bernd; Grossherr, Martin; Wiegand, Wolfgang

    2007-09-01

    To assess the changes in corneal hysteresis (CH) as measured by the Ocular Response Analyzer (ORA; Reichert Ophthalmic Instruments, Buffalo, New York, USA) to describe the influence of clear corneal cataract surgery on corneal viscoelastic properties and intraocular pressure (IOP) measured by noncontact tonometry (NCT) and Goldmann applanation tonometry (GAT). Retrospective, interventional, comparative study. One hundred and one eyes of 101 consecutive patients who underwent routine clear corneal cataract surgery were evaluated. CH, NCT, and central corneal thickness (CCT) were measured by ORA before surgery and at postoperative day 1. A control group of 48 pseudophakic eyes (surgery >3 months previously) was included. CCT increased from 556.82 +/- 32.5 microm before surgery to 580.26 +/- 45.5 microm after surgery (P corneal cataract surgery, CH is diminished, whereas CCT is increased significantly. Postoperative corneal edema leads to a change of corneal viscoelastic properties, resulting in a lower damping capacity of the cornea. It is supposed that GAT and NCT measurements are significantly different because of postoperative changes in viscoelastic properties of the cornea.

  8. Pro-angiogenic properties of orosomucoid (ORM).

    Science.gov (United States)

    Irmak, Ster; Oliveira-Ferrer, Leticia; Singer, Bernhard B; Ergün, Süleyman; Tilki, Derya

    2009-11-01

    The acute phase protein orosomucoid (ORM), also known as alpha1-acid glycoprotein (AGP), is found to be increased in infection, inflammation and cancer. Recently, we demonstrated that ORM is produced by endothelial cells and detectable in urine samples of patients with bladder cancer. However, it was not clarified yet whether ORM plays a role in new vessel formation. To this aim we performed overexpression and gene silencing for ORM in human microvascular endothelial cells (HDMECs). ORM purified from human plasma was used individually or in combination with VEGF-A in endothelial tube formation, migration and proliferation assay. The in vivo effect of ORM in angiogenesis was studied using the chicken chorionallantois membrane (CAM) with subsequent counting of blood vessels on histological sections from the stimulated areas of CAM tissue. Our data show that ORM alone enhances migration but not proliferation of HDMECs. ORM alone does not induce endothelial tubes in vitro but simultaneous application of ORM with VEGF-A increases the number and the network of VEGF-A-induced endothelial tubes. Remarkably, ORM alone induces new vessel formation in vivo using CAM assay and supports the VEGF-A-induced new vessel formation in this assay. Taken together, our results let assume that ORM has pro-angiogenic properties and supports the angiogenic effect of VEGF-A. Thus, ORM seems to be involved in the regulation of angiogenesis.

  9. Tumour biology: Herceptin acts as an anti-angiogenic cocktail

    Science.gov (United States)

    Izumi, Yotaro; Xu, Lei; di Tomaso, Emmanuelle; Fukumura, Dai; Jain, Rakesh K.

    2002-03-01

    Malignant tumours secrete factors that enable them to commandeer their own blood supply (angiogenesis), and blocking the action of these factors can inhibit tumour growth. But because tumours may become resistant to treatments that target individual angiogenic factors by switching over to other angiogenic molecules, a cocktail of multiple anti-angiogenic agents should be more effective. Here we show that herceptin, a monoclonal antibody against the cell-surface receptor HER2 (for human epidermal growth factor receptor-2; ref. 4), induces normalization and regression of the vasculature in an experimental human breast tumour that overexpresses HER2 in mice, and that it works by modulating the effects of different pro- and anti-angiogenic factors. As a single agent that acts against multiple targets, herceptin, or drugs like it, may offer a simple alternative to combination anti-angiogenic treatments.

  10. Prolonging survival of corneal transplantation by selective sphingosine-1-phosphate receptor 1 agonist.

    Directory of Open Access Journals (Sweden)

    Min Gao

    Full Text Available Corneal transplantation is the most used therapy for eye disorders. Although the cornea is somewhat an immune privileged organ, immune rejection is still the major problem that reduces the success rate. Therefore, effective chemical drugs that regulate immunoreactions are needed to improve the outcome of corneal transplantations. Here, a sphingosine-1-phosphate receptor 1 (S1P1 selective agonist was systematically evaluated in mouse allogeneic corneal transplantation and compared with the commonly used immunosuppressive agents. Compared with CsA and the non-selective sphingosine 1-phosphate (S1P receptor agonist FTY720, the S1P1 selective agonist can prolong the survival corneal transplantation for more than 30 days with a low immune response. More importantly, the optimal dose of the S1P1 selective agonist was much less than non-selective S1P receptor agonist FTY720, which would reduce the dose-dependent toxicity in drug application. Then we analyzed the mechanisms of the selected S1P1 selective agonist on the immunosuppression. The results shown that the S1P1 selective agonist could regulate the distribution of the immune cells with less CD4+ T cells and enhanced Treg cells in the allograft, moreover the expression of anti-inflammatory cytokines TGF-β1 and IL-10 unregulated which can reduce the immunoreactions. These findings suggest that S1P1 selective agonist may be a more appropriate immunosuppressive compound to effectively prolong mouse allogeneic corneal grafts survival.

  11. Targeted decorin gene therapy delivered with adeno-associated virus effectively retards corneal neovascularization in vivo.

    Directory of Open Access Journals (Sweden)

    Rajiv R Mohan

    Full Text Available Decorin, small leucine-rich proteoglycan, has been shown to modulate angiogenesis in nonocular tissues. This study tested a hypothesis that tissue-selective targeted decorin gene therapy delivered to the rabbit stroma with adeno-associated virus serotype 5 (AAV5 impedes corneal neovascularization (CNV in vivo without significant side effects. An established rabbit CNV model was used. Targeted decorin gene therapy in the rabbit stroma was delivered with a single topical AAV5 titer (100 µl; 5×10(12 vg/ml application onto the stroma for two minutes after removing corneal epithelium. The levels of CNV were examined with stereomicroscopy, H&E staining, lectin, collagen type IV, CD31 immunocytochemistry and CD31 immunoblotting. Real-time PCR quantified mRNA expression of pro- and anti-angiogenic genes. Corneal health in live animals was monitored with clinical, slit-lamp and optical coherence tomography biomicroscopic examinations. Selective decorin delivery into stroma showed significant 52% (p<0.05, 66% (p<0.001, and 63% (p<0.01 reduction at early (day 5, mid (day 10, and late (day 14 stages of CNV in decorin-delivered rabbit corneas compared to control (no decorin delivered corneas in morphometric analysis. The H&E staining, lectin, collagen type IV, CD31 immunostaining (57-65, p<0.5, and CD31 immunoblotting (62-67%, p<0.05 supported morphometric findings. Quantitative PCR studies demonstrated decorin gene therapy down-regulated expression of VEGF, MCP1 and angiopoietin (pro-angiogenic and up-regulated PEDF (anti-angiogenic genes. The clinical, biomicroscopy and transmission electron microscopy studies revealed that AAV5-mediated decorin gene therapy is safe for the cornea. Tissue-targeted AAV5-mediated decorin gene therapy decreases CNV with no major side effects, and could potentially be used for treating patients.

  12. Immunity and privilege of international organizations in Kosovo

    OpenAIRE

    Arif Riza

    2016-01-01

    To speak for the Diplomatic Law (Immunities and Privileges) in International Organizations, first, this topic briefly describes the international organizations, what are they, as established, as extinct, and finally, as a shared international organizations. They are not subject of this paper, but Immunity and Privileges in International Organizations are. This paper gives an overview of the history of the immunity and privileges in international organizations, conventions, laws of the country...

  13. Privileging Peer Review: Implications for Undergraduates

    Directory of Open Access Journals (Sweden)

    Amy E. Mark

    2011-11-01

    Full Text Available Librarians and teaching faculty privilege peer review articles out of ideals rooted in academic culture more then for pedagogical reasons. Undergraduates would find greater benefit in the opportunity to search and critique sources related to their personal and creative interests as well as relevant to academic research projects. Librarians can adopt the role of change-agents by engaging relevant teaching faculty in discussions about the goal of research assignments relative to peer review literature. Framing this discussion is Paulo Freire’s theory of banking information discussed in Pedagogy of the Oppressed (2000.

  14. Construction of tissue-engineered cornea composed of amniotic epithelial cells and acellular porcine cornea for treating corneal alkali burn.

    Science.gov (United States)

    Luo, Hailang; Lu, Yongbo; Wu, Tiantian; Zhang, Mi; Zhang, Yongjie; Jin, Yan

    2013-09-01

    Although acellular corneas have been reported to be a potential substitute for allogeneic cornea transplantation to treat corneal injury, severe corneal injury is hard to repair due to inflammation and neovascularization. The use of the amniotic membrane as a graft in ocular surface reconstruction has become widespread because of the anti-inflammatory and anti-angiogenic properties of amniotic epithelial cells (AECs). Our objective was to construct a tissue-engineered cornea (TEC) composed of an acellular porcine cornea (APC) and AECs to repair severe corneal injury. Corneal cells were completely removed from the prepared APC, and the microstructure, mechanical properties, and stability of a natural porcine cornea (NPC) was maintained. In vitro, MTT and flow cytometry analyses showed that the APC did not negatively affect cell viability and apoptosis. In vivo, corneal pocket and subcutaneous transplantation demonstrated that the APC was incapable of trigging accepted immune response. AECs isolated from the human amniotic membrane have proliferation potential and present healthy morphology before 6 passages. After 7 days of culture on the surface of the APC, the AECs were stratified into 5-6 layers. We found that the AECs reconstituted the basement membrane that had been disrupted by the decellularization process. ELISA results showed that after culturing the TEC, the culture medium contained anti-inflammatory and anti-angiogenic growth factors, such as MIF, IL6, Fas-L, and PDEF. Finally, the results of lamellar keratoplasty to treat an alkali burn showed that the transplanted TEC was transparent and completely inoculated into the host cornea. However, the transplanted APC was degraded due to host rejection. Therefore, we conclude that a TEC composed of AECs and an APC holds great potential for the repair of severe corneal injury. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Role of corneal collagen fibrils in corneal disorders and related pathological conditions

    Directory of Open Access Journals (Sweden)

    Hong-Yan Zhou

    2017-05-01

    Full Text Available The cornea is a soft tissue located at the front of the eye with the principal function of transmitting and refracting light rays to precisely sense visual information. Corneal shape, refraction, and stromal stiffness are to a large part determined by corneal fibrils, the arrangements of which define the corneal cells and their functional behaviour. However, the modality and alignment of native corneal collagen lamellae are altered in various corneal pathological states such as infection, injury, keratoconus, corneal scar formation, and keratoprosthesis. Furthermore, corneal recuperation after corneal pathological change is dependent on the balance of corneal collagen degradation and contraction. A thorough understanding of the characteristics of corneal collagen is thus necessary to develop viable therapies using the outcome of strategies using engineered corneas. In this review, we discuss the composition and distribution of corneal collagens as well as their degradation and contraction, and address the current status of corneal tissue engineering and the progress of corneal cross-linking.

  16. IκB kinase β regulates epithelium migration during corneal wound healing.

    Directory of Open Access Journals (Sweden)

    Liang Chen

    2011-01-01

    Full Text Available The IKKβ is known to regulate transcription factor NF-κB activation leading to inflammatory responses. Recent gene knockout studies have shown that IKKβ can orchestrate local inflammatory responses and regulate homeostasis of epithelial tissues. To investigate whether IKKβ has an intrinsic role in epithelial cells, we established an in vivo system in the immune privileged corneal epithelium. We generated triple transgenic Krt12(rtTA/rtTAt/tet-O-Cre/Ikkβ(F/F (Ikkβ(ΔCE/ΔCE mice by crossing the Krt12-rtTA knock-in mice, which express the reverse tetracycline transcription activator in corneal epithelial cells, with the tet-O-Cre and Ikkβ(F/F mice. Doxycycline-induced IKKβ ablation occurred in corneal epithelial cells of triple transgenic Ikkβ(ΔCE/ΔCE mice, but loss of IKKβ did not cause ocular abnormalities in fetal development and postnatal maintenance. Instead, loss of IKKβ significantly delayed healing of corneal epithelial debridement without affecting cell proliferation, apoptosis or macrophage infiltration. In vitro studies with human corneal epithelial cells (HCEpi also showed that IKKβ was required for cytokine-induced cell migration and wound closure but was dispensable for cell proliferation. In both in vivo and in vitro settings, IKKβ was required for optimal activation of NF-κB and p38 signaling in corneal epithelial cells, and p38 activation is likely mediated through formation of an IKKβ-p38 protein complex. Thus, our studies in corneal epithelium reveal a previously un-recognized role for IKKβ in the control of epithelial cell motility and wound healing.

  17. Early pregnancy angiogenic markers and spontaneous abortion

    DEFF Research Database (Denmark)

    Andersen, Louise B; Dechend, Ralf; Karumanchi, S Ananth

    2016-01-01

    BACKGROUND: Spontaneous abortion is the most commonly observed adverse pregnancy outcome. The angiogenic factors soluble Fms-like kinase 1 and placental growth factor are critical for normal pregnancy and may be associated to spontaneous abortion. OBJECTIVE: We investigated the association between...... maternal serum concentrations of soluble Fms-like kinase 1 and placental growth factor, and subsequent spontaneous abortion. STUDY DESIGN: In the prospective observational Odense Child Cohort, 1676 pregnant women donated serum in early pregnancy, gestational week ..., interquartile range 71-103). Concentrations of soluble Fms-like kinase 1 and placental growth factor were determined with novel automated assays. Spontaneous abortion was defined as complete or incomplete spontaneous abortion, missed abortion, or blighted ovum

  18. Anti-angiogenic peptides for cancer therapeutics.

    Science.gov (United States)

    Rosca, Elena V; Koskimaki, Jacob E; Rivera, Corban G; Pandey, Niranjan B; Tamiz, Amir P; Popel, Aleksander S

    2011-08-01

    Peptides have emerged as important therapeutics that are being rigorously tested in angiogenesis-dependent diseases due to their low toxicity and high specificity. Since the discovery of endogenous proteins and protein fragments that inhibit microvessel formation (thrombospondin, endostatin) several peptides have shown promise in pre-clinical and clinical studies for cancer. Peptides have been derived from thrombospondin, collagens, chemokines, coagulation cascade proteins, growth factors, and other classes of proteins and target different receptors. Here we survey recent developments for anti-angiogenic peptides with length not exceeding 50 amino acid residues that have shown activity in pre-clinical models of cancer or have been tested in clinical trials; some of the peptides have been modified and optimized, e.g., through L-to-D and non-natural amino acid substitutions. We highlight technological advances in peptide discovery and optimization including computational and bioinformatics tools and novel experimental techniques.

  19. Angiogenic Profiling of Synthesized Carbon Quantum Dots.

    Science.gov (United States)

    Shereema, R M; Sruthi, T V; Kumar, V B Sameer; Rao, T P; Shankar, S Sharath

    2015-10-20

    A simple method was employed for the synthesis of green luminescent carbon quantum dots (CQDs) from styrene soot. The CQDs were characterized by transmission electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared, and Raman spectroscopy. The prepared carbon quantum dots did not show cellular toxicity and could successfully be used for labeling cells. We also evaluated the effects of carbon quantum dots on the process of angiogenesis. Results of a chorioallantoic membrane (CAM) assay revealed the significant decrease in the density of branched vessels after their treatment with CQDs. Further application of CQDs significantly downregulated the expression levels of pro-angiogenic growth factors like VEGF and FGF. Expression of VEGFR2 and levels of hemoglobin were also significantly lower in CAMs treated with CQDs, indicating that the CQDs inhibit angiogenesis. Data presented here also show that CQDs can selectively target cancer cells and therefore hold potential in the field of cancer therapy.

  20. Fluid shear stress threshold regulates angiogenic sprouting.

    Science.gov (United States)

    Galie, Peter A; Nguyen, Duc-Huy T; Choi, Colin K; Cohen, Daniel M; Janmey, Paul A; Chen, Christopher S

    2014-06-03

    The density and architecture of capillary beds that form within a tissue depend on many factors, including local metabolic demand and blood flow. Here, using microfluidic control of local fluid mechanics, we show the existence of a previously unappreciated flow-induced shear stress threshold that triggers angiogenic sprouting. Both intraluminal shear stress over the endothelium and transmural flow through the endothelium above 10 dyn/cm(2) triggered endothelial cells to sprout and invade into the underlying matrix, and this threshold is not impacted by the maturation of cell-cell junctions or pressure gradient across the monolayer. Antagonizing VE-cadherin widened cell-cell junctions and reduced the applied shear stress for a given transmural flow rate, but did not affect the shear threshold for sprouting. Furthermore, both transmural and luminal flow induced expression of matrix metalloproteinase 1, and this up-regulation was required for the flow-induced sprouting. Once sprouting was initiated, continuous flow was needed to both sustain sprouting and prevent retraction. To explore the potential ramifications of a shear threshold on the spatial patterning of new sprouts, we used finite-element modeling to predict fluid shear in a variety of geometric settings and then experimentally demonstrated that transmural flow guided preferential sprouting toward paths of draining interstitial fluid flow as might occur to connect capillary beds to venules or lymphatics. In addition, we show that luminal shear increases in local narrowings of vessels to trigger sprouting, perhaps ultimately to normalize shear stress across the vasculature. Together, these studies highlight the role of shear stress in controlling angiogenic sprouting and offer a potential homeostatic mechanism for regulating vascular density.

  1. Allergic Conjunctivitis Renders CD4+ T Cells Resistant to T Regulatory Cells and Exacerbates Corneal Allograft Rejection

    Science.gov (United States)

    Reyes, Nancy J.; Chen, Peter W.; Niederkorn, Jerry Y.

    2013-01-01

    Allergic diseases rob corneal allografts of immune privilege and increase immune rejection. Corneal allograft rejection in BALB/c allergic hosts was analyzed using a short ragweed (SWR) pollen model of allergic conjunctivitis. Allergic conjunctivitis did not induce exaggerated T cell responses to donor C57BL/6 (B6) alloantigens or stimulate cytotoxic T lymphocyte (CTL) responses. Allergic conjunctivitis did affect T regulatory cells (Tregs) that support graft survival. Exogenous IL-4, but not IL-5 or IL-13, prevented Treg suppression of CD4+ effector T cells isolated from naïve mice. However, mice with allergic conjunctivitis developed Tregs that suppressed CD4+ effector T cell proliferation. In addition, IL-4 did not inhibit Treg suppression of IL-4Rα−/− CD4+ T cell responses, suggesting that IL-4 rendered effector T cells resistant to Tregs. SRW-sensitized IL-4Rα−/− mice displayed the same 50% graft survival as non-allergic WT mice, that was significantly less than the 100% rejection that occurred in allergic WT hosts, supporting the role of IL-4 in the abrogation of immune privilege. Moreover, exacerbation of corneal allograft rejection in allergic mice was reversed by administering anti-IL-4 antibody. Thus, allergy-induced exacerbation of corneal graft rejection is due to the production of IL-4, which renders effector T cells resistant to Treg suppression of alloimmune responses. PMID:23489547

  2. Corneal structure and transparency

    Science.gov (United States)

    Meek, Keith M.; Knupp, Carlo

    2015-01-01

    The corneal stroma plays several pivotal roles within the eye. Optically, it is the main refracting lens and thus has to combine almost perfect transmission of visible light with precise shape, in order to focus incoming light. Furthermore, mechanically it has to be extremely tough to protect the inner contents of the eye. These functions are governed by its structure at all hierarchical levels. The basic principles of corneal structure and transparency have been known for some time, but in recent years X-ray scattering and other methods have revealed that the details of this structure are far more complex than previously thought and that the intricacy of the arrangement of the collagenous lamellae provides the shape and the mechanical properties of the tissue. At the molecular level, modern technologies and theoretical modelling have started to explain exactly how the collagen fibrils are arranged within the stromal lamellae and how proteoglycans maintain this ultrastructure. In this review we describe the current state of knowledge about the three-dimensional stromal architecture at the microscopic level, and about the control mechanisms at the nanoscopic level that lead to optical transparency. PMID:26145225

  3. Tissue Engineering of Corneal Endothelium

    Directory of Open Access Journals (Sweden)

    Satoru Yamagami

    2012-10-01

    Full Text Available Human corneal endothelial cells (HCECs do not replicate after wounding. Therefore, corneal endothelial deficiency can result in irreversible corneal edema. Descemet stripping automated endothelial keratoplasty (DSAEK allows selective replacement of the diseased corneal endothelium. However, DSAEK requires a donor cornea and the worldwide shortage of corneas limits its application. This review presents current knowledge on the tissue engineering of corneal endothelium using cultured HCECs. We also provide our recent work on tissue engineering for DSAEK grafts using cultured HCECs. We reconstructed DSAEK grafts by seeding cultured DiI-labelled HCECs on collagen sheets. Then HCEC sheets were transplanted onto the posterior stroma after descemetorhexis in the DSAEK group. Severe stromal edema was detected in the control group, but not in the DSAEK group throughout the observation period. Fluorescein microscopy one month after surgery showed numerous DiI-labelled cells on the posterior corneal surface in the DSAEK group. Frozen sections showed a monolayer of DiI-labelled cells on Descemet’s membrane. These findings indicate that cultured adult HCECs, transplanted with DSAEK surgery, maintain corneal transparency after transplantation and suggest the feasibility of performing DSAEK with HCECs to treat endothelial dysfunction.

  4. Teaching Note: Teaching about Privilege and Feminist Research Ethics

    Science.gov (United States)

    Sgoutas, Arlene

    2013-01-01

    This essay looks primarily at one approach to teaching about privilege in a feminist research course. I talk about the motivation to ask students to participate in this exercise and the potential as well as the challenges it has for raising awareness of one's own privileges before setting out to do feminist research. Additionally, the paper…

  5. 14 CFR 61.133 - Commercial pilot privileges and limitations.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Commercial pilot privileges and limitations... TRANSPORTATION (CONTINUED) AIRMEN CERTIFICATION: PILOTS, FLIGHT INSTRUCTORS, AND GROUND INSTRUCTORS Commercial Pilots § 61.133 Commercial pilot privileges and limitations. (a) Privileges—(1) General. A person who...

  6. 12 CFR 266.4 - Suspension of appearance privilege.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Suspension of appearance privilege. 266.4 Section 266.4 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE FEDERAL... of appearance privilege. If any person knowingly and willfully fails to comply with the provisions of...

  7. Are Student Communications with School Psychologists Legally Privileged?

    Science.gov (United States)

    Kaplan, Ross; Zirkel, Perry A.

    2017-01-01

    As a trusted link between district personnel, students, and their families, school psychologists often have questions about whether their communications are privileged like those of other professionals. In some jurisdictions, state statutes and common, or case, law recognize privileged communications for certain specified paired roles, including…

  8. The Ethical Issues of Privacy, Confidentiality and Privileged Communication.

    Science.gov (United States)

    Nunnelly, Diane T.

    School psychologists and other educators should be concerned about the issues of confidentiality, privacy and privileged communication in regard to school records such as psychological reports and intelligence test scores. Confidentiality relates to matters of professional ethics, privileged communication refers to legal rights, and privacy is a…

  9. Cultural Anarchism: The Consequences of Privileging Languages in Nepal

    Science.gov (United States)

    Giri, Ram Ashish

    2010-01-01

    Nepali, the official language of administration of Nepal, has been privileged through systematic political manoeuvres throughout its history. English also enjoys special status and privileges, and despite the fact that it is officially only a "foreign" language, in practice it is one of the most dominant languages in educational and…

  10. Making Unseen Privilege Visible in Mathematics Education Research

    Science.gov (United States)

    Bartell, Tonya Gau; Johnson, Kate R.

    2013-01-01

    In this essay, the authors begin to "unpack the invisible knapsack" of mathematics education research privilege. They present short statements representing the multiplicity of their respective identities; acknowledging that efforts to understand privilege and oppression are often supported and constrained by identities. The authors then…

  11. 14 CFR 1261.317 - Attorney-client privilege.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Attorney-client privilege. 1261.317 Section... Injury or Death-Accruing On or After January 18, 1967 § 1261.317 Attorney-client privilege. (a) Attorneys... traditional attorney-client relationship with the employee with respect to application of the attorney-client...

  12. Perks for Players: High School Teachers' Perceptions of Athletic Privilege

    Science.gov (United States)

    Fuller, Rhema D.; Lawrence, S. Malia; Harrison, C. Keith; Eyanson, Jeff; Osika, Lauren

    2017-01-01

    The purpose of the study reported in this article was to investigate high school teachers' perceptions of special privilege given to student-athletes. Additionally, researchers sought to explore teachers' perceptions as to why these privileges exist and who controls them. Qualitative data were collected from the teaching staff (N = 40) at one high…

  13. 77 FR 15286 - Confidential Treatment of Privileged Information

    Science.gov (United States)

    2012-03-15

    ... example, the attorney-client privilege and attorney work product protection. The prudential regulators... financial laws, and to prevent evasions thereof,'' \\7\\ the Bureau proposes to promulgate a rule providing... attorney-client privilege, to assess effectively the adequacy of supervised entities' compliance with...

  14. 49 CFR 1544.237 - Flight deck privileges.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 9 2010-10-01 2010-10-01 false Flight deck privileges. 1544.237 Section 1544.237... COMMERCIAL OPERATORS Operations § 1544.237 Flight deck privileges. (a) For each aircraft that has a door to the flight deck, each aircraft operator must restrict access to the flight deck as provided in its...

  15. 14 CFR 61.193 - Flight instructor privileges.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Flight instructor privileges. 61.193... (CONTINUED) AIRMEN CERTIFICATION: PILOTS, FLIGHT INSTRUCTORS, AND GROUND INSTRUCTORS Flight Instructors Other than Flight Instructors With a Sport Pilot Rating § 61.193 Flight instructor privileges. A person who...

  16. Corneal Confocal Microscopy Detects Corneal Nerve Damage in Patients Admitted With Acute Ischemic Stroke.

    Science.gov (United States)

    Khan, Adnan; Akhtar, Naveed; Kamran, Saadat; Ponirakis, Georgios; Petropoulos, Ioannis N; Tunio, Nahel A; Dargham, Soha R; Imam, Yahia; Sartaj, Faheem; Parray, Aijaz; Bourke, Paula; Khan, Rabia; Santos, Mark; Joseph, Sujatha; Shuaib, Ashfaq; Malik, Rayaz A

    2017-11-01

    Corneal confocal microscopy can identify corneal nerve damage in patients with peripheral and central neurodegeneration. However, the use of corneal confocal microscopy in patients presenting with acute ischemic stroke is unknown. One hundred thirty patients (57 without diabetes mellitus [normal glucose tolerance], 32 with impaired glucose tolerance, and 41 with type 2 diabetes mellitus) admitted with acute ischemic stroke, and 28 age-matched healthy control participants underwent corneal confocal microscopy to quantify corneal nerve fiber density, corneal nerve branch density, and corneal nerve fiber length. There was a significant reduction in corneal nerve fiber density, corneal nerve branch density, and corneal nerve fiber length in stroke patients with normal glucose tolerance ( P stroke. Corneal confocal microscopy is a rapid noninvasive ophthalmic imaging technique that identifies corneal nerve fiber loss in patients with acute ischemic stroke. © 2017 American Heart Association, Inc.

  17. PRIVILEGES AND IMMUNITIES IN SWITZERLAND - PRACTICAL GUIDE

    CERN Multimedia

    Relations with the Host States Service

    2002-01-01

    The Permanent Mission of Switzerland to the International Organisations in Geneva has just published a practical guide to the implementation of the system of privileges and immunities and other facilities on its Web site. The guide is currently available in French only but an English translation is in preparation. Comprising around ten chapters, each dealing with a different subject (insurance, real estate, customs, etc.), the guide is not exhaustive but will be regularly supplemented, expanded and updated. The Mission specifies that the information contained in the document is given only as guide and that it implies no legal commitment on the part of the Host State. Relations with the Host States Service Tel. 72848

  18. PRIVILEGES AND IMMUNITIES IN SWITZERLAND: PRACTICAL GUIDE

    CERN Multimedia

    2003-01-01

    The Permanent Mission of Switzerland to the International Organisations in Geneva has informed CERN that the "Practical Manual of the regime of privileges and immunities and other facilities" is available on its Web site: - in English (http://www.dfae.admin.ch/geneva_miss/e/home/guide.html); - in French (http://www.dfae.admin.ch/geneva_miss/f/home/guide.html). Comprising around ten chapters, each dealing with a different subject (insurance, real estate, customs, etc.), the guide is not exhaustive but will be regularly supplemented, expanded and updated. The Mission specifies that the information contained in the document is given only as guide and that it implies no legal commitment on the part of the Host State. Relations with the Host States Service http://www.cern.ch/relations/ Tel. 72848

  19. Corneal Biomechanical Findings in Contact Lens Induced Corneal Warpage

    OpenAIRE

    Fateme Alipour; Mojgan Letafatnejad; Amir Hooshang Beheshtnejad; Seyed-Farzad Mohammadi; Seyed Reza Ghaffary; Narges Hassanpoor; Mehdi Yaseri

    2016-01-01

    Purpose. To evaluate the difference in biomechanical properties between contact lens induced corneal warpage and normal and keratoconic eyes. Method. Prospective observational case control study, where 94 eyes of 47 warpage suspicious and 46 eyes of 23 keratoconic patients were included. Warpage suspected cases were followed until a definite diagnosis was made (warpage, normal, or keratoconus). Results. 44 eyes of 22 patients had contact lens related corneal warpage. 46 eyes of 23 people were...

  20. Intrastromal Corneal Ring Implants for Corneal Thinning Disorders

    Science.gov (United States)

    2009-01-01

    Executive Summary Objective The purpose of this project was to determine the role of corneal implants in the management of corneal thinning disease conditions. An evidence-based review was conducted to determine the safety, effectiveness and durability of corneal implants for the management of corneal thinning disorders. The evolving directions of research in this area were also reviewed. Subject of the Evidence-Based Analysis The primary treatment objectives for corneal implants are to normalize corneal surface topography, improve contact lens tolerability, and restore visual acuity in order to delay or defer the need for corneal transplant. Implant placement is a minimally invasive procedure that is purported to be safe and effective. The procedure is also claimed to be adjustable, reversible, and both eyes can be treated at the same time. Further, implants do not limit the performance of subsequent surgical approaches or interfere with corneal transplant. The evidence for these claims is the focus of this review. The specific research questions for the evidence review were as follows: Safety Corneal Surface Topographic Effects: Effects on corneal surface remodelling Impact of these changes on subsequent interventions, particularly corneal transplantation (penetrating keratoplasty [PKP]) Visual Acuity Refractive Outcomes Visual Quality (Symptoms): such as contrast vision or decreased visual symptoms (halos, fluctuating vision) Contact lens tolerance Functional visual rehabilitation and quality of life Patient satisfaction: Disease Process: Impact on corneal thinning process Effect on delaying or deferring the need for corneal transplantation Clinical Need: Target Population and Condition Corneal ectasia (thinning) comprises a range of disorders involving either primary disease conditions such as keratoconus and pellucid marginal corneal degeneration or secondary iatrogenic conditions such as corneal thinning occurring after LASIK refractive surgery. The condition

  1. Angiogenic activity of Calendula officinalis flowers L. in rats.

    Science.gov (United States)

    Parente, Leila Maria Leal; Andrade, Maria Auxiliadora; Brito, Luiz Augusto Batista; Moura, Veridiana Maria Brianezi Dignani de; Miguel, Marina Pacheco; Lino-Júnior, Ruy de Souza; Tresvenzol, Leonice Faustino Manrique; Paula, José Realino de; Paulo, Neusa Margarida

    2011-02-01

    In this work, angiogenic activity of Calendula officinalis L. (Asteraceae) ethanolic extract and dichloromethane and hexanic fractions were evaluated, considering medicinal properties, especially healing activity, are attributed to this plant. Models using 36 rats and 90 embryonated eggs were used to evaluate healing and angiogenic activities of extracts and fractions of the plant, through the induction of skin wounds and the chorioallantoic membrane, respectively. The effect of vascular proliferation was also tested from the study to verify the intensity of expression of vascular endothelial growth factor (VEGF) in cutaneous wounds in rats. The angiogenic activity of the extract and the fractions was evidenced in both experimental models. It was verified that this effect is not directly related to the expression of VEGF and it could be associated to other pro-angiogenic factors. The healing activity referred to C. officinalis is related, among other factors, to its positive effect on angiogenesis, characterized by the induction of neovascularization.

  2. Anti-Angiogenic Therapeutic Indictors in Breast Cancer

    National Research Council Canada - National Science Library

    Su, Min-Ying

    2003-01-01

    This project studies the therapeutic indicators in ant-angiogenic therapy. Every animal with mammary tumor was scheduled to receive a baseline MRI, core biopsy, then followed by 4 treatments with weekly MRI follow...

  3. Angiogenic factors in preeclampsia: potential for diagnosis and treatment.

    Science.gov (United States)

    Goel, Arvind; Rana, Sarosh

    2013-11-01

    The review summarizes new observations of key roles for circulating angiogenic factors in diagnosing, managing, and treating preeclampsia. Alterations in circulating angiogenic factors (soluble fms-like tyrosine kinase-1 and placental growth factor) in preeclampsia correlate with the diagnosis and adverse outcomes, particularly when the disease presents prematurely (preeclampsia and its complications from other disorders that present with similar clinical profiles. A ratio of soluble fms-like tyrosine kinase-1/placental growth factor greater than 85 appears ideal as the cut-off for both diagnosis and prognosis. There is also evidence that modulating these factors has therapeutic effects, suggesting a future role for angiogenic factors in treatment and prevention of preeclampsia. Circulating angiogenic biomarkers help in diagnostic and prognostic profiling of preeclampsia and may facilitate better management of these patients.

  4. Can the Lung Cancer Pie Be Divided into Angiogenic Slices?

    Science.gov (United States)

    Cascone, Tina; Heymach, John V

    2015-12-01

    There are no validated markers for predicting benefit from angiogenesis inhibitors or classifying tumors with distinct angiogenic phenotypes. In patients with non-small cell lung cancer treated with bevacizumab and erlotinib, Franzini and colleagues find that angiogenesis- and hypoxia-associated gene expression signatures predict tumor response and/or clinical outcome, and may define distinct angiogenic patterns. ©2015 American Association for Cancer Research.

  5. Search for Anti-angiogenic Substances from Natural Sources.

    Science.gov (United States)

    Kotoku, Naoyuki; Arai, Masayoshi; Kobayashi, Motomasa

    2016-01-01

    As angiogenesis is critical for tumor growth and metastasis, potent and selective anti-angiogenic agents with novel modes of action are highly needed for anti-cancer drug discovery. In this review, our studies focusing on the search for anti-angiogenic substances from natural sources, such as bastadins, globostellatic acid X methyl esters and cortistatins from marine sponges, and pyripyropenes from marine-derived fungus, together with senegasaponins from medicinal plant, are summarized.

  6. [Transplantation of corneal endothelial cells].

    Science.gov (United States)

    Amano, Shiro

    2002-12-01

    Though conventional corneal transplantation has achieved great success, it still has several drawbacks including limited availability of donor corneas, recurrent allograft rejection, and subsequent graft failure in certain cases. Reconstructing clinically usable corneas by applying the technology of regenerative medicine can offer a solution to these problems, as well as making corneal transplantation a non-emergency surgery and enabling the usage of banked corneal cells. In the present study, we focused on corneal endothelium that is critical for corneal transparency and investigated the reconstruction of cornea utilizing cultured human corneal endothelial cells (HCECs). We succeeded in steadily culturing HCECs by using culture dishes pre-coated with extracellular matrix produced by calf corneal endothelial cells and culture media that contained basic fibroblast growth factor and fetal bovine serum. We performed the following analysis utilizing these cultured HCECs. The older the donor was, the more frequently large senescent cells appeared in the passaged HCECs. The telomeres of HCECs were measured as terminal restriction fragments (TRF) by Southern blotting. HCECs, in vivo from donors in their seventies had a long TRFs of over 12 kilobases. Passaging shortened the TRFs but there was no difference in TRFs among donors of various ages. These results indicated that shortening of telomere length is not related to senescence of HCECs. We investigated the role of advanced glycation end products (AGEs) in the senescence of in vivo HCECs. The results indicated that AGE-protein in the aqueous humor is endocytosed into HCECs via AGE receptors expressed on the surface of HCECs and damages HCECs by producing reactive oxygen species and inducing apoptosis, suggesting that AGEs, at least partly, cause the senescence of HECEs. HCECs were cultured using adult human serum instead of bovine serum to get rid of bovine material that can be infected with prions. Primary and passage

  7. Identification of a potent endothelium-derived angiogenic factor.

    Directory of Open Access Journals (Sweden)

    Vera Jankowski

    Full Text Available The secretion of angiogenic factors by vascular endothelial cells is one of the key mechanisms of angiogenesis. Here we report on the isolation of a new potent angiogenic factor, diuridine tetraphosphate (Up4U from the secretome of human endothelial cells. The angiogenic effect of the endothelial secretome was partially reduced after incubation with alkaline phosphatase and abolished in the presence of suramin. In one fraction, purified to homogeneity by reversed phase and affinity chromatography, Up4U was identified by MALDI-LIFT-fragment-mass-spectrometry, enzymatic cleavage analysis and retention-time comparison. Beside a strong angiogenic effect on the yolk sac membrane and the developing rat embryo itself, Up4U increased the proliferation rate of endothelial cells and, in the presence of PDGF, of vascular smooth muscle cells. Up4U stimulated the migration rate of endothelial cells via P2Y2-receptors, increased the ability of endothelial cells to form capillary-like tubes and acts as a potent inducer of sprouting angiogenesis originating from gel-embedded EC spheroids. Endothelial cells released Up4U after stimulation with shear stress. Mean total plasma Up4U concentrations of healthy subjects (N=6 were sufficient to induce angiogenic and proliferative effects (1.34 ± 0.26 nmol L(-1. In conclusion, Up4U is a novel strong human endothelium-derived angiogenic factor.

  8. Corneal epithelium following penetrating keratoplasty.

    OpenAIRE

    Tsubota, K; Mashima, Y; Murata, H; Yamada, M.; Sato, N.

    1995-01-01

    AIMS--This study was designed to observe any changes to the corneal epithelium after penetrating keratoplasty. METHODS--The corneal epithelia of 26 patients were observed by specular microscopy 1 week, 1 month, 3 months, and 6 months following penetrating keratoplasty. RESULTS--After re-epithelialisation was confirmed by biomicroscopy 1 week after surgery, specular microscopy revealed many abnormal cells, including spindle shaped cells, nucleated cells, large cells, as well as irregular cell ...

  9. Corneal Topographic Changes After Eyelid Ptosis Surgery.

    Science.gov (United States)

    Savino, Gustavo; Battendieri, Remo; Riso, Monica; Traina, Salvatore; Poscia, Andrea; DʼAmico, Giovanni; Caporossi, Aldo

    2016-04-01

    To evaluate the corneal topography and the topographic changes after ptosis surgery on patients affected by congenital and acquired blepharoptosis. Twenty eyes of 17 patients affected by acquired and congenital ptosis underwent surgical correction through anterior levator complex tightening. Computerized tomography (Syrius Sistem; CSO) was used to analyze any change in corneal astigmatism (CYL), simulated keratometry, anterior corneal symmetry index front, apical keratometry front, and central corneal thickness. Visual acuity, margin reflex distance, and levator function were also measured. After surgical ptosis repair, corneal topography demonstrated a reduction in average keratometry of 0.15 ± 0.47 diopters (D) and in corneal astigmatism of 0.26 ± 1.12 D. Significant differences were found in apical keratometry front (-1.84 ± 1.76 D) and in best-corrected visual acuity (-0.18 ± 0.06 logMAR) in the postoperative examinations. Central corneal thickness did not show significant differences between preoperative and postoperative examinations. Postoperative topographic maps showed a reduction of symmetry index front (0.10 ± 0.64 D). Eyelid ptosis modifies anterior corneal surface inducing refractive errors and modifying corneal astigmatism in patients, thus affecting the quality of vision. The surgical correction of blepharoptosis induces anterior corneal surface modification, restoring corneal symmetry and regular corneal astigmatism. Postoperative corneal topography showed normal corneal contours.

  10. Biomechanical model of corneal transplantation.

    Science.gov (United States)

    Cabrera Fernández, D; Niazy, A M; Kurtz, R M; Djotyan, G P; Juhasz, T

    2006-03-01

    Refractive consequences of corneal transplants are analyzed using corneal biomechanical models assuming homogeneous and inhomogeneous stiffness distributions across the cornea. Additionally, refractive effects of grafts combined with volume removal procedures are also evaluated to develop methods to reduce postoperative refractive management of patients. Refinements of a two-dimensional finite element model are applied to simulate the biomechanical and refractive effects of different corneal transplant procedures: anterior lamellar keratoplasty, posterior lamellar keratoplasty, and penetrating keratoplasty. The models are based on a nonlinearly elastic, isotropic formulation. Predictions are compared with published clinical data. The model simulating the penetrating keratoplasty procedure predicts more change in the postoperative corneal curvature than models simulating anterior lamellar keratoplasty or posterior lamellar keratoplasty procedures. When a lenticle-shaped tissue with a central thickness of 50 microns and a diameter of 4 mm is removed from the anterior corneal surface along with the anterior lamellar keratoplasty or posterior lamellar keratoplasty, the models predict a refractive correction of -8.6 and -8.9 diopters, respectively. Simulations indicate that a posterior lamellar keratoplasty procedure is preferable for obtaining a better corneal curvature profile, eliminating the need for specific secondary treatments.

  11. Paradigm shifts in corneal transplantation.

    Science.gov (United States)

    Tan, Donald T H; Anshu, Arundhati; Mehta, Jodhbir S

    2009-04-01

    Conventional corneal transplantation, in the form of penetrating keratoplasty (PK), involves full-thickness replacement of the cornea, and is a highly successful procedure. However, the cornea is anatomically a multi-layered structure. Pathology may only affect individual layers of the cornea, hence selective lamellar surgical replacement of only the diseased corneal layers whilst retaining unaffected layers represents a new paradigm shift in the field. Recent advancements in surgical techniques and instrumentation have resulted in several forms of manual, microkeratome and femto-second laser-assisted lamellar transplantation procedures. Anterior lamellar keratoplasty (ALK) aims at replacing only diseased or scarred corneal stroma, whilst retaining the unaffected corneal endothelial layer, thus obviating the risk of endothelial allograft rejection. Posterior lamellar keratoplasty/endothelial keratoplasty (PLK/EK) involves the replacement of the dysfunctional endothelial cell layer only. Whilst significant technical and surgical challenges are involved in performing lamellar micro-dissection of a tissue which is only 0.5 mm thick, the benefits of a more controlled surgical procedure and improved graft survival rates have resulted in a shift away from conventional PK. This review details the current advances in emerging lamellar corneal surgical procedures and highlights the main advantages and disadvantages of these new lamellar corneal procedures.

  12. Corneal topography in cataract surgery.

    Science.gov (United States)

    Martinez, C E; Klyce, S D

    1996-02-01

    Keratometry and corneal topography remain the most important means of evaluating induced corneal changes after surgery and have comparable sensitivities in the paracentral region of the cornea. However, keratometry gives no information about the peripheral cornea or about asymmetry of the cornea. Videokeratography should be performed after cataract surgery in cases in which best-corrected visual acuity is not adequate and there are no other obvious causes for poor vision to determine whether corneal irregularities are present. The recent literature on corneal topographic evaluation of induced astigmatism after cataract surgery suggests that in general, smaller, temporal incisions result in less astigmatism. Preoperatively, corneal topography can be used in the calculation of intraocular lens power as well as incision planning. Postoperatively, it can be used to detect tight sutures, torsion of the wound, internal wound gape, and irregular astigmatism, as well as to guide suture removal. In the future, corneal topography will become increasingly important in the determination of intraocular lens power in difficult cases such as patients undergoing combined cataract extraction and penetrating keratoplasty as well as patients with a history of radial keratotomy or photorefractive surgery.

  13. CONTACT LENS RELATED CORNEAL ULCER

    Directory of Open Access Journals (Sweden)

    AGARWAL P

    2010-01-01

    Full Text Available A corneal ulcer caused by infection is one of the major causes of blindness worldwide. One of the recent health concerns is the increasing incidence of corneal ulcers associated with contact lens user especially if the users fail to follow specific instruction in using their contact lenses. Risk factors associated with increased risk of contact lens related corneal ulcers are:overnight wear, long duration of continuous wear, lower socio-economic classes, smoking, dry eye and poor hygiene. The presenting symptoms of contact lens related corneal ulcers include eye discomfort, foreign body sensation and lacrimation. More serious symptoms are redness (especially circum-corneal injection, severe pain, photophobia, eye discharge and blurring of vision. The diagnosis is established by a thorough slit lamp microscopic examination with fluorescein staining and corneal scraping for Gram stain and culture of the infective organism. Delay in diagnosing and treatment can cause permanent blindness, therefore an early referral to ophthalmologist and commencing of antimicrobial therapy can prevent visual loss.

  14. Anti-angiogenic effect of triptolide in rheumatoid arthritis by targeting angiogenic cascade.

    Directory of Open Access Journals (Sweden)

    Xiangying Kong

    Full Text Available Rheumatoid arthritis (RA is characterized by a pre-vascular seriously inflammatory phase, followed by a vascular phase with high increase in vessel growth. Since angiogenesis has been considered as an essential event in perpetuating inflammatory and immune responses, as well as supporting pannus growth and development of RA, inhibition of angiogenesis has been proposed as a novel therapeutic strategy for RA. Triptolide, a diterpenoid triepoxide from Tripterygium wilfordii Hook F, has been extensively used in treatment of RA patients. It also acts as a small molecule inhibitor of tumor angiogenesis in several cancer types. However, it is unclear whether triptolide possesses an anti-angiogenic effect in RA. To address this problem, we constructed collagen-induced arthritis (CIA model using DA rats by the injection of bovine type II collagen. Then, CIA rats were treated with triptolide (11-45 µg/kg/day starting on the day 1 after first immunization. The arthritis scores (P<0.05 and the arthritis incidence (P<0.05 of inflamed joints were both significantly decreased in triptolide-treated CIA rats compared to vehicle CIA rats. More interestingly, doses of 11~45 µg/kg triptolide could markedly reduce the capillaries, small, medium and large vessel density in synovial membrane tissues of inflamed joints (all P<0.05. Moreover, triptolide inhibited matrigel-induced cell adhesion of HFLS-RA and HUVEC. It also disrupted tube formation of HUVEC on matrigel and suppressed the VEGF-induced chemotactic migration of HFLS-RA and HUVEC, respectively. Furthermore, triptolide significantly reduced the expression of angiogenic activators including TNF-α, IL-17, VEGF, VEGFR, Ang-1, Ang-2 and Tie2, as well as suppressed the IL1-β-induced phosphorylated of ERK, p38 and JNK at protein levels. In conclusion, our data suggest for the first time that triptolide may possess anti-angiogenic effect in RA both in vivo and in vitro assay systems by downregulating the

  15. Acute pyelonephritis during pregnancy changes the balance of angiogenic and anti-angiogenic factors in maternal plasma.

    Science.gov (United States)

    Chaiworapongsa, Tinnakorn; Romero, Roberto; Gotsch, Francesca; Kusanovic, Juan Pedro; Mittal, Pooja; Kim, Sun Kwon; Erez, Offer; Vaisbuch, Edi; Mazaki-Tovi, Shali; Kim, Chong Jai; Dong, Zhong; Yeo, Lami; Hassan, Sonia S

    2010-02-01

    Angiogenic factors have been implicated in the pathophysiology of sepsis. In experimental models of sepsis (endotoxemia and/or cecal ligation puncture), there is increased expression of vascular endothelial growth factors (VEGF) and the administration of exogenous soluble VEGF receptor (sVEGFR)-1, an antagonist to VEGF, reduces morbidity and mortality. Moreover, a dramatic elevation in sVEGFR-1 has been demonstrated in human sepsis. Although a balance between angiogenic and anti-angiogenic factors is essential for feto-placental development, the changes of angiogenic factors during pregnancy in the context of infection have never been explored. Angiogenic factors also play crucial roles in the pathophysiology of preeclampsia (PE). This study was conducted to determine if maternal plasma concentrations of placental growth factor (PlGF), sVEGFR-2, and soluble endoglin (sEng) change in pregnancies complicated by acute pyelonephritis (AP) compared with normal pregnancy and PE. A case-control study was conducted in patients with AP, normal pregnant (NP) women, and patients with PE (n=36 for each group) matched for gestational age. AP was diagnosed in the presence of fever (temperature >or=38 degrees C), clinical signs of infection, and a positive urine culture for microorganisms. Plasma concentrations of PlGF, sVEGFR-2, and sEng were determined by ELISA. The results of plasma sVEGFR-1 concentrations have previously been reported, but were included in this study to provide a complete picture of the angiogenic/anti-angiogenic profiles. Serum concentrations of interleukin (IL)-1beta, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12p70, IL-13, interferon (IFN)-gamma, granulocyte macrophage colony stimulating factor, and tumor necrosis factor (TNF) were also determined using high sensitivity multiplexed immunoassays in patients with AP and NP. AP was associated with a lower median plasma concentration of PlGF and sVEGFR-2 than NP (both pIL-7, IL-8, IL-10, IFN-gamma, and TNF

  16. Angiogenic Factors and Cytokines in Diabetic Retinopathy

    Science.gov (United States)

    Abcouwer, Steven F.

    2013-01-01

    Diabetic retinopathy (DR) is a sight-threatening complication of both type-1 and type-2 diabetes. The recent success of treatments inhibiting the function of vascular endothelial growth factor (VEGF) demonstrates that specific targeting of a growth factor responsible for vascular permeability and growth is an effective means of treating DR-associated vascular dysfunction, edema and angiogenesis. This has stimulated research of alternative therapeutic targets involved in the control of retinal vascular function. However, additional treatment options and preventative measures are still needed and these require a greater understanding of the pathological mechanisms leading to the disturbance of retinal tissue homeostasis in DR. Although severe DR can be treated as a vascular disease, abundant data suggests that inflammation is also occurring in the diabetic retina.Thus, anti-inflammatory therapies may also be useful for treatment and prevention of DR. Herein, the evidence for altered expression of angiogenic factors and cytokines in DR is reviewed and possible mechanisms by which the expression of VEGF and cytokines may be increased in the diabetic retina are examined. In addition, the potential role for microglial activation in diabetic retinal neuroinflammation is explored. PMID:24319628

  17. Corneal wound healing after excimer laser keratectomy.

    Science.gov (United States)

    Kaji, Yuichi; Yamashita, Hidetoshi; Oshika, Tetsuro

    2003-03-01

    Excimer laser keratectomy is widely used to correct refractive errors. Several complications of excimer laser keratectomy are reported including corneal infection, regression, corneal haze formation, glare and halo. Most of the complications are closely related to the corneal stromal wound healing process. In order to perform the excimer laser keratectomy with minimum complications, we should understand the mechanism of the corneal stroma wound healing process. In addition, such knowledge will help us to regulate the corneal stromal wound healing process in the future. In the present article, we discuss the molecular mechanism of the corneal stromal wound healing process after excimer laser keratectomy and its regulation by anti-inflammatory agents.

  18. Immune privilege of the eye and fetus: parallel universes?

    Science.gov (United States)

    Niederkorn, Jerry Y; Wang, Shixuan

    2005-11-15

    The eye is an extension of the brain and thus many of its tissues are incapable of regeneration. Ocular inflammation can produce extensive damage to innocent bystander cells leading to blindness. However, the eye possesses multiple strategies to control immune-mediated inflammation-a phenomenon known as immune privilege. The fetus of outbred mammals expresses paternal histocompatibility antigens and represents an allograft. However, the success of placental animals is a testament to the immune privilege of the allogeneic fetus. Extensive evidence suggests that the eye and the fetus employ similar strategies for establishing immune privilege for preserving vision and the unborn respectively.

  19. White privilege, color blindness, and services to battered women.

    Science.gov (United States)

    Donnelly, Denise A; Cook, Kimberly J; van Ausdale, Debra; Foley, Lara

    2005-01-01

    White privilege is a system of benefits, advantages, and opportunities experienced by White persons in our society simply because of their skin color. In this article, the authors present the results of a descriptive, exploratory study of White privilege in battered women's shelters in the Deep South. Based on a qualitative analysis, the authors show how White privilege is intricately connected to executive directors' claims of color blindness, the othering of women of color, and viewing White as the norm. The authors conclude the article with implications for service provision to battered women and directions for future research.

  20. Corneal thickness changes after corneal collagen crosslinking for keratoconus and corneal ectasia: one-year results.

    Science.gov (United States)

    Greenstein, Steven A; Shah, Vinnie P; Fry, Kristen L; Hersh, Peter S

    2011-04-01

    To determine the changes in corneal thickness over time after corneal collagen crosslinking (CXL) for keratoconus and corneal ectasia. Cornea and refractive surgery subspecialty practice. Prospective randomized controlled clinical trial. Corneal thickness at the apex, thinnest point, and pupil center were measured using Scheimpflug imaging (Pentacam) at baseline and 1, 3, 6, and 12 months after CXL. The treatment group was compared with both a sham-procedure control group and a fellow-eye control group. Associations with clinical outcomes (uncorrected and corrected distance visual acuities and maximum keratometry) were analyzed. The study comprised 82 eyes, 54 with keratoconus and 28 with ectasia after laser in situ keratomileusis. The mean preoperative thinnest pachymetry was 440.7 μm ± 52.9 (SD). After CXL, the cornea thinned at 1 month (mean change -23.8 ± 28.7 μm; Pdegree of corneal thinning at 3 months and clinical outcomes after CXL. After CXL, the cornea thins and then recovers toward baseline thickness. The cause and implications of corneal thickness changes after CXL remain to be elucidated. No author has a financial or proprietary interest in any material or method mentioned. Additional disclosure is found in the footnotes. Copyright © 2011 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  1. Corneal stromal dystrophies: a clinical pathologic study

    Directory of Open Access Journals (Sweden)

    Elvira Barbosa Abreu

    2012-12-01

    Full Text Available INTRODUCTION: Corneal dystrophy is defined as bilateral and symmetric primary corneal disease, without previous associated ocular inflammation. Corneal dystrophies are classified according to the involved corneal layer in superficial, stromal, and posterior dystrophy. Incidence of each dystrophy varies according to the geographic region studied. PURPOSE: To evaluate the prevalence of stromal corneal dystrophies among corneal buttons specimens obtained by penetrating keratoplasty (PK in an ocular pathology laboratory and to correlate the diagnosis with patient age and gender. METHODS: Corneal button cases of penetrating keratoplasty from January-1996 to May-2009 were retrieved from the archives of The Henry C. Witelson Ophthalmic Pathology Laboratory and Registry, Montreal, Canada. The cases with histopathological diagnosis of stromal corneal dystrophies were stained with special stains (Peroxid acid Schiff, Masson trichrome, Congo red analyzed under polarized light, and alcian blue for classification and correlated with epidemiological information (age at time of PK and gender from patients' file. RESULTS: 1,300 corneal buttons cases with clinical diagnose of corneal dystrophy were retrieved. Stromal corneal dystrophy was found in 40 (3.1% cases. Lattice corneal dystrophy was the most prevalent with 26 cases (65%. Nineteen were female (73.07% and the PK was performed at average age of 59.3 years old. Combined corneal dystrophy was found in 8 (20% cases, 5 (62.5% of them were female and the average age of the penetrating keratoplasty was 54.8 years old. Granular corneal dystrophy was represented by 5 (12.5% cases, and 2 (40% of them were female. Penetrating keratoplasty was performed at average age of 39.5 years old in granular corneal dystrophy cases. Macular corneal dystrophy was present in only 1 (2.5% case, in a 36 years old female. CONCLUSION: Systematic histopathological approach and evaluation, including special stains in all stromal

  2. Corneal Sparing Conjunctival Abrasion

    Directory of Open Access Journals (Sweden)

    Hamid Ehsani-Nia

    2017-07-01

    Full Text Available History of present illness: A 15-year-old male was transported to the emergency department via ambulance as a trauma activation after being struck by an automobile while jogging. Patient was alert and oriented, with no focal neurological deficits and no loss of consciousness. The patient complained of right eye foreign body sensation. Significant findings: Physical exam was significant for multiple broken teeth, multiple minor abrasions on the face, and fine shards of shattered glass on his face and hair. His right eye had conjunctival injection, with no signs of subconjunctival hemorrhage or ocular penetration. Vision, extraocular movement, and pupillary exam were grossly intact. Fluorescein staining with slit lamp exam with cobalt blue filter examination of the right eye revealed superficial bulbar conjunctival uptake of fluorescein dye staining an area of the conjunctiva inferior to the limbus 5 mm vertical by 2 mm horizontal (estimation by photo provided. No foreign bodies were visualized in the inferior fornix. These findings were consistent with superficial conjunctival abrasion. The exam noted sparing of the corneal epithelium. Discussion: The conjunctiva is a thin, transparent membrane covering the ocular surface from the corneal limbus to the posterior eyelid margin.1 When damaged, the patient will classically have a “foreign body” sensation. It is important to identify the extent of the injury as not extending over the cornea, and also to search for lodged foreign bodies that damage the conjunctiva further with each blink. Classically retained foreign bodies will form a linear and vertical pattern of staining with fluorescein.2,3 Fluorescein stains expose basement membrane and fluoresces bright green under ultraviolet light, thus indicating areas of damage in contrast to its surrounding tissue.4,5 In the setting of acute trauma, urgent Ophthalmologic consultation is indicated if there is anterior chamber hemorrhage, a ruptured or

  3. Central corneal thickness and corneal hysteresis associated with glaucoma damage.

    Science.gov (United States)

    Congdon, Nathan G; Broman, Aimee T; Bandeen-Roche, Karen; Grover, Davinder; Quigley, Harry A

    2006-05-01

    We sought to measure the impact of central corneal thickness (CCT), a possible risk factor for glaucoma damage, and corneal hysteresis, a proposed measure of corneal resistance to deformation, on various indicators of glaucoma damage. Observational study. Adult patients of the Wilmer Glaucoma Service underwent measurement of hysteresis on the Reichert Ocular Response Analyzer and measurement of CCT by ultrasonic pachymetry. Two glaucoma specialists (H.A.Q., N.G.C.) reviewed the chart to determine highest known intraocular pressure (IOP), target IOP, diagnosis, years with glaucoma, cup-to-disk ratio (CDR), mean defect (MD), pattern standard deviation (PSD), glaucoma hemifield test (GHT), and presence or absence of visual field progression. Among 230 subjects, the mean age was 65 +/- 14 years, 127 (55%) were female, 161 (70%) were white, and 194 (85%) had a diagnosis of primary open-angle glaucoma (POAG) or suspected POAG. In multivariate generalized estimating equation models, lower corneal hysteresis value (P = .03), but not CCT, was associated with visual field progression. When axial length was included in the model, hysteresis was not a significant risk factor (P = .09). A thinner CCT (P = .02), but not hysteresis, was associated with a higher CDR at the most recent examination. Neither CCT nor hysteresis was associated with MD, PSD, or GHT "outside normal limits." Thinner CCT was associated with the state of glaucoma damage as indicated by CDR. Axial length and corneal hysteresis were associated with progressive field worsening.

  4. Liberal luxury: Decentering Snowden, surveillance and privilege

    Directory of Open Access Journals (Sweden)

    Piro Rexhepi

    2016-11-01

    Full Text Available This paper reflects on the continued potency of veillance theories to traverse beyond the taxonomies of surveillance inside liberal democracies. It provides a commentary on the ability of sousveillance to destabilise and disrupt suer/violence by shifting its focus from the centre to the periphery, where Big Data surveillance is tantamount to sur/violence. In these peripheral political spaces, surveillance is not framed by concerns over privacy, democracy and civil society; rather, it is a matter of life and death, a technique of both biopolitical and thanatopolitical power. I argue that the universalist, and universalizing, debates over surveillance cannot be mapped through the anxieties of privileged middle classes as they would neither transcend nor make possible alternative ways of tackling the intersection of surveillance and violence so long as they are couched in the liberal concerns for democracy. I call this phenomenon “liberal luxury,” whereby debates over surveillance have over-emphasised liberal proclivities at the expense of disengaging those peripheral populations most severely affected by sur/violence.

  5. Substrates for Expansion of Corneal Endothelial Cells towards Bioengineering of Human Corneal Endothelium

    Directory of Open Access Journals (Sweden)

    Jesintha Navaratnam

    2015-09-01

    Full Text Available Corneal endothelium is a single layer of specialized cells that lines the posterior surface of cornea and maintains corneal hydration and corneal transparency essential for vision. Currently, transplantation is the only therapeutic option for diseases affecting the corneal endothelium. Transplantation of corneal endothelium, called endothelial keratoplasty, is widely used for corneal endothelial diseases. However, corneal transplantation is limited by global donor shortage. Therefore, there is a need to overcome the deficiency of sufficient donor corneal tissue. New approaches are being explored to engineer corneal tissues such that sufficient amount of corneal endothelium becomes available to offset the present shortage of functional cornea. Although human corneal endothelial cells have limited proliferative capacity in vivo, several laboratories have been successful in in vitro expansion of human corneal endothelial cells. Here we provide a comprehensive analysis of different substrates employed for in vitro cultivation of human corneal endothelial cells. Advances and emerging challenges with ex vivo cultured corneal endothelial layer for the ultimate goal of therapeutic replacement of dysfunctional corneal endothelium in humans with functional corneal endothelium are also presented.

  6. Unpacking the invisible knapsack: The invention of white privilege pedagogy

    National Research Council Canada - National Science Library

    Margolin, Leslie

    2015-01-01

    ..., in particular their foundational technique, "unpacking the invisible knapsack." This article's chief finding is that this pedagogy, though designed to fight racism, has the unintended effect of supporting white privilege...

  7. Unpacking the invisible knapsack: The invention of white privilege pedagogy

    Directory of Open Access Journals (Sweden)

    Leslie Margolin

    2015-12-01

    Full Text Available This article uses Ricoeur’s hermeneutics of suspicion, an interpretive strategy directed to the hidden or repressed meanings behind texts, to examine the origins of white privilege pedagogy, in particular their foundational technique, “unpacking the invisible knapsack.” This article’s chief finding is that this pedagogy, though designed to fight racism, has the unintended effect of supporting white privilege. Teaching whites to “unpack their invisible knapsack” does not make them more willing to take action against racial inequality. On the contrary, it makes them more complacent, more at home in an unjust world, and more comfortable with their whiteness. White privilege pedagogy does this by focusing on personal identity (whites’ personal identity over institutional structures, by paying more attention to whites’ experiences than to blacks’, by falsely claiming that the confession of white privileges leads to social action beneficial to blacks, and by restoring and expanding whites’ sense of moral rightness.

  8. Quiste dermoide corneal bilateral

    Directory of Open Access Journals (Sweden)

    Michel Guerra Almaguer

    Full Text Available El dermoide es un tipo de coristoma (tejido embrionario normal en una localización anormal que afecta con frecuencia la córnea. Aparece como una masa sólida, blanca, redonda y elevada. Suele localizarse en el limbo inferotemporal, aunque puede hacerlo en cualquier lugar del globo ocular o de la órbita. Se presenta un paciente masculino, de 8 años de edad, quien desde su nacimiento muestra una mancha blanca en ambos ojos, agudeza visual sin corrección de movimiento de mano a 33 centímetros en el ojo derecho y percepción luminosa en el ojo izquierdo. En la exploración oftalmológica de ambos ojos se apreciaron lesiones blanquecinas sobre la córnea. Se le realizó exéresis del quiste y queratoplastia lamelar de ambos ojos, con resultados visuales satisfactorios. Se concluye que el caso presenta un quiste dermoide corneal bilateral.

  9. Corneal biomechanics: a review.

    Science.gov (United States)

    Piñero, David P; Alcón, Natividad

    2015-03-01

    Biomechanics is often defined as 'mechanics applied to biology'. Due to the variety and complexity of the behaviour of biological structures and materials, biomechanics is better defined as the development, extension and application of mechanics for a better understanding of physiology and physiopathology and consequently for a better diagnosis and treatment of disease and injury. Different methods for the characterisation of corneal biomechanics are reviewed in detail, including those that are currently commercially available (Ocular Response Analyzer and CorVis ST). The clinical applicability of the parameters provided by these devices are discussed, especially in the fields of glaucoma, detection of ectatic disorders and orthokeratology. Likewise, other methods are also reviewed, such as Brillouin microscopy or dynamic optical coherence tomography and others with potential application to clinical practice but not validated for in vivo measurements, such as ultrasonic elastography. Advantages and disadvantages of all these techniques are described. Finally, the concept of biomechanical modelling is revised as well as the requirements for developing biomechanical models, with special emphasis on finite element modelling. © 2014 The Authors. Clinical and Experimental Optometry © 2014 Optometry Australia.

  10. 42 CFR 3.204 - Privilege of patient safety work product.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Privilege of patient safety work product. 3.204... PROVISIONS PATIENT SAFETY ORGANIZATIONS AND PATIENT SAFETY WORK PRODUCT Confidentiality and Privilege Protections of Patient Safety Work Product § 3.204 Privilege of patient safety work product. (a) Privilege...

  11. Intersectional perspectives on intimate technology, solutionism, and privilege

    DEFF Research Database (Denmark)

    Søndergaard, Marie Louise Juul; Hansen, Lone Koefoed

    In this text, we discuss if and how an intersectional perspective on design may be critically practiced from a privileged position. More precisely, we ask how intersectional perspectives on race, gender and class may be useful in reflecting on and critically intervening in a privileged, Northern...... European culture. Our discussion is motivated by considerations into what impact culture and context have on the practice, representation, and reception of critique....

  12. Internal investigations and the evolving fate of privilege

    OpenAIRE

    Dervan, Lucian E.

    2016-01-01

    In 1981, the United States Supreme Court delivered a landmark ruling in Upjohn Co. v. United States. The decision made clear that the protections afforded by the attorneyclient privilege apply to internal corporate investigations. This piece examines the fundamental tenets of Upjohn, discusses some recent challenges to the applicability of privilege to materials gathered during internal investigations, and considers the manner in which the international nature of modern internal investigat...

  13. Femtosecond laser corneal refractive surgery

    Science.gov (United States)

    Kurtz, Ron M.; Spooner, Greg J. R.; Sletten, Karin R.; Yen, Kimberly G.; Sayegh, Samir I.; Loesel, Frieder H.; Horvath, Christopher; Liu, HsiaoHua; Elner, Victor; Cabrera, Delia; Muenier, Marie-Helene; Sacks, Zachary S.; Juhasz, Tibor

    1999-06-01

    We evaluated the efficacy, safety, and stability of femtosecond laser intrastromal refractive procedures in ex vivo and in vivo models. When compared with longer pulsewidth nanosecond or picosecond laser pulses, femtosecond laser-tissue interactions are characterized by significantly smaller and more deterministic photodisruptive energy thresholds, as well as reduced shock waves and smaller cavitation bubbles. We utilized a highly reliable, all-solid-state femtosecond laser system for all studies to demonstrate clinical practicality. Contiguous tissue effects were achieved by scanning a 5 μm focused laser spot below the corneal surface at pulse energies of approximately 2 - 4 microjoules. A variety of scanning patterns was used to perform three prototype procedures in animal eyes; corneal flap cutting, keratomileusis, and intrastromal vision correction. Superior dissection and surface quality results were obtained for lamellar procedures (corneal flap cutting and keratomileusis). Preliminary in vivo evaluation of intrastromal vision correction in a rabbit model revealed consistent and stable pachymetry changes, without significant inflammation or loss of corneal transparency. We conclude that femtosecond laser technology may be able to perform a variety of corneal refractive procedures with high precision, offering advantages over current mechanical and laser devices and techniques.

  14. Corneal complications of vernal keratoconjunctivitis.

    Science.gov (United States)

    Solomon, Abraham

    2015-10-01

    Vernal keratoconjunctivitis (VKC) is a severe bilateral chronic allergic inflammatory disease of the ocular surface. In most of the cases, the disease is limited to the tarsal conjunctiva and to the limbus. However, in the more severe cases, the cornea may be involved, leading to potentially sight threatening complications. Prompt recognition of these complications is crucial in the management of VKC, which is one of the most severe ocular allergic diseases. A vicious cycle of inflammation occurs as a result of a set of reciprocal interactions between the conjunctiva and the cornea, which results in damage to the corneal epithelium and corneal stoma, and to the formation of shield ulcers and plaques, infectious keratitis, keratoconus, scarring, and limbal stem cell deficiency. These corneal complications can cause permanent decrease or loss of vision in children suffering from VKC. Corneal complications in VKC are the result of an on-going process of uncontrolled inflammation. Proper recognition of the corneal complications in VKC is crucial, as most of these can be managed or prevented by a combination of medical and surgical measures.

  15. An accessible approach for corneal topography

    OpenAIRE

    André Luís Beling da Rosa

    2013-01-01

    Corneal topography consists of measuring the corneal shape, which is a key factor for visual acuity. The exam is used, for instance, in keratoconus detection, personalized contact lens fitting, in pre- and post-procedures associated with refractive surgery and corneal transplants. This thesis presents an accessible, inexpensive and portable approach to perform corneal topographies. The results obtained with our prototype show a mean difference of about 0.02 millimeters, equivalent to 0.5% of ...

  16. Friends Turned Foes: Angiogenic Growth Factors beyond Angiogenesis

    Directory of Open Access Journals (Sweden)

    Pratiek N. Matkar

    2017-10-01

    Full Text Available Angiogenesis, the formation of new blood vessels from pre-existing ones is a biological process that ensures an adequate blood flow is maintained to provide the cells with a sufficient supply of nutrients and oxygen within the body. Numerous soluble growth factors and inhibitors, cytokines, proteases as well as extracellular matrix proteins and adhesion molecules stringently regulate the multi-factorial process of angiogenesis. The properties and interactions of key angiogenic molecules such as vascular endothelial growth factors (VEGFs, fibroblast growth factors (FGFs and angiopoietins have been investigated in great detail with respect to their molecular impact on angiogenesis. Since the discovery of angiogenic growth factors, much research has been focused on their biological actions and their potential use as therapeutic targets for angiogenic or anti-angiogenic strategies in a context-dependent manner depending on the pathologies. It is generally accepted that these factors play an indispensable role in angiogenesis. However, it is becoming increasingly evident that this is not their only role and it is likely that the angiogenic factors have important functions in a wider range of biological and pathological processes. The additional roles played by these molecules in numerous pathologies and biological processes beyond angiogenesis are discussed in this review.

  17. Progress of research on corneal collagen cross-linking for corneal melting

    Directory of Open Access Journals (Sweden)

    Ke-Ren Xiao

    2016-06-01

    Full Text Available Corneal collagen cross-linking(CXLcould increase the mechanical strength, biological stability and halt ectasia progression due to covalent bond formed by photochemical reaction between ultraviolet-A and emulsion of riboflavin between collagen fibers in corneal stroma. Corneal melting is an autoimmune related noninfectious corneal ulcer. The mechanism of corneal melting, major treatment, the basic fundamental of ultraviolet-A riboflavin induced CXL and the clinical researches status and experiment in CXL were summarized in the study.

  18. Ocular dimensions, corneal thickness, and corneal curvature in quarter horses with hereditary equine regional dermal asthenia.

    Science.gov (United States)

    Badial, Peres R; Cisneros-Àlvarez, Luis Emiliano; Brandão, Cláudia Valéria S; Ranzani, José Joaquim T; Tomaz, Mayana A R V; Machado, Vania M; Borges, Alexandre S

    2015-09-01

    The aim of this study was to compare ocular dimensions, corneal curvature, and corneal thickness between horses affected with hereditary equine regional dermal asthenia (HERDA) and unaffected horses. Five HERDA-affected quarter horses and five healthy control quarter horses were used. Schirmer's tear test, tonometry, and corneal diameter measurements were performed in both eyes of all horses prior to ophthalmologic examinations. Ultrasonic pachymetry was performed to measure the central, temporal, nasal, dorsal, and ventral corneal thicknesses in all horses. B-mode ultrasound scanning was performed on both eyes of each horse to determine the dimensions of the ocular structures and to calculate the corneal curvature. Each corneal region examined in this study was thinner in the affected group compared with the healthy control group. However, significant differences in corneal thickness were only observed for the central and dorsal regions. HERDA-affected horses exhibited significant increases in corneal curvature and corneal diameter compared with unaffected animals. The ophthalmologic examinations revealed mild corneal opacity in one eye of one affected horse and in both eyes of three affected horses. No significant between-group differences were observed for Schirmer's tear test, intraocular pressure, or ocular dimensions. Hereditary equine regional dermal asthenia-affected horses exhibit decreased corneal thickness in several regions of the cornea, increased corneal curvature, increased corneal diameter, and mild corneal opacity. Additional research is required to determine whether the increased corneal curvature significantly impacts the visual accuracy of horses with HERDA. © 2014 American College of Veterinary Ophthalmologists.

  19. Acute corneal hydrops in keratoconus

    Directory of Open Access Journals (Sweden)

    Prafulla K Maharana

    2013-01-01

    Full Text Available Acute corneal hydrops is a condition characterized by stromal edema due to leakage of aqueous through a tear in descemet membrane. The patient presents with sudden onset decrease in vision, photophobia, and pain. Corneal thinning and ectasias combined with trivial trauma to the eye mostly by eye rubbing is considered as the underlying cause. With conservative approach self-resolution takes around 2 to 3 months. Surgical intervention is required in cases of non-resolution of corneal edema to avoid complications and for early visual rehabilitation. Intracameral injection of air or gas such as perflouropropane is the most common surgical procedure done. Recent investigative modality such as anterior segment optical coherence tomography is an extremely useful tool for diagnosis, surgical planning, and postoperative follow up. Resolution of hydrops may improve the contact lens tolerance and visual acuity but most cases require keratoplasty for visual rehabilitation.

  20. [Corneal toxicity due to amantadine].

    Science.gov (United States)

    Avendaño-Cantos, E M; Celis-Sánchez, J; Mesa-Varona, D; Gálvez-Martínez, J; López-Arroquia, E; González Del Valle, F

    2012-09-01

    A 64 year-old female with Parkinson disease treated with amantadine for two years who suddenly suffered bilateral corneal oedema. It was initially treated as herpetic endotheliitis without improvement as we lacked information on her chronic treatment. The corneal oedema finally resolved after withdrawing the drug. Amantadine hydrochloride may produce endothelial dysfunction. Once the amantadine treatment is stopped, the corneal oedema may be reversible but endothelial density remains low. An ophthalmologist examination should be performed before the initiation of amantadine treatment in order to establish a risk: benefit ratio, especially in those patients with low endothelial density or any endothelial anomaly. Copyright © 2011 Sociedad Española de Oftalmología. Published by Elsevier Espana. All rights reserved.

  1. Affective privilege: Asymmetric interference by emotional distracters

    Directory of Open Access Journals (Sweden)

    Crystal eReeck

    2011-09-01

    Full Text Available Numerous theories posit that affectively salient stimuli are privileged in their capacity to capture attention and disrupt ongoing cognition. Two underlying assumptions in this theoretical position are that the potency of affective stimuli transcends task boundaries (i.e., emotional distracters do not have to belong to a current task-set to disrupt processing and that there is an asymmetry between emotional and cognitive processing (i.e., emotional distracters disrupt cognitive processing, but not vice versa. These assumptions have remained largely untested, as common experimental probes of emotion-cognition interaction rarely manipulate task-relevance and only examine one side of the presumed asymmetry of interference. To test these propositions directly, a face-word Stroop protocol was adapted to independently manipulate (a the congruency between target and distracter stimulus features, (b the affective salience of distracter features, and (c the task-relevance of emotional compared to non-emotional target features. A three-way interaction revealed interdependent effects of distracter relevance, congruence, and affective salience. Compared to task-irrelevant distracters, task-relevant congruent distracters facilitated performance and task-relevant incongruent distracters impaired performance, but the latter effect depended on the nature of the target feature and task. Specifically, task-irrelevant emotional distracters resulted in equivalent performance costs as task-relevant non-emotional distracters, whereas task-irrelevant non-emotional distracters did not produce performance costs comparable to those generated by task-relevant emotional distracters. These results document asymmetric cross-task interference effects for affectively salient stimuli, supporting the notion of affective prioritization in human information processing.

  2. Posterior Corneal Surface Stability after Femtosecond Laser-Assisted Keratomileusis

    Directory of Open Access Journals (Sweden)

    Carlo Cagini

    2015-01-01

    Full Text Available The purpose of this study was to evaluate posterior corneal surface variation after femtosecond laser-assisted keratomileusis in patients with myopia and myopic astigmatism. Patients were evaluated by corneal tomography preoperatively and at 1, 6, and 12 months. We analyzed changes in the posterior corneal curvature, posterior corneal elevation, and anterior chamber depth. Moreover, we explored correlation between corneal ablation depth, residual corneal thickness, percentage of ablated corneal tissue, and preoperative corneal thickness. During follow-up, the posterior corneal surface did not have a significant forward corneal shift: no significant linear relationships emerged between the anterior displacement of the posterior corneal surface and corneal ablation depth, residual corneal thickness, or percentage of ablated corneal tissue.

  3. Progress in corneal wound healing

    Science.gov (United States)

    Ljubimov, Alexander V.; Saghizadeh, Mehrnoosh

    2015-01-01

    Corneal wound healing is a complex process involving cell death, migration, proliferation, differentiation, and extracellular matrix remodeling. Many similarities are observed in the healing processes of corneal epithelial, stromal and endothelial cells, as well as cell-specific differences. Corneal epithelial healing largely depends on limbal stem cells and remodeling of the basement membrane. During stromal healing, keratocytes get transformed to motile and contractile myofibroblasts largely due to activation of transforming growth factor-β system. Endothelial cells heal mostly by migration and spreading, with cell proliferation playing a secondary role. In the last decade, many aspects of wound healing process in different parts of the cornea have been elucidated, and some new therapeutic approaches have emerged. The concept of limbal stem cells received rigorous experimental corroboration, with new markers uncovered and new treatment options including gene and microRNA therapy tested in experimental systems. Transplantation of limbal stem cell-enriched cultures for efficient re-epithelialization in stem cell deficiency and corneal injuries has become reality in clinical setting. Mediators and course of events during stromal healing have been detailed, and new treatment regimens including gene (decorin) and stem cell therapy for excessive healing have been designed. This is a very important advance given the popularity of various refractive surgeries entailing stromal wound healing. Successful surgical ways of replacing the diseased endothelium have been clinically tested, and new approaches to accelerate endothelial healing and suppress endothelial-mesenchymal transformation have been proposed including Rho kinase (ROCK) inhibitor eye drops and gene therapy to activate TGF-β inhibitor SMAD7. Promising new technologies with potential for corneal wound healing manipulation including microRNA, induced pluripotent stem cells to generate corneal epithelium, and

  4. A novel nucleic acid analogue shows strong angiogenic activity

    Energy Technology Data Exchange (ETDEWEB)

    Tsukamoto, Ikuko, E-mail: tukamoto@med.kagawa-u.ac.jp [Department of Pharmaco-Bio-Informatics, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki, Kita, Kagawa 761-0793 (Japan); Sakakibara, Norikazu; Maruyama, Tokumi [Kagawa School of Pharmaceutical Sciences, Tokushima Bunri University, 1314-1 Shido, Sanuki, Kagawa 769-2193 (Japan); Igarashi, Junsuke; Kosaka, Hiroaki [Department of Cardiovascular Physiology, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki, Kita, Kagawa 761-0793 (Japan); Kubota, Yasuo [Department of Dermatology, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki, Kita, Kagawa 761-0793 (Japan); Tokuda, Masaaki [Department of Cell Physiology, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki, Kita, Kagawa 761-0793 (Japan); Ashino, Hiromi [The Tokyo Metropolitan Institute of Medical Science, 1-6 Kamikitazawa2-chome, Setagaya-ku, Tokyo 156-8506 (Japan); Hattori, Kenichi; Tanaka, Shinji; Kawata, Mitsuhiro [Teikoku Seiyaku Co., Ltd., Sanbonmatsu, Higashikagawa, Kagawa 769-2695 (Japan); Konishi, Ryoji [Department of Pharmaco-Bio-Informatics, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki, Kita, Kagawa 761-0793 (Japan)

    2010-09-03

    Research highlights: {yields} A novel nucleic acid analogue (2Cl-C.OXT-A, m.w. 284) showed angiogenic potency. {yields} It stimulated the tube formation, proliferation and migration of HUVEC in vitro. {yields} 2Cl-C.OXT-A induced the activation of ERK1/2 and MEK in HUVEC. {yields} Angiogenic potency in vivo was confirmed in CAM assay and rabbit cornea assay. {yields} A synthesized small angiogenic agent would have great clinical therapeutic value. -- Abstract: A novel nucleic acid analogue (2Cl-C.OXT-A) significantly stimulated tube formation of human umbilical endothelial cells (HUVEC). Its maximum potency at 100 {mu}M was stronger than that of vascular endothelial growth factor (VEGF), a positive control. At this concentration, 2Cl-C.OXT-A moderately stimulated proliferation as well as migration of HUVEC. To gain mechanistic insights how 2Cl-C.OXT-A promotes angiogenic responses in HUVEC, we performed immunoblot analyses using phospho-specific antibodies as probes. 2Cl-C.OXT-A induced robust phosphorylation/activation of MAP kinase ERK1/2 and an upstream MAP kinase kinase MEK. Conversely, a MEK inhibitor PD98059 abolished ERK1/2 activation and tube formation both enhanced by 2Cl-C.OXT-A. In contrast, MAP kinase responses elicited by 2Cl-C.OXT-A were not inhibited by SU5416, a specific inhibitor of VEGF receptor tyrosine kinase. Collectively these results suggest that 2Cl-C.OXT-A-induces angiogenic responses in HUVEC mediated by a MAP kinase cascade comprising MEK and ERK1/2, but independently of VEGF receptor tyrosine kinase. In vivo assay using chicken chorioallantoic membrane (CAM) and rabbit cornea also suggested the angiogenic potency of 2Cl-C.OXT-A.

  5. Leptin’s Pro-Angiogenic Signature in Breast Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Perez, Ruben Rene, E-mail: rgonzalez@msm.edu; Lanier, Viola; Newman, Gale [Department of Microbiology, Biochemistry and Immunology, Morehouse School of Medicine, 720 Westview Dr. SW., Atlanta, GA 30310 (United States)

    2013-09-06

    Obesity is linked to increased incidence of breast cancer. The precise causes and mechanisms of these morbid relationships are unknown. Contradictory data on leptin angiogenic actions have been published. However, accumulating evidence would suggest that leptin’s pro-angiogenic effects in cancer play an essential role in the disease. Leptin, the main adipokine secreted by adipose tissue, is also abnormally expressed together with its receptor (OB-R) by breast cancer cells. Leptin induces proliferation and angiogenic differentiation of endothelial cells upregulates VEGF/VEGFR2 and transactivates VEGFR2 independent of VEGF. Leptin induces two angiogenic factors: IL-1 and Notch that can increase VEGF expression. Additionally, leptin induces the secretion and synthesis of proteases and adhesion molecules needed for the development of angiogenesis. Leptin’s paracrine actions can further affect stromal cells and tumor associated macrophages, which express OB-R and secrete VEGF and IL-1, respectively. A complex crosstalk between leptin, Notch and IL-1 (NILCO) that induces VEGF/VEGFR2 is found in breast cancer. Leptin actions in tumor angiogenesis could amplify, be redundant and/or compensatory to VEGF signaling. Current failure of breast cancer anti-angiogenic therapies emphasizes the necessity of targeting the contribution of other pro-angiogenic factors in breast cancer. Leptin’s impact on tumor angiogenesis could be a novel target for breast cancer, especially in obese patients. However, more research is needed to establish the importance of leptin in tumor angiogenesis. This review is focused on updated information on how leptin could contribute to tumor angiogenesis.

  6. Progastrin a new pro-angiogenic factor in colorectal cancer.

    Science.gov (United States)

    Najib, S; Kowalski-Chauvel, A; Do, C; Roche, S; Cohen-Jonathan-Moyal, E; Seva, C

    2015-06-11

    Angiogenesis is essential in tumor progression and metastatic process, and increased angiogenesis has been associated with poor prognosis and relapse of colorectal cancer (CRC). VEGF has become the main target of anti-angiogenic therapy. However, most patients relapse after an initial response or present a resistance to the treatment. Identification of new pro-angiogenic factors may help to improve anti-angiogenic therapy. In this study, we demonstrated that the pro-hormone progastrin (PG), over-expressed in CRC, recognized as a growth factor, is a potent pro-angiogenic factor. In transgenic mice and human colorectal HPs producing high levels of PG, we correlated PG overexpression with an increased vascularization. In vitro, exogenous PG and conditioned media (CM) from CRC cells producing PG increased endothelial cell proliferation and migration. We also showed that treatment with exogenous PG can increase the ability of endothelial cells to form capillary-like structures. Moreover, we demonstrated that PG enhanced endothelial permeability. The finding that PG stimulated the phosphorylation of vascular endothelial (VE)-cadherin, p125-FAK, paxillin and induced actin remodelling was consistent with a role of these components in PG-stimulated endothelial cell migration and permeability. The pro-angiogenic effects observed with CM were significantly inhibited when CRC cells expressed a PG shRNA. In vivo, we found an important decrease in tumor growth and neovascularization when the CRC cells expressing the PG shRNA were xenografted in mice or in the chick chorioallantoic membrane model. We also observed an increase in the coverage of blood vessels by pericytes and a decrease in endothelial permeability when PG expression was blocked. Our results demonstrate that PG is a new pro-angiogenic factor in CRC and an attractive therapeutic target.

  7. Corneal Thickness as a Predictor of Corneal Transplant Outcome

    Science.gov (United States)

    Verdier, David D.; Sugar, Alan; Baratz, Keith; Beck, Roy; Dontchev, Mariya; Dunn, Steven; Gal, Robin L.; Holland, Edward J.; Kollman, Craig; Lass, Jonathan H.; Mannis, Mark J.; Penta, Jeffrey

    2013-01-01

    Purpose Assess corneal thickness (CT) and correlation with graft outcome after penetrating keratoplasty in the Cornea Donor Study. Methods 887 subjects with a corneal transplant for a moderate risk condition (principally Fuchs or pseudophakic corneal edema) had post-operative CT measurements throughout a 5 year follow up time. Relationships between baseline (recipient, donor, and operative) factors and CT were explored. Proportional hazards models were used to assess association between CT and graft failure. Relationship between CT and cell density was assessed with a longitudinal repeated measures model and Spearman correlation estimates. Results Higher longitudinal CT measurements were associated with diagnosis of pseudophakic or aphakic corneal edema (P 25mmHg during the first post-operative month (P=0.003), white (non-Hispanic) donor race (P=0.002) and respiratory causes of donor death (P600μm. In multivariate analysis, both 1 year CT and cell density were associated with subsequent graft failure (P=0.002 and 0.009). CT increase was modestly associated with endothelial cell loss during follow up (r=-0.29). Conclusion During the first 5 years following penetrating keratoplasty, CT can serve as a predictor of graft survival. However, CT is not a substitute for cell density measurement as both measures were independently predictive of graft failure. PMID:23343949

  8. Definition of the "Drug-Angiogenic-Activity-Index" that allows the quantification of the positive and negative angiogenic active drugs: a study based on the chorioallantoic membrane model.

    Science.gov (United States)

    Demir, Resit; Peros, Georgios; Hohenberger, Werner

    2011-06-01

    Since the introduction of the angiogenic therapy by Folkman et al. in the 1970'ies many antiangiogenic drugs were identified. Only few of them are still now in clinical use. Also the Vascular Endothelial Growth Factor (VEGF), the cytokine with the highest angiogenic activity, has been identified. Its antagonist, Bevacizumab, is produced and admitted for the angiogenic therapy in first line for metastatic colorectal cancer. When we look at preclinical studies, they fail of in vivo models that define the "Drug-Angiogenic-Activity-Index" of angiogenic or antiangiogenic drugs. This work proposes a possible standardized procedure to define the "Drug Angiogenic Activity Index" by counting the vascular intersections (VIS) on the Chorioallantoic Membrane after drug application. The equation was defined as follows: {ΔVIS[Drug]-ΔVIS[Control]} / Δ VIS[Control]. For VEGF a Drug-Angiogenic-Activity-Index of 0.92 was found and for Bevacizumab a -1. This means almost that double of the naturally angiogenic activity was achieved by VEGF on the Chorioallantoic membrane. A complete blocking of naturally angiogenic activity was observed after Bevacizumabs application. Establishing the "Drug-Angiogenic-Activity-Index" in the preclinical phase will give us an impact of effectiveness for the new constructed antiangiogenic drugs like the impact of effectiveness in the cortisone family.

  9. Metalloproteinases in corneal diseases: degradation and processing.

    Science.gov (United States)

    Sakimoto, Tohru; Sawa, Mitsuru

    2012-11-01

    Matrix metalloproteinases (MMPs) are zinc-dependent endopeptidases with the potential to degrade all types of extracellular matrix. The ADAM (a disintegrin and metalloproteinase) family of peptidases was recently identified as cleaving the extracellular domain of transmembrane proteins. This was termed ectodomain shedding. We investigated the MMP expression in patients with corneal diseases and the potential role of ADAMs in corneal pathophysiology. We detected upregulation of the active form of MMP-2 and MMP-9 in the tear fluid from patients with corneal melting or recurrent corneal erosion. Using human corneal epithelial cells, we observed ADAM17-dependent ectodomain shedding of soluble tumor necrosis factor receptor 1 and soluble interleukin-6 (IL-6) receptor (sIL-6R). The production of sIL-6R was also induced by messenger RNA splicing in the human corneal epithelial cells. IL-6/sIL-6R-induced signal transducer and activator of transcription 3 phosphorylation was observed in cultured human corneal fibroblasts, suggesting that IL-6 trans-signaling induced inflammatory cellular signaling in the human corneal fibroblasts. We demonstrated that MMPs are significantly upregulated in collagen-destructive disorders of the cornea. Additionally, we observed that ectodomain shedding by ADAMs in corneal epithelial cells mediated the production of soluble cytokine receptors. Trans-signaling of IL-6 can induce an inflammatory response in corneal stroma, indicating the significance of IL-6 trans-signaling in ocular surface inflammation. Thus, MMPs and ADAMs play an important role in the pathophysiology of corneal diseases.

  10. Corneal Regeneration After Photorefractive Keratectomy: A Review☆

    Science.gov (United States)

    Tomás-Juan, Javier; Murueta-Goyena Larrañaga, Ane; Hanneken, Ludger

    2014-01-01

    Photorefractive keratectomy (PRK) remodels corneal stroma to compensate refractive errors. The removal of epithelium and the ablation of stroma provoke the disruption of corneal nerves and a release of several peptides from tears, epithelium, stroma and nerves. A myriad of cytokines, growth factors, and matrix metalloproteases participate in the process of corneal wound healing. Their balance will determine if reepithelization and stromal remodeling are appropriate. The final aim is to achieve corneal transparency for restoring corneal function, and a proper visual quality. Therefore, wound-healing response is critical for a successful refractive surgery. Our goal is to provide an overview into how corneal wounding develops following PRK. We will also review the influence of intraoperative application of mitomycin C, bandage contact lenses, anti-inflammatory and other drugs in preventing corneal haze and post-PRK pain. PMID:25444646

  11. Corneal Regeneration After Photorefractive Keratectomy: A Review.

    Science.gov (United States)

    Tomás-Juan, Javier; Murueta-Goyena Larrañaga, Ane; Hanneken, Ludger

    2015-01-01

    Photorefractive keratectomy (PRK) remodels corneal stroma to compensate refractive errors. The removal of epithelium and the ablation of stroma provoke the disruption of corneal nerves and a release of several peptides from tears, epithelium, stroma and nerves. A myriad of cytokines, growth factors, and matrix metalloproteases participate in the process of corneal wound healing. Their balance will determine if reepithelization and stromal remodeling are appropriate. The final aim is to achieve corneal transparency for restoring corneal function, and a proper visual quality. Therefore, wound-healing response is critical for a successful refractive surgery. Our goal is to provide an overview into how corneal wounding develops following PRK. We will also review the influence of intraoperative application of mitomycin C, bandage contact lenses, anti-inflammatory and other drugs in preventing corneal haze and post-PRK pain. Copyright © 2014 Spanish General Council of Optometry. Published by Elsevier Espana. All rights reserved.

  12. History of corneal transplantation in Australia.

    Science.gov (United States)

    Coster, Douglas J

    2015-04-01

    Corneal transplantation is a triumph of modern ophthalmology. The possibility of corneal transplantation was first raised in 1797 but a century passed before Zirm achieved the first successful penetrating graft in 1905. Gibson reported the first corneal graft in Australia from Brisbane in 1940 and English established the first eye bank there a few years later. Corneal transplantation evolved steadily over the twentieth century. In the second half of the century, developments in microsurgery, including surgical materials such as monofilament nylon and strong topical steroid drops, accounted for improvements in outcomes. In 2013, approximately 1500 corneal transplants were done in Australia. Eye banking has evolved to cope with the rising demands for donor corneas. Australian corneal surgeons collaborated to establish and support the Australian Corneal Graft Registry in 1985. It follows the outcomes of their surgery and has become an important international resource for surgeons seeking further improvement with the procedure. © 2014 Royal Australian and New Zealand College of Ophthalmologists.

  13. Corneal biomechanical properties in floppy eyelid syndrome.

    Science.gov (United States)

    Muniesa, MaJesús; Muniesa Royo, MaJesús; March, Ana; March de Ribot, Ana; Sánchez-de-la-Torre, Manuel; Huerva, Valetín; Huerva Escanilla, Valetín; Jurjo, Carmen; Jurjo Campo, Carmen; Barbé, Ferran; Barbé Illa, Ferran

    2015-05-01

    To determine corneal biomechanical properties in patients with floppy eyelid syndrome (FES) and to compare them with eyes of controls. This case-control study included 208 eyes (72 eyes with FES and 136 without FES) of 107 patients (37 patients with FES and 70 without FES). Patients underwent a complete clinical eye examination that included corneal biomechanical evaluation carried out with the Reichert Ocular Response Analyzer. Corneal hysteresis (CH), corneal resistance factor (CRF), central corneal thickness (CCT), Goldmann-correlated intraocular pressure (IOPg), and corneal-compensated intraocular pressure (IOPcc) were evaluated. Mean CH was significantly lower in patients with FES than in those without FES (9.51 ± 1.56 vs. 11.66 ± 9.11; P corneal biomechanical properties could be changed in patients with FES, reflecting additional structural changes in FES.

  14. Corneal stroma microfibrils

    KAUST Repository

    Hanlon, Samuel D.

    2015-03-01

    Elastic tissue was first described well over a hundred years ago and has since been identified in nearly every part of the body. In this review, we examine elastic tissue in the corneal stroma with some mention of other ocular structures which have been more thoroughly described in the past. True elastic fibers consist of an elastin core surrounded by fibrillin microfibrils. However, the presence of elastin fibers is not a requirement and some elastic tissue is comprised of non-elastin-containing bundles of microfibrils. Fibers containing a higher relative amount of elastin are associated with greater elasticity and those without elastin, with structural support. Recently it has been shown that the microfibrils, not only serve mechanical roles, but are also involved in cell signaling through force transduction and the release of TGF-β. A well characterized example of elastin-free microfibril bundles (EFMBs) is found in the ciliary zonules which suspend the crystalline lens in the eye. Through contraction of the ciliary muscle they exert enough force to reshape the lens and thereby change its focal point. It is believed that the molecules comprising these fibers do not turn-over and yet retain their tensile strength for the life of the animal. The mechanical properties of the cornea (strength, elasticity, resiliency) would suggest that EFMBs are present there as well. However, many authors have reported that, although present during embryonic and early postnatal development, EFMBs are generally not present in adults. Serial-block-face imaging with a scanning electron microscope enabled 3D reconstruction of elements in murine corneas. Among these elements were found fibers that formed an extensive network throughout the cornea. In single sections these fibers appeared as electron dense patches. Transmission electron microscopy provided additional detail of these patches and showed them to be composed of fibrils (~10nm diameter). Immunogold evidence clearly

  15. Diversity of the angiogenic phenotype in non-small cell lung cancer.

    Science.gov (United States)

    McClelland, Marc R; Carskadon, Shannon L; Zhao, Liujian; White, Eric S; Beer, David G; Orringer, Mark B; Pickens, Allan; Chang, Andrew C; Arenberg, Douglas A

    2007-03-01

    Angiogenesis is crucial for tumor biology. There are many mechanisms by which tumors induce angiogenesis. We hypothesize that each individual tumor develops a unique mechanism to induce angiogenesis, and that activation of a particular angiogenic pathway suppresses the evolution of alternative pathways. We characterized 168 human non-small cell lung cancer (NSCLC) specimens for levels of angiogenic factors (angiogenic CXC chemokines, basic fibroblast growth factor, and vascular endothelial growth factor). We also induced lung tumor formation in A/J mice by injecting the tobacco carcinogen NNK. We dissected individual lung tumors and measured expression of angiogenic factors from three distinct families using real-time PCR. Finally, we controlled the angiogenic milieu using in vivo models to determine the resultant phenotype of the angiogenic factors expressed by NSCLC cells. Human tumors displayed marked variation in the expression of angiogenic factors. Individual mouse tumors, even from within the same mouse, displayed variability in their pattern of expression of angiogenic factors. In a sponge model of angiogenesis using murine lung cancer cells, implanting LLC cells with an angiogenic factor suppressed the expression of other angiogenic factors in implanted sponges. This suppressive effect was not seen in vitro. We conclude that lung cancer tumors evolve a unique and dominant angiogenic phenotype. Once an angiogenic pathway is activated, it may allow for tumor growth to proceed in the absence of a selection pressure to activate a second pathway.

  16. Biomechanics of Corneal Ring Implants

    Science.gov (United States)

    2015-01-01

    Purpose: To evaluate the biomechanics of corneal ring implants by providing a related mathematical theory and biomechanical model for the treatment of myopia and keratoconus. Methods: The spherical dome model considers the inhomogeneity of the tunica of the eye, dimensions of the cornea, lamellar structure of the corneal stroma, and asphericity of the cornea. It is used in this study for calculating a strengthening factor sf for the characterization of different ring-shaped corneal implant designs. The strengthening factor is a measure of the amount of strengthening of the cornea induced by the implant. Results: For ring segments and incomplete rings, sf = 1.0, which indicates that these implants are not able to strengthen the cornea. The intracorneal continuous complete ring (MyoRing) has a strengthening factor of up to sf = 3.2. The MyoRing is, therefore, able to strengthen the cornea significantly. Conclusions: The result of the presented biomechanical analysis of different ring-shaped corneal implant designs can explain the different postoperative clinical results of different implant types in myopia and keratoconus. PMID:26312619

  17. Corneal Protection for Burn Patients

    Science.gov (United States)

    2013-10-01

    report, Figs. 2-7. Rose Bengal (RB) photosensitization was tested because RB is FDA-allowed as a diagnostic for corneal abrasions...incisions. J Cataract Refract Surg, 30, 2420-4. Personnel supported by this grant All personnel are employed by the Massachusetts General Hospital

  18. Biomechanics of Corneal Ring Implants.

    Science.gov (United States)

    Daxer, Albert

    2015-11-01

    To evaluate the biomechanics of corneal ring implants by providing a related mathematical theory and biomechanical model for the treatment of myopia and keratoconus. The spherical dome model considers the inhomogeneity of the tunica of the eye, dimensions of the cornea, lamellar structure of the corneal stroma, and asphericity of the cornea. It is used in this study for calculating a strengthening factor sf for the characterization of different ring-shaped corneal implant designs. The strengthening factor is a measure of the amount of strengthening of the cornea induced by the implant. For ring segments and incomplete rings, sf = 1.0, which indicates that these implants are not able to strengthen the cornea. The intracorneal continuous complete ring (MyoRing) has a strengthening factor of up to sf = 3.2. The MyoRing is, therefore, able to strengthen the cornea significantly. The result of the presented biomechanical analysis of different ring-shaped corneal implant designs can explain the different postoperative clinical results of different implant types in myopia and keratoconus.

  19. Corneale crosslinking voor progressieve keratoconus

    NARCIS (Netherlands)

    Wisse, Robert P L; Soeters, Nienke; Godefrooij, Daniel A.; De Koning-Tahzib, Nayyirih G.

    2016-01-01

    Keratoconus is a corneal disease with onset typically occurring during puberty or early adulthood. The cornea progressively thins and acquires a cone-like shape which negatively affects visual acuity. In the early stages, visual acuity can be corrected with glasses or contact lenses. In more

  20. Corneal biomechanical parameters during pregnancy.

    Science.gov (United States)

    Sen, Emine; Onaran, Yüksel; Nalcacioglu-Yuksekkaya, Pinar; Elgin, Ufuk; Ozturk, Faruk

    2014-01-01

    To evaluate the variation in biomechanical properties and central corneal thickness (CCT) for each trimester during pregnancy and to compare the values with those in nonpregnant women. We prospectively studied the eyes of 32 pregnant and 34 age-matched non-pregnant women. The parameters included corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann-correlated intraocular pressure (IOP), and corneal-compensated IOP measured by the Ocular Response Analyzer (ORA). The CCT was also measured with an ultrasonic pachymeter attached to the ORA. The mean age was 27.0 ± 3.8 years in the study group and 28.0 ± 4.1 years in the control group. The mean CH measurement was 10.6 ± 1.4 mmHg in the study group and 10.1 ± 1.3 mmHg in the control group. The mean CRF value was 9.6 ± 1.7 mmHg in the study group and 10.0 ± 1.4 mmHg in the control group. The mean CCT value was 541.1 ± 22.4 µm in the study group and 536.5 ± 27.1 µm in the control group. No statistically significant differences were found regarding CH, CRF, or CCT values between the 2 groups (independent t test, p = 0.160, p = 0.355, p = 0.450, respectively). Hormonal changes during pregnancy may not affect corneal biomechanics. This may be due to the balanced effect of the various hormones on the cornea during pregnancy.

  1. Management of corneal bee sting

    Directory of Open Access Journals (Sweden)

    Razmjoo H

    2011-12-01

    Full Text Available Hassan Razmjoo1,2, Mohammad-Ali Abtahi1,2,4, Peyman Roomizadeh1,3, Zahra Mohammadi1,2, Seyed-Hossein Abtahi1,3,41Medical School, Isfahan University of Medical Sciences (IUMS; 2Ophthalmology Ward, Feiz Hospital, IUMS; 3Isfahan Medical Students Research Center (IMSRC, IUMS; 4Isfahan Ophthalmology Research Center (IORC, Feiz Hospital, IUMS, Isfahan, IranAbstract: Corneal bee sting is an uncommon environmental eye injury that can result in various ocular complications with an etiology of penetrating, immunologic, and toxic effects of the stinger and its injected venom. In this study we present our experience in the management of a middle-aged male with a right-sided deep corneal bee sting. On arrival, the patient was complaining of severe pain, blurry vision with acuity of 160/200, and tearing, which he had experienced soon after the injury. Firstly, we administered conventional drugs for eye injuries, including topical antibiotic, corticosteroid, and cycloplegic agents. After 2 days, corneal stromal infiltration and edema developed around the site of the sting, and visual acuity decreased to 100/200. These conditions led us to remove the stinger surgically. Within 25 days of follow-up, the corneal infiltration decreased gradually, and visual acuity improved to 180/200. We suggest a two-stage management approach for cases of corneal sting. For the first stage, if the stinger is readily accessible or primary dramatic reactions, including infiltration, especially on the visual axis, exist, manual or surgical removal would be indicated. Otherwise, we recommend conventional treatments for eye injuries. Given this situation, patients should be closely monitored for detection of any worsening. If the condition does not resolve or even deteriorates, for the second stage, surgical removal of the stinger under local or generalized anesthesia is indicated.Keywords: bee sting, stinger, cornea, removal, management, surgery

  2. Angiogenic factors stimulate growth of adult neural stem cells.

    Directory of Open Access Journals (Sweden)

    Andreas Androutsellis-Theotokis

    2010-02-01

    Full Text Available The ability to grow a uniform cell type from the adult central nervous system (CNS is valuable for developing cell therapies and new strategies for drug discovery. The adult mammalian brain is a source of neural stem cells (NSC found in both neurogenic and non-neurogenic zones but difficulties in culturing these hinders their use as research tools.Here we show that NSCs can be efficiently grown in adherent cell cultures when angiogenic signals are included in the medium. These signals include both anti-angiogenic factors (the soluble form of the Notch receptor ligand, Dll4 and pro-angiogenic factors (the Tie-2 receptor ligand, Angiopoietin 2. These treatments support the self renewal state of cultured NSCs and expression of the transcription factor Hes3, which also identifies the cancer stem cell population in human tumors. In an organotypic slice model, angiogenic factors maintain vascular structure and increase the density of dopamine neuron processes.We demonstrate new properties of adult NSCs and a method to generate efficient adult NSC cultures from various central nervous system areas. These findings will help establish cellular models relevant to cancer and regeneration.

  3. Angiogenic monocytes: another colorful blow to endothelial progenitors

    NARCIS (Netherlands)

    Horrevoets, Anton J. G.

    2009-01-01

    This Commentary provides perspective on a related article by Sun-Jin Kim and coworkers (Am J Pathol: 172 AJP08-0819), who assess the contribution of bone marrow-derived cells to tumor angiogenesis in a physiologic, non-myeloablative setting and conclude that the actual angiogenic cell type

  4. Cord blood angiogenic profile in normotensive pregnancies | Simmi ...

    African Journals Online (AJOL)

    ... normotensive pregnancy and dysbalance might occur during pathological pregnancy. These markers of angiogenic balance may serve as diagnostic marker and may help in explaining future risk of cardiovascular disease in these women. Keywords: Vasculogenesis; Proangiogenic and antiangiogenic factors; Pregnancy ...

  5. Heterosexual identity and heterosexism: recognizing privilege to reduce prejudice.

    Science.gov (United States)

    Simoni, J M; Walters, K L

    2001-01-01

    We propose that heterosexuals' attitudes toward their own heterosexual identity evolve in a manner similar to the development of racial identity attitudes among Whites-another dominant group with privileged social status. A more developed heterosexual identity, we hypothesized, would be associated with diminished levels of negative attitudes toward non-heterosexuals. To test our hypotheses, we administered to 154 heterosexual students Herek's (1988) Attitudes Toward Gays and Lesbians scale measuring heterosexist (i.e., anti-gay) attitudes and a version of Helms and Carter's (1990) White Racial Identity Attitude Scale (WRIAS) modified to assess heterosexual identity attitudes. Hierarchical regression analyses controlling demographic indicators partially confirmed the hypothesized associations between evolving identity stages and less heterosexist attitudes. The role of recognizing one's social privilege is proposed (though not empirically examined) as a potential mediator between developing a dominant group identity and decreasing prejudicial attitudes towards non-privileged groups. Finally, implications and recommendations for future research and addressing heterosexism are presented.

  6. Improvement in corneal scarring following bacterial keratitis.

    Science.gov (United States)

    McClintic, S M; Srinivasan, M; Mascarenhas, J; Greninger, D A; Acharya, N R; Lietman, T M; Keenan, J D

    2013-03-01

    Bacterial keratitis results in corneal scarring and subsequent visual impairment. The long-term evolution of corneal scars has not been well described. In this case series, we identified patients who had improvement in corneal scarring and visual acuity from a clinical trial for bacterial keratitis. We searched the records of the Steroids for Corneal Ulcers Trial (SCUT) for patients who had improvement in vision between the 3-month and 12-month visits and reviewed their clinical photographs. Of the 500 patients enrolled in SCUT, five patients with large central corneal scars due to bacterial keratitis are presented. All experienced improvement in rigid contact lens-corrected visual acuity from months 3 to 12. All patients also had marked improvement in corneal opacity during the same time period. None of the patients opted to have penetrating keratoplasty. Corneal scars may continue to improve even many months after a bacterial corneal ulcer has healed. The corneal remodeling can be accompanied by considerable improvement in visual acuity, such that corneal transplantation may not be necessary.

  7. Imaging, Reconstruction, And Display Of Corneal Topography

    Science.gov (United States)

    Klyce, Stephen D.; Wilson, Steven E.

    1989-12-01

    The cornea is the major refractive element in the eye; even minor surface distortions can produce a significant reduction in visual acuity. Standard clinical methods used to evaluate corneal shape include keratometry, which assumes the cornea is ellipsoidal in shape, and photokeratoscopy, which images a series of concentric light rings on the corneal surface. These methods fail to document many of the corneal distortions that can degrade visual acuity. Algorithms have been developed to reconstruct the three dimensional shape of the cornea from keratoscope images, and to present these data in the clinically useful display of color-coded contour maps of corneal surface power. This approach has been implemented on a new generation video keratoscope system (Computed Anatomy, Inc.) with rapid automatic digitization of the image rings by a rule-based approach. The system has found clinical use in the early diagnosis of corneal shape anomalies such as keratoconus and contact lens-induced corneal warpage, in the evaluation of cataract and corneal transplant procedures, and in the assessment of corneal refractive surgical procedures. Currently, ray tracing techniques are being used to correlate corneal surface topography with potential visual acuity in an effort to more fully understand the tolerances of corneal shape consistent with good vision and to help determine the site of dysfunction in the visually impaired.

  8. Corneal biomechanical properties in thyroid eye disease.

    Science.gov (United States)

    Karabulut, Gamze Ozturk; Kaynak, Pelin; Altan, Cıgdem; Ozturker, Can; Aksoy, Ebru Funda; Demirok, Ahmet; Yılmaz, Omer Faruk

    2014-06-01

    The purpose of this study is to investigate the effect of thyroid eye disease (TED) on the measurement of corneal biomechanical properties and the relationship between these parameters and disease manifestations. A total of 54 eyes of 27 individuals with TED and 52 eyes of 30 healthy control participants were enrolled. Thyroid ophthalmopathy activity was defined using the VISA (vision, inflammation, strabismus, and appearance/exposure) classification for TED. The intraocular pressure (IOP) measurement with Goldmann applanation tonometer (GAT), axial length (AL), keratometry, and central corneal thickness (CCT) measurements were taken from each patient. Corneal biomechanical properties, including corneal hysteresis (CH) and corneal resistance factor (CRF) and noncontact IOP measurements, Goldmann-correlated IOP (IOPg) and corneal-compensated IOP (IOPcc) were measured with the Ocular Response Analyzer (ORA) using the standard technique. Parameters such as best corrected visual acuity, axial length, central corneal thickness, and corneal curvature were not statistically significant between the two groups (p > 0.05). IOP measured with GAT was higher in participants with TED (p corneal resistance factor between groups. However, IOPg and IOPcc were significantly higher in TED patients. CH and VISA grading of TED patients showed a negative correlation (p = 0.007). In conclusion, TED affects the corneal biomechanical properties by decreasing CH. IOP with GAT and IOPg is found to be increased in these patients. As the severity of TED increases, CH decreases in these patients. Copyright © 2014. Published by Elsevier B.V.

  9. Clinical applications of corneal confocal microscopy

    Directory of Open Access Journals (Sweden)

    Mitra Tavakoli

    2008-06-01

    Full Text Available Mitra Tavakoli1, Parwez Hossain2, Rayaz A Malik11Division of Cardiovascular Medicine, University of Manchester and Manchester Royal Infirmary, Manchester, UK; 2University of Southampton, Southampton Eye Unit, Southampton General Hospital, Southampton, UKAbstract: Corneal confocal microscopy is a novel clinical technique for the study of corneal cellular structure. It provides images which are comparable to in-vitro histochemical techniques delineating corneal epithelium, Bowman’s layer, stroma, Descemet’s membrane and the corneal endothelium. Because, corneal confocal microscopy is a non invasive technique for in vivo imaging of the living cornea it has huge clinical potential to investigate numerous corneal diseases. Thus far it has been used in the detection and management of pathologic and infectious conditions, corneal dystrophies and ecstasies, monitoring contact lens induced corneal changes and for pre and post surgical evaluation (PRK, LASIK and LASEK, flap evaluations and Radial Keratotomy, and penetrating keratoplasty. Most recently it has been used as a surrogate for peripheral nerve damage in a variety of peripheral neuropathies and may have potential in acting as a surrogate marker for endothelial abnormalities.Keywords: corneal confocal microscopy, cornea, infective keratitis, corneal dystrophy, neuropathy

  10. Turning the tide of corneal blindness

    Directory of Open Access Journals (Sweden)

    Matthew S Oliva

    2012-01-01

    Full Text Available Corneal diseases represent the second leading cause of blindness in most developing world countries. Worldwide, major investments in public health infrastructure and primary eye care services have built a strong foundation for preventing future corneal blindness. However, there are an estimated 4.9 million bilaterally corneal blind persons worldwide who could potentially have their sight restored through corneal transplantation. Traditionally, barriers to increased corneal transplantation have been daunting, with limited tissue availability and lack of trained corneal surgeons making widespread keratoplasty services cost prohibitive and logistically unfeasible. The ascendancy of cataract surgical rates and more robust eye care infrastructure of several Asian and African countries now provide a solid base from which to dramatically expand corneal transplantation rates. India emerges as a clear global priority as it has the world′s largest corneal blind population and strong infrastructural readiness to rapidly scale its keratoplasty numbers. Technological modernization of the eye bank infrastructure must follow suit. Two key factors are the development of professional eye bank managers and the establishment of Hospital Cornea Recovery Programs. Recent adaptation of these modern eye banking models in India have led to corresponding high growth rates in the procurement of transplantable tissues, improved utilization rates, operating efficiency realization, and increased financial sustainability. The widespread adaptation of lamellar keratoplasty techniques also holds promise to improve corneal transplant success rates. The global ophthalmic community is now poised to scale up widespread access to corneal transplantation to meet the needs of the millions who are currently blind.

  11. Changes of corneal biomechanics with keratoconus.

    Science.gov (United States)

    Wolffsohn, James S; Safeen, Saima; Shah, Sunil; Laiquzzaman, Mohammad

    2012-08-01

    To perform advanced analysis of the corneal deformation response to air pressure in keratoconics compared with age- and sex-matched controls. The ocular response analyzer was used to measure the air pressure-corneal deformation relationship of 37 patients with keratoconus and 37 age (mean 36 ± 10 years)- and sex-matched controls with healthy corneas. Four repeat air pressure-corneal deformation profiles were averaged, and 42 separate parameters relating to each element of the profiles were extracted. Corneal topography and pachymetry were performed with the Orbscan II. The severity of the keratoconus was graded based on a single metric derived from anterior corneal curvatures, difference in astigmatism in each meridian, anterior best-fit sphere, and posterior best-fit sphere. Most of the biomechanical characteristics of keratoconic eyes were significantly different from normal eyes (P corneal applanation. With increasing keratoconus severity, the cornea was thinner (r = -0.407, P corneal concave deformation past applanation was quicker (dive; r2 = -0.314, P = 0.01), and the tear film index was lower (r = -0.319, P = 0.01). The variance in keratoconus severity could be accounted for by the corneal curvature and central corneal thickness (r = 0.80) with biomechanical characteristics contributing an additional 4% (total r = 0.84). The area under the receiver operating characteristic curve was 0.919 ± 0.025 for keratometry alone, 0.965 ± 0.014 with the addition of pachymetry, and 0.972 ± 0.012 combined with ocular response analyzer biomechanical parameters. Characteristics of the air pressure-corneal deformation profile are more affected by keratoconus than the traditionally extracted corneal hysteresis and corneal resistance factors. These biomechanical metrics slightly improved the detection and severity prediction of keratoconus above traditional keratometric and pachymetric assessment of corneal shape.

  12. Robotically Assisted Thoracic Surgery: Proposed Guidelines for Privileging and Credentialing.

    Science.gov (United States)

    Bhora, Faiz Y; Al-Ayoubi, Adnan M; Rehmani, Sadiq S; Forleiter, Craig M; Raad, Wissam N; Belsley, Scott G

    Increased use of robotically assisted thoracic surgery (RATS) necessitates effective credentialing guidelines to ensure safe outcomes. We provide a stepwise algorithm for granting privileges and credentials in RATS. This algorithm reflects graduated responsibility and complexity of the surgical procedures performed. Furthermore, it takes into account volume, outcomes, surgeon's competency, and appropriateness of robot usage. We performed a literature review for available strategies to grant privileges and credentials for implementing robotic surgery. The following terms were queried: robot, robotic, surgery, and credentialing. We provide this algorithm on the basis of review of the literature, our institutional experience, and the experience of other medical centers around the United States. Currently, two pathways for robotic training exist: residency and nonresidency-trained. In the United Sates, Joint Commission: Accreditation, Health Care, Certification requires hospitals to credential and privilege physicians on their medical staff. In the proposed algorithm, a credentialing designee oversees and reviews all requests. Residency-trained surgeons must fulfill 20 cases with program directors' attestation to obtain full privileges. Nonresidency-trained surgeons are required to fulfill simulation, didactics including online modules, wet laboratories (cadaver or animal), and observation of at least two cases before provisional privileges can be granted. A minimum number of cases (10 per year) are required to maintain privileges. All procedures are monitored via departmental QA/QI committee review. Investigational uses of the robot require institutional review board approval, and complex operations may require additional proctoring and QA/QI review. Safety concerns with the introduction of novel and complex technologies such as RATS must be paramount. Our algorithm takes into consideration appropriate use and serves as a basic guideline for institutions that wish to

  13. The imbalance in expression of angiogenic and anti-angiogenic factors as candidate predictive biomarker in preeclampsia

    Directory of Open Access Journals (Sweden)

    Pooneh Nikuei

    2015-07-01

    Full Text Available Preeclampsia is an important pregnancy disorder with serious maternal and fetal complications which its etiology has not been completely understood yet. Early diagnosis and management of disease could reduce its potential side effects. The vascular endothelial growth factor (VEGF family including VEGF-A is the most potent endothelial growth factor which induces angiogenesis and endothelial cell proliferation and has basic role in vasculogenesis. VEGF and its tyrosine kinase receptors (Flt1 and KDR are major factors for fetal and placental angiogenic development. Finding mechanisms involved in expression of angiogenic factors may lead to new prognostic and therapeutic points in management of preeclampsia. Recent researches, has shown capability of some anti-angiogenic factors as potential candidate to be used as early predictors for preeclampsia. Soluble fms-like tyrosin kinase-1 (sFlt1 is a truncated splice variant of the membrane-bound VEGF receptor Flt1, that is produced by the placenta and it can bind to angiogenic growth factors and neutraliz, their effects. It is also observed that the ratio of sFlt1 to placental growth factor is valuable as prognostic marker. In this review, VEGF family member’s role in angiogenesis is evaluated as biomarkers to be used for prediction of preeclampsia.

  14. Evaluation of corneal symmetry after UV corneal crosslinking for keratoconus.

    Science.gov (United States)

    Mofty, Hanan; Alzahrani, Khaled; Carley, Fiona; Harper, Sophie; Brahma, Arun; Au, Leon; Morley, Debbie; Hillarby, M Chantal

    2017-01-01

    The purpose of this study was to assess UV corneal crosslinking (CXL) treatment outcomes for keratoconus by evaluating the corneal regularity in patients through follow-up using the Oculus Pentacam. A total of 18 eyes from CXL patients with keratoconus were studied before and after CXL treatment, and six eyes from six patients who were not treated with CXL served as controls. Treated patients had Pentacam images taken before CXL treatment and regularly 3 months post treatment up to the 12th month. Controls were imaged during their first appointment and after 12 months. Symmetry and asphericity were evaluated and correlated with both best-corrected visual acuity (BCVA) and maximum K -readings. In the CXL-treated group, there was a significant improvement in the index of symmetrical variation (ISV) and keratoconus index (KI) at 3 months and in the index of height asymmetry (IHA) and minimum radius of curvature ( R min ) at 9 months post treatment. On the contrary, the untreated group's indices showed some significant worsening in ISV, KI, central keratoconus index (CKI), and R min . A novel finding in our study was a slight positive shift of anterior asphericity in the 6 mm, 7 mm, and 8 mm 3 months after treatment, which had a correlation with BCVA ( R 2 =0.390, p =0.053) and a strong correlation with maximum K -reading ( R 2 =0.690, p =0.005). However, the untreated group had no significant changes after 1 year. The corneal asymmetrical shape is associated with the spherical aberration alteration influenced by temporal evolution of surface ablation and increased corneal haze. However, insignificant changes in symmetry attest the stabilization effect on cornea postoperatively as compared with controls.

  15. Posterior corneal shape : Comparison of height data from 3 corneal topographers

    NARCIS (Netherlands)

    de Jong, Tim; Sheehan, Matthew T.; Koopmans, Steven A.; Jansonius, Nomdo M.

    Purpose: To compare the ability of 3 clinical corneal topographers to describe the posterior corneal shape. Setting: University Medical Center Groningen, the Netherlands. Design: Prospective observational study. Methods: Corneas of healthy participants were measured twice with a dual Scheimpflug

  16. Chitosan and thiolated chitosan: Novel therapeutic approach for preventing corneal haze after chemical injuries.

    Science.gov (United States)

    Zahir-Jouzdani, Forouhe; Mahbod, Mirgholamreza; Soleimani, Masoud; Vakhshiteh, Faezeh; Arefian, Ehsan; Shahosseini, Saeed; Dinarvand, Rasoul; Atyabi, Fatemeh

    2018-01-01

    Corneal haze, commonly caused by deep physical and chemical injuries, can greatly impair vision. Growth factors facilitate fibroblast proliferation and differentiation, which leads to haze intensity. In this study, the potential effect of chitosan (CS) and thiolated-chitosan (TCS) nanoparticles and solutions on inhibition of fibroblast proliferation, fibroblast to myofibroblast differentiation, neovascularization, extracellular matrix (ECM) deposition, and pro-fibrotic cytokine expression was examined. Transforming growth factor beta-1 (TGFβ1) was induced by interleukin-6 (IL6) in human corneal fibroblasts and expression levels of TGFβ1, Platelet-derived growth factor (PDGF), α-smooth muscle actins (α-SMA), collagen type I (Col I), fibronectin (Fn) and vascular endothelial growth factor (VEGF) were quantified using qRT-PCR. To assess wound-healing capacity, TCS-treated mice were examined for α-SMA positive cells, collagen deposition, inflammatory cells and neovascularization through pathological immunohistochemistry. The results revealed that CS and TCS could down-regulate the expression levels of TGFβ1 and PDGF comparable to that of TGFβ1 knockdown experiment. However, down-regulation of TGFβ1 was not regulated through miR29b induction. Neovascularization along with α-SMA and ECM deposition were significantly diminished. According to these findings, CS and TCS can be considered as potential anti-fibrotic and anti-angiogenic therapeutics. Furthermore, TCS, thiolated derivative of CS, will increase mucoadhesion of the polymer at the corneal surface which makes the polymer efficient and non-toxic therapeutic approach for corneal injuries. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Value of recombinant human epidermal growth factor in corneal wound repair after corneal foreign body elimination

    OpenAIRE

    Hong-Jie Han

    2013-01-01

    AIM: To investigate the repair efficacy of recombinant human epidermal growth factor on corneal epithelium after corneal foreign body eliminating operation. METHODS: There were 102 patients with corneal foreign body(188 affected eyes)chosen for the study. All patients were divided into treatment group and control group according to the random number table. Both groups received corneal foreign body elimination by slit lamp. Postoperatively, the treatment group was given eye drops containing ep...

  18. Variation of corneal refractive index with hydration

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young L; Walsh, Joseph T Jr.; Goldstick, Thomas K; Glucksberg, Matthew R [Biomedical Engineering Department, Northwestern University, Evanston, IL 60208 (United States)

    2004-03-07

    We report the effect of changes in the corneal hydration on the refractive index of the cornea. Using optical coherence tomography (OCT), the geometrical thickness and the group refractive index of the bovine cornea were derived simultaneously as the corneal hydration was varied. The corneal hydration was then calculated from the corneal thickness. The group refractive index of the cornea increased non-linearly as the cornea dehydrated. In addition, a simple mathematical model was developed, based on the assumption that changes in corneal hydration occur only in the interfibrilar space with constant water content within the collagen fibrils. Good agreement between the experimental results and the mathematical model supports the assumption. The results also demonstrate that the measurement of refractive index is a quantitative indicator of corneal hydration.

  19. Corneal Toxicity Following Exposure to Asclepias Tuberosa

    DEFF Research Database (Denmark)

    Mikkelsen, Lauge Hjorth; Hamoudi, Hassan; Gül, Cigdem Altuntas

    2017-01-01

    PURPOSE: To present a case of corneal toxicity following exposure to milky plant latex from Asclepias tuberosa. METHODS: A 70-year-old female presented with blurred vision and pain in her left eye after handling an Ascepias tuberosa. Clinical examination revealed a corneal stromal oedema with small...... that inhibit the Na+/ K+-ATPase in the corneal endothelium. The oedema resolved after 96 hours. After nine months the best corrected visual acuity was 20/20. CONCLUSION: Corneal toxicity has previously been reported for plants of the Asclepias family. This is a rare case describing severe corneal toxicity...... caused by exposure to latex from Asclepias tuberosa. Handling of plants of the Asclepias family should be kept as a differential diagnosis in cases of acute corneal toxicity....

  20. Genetics Home Reference: lattice corneal dystrophy type I

    Science.gov (United States)

    ... corneal dystrophy type I lattice corneal dystrophy type I Printable PDF Open All Close All Enable Javascript ... expand/collapse boxes. Description Lattice corneal dystrophy type I is an eye disorder that affects the clear, ...

  1. Immunoglobulins in granular corneal dystrophy Groenouw type I

    DEFF Research Database (Denmark)

    Møller, H U; Bojsen-Møller, M; Schrøder, H D

    1993-01-01

    Three patients with granular corneal dystrophy Groenouw type I underwent corneal grafting, and cryostat sections of the corneal buttons were examined immunohistochemically for immunoglobulins. Positive results were obtained for IgG, Kappa-, and Lambda chains with immunofluorescence technique. The...

  2. Corneal epithelium in penetrating keratoplasty.

    Science.gov (United States)

    Meyer, R F; Bobb, K C

    1980-08-01

    We studied corneal epithelium in 66 patients with bullous keratopathy treated with penetrating keratoplasty using McCarey-Kaufman stored donor corneas. Epithelium was evaluated at times of storage, surgery, and postoperative dressing changes. Epithelium was intact in 43 of the donor corneas at storage, and 23 had 5 to 100% (median, 50%) epithelium missing. At the end of the keratoplasty procedure, 16 grafts had epithelium intact, and 50 had 5 to 100% (median, 20%) epithelium missing. Postoperative epithelial healing time ranged from one to 12 days, with a median of two days. Postoperative healing was significantly prolonged when donor corneal epithelium was missing at keratoplasty. As the amount of epithelium intact at the end of surgery decreased, the number of days to heal postoperatively increased. We found that donor corneas could be stored as long as 79 hours, with 63 hours in McCarey-Kaufman medium, and still have epithelium intact at the end of the keratoplasty procedure.

  3. Corneal astigmatism following cataract extraction.

    Science.gov (United States)

    Wishart, M S; Wishart, P K; Gregor, Z J

    1986-01-01

    The changes in corneal curvature in the first six months after cataract extraction were studied by performing sequential keratometry on a group of 57 patients. 8/0 Virgin silk interrupted sutures were used for the closure of corneoscleral incisions, and 10/0 monofilament tied in double running (bootlace) or single running (continuous) fashion was used for corneal wound closure. A high degree of with-the-rule astigmatism was evident in all patients two weeks postoperatively, but thereafter the character of the astigmatism produced by 8/0 virgin silk and 10/0 monofilament closure was quite different: in the 8/0 virgin silk group there was an early and pronounced shift in the axis of astigmatism to against-the-rule, whereas in the 10/0 monofilament group there was little further change in the astigmatism unless the sutures were removed. Wound compression and wound gape as factors responsible for these changes are discussed. PMID:3539177

  4. Glaucoma and Corneal Transplant Procedures

    Directory of Open Access Journals (Sweden)

    Ammar M. Al-Mahmood

    2012-01-01

    Full Text Available Glaucoma after corneal transplantation is a leading cause of ocular morbidity after penetrating keratoplasty. The incidence reported is highly variable and a number of etiologic factors have been identified. A number of treatment options are available; surgical intervention for IOP control is associated with a high incidence of graft failure. IOP elevation is less frequently seen following deep anterior lamellar keratoplasty. Descemet's striping-automated endothelial keratoplasty is also associated with postprocedure intraocular pressure elevation and secondary glaucoma and presents unique surgical challenges in patients with preexisting glaucoma surgeries. Glaucoma exists in up to three-quarters of patients who undergo keratoprosthesis surgery and the management if often challenging. The aim of this paper is to highlight the incidence, etiology, and management of glaucoma following different corneal transplant procedures. It also focuses on the challenges in the diagnosis of glaucoma and intraocular pressure monitoring in this group of patients.

  5. Corneal hemangiosarcoma in a cat.

    Science.gov (United States)

    Cazalot, G; Regnier, A; Deviers, A; Serra, F; Lucas, M N; Etienne, C L; Letron, I Raymond

    2011-09-01

    A 10 year-old castrated male Domestic Short-hair cat with a history of chronic bilateral keratitis was referred for assessment of a red, elevated mass involving the left cornea. The rapid growth of the mass, over a month period in combination with pronounced vascularization and invasion of the corneal surface suggested an aggressive inflammatory or neoplastic process. Following keratectomy, the lesion was diagnosed histopathologically as a hemangiosarcoma. The tumor recurred locally within 3 weeks and enucleation was performed. Histopathologic examination of the globe confirmed the diagnosis and did not reveal infiltration of the limbus and conjunctiva. No signs of local recurrence or metastatic disease have been observed 18 months following enucleation. To the authors' knowledge this is the first case of primary corneal hemangiosarcoma described in the feline species. © 2011 American College of Veterinary Ophthalmologists.

  6. Evaluation of corneal symmetry after UV corneal crosslinking for keratoconus

    Directory of Open Access Journals (Sweden)

    Mofty H

    2017-11-01

    Full Text Available Hanan Mofty,1,2 Khaled Alzahrani,2 Fiona Carley,3 Sophie Harper,3 Arun Brahma,3 Leon Au,3 Debbie Morley,3 M Chantal Hillarby2 1Optometry Department, College of Applied Medical Science, King Saud University, Riyadh, Kingdom of Saudi Arabia; 2Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, 3Manchester Royal Eye Hospital, Manchester, UK Purpose: The purpose of this study was to assess UV corneal crosslinking (CXL treatment outcomes for keratoconus by evaluating the corneal regularity in patients through follow-up using the Oculus Pentacam.Patients and methods: A total of 18 eyes from CXL patients with keratoconus were studied before and after CXL treatment, and six eyes from six patients who were not treated with CXL served as controls. Treated patients had Pentacam images taken before CXL treatment and regularly 3 months post treatment up to the 12th month. Controls were imaged during their first appointment and after 12 months. Symmetry and asphericity were evaluated and correlated with both best-corrected visual acuity (BCVA and maximum K-readings.Results: In the CXL-treated group, there was a significant improvement in the index of symmetrical variation (ISV and keratoconus index (KI at 3 months and in the index of height asymmetry (IHA and minimum radius of curvature (Rmin at 9 months post treatment. On the contrary, the untreated group’s indices showed some significant worsening in ISV, KI, central keratoconus index (CKI, and Rmin. A novel finding in our study was a slight positive shift of anterior asphericity in the 6 mm, 7 mm, and 8 mm 3 months after treatment, which had a correlation with BCVA (R2=0.390, p=0.053 and a strong correlation with maximum K-reading (R2=0.690, p=0.005. However, the untreated group had no significant changes after 1 year.Conclusion: The corneal asymmetrical shape is associated with the spherical aberration alteration

  7. Corneal Donor Tissue Preparation for Endothelial Keratoplasty

    OpenAIRE

    Woodward, Maria A.; Titus, Michael; Mavin, Kyle; Shtein, Roni M.

    2012-01-01

    Over the past ten years, corneal transplantation surgical techniques have undergone revolutionary changes1,2. Since its inception, traditional full thickness corneal transplantation has been the treatment to restore sight in those limited by corneal disease. Some disadvantages to this approach include a high degree of post-operative astigmatism, lack of predictable refractive outcome, and disturbance to the ocular surface. The development of Descemet's stripping endothelial keratoplasty (DSEK...

  8. Corneal Biomechanics Determination in Healthy Myopic Subjects

    OpenAIRE

    Kunliang Qiu; Xuehui Lu; Riping Zhang; Geng Wang; Mingzhi Zhang

    2016-01-01

    Purpose. To determine the corneal biomechanical properties by using the Ocular Response Analyzer? and to investigate potential factors associated with the corneal biomechanics in healthy myopic subjects. Methods. 135 eyes from 135 healthy myopic subjects were included in this cross-sectional observational study. Cornea hysteresis (CH), corneal resistance factor (CRF), cornea-compensated intraocular pressure (IOPcc), and Goldmann-correlated intraocular pressure (IOPg) were determined with the ...

  9. Advancing Social Justice Work at the Intersections of Multiple Privileged Identities

    Science.gov (United States)

    Kendall, Frances E.; Wijeyesinghe, Charmaine L.

    2017-01-01

    The authors discuss how the concept of social location and tenets of intersectionality inform the understanding of power and privilege, our work with people with multiple privileged identities, and the preparation of social justice educators.

  10. Refractive surgery following corneal graft.

    Science.gov (United States)

    Alió, Jorge L; Abdou, Ahmed A; Abdelghany, Ahmed A; Zein, Ghassam

    2015-07-01

    To review the different surgical procedures for management of postkeratoplasty refractive errors after total suture removal. There are different surgical options to address residual refractive errors that frequently occur after corneal transplantation. The correction can be done on the corneal surface or intraocular with intraocular lens (IOL) implantation which requires complete tectonic and refractive stability after suture removal. The most commonly used procedures are photorefractive keratectomy, laser in-situ keratomileusis and Phakic IOLs. Keratoplasty has been profited by recent advances in refractive surgery. Custom excimer laser ablation is an alternative way to treat irregular errors. New IOL modalities are good practical options for a wide range of errors. Femtosecond laser, as a new option in the toolbox, can modify corneal grafting refractive results and assist corrective refractive procedures. Although being the most successful organ transplantation, keratoplasty is usually followed by significant ametropia. Different corrective modalities exist and the choice should fit ocular conditions, patient requirements, surgeon skills and the available technologies. Recent advances in ophthalmic surgery have improved the outcomes.

  11. Refractive surgery after corneal transplantation.

    Science.gov (United States)

    Chang, Daniel H; Hardten, David R

    2005-08-01

    Many patients who have undergone corneal transplantation are unable to achieve satisfactory visual acuity with spectacle and contact lens correction alone. For these patients, refractive surgery becomes a viable option to reduce the post-keratoplasty ametropia. With the many recent advances in refractive surgery for naturally occurring refractive error, new possibilities arise for application to this complicated set of patients. This review discusses key recent developments in refractive surgery after corneal transplantation. The biomechanical effects of incisional keratotomy on post-keratoplasty corneas continue to be studied, and these techniques remain a common and simple method of reducing astigmatism. Photorefractive keratectomy, previously problematic for regression and haze formation, is gaining new prominence as early experience with the adjunctive use of mitomycin C has demonstrated good results. Long-term studies with laser in-situ keratomileusis (LASIK) have continued to show good safety and efficacy. Modern developments in cataract surgery appear to have lower incidences of graft rejection and failure. Developments in lens implantation technology continue to offer expanding options for intraocular refractive surgery. Although visual rehabilitation after corneal transplantation remains a formidable challenge, developments in refractive surgery for naturally occurring ametropias directly translate into an improved ability to help these most challenging refractive cases. Continued research will bring about improved efficacy while maintaining a high level of safety.

  12. Experimental assessment of corneal anisotropy.

    Science.gov (United States)

    Elsheikh, Ahmed; Brown, Michael; Alhasso, Daad; Rama, Paolo; Campanelli, Marino; Garway-Heath, David

    2008-02-01

    To determine the variation of corneal biomechanical properties with anatomical orientation. Strip specimens extracted from fresh porcine corneas were tested under uniaxial tension with strain rates representing static and dynamic loading conditions. The specimens were extracted from the vertical, horizontal, and 45 degrees diagonal directions. The load elongation results were used to derive the stress-strain behavior of each specimen. The average behavior for specimens taken in each anatomical direction was determined along with the effect of strain rate. Specimens from a small number of human corneas were included in the study to verify the findings. Specimens extracted from the vertical direction of porcine and human corneas demonstrated the highest strength (fracture stress) followed by horizontal then diagonal specimens. Vertical specimens were 10% to 20% stronger than horizontal specimens in porcine and human corneas. At low strain rates (1%/min), vertical specimens displayed similar stiffness (resistance to deformation) to horizontal specimens but greater stiffness than diagonal specimens. On increasing the strain rate to 500%/min, the stiffness behavior matched that of strength with vertical specimens being 10% to 20% stiffer than horizontal specimens in porcine and human corneas. The corneal anisotropic behavior is compatible with the preferential orientation of stromal fibrils in the vertical and horizontal directions. Quantifying the effect of this nonuniform fibril organization on corneal anisotropic behavior will be useful in developing numerical models of the cornea for applications where its integrity is compromised such as in simulating refractive surgery procedures.

  13. Obtaining corneal tissue for keratoplasty.

    Science.gov (United States)

    Navarro Martínez-Cantullera, A; Calatayud Pinuaga, M

    2016-10-01

    Cornea transplant is the most common tissue transplant in the world. In Spain, tissue donation activities depend upon transplant coordinator activities and the well-known Spanish model for organ and tissue donation. Tissue donor detection system and tissue donor evaluation is performed mainly by transplant coordinators using the Spanish model on donation. The evaluation of a potential tissue donor from detection until recovery is based on an exhaustive review of the medical and social history, physical examination, family interview to determine will of the deceased, and a laboratory screening test. Corneal acceptance criteria for transplantation have a wider spectrum than other tissues, as donors with active malignancies and infections are accepted for kearatoplasty in most tissue banks. Corneal evaluation during the whole process is performed to ensure the safety of the donor and the recipient, as well as an effective transplant. Last step before processing, corneal recovery, must be performed under standard operating procedures and in a correct environment. Copyright © 2016 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.

  14. Central corneal thickness in glaucoma.

    Science.gov (United States)

    Sng, Chelvin C A; Ang, Marcus; Barton, Keith

    2017-03-01

    The purpose of this review is to summarize the role of central corneal thickness (CCT) in the clinical management of a glaucoma patient. The prognostic value of CCT is well recognized in patients with ocular hypertension. However, its predictive value in other glaucoma suspects and patients with established glaucoma is less certain. Tonometry artefacts can result from variations in CCT. However, an adequately validated correction algorithm for Goldmann applanation tonometry measurements does not exist. Newer methods of tonometry are potentially less influenced by CCT but are limited in their clinical use. There may also be biological and genetic associations between corneal thickness and glaucoma. Demographics, environmental factors, glaucoma treatment and the measurement device used have a significant influence on CCT, and should be considered when interpreting the effect of cornea thickness in patients with glaucoma. New measurements of the biomechanical properties of the cornea are likely to be better approximations of the globe biomechanics than CCT, but these require further evaluation. The clinical significance of CCT is well recognized in the context of glaucoma diagnosis and management, though the extent of its importance remains debatable. Corneal biomechanical properties may be more significantly associated with glaucoma than CCT.

  15. White Privilege, Psychoanalytic Ethics, and the Limitations of ...

    African Journals Online (AJOL)

    The moral and philosophical interrogation of white privilege remains an imperative in post-apartheid South Africa. Whereas the critique of whiteness involves both philosophical and psychological scrutiny, subsequent calls for white political silence and withdrawal have yet to be subjected to adequate psychological analysis ...

  16. 24 CFR 100.146 - Limited use of privileged information.

    Science.gov (United States)

    2010-04-01

    ... FAIR HOUSING DISCRIMINATORY CONDUCT UNDER THE FAIR HOUSING ACT Discrimination in Residential Real... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Limited use of privileged information. 100.146 Section 100.146 Housing and Urban Development Regulations Relating to Housing and Urban...

  17. 24 CFR 100.144 - Scope of privilege.

    Science.gov (United States)

    2010-04-01

    ... DISCRIMINATORY CONDUCT UNDER THE FAIR HOUSING ACT Discrimination in Residential Real Estate-Related Transactions... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Scope of privilege. 100.144 Section 100.144 Housing and Urban Development Regulations Relating to Housing and Urban Development OFFICE OF...

  18. 24 CFR 100.145 - Loss of privilege.

    Science.gov (United States)

    2010-04-01

    ... DISCRIMINATORY CONDUCT UNDER THE FAIR HOUSING ACT Discrimination in Residential Real Estate-Related Transactions... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Loss of privilege. 100.145 Section 100.145 Housing and Urban Development Regulations Relating to Housing and Urban Development OFFICE OF...

  19. A Faceless Bureaucrat Ponders Special Education, Disability, and White Privilege.

    Science.gov (United States)

    Smith, Anne

    2001-01-01

    The first part of this article critiques categorical approaches to special education, overrepresentation of minority children in special education, inclusion and exclusion, and white privilege. The second part of the article describes the potential of multicultural education, transformation, and participatory leadership approaches to address the…

  20. Privilege, shame and new choices towards reconciliation. An autobiographical approach

    Directory of Open Access Journals (Sweden)

    J C M�ller

    2005-10-01

    Full Text Available A narrative and autobiographical approach is taken in this article in order to explore and explain reconciliation. In the process the concepts of privilege, shame and new choices, within a specific story, are taken as the guiding beacons on the road to reconciliation in the South African situation.�

  1. The Color of Supremacy: Beyond the Discourse of "White Privilege"

    Science.gov (United States)

    Leonardo, Zeus

    2004-01-01

    In the last decade, the study of white privilege has reached currency in the educational and social science literature. Concerned with the circuits and meanings of whiteness in everyday life, scholars have exposed the codes of white culture, worldview of the white imaginary, and assumptions of the invisible marker that depends on the racial other…

  2. Privileged Communication in Selected Helping Professions: A Comparison among Statutes.

    Science.gov (United States)

    Herlihy, Barbara; Sheeley, Vernon Lee

    1987-01-01

    Presents findings of an examination and assessment of existing privileged communication statutes and rules of evidence in the 50 states and the District of Columbia for clients of selected helping professionals: psychologists, social workers, marriage and family therapists or counselors, school counselors, and licensed professional counselors.…

  3. Logistic Costs of Privileged Procedures in the Republic of Croatia

    Directory of Open Access Journals (Sweden)

    Čedomir Ivaković

    2006-07-01

    Full Text Available Logistic processes condition more and more the rationalizationof time required for manipulation of goods (loading,unloading, storage. The customs representation costs that arethe result of loss of time due to the customs procedures exclusivelyduring the working hours of the customs office affect alsothe total logistic costs, and may be significantly reduced by applyingthe privileged procedures in import and export.

  4. 32 CFR 634.15 - Restricted driving privileges or probation.

    Science.gov (United States)

    2010-07-01

    ... must be reinstated. The burden of proof for reinstatement of driving privileges lies with the person... personal or family hardships. (3) Delays exceeding 90 days, not attributed to the person concerned, in the... facilities such as hospital, commissary, and or other facilities) will be specified in writing and provided...

  5. Awakening to White Privilege and Power in Canada

    Science.gov (United States)

    Syed, Khalida Tanvir; Hill, Anne

    2011-01-01

    In this article two narratives are used to illustrate how self-awareness of "White" as skin colour reveals associated subtle aspects of power and privilege and with that, an ethic of personal and professional responsibility. The narratives connect experience and action with the conceptual framework of a third, liminal space,…

  6. White Privilege, Psychoanalytic Ethics, and the Limitations of ...

    African Journals Online (AJOL)

    ... 'rights of silence' – provide a third area of questioning. The paper ends by introducing the Lacanian ideas of subjective destitution and identification with the symptom. These concepts throw a critical light on disavowals of white privilege and provide a novel means of thinking how white narcissism might be relinquished.

  7. Personal aggrandizement: an insight into Ben Enwonwu's privilege ...

    African Journals Online (AJOL)

    This paper titled Personal Aggrandizement: An Insight into Ben Enwonwu's Privilege Position in the Evolution of Nigerian Art, looks at the first trained artists. How the artists were classified by their styles either in the naturalistic, the abstract or the expressive imageries. The study examines and compares the contributions of ...

  8. Hidden climato-economic roots of differentially privileged cultures

    NARCIS (Netherlands)

    Van de Vliert, Evert

    This theory-based study tests the interactive impacts of the demands of thermal climate and wealth resources on variations in privileged culture represented by mental health, personal freedom, and political democracy. Multiple regression analysis of aggregated survey data covering 106 countries

  9. Social Privilege, Social Justice, and Group Counseling: An Inquiry

    Science.gov (United States)

    Smith, Lance C.; Shin, Richard Q.

    2008-01-01

    The construct of social privilege is ubiquitous within the multicultural and social justice literature. However, the group work literature has yet to integrate the construct into group theory, processes, and training. In this article, we review the group literature on multicultural and diversity issues. Also, we examine the multicultural and…

  10. Understanding Unearned Privilege: An Experiential Activity for Counseling Students

    Science.gov (United States)

    Cook, Katrina; Lusk, Aisha; Miller, Laura Christina; Dodier, Oscar Esteban; Salazar, Ana M.

    2012-01-01

    The Association for Multicultural Counseling and Development stresses the importance of counselors to develop multicultural competencies that include attitudes, knowledge, and skills. Counselor educators face the challenge of helping their students develop multicultural counseling competence including an awareness of unearned privilege. This…

  11. 76 FR 6554 - Appeal Authority When Researcher Privileges Are Revoked

    Science.gov (United States)

    2011-02-07

    ... privileges have been revoked for specific behaviors, from the Archivist of the United States to the Deputy Archivist of the United States. This change will align the appeal authority for researchers whose research..., contractor, other building occupants, or property, which is the Deputy Archivist of the United States...

  12. Relationship between Corneal Sensation, Blinking, and Tear Film Quality

    National Research Council Canada - National Science Library

    Nosch, Daniela Sonja; Pult, Heiko; Albon, Julie; Purslow, Christine; Murphy, Paul John

    2016-01-01

    PURPOSETo examine the possible role of corneal sensitivity and tear film quality in triggering a blink by investigating the relationship between blink rate, central corneal sensitivity threshold (CST...

  13. 17 CFR 240.12f-3 - Termination or suspension of unlisted trading privileges.

    Science.gov (United States)

    2010-04-01

    ... unlisted trading privileges. 240.12f-3 Section 240.12f-3 Commodity and Securities Exchanges SECURITIES AND... Regulations Under the Securities Exchange Act of 1934 Unlisted Trading § 240.12f-3 Termination or suspension of unlisted trading privileges. (a) The issuer of any security for which unlisted trading privileges...

  14. Privileged Communications by Psychologists, Social Workers, and Drug and Alcohol Specialists.

    Science.gov (United States)

    Robbins, Jerry H.

    Under the laws of the United States, privileged communications are strictly limited to a few well-defined categories, such as communications between attorney and client, clergyman and penitent, and physician and patient. Certain official documents are recognized as privileged, and a privilege is accorded law enforcement officers to decline to…

  15. Discriminatory Policy among the Undergraduate Students towards Racism and White Privilege in America

    Science.gov (United States)

    Sankar, G.

    2014-01-01

    This paper addresses racism and white privilege in America. Racism is generally discriminatory policy and behavior aimed at oppressing non whites whereas white privilege is the advantage gained by whites that is not due to ability or merit. It is argued that white privilege is largely invisible and that this allows the current unacceptable status…

  16. Difficult Dialogues, Privilege and Social Justice: Uses of the Privileged Identity Exploration (PIE) Model in Student Affairs Practice

    Science.gov (United States)

    Watt, Sherry K.

    2007-01-01

    This article will introduce the Privileged Identity Exploration (PIE) Model. This model identifies eight (8) defense modes associated with behaviors individuals display when engaged in difficult dialogues about social justice issues. Implications for the model and ways it can be used to assist facilitators as they engage participants in…

  17. Response of corneal hysteresis and central corneal thickness following clear corneal cataract surgery.

    Science.gov (United States)

    Kandarakis, Artemios; Soumplis, Vasileios; Karampelas, Michalis; Koutroumanos, Ioannis; Panos, Christos; Kandarakis, Stylianos; Karagiannis, Dimitrios

    2012-09-01

    To evaluate the effect of routine phacoemulsification in corneal viscoelastic properties determined by corneal hysteresis (CH) and central corneal thickness (CCT) and to explore the impact of phaco energy on the above parameters. Forty-one eyes of 41 patients undergoing cataract surgery were enrolled in this prospective study. CH and CCT were measured preoperatively, 1 day and 1 week postoperatively. CCT measurement was performed using a non-contact optical pachymeter followed by ocular response analyzer (ORA) examination. Intraoperatively ultrasound time, average phaco power and effective phaco time (EPT) were recorded. Mean CH was 10.05±1.86 mmHg preoperatively, 8.25±1.85 mmHg 1 day and 9.12±1.37 mmHg 1 week postoperatively (pcorneal alterations following cataract surgery resulted in a statistical change in CH and CCT. These two parameters responded in a different manner that clearly demarcates their different nature. On the first postoperative day, CCT increase was correlated at a statistically significant level with intraoperative EPT. This correlation was not found with CH reduction. Other factors, besides cornea oedema or phacoemulsification energy, could be responsible for this CH modification. © 2011 The Authors. Acta Ophthalmologica © 2011 Acta Ophthalmologica Scandinavica Foundation.

  18. Prevention of the Angiogenic Switch in Human Breast Cancer

    Science.gov (United States)

    2009-03-01

    conventional dosing of chemotherapy. New pharmacology : oral drugs that increase endogenous angiogenesis inhibitors. The clinical finding that...angiogenic proteins, opening the way for a new field of pharmacology (FIG.7). Endostatin is increased by tamoxifen136, celecoxib137 and (in joint...thrombospondin-1 (clone A6.1, Lab Vision, Fremont, CA) staining, sections were pretreated with pepsin for 15 minutes at 37uC (Biomeda, Foster City, CA

  19. Platelet lysate-based pro-angiogenic nanocoatings.

    Science.gov (United States)

    Oliveira, Sara M; Pirraco, Rogério P; Marques, Alexandra P; Santo, Vítor E; Gomes, Manuela E; Reis, Rui L; Mano, João F

    2016-03-01

    Human platelet lysate (PL) is a cost-effective and human source of autologous multiple and potent pro-angiogenic factors, such as vascular endothelial growth factor A (VEGF A), fibroblast growth factor b (FGF b) and angiopoietin-1. Nanocoatings previously characterized were prepared by layer-by-layer assembling incorporating PL with marine-origin polysaccharides and were shown to activate human umbilical vein endothelial cells (HUVECs). Within 20 h of incubation, the more sulfated coatings induced the HUVECS to the form tube-like structures accompanied by an increased expression of angiogenic-associated genes, such as angiopoietin-1 and VEGF A. This may be a cost-effective approach to modify 2D/3D constructs to instruct angiogenic cells towards the formation of neo-vascularization, driven by multiple and synergistic stimulations from the PL combined with sulfated polysaccharides. The presence, or fast induction, of a stable and mature vasculature inside 3D constructs is crucial for new tissue formation and its viability. This has been one of the major tissue engineering challenges, limiting the dimensions of efficient tissue constructs. Many approaches based on cells, growth factors, 3D bioprinting and channel incorporation have been proposed. Herein, we explored a versatile technique, layer-by-layer assembling in combination with platelet lysate (PL), that is a cost-effective source of many potent pro-angiogenic proteins and growth factors. Results suggest that the combination of PL with sulfated polyelectrolytes might be used to introduce interfaces onto 2D/3D constructs with potential to induce the formation of cell-based tubular structures. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  20. The angiogenic potential of leukocyte- and platelet-rich fibrin

    OpenAIRE

    Berkmans, Kirsten

    2016-01-01

    Introduction: L-PRF promotes tissue healing in clinical applications such as dental surgery. However, little is known about the mechanisms of action. Angiogenesis is a key process in tissue regeneration. Growth factors, fibrin and leukocytes, as present in L-PRF, are known to be important in angiogenesis. The goal of this study was to investigate whether L-PRF induces blood vessel formation. Materials and methods: The angiogenic cytokine profile of L-PRF CM and exudate was determined by an...

  1. CXC and CC Chemokines as Angiogenic Modulators in Nonhaematological Tumors

    Directory of Open Access Journals (Sweden)

    Matteo Santoni

    2014-01-01

    Full Text Available Chemokines are a superfamily of structurally homologous heparin-binding proteins that includes potent inducers and inhibitors of angiogenesis. The imbalance between angiogenic and angiostatic chemokine activities can lead to abnormalities, such as chronic inflammation, dysplastic transformation, and even tumor development and spreading. In this review, we summarize the current literature regarding the role of chemokines as modulators of tumor angiogenesis and their potential role as therapeutic targets in patients with nonhaematological tumors.

  2. Corneal donor tissue preparation for endothelial keratoplasty.

    Science.gov (United States)

    Woodward, Maria A; Titus, Michael; Mavin, Kyle; Shtein, Roni M

    2012-06-12

    Over the past ten years, corneal transplantation surgical techniques have undergone revolutionary changes. Since its inception, traditional full thickness corneal transplantation has been the treatment to restore sight in those limited by corneal disease. Some disadvantages to this approach include a high degree of post-operative astigmatism, lack of predictable refractive outcome, and disturbance to the ocular surface. The development of Descemet's stripping endothelial keratoplasty (DSEK), transplanting only the posterior corneal stroma, Descemet's membrane, and endothelium, has dramatically changed treatment of corneal endothelial disease. DSEK is performed through a smaller incision; this technique avoids 'open sky' surgery with its risk of hemorrhage or expulsion, decreases the incidence of postoperative wound dehiscence, reduces unpredictable refractive outcomes, and may decrease the rate of transplant rejection. Initially, cornea donor posterior lamellar dissection for DSEK was performed manually resulting in variable graft thickness and damage to the delicate corneal endothelial tissue during tissue processing. Automated lamellar dissection (Descemet's stripping automated endothelial keratoplasty, DSAEK) was developed to address these issues. Automated dissection utilizes the same technology as LASIK corneal flap creation with a mechanical microkeratome blade that helps to create uniform and thin tissue grafts for DSAEK surgery with minimal corneal endothelial cell loss in tissue processing. Eye banks have been providing full thickness corneas for surgical transplantation for many years. In 2006, eye banks began to develop methodologies for supplying precut corneal tissue for endothelial keratoplasty. With the input of corneal surgeons, eye banks have developed thorough protocols to safely and effectively prepare posterior lamellar tissue for DSAEK surgery. This can be performed preoperatively at the eye bank. Research shows no significant difference in

  3. Biomarkers in Tumor Angiogenesis and Anti-Angiogenic Therapy

    Directory of Open Access Journals (Sweden)

    Michael Medinger

    2011-10-01

    Full Text Available Tumor angiogenesis has been identified to play a critical role in tumor growth and tumor progression, and is regulated by a balance of angiogenic and anti-angiogenic cytokines. Among them VEGF (vascular endothelial growth factor and its signaling through its receptors are of crucial relevance. Inhibition of VEGF signaling by monoclonal antibodies or small molecules (kinase inhibitors has already been successfully established for the treatment of different cancer entities and multiple new drugs are being tested in clinical trials. However not all patients are likely to respond to these therapies, but to date there are no reliable biomarkers available to predict therapy response. Many studies integrated biomarker programs in their study protocols, thus several potential biomarkers have been identified which are currently under clinical investigation in prospective randomized studies. This review intends to give an overview of the described potential biomarkers as well as different imaging techniques such as ultrasound and magnetic resonance imaging that can indicate benefit, resistance and toxicity to anti-angiogenic therapies.

  4. Optic disc planimetry, corneal hysteresis, central corneal thickness, and intraocular pressure as risk factors for glaucoma.

    Science.gov (United States)

    Carbonaro, Francis; Hysi, Pirro G; Fahy, Samantha J; Nag, Abhishek; Hammond, Christopher J

    2014-02-01

    To determine whether corneal hysteresis and central corneal thickness are independent risk factors for glaucoma. A cross-sectional population-based cohort study. Associations were tested between corneal hysteresis, measured in 1754 population-based subjects from the TwinsUK cohort, and glaucoma-related endophenotypes, including intraocular pressure (IOP), vertical cup-to-disc ratio, optic disc area, and optic disc cup area. Corneal hysteresis, IOP, and central corneal thickness (CCT) were measured; optic disc photographs were analyzed; and multivariable linear regression analysis was performed. Data were available on 1645 individuals. Multiple regression analysis showed corneal hysteresis to be significantly negatively associated with age (beta coefficient = -0.03, P Corneal hysteresis was also found to be associated with CCT (beta coefficient = 0.02, P corneal hysteresis and optic disc area (P = .6), cup area (P = .77), vertical cup-to-disc ratio (P = .51), or spherical equivalent (P = .08). CCT was also found to be significantly associated with IOP (beta coefficient = 3.3, P corneal hysteresis (beta coefficient = 9.4, P corneal hysteresis or CCT and quantitative measures of optic disc cupping, suggesting that corneal hysteresis and CCT are not independent risk factors for glaucoma. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Delayed corneal epithelial wound healing after penetrating keratoplasty in individuals with lattice corneal dystrophy.

    Science.gov (United States)

    Kawamoto, Koji; Morishige, Naoyuki; Yamada, Naoyuki; Chikama, Tai-Ichiro; Nishida, Teruo

    2006-07-01

    To investigate whether corneal epithelial cells of individuals with lattice corneal dystrophy (LCD) possess an intrinsic defect. Retrospective case-control study. The medical charts of nine individuals with LCD and those of 14 patients with keratoconus and 11 patients with corneal leukoma (controls), all of whom underwent penetrating keratoplasty (PKP) in one eye at Yamaguchi University Hospital between February 1998 and November 2001, were examined for the time for epithelial resurfacing after surgery. The time required for resurfacing of the corneal epithelium after PKP was significantly greater in LCD patients (8.56 +/- 4.95 days, mean +/- SD) than in patients with either keratoconus (1.71 +/- 0.91 days, P = .006) or corneal leukoma (3.00 +/- 1.95 days, P = .03). Corneal epithelial wound healing was delayed in LCD patients after PKP, suggesting that the keratoepithelin gene mutations responsible for this condition affect corneal epithelial cells.

  6. Association between corneal hysteresis and central corneal thickness in glaucomatous and non-glaucomatous eyes.

    Science.gov (United States)

    Mangouritsas, George; Morphis, George; Mourtzoukos, Spyridon; Feretis, Elias

    2009-11-01

    We aimed to determine corneal hysteresis values (CH) using the ocular response analyser (ORA) in non-glaucomatous and glaucomatous eyes and their relationship with central corneal thickness (CCT). Corneal hysteresis, intraocular pressure (IOP) as measured by Goldmann applanation tonometry (GAT) and CCT were prospectively evaluated in 74 non-glaucoma subjects with IOP Corneal hysteresis was significantly lower in eyes with treated POAG than in non-glaucomatous eyes. The corneal biomechanical response was strongly associated with CCT in non-glaucoma subjects, but only moderately so in glaucoma patients. It can be assumed that diverse structural factors, in addition to thickness, determine the differences in the corneal biomechanical profile between non-glaucomatous and glaucomatous eyes. Corneal hysteresis could be a useful tool in the diagnosis of glaucoma.

  7. Subconjunctival injection of antagomir-21 alleviates corneal neovascularization in a mouse model of alkali-burned cornea.

    Science.gov (United States)

    Zhang, Yun; Zhang, Ting; Ma, Xiaoyun; Zou, Jun

    2017-02-14

    Corneal neovascularization may result in loss of corneal transparency and blindness. However, developing successful and inexpensive medical treatments for corneal neovascularization remains an unresolved issue. Recently, several studies have implicated miRNA functions in the regulation of cornea homeostasis. This study aimed to identify the miRNA expression profile in the neovascularized cornea after an alkali burn and to investigate the related underlying mechanisms. Here, alkali-burned corneas and matched normal tissues were pooled to perform miRNA sequencing. MiR-21 in alkali-burned cornea showed the greatest increment of abundance at 4 and 7 d after injury compared to the healthy cornea. The miR-21 expression was positively correlated with both the mRNA and protein level of key angiogenic factors including vascular endothelial growth factor (VEGF)-A and hypoxia-inducible factor-1α (HIF-1α). At 2 and 8 d after alkali burn, the mice received subconjunctival injections of antagomir-21 (1 or 5 nmol per injection). The injection of antagomir-21 (5 nmol) inactivated miR-21 and attenuated neovascularization progression by inhibiting the expression of VEGF-A and HIF-1α. Western blot analysis of the corneas demonstrated that antagomir-21 restored Sprouty 2/4 expression and silenced p-ERK activation. Therefore, these data reveal that antagomir-21 ameliorates the progression of corneal neovascularization likely via Sprouty 2/4-mediated inactivation of p-ERK. Delivery of antagomir-21 might be a potential therapeutic approach to prevent or treat visual loss caused by corneal neovascularization.

  8. Finite element modeling of corneal strip extensometry

    CSIR Research Space (South Africa)

    Botha, N

    2012-12-01

    Full Text Available symmetric conicoid [19]: (x xo) 2+(y yo) 2+(1+Q)(z zo) 2 2R(z zo) 2 = 0; (2) c SACAM 2012 25 Top view Isometric view Initial corneal curvature z y x x y z Fig. 3: Finite element model of the vertical corneal strip, including the orthogonal...

  9. Corneal staining after treatment with topical tetracycline

    NARCIS (Netherlands)

    Lapid-Gortzak, Ruth; Nieuwendaal, Carla P.; Slomovic, Allan R.; Spanjaard, Lodewijk

    2006-01-01

    PURPOSE: The purpose of this paper is to report a case of corneal staining after treatment with topical tetracycline. METHODS: A patient with crystalline keratopathy caused by Streptococcus viridans after corneal transplantation was treated topically with tetracycline eye drops, based on results of

  10. Corynebacterium macginleyi isolated from a corneal ulcer

    Directory of Open Access Journals (Sweden)

    Kathryn Ruoff

    2010-02-01

    Full Text Available We report the isolation of Corynebacterium macginleyi from the corneal ulcer culture of a patient, later enrolled in the Steroids for Corneal Ulcer Trial (SCUT. To our knowledge this is the first published report from North America of the recovery of C. macginleyi from a serious ocular infection.

  11. Corneal hysteresis and its relevance to glaucoma

    Science.gov (United States)

    Deol, Madhvi; Taylor, David A.; Radcliffe, Nathan M.

    2015-01-01

    Purpose of review Glaucoma is a leading cause of irreversible blindness worldwide. It is estimated that roughly 60.5 million people had glaucoma in 2010 and that this number is increasing. Many patients continue to lose vision despite apparent disease control according to traditional risk factors. The purpose of this review is to discuss the recent findings with regard to corneal hysteresis, a variable that is thought to be associated with the risk and progression of glaucoma. Recent findings Low corneal hysteresis is associated with optic nerve and visual field damage in glaucoma and the risk of structural and functional glaucoma progression. In addition, hysteresis may enhance intraocular pressure (IOP) interpretation: low corneal hysteresis is associated with a larger magnitude of IOP reduction following various glaucoma therapies. Corneal hysteresis is dynamic and may increase in eyes after IOP-lowering interventions are implemented. Summary It is widely accepted that central corneal thickness is a predictive factor for the risk of glaucoma progression. Recent evidence shows that corneal hysteresis also provides valuable information for several aspects of glaucoma management. In fact, corneal hysteresis may be more strongly associated with glaucoma presence, risk of progression, and effectiveness of glaucoma treatments than central corneal thickness. PMID:25611166

  12. Corneal Biomechanics Determination in Healthy Myopic Subjects

    Science.gov (United States)

    Qiu, Kunliang; Lu, Xuehui; Zhang, Riping; Wang, Geng

    2016-01-01

    Purpose. To determine the corneal biomechanical properties by using the Ocular Response Analyzer™ and to investigate potential factors associated with the corneal biomechanics in healthy myopic subjects. Methods. 135 eyes from 135 healthy myopic subjects were included in this cross-sectional observational study. Cornea hysteresis (CH), corneal resistance factor (CRF), cornea-compensated intraocular pressure (IOPcc), and Goldmann-correlated intraocular pressure (IOPg) were determined with the Reichert Ocular Response Analyzer (ORA). Univariate and multivariate regression analyses were performed to investigate factors associated with corneal biomechanics. Results. The mean CH and CRF were 9.82 ± 1.34 mmHg and 9.64 ± 1.57 mmHg, respectively. In univariate regression analysis, CH was significantly correlated with axial length, refraction, central corneal thickness (CCT), and IOPg (r = −0.27, 0.23, 0.45, and 0.21, resp.; all with p ≤ 0.015), but not with corneal curvature or age; CRF was significantly correlated with CCT and IOPg (r = 0.52 and 0.70, resp.; all with p corneal curvature, or age. In multivariate regression analysis, axial length, IOPcc, and CCT were found to be independently associated with CH, while CCT and IOPg were associated with CRF. Conclusions. Both CH and CRF were positively correlated with CCT. Lower CH but not CRF was associated with increasing degree of myopia. Evaluation of corneal biomechanical properties should take CCT and myopic status into consideration. PMID:27525109

  13. Corneal hysteresis and its relevance to glaucoma.

    Science.gov (United States)

    Deol, Madhvi; Taylor, David A; Radcliffe, Nathan M

    2015-03-01

    Glaucoma is a leading cause of irreversible blindness worldwide. It is estimated that roughly 60.5 million people had glaucoma in 2010 and that this number is increasing. Many patients continue to lose vision despite apparent disease control according to traditional risk factors. The purpose of this review is to discuss the recent findings with regard to corneal hysteresis, a variable that is thought to be associated with the risk and progression of glaucoma. Low corneal hysteresis is associated with optic nerve and visual field damage in glaucoma and the risk of structural and functional glaucoma progression. In addition, hysteresis may enhance intraocular pressure (IOP) interpretation: low corneal hysteresis is associated with a larger magnitude of IOP reduction following various glaucoma therapies. Corneal hysteresis is dynamic and may increase in eyes after IOP-lowering interventions are implemented. It is widely accepted that central corneal thickness is a predictive factor for the risk of glaucoma progression. Recent evidence shows that corneal hysteresis also provides valuable information for several aspects of glaucoma management. In fact, corneal hysteresis may be more strongly associated with glaucoma presence, risk of progression, and effectiveness of glaucoma treatments than central corneal thickness.

  14. Inhibition of Corneal Neovascularization by Hydrazinocurcumin ...

    African Journals Online (AJOL)

    Purpose: To investigate the effect of hydrazinocurcumin on a human vascular endothelial growth factor (VEGF)-induced corneal neovascularization in rabbit model. Methods: Murine corneal neovascularization (CorNV) was induced via two intrastromal implantations of VEGF polymer 2 mm from the limbus.

  15. Corneal plaque containing levofloxacin in a dog.

    Science.gov (United States)

    Park, Young-Woo; Kang, Byung-Jae; Lim, Jae Hyun; Ahn, Jung-Mo; Lim, Hyun Sook

    2015-11-01

    A 13-year-old castrated male Yorkshire terrier developed a corneal ulcer 2 weeks after intracapsular lens extraction (ICLE) in the right eye. The corneal ulcer was treated with levofloxacin eye drops. A plaque with a white luster developed in the central cornea 2 weeks after treatment with levofloxacin eye drops. The corneal plaque was surgically removed under inhalant anesthesia. The corneal plaque displayed antimicrobial activity against Escherichia coli. Furthermore, levofloxacin content in the plaque was confirmed by matrix-assisted laser desorption/ionization time-of-flight/time-of-flight (MALDI-TOF/TOF) mass spectrometry (MS). The corneal ulcer completely resolved 2 weeks after the surgical removal of the corneal lesion and replacement of levofloxacin eye drops with tobramycin eye drops. Although the topical use of levofloxacin is unlikely to lead to corneal chemical deposits due to the high water solubility of the drug compared to other topical fluoroquinolones, this patient developed corneal plaque of the antibiotic drop. © 2015 American College of Veterinary Ophthalmologists.

  16. Corneal laceration caused by river crab

    Directory of Open Access Journals (Sweden)

    Vinuthinee N

    2015-01-01

    Full Text Available Naidu Vinuthinee,1,2 Anuar Azreen-Redzal,1 Jaafar Juanarita,1 Embong Zunaina2 1Department of Ophthalmology, Hospital Sultanah Bahiyah, Alor Setar, 2Department of Ophthalmology, School of Medical Sciences, Universiti Sains Malaysia, Kubang Kerian, Malaysia Abstract: A 5-year-old boy presented with right eye pain associated with tearing and photophobia of 1-day duration. He gave a history of playing with a river crab when suddenly the crab clamped his fingers. He attempted to fling the crab off, but the crab flew and hit his right eye. Ocular examination revealed a right eye corneal ulcer with clumps of fibrin located beneath the corneal ulcer and 1.6 mm level of hypopyon. At presentation, the Seidel test was negative, with a deep anterior chamber. Culture from the corneal scrapping specimen grew Citrobacter diversus and Proteus vulgaris, and the boy was treated with topical gentamicin and ceftazidime eyedrops. Fibrin clumps beneath the corneal ulcer subsequently dislodged, and revealed a full-thickness corneal laceration wound with a positive Seidel test and shallow anterior chamber. The patient underwent emergency corneal toileting and suturing. Postoperatively, he was treated with oral ciprofloxacin 250 mg 12-hourly for 1 week, topical gentamicin, ceftazidime, and dexamethasone eyedrops for 4 weeks. Right eye vision improved to 6/9 and 6/6 with pinhole at the 2-week follow-up following corneal suture removal. Keywords: corneal ulcer, pediatric trauma, ocular injury

  17. Complications from Infective Corneal Conditions Treated by ...

    African Journals Online (AJOL)

    Background: Complications from infective corneal conditions are an important cause of blindness in adults and children. The eyelids play a major role in the pathogenesis of staphyloma and the perforation of descemetoceles. Tarsorrhaphy could, therefore, be beneficial in treating serious complications from infective corneal ...

  18. Facts about the Cornea and Corneal Disease

    Science.gov (United States)

    ... the Cornea and Corneal Disease Facts About the Cornea and Corneal Disease What is the cornea? The cornea is the eye’s outermost layer. It ... your vision. What are the parts of the cornea? Although the cornea may look clear and seem ...

  19. Corneal ulcers: For the general practitioner

    African Journals Online (AJOL)

    153 CME April 2013 Vol. 31 No. 4. Corneal ulcers: For the general practitioner. A corneal ulcer is a defect in the epithelial layer of the cornea. e general practitioner may play an important role in early management and appropriate referral. Incidence varies and depends on aetiology. S Ballim, MB ChB, Dip Ophth (SA), FC ...

  20. Inhibition of Corneal Neovascularization by Hydrazinocurcumin

    African Journals Online (AJOL)

    Purpose: To investigate the effect of hydrazinocurcumin on a human vascular endothelial growth factor. (VEGF)-induced corneal neovascularization in rabbit model. Methods: Murine corneal neovascularization (CorNV) was induced via two intrastromal implantations of. VEGF polymer 2 mm from the limbus.

  1. Molecular expression in transfected corneal endothelial cells

    Science.gov (United States)

    Wang, Fan; Miao, Zhuang; Lu, Chengwei; Hao, Jilong

    2017-10-01

    To investigate the capability of human corneal endothelial cells serving as immunological cells. Expression of HLA-DP, -DQ, -DR, CD40, CD80, and CD86 was determined by immunohistochemical methods. Meanwhile, purified peripheral blood mononuclear cells were cocultured with human corneal endothelial cells which were pre-treated with and without -IFN respectively, activation of lymphocytes was determined by FACS analysis. In coculture system, T lymphocyte was activated by corneal endothelial cells, HLA-DP, -DQ, -DR and CD40 expression were increased by - IFN induction. Costimulatory molecular CD80 was shown on the endothelial cells. Human corneal endothelial cells were assumed to be involved in the corneal transplantation rejection process as potential antigen presenting cells.

  2. Ocular Immune Privilege and Ocular Melanoma: Parallel Universes or Immunological Plagiarism?

    Directory of Open Access Journals (Sweden)

    Jerry Y. Niederkorn

    2012-06-01

    Full Text Available Evidence of immune privilege in the eye was recorded almost 140 years ago, yet interest in immune privilege languished for almost a century. However, the past 35 years have witnessed a plethora of research and a rekindled interest in the mechanisms responsible for immune privilege in the anterior chamber of the eye. This research has demonstrated that multiple anatomical, structural, physiological, and immunoregulatory processes contribute to immune privilege and remind us of the enormous complexity of this phenomenon. It is widely accepted that immune privilege is an adaptation for reducing the risk of immune-mediated inflammation in organs such as the eye and brain whose tissues have a limited capacity to regenerate. Recent findings suggest that immune privilege also occurs in sites where stem cells reside and raise the possibility that immune privilege is also designed to prevent the unwitting elimination of stem cells by immune-mediated inflammation at these sites. Uveal melanoma arises within the eye and as such, benefits from ocular immune privilege. A significant body of research reveals an intriguing parallel between the mechanisms that contribute to immune privilege in the eye and those strategies used by uveal melanoma cells to evade immune elimination once they have disseminated from the eye and establish metastatic foci in the liver. Uveal melanoma metastases seem to have plagiarized the blueprints used for ocular immune privilege to create ad hoc immune privileged sites in the liver.

  3. Ocular immune privilege and ocular melanoma: parallel universes or immunological plagiarism?

    Science.gov (United States)

    Niederkorn, Jerry Y

    2012-01-01

    Evidence of immune privilege in the eye was recorded almost 140 years ago, yet interest in immune privilege languished for almost a century. However, the past 35 years have witnessed a plethora of research and a rekindled interest in the mechanisms responsible for immune privilege in the anterior chamber of the eye. This research has demonstrated that multiple anatomical, structural, physiological, and immunoregulatory processes contribute to immune privilege and remind us of the enormous complexity of this phenomenon. It is widely accepted that immune privilege is an adaptation for reducing the risk of immune-mediated inflammation in organs such as the eye and brain whose tissues have a limited capacity to regenerate. Recent findings suggest that immune privilege also occurs in sites where stem cells reside and raise the possibility that immune privilege is also designed to prevent the unwitting elimination of stem cells by immune-mediated inflammation at these sites. Uveal melanoma arises within the eye and as such, benefits from ocular immune privilege. A significant body of research reveals an intriguing parallel between the mechanisms that contribute to immune privilege in the eye and those strategies used by uveal melanoma cells to evade immune elimination once they have disseminated from the eye and establish metastatic foci in the liver. Uveal melanoma metastases seem to have "plagiarized" the blueprints used for ocular immune privilege to create "ad hoc immune privileged sites" in the liver.

  4. Corneal biomechanical properties in thyroid eye disease

    Directory of Open Access Journals (Sweden)

    Gamze Ozturk Karabulut

    2014-06-01

    Full Text Available The purpose of this study is to investigate the effect of thyroid eye disease (TED on the measurement of corneal biomechanical properties and the relationship between these parameters and disease manifestations. A total of 54 eyes of 27 individuals with TED and 52 eyes of 30 healthy control participants were enrolled. Thyroid ophthalmopathy activity was defined using the VISA (vision, inflammation, strabismus, and appearance/exposure classification for TED. The intraocular pressure (IOP measurement with Goldmann applanation tonometer (GAT, axial length (AL, keratometry, and central corneal thickness (CCT measurements were taken from each patient. Corneal biomechanical properties, including corneal hysteresis (CH and corneal resistance factor (CRF and noncontact IOP measurements, Goldmann-correlated IOP (IOPg and corneal-compensated IOP (IOPcc were measured with the Ocular Response Analyzer (ORA using the standard technique. Parameters such as best corrected visual acuity, axial length, central corneal thickness, and corneal curvature were not statistically significant between the two groups (p > 0.05. IOP measured with GAT was higher in participants with TED (p < 0.001. The CH of TED patients was significantly lower than that of the control group. There was no significant difference in the corneal resistance factor between groups. However, IOPg and IOPcc were significantly higher in TED patients. CH and VISA grading of TED patients showed a negative correlation (p = 0.007. In conclusion, TED affects the corneal biomechanical properties by decreasing CH. IOP with GAT and IOPg is found to be increased in these patients. As the severity of TED increases, CH decreases in these patients.

  5. Corneal manifestations of ocular demodex infestation.

    Science.gov (United States)

    Kheirkhah, Ahmad; Casas, Victoria; Li, Wei; Raju, Vadrevu K; Tseng, Scheffer C G

    2007-05-01

    To report the corneal manifestations in eyes with Demodex infestation of the eyelids. Noncomparative, interventional case series. This retrospective review included six patients with Demodex blepharitis who also exhibited corneal abnormalities, which led to suspicion of limbal stem cell deficiency in three cases. All patients received weekly lid scrubs with 50% tea tree oil and a daily lid scrubs with tea tree shampoo for a minimum of six weeks. Improvement of symptoms and corneal and conjunctival signs were evaluated. All six patients exhibited ocular irritation and conjunctival inflammation, while meibomian gland dysfunction (n = 5), rosacea (n = 4), and decreased vision (n = 3) also were noted despite prior treatments with oral tetracycline, topical steroids with antibiotics, and lid scrub with baby shampoo. These patients were proven to have Demodex folliculorum (n = 6) and Demodex brevis (n = 3) by microscopic examination of epilated lashes. Their corneal manifestation included superficial corneal vascularization (six eyes of five cases), marginal corneal infiltration (two eyes of two cases), phlyctenule-like lesion (one eye of one case), superficial corneal opacity (two eyes of two cases), and nodular corneal scar (two eyes of two cases). After treatment, the Demodex count was reduced from 6.8 +/- 2.8 to 1 +/- 0.9 (standard deviation; P = .001). All patients showed dramatic resolution of ocular irritation, conjunctival inflammation, and all inflammatory, but not scarred, corneal signs; three patients showed improved vision. A variety of corneal pathologic features together with conjunctival inflammation, commonly noted in rosacea, can be found in patients with Demodex infestation of the eyelids. When conventional treatments for rosacea fail, one may consider lid scrub with tea tree oil to eradicate mites as a new treatment.

  6. A theory of biological relativity: no privileged level of causation.

    Science.gov (United States)

    Noble, Denis

    2012-02-06

    Must higher level biological processes always be derivable from lower level data and mechanisms, as assumed by the idea that an organism is completely defined by its genome? Or are higher level properties necessarily also causes of lower level behaviour, involving actions and interactions both ways? This article uses modelling of the heart, and its experimental basis, to show that downward causation is necessary and that this form of causation can be represented as the influences of initial and boundary conditions on the solutions of the differential equations used to represent the lower level processes. These insights are then generalized. A priori, there is no privileged level of causation. The relations between this form of 'biological relativity' and forms of relativity in physics are discussed. Biological relativity can be seen as an extension of the relativity principle by avoiding the assumption that there is a privileged scale at which biological functions are determined.

  7. The movers and shapers in immune privilege of the CNS.

    Science.gov (United States)

    Engelhardt, Britta; Vajkoczy, Peter; Weller, Roy O

    2017-02-01

    Discoveries leading to an improved understanding of immune surveillance of the central nervous system (CNS) have repeatedly provoked dismissal of the existence of immune privilege of the CNS. Recent rediscoveries of lymphatic vessels within the dura mater surrounding the brain, made possible by modern live-cell imaging technologies, have revived this discussion. This review emphasizes the fact that understanding immune privilege of the CNS requires intimate knowledge of its unique anatomy. Endothelial, epithelial and glial brain barriers establish compartments in the CNS that differ strikingly with regard to their accessibility to immune-cell subsets. There is a unique system of lymphatic drainage from the CNS to the peripheral lymph nodes. We summarize current knowledge on the cellular and molecular mechanisms involved in immune-cell trafficking and lymphatic drainage from the CNS, and we take into account differences in rodent and human CNS anatomy.

  8. Price or Privilege? Customer Perception on Loyalty Programs

    Directory of Open Access Journals (Sweden)

    Asnan Furinto

    2011-12-01

    Full Text Available The main purpose of the research is to understand how customers perceive loyalty programs. The author argues that types of loyalty programs could be classified into two: price based and privilege based. This research models that customer perceptions on loyalty programs, differ between these two types, and is contingent upon the relationship between customers and firm. Using settings of air-line domestic passengers and bank customers in Indonesia, the research provides evidence that price based rewards are perceived to provide higher utility perception in contractual relationships compared to non contractual relationships. However, this research failed to provide empirical support that privilege based rewards are perceived to provide higher utility perception in non contractual relation-ship compared to contractual relationship. Firms are therefore, encouraged to incorporate affective elements into their loyalty programs, on top of monetary elements, in order for the loyalty programs to be better perceived by their customers.

  9. Influence of corneal hydration on optical coherence elastography

    Science.gov (United States)

    Twa, Michael D.; Vantipalli, Srilatha; Singh, Manmohan; Li, Jiasong; Larin, Kirill V.

    2016-03-01

    Corneal biomechanical properties are influenced by several factors, including intraocular pressure, corneal thickness, and viscoelastic responses. Corneal thickness is directly proportional to tissue hydration and can influence corneal stiffness, but there is no consensus on the magnitude or direction of this effect. We evaluated the influence of corneal hydration on dynamic surface deformation responses using optical coherence elastography (OCE). Fresh rabbit eyes (n=10) were prepared by removing the corneal epithelium and dropping with 0.9% saline every 5 minutes for 1 hour, followed by 20% dextran solution every 5 minutes for one hour. Corneal thickness was determined from structural OCT imaging and OCE measurements were performed at baseline and every 20 minutes thereafter. Micron-scale deformations were induced at the apex of the corneal tissue using a spatially-focused (150μm) short-duration (corneal thickness due to hydration process. Corneal thickness rapidly increased and remained constant following epithelium removal and changed little thereafter. Likewise, corneal stiffness changed little over the first hour and then decreased sharply after Dextran application (thickness: -46% [-315/682 μm] RR: - 24% [-0.7/2.88 ms-1]; GV: -19% [-0.6/3.2 m/s]). Corneal thickness and corneal stiffness (RR) were well correlated (R2 = .66). Corneal biomechanical properties are highly correlated with tissue hydration over a wide range of corneal thickness and these changes in corneal stiffness are quantifiable using OCE.

  10. Corneal Regeneration by Deep Anterior Lamellar Keratoplasty (DALK Using Decellularized Corneal Matrix.

    Directory of Open Access Journals (Sweden)

    Yoshihide Hashimoto

    Full Text Available The purpose of this study is to demonstrate the feasibility of DALK using a decellularized corneal matrix obtained by HHP methodology. Porcine corneas were hydrostatically pressurized at 980 MPa at 10°C for 10 minutes to destroy the cells, followed by washing with EGM-2 medium to remove the cell debris. The HHP-treated corneas were stained with H-E to assess the efficacy of decellularization. The decellularized corneal matrix of 300 μm thickness and 6.0 mm diameter was transplanted onto a 6.0 mm diameter keratectomy wound. The time course of regeneration on the decellularized corneal matrix was evaluated by haze grading score, fluorescein staining, and immunohistochemistry. H-E staining revealed that no cell nuclei were observed in the decellularized corneal matrix. The decellularized corneal matrices were opaque immediately after transplantation, but became completely transparent after 4 months. Fluorescein staining revealed that initial migration of epithelial cells over the grafts was slow, taking 3 months to completely cover the implant. Histological sections revealed that the implanted decellularized corneal matrix was completely integrated with the receptive rabbit cornea, and keratocytes infiltrated into the decellularized corneal matrix 6 months after transplantation. No inflammatory cells such as macrophages, or neovascularization, were observed during the implantation period. The decellularized corneal matrix improved corneal transparency, and remodelled the graft after being transplanted, demonstrating that the matrix obtained by HHP was a useful graft for corneal tissue regeneration.

  11. High interocular corneal symmetry in average simulated keratometry, central corneal thickness, and posterior elevation.

    Science.gov (United States)

    Myrowitz, Elliott H; Kouzis, Anthony C; O'Brien, Terrence P

    2005-05-01

    The purpose of this study was to assess interocular corneal symmetry in average simulated keratometry, corneal thickness, and posterior corneal elevation. This retrospective analysis included data from scanning slit topography (Orbscan II; Bausch and Lomb, Rochester, NY) on 242 eyes from 121 consecutive patients undergoing standard evaluation for consideration of elective laser vision correction. The symmetry between the right and left eye in average simulated keratometry, minimum central corneal thickness, and posterior corneal elevation was assessed by comparative data analysis. Simulated keratometry ranged from 39.9 to 48.6 D. The interocular difference in average simulated keratometry was 0.47 D (standard deviation [SD] 0.43). The interocular Pearson correlation coefficient for average simulated keratometry was 0.90 (p central corneal thickness was 0.95 (p symmetry in all these parameters was very high in this group of consecutive patients. Asymmetry of these interocular parameters may warrant repeat clinical testing for accuracy and may predict corneal abnormalities. Normative data on posterior cornea elevation is presented. This study points out potentially clinically important high interocular corneal symmetry data in simulated keratometry, corneal thickness, and posterior corneal elevation.

  12. Corneal epithelium following penetrating keratoplasty.

    Science.gov (United States)

    Tsubota, K; Mashima, Y; Murata, H; Yamada, M; Sato, N

    1995-03-01

    This study was designed to observe any changes to the corneal epithelium after penetrating keratoplasty. The corneal epithelia of 26 patients were observed by specular microscopy 1 week, 1 month, 3 months, and 6 months following penetrating keratoplasty. After re-epithelialisation was confirmed by biomicroscopy 1 week after surgery, specular microscopy revealed many abnormal cells, including spindle shaped cells, nucleated cells, large cells, as well as irregular cell configurations. Although these abnormal findings tended to decrease with time, they were still present in some cases as much as 6 months postoperatively. Computerised morphometric analysis yielded mean cell areas of 1121 (SD 168) microns 2, 1139 (675) microns 2, 1712 (496) microns 2, and 1400 (377) microns 2 at 1 week, 1 month, 3 months, and 6 months respectively, all significantly greater than that of age matched controls (710 (151) microns 2). The shape factor decreased with time, but was still greater than the control level at 6 months. This study demonstrates that epithelial abnormalities persist longer than expected after penetrating keratoplasty, and that these subtle changes can be detected by specular microscopic observation, potentially allowing for modification and enhancement of the wound healing process.

  13. Intrastromal corneal ring implants for corneal thinning disorders: an evidence-based analysis.

    Science.gov (United States)

    2009-01-01

    The purpose of this project was to determine the role of corneal implants in the management of corneal thinning disease conditions. An evidence-based review was conducted to determine the safety, effectiveness and durability of corneal implants for the management of corneal thinning disorders. The evolving directions of research in this area were also reviewed. SUBJECT OF THE EVIDENCE-BASED ANALYSIS: The primary treatment objectives for corneal implants are to normalize corneal surface topography, improve contact lens tolerability, and restore visual acuity in order to delay or defer the need for corneal transplant. Implant placement is a minimally invasive procedure that is purported to be safe and effective. The procedure is also claimed to be adjustable, reversible, and both eyes can be treated at the same time. Further, implants do not limit the performance of subsequent surgical approaches or interfere with corneal transplant. The evidence for these claims is the focus of this review. The specific research questions for the evidence review were as follows: SafetyCorneal Surface Topographic Effects:Effects on corneal surface remodellingImpact of these changes on subsequent interventions, particularly corneal transplantation (penetrating keratoplasty [PKP])Visual AcuityRefractive OutcomesVISUAL QUALITY (SYMPTOMS): such as contrast vision or decreased visual symptoms (halos, fluctuating vision)Contact lens toleranceFunctional visual rehabilitation and quality of lifePatient satisfaction:Disease Process:Impact on corneal thinning processEffect on delaying or deferring the need for corneal transplantation TARGET POPULATION AND CONDITION Corneal ectasia (thinning) comprises a range of disorders involving either primary disease conditions such as keratoconus and pellucid marginal corneal degeneration or secondary iatrogenic conditions such as corneal thinning occurring after LASIK refractive surgery. The condition occurs when the normally round dome-shaped cornea

  14. Current treatment options for corneal ectasia.

    Science.gov (United States)

    Tan, Donald T H; Por, Yong-Ming

    2007-07-01

    The approach to the management of various forms of corneal ectasia is changing, with the advent of new surgical and nonsurgical options. The purpose of this review is to summarize and evaluate relevant studies on new treatments for keratoconus, postrefractive surgery keratectasia, and peripheral ectatic corneal disorders. Various alternatives to corneal transplantation for the management of keratoconus aim to enhance corneal rigidity by means of nonsurgical collagen cross-linking, or with the use of intrastromal corneal ring segments, and studies suggest that these treatments may reduce astigmatism or ectatic progression to varying degrees. Recent developments in anterior lamellar keratoplasty enable targeted replacement or augmentation of corneal stroma without replacement of endothelium, and include procedures such as deep anterior lamellar keratoplasty, microkeratome or laser-assisted anterior lamellar surgery, and peripheral tectonic lamellar keratoplasty procedures demonstrate successful reinforcement of peripheral stroma to reduce astigmatism. These new forms of surgery are viable alternatives to conventional penetrating keratoplasty and bring added safety profiles for long-term visual rehabilitation and restoration of tectonic integrity in central and peripheral forms of corneal ectasia.

  15. Factors Affecting Corneal Hysteresis in Taiwanese Adults.

    Science.gov (United States)

    Wang, Jia-Kang; Huang, Tzu-Lun; Pei-Yuan Su; Chang, Pei-Yao

    2015-09-01

    To investigate the correlation of various corneal hysteresis (CH) factors in Chinese adults. From January 2009 to November 2011, the healthy right eyes of a total of 292 adults were recruited into the study. Goldmann-correlated intraocular pressure (IOPG) and CH were measured using an ocular response analyzer (ORA). Central corneal thickness was measured using the ORA's integrated handheld ultrasonic pachymeter. The IOLMaster was used to obtain the ocular biometric measurements including axial length, anterior chamber depth, and keratometric values. The Pearson correlation coefficient was used to test correlations between CH and quantitative factors. The chi-square test was used to detect differences in categorical values. Longer axial length (P = 0.0001), lower IOPG (P = 0.03), older age (P = 0.003), and thinner central corneal thickness (P = 0.0001) were significantly associated with lower CH. The anterior chamber depth (P = 0.34), gender (P = 0.23), and corneal curvature (P = 0.18) had no relationship to CH. Various factors including axial length, intraocular pressure, age, and central corneal thickness can affect measurement of corneal biomechanical properties in Chinese adults. But the anterior chamber depth, gender, and corneal curvature were irrelevant to CH.

  16. Analysis of ethanol effects on corneal epithelium.

    Science.gov (United States)

    Oh, Joo Youn; Yu, Ji Min; Ko, Jung Hwa

    2013-06-04

    Ethanol is widely used in ocular surface surgeries and for the treatment of corneal diseases. However, ethanol is a toxic agent that is related to the development of a number of alcohol-related diseases. Despite the common use of ethanol for therapeutic purposes in ophthalmology, effects of ethanol on the ocular surface have been poorly defined. Hence, we performed this study to investigate effects of ethanol on corneal epithelium from various aspects. We exposed corneal epithelial cells in culture to different concentrations of ethanol for 30 seconds and evaluated the cells for toxicity, survival, and expression of cell-specific markers and inflammatory cytokines at 24, 48, and 72 hours after ethanol exposure. We found that ethanol markedly decreased the viability of cells in a concentration-dependent manner by causing cell lysis, suppressing proliferation, and inducing apoptosis. Also, expression of corneal epithelial cell-specific markers, both stem cell and differentiation markers, was significantly reduced by ethanol exposure. Expression of proinflammatory cytokines and chemokines was highly increased in corneal epithelial and stromal cells that were exposed to ethanol. Together, data suggest that brief exposure of the corneal surface to ethanol may have long-term effects by disrupting the integrity of corneal epithelium and generating inflammation, both of which are precursors to a number of ocular surface diseases.

  17. Electrospun Scaffolds for Corneal Tissue Engineering: A Review

    OpenAIRE

    Bin Kong; Shengli Mi

    2016-01-01

    Corneal diseases constitute the second leading cause of vision loss and affect more than 10 million people globally. As there is a severe shortage of fresh donated corneas and an unknown risk of immune rejection with traditional heterografts, it is very important and urgent to construct a corneal equivalent to replace pathologic corneal tissue. Corneal tissue engineering has emerged as a practical strategy to develop corneal tissue substitutes, and the design of a scaffold with mechanical pro...

  18. Current concepts and techniques in corneal transplantation.

    Science.gov (United States)

    Laibson, Peter R

    2002-08-01

    The corneal endothelium is the most important single layer in corneal transplantation. In his Castroviejo Lecture, William Bourne, MD, summarizes his work on the corneal endothelium and its importance to corneal transplantation. Almost half the corneal transplants performed in the United States are done so because of malfunctioning, diseased, or absent endothelial cells. If just this layer could be transplanted, the long wait for better vision after keratoplasty (up to two years in some countries) can be eliminated, as well as the problems of epithelial and subepithelial graft rejection. The significant astigmatism after keratoplasty could also be reduced. Transplantation of the endothelium in deep lamellar keratoplasty is being done in limited fashion throughout the world and the first patients have now been done in the United States. In many countries where corneal tissue is difficult to obtain, keratoplasty is only performed on one eye, even though both eyes may need it. One article this year discusses binocular vision recovery in bilateral keratoplasty and the objective and subjective improvements after bilateral keratoplasty. Patients who are bilaterally blind from diseases such as Stevens-Johnson syndrome, and ocular pemphigoid have little hope of visual recovery from conventional corneal transplants. The use of a keratoprosthesis to bypass the totally abnormal conjunctival surface has helped many people in the past. The preoperative prognostic categories of patients who may benefit from keratoprosthesis has been carefully reviewed in a large number of keratoprosthesis patients and this information will help ophthalmologists decide who will benefit the most benefit from keratoprosthesis. This year, articles on corneal transplantation after conjunctival flaps, suture-related complications in keratoplasty, the implantation of an intraocular lens after penetrating keratoplasty, and long-term results of penetrating keratoplasty with glaucoma drainage tube

  19. Corneal Biomechanical Properties in Rheumatoid Arthritis.

    Science.gov (United States)

    Can, Mehmet Erol; Erten, Sukran; Can, Gamze Dereli; Cakmak, Hasan Basri; Sarac, Ozge; Cagil, Nurullah

    2015-11-01

    To investigate the variations in biomechanical properties of the cornea in rheumatoid arthritis (RA) patients. A total of 53 RA patients, and 25 healthy individuals (control group) were enrolled. Rheumatoid arthritis patients were classified as in active phase (group 1; n=24) or in remission phase (group 2; n=29). Corneal biomechanical parameters including corneal hysteresis (CH), corneal resistance factor (CRF), corneal compensated intraocular pressure (IOPcc), and Goldmann-correlated IOP (IOPg) were measured with the Reichert Ocular Response Analyzer. Topographical measurements, including central corneal thickness (CCT), anterior chamber depth, iridocorneal angle, and corneal volume were measured using a Sirius corneal topographer. The mean CH was 9.43±1.17 mm Hg in group 1, 9.42±1.84 mm Hg in group 2, and 10.47±1.68 mm Hg in the control group (P=0.03). The mean IOPcc was 17.85±3.2 mm Hg in group 1, 17.95±3.49 mm Hg in group 2, and 15.36±3.11 mm Hg in the control group (P=0.008). The CH showed a significant positive correlation with CRF (P=0.000, r=0.809) and CCT (P=0.000, r=0.461), and a significant negative correlation with IOPcc (P=0.000, r=-0.469). Decrease in the mean CH measurements indicates that ultrastructural changes in the cornea may occur in the active phase, and these changes persist in the remission period. In addition, IOPcc is significantly affected by the corneal biomechanical properties. In RA patients, it is important to control the corneal parameters and IOP measurements against the irreversible changes on the optic nerve.

  20. Perforated Gastric Ulcer Associated with Anti-Angiogenic Therapy

    Directory of Open Access Journals (Sweden)

    Diogo Libânio

    2017-08-01

    Full Text Available Anti-angiogenic therapy with bevacizumab, an inhibitor of vascular endothelial growth factor, is commonly used in metastatic colorectal cancer and is rarely associated with gastrointestinal perforation, perforation being more frequent in the primary tumor site or at the anastomotic level. We present the case of a 64-year-old male with stage IV rectal adenocarcinoma who was on palliative chemotherapy with FOLFOX and bevacizumab. After the 4th chemotherapy cycle, our patient started fever and epigastric pain. He was hemodynamically stable, and signs of peritoneal irritation were absent. There were no alterations in the abdominal X-ray, and C-reactive protein was markedly elevated. A CT scan revealed a de novo thickness in the gastric antrum. Upper digestive endoscopy showed an ulcerated 40-mm lesion in the angulus, with a 20-mm orifice communicating with an exsudative cavity revested by the omentum. A conservative approach was decided including fasting, broad-spectrum intravenous antibiotics, and proton-pump inhibitors. Subsequent gastroduodenal series showed no contrast extravasation, allowing the resumption of oral nutrition. Esophagogastroduodenoscopy after 8 weeks showed perforation closure. Biopsies did not show neoplastic cells or Heliobacter pylori infection. Although the success in the conservative management of perforation allowing the maintenance of palliative chemotherapy (without bevacizumab, the patient died after 4 months due to liver failure. The reported case shows an uncommon endoscopic finding due to a rare complication of anti-angiogenic therapy. Additionally, it reminds clinicians that a history of gastroduodenal ulcers should be actively sought before starting anti-angiogenic treatment and that suspicion for perforation should be high in these cases.

  1. Hypoxia enhances the angiogenic potential of human dental pulp cells.

    Science.gov (United States)

    Aranha, Andreza M F; Zhang, Zhaocheng; Neiva, Kathleen G; Costa, Carlos A S; Hebling, Josimeri; Nör, Jacques E

    2010-10-01

    Trauma can result in the severing of the dental pulp vessels, leading to hypoxia and ultimately to pulp necrosis. Improved understanding of mechanisms underlying the response of dental pulp cells to hypoxic conditions might lead to better therapeutic alternatives for patients with dental trauma. The purpose of this study was to evaluate the effect of hypoxia on the angiogenic response mediated by human dental pulp stem cells (DPSCs) and human dental pulp fibroblasts (HDPFs). DPSCs and HDPFs were exposed to experimental hypoxic conditions. Hypoxia-inducible transcription factor-1alpha (HIF-1alpha) was evaluated by Western blot and immunocytochemistry, whereas vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) expression was evaluated by enzyme-linked immunosorbent assay. YC-1, an inhibitor of HIF-1alpha, was used to evaluate the functional effect of this transcriptional factor on hypoxia-induced VEGF expression. Conditioned medium from hypoxic and normoxic pulp cells was used to stimulate human dermal microvascular endothelial cells (HDMECs). HDMEC proliferation was measured by WST-1 assay, and angiogenic potential was evaluated by a capillary sprouting assay in 3-dimensional collagen matrices. Hypoxia enhanced HIF-1alpha and VEGF expression in DPSCs and HDPFs. In contrast, hypoxia did not induce bFGF expression in pulp cells. YC-1 partially inhibited hypoxia-induced HIF-1alpha and VEGF in these cells. The growth factor milieu of hypoxic HDPFs (but not hypoxic DPSCs) induced endothelial cell proliferation and sprouting as compared with medium from normoxic cells. Collectively, these data demonstrate that hypoxia induces complex and cell type-specific pro-angiogenic responses and suggest that VEGF (but not bFGF) participates in the revascularization of hypoxic dental pulps. Copyright © 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  2. Enhanced detection method for corneal protein identification using shotgun proteomics

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    Schlager John J

    2009-06-01

    Full Text Available Abstract Background The cornea is a specialized transparent connective tissue responsible for the majority of light refraction and image focus for the retina. There are three main layers of the cornea: the epithelium that is exposed and acts as a protective barrier for the eye, the center stroma consisting of parallel collagen fibrils that refract light, and the endothelium that is responsible for hydration of the cornea from the aqueous humor. Normal cornea is an immunologically privileged tissue devoid of blood vessels, but injury can produce a loss of these conditions causing invasion of other processes that degrade the homeostatic properties resulting in a decrease in the amount of light refracted onto the retina. Determining a measure and drift of phenotypic cornea state from normal to an injured or diseased state requires knowledge of the existing protein signature within the tissue. In the study of corneal proteins, proteomics procedures have typically involved the pulverization of the entire cornea prior to analysis. Separation of the epithelium and endothelium from the core stroma and performing separate shotgun proteomics using liquid chromatography/mass spectrometry results in identification of many more proteins than previously employed methods using complete pulverized cornea. Results Rabbit corneas were purchased, the epithelium and endothelium regions were removed, proteins processed and separately analyzed using liquid chromatography/mass spectrometry. Proteins identified from separate layers were compared against results from complete corneal samples. Protein digests were separated using a six hour liquid chromatographic gradient and ion-trap mass spectrometry used for detection of eluted peptide fractions. The SEQUEST database search results were filtered to allow only proteins with match probabilities of equal or better than 10-3 and peptides with a probability of 10-2 or less with at least two unique peptides isolated within

  3. Myocardial hypertrophy overrides the angiogenic response to hypoxia.

    Directory of Open Access Journals (Sweden)

    Yeong-Hoon Choi

    Full Text Available Cyanosis and myocardial hypertrophy frequently occur in combination. Hypoxia or cyanosis can be potent inducers of angiogenesis, regulating the expression of hypoxia-inducible factors (HIF, vascular endothelial growth factors (VEGF, and VEGF receptors (VEGFR-1 and 2; in contrast, pressure overload hypertrophy is often associated with impaired pro-angiogenic signaling and decreased myocardial capillary density. We hypothesized that the physiological pro-angiogenic response to cyanosis in the hypertrophied myocardium is blunted through differential HIF and VEGF-associated signaling.Newborn rabbits underwent aortic banding and, together with sham-operated littermates, were transferred into a hypoxic chamber (FiO(2 = 0.12 at 3 weeks of age. Control banded or sham-operated rabbits were housed in normoxia. Systemic cyanosis was confirmed (hematocrit, arterial oxygen saturation, and serum erythropoietin. Myocardial tissue was assayed for low oxygen concentrations using a pimonidazole adduct. At 4 weeks of age, HIF-1alpha and HIF-2alpha protein levels, HIF-1alpha DNA-binding activity, and expression of VEGFR-1, VEGFR-2, and VEGF were determined in hypoxic and normoxic rabbits. At 6 weeks of age, left-ventricular capillary density was assessed by immunohistochemistry. Under normoxia, capillary density was decreased in the banded rabbits compared to non-banded littermates. As expected, non-hypertrophied hearts responded to hypoxia with increased capillary density; however, banded hypoxic rabbits demonstrated no increase in angiogenesis. This blunted pro-angiogenic response to hypoxia in the hypertrophied myocardium was associated with lower HIF-2alpha and VEGFR-2 levels and increased HIF-1alpha activity and VEGFR-1 expression. In contrast, non-hypertrophied hearts responded to hypoxia with increased HIF-2alpha and VEGFR-2 expression with lower VEGFR-1 expression.The participation of HIF-2alpha and VEGFR-2 appear to be required for hypoxia

  4. Sequential plasma angiogenic factors levels in women with suspected preeclampsia.

    Science.gov (United States)

    Baltajian, Kedak; Bajracharya, Surichhya; Salahuddin, Saira; Berg, Anders H; Geahchan, Carl; Wenger, Julia B; Thadhani, Ravi; Karumanchi, S Ananth; Rana, Sarosh

    2016-07-01

    Alterations in circulating angiogenic factors are associated with the diagnosis of preeclampsia and correlate with adverse perinatal outcomes during the third trimester. Analysis of the sequential levels of plasma angiogenic factors among patients admitted for evaluation of preeclampsia. We performed an observational study among women with singleton pregnancies admitted to Beth Israel Deaconess Medical Center, Boston, Massachusetts, for evaluation of preeclampsia at less than 37 weeks of gestation. Plasma samples were collected on admission and daily for the first 3 days and then weekly until delivery. Doppler ultrasound was performed on admission (within 48 hours) and then weekly (within 24 hours of blood collection) to evaluate uteroplacental and umbilical blood flows. Maternal demographics, hospital course, mode of delivery, diagnosis of hypertensive disorder, adverse maternal outcomes (elevated liver function enzymes, low platelet count, pulmonary edema, cerebral hemorrhage, convulsion, acute renal insufficiency, or maternal death), and adverse fetal/neonatal outcomes (small for gestational age, abnormal umbilical artery Doppler, fetal death, and neonatal death) were recorded. Circulating angiogenic factors (soluble fms-like tyrosine kinase and placental growth factor were measured on automated platform in a single batch after delivery and in a blinded fashion. Data are presented as median (25th to 75th centile), mean, or proportions as appropriate. During the study period, data from 100 women were analyzed for the study, and 43 had adverse outcomes. Women with adverse outcomes had lower gestational age of delivery, higher systolic and diastolic blood pressures during hospitalization, and lower birthweight and placental weight (all P preeclampsia, women at risk for adverse pregnancy outcomes have higher soluble fms-like tyrosine kinase/placental growth factor ratio on admission, which continued to rise until delivery. Women with high soluble fms-like tyrosine

  5. Technology needs for corneal transplant surgery

    Science.gov (United States)

    Vaddavalli, Pravin K.; Yoo, Sonia H.

    2011-03-01

    Corneal transplant surgery has undergone numerous modifications over the years with improvements in technique, instrumentation and eye banking. The main goals of corneal transplantation are achieving excellent optical clarity with long-term graft survival. Penetrating, anterior and posterior lamellar surgery along with femtosecond laser technology have partially met these goals, but outcomes are often unpredictable and surgeon dependent. Technology to predictably separate stroma from Descemet's membrane, techniques to minimize endothelial cell loss, improvements in imaging technology and emerging techniques like laser welding that might replace suturing, eventually making corneal transplantation a refractively predictable procedure are on the wish list of the cornea surgeon.

  6. The Effect of Smoking on Corneal Biomechanics.

    Science.gov (United States)

    Kilavuzoglu, Ayse Ebru; Celebi, Ali Riza Cenk; Altiparmak, Ugur Emrah; Cosar, Cemile Banu

    2017-01-01

    To determine the effect of smoking on corneal biomechanical behavior. The medical records of consecutive patients that presented to the ophthalmology department were reviewed. History of smoking and ophthalmological examination findings were recorded. The smoking group met the following criteria: a clear history of and present smoking habit, negative history of corneal disease and surgery, ocular response analyzer measurement at the time of examination, and a waveform score ≥3.7. Nonsmokers (never smoked or quit smoking ≥6 months earlier) that met the same criteria constituted the control group. Corneal biomechanical parameters were measured using ocular response analyzer. Data were analyzed using Pearson's χ(2) test, Mann-Whitney U test, and Spearman's correlation coefficient. The smoking group included 166 eyes of 166 patients with a mean age of 38.7 ± 11.95 years, and the control group consisted of 170 eyes of 170 patients with a mean age of 38.40 ± 12.2 years. Mean cumulative smoking dose in the smoking group was 9.59 ± 11.87 pack-years (0.04- 75.00). There was no significant correlation between cumulative smoking dose and corneal hysteresis and corneal resistance factor (P = 0.382 and 0.074, respectively). There were no significant differences in corneal hysteresis or the corneal resistance factor between the two groups (P > 0.05). There was no significant difference in corneal hysteresis between those in the smoking group aged 18-44 years and those aged 45-64 years (P = 0.258), whereas in the control group mean corneal hysteresis was significantly lower in the 45-64 year olds than in the 18-44 year olds (P = 0.034). Although there was no significant difference in corneal biomechanics between smoking and control groups, the decrease in corneal hysteresis with aging was less apparent in the smoking group, which may be due to the potential changes in the cornea's microstructure induced by smoking during aging and the effect of smoking in aged corneal

  7. Should nylon corneal sutures be routinely removed?

    Science.gov (United States)

    Jackson, H.; Bosanquet, R.

    1991-01-01

    Three groups of patients who had undergone cataract extraction through a corneal incision closed with 10/0 nylon sutures one, two, and three years previously were recalled to determine the incidence of suture related complications. Broken corneal sutures were found in 87.5% of patients after two years and 90% after three years and were causing symptoms in over half the patients. It is recommended that 10/0 nylon corneal sutures be routinely removed no later than one year after surgery. Images PMID:1751460

  8. Clinical study on human lamellar keratoplasty for fungal corneal ulcers with porcine acellular corneal stroma

    OpenAIRE

    Fu-Hong Liao; Zi-Zhong Yu; Bin Hu

    2017-01-01

    AIM: To observe the transplantation of acellular porcine corneal stroma on the treatment of superficial keratitis by drug-resistant fungal. METHODS: We performed a retrospective analysis of 16 cases of fungal keratitis received the transplantation of acellular porcine corneal matrix from June 2015 to March 2016 with a follow-up of 6mo. We analyzed on items as postoperative visual acuity, corneal graft status, postoperative recurrence and postoperative complications. RESULTS: We observed a hea...

  9. Corneal-Wavefront guided transepithelial photorefractive keratectomy after corneal collagen cross linking in keratoconus

    OpenAIRE

    Camellin, Massimo; Guidotti, Jacopo Maria; Arba Mosquera, Samuel

    2016-01-01

    Purpose To evaluate the efficacy and safety of Corneal-Wavefront guided transepithelial photorefractive keratectomy (TransPRK) after corneal collagen cross linking (CXL) in keratoconic patients. Methods In this retrospective, non-comparative, consecutive case series, 39 keratoconic eyes underwent Corneal-Wavefront guided TransPRK for the correction of aberrations at least 4 months after conventional CXL at SEKAL Rovigo Microsurgery Centre, Rovigo, Italy. Two eyes (5%) underwent a secondary la...

  10. Role of Corneal Epithelium in Riboflavin/Ultraviolet-A Mediated Corneal Cross-Linking Treatment in Rabbit Eyes

    OpenAIRE

    Xiangchen Tao; Haiqun Yu; Yong Zhang; Zhiwei Li; Vishal Jhanji; Shouxiang Ni; Ya Wang; Guoying Mu

    2013-01-01

    Purpose. To evaluate the role of corneal epithelium in riboflavin/ultraviolet-A (UVA) mediated corneal collagen cross-linking treatment. Methods. Fifty New Zealand rabbits were divided into 5 groups: UVA treatment with or without corneal epithelium, UVA+riboflavin treatment with or without corneal epithelium, and control without any treatment. All rabbits were sacrificed after irradiation and subsequently 4?mm???10?mm corneal strips were harvested for biomechanical evaluation. Results. UVA ir...

  11. Clinical assessment of the soft corneal contact lens on corneal epithelium defect after vitrectomy

    Directory of Open Access Journals (Sweden)

    Meng-Su Tang

    2017-03-01

    Full Text Available AIM: To investigate the effect of soft corneal contact lens on the recovery of corneal epithelial defects and the comfort in patients with diabetic retinopathy after vitrectomy. METHODS: Twenty patients(20 eyeswith diabetic retinopathy whose corneal epithelium defected after vitrectomy were randomly divided into 2 groups. The trial group(10 eyesreceived the combination treatment of wearing soft corneal contact lenses and eyedrops to promote corneal epithelial repair, and the control group(10 eyesonly received eyedrops. The corneal epithelial healing time was observed postoperatively. And the scores of the comfort in patients between two groups were compared. RESULTS: The average duration of corneal epithelial defects was 4.1±1.20d in the trial group, and 14.2±6.07d in the control group, which was statistically significant different between the two groups(PP>0.05. CONCLUSION: The soft corneal contact lens could effectively treat patients with corneal epithelial defects after vitrectomy, and improve their comfort.

  12. Correlation of both corneal surfaces in corneal ectasia after myopic LASIK.

    Science.gov (United States)

    Peinado, Teresa Fernández; Piñero, David P; López, Ignacio Alcaraz; Alio, Jorge L

    2011-04-01

    We report a case of corneal ectasia in a 25-year-old man after myopic laser in situ keratomileusis in which a complete characterization of the corneal structure was performed by means of a Scheimpflug photography-based system. The patient presented in the ectatic eye with a subjective refraction of +0.50 to 6.00 × 100°, which with correction gave a visual acuity of 20/25. With the topographic analysis, corneal shapes from both corneal surfaces at the four different quadrants were found to be complementary, maintaining the meniscus-shaped profile of the cornea. This correlation between the anterior and posterior corneal surfaces was also confirmed with an optical tomography evaluation. Corneal biomechanics was also evaluated by means of the Ocular Response Analyzer (Reichert), which confirmed the biomechanical alteration. In summary, biomechanical changes leading to corneal ectasia in this case affected the global corneal structure, inducing alterations in the shape of both anterior and posterior corneal surfaces.

  13. [The effect of cataract and vitreoretinal surgery on central corneal thickness and corneal hysteresis].

    Science.gov (United States)

    Hager, A; Loge, K; Kutschan, A; Wiegand, W

    2008-03-01

    Intraocular irrigating solutions remain for several hours beyond the actual time of surgery in the eye. The irrigating solution ought to resemble biochemically aqueous humor and vitreous and offer protection for sensitive structures of the eye, such as the corneal endothelium. Impairment of the corneal endothelium may lead to corneal oedema and biomechanical alterations of the cornea. 54 eyes after pars-plana vitrectomy (PPV) in elective macular surgery were evaluated by measuring corneal thickness (CCT) using ultrasound pachymetry (20 MHz) and corneal hysteresis (CH) using the ocular response analyser (Reichert Ophthalmic Instruments, Buffalo, NY, USA). Measurements were performed not earlier than 2 weeks prior to surgery and 1 to 3 days after surgery. Results were compared to a control group (n = 39) and to 101 eyes after clear cornea cataract extraction (KAT). The two groups (PPV and KAT) did not differ with respect to age (p = 0.555). Corneal thickness has increased significantly in both groups (p corneal hysteresis decreased significantly postoperatively (p corneal thickness but also by biomechanical parameters such as corneal hysteresis.

  14. Corneal hysteresis, resistance factor, topography, and pachymetry after corneal lamellar flap.

    Science.gov (United States)

    Gatinel, Damien; Chaabouni, Slim; Adam, Pierre-Alexandre; Munck, Jacques; Puech, Michel; Hoang-Xuan, Thanh

    2007-01-01

    To measure prospectively the early changes in corneal hysteresis, topography, and pachymetry after the creation of a stromal flap cut without laser photoablation. A 37-year-old man was referred for a bioptic procedure to correct for compound myopic astigmatism in the left eye. A 159-microm-thick 8x8.5-mm superior hinged flap was created with a mechanical microkeratome in the left cornea. Changes in the corneal hysteresis, corneal resistance factor, Goldmann correlated intraocular pressure (lOP), corneal compensated IOP, anterior and posterior topography, and optical and ultrasound pachymetry were monitored prospectively before and at 1 hour, 1 day, 5 days, and 25 days after flap creation. The right eye served as a control. In the left eye, corneal hysteresis and corneal resistance factor decreased immediately after the flap cut and remained lower than preoperatively at 1 hour, 1 day, 5 days, and 25 days. Corneal compensated IOP varied significantly less than Goldmann correlated IOP in both eyes. Central flattening of the horizontal meridians was observed on the difference topography maps. The values of the left eye posterior best fit sphere increased after the flap cut. Increased central corneal thickness occurred immediately after the flap cut and decreased over time without returning to its preoperative value. The creation of a stromal flap can modify the biomechanical properties of the cornea, including a reduction in corneal hysteresis. The topographic changes were consistent with previously reported cases of flap cut in normal corneas.

  15. Repair of corneal ulcer or perforation using the corneal stromal lenticule

    Directory of Open Access Journals (Sweden)

    Xiao-Feng Hao

    2018-01-01

    Full Text Available AIM: To describe the outcomes of corneal stromal lenticules in repairing of corneal ulcer and/or perforation. METHODS: This was a retrospective chart review of 6 eyes of 6 patients from January to June 2017,who underwent corneal ulcer repair with the corneal, stromal lenticules harvested from femtosecond laser refractive surgery and kept in pure glycerin for use. Three cases of infectious corneal ulcers were bacterial, fungal, and infection with foreign bodies in corneal deep layer, one each. The other 3 were corneal ulcer perforation. Making sure no air bubble between donor graft and Descemet membrane. The mean follow-up time was 3.71±1.56mo(range 1-6mo. RESULTS: All eyes were successfully treated under control of infection without intra-operative complications, and early postoperative evaluation showed a clear graft in all cases. The last follow-up visit showed the mean best corrected visual acuity(VAsignificantly improved after surgery. There was significant difference from 0.48±0.12 to 1.50±0.08(PCONCLUSION: The preliminary results suggest that the use of corneal stromal lenticules may be a safe and effective surgical alternative for corneal ulcer, even though the long-term outcome of the graft needs to be further observed.

  16. Association between culture results of corneal scrapings and culture and histopathology results of corneal tissues in therapeutic keratoplasty.

    Science.gov (United States)

    Das, Sujata; Sharma, Savitri; Priyadarshini, Omega; Sahu, Srikant K; Kar, Sarita; Vemuganti, Geeta K

    2011-09-01

    To correlate the culture results of corneal scrapings with culture and histopathology results of corneal tissues in therapeutic keratoplasty. A retrospective analysis of the culture results of corneal scrapings and corneal tissues of eyes that received therapeutic penetrating keratoplasty at a tertiary eye care center between December 2006 and November 2008 was conducted. As per the preferred practice, those cases that did not respond to appropriate antimicrobial therapy and/or presented with a large infiltrate/perforation received therapeutic keratoplasty. The microbiology and histopathology findings of the corneal tissues were compared. Thirty-eight therapeutic keratoplasties were performed on 36 patients. Although all cases had histopathology and culture of the corneal tissue, corneal scrapings were not performed in 4 cases. Corneal scrapings and corneal tissues were culture-positive in 76% (26 of 34) and 60% (23 of 38) of cases, respectively. In 8 cases, the corneal scrapings and corneal tissues yielded identical organisms, whereas different organisms grew in 4 cases. In 6 cases, the corneal tissues were culture-positive but the corneal scrapings were sterile. In 20 cases, the corneal tissues were culture-positive for fungus and also showed fungal filaments in their corresponding histopathology specimens. Corneal tissue culture can provide additional information in cases undergoing therapeutic keratoplasty. It helps to determine the management of patients after keratoplasty.

  17. Tumour vasculature and angiogenic profile of paediatric pilocytic astrocytoma; is it much different from glioblastoma?

    NARCIS (Netherlands)

    Sie, M.; de Bont, E. S. J. M.; Scherpen, F. J. G.; Hoving, E. W.; den Dunnen, W. F. A.

    2010-01-01

    Aims: Pilocytic astrocytomas are the most frequent brain tumours in children. Because of their high vascularity, this study aimed to obtain insights into potential angiogenic related therapeutic targets in these tumours by characterization of the vasculature and the angiogenic profile. In this study

  18. Current Challenges of Cancer Anti-angiogenic Therapy and the Promise of Nanotherapeutics.

    Science.gov (United States)

    Abdalla, Ahmed M E; Xiao, Lin; Ullah, Muhammad Wajid; Yu, Miao; Ouyang, Chenxi; Yang, Guang

    2018-01-01

    With growing interest in cancer therapeutics, anti-angiogenic therapy has received considerable attention and is widely administered in several types of human cancers. Nonetheless, this type of therapy may induce multiple signaling pathways compared with cytotoxics and lead to worse outcomes in terms of resistance, invasion, metastasis, and overall survival (OS). Moreover, there are important challenges that limit the translation of promising biomarkers into clinical practice to monitor the efficiency of anti-angiogenic therapy. These pitfalls emphasize the urgent need for discovering alternative angiogenic inhibitors that target multiple angiogenic factors or developing a new drug delivery system for the current inhibitors. The great advantages of nanoparticles are their ability to offer effective routes that target the biological system and regulate different vital processes based on their unique features. Limited studies so far have addressed the effectiveness of nanoparticles in the normalization of the delicate balance between stimulating (pro-angiogenic) and inhibiting (anti-angiogenic) factors. In this review, we shed light on tumor vessels and their microenvironment and consider the current directions of anti-angiogenic and nanotherapeutic treatments. To the best of our knowledge, we consider an important effort in the understanding of anti-angiogenic agents (often a small volume of metals, nonmetallic molecules, or polymers) that can control the growth of new vessels.

  19. Current Challenges of Cancer Anti-angiogenic Therapy and the Promise of Nanotherapeutics

    Science.gov (United States)

    Abdalla, Ahmed M.E.; Xiao, Lin; Ullah, Muhammad Wajid; Yu, Miao; Ouyang, Chenxi; Yang, Guang

    2018-01-01

    With growing interest in cancer therapeutics, anti-angiogenic therapy has received considerable attention and is widely administered in several types of human cancers. Nonetheless, this type of therapy may induce multiple signaling pathways compared with cytotoxics and lead to worse outcomes in terms of resistance, invasion, metastasis, and overall survival (OS). Moreover, there are important challenges that limit the translation of promising biomarkers into clinical practice to monitor the efficiency of anti-angiogenic therapy. These pitfalls emphasize the urgent need for discovering alternative angiogenic inhibitors that target multiple angiogenic factors or developing a new drug delivery system for the current inhibitors. The great advantages of nanoparticles are their ability to offer effective routes that target the biological system and regulate different vital processes based on their unique features. Limited studies so far have addressed the effectiveness of nanoparticles in the normalization of the delicate balance between stimulating (pro-angiogenic) and inhibiting (anti-angiogenic) factors. In this review, we shed light on tumor vessels and their microenvironment and consider the current directions of anti-angiogenic and nanotherapeutic treatments. To the best of our knowledge, we consider an important effort in the understanding of anti-angiogenic agents (often a small volume of metals, nonmetallic molecules, or polymers) that can control the growth of new vessels. PMID:29290825

  20. The impact of laser surgery on angiogenic and anti-angiogenic factors in twin-twin transfusion syndrome: a prospective study.

    Science.gov (United States)

    Chon, Andrew H; Chavira, Emiliano R; Wilson, Melissa L; Ingles, Sue A; Llanes, Arlyn; Chmait, Ramen H

    2018-04-01

    To examine the effect of laser surgery on angiogenic and anti-angiogenic factors in patients with twin-twin transfusion syndrome (TTTS). Cases of TTTS and uncomplicated monochorionic diamniotic twin pregnancies between 16 and 26 weeks' gestation were prospectively enrolled into the study. Maternal blood samples were obtained to measure angiogenic factors (vascular endothelial growth factor-A [VEGF], placental-derived growth factor [PlGF], and endothelin) and anti-angiogenic factors (soluble fms-like tyrosine kinase (sFlt-1), soluble endoglin (sEng), and sFlt-1/PlGF ratio). For cases, these factors were measured at visit 1 (pre-operatively), visit 2 (postoperative day one), and visit 3 (at least 3 weeks after surgery). In controls, the factors were measured at visit 1 (enrollment) and visit 2 (at least 3 weeks later). Levels of angiogenic and anti-angiogenic factors between cases and controls were compared. At enrollment, the TTTS cases demonstrated an anti-angiogenic state with significantly higher sFlt-1, sEng, sFlt-1/PlGF ratio, and lower PlGF. Laser surgery, comparing visit 1-3, had a partial corrective effect on TTTS cases. sFlt-1 significantly decreased several weeks after surgery. The other factors (PlGF, endothelin, sFlt-1, sEng, and sFlt-1/PlGF ratio) were not statistically significantly different by visit 3. Laser surgery partially corrected the angiogenic profile in patients with TTTS.

  1. Disrupted Balance of Angiogenic and Antiangiogenic Signalings in Preeclampsia

    Directory of Open Access Journals (Sweden)

    Mitsuko Furuya

    2011-01-01

    Full Text Available The placenta plays a central role in governing local circulatory system that mediates maternal condition and fetal growth. In early gestational phases, the placenta exerts properties of invasion and neovascularization for successful placentation. Extravillous invasive trophoblasts replace uterine endometrial vasculature and establish local blood pathway to obtain oxygen and nutrients from the mother. In later phases, the placenta promotes villous angiogenesis and vascular maturation that are finely controlled by angiogenic and antiangiogenic molecules. Among various molecules involved in placental neovascularization, vascular endothelial growth factor receptors (VEGFRs and angiotensin II receptor type 1 (AT1 mediate important signaling pathways for maternal circulatory system and fetal growth. VEGFR1 and VEGFR2 are functional receptors for placental growth factor (PlGF and VEGF, respectively, and PlGF-VEGFR1 and VEGF-VEGFR2 interactions are disturbed in many preeclamptic patients by excess amount of soluble form of VEGFR1 (also named sFlt1, a natural PlGF/VEGF antagonist. Recent studies have disclosed that excessive sFlt1 production in the placenta and aberrant AT1 signaling in the mother are closely associated with the pathology of preeclampsia and intrauterine growth restriction (IUGR. In this paper, neovascularization of the placenta and pathological events associated with disrupted balance between angiogenic and antiangiogenic signaling in preeclampsia are discussed.

  2. Thrombomodulin promotes corneal epithelial wound healing

    National Research Council Canada - National Science Library

    Huang, Yi-Hsun; I, Ching-Chang; Kuo, Cheng-Hsiang; Hsu, Yun-Yan; Lee, Fang-Tzu; Shi, Guey-Yueh; Tseng, Sung-Huei; Wu, Hua-Lin

    2015-01-01

    To determine the role of thrombomodulin (TM) in corneal epithelial wound healing, and to investigate whether recombinant TM epidermal growth factor-like domain plus serine/threonine-rich domain (rTMD23...

  3. Femtosecond Lasers and Corneal Surgical Procedures.

    Science.gov (United States)

    Marino, Gustavo K; Santhiago, Marcony R; Wilson, Steven E

    2017-01-01

    Our purpose is to present a broad review about the principles, early history, evolution, applications, and complications of femtosecond lasers used in refractive and nonrefractive corneal surgical procedures. Femtosecond laser technology added not only safety, precision, and reproducibility to established corneal surgical procedures such as laser in situ keratomileusis (LASIK) and astigmatic keratotomy, but it also introduced new promising concepts such as the intrastromal lenticule procedures with refractive lenticule extraction (ReLEx). Over time, the refinements in laser optics and the overall design of femtosecond laser platforms led to it becoming an essential tool for corneal surgeons. In conclusion, femtosecond laser is a heavily utilized tool in refractive and nonrefractive corneal surgical procedures, and further technological advances are likely to expand its applications. Copyright 2017 Asia-Pacific Academy of Ophthalmology.

  4. Clear corneal incision in cataract surgery.

    Science.gov (United States)

    Al Mahmood, Ammar M; Al-Swailem, Samar A; Behrens, Ashley

    2014-01-01

    Since the introduction of sutureless clear corneal cataract incisions, the procedure has gained increasing popularity worldwide because it offers several advantages over the traditional sutured scleral tunnels and limbal incisions. Some of these benefits include lack of conjunctival trauma, less discomfort and bleeding, absence of suture-induced astigmatism, and faster visual rehabilitation. However, an increasing incidence of postoperative endophthalmitis after clear corneal cataract surgery has been reported. Different authors have shown a significant increase up to 15-fold in the incidence of endophthalmitis following clear corneal incision compared to scleral tunnels. The aim of this report is to review the advantages and disadvantages of clear corneal incisions in cataract surgery, emphasizing on wound construction recommendations based on published literature.

  5. Corneal biomechanical properties in thyroid eye disease

    National Research Council Canada - National Science Library

    Karabulut, Gamze Ozturk; Kaynak, Pelin; Altan, Cıgdem; Ozturker, Can; Aksoy, Ebru Funda; Demirok, Ahmet; Yılmaz, Omer Faruk

    2014-01-01

    The purpose of this study is to investigate the effect of thyroid eye disease (TED) on the measurement of corneal biomechanical properties and the relationship between these parameters and disease manifestations...

  6. Conjunctival intraepithelial neoplasia with corneal furrow degeneration

    Directory of Open Access Journals (Sweden)

    Pukhraj Rishi

    2014-01-01

    Full Text Available A 68-year-old man presented with redness of left eye since six months. Examination revealed bilateral corneal furrow degeneration. Left eye lesion was suggestive of conjunctival squamous cell carcinoma, encroaching on to cornea. Anterior segment optical coherence tomography (AS-OCT confirmed peripheral corneal thinning. Fluorescein angiography confirmed intrinsic vascularity of lesion. Patient was managed with "no touch" surgical excision, dry keratectomy without alcohol, cryotherapy, and primary closure. Pathologic examination of removed tissue confirmed clinical diagnosis. Management of this particular case required modification of standard treatment protocol. Unlike the alcohol-assisted technique of tumor dissection described, ethyl alcohol was not used for risk of corneal perforation due to underlying peripheral corneal thinning. Likewise, topical steroids were withheld in the post-operative period. Three weeks post-operatively, left eye was healing well. Hence, per-operative usage of absolute alcohol and post-operative use of topical steroids may be best avoided in such eyes.

  7. Surgical compensation of presbyopia with corneal inlays.

    Science.gov (United States)

    Konstantopoulos, Aris; Mehta, Jodhbir S

    2015-05-01

    Presbyopia, the physiological change in near vision that develops with ageing, gradually affects individuals older than 40 years and is a growing cause of visual disability due to ageing demographics of the global population. The routine use of computers and 'smartphones', combined with the affluence of the 'baby boomers' generation has set high standards for near vision correction. Corneal inlays are a relatively new treatment modality that is effective at compensating for presbyopia. The dimensions of these devices vary from 2 to 3.8 mm in diameter and 5 to 32 μm in thickness. They are implanted in the anterior corneal stroma of the non-dominant eye, most commonly, in a femtosecond laser created corneal pocket. They improve near vision by increasing the depth of focus, creating a hyper-prolate region of increased central cornea power or providing a refractive add power. This article reviews the literature on the efficacy and safety of corneal inlays.

  8. [Nanostructured bioplastic material for traumatic corneal injuries].

    Science.gov (United States)

    Kanyukov, V N; Stadnikov, A A; Trubina, O M; Yakhina, O M

    2015-01-01

    To substantiate the use of nanostructured bioplastic material for the treatment of traumatic eye injuries. The study enrolled 96 eyes of 48 rabbits and was carried out in 3 series of experiments, different in the type of induced corneal trauma: mechanical erosion, alkaline or acid burn. The animals were clinically monitored and sacrificed for morphological investigation at days 3, 7, 14, 30, and 90. The size of mechanical corneal erosions was repeatedly evaluated with fluorescein eye stain test. In the experimental group, Hyamatrix biomaterial was topically administered according to an original technique. In the controls, soft contact lenses were inserted and sutured. Complete closure of the epithelial defect with no impact on corneal properties was achieved in 3 days in the experimental group and in4 days in the control group. As for alkaline and acid corneal burns, experimental and control groups received Hyamatrix biomaterial and Solcoseryl eye gel correspondingly. In the experimental group of alkaline burn the defect closed by day 7, in the controls--by day 10-11. Acid-induced corneal edema also resolved by day 7 in the experimental group and by day 14 in the control group. 1. The results of this experimental and morphological study prove the hyaluronic acid-derived nanostructured bioplastic material effective in accelerating corneal re-epithelialization after mechanical erosions as compared with the controls. 2. Topical application of the hyaluronic acid-derived nanostructured bioplastic material shortens the exudative phase of inflammation, promotes corneal defect closure with formation of a more subtle opacification, and stimulates corneal restoration after chemical burns.

  9. IOL Power Calculation after Corneal Refractive Surgery

    OpenAIRE

    Maddalena De Bernardo; Luigi Capasso; Luisa Caliendo; Francesco Paolercio; Nicola Rosa

    2014-01-01

    Purpose. To describe the different formulas that try to overcome the problem of calculating the intraocular lens (IOL) power in patients that underwent corneal refractive surgery (CRS). Methods. A Pubmed literature search review of all published articles, on keyword associated with IOL power calculation and corneal refractive surgery, as well as the reference lists of retrieved articles, was performed. Results. A total of 33 peer reviewed articles dealing with methods that try to overcome the...

  10. Corneal collagen crosslinking for keratoconus. A review

    OpenAIRE

    M. M. Bikbov; V. K. Surkova

    2014-01-01

    Photochemical crosslinking is widely applied in ophthalmology. Its biochemical effect is due to the release of singlet oxygen that promotes anaerobic photochemical reaction. Keratoconus is one of the most common corneal ectasia affecting 1 in 250 to 250 000 persons. Currently, the rate of iatrogenic ectasia following eximer laser refractive surgery increases due to biomechanical weakening of the cornea. Morphologically and biochemically, ectasia is characterized by corneal layers thinning, co...

  11. Corneal biomechanical properties of patients with acromegaly.

    Science.gov (United States)

    Ozkok, Ahmet; Hatipoglu, Esra; Tamcelik, Nevbahar; Balta, Burcu; Gundogdu, Ahmet Sadi; Ozdamar, Mehmet Akif; Kadioglu, Pinar

    2014-05-01

    Growth hormone (GH) and insulin-like growth factor-1 (IGF-1) excess in acromegaly have various effects on many organs. The ophthalmologic effects of GH and IGF-1 excess have not yet been investigated in detail. The aim of the current study is to compare the corneal biomechanical properties of patients with acromegaly and those of healthy subjects. 45 patients with acromegaly (F/M=27/18) and 42 age-matched and gender-matched healthy individuals (F/M=24/18) were enrolled in this cross-sectional study. Central corneal thickness (CCT), corneal resistance factor (CRF), corneal hysteresis (CH), corneal compensated intraocular pressure (IOPcc) and Goldmann correlated IOPG were measured in patients with acromegaly and in healthy individuals using the Ocular Response Analyser (ORA). GH and IGF1 values were also determined in the study group. The mean CH and CRF values were higher in acromegalic patients (12.1±2.2 and 12.3±2.4, respectively) than in healthy subjects (11.0±1.6 and 10.8±1.5, respectively; for CH, p=0.014; for CRF, p=0.001). Mean IOPG measurement was higher in the acromegaly group than in the control group (p=0.017). There was no statistically significant difference in measured CCT (p=0.117) and IOPcc (p=0.594) values between acromegalic patients and healthy subjects. These findings indicate that acromegaly has target organ effects on the eye. Consequently, it can change corneal biomechanical properties such as corneal hysteresis and the CRF. Corneal biomechanical properties are known to affect the accuracy of IOP measurements. These findings should be taken into account when measuring IOP values in acromegaly patients, as IOP readings may be overestimated.

  12. Corneal Biomechanics Determination in Healthy Myopic Subjects

    Directory of Open Access Journals (Sweden)

    Kunliang Qiu

    2016-01-01

    Full Text Available Purpose. To determine the corneal biomechanical properties by using the Ocular Response Analyzer™ and to investigate potential factors associated with the corneal biomechanics in healthy myopic subjects. Methods. 135 eyes from 135 healthy myopic subjects were included in this cross-sectional observational study. Cornea hysteresis (CH, corneal resistance factor (CRF, cornea-compensated intraocular pressure (IOPcc, and Goldmann-correlated intraocular pressure (IOPg were determined with the Reichert Ocular Response Analyzer (ORA. Univariate and multivariate regression analyses were performed to investigate factors associated with corneal biomechanics. Results. The mean CH and CRF were 9.82±1.34 mmHg and 9.64±1.57 mmHg, respectively. In univariate regression analysis, CH was significantly correlated with axial length, refraction, central corneal thickness (CCT, and IOPg (r=-0.27, 0.23, 0.45, and 0.21, resp.; all with p≤0.015, but not with corneal curvature or age; CRF was significantly correlated with CCT and IOPg (r=0.52 and 0.70, resp.; all with p<0.001, but not with axial length/refraction, corneal curvature, or age. In multivariate regression analysis, axial length, IOPcc, and CCT were found to be independently associated with CH, while CCT and IOPg were associated with CRF. Conclusions. Both CH and CRF were positively correlated with CCT. Lower CH but not CRF was associated with increasing degree of myopia. Evaluation of corneal biomechanical properties should take CCT and myopic status into consideration.

  13. Corneal hysteresis in mucopolysaccharidosis I and VI.

    Science.gov (United States)

    Fahnehjelm, Kristina Teär; Chen, Enping; Winiarski, Jacek

    2012-08-01

    High intraocular pressure (IOP) and glaucoma are often suspected in patients with mucopolysaccharidosis (MPS). To determine corneal hysteresis (CH) and IOP in children with mucopolysaccharidosis I-Hurler (MPS I-H) and MPS VI. Clinical measurements with ocular response analyzer (ORA). In seven patients, five with MPS I-H treated with stem cell transplantation (SCT), and two with MPS VI, one treated with SCT and the other with enzyme therapy, the IOP was examined with ORA. Ocular response analyzer measurements were made at a median age of 8.7 years in the patients with MPS I-H and at a median age of 9.3 years in the patients with MPS VI. Earlier measurements had raised suspicion of high IOP in one patient. The ORA showed an increased CH and a falsely high IOP values in all 14 eyes. The recalculated IOPs were normal in all 14 eyes. Mild to severe corneal opacities were present in all 14 eyes. Optic disc areas, borders and cupping were clinically normal in the 12 of 14 eyes that were possible to examine. Severe corneal opacities hampered optic disc evaluation in the older patient with MPS VI. Three eyes in two patients had normal thickness of the retinal nerve fibre layer measured with scanning laser polarimetry with corneal compensation (GDx VCC). No patient was diagnosed or treated for glaucoma. The IOPs are often falsely high because of an increased resistance of the cornea and correlate to the extent of corneal clouding. In this small, cross-sectional study, it appears that corneal resistance is directly correlated with corneal clouding, although a longitudinal study that evaluates resistance as the cornea clears with treatment would provide more direct evidence that corneal deposits are directly related to resistance. A correct measured IOP can avoid unnecessary medical or surgical hypotensive treatment. © 2011 The Authors. Acta Ophthalmologica © 2011 Acta Ophthalmologica Scandinavica Foundation.

  14. Corneal topography and soft contact lens fit.

    Science.gov (United States)

    Young, Graeme; Schnider, Cristina; Hunt, Chris; Efron, Suzanne

    2010-05-01

    To determine which ocular topography variables affect soft contact lens fit. Fifty subjects each wore three pairs of soft lenses in random succession (Vistakon Acuvue 2, Vistakon Acuvue Advance, Ciba Vision Night & Day), and various aspects of lens fit were evaluated. The steeper base curves of each type were worn in one eye and the flatter base curves in the other eye. Corneal topography data were collected using a Medmont E300 corneal topographer (Camberwell, Australia). Corneal curvature, shape factor (SF), and corneal height were measured over a 10 mm chord and also over the maximum measurable diameter. These were measured in the horizontal, vertical, steepest, and flattest meridians. With each lens type, the steeper base curve provided the best fit on the greatest proportion of eyes and the significant differences in various aspects of fit were noted between base curves. For each lens type, there was no significant difference in mean K-reading between those eyes best fit with the steeper base curve and those eyes best fit with the flatter base curve. Two of the lenses showed a positive correlation between centration and horizontal corneal height (maximum), whereas one lens showed a negative correlation between centration and horizontal SF (SF = e). Several lenses showed a positive correlation between post-blink movement and horizontal or vertical corneal SF. The measurement of corneal topography using current Placido disc instrumentation allows a better prediction of soft lens fit than by keratometry, but it is not reliable enough to enable accurate selection of the best fitting base curve. Some correlations are evident between corneal measurements; however, trial fitting remains the method of choice for selection of soft lens base curve.

  15. Corneal Collagen Cross-Linking Outcomes: Review

    OpenAIRE

    Jankov II,Mirko R.; Jovanovic,Vesna; Delevic, Sladjana; Coskunseven, Efekan

    2011-01-01

    Keratoconus is a condition characterized by biomechanical instability of the cornea, presenting in a progressive, asymmetric and bilateral way. Corneal collagen cross-linking with riboflavin and UVA (CXL) is a new technique of corneal tissue strengthening that combines the use of riboflavin as a photo sensitizer and UVA irradiation. The studies showed that CXL was effective in halting the progression of keratoconus over a period of up to four years. The published studies also revealed a reduc...

  16. Intraocular pressure, corneal thickness, and corneal hysteresis in Steinert's myotonic dystrophy

    Directory of Open Access Journals (Sweden)

    Carlos Alexandre de A. Garcia Filho

    2011-06-01

    Full Text Available PURPOSE: Low intraocular pressure (IOP measured by Goldmann applanation tonometry (GAT is one of the ocular manifestations of Steinert's myotonic dystrophy. The goal of this study was to evaluate the corneal-compensated IOP as well as corneal properties (central corneal thickness and corneal hysteresis in patients with myotonic dystrophy. METHODS: A total of 12 eyes of 6 patients with Steinert's myotonic dystrophy (dystrophy group and 12 eyes of 6 age-, race-, and gender-matched healthy volunteers (control group were included in the study. GAT, Dynamic Contour Tonometry (DCT-Pascal and Ocular Response Analyzer (ORA were used to assess the IOP. Central corneal thickness was obtained by ultrasound pachymetry, and corneal hysteresis was analyzed using the ORA device. In light of the multiplicity of tests performed, the significance level was set at 0.01 rather than 0.05. RESULTS: The mean (standard deviation [SD] GAT, DCT, and corneal-compensated ORA IOP in the dystrophy group were 5.4 (1.4 mmHg, 9.7 (1.5 mmHg, and 10.1 (2.6 mmHg, respectively. The mean (SD GAT, DCT, and corneal-compensated ORA IOP in the control group was 12.6 (2.9 mmHg, 15.5 (2.7 mmHg, and 15.8 (3.4 mmHg, respectively. There were significant differences in IOP values between dystrophy and control groups obtained by GAT (mean, -7.2 mmHg; 99% confidence interval [CI], -10.5 to -3.9 mmHg; P<0.001, DCT (mean, -5.9 mmHg; 99% CI, -8.9 to -2.8 mmHg; P<0.001, and corneal-compensated ORA measurements (mean, -5.7 mmHg; 99% CI, -10.4 to -1.0 mmHg; P=0.003. The mean (SD central corneal thickness was similar in the dystrophy (542 [31] µm and control (537 [11] µm groups (P=0.65. The mean (SD corneal hysteresis in the dystrophy and control groups were 11.2 (1.5 mmHg and 9.7 (1.2 mmHg, respectively (P=0.04. CONCLUSIONS: Patients with Steinert's myotonic dystrophy showed lower Goldmann and corneal-compensated IOP in comparison with healthy individuals. Since central corneal thickness and

  17. Effects of axial length and corneal curvature on corneal biomechanics in elderly population

    Directory of Open Access Journals (Sweden)

    Sha-Sha Song

    2018-02-01

    Full Text Available AIM:To explore the corneal biomechanical properties of the elderly with different axial length(ALand corneal curvature by corneal visualization Scheimpflug Technology(Corvis ST. METHODS: Cross-sectional study. A total of 161 patients(297 eyesundergoing phacoemulsification were collected in this study. They were divided into 22-24mm, 24-26mm, more than 26mm groups according to axial length(190 eyes, 54 eyes and 53 eyes, respectively. Those of whom axial length was 22-24mm and the corneal curvature was 42-44D were divided into male and female groups(44 eyes and 49 eyes, respectively. Those of whom axial length was 22-24mm were divided into 42-44D group, more than 44D group according to corneal curvature(88 eyes, 102 eyes, respectively. Corvis ST was used to measure the biomechanical parameters of the cornea. The differences in the parameters between different groups were analyzed using the independent-samples t test or one-way analysis of variance and correlation analyses were performed using Pearson correlation analysis. RESULTS: When comparing the corneal biomechanical parameters, no statistically significant differences were found between male and female groups(P>0.05. The first applanation length and second applanation length among different corneal curvatures were statistically significant(PPr=0.429, 0.278; Pr=-0.291, -0.415; PCONCLUSION: The corneal curvature and ocular axial length may be the factors affecting the corneal biomechanical characteristics. The longer axial length, the thinner corneal thickness, the more easily the corneal is deformed, and with the increase of the axial length, intraocular pressure also increases.

  18. Executive privilege v politickém systému USA

    OpenAIRE

    Janoušková, Johana

    2016-01-01

    This bachelor thesis deals with the privilege of the President of the United States to withhold information from the Congress and ultimately the public, known as the executive privilege. The main theoretical approaches used are the unitary executive theory and also the model of imperial presidency by Arthur M. Schlesinger, which deals with governmental secrecy. The mechanism through which this executive privilege is applied is shown on two case studies. First analysed case is George W. Bush's...

  19. Intracorneal Ring Segments Implantation for Corneal Ectasia.

    Science.gov (United States)

    Giacomin, Natalia T; Mello, Glauco R; Medeiros, Carla S; Kiliç, Alyin; Serpe, Cristine C; Almeida, Hirlana G; Kara-Junior, Newton; Santhiago, Marcony R

    2016-12-01

    To provide an overview of the predictability, safety, and efficacy of intrastromal corneal ring segment (ICRS) implantation as a tool to improve visual acuity and its association with other techniques such as corneal collagen cross-linking (CXL), addressing biomechanical outcomes, models, surgical planning and technique, indications, contraindications, and complications in ectatic corneas. Literature review. ICRSs have been used to regularize the corneal shape and reduce corneal astigmatism and higher order aberrations, improve visual acuity to acceptable limits, and delay, or eventually prevent, a corneal keratoplasty in keratoconic eyes. Changes in ICRS thickness and size, combination of techniques, and the addition of femtosecond lasers to dissect more foreseeable channels represent an improvement toward more predictable results. Several studies have shown, over time, the long-term efficacy and safety of ICRS treatment for keratoconus, with variable predictability, maintaining the early satisfactory outcomes regarding visual acuity, keratometry, and corneal thickness. It is just as important to ensure that the disease will not progress as it is to improve the visual acuity. Therefore, many studies have shown combined techniques using ICRS implantation and CXL. Also, further limitations of ICRS implantation can be addressed when associated with phakic intraocular lens implantation and photorefractive keratectomy. ICRS implantation has shown effectiveness and safety in most cases, including combined procedures. In properly selected eyes, it can improve both refraction and vision in patients with keratoconus. [J Refract Surg. 2016;32(12):829-839.]. Copyright 2016, SLACK Incorporated.

  20. Power, privilege and disadvantage: Intersectionality theory and political representation

    Directory of Open Access Journals (Sweden)

    Eline Severs

    2017-06-01

    Full Text Available This article critically reviews the extant literature on social group representation and clarifies the advantages of intersectionality theory for studying political representation. It argues that the merit of intersectionality theory can be found in its ontology of power. Intersectionality theory is founded on a relational conception of political power that locates the constitution of power relations within social interactions, such as political representation. As such, intersectionality theory pushes scholarship beyond studying representation inequalities —that are linked to presumably stable societal positions— to also consider the ways in which political representation (recreates positions of privilege and disadvantage.

  1. Assessing the influence of registered dietitian order-writing privileges on parenteral nutrition use.

    Science.gov (United States)

    Peterson, Sarah J; Chen, Yimin; Sullivan, Cheryl A; Kinnare, Kelly F; Tupesis, Nicole C; Patel, Gourang P; Sowa, Diane C; Lateef, Omar; Sheean, Patricia M

    2010-11-01

    Previous studies have examined the influence of a nutrition support team on parenteral nutrition (PN) use; however, the influence of registered dietitian (RD) order-writing privileges on appropriate PN use has yet to be reported. A retrospective cohort was conducted at a single tertiary care urban academic medical center to compare adult PN use before RD order-writing privileges (January 1, 2003 to December 31, 2004, pre-privileges) to after RD order-writing privileges (January 1, 2006 to December 31, 2007, post-privileges). RD order-writing privileges were obtained June 2005; PN patients during the washout period (January 1, 2005 to December 31, 2005) were not included. Descriptive statistics were conducted (N=1,965 patients). Although total hospital admissions increased from the pre-privileges to post-privileges periods (Ppoor oral intake (130 to 41 patients), pancreatitis (78 to 26 patients), intractable nausea and vomiting (68 to 23 patients), and mucositis (56 to 18 patients; all Pswriting privileges can decrease inappropriate PN use and costs in a hospital setting. Future studies should continue to highlight the influence of RDs in these advanced practice roles, as well as other members of the nutrition support team, especially with regard to nutrition support delivery and patient outcomes. Copyright © 2010 American Dietetic Association. Published by Elsevier Inc. All rights reserved.

  2. Relationship among Corneal Biomechanics, Anterior Segment Parameters, and Geometric Corneal Parameters

    Directory of Open Access Journals (Sweden)

    Sadık Görkem Çevik

    2016-01-01

    Full Text Available Purpose. To investigate the relationship between corneal biomechanical parameters, anterior segment parameters, and geometric corneal parameters in a healthy Caucasian group. Methods. This retrospective study included the healthy eyes with best corrected visual acuity of at least 20/40 of 122 Caucasian subjects. The anterior segment parameters and geometric corneal parameters such as corneal volume, central corneal thickness, horizontal and vertical corneal radii, anterior and posterior steep, and flat keratometric values were measured with a Scheimpflug camera. The biomechanical properties were measured with Ocular Response Analyzer. Results. One hundred and twenty-two healthy Caucasian subjects (67 males, 55 females with a mean age of 45.32±20.23 were enrolled. Both corneal hysteresis and corneal resistance factor were positively correlated with CCT (r=0.529, p<0.001; r=0.638, p<0.001 and CV (r=0.635, p<0.001; r=0.579, p<0.001 and negatively correlated with age (r=-0.373, p<0.001; r=-0.249, p<0.001. Both in age-gender and multivariate models, CH and CRF had statistically significant negative association with the posterior steep K value. Conclusions. CH and CRF are negatively correlated with posterior steep and average posterior K values.

  3. The scale of substratum topographic features modulates proliferation of corneal epithelial cells and corneal fibroblasts.

    Science.gov (United States)

    Liliensiek, S J; Campbell, S; Nealey, P F; Murphy, C J

    2006-10-01

    The cornea is a complex tissue composed of different cell types, including corneal epithelial cells and keratocytes. Each of these cell types are directly exposed to rich nanoscale topography from the basement membrane or surrounding extracellular matrix. Nanoscale topography has been shown to influence cell behaviors, including orientation, alignment, differentiation, migration, and proliferation. We investigated whether proliferation of SV40-transformed human corneal epithelial cells (SV40-HCECs), primary human corneal epithelial cells (HCECs), and primary corneal fibroblasts is influenced by the scale of topographic features of the substratum. Using basement membrane feature sizes as our guide and the known dimensions of collagen fibrils of the corneal stroma (20-60 nm), we fabricated polyurethane molded substrates, which contain anisotropic feature sizes ranging from 200-2000 nm on pitches ranging from 400 to 4000 nm (pitch = ridge width + groove width). The planar regions separating each of the six patterned regions served as control surfaces. Primary corneal and SV40-HCEC proliferation decreased in direct response to decreasing nanoscale topographies down to 200 nm. In contrast to corneal epithelial cells, corneal fibroblasts did not exhibit significantly different response to any of the topographies when compared with planar controls at 5 days. However, decreased proliferation was observed on the smallest feature sizes after 14 days in culture. Results from these experiments are relevant in understanding the potential mechanisms involved in the control of proliferation and differentiation of cells within the cornea. (c) 2006 Wiley Periodicals, Inc

  4. [The influence of corneal hysteresis and corneal resistance factor on the measurement of intraocular pressure].

    Science.gov (United States)

    Hager, A; Schroeder, B; Sadeghi, M; Grossherr, M; Wiegand, W

    2007-06-01

    The influence of central corneal thickness (CCT) on the measurement of intraocular pressure (IOP) has been discussed extensively in recent years. The problem, however, has not been solved so far. In addition to CCT there are probably further biomechanical properties that play a role in IOP measurement. We wanted to find out whether these properties are related to Goldmann applanation tonometry (GAT), noncontact tonometry (NCT), or CCT. Biomechanical properties of the cornea such as corneal hysteresis (CH) and corneal resistance factor (CRF) can be measured with the Ocular Response Analyzer (ORA, Reichert Ophthalmic Instruments, Depew, NY, USA). Furthermore, a corneal compensated IOP (IOPcc) is given. We examined 156 normal eyes of 80 patients who did not show corneal pathology nor glaucoma. In each eye GAT, NCT, and ORA data as well as CCT were measured. Data were statistically analyzed with respect to agreement and the influence of CH and CRF on IOP measurement. In our patients the following average values were calculated: GAT 14.8+/-3.0 mmHg, NCT 16.4+/-3.9 mmHg, IOPcc 16.2+/-4.1 mmHg, CH 10.6+/-2.3 mmHg, CRF 10.9+/-2.4 mmHg, and CCT 557+/-36 microm. IOPcc was not related to CCT in normal eyes and the only IOP value related to CH (pcorneal thickness. Corneal hysteresis and corneal resistance factor provide further information about biomechanical properties of the cornea beyond central corneal thickness.

  5. Corneal Thickness During Corneal Collagen Cross-Linking with Isotonic Riboflavin Solution without Dextran

    Directory of Open Access Journals (Sweden)

    Refik Oltulu

    2014-08-01

    Full Text Available Objectives: To monitor the corneal thickness change during the dextran-free isotonic riboflavin solution-aided corneal collagen crosslinking procedure in keratoconus patients. Materials and Methods: Corneal thickness measurements during the corneal collagen cross-linking (CXL treatment for progressive keratoconus were evaluated. The corneal thickness measurements were obtained with ultrasonic pachymetry device at five different time points: 0, 15, and 30 minutes after epithelial removal and 15 and 30 minutes after the initiation of UVA irradiation. Results: Twenty-four eyes of 24 patients with progressive keratoconus were included in the study. The thinnest pachymetric values obtained at the 0, 15, and 30 minute measurements after corneal deepithelisation were 409.38±10.43 µm (383-435 µm, 434.56±17.68 µm (400-485 µm, and 457.44±21.78 µm (428-516 µm, respectively. Pachymetric values obtained at 15 and 30 minutes after UVA application to the cornea were 471.69±23.38 µm (439-526 µm and 482.63±23.69 µm (436-524 µm, respectively. The gradual increase was found to be statistically significant when each measurement was compared with the previous values (p<0.001. Conclusion: We found that the corneal thickness was not decreased during the CXL with dextran-free isotonic riboflavin solution; on the contrary, corneal thickness was increased regularly during the procedure. (Turk J Ophthalmol 2014; 44: 272-4

  6. Spatial and temporal variations in extracellular matrix of periocular and corneal regions during corneal stromal development.

    Science.gov (United States)

    Doane, K J; Ting, W H; McLaughlin, J S; Birk, D E

    1996-03-01

    The development of the avian corneal stroma occurs in discrete developmental stages. During this sequence of events, the neural crest-derived corneal fibroblast precursor cells are surrounded by distinct extracellular matrices which change both spatially and temporally. To elucidate the role of these matrices, extracellular matrix components in the periocular mesenchyme and cornea were analysed prior to and during migration and differentiation of corneal fibroblasts using antibodies against collagens, proteoglycans and glycoproteins. Previous work has concentrated on the matrix of the corneal stroma rather than the matrix of the periocular mesenchyme. Since the precursors of the corneal fibroblasts are present within the must migrate through the periocular mesenchyme prior to entry into the cornea proper, this environment was fully evaluated. The present study documents the matrix composition of both the cornea and periocular mesenchyme at developmental stages that are prior to and after initiation of corneal invasion by the corneal fibroblast precursors. Variations in matrix molecules comprising both the periocular mesenchyme and cornea were demonstrated. These include changes in the distribution of collagen types I, II, III, IV and VI; the proteoglycans decorin and lumican; as well as the adhesive glycoproteins tenascin, fibronectin and laminin. It is hypothesized that the variations in matrix localization are important in the regulation of cell migration and differentiation during normal corneal development. Any regulation is likely to involve a combination of components found in the extracellular matrices and therefore, a consideration of the matrix rather than isolated components is required.

  7. Intraocular pressure, corneal thickness, and corneal hysteresis in Steinert's myotonic dystrophy.

    Science.gov (United States)

    Garcia Filho, Carlos Alexandre de A; Prata, Tiago Santos; Sousa, Aline Katia Siqueira; Doi, Larissa Morimoto; Melo Jr, Luiz Alberto Soares

    2011-01-01

    Low intraocular pressure (IOP) measured by Goldmann applanation tonometry (GAT) is one of the ocular manifestations of Steinert's myotonic dystrophy. The goal of this study was to evaluate the corneal-compensated IOP as well as corneal properties (central corneal thickness and corneal hysteresis) in patients with myotonic dystrophy. A total of 12 eyes of 6 patients with Steinert's myotonic dystrophy (dystrophy group) and 12 eyes of 6 age-, race-, and gender-matched healthy volunteers (control group) were included in the study. GAT, Dynamic Contour Tonometry (DCT-Pascal) and Ocular Response Analyzer (ORA) were used to assess the IOP. Central corneal thickness was obtained by ultrasound pachymetry, and corneal hysteresis was analyzed using the ORA device. In light of the multiplicity of tests performed, the significance level was set at 0.01 rather than 0.05. The mean (standard deviation [SD]) GAT, DCT, and corneal-compensated ORA IOP in the dystrophy group were 5.4 (1.4) mmHg, 9.7 (1.5) mmHg, and 10.1 (2.6) mmHg, respectively. The mean (SD) GAT, DCT, and corneal-compensated ORA IOP in the control group was 12.6 (2.9) mmHg, 15.5 (2.7) mmHg, and 15.8 (3.4) mmHg, respectively. There were significant differences in IOP values between dystrophy and control groups obtained by GAT (mean, -7.2 mmHg; 99% confidence interval [CI], -10.5 to -3.9 mmHg; Pcorneal-compensated ORA measurements (mean, -5.7 mmHg; 99% CI, -10.4 to -1.0 mmHg; P=0.003). The mean (SD) central corneal thickness was similar in the dystrophy (542 [31] µm) and control (537 [11] µm) groups (P=0.65). The mean (SD) corneal hysteresis in the dystrophy and control groups were 11.2 (1.5) mmHg and 9.7 (1.2) mmHg, respectively (P=0.04). Patients with Steinert's myotonic dystrophy showed lower Goldmann and corneal-compensated IOP in comparison with healthy individuals. Since central corneal thickness and corneal hysteresis did not differ significantly between groups, the lower IOP readings documented in this

  8. Resistance exercise increases endothelial progenitor cells and angiogenic factors.

    Science.gov (United States)

    Ross, Mark D; Wekesa, Antony L; Phelan, John P; Harrison, Michael

    2014-01-01

    Bone marrow-derived endothelial progenitor cells (EPC) are involved in vascular growth and repair. They increase in the circulation after a single bout of aerobic exercise, potentially related to muscle ischemia. Muscular endurance resistance exercise (MERE) bouts also have the potential to induce muscle ischemia if appropriately structured. The objective of this study is to determine the influence of a single bout of MERE on circulating EPC and related angiogenic factors. Thirteen trained men age 22.4 ± 0.5 yr (mean ± SEM) performed a bout of MERE consisting of three sets of six exercises at participants' 15-repetition maximum without resting between repetitions or exercises. The MERE bout duration was 12.1 ± 0.6 min. Blood lactate and HR were 11.9 ± 0.9 mmol·L and 142 ± 5 bpm, respectively, at the end of MERE. Blood was sampled preexercise and at 10 min, 2 h, and 24 h postexercise. Circulating EPC and serum concentrations of vascular endothelial growth factors (VEGF-A, VEGF-C, and VEGF-D), granulocyte colony stimulating factor, soluble Tie-2, soluble fms-like tyrosine kinase-1, and matrix metalloproteinases (MMP-1, MMP-2, MMP-3, MMP-9, and MMP-9) were higher (P < 0.05) in the postexercise period. Circulating EPC levels were unchanged at 10 min postexercise but higher at 2 h postexercise (P < 0.05). The concentration of most angiogenic factors and metalloproteinases were higher at 10 min postexercise (VEGF-A, +38%; VEGF-C, +40%; VEGF-D, +9%; soluble Tie-2, +15%; soluble fms-like tyrosine kinase-1, +24%; MMP-1, +62%; MMP-2, +3%; MMP-3, +54%; and MMP-9, +45%; all P < 0.05). Soluble E-selectin was lower (P < 0.05) at 2 and 24 h postexercise, with endothelial microparticles and thrombomodulin unchanged. Short intense bouts of MERE can trigger increases in circulating EPC and related angiogenic factors, potentially contributing to vascular adaptation and vasculoprotection.

  9. Interventional pain physicians' experiences of and attitudes toward surgical privileging.

    Science.gov (United States)

    Wright, Thelma B; Enu, Ikay; Stansbury, Lynn G; Roberts, Charles

    2011-01-01

    No consensus guidelines exist on surgical privilege credentialing for nonsurgeons. We queried a group of academic interventional pain physicians about their experiences acquiring such credentials after training, how this process reflected their training, and their current attitudes toward both processes. We designed an interactive, computer-based questionnaire and sent this electronically to the directors of all 93 accredited pain medicine subspecialty fellowship programs in the United States. The questionnaire included 17 items regarding interventional pain medicine training, procedures done, experience of credentialing for surgical privileges, and attitudes toward these processes, with 1 additional space for comments. Of the 93 program directors, 46 (49.5%) responded to our questionnaire. Forty-one (89%) of the respondents were anesthesiologists, and 43 (93%) included some form of implantation procedure in their current practice. Most (83%) of the respondents did fewer than 25 implants per year. Experience doing implant procedures during training varied widely among respondents: 43% did fewer than 5 implant procedures during fellowship; 33.3% did at least 15. Most respondents did their own wound closures and did not feel that immediate surgical backup should be required for interventional pain procedures. Most respondents (78%) felt that pertinent surgical training should be mandatory before credentialing, but fewer than 20% reported having been required to have even a proctoring experience before credentialing. Experience doing implantation procedures during fellowship training and subsequent experience with hospital surgical credentialing seems to vary widely, even among interventional pain physicians associated with academic training programs.

  10. An empirical analysis of White privilege, social position and health

    Science.gov (United States)

    Kwate, Naa Oyo A.; Goodman, Melody S.

    2014-01-01

    Accumulated evidence has demonstrated that social position matters for health. Those with greater socioeconomic resources and greater perceived standing in the social hierarchy have better health than those with fewer resources and perceived standing. Race is another salient axis by which health is stratified in the U.S., but few studies have examined the benefit of White privilege. In this paper, we investigated how perceptions of inequality, subjective and objective social status affected the health and well-being of N=630 White residents in three Boston neighborhoods lying on a social gradient differentiated by race, ethnicity, income and prestige. Outcomes were self-rated health, dental health, and happiness. Results suggested that: neighborhood residence was not associated with health after controlling for individual level factors (e.g., positive ratings of the neighborhood, education level); objective measures of socioeconomic status were associated with better self-reported and dental health, but subjective assessments of social position were more strongly associated; and White residents living in the two wealthiest neighborhoods, and who perceived Black families as welcome in their neighborhoods enjoyed better health than those who believed them to be less welcome. However, those who lived in the least wealthy and most diverse neighborhood fared worse when reporting Black families to be welcome. These results suggest that White privilege and relative social position interact to shape health outcomes. PMID:25014267

  11. Auditing Litigation and Claims: Conflicts and the Compromise of Privilege

    Directory of Open Access Journals (Sweden)

    Harleen Kaur

    2013-12-01

    Full Text Available Auditing standards require an auditor to make various enquiries about liabilities in general this may entail consideration of potential litigations and claims that the audited entity may be facing. To perform this part of audit, the auditors will generally seek representation letters from lawyers of the company detailing an estimate prepared by management, confirmed by their lawyers through a representation letter, and then sent directly to the auditors. This paper reviews the implications for the auditing profession of a case that involved auditors seeking such representation letters. The case involves litigation between theWestpac Banking Corporation and 789TEN Pty Ltd. While theWestpac case confirmed the legal position of the auditor in their task of collecting evidence in order to form an opinion in Australia, it highlights a significant anomaly under the law and should place the issue of solicitor’s representation letters as audit evidence firmly on the agenda of policymakers. This issue of the compromise of legal privilege during the conduct of an audit is also not confined to Australia: other common law jurisdictions, such as the UK and the US, have also sought to clarify the position of auditors when issues of the integrity of legal privacy privilege arise.

  12. The corneal volume and biomechanical corneal factors: Is there any orrelation?

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Sedaghat

    2012-01-01

    Full Text Available Background: The aim of this study was to determine the correlation between corneal hysteresis (CH and the corneal resistance factor (CRF, which are both novel methods of analyzing ocular rigidity/elasticity, and various corneal cha-racteristics, mainly corneal volume in normal subjects. Methods: This cross-sectional study included 500 normal eyes of volunteers. An ocular response analyzer (ORA was used to measure CH and CRF. Patient age and the Pentacam-measured corneal volume (CV, posterior elevation, ante-rior elevation, corneal curvature, central corneal thickness (CCT, corneal thickness of apex (CTA, and corneal thinnest thickness (CTT were compared with CH and CRF. Statistical significance was defined at p < 0.05. Results: The mean CH and CRF for all eyes were 9.9 ± 1.4 mmHg and 10.1 ± 1.6 mmHg, respectively. The mean CVs of the 3, 5, 7, and 10 mm zones for all eyes were 3.8 ± 0.2 mm3, 11.2 ± 0.6 mm3, 24.3 ± 1.4 mm3, and 60.1 ± 3.5 mm3, respectively. The correlations between CV and the hysteresis or CRF were significant in all zones. The CV of the 7-mm zone had the strongest correlation with CH (r = 0.438 and the CV of the 5-mm zone had the strongest correlation with CRF (r = 0.574. Conclusions: CH and CRF correlate with CV. Moreover, the correlation between CV and CRF is stronger than that between CV and CH. The CV may be valuable for determining patient′s qualification for and predicting the outcome of refractive surgery. It would also be helpful in other cases in which corneal biomechanics are important.

  13. Reliability of the Effect of Artificial Anterior Chamber Pressure and Corneal Drying on Corneal Graft Thickness.

    Science.gov (United States)

    Romano, Vito; Steger, Bernhard; Chen, Jern Y; Hassaan, Sherif; Batterbury, Mark; Willoughby, Colin E; Ahmad, Sajjad; Elsheikh, Ahmed; Kaye, Stephen B

    2015-08-01

    To investigate the effect of artificial anterior chamber (AAC) pressure and corneal drying on the graft thickness in preparation for Descemet stripping automated endothelial keratoplasty. Twenty-seven corneoscleral discs were placed in an AAC. The AAC pressure (15, 45, 92, 109, and 198 mm Hg) was controlled using the height of an infusion bottle and a roller clamp. The endothelium was removed in 1 subgroup. Corneas were exposed to room air or repeatedly dried using cellulose spears. Central corneal thickness was measured every 90 seconds for the first 15 minutes and again at 20 minutes using an ultrasound pachymeter (SP-100, Tomey). There was a significant linear relationship between the corneal thickness and both AAC pressure and corneal drying. Very high coefficients of determination and narrow 95% confidence intervals were present, in particular for high pressures and drying. The rate of thinning increased with increasing pressure and drying to 1.6% per minute. At the maximum rate of thinning, a 10% reduction in corneal thickness occurred in 6 minutes or 100 μm in 8.8 minutes. Removal of the corneal endothelium reduced the rate of thinning to 0.3% per minute (R = 0.72). Increasing AAC pressure and corneal drying reduced the graft thickness at a very predictable rate. Adequate corneal thinning can be achieved by increasing the pressure in the AAC by closing the clamp followed by removal of the residual corneal epithelium and repeated drying with a cellulose spear for 5 to 10 minutes, depending on the initial corneal thickness. This method is simple and is both suitable for use in the eye bank and by the surgeon.

  14. Phototherapeutic Keratectomy Outcomes in Superficial Corneal Opacities

    Directory of Open Access Journals (Sweden)

    Khalid Al Arfaj

    2011-01-01

    Full Text Available Purpose Compare the effectiveness of Phototherapeutic keratectomy (PTK in treatment corneal dystrophies versus superficial corneal scars: visual outcomes, recurrence rate and safety profile. Methods PTK was performed in 51 eyes of 51 patients. Data regarding the indications for PTK, ablation depth, symptomatic relief, pre-and postoperative best spectacle-corrected visual acuity (BSCVA, spherical equivalent changes, recurrence and complications were analyzed. The indications for PTK in our study were classified into two categories – group A: patients with corneal dystrophies (n = 23 and the other group B (n = 28 with other indications. Results The average age of the patients was 47 years (±16.4. The mean follow up period was 15.16 months (±10.01 months. Post operatively, there were no significant complications. While the overall BSCVA in the patients improved from 20/41 (0.484 to 20/32 (0.645, group A showed improvement from 20/35 (0.561 to 20/29 (0.687, as compared to group B in which BSCVA improved from 20/47 (0.421 to 20/33 (0.611. The most common indication in group A was granular corneal dystrophy (n = 10 and the most common indication in group B was post traumatic/infectious corneal scar or opacity (n = 10. Eighty-six percent (n = 44 of all patients had alleviation of symptoms. Recurrence of symptoms was seen in 3 eyes of recurrent corneal erosions which required retreatment. Conclusion PTK is a safe and effective procedure. The outcome of this study suggests that PTK improves BSCVA. PTK appears to improve ocular surface health. Furthermore, PTK can be recommended to most patients with corneal dystrophies as a treatment modality prior to other more invasive procedure (viz. penetrating keratoplasty.

  15. Obesity and Cancer: An Angiogenic and Inflammatory Link.

    Science.gov (United States)

    Fukumura, Dai; Incio, Joao; Shankaraiah, Ram C; Jain, Rakesh K

    2016-04-01

    With the current epidemic of obesity, a large number of patients diagnosed with cancer are overweight or obese. Importantly, this excess body weight is associated with tumor progression and poor prognosis. The mechanisms for this worse outcome, however, remain poorly understood. We review here the epidemiological evidence for the association between obesity and cancer, and discuss potential mechanisms focusing on angiogenesis and inflammation. In particular, we will discuss how the dysfunctional angiogenesis and inflammation occurring in adipose tissue in obesity may promote tumor progression, resistance to chemotherapy, and targeted therapies such as anti-angiogenic and immune therapies. Better understanding of how obesity fuels tumor progression and therapy resistance is essential to improve the current standard of care and the clinical outcome of cancer patients. To this end, we will discuss how an anti-diabetic drug such as metformin can overcome these adverse effects of obesity on the progression and treatment resistance of tumors. © 2016 John Wiley & Sons Ltd.

  16. [Anti-angiogenic therapies: from theory to practice].

    Science.gov (United States)

    Bidart, Marie; Berger, François; Pelletier, Laurent

    2013-01-01

    During recent years clear progress has been made in support of tumor pathology. However, the treatment of metastatic disease is now a real therapeutic challenge. Among the new therapeutic strategies, blocking angiogenesis has been the subject of numerous clinical trials. However, if this approach was validated in 2004 by the approval of the first humanized anti-VEGF antibody (bevacizumab or Avastin(®), Roche, 2004), the pre-clinical and clinical studies conducted in the last 5 years have moderated the enthusiasm that these therapies had led in the early 2000s. In November 2011, the US Food and drug administration (FDA) revoke the agency's approval of the breast cancer indication for Avastin(®) because of benefit-risk balance appears negative. This review describes successively the mechanisms of action of antiangiogenic agents, the main anti-angiogenic drugs and the theoretical advantages and practical limitations of these therapies.

  17. Computer-aided Image Processing of Angiogenic Histological.

    Science.gov (United States)

    Sprindzuk, Matvey; Dmitruk, Alexander; Kovalev, Vassili; Bogush, Armen; Tuzikov, Alexander; Liakhovski, Victor; Fridman, Mikhail

    2009-12-01

    This article reviews the questions regarding the image evaluation of angiogeneic histological samples, particularly the ovarian epithelial cancer. Review is focused on the principles of image analysis in the field of histology and pathology. The definition, classification, pathogenesis and angiogenesis regulation in the ovaries are also briefly discussed. It is hoped that the complex image analysis together with the patient's clinical parameters will allow an acquiring of a clear pathogenic picture of the disease, extension of the differential diagnosis and become a useful tool for the evaluation of drug effects. The challenge of the assessment of angiogenesis activity is the heterogeneity of several objects: parameters derived from patient's anamnesis as well as of pathology samples. The other unresolved problems are the subjectivity of the region of interest selection and performance of the whole slide scanning. Angiogenesis; Image processing; Microvessel density; Cancer; Pathology.

  18. Ovarian function following targeted anti-angiogenic therapy with bevacizumab.

    Science.gov (United States)

    Imai, Atsushi; Ichigo, Satoshi; Matsunami, Kazutoshi; Takagi, Hiroshi; Kawabata, Ichiro

    2017-06-01

    Improvements in cancer therapy have enabled further insight into the long-term effects of treatment, including the highly prevalent gonadal failure. The focus of treatment has been shifted to the preservation of fertility, which may be achieved by preventing ovarian toxicity. To this end, new molecular-targeted agents, including monoclonal antibodies, have been developed and used in a standard procedure for managing different cancers. However, the prolonged antitumor activity of these drugs may cause the emergence of new toxic effects. The aim of the present review was to discuss the leading toxic effect of the anti-angiogenic agent bevacizumab on ovarian function in female patients of reproductive age, which may be observed and expected during in clinical practice. The majority of bevacizumab-induced side effects are expected to be transient and eliminated within the anticipated drug clearance time frame; however, fundamental investigations on these effects are required for generating more evidence-based practice guidelines.

  19. Hypoxia-inducible factor as an angiogenic master switch

    Directory of Open Access Journals (Sweden)

    Takuya eHashimoto

    2015-04-01

    Full Text Available Hypoxia-inducible factors (HIFs regulate the transcription of genes that mediate the response to hypoxia. HIFs are constantly expressed and degraded under normoxia, but stabilized under hypoxia. HIFs have been widely studied in physiological and pathological conditions and have been shown to contribute to the pathogenesis of various vascular diseases. In clinical settings, the HIF pathway has been studied for its role in inhibiting carcinogenesis. HIFs might also play a protective role in the pathology of ischemic diseases. Clinical trials of therapeutic angiogenesis after the administration of a single growth factor have yielded unsatisfactory or controversial results, possibly because the coordinated activity of different HIF-induced factors is necessary to induce mature vessel formation. Thus, manipulation of HIF activity to simultaneously induce a spectrum of angiogenic factors offers a superior strategy for therapeutic angiogenesis. Because HIF-2α plays an essential role in vascular remodeling, manipulation of HIF-2α is a promising approach to the treatment of ischemic diseases caused by arterial obstruction, where insufficient development of collateral vessels impedes effective therapy. eIF3e/INT6 interacts specifically with HIF-2α and induces the proteasome inhibitor-sensitive degradation of HIF-2α, independent of hypoxia and VHL. Treatment with eIF3e/INT6 siRNA stabilizes HIF-2α activity even under normoxic conditions and induces the expression of several angiogenic factors, at levels sufficient to produce functional arteries and veins in vivo. We have demonstrated that administration of eIF3e/INT6 siRNA to ischemic limbs or cold-injured brains reduces ischemic damage in animal models. This review summarizes the current understanding of the relationship between HIFs and vascular diseases. We also discuss novel oxygen-independent regulatory proteins that bind HIF-α and the implications of a new method for therapeutic angiogenesis

  20. Development of a rabbit corneal equivalent using an acellular corneal matrix of a porcine substrate.

    Science.gov (United States)

    Xu, Yong-Gen; Xu, Yong-Sheng; Huang, Chen; Feng, Yun; Li, Ying; Wang, Wei

    2008-01-01

    The tissue equivalent that mimics the structure and function of normal tissue is a major bioengineering challenge. Tissue engineered replacement of diseased or damaged tissue has become a reality for some types of tissue such as skin and cartilage. The tissue engineered corneal epithelium, stroma, and endothelium scaffold are promising concepts in overcoming the current limitations of a cornea replacement with an allograft. The acellular corneal matrix from porcine (ACMP) was examined as a potential corneal cell sheet frame. The physical and mechanical properties of strength, expansion, transparency, and water content of the ACMP were measured. The major antigens of the cell components were completely removed with series of extraction methods, the major antigens of the cell components were identified by hematoxylin and eosin (HE), immunofluorescence staining, and scanning electron microscopy. The structural properties were investigated by HE stain and scanning electron microscopy. The three types of rabbit corneal cells were cultured in vitro, and characteristics were investigated by colony formation efficiency (CFE), BrdU staining, immunofluorescence staining, and western blot assay of keratin 3 (K3), vimentin, and aquaporin A. The biocompatibility of the ACMP was investigated for one month using rabbit corneal stroma and three types of cultured corneal cells both in vivo and in vitro. The three types of cultured rabbit corneal cells were seeded onto ACMP of each side at a cell density of 5.0 x 10(3) cells/mm(2). The optical and mechanical properties of the ACMP were similar to the normal porcine cornea. The collagen fiber interconnected to the network, formed regular collagen bundles of the ACMP, and was parallel to the corneal surface. The ACMP was transferred to the rabbit cornea stroma, which showed an intact epithelium and keratocytes in the implant region. There were no inflamed cells or new vessel invasion one month after transplantation. The three types of

  1. Corneal biomechanical properties and intraocular pressure in high myopic anisometropia.

    Science.gov (United States)

    Xu, Suzhong; Xu, Aiqin; Tao, Aizhu; Wang, Jianhua; Fan, Fan; Lu, Fan

    2010-07-01

    To investigate corneal biomechanical properties and intraocular pressure (IOP) in patients with high myopic anisometropia. Patients with high myopic anisometropia (n = 23) and emmetropic subjects (n = 55) were enrolled. Corneal hysteresis (CH), Goldmann-correlated intraocular pressure (IOPg), corneal resistance factor, and corneal-compensated IOP (IOPcc) were measured with Ocular Response Analyzer. Central corneal thickness was measured by optical coherence tomography. Zeiss IOL-Master determined the values of corneal refractive power and ocular axial length. Significant differences were presented in CH, IOPg, and IOPcc among the high myopic, contralateral, and normal eyes (analysis of variance, Panisometropia. High myopic eyes showed decreased CH, but not corneal resistance factor, which indicates that some aspects of corneal biomechanical properties may be altered in high myopic eye of anisometropia. It is also suggested that anisometropic eyes with different refractive errors do not share the same biomechanical properties, which may impact IOP measurement.

  2. Changes on the corneal thickness and curvature after orthokeratology

    Science.gov (United States)

    Mitsui, Iwane; Yamada, Yoshiya

    2004-07-01

    To evaluate the corneal thickness and curvature changes after Orthokeratology contact lens wear, using the ORBSCAN II corneal topography system, corneal thickness and corneal curvature were measured on one hundred and twenty eyes of sixty patients before and after wearing the custom rigid gas permeable contact lenses for Orthokeratology. The contact lenses were specially designed for each eye. The subjects wore the orthokeratology lenses for approximately Four hours with their eyes closed. The corneal thickness of the subjects was increased on fifty-five eyes at not only the peripheral zone but also the center of the cornea. The average increase of central and peripheral corneal thickness was 18 micrometer and 22micrometer, respectively. The mean anterior curvature of corneal surface changed 1.25D. The mean posterior curvature of corneal endothelium side changed 0.75D.

  3. [Use of the confocal laser scanning method for determining corneal topography and corneal tissue effects in refractive corneal surgery].

    Science.gov (United States)

    Koop, N; Brinkmann, R; Schirner, G

    1996-06-01

    Refraction of the cornea head been generally measured with ophthalmometers or computer disk keratometers. We therefore used a confocal laser scanning system for measurement of the corneal topography. Enucleated tonicized pig eyes were measured before and after laser thermokeratoplasty (LTK). The topographical data were used to determine refraction and refractive change; the data were stored digitally. The single images and their differences were displayed on a PC. Unlike conventional ophthalmometry, confocal laser scanning can demonstrate the topographical shape, showing the overall topography of the cornea and local corneal effects, e.g., coagulation, mechanical lesions or high-energy laser effects. Topographical laser scanning has proven to be a generally useful method of determining refraction and surface alterations in corneal refractive surgery.

  4. Corneal reconstruction by stem cells and bioengineering

    Directory of Open Access Journals (Sweden)

    Arjamaa O

    2012-09-01

    Full Text Available Olli ArjamaaDepartment of Biology, University of Turku, Turku, FinlandAbstract: Almost 300 million people are visually impaired worldwide due to various eye diseases such as cataracts, glaucoma, age-related macular degeneration, diabetic retinopathy, and corneal diseases. Notably, ten million people are blind because of severe ocular surface diseases and the majority of cases occur in developing countries. Blinding ocular surface diseases have, however, become treatable by grafting of surface layers, or by full-thickness transplantation of the cornea. As the demand for human corneal tissue for surface reconstruction and transplantation far exceeds the supply, methods are being developed to supplement tissue donation. Xenotransplantation of the cornea or cells from genetically modified pigs may become one of the solutions. Transplantation of limbal stem cells within tissue biopsies, to restore the transparency of the cornea is another remarkable method, which has shown its potential in several clinical studies. The combination of stem cell technology and engineering of biocompatible tissue equivalent, still at preclinical stage, has shown us how synthetic corneal tissue is able to guide cultured corneal stromal stem cells of human origin, to become native-like stroma, the most important layer of the cornea. These findings give hope for a large-quantity production of biomaterial for corneal reconstruction. As such, clinical ophthalmologists should become more familiar with the methods of laboratory science.Keywords: eye, grafting, keratoplasty, xenotransplantation, cell reservoir, biocompatible tissue equivalent

  5. Corneal collagen cross-linking outcomes: review.

    Science.gov (United States)

    Jankov Ii, Mirko R; Jovanovic, Vesna; Delevic, Sladjana; Coskunseven, Efekan

    2011-02-11

    Keratoconus is a condition characterized by biomechanical instability of the cornea, presenting in a progressive, asymmetric and bilateral way. Corneal collagen cross-linking with riboflavin and UVA (CXL) is a new technique of corneal tissue strengthening that combines the use of riboflavin as a photo sensitizer and UVA irradiation. The studies showed that CXL was effective in halting the progression of keratoconus over a period of up to four years. The published studies also revealed a reduction of max K readings by more than 2 D, while the postoperative SEQ was reduced by an average of more than 1 D, and refractive cylinder decreased by about 1 D. No eyes lost any line of BCDVA. Moreover, there was no significant decrease in endothelial cell density. It was also found that CXL treatment was effective with reducing corneal and total wavefront aberrations. Corneal cross-linking has also led to an arrest and/or even a partial reversal of keratectasia in the treatment of iatrogenic ectasia after excimer laser ablation. A primary intervention such as CXL should be considered to potentially increase the biomechanical stability of the corneal tissue and postpone the need of lamellar or penetrating keratoplasty.

  6. Trends in corneal transplantation: indications and techniques.

    Science.gov (United States)

    Ple-Plakon, Patricia A; Shtein, Roni M

    2014-07-01

    To describe trends in corneal transplantation surgery, including indications for surgery, evolution of lamellar keratoplasty, current surgical techniques, and future directions. Over the past decade, anterior and posterior lamellar keratoplasty have begun to supplant penetrating keratoplasty. Surgical techniques continue to change and improve outcomes. In recent years, Descemet membrane endothelial keratoplasty (DMEK) has gained interest as it eliminates the corneal stromal interface, which may limit visual acuity after Descemet stripping automated endothelial keratoplasty. Despite the promising results with improved visual acuity and decreased rejection, the technical challenges associated with DMEK have limited widespread acceptance. With technical refinements and more eye banks providing precut tissue for both Descemet stripping automated endothelial keratoplasty and DMEK, it is likely both procedures will continue to increase over time. Corneal transplantation has evolved rapidly over the past decade, from full-thickness penetrating keratoplasty towards lamellar keratoplasty to only remove and replace damaged layers of the cornea. Achieving minimal induced astigmatism with excellent visual acuity remains a challenge in corneal transplantation. Further refinements in surgical technique may help improve technical challenges and visual outcomes. In this article, we review changing trends in corneal transplantation and highlight developing medical treatments that may be available in the future.

  7. Corneal transplantation: A new view of life.

    Science.gov (United States)

    Amiri, Fardin; Ghiyasvandian, Shahrzad; Navab, Elham; Zakerimoghadam, Masoumeh

    2017-04-01

    The consequences of a corneal transplant are evaluated and classified by care providers, but understanding and interpretation of the results varies between patients, and creates different views for them and influences their lives in different ways while these influences are largely unknown. This study aimed to explore understanding of new life in patients after corneal transplantation. This qualitative study was conducted using a hermeneutic phenomenological approach in Tehran in 2016. Twelve corneal transplant recipients (7 men, 5 women) who were chosen purposefully from penetrating corneal transplant recipients, participated in this study. Semi-structured interviews were used to collect data. The content of the interviews was transcribed and analyzed using Van Manen's methodology. Data analysis led to the emergence of several main themes, among which "having a new sense" and "fear and hope" were two of the most important themes. It can be inferred from the overall participants' experiences that corneal transplant has brought about a new look at life for patients. However, transplant-related issues are endless and continuous, and a sense of fear and hope has always surrounded them.

  8. MicroRNA-184 Regulates Corneal Lymphangiogenesis.

    Science.gov (United States)

    Grimaldo, Sammy; Yuen, Don; Theis, Jaci; Ng, Melissa; Ecoiffier, Tatiana; Chen, Lu

    2015-11-01

    MicroRNAs are a class of small noncoding RNAs that negatively regulate gene expression by binding to complimentary sequences of target messenger RNA. Their roles in corneal lymphangiogenesis are largely unknown. This study was to investigate the specific role of microRNA-184 (mir-184) in corneal lymphangiogenesis (LG) in vivo and lymphatic endothelial cells (LECs) in vitro. Standard murine suture placement model was used to study the expressional change of mir-184 in corneal inflammatory LG and the effect of synthetic mir-184 mimic on this process. Additionally, a human LEC culture system was used to assess the effect of mir-184 overexpression on cell functions in vitro. Expression of mir-184 was significantly downregulated in corneal LG and, accordingly, its synthetic mimic suppressed corneal lymphatic growth in vivo. Furthermore, mir-184 overexpression in LECs inhibited their functions of adhesion, migration, and tube formation in vitro. These novel findings indicate that mir-184 is involved critically in LG and potentially could be used as an inhibitor of the process. Further investigation holds the promise for divulging new therapies for LG disorders, which occur inside and outside the eye.

  9. In-vitro corneal transparency measuring system

    Science.gov (United States)

    Ventura, Liliane; da Costa Vieira, Marcelo A.; Isaac, Flavio; Chiaradia, Caio; Faria de Sousa, Sidney J.

    2001-06-01

    A system for measuring the average corneal transparency of preserved corneas has been developed in order to provide a more accurate and standard report of the corneal tissue. The donated cornea transparency is one of the features to be analyzed previously to its indication for the transplant. The small portable system consists of two main parts: the optical and the electronic parts. The optical system consists of a white light, lenses and pin-holes that collimate white light beams that illuminates the cornea in its preservative medium. The light that passes through the cornea is detected by a resistive detector and the average corneal transparency is shown in a display. In order to obtain just the tissue transparency, the electronic circuit was built in a way that there is a baseline input of the preservative medium, previous to the measurement of the corneal transparency. Manipulating the system consists of three steps: (1) Adjusting the zero percentage in the absence of light (at this time the detectors in the dark); (2) Placing the preservative medium in the system and adjusting the 100% value (this is the baseline input); (3) Preserving the cornea and placing it in the system. The system provides the tissue transparency. The system is connected to an endothelium evaluation system for Slit Lamp, that we have developed, and statistics about the relationship of the corneal transparency and density of the endothelial cells will be provided in the next years. The system is being used in a public Eye Bank in Brasil.

  10. Riboflavin for corneal cross-linking.

    Science.gov (United States)

    O'Brart, D P S

    2016-06-01

    Corneal collagen cross-linking (CXL) with riboflavin and ultraviolet A (UVA) radiation is the first therapeutic modality that appears to arrest the progression of keratoconus and other corneal ectasias. Riboflavin is central to the process, acting as a photosensitizer for the production of oxygen singlets and riboflavin triplets. These free radicals drive the CXL process within the proteins of the corneal stroma, altering its biomechanical properties. Riboflavin also absorbs the majority of the UVA radiation, which is potentially cytotoxic and mutagenic, within the anterior stroma, preventing damage to internal ocular structures, such as the corneal endothelium, lens and retina. Clinical studies report cessation of ectatic progression in over 90% of cases and the majority document significant improvements in visual, keratometric and topographic parameters. Clinical follow-up is limited to 5-10 years, but suggests sustained stability and enhancement in corneal shape. Sight-threatening complications are rare. The optimal stromal riboflavin dosage for CXL is as yet undetermined. Copyright 2016 Prous Science, S.A.U. or its licensors. All rights reserved.

  11. Primary central corneal hemangiosarcoma in a dog.

    Science.gov (United States)

    Haeussler, David J; Rodríguez, Laura Muñoz; Wilkie, David A; Premanandan, Chris

    2011-03-01

    To report a case of primary central corneal hemangiosarcoma in the dog. An 11-year-old, neutered, female, German shepherd mixed breed dog was referred to the Hospital Veterinario Sierra de Madrid (Spain) for evaluation of an enlarging corneal mass of the left eye (OS). The dog was predominantly housed outdoors and was diagnosed with a history of chronic superficial keratitis of both eyes (OU) by the referring veterinarian. The corneal mass was resected by routine superficial keratectomy and submitted for histopathology and Factor VIII immunohistochemical staining. The mass was diagnosed as a corneal hemangiosarcoma with complete excision. Postoperatively, the keratectomy site healed without complication and there was no evidence of recurrence three and a half months postoperatively. Complete systemic evaluation, including abdominal ultrasound and CT scan of the head and thorax, indicated no other detectable neoplasia in the dog. Outdoor housing and ultraviolet exposure, breed, and chronic superficial keratitis were all suspected as contributing factors to the development of a primary corneal hemangiosarcoma. Surgical removal and postoperative treatment for chronic superficial keratitis provided effective therapy. © 2011 American College of Veterinary Ophthalmologists.

  12. "What's Disability Got to Do with It?" Examining Ability Privilege in a Disability Studies Course

    Science.gov (United States)

    Bialka, Christa S.; Morro, Danielle

    2017-01-01

    Although much research addresses prejudice toward and discrimination of individuals with disabilities, few studies engage with the concept of "ability privilege," or the benefits that typically abled individuals are afforded in relation to their position within the hegemony. Given the fledgling nature of research on ability privilege, it…

  13. Orienting Counseling Students toward Multiculturalism: Exploring Privilege during a New Student Orientation

    Science.gov (United States)

    Estrada, Diane; Poulsen, Shruti; Cannon, Edward; Wiggins, Marsha

    2013-01-01

    New counseling students often have strong reactions to the concept of privilege and become anxious when expected to address issues of multiculturalism personally and professionally. In this article, the authors describe a new student orientation model that focuses on addressing privilege and offer steps toward embracing multiculturalism and social…

  14. 17 CFR 240.12f-1 - Applications for permission to reinstate unlisted trading privileges.

    Science.gov (United States)

    2010-04-01

    ... reinstate unlisted trading privileges. 240.12f-1 Section 240.12f-1 Commodity and Securities Exchanges... Rules and Regulations Under the Securities Exchange Act of 1934 Unlisted Trading § 240.12f-1 Applications for permission to reinstate unlisted trading privileges. (a) An application to reinstate unlisted...

  15. 76 FR 19033 - Action Affecting Export Privileges; Credit International Trading Co. Ltd; In the Matter of...

    Science.gov (United States)

    2011-04-06

    ... Bureau of Industry and Security Action Affecting Export Privileges; Credit International Trading Co. Ltd... provided in Section 766.23 of the EAR, I gave notice to Credit International that its export privileges... 766.23 of the Export Administration Regulations (the ``Regulations''), the following entity, Credit...

  16. Talking "Privilege": Barriers to Musical Attainment in Adolescents' Talk of Musical Role Models

    Science.gov (United States)

    Ivaldi, Antonia; O'Neill, Susan

    2009-01-01

    Using a discursive approach, this study explores the ways that adolescents construct the notion of social status and "being privileged" through their talk about musician role models. Drawing on social identity theory (see Tajfel, 1978), we examined how adolescents moved between the relational "in" and "out" groups of being privileged versus being…

  17. Teaching Note--Using Problem-Based Learning to Illustrate the Concepts of Privilege and Oppression

    Science.gov (United States)

    Winfrey Avant, Deneca; Bracy, Wanda

    2015-01-01

    This article presents an overview of problem-based learning and demonstrates how to apply this approach in a course designed to teach students about privilege and oppression. The authors illustrate how to facilitate students' resolution of a complex problem that requires examination of underlying assumptions about how privilege and oppression are…

  18. 36 CFR 1254.50 - Does NARA consider reinstating research privileges?

    Science.gov (United States)

    2010-07-01

    ... reinstatement of research privileges. Mail your appeal to: Archivist of the United States, 8601 Adelphi Road, College Park, MD 20740-6001. (b) The Archivist has 30 calendar days from receipt of an appeal to decide whether to reinstate your research privileges and to respond to you in writing. (c) If the Archivist...

  19. Corneal Biomechanics in Ectatic Diseases: Refractive Surgery Implications

    OpenAIRE

    Ambr?sio, Jr, Renato; Correia, Fernando Faria; Lopes,Bernardo; Salom?o, Marcella Q.; Luz,Allan; Daniel G Dawson; Elsheikh, Ahmed; Vinciguerra, Riccardo; Vinciguerra, Paolo; Roberts, Cynthia J.

    2017-01-01

    Background: Ectasia development occurs due to a chronic corneal biomechanical decompensation or weakness, resulting in stromal thinning and corneal protrusion. This leads to corneal steepening, increase in astigmatism, and irregularity. In corneal refractive surgery, the detection of mild forms of ectasia pre-operatively is essential to avoid post-operative progressive ectasia, which also depends on the impact of the procedure on the cornea. Method: The advent of 3D tomography is proven as a ...

  20. The value of corneal transplantation in reducing blindness.

    Science.gov (United States)

    Garg, P; Krishna, P V; Stratis, A K; Gopinathan, U

    2005-10-01

    To analyse the role of keratoplasty in reducing world blindness due to corneal diseases. Review of published literature. We collected and analysed articles published in the English language literature related to the prevalence and causes of blindness in different parts of the world, causes of corneal blindness, and outcome of corneal transplantation for various corneal diseases. A total of 80% of the world's blind live in developing countries. Retinal diseases are the most important causes of blindness (40-54%) in established economy nations while cataract (44-60%) and corneal diseases (8-25%) are the most common causes of blindness in countries with less developed economies. Keratitis during childhood, trauma, and keratitis during adulthood resulting in a vascularized corneal scar and adherent leucoma are the most frequent causes of corneal blindness in developing countries. Corneal diseases are responsible for 20% of childhood blindness. Nearly 80% of all corneal blindness is avoidable. The outcome of keratoplasty for vascularized corneal scar and adherent leucoma is unsatisfactory, necessitating repeat surgery in a high proportion of these cases. Other barriers for keratoplasty in these nations are suboptimal eye banking, lack of trained human resources, and infrastructure. Since the developing world carries most of the load of corneal blindness and the major causes of corneal blindness are corneal scar and active keratitis, development of corneal transplantation services need a comprehensive approach encompassing medical standards in eye banking, training of cornea specialists and eye banking personnel and exposure of ophthalmologists to care of corneal transplants for better follow-up care. However, concerted efforts should be made to develop and implement prevention strategies since most corneal blindness is preventable.

  1. Corneal hysteresis, corneal resistance factor, and intraocular pressure measurements in eyes implanted with a small aperture corneal inlay.

    Science.gov (United States)

    Agca, Alper; Demirok, Ahmet; Celik, Haci Ugur; van de Pol, Corina; Cankaya, Kadir Ilker; Celik, Nimet Burcu; Yasa, Dilek; Yilmaz, Ihsan; Yilmaz, Omer Faruk

    2014-12-01

    To compare the postoperative corneal hysteresis (CH) and corneal resistance factor (CRF) of eyes implanted with a small aperture corneal inlay versus fellow eyes. Medical records of patients who underwent small aperture corneal inlay (KAMRA; AcuFocus, Inc., Irvine, CA) implantation were retrospectively reviewed. There were two groups: the implanted and non-implanted. Main outcome measures were CH, CRF, Goldmann-correlated intraocular pressure (IOPg), corneal-compensated IOP (IOPcc), and Goldmann applanation tonometry measurements performed preoperatively and at postoperative week 1 and months 1, 3, and 6. The study included 68 eyes of 34 patients. CH was higher in the implanted group when compared with the non-implanted group at postoperative week 1 (12.2 ± 3.1 vs 10.9 ± 1.7 mm Hg; P = .007) and month 1 (12.3 ± 2.5 vs 10.9 ± 1.8 mm Hg; P = .001). CRF was higher in the implanted group when compared with the non-implanted group at postoperative week 1 (11.9 ± 2.9 vs 10.7 ± 1.6 mm Hg; P = .003) and month 1 (12.5 ± 2.5 vs 10.4 ± 1.8 mm Hg; P .05). At the 3-month postoperative visit, all parameters had returned to baseline and there was no change at the 6-month visit. Implantation of the KAMRA corneal inlay does not induce a permanent change in CH or CRF. A transient increase in both was seen in the early postoperative period. Copyright 2014, SLACK Incorporated.

  2. Corneal Stroma Regeneration with Acellular Corneal Stroma Sheets and Keratocytes in a Rabbit Model.

    Science.gov (United States)

    Ma, Xiao Yun; Zhang, Yun; Zhu, Dan; Lu, Yang; Zhou, Guangdong; Liu, Wei; Cao, Yilin; Zhang, Wen Jie

    2015-01-01

    Acellular corneal stroma matrix has been used for corneal stroma engineering. However, because of its compact tissue structure, regrowth of keratocytes into the scaffold is difficult. Previously, we developed a sandwich model for cartilage engineering using acellular cartilage sheets. In the present study, we tested this model for corneal stroma regeneration using acellular porcine corneal stroma (APCS) sheets and keratocytes. Porcine corneas were decellularized by NaCl treatment, and the APCS was cut into 20-μm-thick sheets. A rabbit corneal stroma defect model was created by lamellar keratoplasty and repaired by transplantation of five pieces of APCS sheets with keratocytes. Six months after transplantation, transparent corneas were present in the experimental group, which were confirmed by anterior segment optical coherence tomography examination and transmittance examination. The biomechanical properties in the experimental group were similar to those of normal cornea. Histological analyses showed an even distribution of keratocytes and well-oriented matrix in the stroma layer in the experimental group. Together, these results demonstrated that the sandwich model using acellular corneal stroma sheets and keratocytes could be potentially useful for corneal stroma regeneration.

  3. Value of recombinant human epidermal growth factor in corneal wound repair after corneal foreign body elimination

    Directory of Open Access Journals (Sweden)

    Hong-Jie Han

    2013-11-01

    Full Text Available AIM: To investigate the repair efficacy of recombinant human epidermal growth factor on corneal epithelium after corneal foreign body eliminating operation. METHODS: There were 102 patients with corneal foreign body(188 affected eyeschosen for the study. All patients were divided into treatment group and control group according to the random number table. Both groups received corneal foreign body elimination by slit lamp. Postoperatively, the treatment group was given eye drops containing epidermal growth factor(JinYinShucombined with tobramycin while the control group was only administrated with tobramycin. Treatment effects were compared 3d after treatment. RESULTS: Three days after treatment, the cure rate in the treatment group(93.7%, was significantly higher than that in the control group(76.6%(PPCONCLUSION: The recombinant human epidermal growth factor is capable of integrating with corneal epithelial cells and endothelial cell receptor, shortening healing time of corneal epithelial wound, thus making it an effective treatment of traumatic corneal epithelial defect.

  4. Randomized Trial Comparing Amniotic Membrane Transplantation with Lamellar Corneal Graft for the Treatment of Corneal Thinning.

    Science.gov (United States)

    de Farias, Charles C; Allemann, Norma; Gomes, José Á P

    2016-04-01

    There are few studies comparing different surgical procedures for the treatment of corneal thinning. Lamellar corneal transplantation (LCT) has been reported to be efficient, but its results can be jeopardized by allograft rejection, opacification, or high astigmatism. Amniotic membrane transplantation (AMT) has been considered a good alternative, but it is not as resistant as LCT and the tissue can be reabsorbed after surgery. A prospective, randomized, interventional, and comparative study of consecutive patients with corneal thinning over 6 months was performed. Ophthalmological examination was performed before transplant surgery and then repeated 1, 7, 15, 30, 90, and 180 days after surgery and ultrasound biomicroscopy was performed before and then 30, 90, and 180 days after surgery to assess corneal thinning. Herpes simplex infection was the main cause of corneal thinning (9 eyes), followed by surgery (cataract, glaucoma, 5 cases), rheumatoid arthritis (1), chemical burn (1), perforating trauma (1), previous band keratopathy treatment (1), and Stevens-Johnson syndrome (1). Although all patients showed significant increase in final thickness in the area of thinning, it was higher in those submitted to LCT at 180 days postoperatively. Regardless of the surgical technique, all patients showed epithelialization. Patients undergoing AMT showed an 89% decrease in neovascularization. Final corrected distance visual acuity was better in patients submitted to AMT. LCT proved to be the best option for treating corneal thinning. AMT represents an alternative that allows good visual recovery but does not restore corneal thickness as efficiently as LCT.

  5. [Evaluation of corneal biomechanical properties in glaucoma and control patients by dynamic Scheimpflug corneal imaging technology].

    Science.gov (United States)

    Coste, V; Schweitzer, C; Paya, C; Touboul, D; Korobelnik, J-F

    2015-06-01

    To compare corneal biomechanical properties measured with Corvis Scheimpflug technology (Corvis ST) between a group of patients with chronic open-angle glaucoma and a group of control patients. Prospective observational case-control study. This study enrolled 56 right eyes of 56 patients (G1 [chronic open-angle glaucoma] n=37/G2 [control] n=19). Each patient underwent measurement of corneal biomechanical properties by dynamic Scheimpflug (Corvis ST) camera and the Ocular Response Analyser (ORA), then a measurement of intraocular pressure (IOP) by Goldmann applanation tonometry (GAT) and measurement of central corneal thickness (CCT) by optical coherence tomography during the same visit, by a single clinician. The parameters determined by Corvis ST are: Corvis IOP (IOP Corvis ST), the corneal deformation amplitude (CDA), corneal velocity, the time at highest concavity (TIME CONCAV), the lengths of applanation and their corresponding applanation time. Those studied by ORA are: compensated IOP (IOPcc), non-compensated IOL (IOPg), corneal hysteresis (CH) and corneal resistance factor (CRF). IOP measured on all patients by Corvis ST was positively correlated to GAT (Spearman r=0.569, Pcorneal biomechanical properties between glaucoma and control patients. The cornea of glaucoma patients appears less deformable. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  6. Relationship Between Corneal Hysteresis and Corneal Resistance Factor with Other Ocular Parameters.

    Science.gov (United States)

    Rosa, Nicola; Lanza, Michele; De Bernardo, Maddalena; Signoriello, Giuseppe; Chiodini, Paolo

    2015-01-01

    To evaluate the relationship between corneal hysteresis (CH) and corneal resistance factor (CRF) with age, central corneal thickness (CCT), corneal curvature (KM), corneal volume (CV), and refractive error in naïve eyes. 105 healthy subjects (58 male and 47 female) were included in this study. The ages ranged from 19 to 82 years (mean 43.1 ± 15.4 years) and refraction between -11 D and +6 D (mean -0.79 ± 2.95 D). CH and CRF obtained with the Ocular Response Analyzer (ORA) were correlated with age, refractive error, Goldmann Applanation Tonometry (GAT), and with CCT, KM, CV obtained with the Pentacam, and with Corneal-Compensated Intraocular Pressure (IOPcc) and Goldmann-correlated intraocular pressure measurement (IOPg) obtained with ORA. A multivariable mixed effect model was used to evaluate associations among these parameters. CH ranged from 6.9 to 14.6 mmHg (mean 10.26 ± 1.49 mmHg); CRF ranged from 5.8 to 17 mmHg (mean 10.38 ± 1.64 mmHg). Multivariate analysis showed a statistically significant correlation between CH with CCT (p corneal shape and thickness, and show a decrease of CH with age.

  7. Clinical significance of central corneal thickness and comparison of central corneal thickness

    Directory of Open Access Journals (Sweden)

    Özgür Çakıcı

    2014-03-01

    Full Text Available Significance of central corneal thickness has been increasing in ophthalmology practice. It is an important clinical evaluation tool especially prior to refractive surgery and in diagnosis of glaucoma and keratoconus. Refractive surgery is planned according to preoperative central corneal thickness measurements. Besides, in order to determine actual intraocular pressure, central corneal thickness is measured and corrected eye pressure is obtained. Today, devices used in measurement of central corneal thickness do the measurement according to two principles. First and relatively older method is ultrasonic method. Optic method is the second and more recent method. In daily practice, the most commonly used clinical method in measurement of central corneal thickness is ultrasound pachymeter. However, this measurement technique requires contact between cornea and probe and gives thinner measurement results compared to the methods that use optic principle. Recently, several technologic methods based on optics have been put in use; they provide advantages of non-contact technique and objective determination of central corneal thickness. Of these methods, most commonly used include Specular Microscopy, Optical coherence tomography, Laser Doppler Interferometry, Optical low coherence reflectometry pachymetry, Optic based topographic mapping (also called screening section pachymetry and Pentacam. In this article, it was aimed to evaluate importance of central corneal thickness in clinical use and compare measurement methods. J Clin Exp Invest 2014; 5 (1: 153-158

  8. Analysis of the horizontal corneal diameter, central corneal thickness, and axial length in premature infants

    Directory of Open Access Journals (Sweden)

    Ozdemir Ozdemir

    2014-08-01

    Full Text Available Purpose: To determine the horizontal corneal diameter, central corneal thickness, and axial length in premature infants. Methods: Infants with a birth weight of less than 2,500 g or with a gestation period of less than 36 weeks were included in the study. Infants with retinopathy of prematurity (ROP were allocated to Group 1 (n=138, while those without ROP were allocated to Group 2 (n=236. All infants underwent a complete ophthalmologic examination, including corneal diameter measurements, pachymetry, biometry, and fundoscopy. Between-group comparisons of horizontal corneal diameter, central corneal thickness, and axial lengths were performed. Independent sample t-tests were used for statistical analysis. Results: Data was obtained from 374 eyes of 187 infants (102 female, 85 male. The mean gestational age at birth was 30.7 ± 2.7 weeks (range 25-36 weeks, the mean birth weight was 1,514 ± 533.3 g (range 750-1,970 g, and the mean postmenstrual age at examination was 40.0 ± 4.8 weeks. The mean gestational age and the mean birth weight of Group 1 were statistically lower than Group 2 (p0.05. Conclusions: The presence of ROP in premature infants does not alter the horizontal corneal diameter, central corneal thickness, or axial length.

  9. Corneal Stroma Regeneration with Acellular Corneal Stroma Sheets and Keratocytes in a Rabbit Model.

    Directory of Open Access Journals (Sweden)

    Xiao Yun Ma

    Full Text Available Acellular corneal stroma matrix has been used for corneal stroma engineering. However, because of its compact tissue structure, regrowth of keratocytes into the scaffold is difficult. Previously, we developed a sandwich model for cartilage engineering using acellular cartilage sheets. In the present study, we tested this model for corneal stroma regeneration using acellular porcine corneal stroma (APCS sheets and keratocytes. Porcine corneas were decellularized by NaCl treatment, and the APCS was cut into 20-μm-thick sheets. A rabbit corneal stroma defect model was created by lamellar keratoplasty and repaired by transplantation of five pieces of APCS sheets with keratocytes. Six months after transplantation, transparent corneas were present in the experimental group, which were confirmed by anterior segment optical coherence tomography examination and transmittance examination. The biomechanical properties in the experimental group were similar to those of normal cornea. Histological analyses showed an even distribution of keratocytes and well-oriented matrix in the stroma layer in the experimental group. Together, these results demonstrated that the sandwich model using acellular corneal stroma sheets and keratocytes could be potentially useful for corneal stroma regeneration.

  10. PtmxGuard: An Improved Method for Android Kernel to Prevent Privilege Escalation Attack

    Directory of Open Access Journals (Sweden)

    Kong Bin

    2017-01-01

    Full Text Available Vulnerabilities in Android kernel give opportunity for attacker to damage the system. Privilege escalation is one of the most dangerous attacks, as it helps attacker to gain root privilege by exploiting kernel vulnerabilities. Mitigation technologies, static detection methods and dynamic defense methods have been suggested to prevent privilege escalation attack, but they still have some disadvantages. In this paper, we propose an improved method named PtmxGuard to enhance Android kernel and defeat privilege escalation attack. We focus on a typical attack pattern that attacker hijacks the control flow of Android kernel to modify process credentials by corrupting critical global function pointers. PtmxGuard enforces Code Pointer Integrity to Android kernel, checks the accuracy and reliability of those pointers when they’re triggered by related system calls, and intercepts the system calls when attack activities are detected. Experiment result demonstrates that PtmxGuard can defense privilege escalation attack effectively.

  11. Corneal Diseases in Children in The Gambia | Onabolu | Nigerian ...

    African Journals Online (AJOL)

    trauma in 23 (32.4%) vernal kerato-conjunctivitis in 16 (22.54%), congenital eye diseases in 12 (16.9%), corneal infections in 12 (16.9%), corneal scarring from unknown causes in 5 (7.04%) and corneal dystrophy/degenerations in 3 patients. Ten patients (14%) became bilaterally blind while 22 patients (31%) suffered ...

  12. [Evaluation of corneal endothelium morphology in diabetic patients].

    Science.gov (United States)

    Wesołek-Czernik, Agata; Bartela, Joanna; Zamojska, Ewa; Omulecki, Wojciech

    2007-01-01

    To evaluate the influence of diabetes mellitus and type of hipoglicemic therapy on corneal endothelium cell morphology. In 68 diabetic patients' eyes with non proliferative diabetic retinopathy (29 males and 39 females), corneal endothelium was studied. Patients age was between 50 and 82 years (mean 63.28). As age-matched control group we analyzed 58 eyes of non diabetic patients. Corneal endothelium density, percentage of corneal endothelium hexagonal cells, average size of corneal endothelium cells and corneal thickness were imaged by non-contact specular microscope TOPCON SP-2000P. The mean corneal endothelium cell density was: 2467 cells/mm2 in diabetic patients, and 2573 cells/mm2 in control group. The mean percentage of corneal endothelium hexagonal cells was: 55.3% in diabetic patients treated with insulin and 52.9% in diabetic patients treated with oral antidiabetic drugs, and 54.4% in the control group. The mean size of corneal endothelium cells was: 414.6 microm2 in diabetic patients, and 395.9 microm2 in the control group. The mean corneal thickness was: 0.556 mm in diabetic patients and 0.545 mm in the control group. Corneal endothelium was thicker in diabetic patients than in non diabetic patients. The duration of diabetes mellitus had no influence on corneal endothelium cell morphology. Diabetic patients treated with oral antidiabetic drugs had larger percentage of hexagonal cells than those treated with insulin.

  13. Pattern of corneal opacity in Ibadan, Nigeria | Ashaye | Annals of ...

    African Journals Online (AJOL)

    Background: The prevalence and causes of corneal blindness vary from one region of the world to another. There is even variation within the developing countries of Africa. Method: A retrospective review of 675 patients with corneal scarring out of the 3,753 new patients corneal scarring in patients attending the eye clinic of ...

  14. Mechanical methods in refractive corneal surgery.

    Science.gov (United States)

    Hoffmann, F; Kruse, H; Schüler, A

    1993-08-01

    Keratorefractive surgery has developed rapidly over the past decade. For patients with aphakia, however, posterior chamber lenses are safer and more predictable than refractive corneal surgery; myopia is the greatest challenge to this type of surgery. No technique as yet has an accuracy that is adequate for the general treatment of myopia. Keratotomy is the most common procedure currently performed for the correction of mild myopia and astigmatism. Results are less accurate and less stable with myopic than with aphakic epikeratoplasty. Although it is technically more difficult, keratomileusis seems to be more predictable than epikeratophakia. Nonfreeze lamellar corneal surgery accelerates wound healing. Synthetic lenses and ring-shaped implants are also being developed to modify corneal refraction. Current research is directed toward laser stromal keratomileusis on discs that are removed from the cornea using a microkeratome.

  15. Cataract phacoemulsification and corneal endothelial cell damage

    Directory of Open Access Journals (Sweden)

    Ni Zhu

    2013-07-01

    Full Text Available Phacoemulsification with small incision, reduced number of inflammation cells, and better postoperative recovery has been recognized as the world's most popular option for cataract surgery. Modern cataract surgery is developing gradually from sight rehabilitating to refractive surgery with better vision acuity. Being the most important part of the eye refractive system, maintenance of the cornea's transparency relies heavily upon the healthy endothelial cells. It is well known that there will be endothelial cell loss after phacoemulsification and the damage of the endothelial cells may lead to corneal swellings and opacity, or even the corneal descompensation, which often severely influenced the postoperative vision recovery. This is a review of phacoemulsification and the risk factors of corneal endothelial damage pre-and postoperation.

  16. XENOTRANSPLANTATION – THE FUTURE OF CORNEAL TRANSPLANTATION?

    Science.gov (United States)

    Hara, Hidetaka; Cooper, David K.C.

    2010-01-01

    Although corneal transplantation is readily available in the USA and certain other regions of the developed world, the need for human donor corneas worldwide far exceeds supply. There is currently renewed interest in the possibility of using corneas from other species, especially pigs, for transplantation into humans (xenotransplantation). The biomechanical properties of human and pig corneas are similar. Studies in animal models of corneal xenotransplantation have documented both humoral and cellular immune responses that play roles in xenograft rejection. The results obtained from the Tx of corneas from wild-type (i.e., genetically-unmodified) pigs into nonhuman primates have been surprisingly good and encouraging. Recent progress in the genetic manipulation of pigs has led to the prospect that the remaining immunological barriers will be overcome. There is every reason for optimism that corneal xenoTx will become a clinical reality within the next few years. PMID:21099407

  17. Applications of biomaterials in corneal wound healing.

    Science.gov (United States)

    Tsai, I-Lun; Hsu, Chih-Chien; Hung, Kuo-Hsuan; Chang, Chi-Wen; Cheng, Yung-Hsin

    2015-04-01

    Disease affecting the cornea is a common cause of blindness worldwide. To date, the amniotic membrane (AM) is the most widely used clinical method for cornea regeneration. However, donor-dependent differences in the AM may result in variable clinical outcomes. To overcome this issue, biomaterials are currently under investigation for corneal regeneration in vitro and in vivo. In this article, we highlight the recent advances in hydrogels, bioengineered prosthetic devices, contact lenses, and drug delivery systems for corneal regeneration. In clinical studies, the therapeutic effects of biomaterials, including fibrin and collagen-based hydrogels and silicone contact lenses, have been demonstrated in damaged cornea. The combination of cells and biomaterials may provide potential treatment in corneal wound healing in the future. Copyright © 2014. Published by Elsevier Taiwan.

  18. Applications of biomaterials in corneal wound healing

    Directory of Open Access Journals (Sweden)

    I-Lun Tsai

    2015-04-01

    Full Text Available Disease affecting the cornea is a common cause of blindness worldwide. To date, the amniotic membrane (AM is the most widely used clinical method for cornea regeneration. However, donor-dependent differences in the AM may result in variable clinical outcomes. To overcome this issue, biomaterials are currently under investigation for corneal regeneration in vitro and in vivo. In this article, we highlight the recent advances in hydrogels, bioengineered prosthetic devices, contact lenses, and drug delivery systems for corneal regeneration. In clinical studies, the therapeutic effects of biomaterials, including fibrin and collagen-based hydrogels and silicone contact lenses, have been demonstrated in damaged cornea. The combination of cells and biomaterials may provide potential treatment in corneal wound healing in the future.

  19. Linguistic Privilege and Justice: What can we learn from STEM?

    Energy Technology Data Exchange (ETDEWEB)

    Pronskikh, V. [Fermilab

    2018-01-19

    The linguistic privilege of native speakers in scientific communication, both oral and written, has been widely reported to influence researchers’ publications and careers in and beyond academia. I analyze social structure and communication in the STEM field through the example of big science and attempt to answer the question of why language injustice has a less significant effect on nonnative scientists and engineers than on humanity scholars, scrutinizing the role of signs and nonlinguistic boundary objects in STEM practice and written communication and how they mitigate the emphasis on linguistic eloquence. I suggest that although big science is relatively linguistically inclusive, for collaborative publications and presentations the rhetoric component requirements nevertheless remain at a level comparable to that of the humanities. I draw on the theory of justice to argue that to increase L2 speakers’ and writers’ satisfaction, language standards for international communication must be adjusted to a level convenient for an average L2.

  20. Locating privileged spreaders on an online social network

    Science.gov (United States)

    Borge-Holthoefer, Javier; Rivero, Alejandro; Moreno, Yamir

    2012-06-01

    Social media have provided plentiful evidence of their capacity for information diffusion. Fads and rumors but also social unrest and riots travel fast and affect large fractions of the population participating in online social networks (OSNs). This has spurred much research regarding the mechanisms that underlie social contagion, and also who (if any) can unleash system-wide information dissemination. Access to real data, both regarding topology—the network of friendships—and dynamics—the actual way in which OSNs users interact, is crucial to decipher how the former facilitates the latter's success, understood as efficiency in information spreading. With the quantitative analysis that stems from complex network theory, we discuss who (and why) has privileged spreading capabilities when it comes to information diffusion. This is done considering the evolution of an episode of political protest which took place in Spain, spanning one month in 2011.

  1. The privileges and immunities of international organizations in domestic courts

    CERN Document Server

    2013-01-01

    International organizations are increasingly operating across borders and engaging in legal transactions in virtually all jurisdictions. This makes, familiarity with the applicable law and practice imperative for both international organizations and those who engage in legal relations with them. Furthermore, the issue of whether, how, and to what extent domestic courts take into account decisions of foreign and international courts and tribunals in their own decision-making has become increasingly important in recent years. This book provides a comprehensive empirical study of this transnational judicial dialogue, focusing on the law and practice of domestic jurisdictions concerning the legal personality, privileges, and immunities of international organizations. It presents a selection of detailed country-by-country studies, examining the manner of judicial dialogue across domestic jurisdictions, and between national and international courts. The approach taken in this book intersects with three highly topi...

  2. Pursuing Higher Education: Privileged or Free Access in Romania?

    Directory of Open Access Journals (Sweden)

    Elena-Doina Dascălu

    2016-09-01

    Full Text Available The aim of this paper is to analyze whether higher education in Romania is a privilege or a level of education open to any person willing to pursue it, provided that they have specific abilities and competences. The analysis is carried out from two points of view both legislative and practical (using statistical methods. Based on the results, the paper further explores possible causes for the identified phenomena and formulates adequate policy recommendations. Data on the live births, the numbers of students, teachers and schooling units at each educational level, for the 1948-2011 period have been gathered in order to conduct the research; with regard to statistical methods, pursuing the purpose of this paper, the Engel Granger two steps methodology was employed.

  3. Prescribing Privileges for Psychologists: A Public Service or Hazard?

    Directory of Open Access Journals (Sweden)

    Shaheen E. Lakhan

    2007-07-01

    Full Text Available The privilege to prescribe pharmacotherapeutics has been granted in limited areas to psychologists. The psychologist's role in society may be approaching a great evolution that can dramatically impact the state of mental healthcare and the discipline of psychiatry. Opponents argue drug company funding and cheaper non-PhD psychological professionals fuel the movement for prescription rights for PhD level psychologists. However, proponents claim that this right would equip psychologists with greater psychotherapeutic modalities and the capability of having richer doctor-patient relationships to diagnose and treat underserved populations. Nonetheless, the paucity of prescribing psychologist studies cannot allow the biopsychosocial community to make firm opinions, let alone a decision on this debate. This article reviews the history of clinical psychology and highlights the potential divergence into collaborative clinical and health psychologists and autonomous prescribing psychologists.

  4. Corneal nerve microstructure in Parkinson's disease.

    Science.gov (United States)

    Misra, Stuti L; Kersten, Hannah M; Roxburgh, Richard H; Danesh-Meyer, Helen V; McGhee, Charles N J

    2017-05-01

    Ocular surface changes and blink abnormalities are well-established in Parkinson's disease. Blink rate may be influenced by corneal sub-basal nerve density, however, this relationship has not yet been investigated in Parkinson's disease. This case-control study examined the ocular surface in patients with moderately severe Parkinson's disease, including confocal microscopy of the cornea. Fifteen patients with moderately severe Parkinson's disease (modified Hoehn and Yahr grade 3 or 4) and fifteen control participants were recruited. Ophthalmic assessment included slit-lamp examination, blink rate assessment, central corneal aesthesiometry and in vivo corneal confocal microscopy. The effect of disease laterality was also investigated. Of the 15 patients with Parkinson's disease, ten were male and the mean age was 65.5±8.6years. The corneal sub-basal nerve plexus density was markedly reduced in patients with Parkinson's disease (7.56±2.4mm/mm 2 ) compared with controls (15.91±2.6mm/mm 2 ) (pParkinson's disease (0.79±1.2mBAR) and the control group (0.26±0.35mBAR), p=0.12. Sub-basal nerve density was not significantly different between the eye ipsilateral to the side of the body with most-severe motor symptoms, and the contralateral eye. There was a significant positive correlation between ACE-R scores and sub-basal corneal nerve density (R 2 =0.66, p=0.02). This is the first study to report a significant reduction in corneal sub-basal nerve density in Parkinson's disease and demonstrate an association with cognitive dysfunction. These results provide further evidence to support the involvement of the peripheral nervous system in Parkinson's disease, previously thought to be a central nervous system disorder. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Regulation of Corneal Stroma Extracellular Matrix Assembly

    Science.gov (United States)

    Chen, Shoujun; Mienaltowski, Michael J.; Birk, David E.

    2014-01-01

    The transparent cornea is the major refractive element of the eye. A finely controlled assembly of the stromal extracellular matrix is critical to corneal function, as well as in establishing the appropriate mechanical stability required to maintain corneal shape and curvature. In the stroma, homogeneous, small diameter collagen fibrils, regularly packed with a highly ordered hierarchical organization, are essential for function. This review focuses on corneal stroma assembly and the regulation of collagen fibrillogenesis. Corneal collagen fibrillogenesis involves multiple molecules interacting in sequential steps, as well as interactions between keratocytes and stroma matrix components. The stroma has the highest collagen V:I ratio in the body. Collagen V regulates the nucleation of protofibril assembly, thus controlling the number of fibrils and assembly of smaller diameter fibrils in the stroma. The corneal stroma is also enriched in small leucine-rich proteoglycans (SLRPs) that cooperate in a temporal and spatial manner to regulate linear and lateral collagen fibril growth. In addition, the fibril-associated collagens (FACITs) such as collagen XII and collagen XIV have roles in the regulation of fibril packing and inter-lamellar interactions. A communicating keratocyte network contributes to the overall and long-range regulation of stromal extracellular matrix assembly, by creating micro-domains where the sequential steps in stromal matrix assembly are controlled. Keratocytes control the synthesis of extracellular matrix components, which interact with the keratocytes dynamically to coordinate the regulatory steps into a cohesive process. Mutations or deficiencies in stromal regulatory molecules result in altered interactions and deficiencies in both transparency and refraction, leading to corneal stroma pathobiology such as stromal dystrophies, cornea plana and keratoconus. PMID:25819456

  6. Targeting Metabolic Symbiosis to Overcome Resistance to Anti-angiogenic Therapy

    Directory of Open Access Journals (Sweden)

    Laura Pisarsky

    2016-05-01

    Full Text Available Despite the approval of several anti-angiogenic therapies, clinical results remain unsatisfactory, and transient benefits are followed by rapid tumor recurrence. Here, we demonstrate potent anti-angiogenic efficacy of the multi-kinase inhibitors nintedanib and sunitinib in a mouse model of breast cancer. However, after an initial regression, tumors resume growth in the absence of active tumor angiogenesis. Gene expression profiling of tumor cells reveals metabolic reprogramming toward anaerobic glycolysis. Indeed, combinatorial treatment with a glycolysis inhibitor (3PO efficiently inhibits tumor growth. Moreover, tumors establish metabolic symbiosis, illustrated by the differential expression of MCT1 and MCT4, monocarboxylate transporters active in lactate exchange in glycolytic tumors. Accordingly, genetic ablation of MCT4 expression overcomes adaptive resistance against anti-angiogenic therapy. Hence, targeting metabolic symbiosis may be an attractive avenue to avoid resistance development to anti-angiogenic therapy in patients.

  7. Stromal-Epithelial Interactions and the Angiogenic Phenotype of Breast Cancer

    National Research Council Canada - National Science Library

    Rozenberg, Gabriela I

    2005-01-01

    ... upregulation, and a pro-angiogenic phenotype in culture and in vivo. However, only inhibiting alpha5beta1 activity could phenotypically revert these tumors, reduce invasion and impair angiogenesis in culture...

  8. Clinical outcome, proteome kinetics and angiogenic factors in serum after thermoablation of colorectal liver metastases

    NARCIS (Netherlands)

    Wertenbroek, Marieke W. J. L. A. E.; Schepers, Marianne; Kamminga-Rasker, Hannetta J.; Bottema, Jan T.; Kobold, Anneke C. Muller; Roelofsen, Han; de Jong, Koert P.

    2013-01-01

    Background: Thermoablation is used to treat patients with unresectable colorectal liver metastases (CRLM). We analyze clinical outcome, proteome kinetics and angiogenic markers in patients treated by cryosurgical ablation (CSA) or radiofrequency ablation (RFA). Methods: 205 patients underwent CSA (n

  9. In vitro and in vivo anti-angiogenic activity of girinimbine isolated from Murraya koenigii.

    Science.gov (United States)

    Iman, Venoos; Karimian, Hamed; Mohan, Syam; Hobani, Yahya Hasan; Noordin, Mohamed Ibrahim; Mustafa, Mohd Rais; Noor, Suzita Mohd

    2015-01-01

    Girinimbine is a carbazole alkaloid isolated from the stem bark and root of Murraya koenigii. Here we report that girinimbine is an inhibitor of angiogenic activity both in vitro and in vivo. MTT results showed that girinimbine inhibited proliferation of human umbilical vein endothelial cells, while results from endothelial cell invasion, migration, tube formation, and wound healing assays demonstrated significant time- and dose-dependent inhibition by girinimbine. A proteome profiler array done on girinimbine-treated human umbilical vein endothelial cells showed that girinimbine had mediated regulation of pro-angiogenic and anti-angiogenic proteins. The anti-angiogenic potential of girinimbine was also evidenced in vivo in the zebrafish embryo model wherein girinimbine inhibited neo vessel formation in zebrafish embryos following 24 hours of exposure. Together, these results showed that girinimbine could effectively suppress angiogenesis, suggestive of its therapeutic potential as a novel angiogenesis inhibitor.

  10. Angiogenic endothelium shows lactadherin-dependent phagocytosis of aged erythrocytes and apoptotic cells

    NARCIS (Netherlands)

    Fens, Marcel H. A. M.; Mastrobattista, Enrico; De Graaff, Anko M.; Flesch, Frits M.; Ultee, Anton; Rasmussen, Jan T.; Molema, Grietje; Storm, Gert; Schiffelers, Raymond M.

    2008-01-01

    Angiogenic endothelium plays a crucial role in tumor growth. During angiogenesis, complex alterations in the microenvironment occur. In response, the endothelium undergoes phenotypic changes, for example overexpression of alpha(v)-integrins. Here, we show that the overexpression of

  11. Regulation of angiogenesis in human skeletal muscle with specific focus on pro- angiogenic and angiostatic factors

    DEFF Research Database (Denmark)

    Høier, Birgitte

    It is well established that acute exercise promotes an angiogenic response and that a period of exercise training results in capillary growth. Skeletal muscle angiogenesis is a complex process that requires a coordinated interplay of multiple factors and compounds to ensure proper vascular function...... to exercise in skeletal muscle cells whereas disease is a more determining factor for the capillary network. In conclusion, the findings in the six studies that the PhD thesis is based on provide valuable information to further the understanding of the regulation of human skeletal muscle angiogenesis......, the findings of simultaneously enhanced pro-angiogenic and angiostatic factors in response to acute exercise before training points to that the angiogenic process is highly regulated even when capillary growth is required. The attenuated response in some of the pro-angiogenic factors after training...

  12. Angiogenic factors in chronic lymphocytic leukaemia (CLL): Where do we stand?

    Science.gov (United States)

    Aguirre Palma, Luis Mario; Gehrke, Iris; Kreuzer, Karl-Anton

    2015-03-01

    The role of angiogenesis in haematological malignancies such as chronic lymphocytic leukaemia (CLL) is difficult to envision, because leukaemia cells are not dependent on a network of blood vessels to support basic physiological requirements. Regardless, CLL cells secrete high levels of major angiogenic factors, such as vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), and platelet derived growth factor (PDGF). Nonetheless, it remains unclear how most angiogenic factors regulate accumulation and delayed apoptosis of CLL cells. Angiogenic factors such as leptin, granulocyte colony-stimulating factor (G-CSF), follistatin, angiopoietin-1 (Ang1), angiogenin (ANG), midkine (MK), pleiotrophin (PTN), progranulin (PGRN), proliferin (PLF), placental growth factor (PIGF), and endothelial locus-1 (Del-1), represent novel therapeutic targets of future CLL research but have remained widely overlooked. This review aims to outline our current understanding of angiogenic growth factors and their relationship with CLL, a still uncured haematopoietic malignancy. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  13. Corneal collagen crosslinking for keratoconus. A review

    Directory of Open Access Journals (Sweden)

    M. M. Bikbov

    2014-01-01

    Full Text Available Photochemical crosslinking is widely applied in ophthalmology. Its biochemical effect is due to the release of singlet oxygen that promotes anaerobic photochemical reaction. Keratoconus is one of the most common corneal ectasia affecting 1 in 250 to 250 000 persons. Currently, the rate of iatrogenic ectasia following eximer laser refractive surgery increases due to biomechanical weakening of the cornea. Morphologically and biochemically, ectasia is characterized by corneal layers thinning, contact between the stroma and epithelium resulting from Bowman’s membrane rupture, chromatin fragmentation in keratocyte nuclei, phagocytosis, abnormal staining and arrangement of collagen fibers, enzyme system disorders, and keratocyte apoptosis. In corneal ectasia, altered enzymatic processes result in the synthesis of abnormal collagen. Collagen packing is determined by the activity of various extracellular matrix enzymes which bind amines and aldehydes of collagen fiber amino acids. In the late stage, morphological changes of Descemet’s membrane (i.e., rupture and detachment develop. Abnormal hexagonal-shaped keratocytes and their apoptosis are the signs of endothelial dystrophy. The lack of analogs in domestic ophthalmology encouraged the scientists of Ufa Eye Research Institute to develop a device for corneal collagen crosslinking. The parameters of ultraviolet (i.e., wavelength, exposure time, power to achieve the desired effect were identified. The specifics of some photosensitizers in the course of the procedure were studied. UFalink, a device for UV irradiation of cornea, and photosensitizer Dextralink were developed and adopted. Due to the high risk of endothelial damage, this treatment is contraindicated in severe keratoconus (CCT less than 400 microns. Major effects of corneal collagen crosslinking are the following: Young’s modulus (modulus of elasticity increase by 328.9 % (on average, temperature tolerance increase by 5

  14. Corneal collagen crosslinking for keratoconus. A review

    Directory of Open Access Journals (Sweden)

    M. M. Bikbov

    2014-10-01

    Full Text Available Photochemical crosslinking is widely applied in ophthalmology. Its biochemical effect is due to the release of singlet oxygen that promotes anaerobic photochemical reaction. Keratoconus is one of the most common corneal ectasia affecting 1 in 250 to 250 000 persons. Currently, the rate of iatrogenic ectasia following eximer laser refractive surgery increases due to biomechanical weakening of the cornea. Morphologically and biochemically, ectasia is characterized by corneal layers thinning, contact between the stroma and epithelium resulting from Bowman’s membrane rupture, chromatin fragmentation in keratocyte nuclei, phagocytosis, abnormal staining and arrangement of collagen fibers, enzyme system disorders, and keratocyte apoptosis. In corneal ectasia, altered enzymatic processes result in the synthesis of abnormal collagen. Collagen packing is determined by the activity of various extracellular matrix enzymes which bind amines and aldehydes of collagen fiber amino acids. In the late stage, morphological changes of Descemet’s membrane (i.e., rupture and detachment develop. Abnormal hexagonal-shaped keratocytes and their apoptosis are the signs of endothelial dystrophy. The lack of analogs in domestic ophthalmology encouraged the scientists of Ufa Eye Research Institute to develop a device for corneal collagen crosslinking. The parameters of ultraviolet (i.e., wavelength, exposure time, power to achieve the desired effect were identified. The specifics of some photosensitizers in the course of the procedure were studied. UFalink, a device for UV irradiation of cornea, and photosensitizer Dextralink were developed and adopted. Due to the high risk of endothelial damage, this treatment is contraindicated in severe keratoconus (CCT less than 400 microns. Major effects of corneal collagen crosslinking are the following: Young’s modulus (modulus of elasticity increase by 328.9 % (on average, temperature tolerance increase by 5

  15. Research on inhibition of corneal neovascularization

    Directory of Open Access Journals (Sweden)

    Zhang-Hui Yang

    2015-12-01

    Full Text Available Corneal transparency is the basis of the normal physiological functions.However, corneal neovascularization(CNVmay occur in the infection, mechanical and chemical injury or under other pathological conditions,which make the cornea lose original transparency and severe visual impairment. In recent years, along with the development of immunology, molecular biology, biochemistry and other disciplines, there is more in-depth understanding on the CNV, and clinical treatment of CNV has made new breakthroughs. This article provides an overview of the inhibition of CNV.

  16. Corneal epithelial inclusion cyst in a dog

    Directory of Open Access Journals (Sweden)

    Campos Carla de Freitas

    2002-01-01

    Full Text Available An unilateral corneal epithelial inclusion cyst in a 7-year-old male Boxer dog is reported. The cyst had been observed for thirty days, was unique, not congenital and only one eye was involved. Seven months prior to the referral the dog had manifested indolent corneal ulcer treated with grade keratotomy and third eyelid flap. The cyst was removed by superficial keratectomy followed by a conjunctival pedicle graft. Recovery was uncomplicated and there wasn?t recurrence seven months after the surgery.

  17. The corneal stroma during contact lens wear.

    Science.gov (United States)

    Jalbert, Isabelle; Stapleton, Fiona

    2005-03-01

    Recent technological advances have lead to novel descriptions of the microanatomy of the corneal stroma. In the first section of this review, these findings and the role they play in the maintenance of vital properties such as corneal transparency, mechanical strength, homeostasis, wound-healing response and metabolism are described. In the second part, contact lens induced stromal alterations such as acidosis, oedema, striae, thinning and opacities are reviewed as well as the more recently described phenomenon of microdot deposits and keratocyte loss with an emphasis on how lens wearing stromal effects can be minimised.

  18. The molecular basis of corneal transparency.

    Science.gov (United States)

    Hassell, John R; Birk, David E

    2010-09-01

    The cornea consists primarily of three layers: an outer layer containing an epithelium, a middle stromal layer consisting of a collagen-rich extracellular matrix (ECM) interspersed with keratocytes and an inner layer of endothelial cells. The stroma consists of dense, regularly packed collagen fibrils arranged as orthogonal layers or lamellae. The corneal stroma is unique in having a homogeneous distribution of small diameter 25-30 nm fibrils that are regularly packed within lamellae and this arrangement minimizes light scattering permitting transparency. The ECM of the corneal stroma consists primarily of collagen type I with lesser amounts of collagen type V and four proteoglycans: three with keratan sulfate chains; lumican, keratocan, osteoglycin and one with a chondroitin sulfate chain; decorin. It is the core proteins of these proteoglycans and collagen type V that regulate the growth of collagen fibrils. The overall size of the proteoglycans are small enough to fit in the spaces between the collagen fibrils and regulate their spacing. The stroma is formed during development by neural crest cells that migrate into the space between the corneal epithelium and corneal endothelium and become keratoblasts. The keratoblasts proliferate and synthesize high levels of hyaluronan to form an embryonic corneal stroma ECM. The keratoblasts differentiate into keratocytes which synthesize high levels of collagens and keratan sulfate proteoglycans that replace the hyaluronan/water-rich ECM with the densely packed collagen fibril-type ECM seen in transparent adult corneas. When an incisional wound through the epithelium into stroma occurs the keratocytes become hypercellular myofibroblasts. These can later become wound fibroblasts, which provides continued transparency or become myofibroblasts that produce a disorganized ECM resulting in corneal opacity. The growth factors IGF-I/II are likely responsible for the formation of the well organized ECM associated with transparency

  19. Cells and Angiogenic Cytokines in Therapeutic Angiogenesis for Ischemic Heart Disease

    DEFF Research Database (Denmark)

    Luo, Yu; Zhang, Dai-Fu; Liang, Bo

    2005-01-01

    In the past 20 to 30 years,great developments had been achieved in the applying of cells and angiogenic cytokines for ischemic heart disease.The thesis reviews latest studies of mechanism and clinic application of this novel therapy.......In the past 20 to 30 years,great developments had been achieved in the applying of cells and angiogenic cytokines for ischemic heart disease.The thesis reviews latest studies of mechanism and clinic application of this novel therapy....

  20. Corneal endothelial cytotoxicity of the Calotropis procera (ushaar) plant.

    Science.gov (United States)

    Al-Mezaine, Hani S; Al-Amry, Mohammed A; Al-Assiri, Abdullah; Fadel, Talal S; Tabbara, Khalid F; Al-Rajhi, Ali A

    2008-05-01

    To report 6 eyes of 5 patients with transient corneal edema after exposure to the milky latex of Calotropis procera (ushaar). Interventional case series. Intracorneal penetration of ushaar latex can lead to permanent endothelial cell loss with morphologic alteration. Corneal edema resolved completely in approximately 2 weeks in all cases, despite reduced endothelial cell count and abnormal morphology. Corneal endothelial toxicity of ushaar latex is caused by its ability to penetrate the corneal stroma and induce permanent loss of endothelial cells. Corneal edema resolves if sufficient endothelial cell viability is still present after resolution of ushaar keratitis.

  1. Reversible Corneal Toxicity of Retained Intracameral Perfluoro-n-octane.

    Science.gov (United States)

    Alharbi, Saad S; Asiri, Mohammed S

    2016-01-01

    A 58-year-old female presented with intracameral retained perfluoro-n-octane (PFO) following previous retinal reattachment surgery. After 4 years of follow-up without related sequelae, the patient complained of a gradual decrease in vision secondary to corneal edema with whitish corneal precipitate inferiorly corresponding to the area of retained PFO. Three weeks after anterior chamber washout, corneal edema resolved and the patient obtained 20/40 visual acuity. Even though PFO considered to have a relatively good safety profile, early anterior chamber washout may prevent corneal toxicity and avoid later persistent corneal decompensation.

  2. Current status of accelerated corneal cross-linking

    Directory of Open Access Journals (Sweden)

    Michael Mrochen

    2013-01-01

    Full Text Available Corneal cross-linking with riboflavin is a technique to stabilize or reduce corneal ectasia, in diseases such as keratoconus and post-laser-assisted in situ keratomileusis (LASIK ectasia. There is an interest by patient as well as clinicians to reduce the overall treatment time. Especially, the introduction of corneal cross-linking in combination with corneal laser surgery demands a shorter treatment time to assure a sufficient patient flow. The principles and techniques of accelerated corneal cross-linking is discussed.

  3. [Measurement of viscoelastic corneal parameters (corneal hysteresis) in patients with primary open angle glaucoma].

    Science.gov (United States)

    Schroeder, B; Hager, A; Kutschan, A; Wiegand, W

    2008-10-01

    The ocular response analyzer (ORA) uses an air-pressure-triggered, dynamic, bi-directional corneal applanation method to measure biomechanical parameters of the cornea. Corneal hysteresis (CH) is defined as the difference in intraocular pressure recorded during inward and outward applanation. CH is therefore an indicator for the viscoelastic properties of the cornea. CH was recorded in non-glaucoma patients (80 eyes) as well as in patients with primary open angle glaucoma (POAG, 82 eyes). The correlation between CH and central corneal thickness (CCT) was analyzed. Mean CH was 10.6+/-2.2 mmHg in the non-glaucoma group and 9.3+/-2.2 mmHg in patients with POAG (pcorneal parameters with a significant decrease in corneal hysteresis. A positive correlation between CH and CCT, which was seen in the non-glaucoma group could not be detected in the POAG group.

  4. Quantitative evaluation of corneal epithelial injury caused by n-heptanol using a corneal resistance measuring device in vivo

    Directory of Open Access Journals (Sweden)

    Fukuda M

    2012-04-01

    Full Text Available Masamichi Fukuda1, Hiroshi Sasaki11Department of Ophthalmology, Kanazawa Medical University, Uchinada, JapanPurpose: We attempted to develop a device for measuring electrical corneal resistance (CR using corneal contact lens electrodes to quantitatively evaluate corneal injury in vivo. In the present study, full-thickness detachment of the corneal epithelium was induced by n-heptanol, and the feasibility of the quantitative evaluation of this injury by corneal contact lens electrodes was evaluated in vivo.Methods: The central area of an albino rabbit's cornea was exposed to a filter paper pre-immersed in n-heptanol for 1 minute to induce injury of the corneal epithelium. After induction of injury, the electrical CR was measured and the percentage of CR (%CR was calculated. Fluorescein solution (3 µL was applied to the wound/affected area of the corneal epithelium for photography with a slit-lamp biomicroscope. The wound/affected area was measured using an image analysis system. The correlation between the %CR and the wound/affected area was analyzed.Results: As the size of the wound/affected area of the corneal epithelium increased, the %CR decreased after corneal epithelium detachment. Thus, a close correlation was found between the area of corneal epithelium detachment and the %CR.Conclusion: The corneal resistance device that we developed was capable of quantitatively evaluating n-heptanol-induced full-thickness injuries of the corneal epithelium.Keywords: eyes in vivo, corneal injury, corneal contact lens electrode corneal resistance device, n-heptanol

  5. Normative values for corneal nerve morphology assessed using corneal confocal microscopy: a multinational normative data set.

    Science.gov (United States)

    Tavakoli, Mitra; Ferdousi, Maryam; Petropoulos, Ioannis N; Morris, Julie; Pritchard, Nicola; Zhivov, Andrey; Ziegler, Dan; Pacaud, Danièle; Romanchuk, Kenneth; Perkins, Bruce A; Lovblom, Leif E; Bril, Vera; Singleton, J Robinson; Smith, Gordon; Boulton, Andrew J M; Efron, Nathan; Malik, Rayaz A

    2015-05-01

    Corneal confocal microscopy is a novel diagnostic technique for the detection of nerve damage and repair in a range of peripheral neuropathies, in particular diabetic neuropathy. Normative reference values are required to enable clinical translation and wider use of this technique. We have therefore undertaken a multicenter collaboration to provide worldwide age-adjusted normative values of corneal nerve fiber parameters. A total of 1,965 corneal nerve images from 343 healthy volunteers were pooled from six clinical academic centers. All subjects underwent examination with the Heidelberg Retina Tomograph corneal confocal microscope. Images of the central corneal subbasal nerve plexus were acquired by each center using a standard protocol and analyzed by three trained examiners using manual tracing and semiautomated software (CCMetrics). Age trends were established using simple linear regression, and normative corneal nerve fiber density (CNFD), corneal nerve fiber branch density (CNBD), corneal nerve fiber length (CNFL), and corneal nerve fiber tortuosity (CNFT) reference values were calculated using quantile regression analysis. There was a significant linear age-dependent decrease in CNFD (-0.164 no./mm(2) per year for men, P < 0.01, and -0.161 no./mm(2) per year for women, P < 0.01). There was no change with age in CNBD (0.192 no./mm(2) per year for men, P = 0.26, and -0.050 no./mm(2) per year for women, P = 0.78). CNFL decreased in men (-0.045 mm/mm(2) per year, P = 0.07) and women (-0.060 mm/mm(2) per year, P = 0.02). CNFT increased with age in men (0.044 per year, P < 0.01) and women (0.046 per year, P < 0.01). Height, weight, and BMI did not influence the 5th percentile normative values for any corneal nerve parameter. This study provides robust worldwide normative reference values for corneal nerve parameters to be used in research and clinical practice in the study of diabetic and other peripheral neuropathies. © 2015 by the American Diabetes Association

  6. The Effect of Corneal Epithelium on Corneal Curvature in Patients with Keratoconus.

    Science.gov (United States)

    Akcay, Emine Kalkan; Uysal, Betul Seher; Sarac, Ozge; Ugurlu, Nagehan; Yulek, Fatma; Cagil, Nurullah; Aslan, Nabi

    2015-01-01

    To investigate the effects of corneal epithelium on corneal curvature in patients with keratoconus. This is a prospective, nonrandomized study. Fifty-nine eyes of 47 patients diagnosed as keratoconus and for whom corneal collagen crosslinking (CXL) was recruited in this study. This study is a single-center clinical trial. Pregnancy, lactation, connective tissue disease, corneal thickness below 350 μm, severe dry eyes, or scar of corneal surgery were exclusion criteria. Before and during CXL procedure after removing the corneal epithelium, maximum values of corneal apical curvature, simulated keratometry 1 (Sim-K1), simulated keratometry 2 (Sim-K2), temporal and inferior curvature values, all of which are 1.5 mm from the corneal center, were calculated. These values before and after removal of epithelium were compared statistically. Mean age of patients was 23.30 ± 5.5 (12-38) years. Twenty-eight (59%) were male while 19 (41%) were female. Mean values measured before and after removing the corneal epithelium were: apical curvature; 59.19 ± 7.2 (47.06-82.40) diopter (D) and 61.70 ± 8.8 (49.19-92.66) D (p = 0.001), SimK1; 47.57 ± 4.3 (39.14-64.57) D and 48.23 ± 4.3 (41.89-66.70) D (p = 0.001), SimK2; 52.04 ± 5.3 (43.56-69.34) D and 53.34 ± 5.6 (43.73-70.89) D (p = 0.001), inferior curvature; 53,85 ± 5.2 (43.47-76.56) D and 55.05 ± 5.8 (44.56-81.93) D (p = 0.002), temporal curvature 49.49 ± 5.1 (41.50-71.03) D and 51.53 ± 5.4 (41.58-73.34) D (p = 0.001), respectively. In keratoconus patients during CXL treatment, after removing the corneal epithelium, more steepness is detected in the curvature of the steeper area of the cornea. When evaluating patients with keratoconus, the masking effect of corneal epithelium on values of curvature should be taken into consideration.

  7. The scale of substratum topographic features modulates proliferation of corneal epithelial cells and corneal fibroblasts

    OpenAIRE

    Liliensiek, S.J.; Campbell, S.; Nealey, P. F.; Murphy, C J

    2006-01-01

    The cornea is a complex tissue composed of different cell types, including corneal epithelial cells and keratocytes. Each of these cell types are directly exposed to rich nanoscale topography from the basement membrane or surrounding extracellular matrix. Nanoscale topography has been shown to influence cell behaviors, including orientation, alignment, differentiation, migration, and proliferation. We investigated whether proliferation of SV40-transformed human corneal epithelial cells (SV40-...

  8. Corneal Biomechanical Assessment Using Corneal Visualization Scheimpflug Technology in Keratoconic and Normal Eyes

    OpenAIRE

    Lei Tian; Yi-Fei Huang; Li-Qiang Wang; Hua Bai; Qun Wang; Jing-Jing Jiang; Ying Wu; Min Gao

    2014-01-01

    Purpose. To compare the corneal biomechanical properties of keratoconic patients and age-matched controls using corneal visualization Scheimpflug technology (Corvis ST). Methods. Sixty keratoconic eyes from 47 keratoconus patients and 60 normal eyes from 60 controls were enrolled in this prospective study. Tomography and biomechanical parameters of all eyes were obtained with the Pentacam and Corvis ST, respectively. Intraocular pressure was measured using a Goldmann applanation tonometer. ...

  9. Increased corneal hysteresis after corneal collagen crosslinking: a study based on applanation resonance technology.

    Science.gov (United States)

    Beckman Rehnman, Jeannette; Behndig, Anders; Hallberg, Per; Lindén, Christina

    2014-12-01

    A reliable tool for quantification of the biomechanical status of the cornea in conjunction with corneal collagen crosslinking (CXL) treatment is needed. To quantify the biomechanical effects of CXL in vivo. A prospective, open, case-control study was conducted at the Department of Ophthalmology, Umeå University, Umeå, Sweden. Participants included 28 patients (29 eyes) aged 18 to 28 years with progressive keratoconus and corresponding age- and sex-matched healthy individuals serving as controls. All participants were monitored during a 6-month period between October 13, 2009, and November 5, 2012. Corneal hysteresis after CXL for keratoconus. A difference in corneal hysteresis between the control group and the patients with keratoconus was found at baseline, both with an applanation resonance tonometer (ART) and an ocular response analyzer (ORA), at mean (SD) values of -1.09 (1.92) mm Hg (99% CI, -2.26 to 0.07; P = .01) and -2.67 (2.55) mm Hg (99% CI, -4.05 to -1.32; P corneal hysteresis was demonstrated with an ART 1 and 6 months after CXL, at 1.2 (2.4) mm Hg (99% CI,-0.1 to 2.5; P = .02) and 1.1 (2.7) mm Hg (99% CI, -0.3 to 2.6; P = .04), respectively, but not with ORA. A decrease in corneal thickness was seen 1 and 6 months after treatment (-24 [26] µm, P corneal flattening of -0.6 (0.7) diopters was seen at 6 months (P corneal hysteresis after CXL treatment. Given the large-scale use of CXL in modern keratoconus treatment, a tool with this capacity has a great potential value. Refinement of the ART method of measuring and quantifying corneal biomechanical properties will be a subject of further studies.

  10. Fibrin glue-assisted for the treatment of corneal perforationsusing glycerin-cryopreserved corneal tissue

    Directory of Open Access Journals (Sweden)

    Nuo Dong

    2014-04-01

    Full Text Available AIM: To evaluate the outcomes and safety of lamellar keratoplasty (LK assisted by fibrin glue in corneal perforations.METHODS: Six eyes of 6 patients affected by different corneal pathologies (2 posttraumatic corneal scar and 3 bacterial keratitis underwent LK procedures by using fibrin glue. The mean corneal perforation diameter was 1.35±0.64mm (range, 0.7-2.5mm, and the greatest diameter of the ulcerative stromal defect was 2.47±0.77mm in average (range, 1.5-3.5mm. The donor corneal lamella diameters were 0.20-mm larger and thicker than the recipient to restore a physiologic corneal thickness and shape:mean donor diameter was 8.34±0.28mm (range, 8.2-8.7mm and mean thickness was 352±40.27mm (range, 220-400mm. Mean follow-up was 7.33±1.97 months (range, 6-11 months. Postoperatively, the graft status, graft clarity, anterior chamber response, the visual prognosis, intraocular pressures, and postoperative complications were recorded.RESULTS: All the corneal perforations were successfully healed after the procedure. The best-corrected visual acuity (BCVA ranged from 20/1 000 to 20/50 in their initial presentation, and from 20/100 to 20/20 in their last visit, showed increase in all the patients. No major complications such as graft dislocation and graft failure were noted. Neovascularization developed in the superficial stroma of donor graft in 1 case. High intraocular pressure developed on day 2 after surgery, while was remained in normal range after application of anti-glaucomatous eyedrops for 1 week in 1 case.CONCLUSION: Fibrin glue-assisted sutureless LK is valuable for maintaining the ocular integrity in the treatment of corneal perforations.

  11. Intraoperative corneal thickness change and clinical outcomes after corneal collagen crosslinking: Standard crosslinking versus hypotonic riboflavin.

    Science.gov (United States)

    Rosenblat, Elan; Hersh, Peter S

    2016-04-01

    To determine intraoperative changes in corneal thickness and outcomes of corneal collagen crosslinking (CXL) using 2 intraoperative regimens: riboflavin-dextran or hypotonic riboflavin. Cornea and refractive surgery practice, Teaneck, New Jersey, USA. Prospective randomized case series. Eyes with keratoconus or corneal ectasia were treated. All eyes received preloading with riboflavin 0.1% in 20% dextran. During ultraviolet-A (UVA) exposure, patients were randomly assigned to 1 of 2 study arms; that is, riboflavin-dextran or hypotonic riboflavin. Intraoperative pachymetry was measured before and after the corneal epithelium was removed, after initial riboflavin loading, and after UVA light exposure. Patients were evaluated for maximum keratometry (K), uncorrected distance visual acuity (UDVA), corrected distance visual acuity, corneal thickness, and endothelial cell count (ECC). Forty-eight eyes were treated. After removal of the epithelium and riboflavin loading, the mean pachymetry was 430 μm and 432 μm in the standard group and hypotonic group, respectively. Immediately after 30-minute UVA administration, the mean pachymetry was 302 μm and 342 μm, respectively. There was no statistically significant difference in the postoperative maximum K change, UDVA, corneal thickness, or ECC between the 2 groups. The cornea thinned substantially during the CXL procedure. The use of hypotonic riboflavin rather than riboflavin-dextran during UVA administration decreased the amount of corneal thinning during the procedure by 30%, from 128 μm to 90 μm. However, there were no significant differences in clinical efficacy or changes in ECC or function between groups postoperatively. In general, corneal thinning during CXL did not seem to compromise the safety of the endothelium. Dr. Hersh is a consultant to Avedro, Inc. Dr. Rosenblat has no financial or proprietary interest in any material or method mentioned. Copyright © 2016 ASCRS and ESCRS. Published by Elsevier

  12. Astigmatism induced by intrastromal corneal suture after small incision phacoemulsification.

    Science.gov (United States)

    Chipont-Benabent, E; Artola Roig, A; Pérez-Santonja, J J; Guisbert Medel, M; Alió Sanz, J L

    1998-04-01

    To evaluate the course of astigmatic evolution and complications after clear corneal incisions using an intrastromal corneal suture. Instituto Oftalmologico de Alicante, University of Alicante, Spain. Eighty eyes of 62 patients had endocapsular phacoemulsification. A foldable intraocular lens was implanted through a 4.0 mm clear corneal incision. A 10-0 nylon intrastromal corneal suture was used in all eyes. Change sin corneal astigmatism were calculated by vector analysis; follow-up was 6 months. Early and late suture-related complications were also evaluated. Mean induced cylinder was 1.25 diopters (D) +/- 1.24 (SD) with the wound 1 day postoperatively and 0.19 +/- 0.81 D against the wound at 6 months. There were no incision- or suture-related complications postoperatively. Use of the intrastromal corneal suture led to astigmatically neutral closure of multiplanar corneal incisions.

  13. [Clinical observation of astigmatism induced by corneal incision after phacoemulsification].

    Science.gov (United States)

    Xie, L; Zhu, G; Wang, X

    2001-03-01

    To evaluate the changes of astigmatism induced by corneal incision after phacoemulsification. Phacoemulsification was performed on 62 cases (78 eyes) without suture for a corneal incision. The changes of corneal astigmatism before and after operation in group A (incision at the superior nasal or superior temporal) and B (incision at the steepest corneal meridian) were compared. Three months after the operation, the surgical induced astigmatism was (0.83 plus minus 0.65) D and (0.72 plus minus 0.55) D in group A and B respectively. There was no significant difference, statistically (P > 0.05). The changes of corneal astigmatism were 0.11 D and 0.39 D in group A and B respectively, the difference being statistically significant (P astigmatism is very small after a corneal incision in phacoemulsification without a suture. If the incision is placed on the steepest meridian, the corneal astigmatism can be significantly reduced postoperatively.

  14. Immediately observation on post-LASIK corneal flap

    Directory of Open Access Journals (Sweden)

    Kun Wu

    2014-08-01

    Full Text Available AIM:To immediately observe the complication of corneal flap after LASIK surgery.METHODS:A retrospective case series were studies.Totally 2 040 cases(4 080 eyesfrom January 2010 to October 2012 in our hospital were collected, the corneal flap was observed using lamp microscope after LASIK within 30min. Corneal flap dislocation, corneal flap strial and intraface debris were examined after operation, the effective treatment and controlled measure should be taken for these complications.RESULTS: Postoperative complications were corneal flap dislocation 102 eyes(2.5%, corneal flapstriae 95 eyes(2.33%, interface debris 105 eyes(2.57%. No failure case was seen. There had no corneal flap-related complications, which seriously impact the visual quality after the surgery.CONCLUSION: Carefully postoperative examination at the first-time is an effective way to manage some complications of post-LASIK. Thus promoting the diagnosis and treatment of post-LASIK complications.

  15. Enhancement of Corneal Visibility in Optical Coherence Tomography Images with Corneal Opacification.

    Science.gov (United States)

    Chung, Cheuk Wang; Ang, Marcus; Farook, Mohamed; Strouthidis, Nicholas G; Mehta, Joddhbir S; Mari, Jean Martial; Girard, Michaël J A

    2016-09-01

    To establish and to rank the performance of a corneal adaptive compensation (CAC) algorithm in enhancing corneal images with scars acquired from three commercially available anterior segment optical coherence tomography (ASOCT) devices. Horizontal B-scans of the cornea were acquired from 10 patients using three ASOCT devices (Spectralis, RTVue, and Cirrus). We compared ASOCT image quality (with and without CAC) by computing the intralayer contrast (a measure of shadow removal), the interlayer contrast (a measure of tissue boundary visibility), and the tissue/background contrast (a measure of overall corneal visibility). All six groups (Spectralis, RTVue, Cirrus, Spectralis+CAC, RTVue+CAC, and Cirrus+CAC) were ranked according to a global performance index that averaged all contrast quantities. CAC provided mean intralayer contrasts improvement for all devices (all P images of corneal scars may be enhanced by CAC through shadow removal, improved tissue boundary visibility, and enhanced corneal visibility against the image background. RTVue produces the finest baseline images but the best image quality can be achieved by applying CAC to Spectralis images. CAC could enhance visibility of corneal images with scars acquired from commercially available ASOCT devices and could aid preoperative planning of patients for ophthalmic procedures.

  16. "Tuck In" Lamellar Keratoplasty (TILK) for corneal ectasias involving corneal periphery.

    Science.gov (United States)

    Kaushal, S; Jhanji, V; Sharma, N; Tandon, R; Titiyal, J S; Vajpayee, R B

    2008-02-01

    Evaluation of a new surgical technique for the management of corneal ectasia with peripheral corneal involvement. Twelve eyes of 12 patients with corneal ectasias and peripheral corneal thinning requiring surgical intervention, including eight patients with combined keratoconus and PMD and four patients of keratoglobus, were enrolled for the study in a tertiary care hospital. All patients were contact lens intolerant and had a best corrected visual acuity (BCVA) Keratoplasty (TILK) that included a central lamellar keratoplasty with intrastromal tucking of the peripheral flange was performed in these patients. The main outcome measures analysed were uncorrected visual acuity (UCVA), BCVA, keratometry, refractive status and time for epithelial healing. At the last follow-up (mean: 1.7 years (range 13-48 months)), six patients (50.0%) had BCVA >/=20/60, and all patients had BCVA >/=20/80. The mean keratometry decreased from 57.54 (SD 6.89) D preoperatively to 46.36 (2.39) D (p = 0.003), and the mean spherical equivalent (SEQ) refractive error decreased from -7.8 (4.6) D preoperatively to 1.23 (1.88) D (p = 0.007). A significant decrease was also seen in mean refractive astigmatism which decreased from 5.93 (3.06) D preoperatively to 3.23 (1.14) D (p = 0.037). Our technique of TILK is an effective surgical modality for the management of ectatic corneal dystrophies with peripheral corneal thinning.

  17. [Corneal aberrations before and after corneal and corneoscleral small incision cataract surgery].

    Science.gov (United States)

    Kissner, A; Kohlhaas, M; Spörl, E; Pillunat, L E

    2007-02-01

    The corneal as well as the corneoscleral incisions are considered to be standard in cataract surgery. However, both incision techniques have their advantages and disadvantages. We investigated whether the way of performing the incisions has different effects on the corneal wavefront, especially on higher-order aberrations. Each of 26 patients (6 men, 20 women), aged between 62 and 85 years (average 74.9 +/- 6.69 years), received a standard phakoemulsification by performing a corneal incision on the right eye (group 1) and a corneoscleral incision on the left eye (group 2). The corneal surface was preoperatively investigated by using the corneal wavefront instrument Optikon Keratron Scout, (Schwind Company, Germany). After 6 to 8 weeks the same parameters were measured again. The statistical analysis of the pre- and postoperative data within the same group indicated significant differences (p < 0.05) in group 1 for Z (3 +/- 3) = Trefoil and in group 2 for Z (2 +/- 2) = Astigmatism. On comparing the postoperative data of the corneal incision with those of the corneoscleral incision, there was only a significant difference (p < 0.05) for Z (3 +/- 3) = Trefoil. In accordance with the induced higher-order aberrations both surgical techniques can be considered as being equivalent.

  18. Corneal Backscatters as an Objective Index for Assessing Fuchs’ Endothelial Corneal Dystrophy: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Hsueh-Yen Chu

    2017-01-01

    Full Text Available Purpose. To provide an objective, quantitative approach for monitoring Fuchs’ endothelial corneal dystrophy (FECD, with Scheimpflug imaging. Design. This is a retrospective case-control pilot study. Methods. The study group consisted of 53 eyes in 27 patients diagnosed with FECD, with normal subjects paired as control. Main outcome measures were corneal thickness, morphological patterns on densitograms, and indices of corneal density including the average area density (mean AD and the average ratio of Descemet’s membrane density versus area density (DM/AD in Pentacam Scheimpflug images. Results. There were no significant differences in age and corneal thickness between FECD and normal groups. Morphologically, hanging-hammock patterns were noted on the densitograms of FECD patients, which were different from the high-back chair patterns in normal subjects. Quantitatively, mean AD and DM/AD were both elevated in FECD patients as compared with normal subjects (P=0.01 and 0.025, resp.. In addition, FECD patients with corneal edema had significantly higher mean AD (P=0.018 than those without corneal edema. Conclusions. This pilot study shows that Pentacam system provides an objective, quantitative way to approach FECD corneas. It can assist ophthalmologists in detecting the early change and in monitoring disease progression of FECD. Further studies are needed to consolidate the findings.

  19. Corneal Biomechanical Changes after Crosslinking for Progressive Keratoconus with the Corneal Visualization Scheimpflug Technology

    Directory of Open Access Journals (Sweden)

    Johannes Steinberg

    2014-01-01

    Full Text Available Purpose. To evaluate the effect of corneal crosslinking in progressive keratoconus by applying in vivo corneal visualization Scheimpflug technology. Design. Longitudinal retrospective study. Subjects and Controls. Seventeen eyes of patients treated with corneal crosslinking for progressive keratoconus. Methods. Corneal visualization Scheimpflug technology analyses (research software version 6.07r08 of subjects with progressive keratoconus before and 3 months after corneal crosslinking (CXL were reviewed retrospectively. t-test (for normal distribution and Wilcoxon matched-pairs test (if not normally distributed were used to test for statistically significant differences between pre- and post-CXL analyses. Results. We demonstrated statistically significant differences for the intraocular pressure (median: +3 mmHg, P =0.004, the central corneal pachymetry (pachy; mean: −35 µm, P<0.001, the timespan between the air impulse release and the first applanation of the cornea (A1time; median: +0.12 ms, P<0.05, and the timespan between the air impulse release and the second applanation of the cornea (A2time; median: −37 ms, P<0.05. Conclusions. With the A1time and the A2time, we identified two parameters that demonstrated a statistically significant improvement of the biomechanical properties of the cornea after CXL. Despite the known initial decrease of the pachymetry after CXL, none of the analyzed parameters indicated a progression of the keratoconus.

  20. Elevating pharmacists' scope of practice through a health-system clinical privileging process.

    Science.gov (United States)

    Jordan, Trisha A; Hennenfent, Joel A; Lewin, John J; Nesbit, Todd W; Weber, Robert

    2016-09-15

    The privileging of pharmacists for clinical activities and the impact that privileging has on enhancing the scope of pharmacy practice in health systems are reviewed. Health-system pharmacists or pharmacy leaders must gain a thorough understanding of the credentialing and privileging process as they broaden their scope of practice. Clinical privileging affords an expanded scope of practice that is recognized at the institutional level and formally elevates the pharmacist to that of a nonphysician provider. The installation of privileging processes is expected to take many months to complete for individual institutions and should begin now in anticipation of provider status. Model institutions, including Truman Medical Centers, Johns Hopkins Hospital, and The Ohio State University Wexner Medical Center, are highlighted in this article and provide their individual approach to clinical privileging that can be applied to other institutions. The development and evaluation of these programs have given valuable insight into how this individual approach translates to health systems across the country and how the pharmacy profession can continue to unite to convey the value of pharmacists in improving patient care. In preparation for the potential approval of pharmacist provider status across the United States, it is essential that pharmacists are privileged by the medical staff at their respective institution. Clinical privileges must be strategically developed with a focus on cost and quality aims and meeting the needs of patients. Implementation and maintenance of high-performing pharmacy privileging programs require both successful leadership and management skills and an understanding of the interprofessional nature of healthcare. Copyright © 2016 by the American Society of Health-System Pharmacists, Inc. All rights reserved.

  1. A brief history of corneal transplantation: From ancient to modern

    Directory of Open Access Journals (Sweden)

    Alexandra X Crawford

    2013-01-01

    Full Text Available This review highlights many of the fundamental concepts and events in the development of corneal transplantation - from ancient times to modern. Tales of eye, limb, and even heart transplantation appear in ancient and medieval texts; however, in the scientific sense, the original concepts of corneal surgery date back to the Greek physician Galen (130-200 AD. Although proposals to provide improved corneal clarity by surgical interventions, including keratoprostheses, were better developed by the 17 th and 18 th centuries, true scientific and surgical experimentation in this field did not begin until the 19 th century. Indeed, the success of contemporary corneal transplantation is largely the result of a culmination of pivotal ideas, experimentation, and perseverance by inspired individuals over the last 200 years. Franz Reisinger initiated experimental animal corneal transplantation in 1818, coining the term "keratoplasty". Subsequently, Wilhelmus Thorne created the term corneal transplant and 3 years later Samuel Bigger, 1837, reported successful corneal transplantation in a gazelle. The first recorded therapeutic corneal xenograft on a human was reported shortly thereafter in 1838-unsurprisingly this was unsuccessful. Further progress in corneal transplantation was significantly hindered by limited understanding of antiseptic principles, anesthesiology, surgical technique, and immunology. There ensued an extremely prolonged period of debate and experimentation upon the utility of animal compared to human tissue, and lamellar versus penetrating keratoplasty. Indeed, the first successful human corneal transplant was not performed by Eduard Zirm until 1905. Since that first successful corneal transplant, innumerable ophthalmologists have contributed to the development and refinement of corneal transplantation aided by the development of surgical microscopes, refined suture materials, the development of eye banks, and the introduction of

  2. Effects of hypergravity on the angiogenic potential of endothelial cells.

    Science.gov (United States)

    Costa-Almeida, Raquel; Carvalho, Daniel T O; Ferreira, Miguel J S; Aresta, Guilherme; Gomes, Manuela E; van Loon, Jack J W A; Van der Heiden, Kim; Granja, Pedro L

    2016-11-01

    Angiogenesis, the formation of blood vessels from pre-existing ones, is a key event in pathology, including cancer progression, but also in homeostasis and regeneration. As the phenotype of endothelial cells (ECs) is continuously regulated by local biomechanical forces, studying endothelial behaviour in altered gravity might contribute to new insights towards angiogenesis modulation. This study aimed at characterizing EC behaviour after hypergravity exposure (more than 1g), with special focus on cytoskeleton architecture and capillary-like structure formation. Herein, human umbilical vein ECs (HUVECs) were cultured under two-dimensional and three-dimensional conditions at 3g and 10g for 4 and 16 h inside the large diameter centrifuge at the European Space Research and Technology Centre (ESTEC) of the European Space Agency. Although no significant tendency regarding cytoskeleton organization was observed for cells exposed to high g's, a slight loss of the perinuclear localization of β-tubulin was observed for cells exposed to 3g with less pronounced peripheral bodies of actin when compared with 1g control cells. Additionally, hypergravity exposure decreased the assembly of HUVECs into capillary-like structures, with a 10g level significantly reducing their organization capacity. In conclusion, short-term hypergravity seems to affect EC phenotype and their angiogenic potential in a time and g-level-dependent manner. © 2016 The Author(s).

  3. Cutaneous lesions of secondary syphilis are highly angiogenic.

    Science.gov (United States)

    Macaron, Nada C; Cohen, Cynthia; Chen, Suephy C; Arbiser, Jack L

    2003-06-01

    The role of angiogenesis in infectious processes is poorly studied. Some viruses have been linked to angiogenesis, but the role of bacteria and protozoa in inducing angiogenesis in chronic infections is poorly understood. We examined the role of angiogenesis in syphilis, a common and often difficult-to-treat infectious disease, especially in the setting of HIV/AIDS. Microvessel counts were performed on 27 paraffin-fixed sections of secondary syphilis by staining with monoclonal antibodies against CD31. In addition, immunohistochemistry was performed using antibodies against vascular endothelial growth factor (VEGF) to determine whether increased angiogenesis may be mediated, in part, through increased production of VEGF. The CD31 mean microvessel count in secondary syphilis sections was significantly higher than in normal control sections. VEGF intensity appeared increased in the patients with secondary syphilis. Infection with Treponema pallidum results in increased angiogenesis in secondary syphilis. The mechanism for increased angiogenesis may involve elaboration of angiogenic cytokines, such as VEGF and epidermal growth factor.

  4. Cell viability and angiogenic potential of a bioartificial adipose substitute.

    Science.gov (United States)

    Panneerselvan, Anitha; Nguyen, Luong T H; Su, Yan; Teo, Wee Eong; Liao, Susan; Ramakrishna, Seeram; Chan, Ching Wan

    2015-06-01

    An implantable scaffold pre-seeded with cells needs to remain viable and encourage rapid angiogenesis in order to replace injured tissues, especially for tissue defect repairs. We created a bioartificial adipose graft composed of an electrospun 3D nanofibrous scaffold and fat tissue excised from New Zealand white rabbits. Cell viability and angiogenesis potential of the bioartificial substitute were examined during four weeks of culture in Dulbecco's Modified Eagle Medium by immunohistochemical staining with LIVE/DEAD® cell kit and PECAM-1 antibody, respectively. In addition, a Matrigel® assay was performed to examine the possibility of blood vessels sprouting from the bioartificial graft. Our results showed that cells within the graft were viable and vascular tubes were present at week 4, while cells in a fat tissue block were dead in vitro. In addition, capillaries were observed sprouting from the graft into the Matrigel, demonstrating its angiogenic potential. We expect that improved cell viability and angiogenesis in the bioartificial substitute, compared to intact autologous graft, could potentially contribute to its survival following implantation. Copyright © 2012 John Wiley & Sons, Ltd.

  5. Exogenous and endogenous angiogenic stimuli do not augment splenic autotransplantation.

    Science.gov (United States)

    Power, Richard E; Kay, Elaine W; Bouchier-Hayes, David

    2002-01-01

    To find out if angiogenic stimulation improves the ability of the spleen to regenerate. Experimental study. Teaching hospital, Republic of Ireland. 27 male Sprague-Dawley rats. Each spleen was removed and half was reimplanted in the greater omentum. The rats were randomised into three groups of 9 each: the first (control) group was given no stimulation; the second had the implanted spleen sutured into the omentum with 6/0 polypropylene; and in the third group the implanted spleen was injected with human recombinant vascular endothelial growth factor (VEGF) 500 microg. Clearance of Howell-Jolly bodies, and the weight and histological appearance of the splenic remnant at 3 months. The splenic remnant was significantly larger at 3 months in the control group (p = 0.0006). Histological examination of the tissue from the control group showed that it was architecturally similar to that of normal functioning spleen, whereas the tissue from the two treated groups contained less lymphoid tissue and showed widespread acute and chronic inflammatory changes. There was a significantly greater clearance of Howell-Jolly bodies (an index of splenic function) from the peripheral blood of the control group (p = 0.0009). The excellent recovery of the splenic remnant in the control group suggests that the procedure of splenic autotransplantation might warrant further consideration and study.

  6. Early pregnancy angiogenic proteins levels and pregnancy related hypertensive disorders.

    Science.gov (United States)

    Jakovljevic, Ana; Bogavac, Mirjana; Lozanov-Crvenkovic, Zagorka; Milosević-Tosic, Mirjana; Nikolic, Aleksandra; Mitic, Gorana

    2017-03-01

    Normal placental vascular development depends on multiple interactions of many regulatory molecules including pro and antiangiogenic proteins. It is considered that these vascular modulators might be one of the factors responsible for development hypertensive disorders in pregnancy. To evaluate and compare the early pregnancy (11-14 week of gestation) serum level of angiogenic proteins sFlt1, VEGF i PIGF between different types of pregnancy related hypertensive disorders. The study included 177 pregnant women between 11 and 14 weeks of gestation, divided into four study subgroups (preeclampsia group-41, gestational hypertension group-31, chronic hypertension group-32 and miscarriage group-19) and control group-54. Blood samples (serum) were taken for measuring sFlt1, VEGF i PIGF by a quantitative ELISA technique and measuring other biochemical and hematological parameters. Significantly higher levels of sFlt1 were in the subgroups with preeclampsia and miscarriages, significantly lower level of VEGF in the all study subgroups and lover level of PIGF were in miscarriage group. In the groups with chronic and gestational hypertension there were higher level of sFlt1 and lover level of VEGF than in the control group, but the differences did not reach statistical significance. Early pregnancy imbalance between antiangiogenic protein sFlt1 and proangiogenic molecules VEGF and PIGF could have impact on pathophysiology of placental disorders which leads to development of pregnancy related hypertensive disorders.

  7. Corneal ulcers: For the general practitioner

    African Journals Online (AJOL)

    the skin, e.g. herpes zoster scars, lid lacerations, burns. Lid malposition should be excluded. Facial nerve function must be assessed as dysfunction could affect ... Corneal in ltrate seen as haziness or whitening of the usually transparent cornea is universal to infective ulcers in varying degrees. is signi es the inflammatory ...

  8. Corneal topography measurements for biometric applications

    Science.gov (United States)

    Lewis, Nathan D.

    The term biometrics is used to describe the process of analyzing biological and behavioral traits that are unique to an individual in order to confirm or determine his or her identity. Many biometric modalities are currently being researched and implemented including, fingerprints, hand and facial geometry, iris recognition, vein structure recognition, gait, voice recognition, etc... This project explores the possibility of using corneal topography measurements as a trait for biometric identification. Two new corneal topographers were developed for this study. The first was designed to function as an operator-free device that will allow a user to approach the device and have his or her corneal topography measured. Human subject topography data were collected with this device and compared to measurements made with the commercially available Keratron Piccolo topographer (Optikon, Rome, Italy). A third topographer that departs from the standard Placido disk technology allows for arbitrary pattern illumination through the use of LCD monitors. This topographer was built and tested to be used in future research studies. Topography data was collected from 59 subjects and modeled using Zernike polynomials, which provide for a simple method of compressing topography data and comparing one topographical measurement with a database for biometric identification. The data were analyzed to determine the biometric error rates associated with corneal topography measurements. Reasonably accurate results, between three to eight percent simultaneous false match and false non-match rates, were achieved.

  9. Relationship between Central Corneal Thickness, Vitreous ...

    African Journals Online (AJOL)

    Shufelt C, Fraser-Bell S, Ying-Lai M, Torres M, Varma R. Refractive error, ocular biometry, and lens opalescence in an adult population: The Los Angeles Latino .... J. Age-related changes in central corneal thickness in normal eyes among the adult Lithuanian population. Clinical Interventions in Aging. 2014; 9: 1145-1151.

  10. Corneal Intelligence | Murdoch | Nigerian Journal of Ophthalmology

    African Journals Online (AJOL)

    Nigerian Journal of Ophthalmology. Journal Home · ABOUT · Advanced Search · Current Issue · Archives · Journal Home > Vol 19, No 1 (2011) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register. Corneal Intelligence. I Murdoch. Abstract. No Abstract. Full Text:.

  11. Emergency visits after corneal transplantation in Yemen

    Directory of Open Access Journals (Sweden)

    Mahfouth Abdalla Bamashmus

    2017-01-01

    CONCLUSION: Proper postoperative care is critical for a successful keratoplasty; early intervention of sight-threatening complications increases the chance of graft survival and best-obtained vision. In our corneal transplantation service, all patients are routinely instructed to arrange a same day emergency visit if they experience any symptom in eyes that have undergone keratoplasty.

  12. In vivo characterization of corneal biomechanics.

    Science.gov (United States)

    Piñero, David P; Alcón, Natividad

    2014-06-01

    Interest in corneal biomechanics has increased with the development of new refractive surgery techniques aimed at modifying corneal properties and a variety of surgical options for corneal ectasia management. The human cornea behaves as soft biological material. It is a viscoelastic tissue and its response to a force applied to it depends not only on the magnitude of the force, but also on the velocity of the application. There are concerns about the limitations to measuring corneal biomechanical properties in vivo. To date, 2 systems are available for clinical use: the Ocular Response Analyzer, a dynamic bidirectional applanation device, and the Corvis ST, a dynamic Scheimpflug analyzer device. These devices are useful in clinical practice, especially for planning some surgical procedures and earlier detection of ectatic conditions, but further research is needed to connect the clinical measurements obtained with these devices to the standard mechanical properties. Neither author has a financial or proprietary interest in any material or method mentioned. Copyright © 2014 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  13. Polysaccharide coating of human corneal endothelium

    DEFF Research Database (Denmark)

    Schroder, H D; Sperling, S

    1977-01-01

    Electron microscopy revealed the presence of a 600-1500 A thick layer of polysaccharide on the surface of human corneal endothelial cells. The surface layer was visualized by combined fixation and staining in a mixture of ruthenium red and osmium tetroxide. The coating material was stable...

  14. Serological profile of candidates for corneal donation

    Directory of Open Access Journals (Sweden)

    Adroaldo Lunardelli

    2014-10-01

    Full Text Available Objetive: The purpose of this study is to map the serological profile of candidates to corneal donation at Irmandade Santa Casa de Misericórdia de Porto Alegre, identifying the percentage of disposal by serology and the marker involved. Methods: There have been analised – retrospectively – the results of serology of all corneal donors, made between the period of 1st january 2006 and 31st december 2012. Data analised were related to age, gender and the results of serology pertinent to viral markers (HBsAg, anti-HBc, anti-HCV and anti-HIV, these, determined by immunosorbent tests (ELISA. Results: In the period of the study, there were 2476 corneal donors at the institution, with a major incidence on the male gender, on an average of 58.7 years old. 23% of retention because of serological unfitness was also identified, that is, 570 samples were non-negative to any of the used tests. The marker anti- HBc was the most prevalent on the studied population, followed by the Hepatitis C virus (HCV and by the Human Immunodeficiency Virus (HIV. Conclusion: From the data found through this study, it is essential to have the participation of an efficient service on the serological evaluation of the candidates to corneal donation, once the security of the receptor must be taken into consideration in a population of donors with 23% of unfitness prevalence, in which the most prevalent marker is the one of Hepatits B.

  15. Influence of Pterygium on Corneal Biomechanical Properties.

    Science.gov (United States)

    Öner, Veysi; Taş, Mehmet; Özkaya, Erdal; Bulut, Asker

    2016-07-01

    To evaluate the influence of pterygium on corneal biomechanical properties as measured by the ocular response analyzer (ORA). ORA measurements of 48 eyes with primary nasal pterygium were compared with those of healthy fellow eyes. The mean age of the patients was 46.6 ± 18.9 years. Corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann-correlated intraocular pressure (IOPg), and corneal-compensated IOP (IOPcc) were obtained for each subject by using the ORA (Reichert Ophthalmic Instruments, Depew, NY). CH and CRF were significantly lower in the eyes with pterygium than in the healthy fellow eyes (p1 = 0.011, p2 = 0.014, respectively). On the other hand, there were no significant differences between the eyes with pterygium and healthy fellow eyes concerning IOPg and IOPcc (p1 = 0.948, p2 = 0.129, respectively). The present study showed that biomechanical properties measured by ORA were affected by pterygium. The eyes with primary nasal pterygium had lower CH and CRF than healthy fellow eyes. Therefore, the effect of pterygium should be taken into account in order to make correct diagnoses by ORA.

  16. Change in corneal curvature induced by surgery

    NARCIS (Netherlands)

    G. van Rij (Gabriel)

    1987-01-01

    textabstractThe first section deals with the mechanisms by which sutures, incisions and intracorneal contact lenses produce a change in corneal curvature. To clarify the mechanisms by which incisions and sutures produce astigmatism, we made incisions and placed sutures in the corneoscleral limbus

  17. Morphological evaluation of normal human corneal epithelium

    DEFF Research Database (Denmark)

    Ehlers, Niels; Heegaard, Steffen; Hjortdal, Jesper

    2010-01-01

    eyes were evaluated. The central epithelial, stromal and total corneal thickness was measured as 36.0 µm, 618 µm and 651µm, respectively, with a variation coefficient from 0.21 to 0.22. Pathological appearances were found in 27% of corneas, including thickened basement membrane and alterations...

  18. Past and present of corneal refractive surgery

    DEFF Research Database (Denmark)

    Vestergaard, Anders Højslet

    Surgical correction of refractive errors is becoming increasingly popular. In the 1990s, the excimer laser revolutionized the field of corneal refractive surgery with PRK and LASIK, and lately refractive lenticule extraction (ReLEx) of intracorneal tissue, using only a femtosecond laser, has become...

  19. Corneal Intelligence | Murdoch | Nigerian Journal of Ophthalmology

    African Journals Online (AJOL)

    Nigerian Journal of Ophthalmology. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 19, No 1 (2011) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register. Corneal Intelligence. I Murdoch. Abstract. No Abstract.

  20. Relationship between Central Corneal Thickness, Vitreous ...

    African Journals Online (AJOL)

    The central corneal thickness (CCT), Vitreous chamber depth (VCD) and axial length (AL) are important ocular parameters used in the assessment of ocular health in relation to some ocular morbidities. Determining the differences in these parameters in relation to each other is fundamental to understanding the general eye ...

  1. Inhibition of Corneal Neovascularization by Hydrazinocurcumin

    African Journals Online (AJOL)

    This article previously published in Volume 15 Issue 2 of this journal in February 2016 has been retracted in line with the guidelines from the Committee on Publication Ethics (COPE, http://publicationethics.org/resources/guidelines). Retracted: Zhan W, Zhu J, Zhang Y. Inhibition of corneal neovascularization by ...

  2. Retracted: Inhibition of Corneal Neovascularization by ...

    African Journals Online (AJOL)

    This article previously published in Volume 15 Issue 2 of this journal in February 2016 has been retracted in line with the guidelines from the Committee on Publication Ethics (COPE, http://publicationethics.org/resources/guidelines). Retracted: Zhan W, Zhu J, Zhang Y. Inhibition of corneal neovascularization by ...

  3. The Relationship between Central Corneal Thickness and ...

    African Journals Online (AJOL)

    The aim of this study was to investigate the relationship between central corneal thickness (CCT) and intraocular pressure (IOP) in a predominantly black population. A total of eighty-five subjects (right eyes) with mean age 44.7 ± 15.1 years consisting of 49 males and 36 females were recruited for this study. The central ...

  4. Mathematical analysis of corneal oxygenation | Avtar | International ...

    African Journals Online (AJOL)

    Purpose: To develop a quasi steady state model for the time course concentration profile describing the oxygen diffusion and consumption in a multilayered corneal tissue and investigate the effect of various model parameters on the oxygen concentration for open and closed eyes. Method: A simple mathematical model for ...

  5. Functional evaluation of corneal endothelium by combined measurement of corneal volume alteration and cell density after phacoemulsification.

    Science.gov (United States)

    Suzuki, Hisaharu; Oki, Kotaro; Takahashi, Keizo; Shiwa, Toshihiko; Takahashi, Hiroshi

    2007-12-01

    To assess a new method of functional evaluation of corneal endothelium using combined measurement of corneal volume alteration and cell density (CD) after phacoemulsification. Nippon Medical School Hospital, Tokyo, Japan. Phacoemulsification was performed in 28 cases. The corneal volume within 3.0 mm and 10.0 mm circles of the cornea was measured using Scheimpflug imaging (Pentacam, Oculus, Inc.) and the cell density, using specular microscopy (Noncon Robo, Konan Medical). The volume stress index (VSI), a parameter for measuring functional evaluation, was calculated by dividing the volume increase within the 3.0 mm circle (preoperative corneal volume - corneal volume at time of measurement) by the central cell density value. The resulting value is indicative of the amount of postoperative increase in corneal volume with which each corneal endothelial cell should be able to cope. Three months after surgery, the 3.0 mm corneal volume returned to preoperative values, while the 10.0 mm corneal volume remained significantly higher than preoperatively. The cell density values did not significantly change throughout the study. The VSI showed a significant decrease by 7 days after surgery followed by a gradual decrease until the end of the study. At 3 months, the VSI value was significantly smaller than at 1 day. The corneal volume increase after surgery may be indicative of the degree of the endothelial damage in the area; thus, the VSI may be useful in the functional assessment of the corneal endothelium.

  6. Endothelin-1 enhances corneal fibronectin deposition and promotes corneal epithelial wound healing after photorefractive keratectomy in rabbits.

    Science.gov (United States)

    Lai, Yu-Hung; Wang, Hwei-Zu; Lin, Chang-Ping; Hong, Show-Jen; Chang, Shun-Jen

    2008-05-01

    The objective was to study the effects of endothelin-1 (ET1) on corneal wound healing after photorefractive keratectomy (PRK) in rabbit corneas. Following PRK, 18 New Zealand white rabbits were treated with ET1 in the right eyes and with phosphate-buffered salt solution (PBS) in the left eyes. Corneal epithelial wound size, corneal haze and corneal thickness were recorded. Corneal extracellular matrixes, including collagen types 3, 4 and 7, chondroitin sulfate and fibronectin, were investigated using immunohistochemistry study. ET1 increased the rate of healing of corneal epithelial wounds in rabbits. Anti-fibronectin fluorescence was present at week 12 and week 24 in ET1-treated eyes but not in the control eyes. There were no significant differences in corneal haze, corneal thickness and changes in other extracellular matrixes between ET1- and PBS-treated eyes. ET1 can enhance the deposition of fibronectin in corneal stroma and promote corneal epithelial wound healing after PRK. The increase in fibronectin probably explains the increased healing rate of corneal epithelial wounds.

  7. Endothelin-1 Enhances Corneal Fibronectin Deposition and Promotes Corneal Epithelial Wound Healing after Photorefractive Keratectomy in Rabbits

    Directory of Open Access Journals (Sweden)

    Yu-Hung Lai

    2008-05-01

    Full Text Available The objective was to study the effects of endothelin-1 (ET1 on corneal wound healing after photorefractive keratectomy (PRK in rabbit corneas. Following PRK, 18 New Zealand white rabbits were treated with ET1 in the right eyes and with phosphate-buffered salt solution (PBS in the left eyes. Corneal epithelial wound size, corneal haze and corneal thickness were recorded. Corneal extracellular matrixes, including collagen types 3, 4 and 7, chondroitin sulfate and fibronectin, were investigated using immunohistochemistry study. ET1 increased the rate of healing of corneal epithelial wounds in rabbits. Anti-fibronectin fluorescence was present at week 12 and week 24 in ET1-treated eyes but not in the control eyes. There were no significant differences in corneal haze, corneal thickness and changes in other extracellular matrixes between ET1- and PBS-treated eyes. ET1 can enhance the deposition of fibronectin in corneal stroma and promote corneal epithelial wound healing after PRK. The increase in fibronectin probably explains the increased healing rate of corneal epithelial wounds.

  8. A model for consent-based privilege management in personal electronic health records.

    Science.gov (United States)

    Heinze, Oliver; Bergh, Björn

    2014-01-01

    One of the biggest issues in the domain of standardized, regional, crossinstitutional, personal, electronic health records is the privilege management. While many health information exchange projects use IHE-based architectures there are still unsolved questions regarding the restricting parameters a patient can use in the electronic consent configuring access control. This work determines these parameters, derives an information model of privilege management, introduces a set representation of the model and shows how to apply them to EHR architectures. The introduced model can serve as framework for health information exchanges using a consent-based privilege management. The set representation can help to understand the complexity of consent representations.

  9. Mithramycin exerts an anti-myeloma effect and displays anti-angiogenic effects through up-regulation of anti-angiogenic factors.

    Directory of Open Access Journals (Sweden)

    Eléonore Otjacques

    Full Text Available Mithramycin (MTM, a cytotoxic compound, is currently being investigated for its anti-angiogenic activity that seems to be mediated through an inhibition of the transcription factor SP1. In this study we evaluated its anti-myeloma effects in the syngenic 5TGM1 model in vitro as well as in vivo. In vitro, MTM inhibited DNA synthesis of 5TGM1 cells with an IC50 of 400 nM and induced an arrest in cell cycle progression at the G1/S transition point. Western-blot revealed an up-regulation of p53, p21 and p27 and an inhibition of c-Myc, while SP1 remained unaffected. In rat aortic ring assays, a strong anti-angiogenic effect was seen, which could be explained by a decrease of VEGF production and an up-regulation of anti-angiogenic proteins such as IP10 after MTM treatment. The administration of MTM to mice injected with 5TGM1 decreased 5TGM1 cell invasion into bone marrow and myeloma neovascularisation. These data suggest that MTM displays anti-myeloma and anti-angiogenic effects that are not mediated by an inhibition of SP1 but rather through c-Myc inhibition and p53 activation.

  10. Prolonged hypoxic culture and trypsinization increase the pro-angiogenic potential of human adipose tissue-derived stem cells

    DEFF Research Database (Denmark)

    Rasmussen, Jeppe Grøndahl; Frøbert, Ole; Pilgaard, Linda

    2011-01-01

    Transplantation of mesenchymal stromal cells (MSC), including adipose tissue-derived stem cells (ASC), is a promising option in the treatment of vascular disease. Short-term hypoxic culture of MSC augments secretion of anti-apoptotic and angiogenic cytokines. We hypothesized that prolonged hypoxi...... (1% and 5% oxygen) culture and trypsinization would augment ASC expression of anti-apoptotic and angiogenic cytokines and increase the angiogenic potential of ASC-conditioned media....

  11. Prolonged hypoxic culture and trypsinization increase the pro-angiogenic potential of human adipose tissue-derived stem cells

    DEFF Research Database (Denmark)

    Rasmussen, Jeppe Grøndahl; Frøbert, Ole; Pilgaard, Linda

    2011-01-01

    Transplantation of mesenchymal stromal cells (MSC), including adipose tissue-derived stem cells (ASC), is a promising option in the treatment of vascular disease. Short-term hypoxic culture of MSC augments secretion of anti-apoptotic and angiogenic cytokines. We hypothesized that prolonged hypoxic...... (1% and 5% oxygen) culture and trypsinization would augment ASC expression of anti-apoptotic and angiogenic cytokines and increase the angiogenic potential of ASC-conditioned media....

  12. Posterior Corneal Characteristics of Cataract Patients with High Myopia.

    Science.gov (United States)

    Jing, Qinghe; Tang, Yating; Qian, Dongjin; Lu, Yi; Jiang, Yongxiang

    2016-01-01

    To evaluate the characteristics of the posterior corneal surface in patients with high myopia before cataract surgery. We performed a cross-sectional study at the Eye and ENT Hospital of Fudan University, Shanghai, China. Corneal astigmatism and axial length were measured with a rotating Scheimpflug camera (Pentacam) and partial coherence interferometry (IOLMaster) in a high-myopia study group of 167 eyes (axial length ≥ 26 mm) and a control group of 150 eyes (axial length > 20 mm and myopia group than in the control group. There was no significant difference in posterior corneal astigmatism between the high-myopia study group and the control group. In the study group, the mean posterior corneal astigmatism (range 0 - -0.9 diopters) was -0.29 diopters (D) ± 0.17 standard deviations (SD). The steep corneal meridian was aligned vertically (60°-120°) in 87.43% of eyes for the posterior corneal surface, and did not change with increasing age. There was a significant correlation (r = 0.235, p = 0.002) between posterior corneal astigmatism and anterior corneal astigmatism, especially when the anterior corneal surface showed with-the-rule (WTR) astigmatism (r = 0.452, p = 0.000). There was a weak negative correlation between posterior corneal astigmatism and age (r = -0.15, p = 0.053) in the high-myopia group. Compared with total corneal astigmatism values, the anterior corneal measurements alone overestimated WTR astigmatism by a mean of 0.27 ± 0.18 D in 68.75% of eyes, underestimated against-the-rule (ATR) astigmatism by a mean of 0.41 ± 0.28 D in 88.89% of eyes, and underestimated oblique astigmatism by a mean of 0.24 ± 0.13 D in 63.64% of eyes. Posterior corneal astigmatism decreased with age and remained as ATR astigmatism in most cases of high myopia. There was a significant correlation between posterior corneal astigmatism and anterior corneal astigmatism when anterior corneal astigmatism was WTR. If posterior corneal astigmatism is not accounted for when

  13. Partial-thickness corneal tissue restoration after a chemical burn

    Directory of Open Access Journals (Sweden)

    Galan A

    2016-04-01

    Full Text Available Alessandro Galan, Anton Giulio Catania, Giuseppe Lo Giudice San Paolo Ophthalmic Center, San Antonio Hospital, Padova, Italy Purpose: We describe a case of full-thickness corneal restoration after an acute corneal burn with an acid agent. Methods: A 32-year-old male reported painful discomfort, redness, photophobia, and a decrease in visual acuity in the left eye after a unilateral burn with an acid agent. Slit-lamp examination revealed massive corneal melting involving necrotic sequestrum of the entire corneal surface. Surgical approach was carried out in order to preserve residual ocular tissues. Results: Extensive corneal–conjunctival layer curettage of the necrotic tissue was performed showing perfectly clear undamaged deep lamellar corneal layers. The patient underwent multilayered amniotic membrane transplantation and total capsular–conjunctival flap in order to preserve ocular tissue from further melting or corneal perforation. A complete and spontaneous “restitutio ad integrum” of the corneal layers was shown during the follow-up. The cornea was perfectly clear with restored normal anatomical architecture. Conclusion: In this case, a spontaneous full-thickness corneal tissue restoration occurred after an acute chemical burn. Studies about the mechanisms whereby different cells interact and replicate within the stroma may unveil the biology behind corneal regeneration and transparency. Keywords: amniotic membrane, chemical burn, corneal healing

  14. Human screams occupy a privileged niche in the communication soundscape.

    Science.gov (United States)

    Arnal, Luc H; Flinker, Adeen; Kleinschmidt, Andreas; Giraud, Anne-Lise; Poeppel, David

    2015-08-03

    Screaming is arguably one of the most relevant communication signals for survival in humans. Despite their practical relevance and their theoretical significance as innate [1] and virtually universal [2, 3] vocalizations, what makes screams a unique signal and how they are processed is not known. Here, we use acoustic analyses, psychophysical experiments, and neuroimaging to isolate those features that confer to screams their alarming nature, and we track their processing in the human brain. Using the modulation power spectrum (MPS [4, 5]), a recently developed, neurally informed characterization of sounds, we demonstrate that human screams cluster within restricted portion of the acoustic space (between ∼30 and 150 Hz modulation rates) that corresponds to a well-known perceptual attribute, roughness. In contrast to the received view that roughness is irrelevant for communication [6], our data reveal that the acoustic space occupied by the rough vocal regime is segregated from other signals, including speech, a pre-requisite to avoid false alarms in normal vocal communication. We show that roughness is present in natural alarm signals as well as in artificial alarms and that the presence of roughness in sounds boosts their detection in various tasks. Using fMRI, we show that acoustic roughness engages subcortical structures critical to rapidly appraise danger. Altogether, these data demonstrate that screams occupy a privileged acoustic niche that, being separated from other communication signals, ensures their biological and ultimately social efficiency. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Extending Mental Health Diagnostic Privileges to Social Workers in Saskatchewan

    Directory of Open Access Journals (Sweden)

    Stephanie E. Austin

    2017-05-01

    Full Text Available Bill 78, An Act to amend The Social Workers Act, was passed in 2013 in Saskatchewan, allowing social workers to diagnose mental health disorders. Social workers previously had diagnostic privileges until the Psychologists Act was passed in 2002. The goal of the reform is to reduce wait times to access mental health services and diagnoses. The reform was introduced following extensive lobbying by the Saskatchewan Association of Social Workers (SASW and during a time of increased recognition of mental health issues both provincially and nationally. The reform will be implemented using regulatory instruments through the SASW and its by-laws, however the by-laws – updated to include provisions for Authorized Practice Endorsement, or in other words diagnosis of mental health disorders – have not, to date, been implemented. Accordingly, an evaluation of the reform has also not yet been conducted. Overall this reform is expected to improve access to mental health services, however concerns remain about availability of government funding and programs for treatment and services following diagnosis.

  16. Corneal biomechanical features in patients with ankylosing spondylitis.

    Science.gov (United States)

    Cabuk, Kubra Serefoglu; Üstün, Emine Isil; Atalay, Kursat; Kirgiz, Ahmet; Aydin, Rukiye

    2017-01-01

    To evaluate the corneal biomechanical features and central corneal thickness in ankylosing spondylitis patients and to evaluate correlations of these parameters with disease activity. The study included 51 patients diagnosed with ankylosing spondylitis (mean age, 40.80 ± 13.15 years; range, 18-72 years) and 34 age- and sex-matched healthy controls (mean age, 42.00 ± 12.32 years; range, 18-60 years). All underwent a complete ophthalmological and physical examination, including visual acuity testing and biomicroscopic anterior and posterior segment examinations. Corneal hysteresis, corneal resistance factor, Goldmann-correlated intraocular pressure, and corneal compensated intraocular pressure were evaluated with an ocular response analyzer, and the central corneal thickness was measured with Sirius® corneal tomography. The Bath Ankylosing Spondylitis Disease Activity Index, Functional Index, and Metrology Index scores were recorded. In the ankylosing spondylitis patients, the mean disease duration was 7.73 ± 6.05 (range, 1-30) years. There was no statistically significant difference between the patients and controls in the corneal biomechanical features. The Goldmann-correlated intraocular pressure and corneal compensated intraocular pressure both showed positive correlations with age (p=0.003 and p=0.001, res-pectively). There was a negative correlation between corneal hysteresis and disease duration (p=0.002), and between central corneal thickness and the Bath Ankylosing Spondylitis Metrology Index score (p=0.003). This study demonstrated a significant negative correlation between corneal hysteresis and disease duration in ankylosing spondylitis patients. Furthermore, the central corneal thickness value decreased with an increase in Bath Ankylosing Spondylitis Metrology Index score, which may result in an underestimate of intraocular pressure readings and thus an inaccurate risk assessment of glaucoma.

  17. Corneal Astigmatism Stability in Descemet Membrane Endothelial Keratoplasty for Fuchs Corneal Dystrophy.

    Science.gov (United States)

    Yokogawa, Hideaki; Sanchez, P James; Mayko, Zachary M; Straiko, Michael D; Terry, Mark A

    2016-07-01

    To calculate the magnitude and angle of the shift in corneal astigmatism associated with Descemet membrane endothelial keratoplasty (DMEK) surgery to determine the feasibility of concurrent astigmatism correction at the time of DMEK triple procedures. Retrospective study. Forty-seven eyes that previously underwent the DMEK procedure for Fuchs endothelial corneal dystrophy and that had more than 1.0 diopter (D) of front corneal astigmatism preoperatively were identified. All DMEK surgeries used a clear corneal temporal incision of 3.2 mm. Surgically induced astigmatism (SIA) was evaluated 6 months postsurgery with vector analysis using Scheimpflug image reading. We did not find a difference between pre- and postoperative magnitude of front astigmatism (P = 0.88; paired t test). The magnitude of the SIA front surface was 0.77 ± 0.63 D (range, 0.10-3.14 D). The centroid vector of the SIA front surface was 0.14 at 89.3°. A hyperopic corneal power shift was noted in both the front surface by 0.26 ± 0.74 D (range, 0.45-3.05 D) (P = 0.018; paired t test) and back surface by 0.56 ± 0.55 D (range, 0.25-2.40 D) (P astigmatism that is a with-the-rule shift associated with a temporal clear corneal incision. The stability of these data from preop to postop supports the plausibility of incorporating astigmatism correction with the cautious use of toric intraocular lenses for patients with Fuchs corneal dystrophy and cataract.

  18. Long-Term Topical Ganciclovir and Corticosteroids Preserve Corneal Endothelial Function in Cytomegalovirus Corneal Endotheliitis.

    Science.gov (United States)

    Fan, Nai-Wen; Chung, Yu-Chien; Liu, Yao-Chung; Liu, Catherine Jui-Ling; Kuo, Yih-Shiuan; Lin, Pei-Yu

    2016-05-01

    To report the long-term outcomes of topical ganciclovir (GCV) and corticosteroids as a maintenance therapy for cytomegalovirus (CMV) corneal endotheliitis. This retrospective study included 10 eyes of 9 patients diagnosed with CMV corneal endotheliitis with a minimum 1-year follow-up at a tertiary referral hospital between 2008 and 2014. CMV corneal endotheliitis was defined by corneal edema associated with typical keratic precipitates (KPs) and a positive CMV polymerase chain reaction from aqueous humor taps. Patients receiving long-term topical 0.5% GCV and topical corticosteroids without discontinuation were included. The final corneal condition and endothelial cell density (ECD) were reported. The mean age was 45.6 ± 11.7 years. The mean follow-up duration was 48 ± 25 months. All patients exhibited typical coin-shaped and/or linear KPs. A significant resolution of corneal edema and decreased KPs were achieved within 1 month in all patients after initiating topical 0.5% GCV every 2 hours and topical corticosteroids twice a day. The dose frequency was gradually tapered to GCV 4 times and corticosteroids once or twice a day as a maintenance therapy. All 10 eyes had a clear graft or corneas at the end of this study. The mean ECD was 1630 ± 699 cells per millimeter square before treatment and 1776 ± 834 cells per millimeter square at the end of the study period. Topical 0.5% GCV and corticosteroids as a maintenance regimen without interruption effectively preserved long-term corneal endothelial function.

  19. Relationship between Corneal Guttae and Quality of Vision in Patients with Mild Fuchs' Endothelial Corneal Dystrophy.

    Science.gov (United States)

    Watanabe, Shinya; Oie, Yoshinori; Fujimoto, Hisataka; Soma, Takeshi; Koh, Shizuka; Tsujikawa, Motokazu; Maeda, Naoyuki; Nishida, Kohji

    2015-10-01

    To investigate the effect of the severity of corneal guttae on quality of vision (QOV) in patients with mild Fuchs' endothelial corneal dystrophy (FECD). Cross-sectional study. Twenty-three eyes of 14 patients with mild FECD without corneal edema on slit-lamp examination (5 pseudophakic eyes and 18 phakic eyes with mild lens opacity; grade 1.0-2.0 nuclear opalescence, grade 1.0-2.0 nuclear color, grade 1.0 cortical cataract, and grade 1.0 posterior subcapsular cataract on the Lens Opacities Classification System, version III). The area ratio of the corneal guttae (ARCG) in the endothelial cells was measured by multifocal specular microscopy. The QOV parameters, that is, corrected distance visual acuity (CDVA), letter contrast sensitivity (LCS), and intraocular straylight, also were measured. The correlations were assessed between the ARCG and QOV parameters and between the straylight and CDVA and LCS. The ARCG, logarithm of the minimum angle of resolution CDVA, LCS, and straylight. Univariate analysis showed that the ARCG was correlated significantly with the CDVA, LCS, and straylight (R(2) = 0.41, P = 0.001; R(2) = 0.55, P = 0.001; and R(2) = 0.39, P = 0.002, respectively). Univariate analysis also showed that straylight was correlated significantly with the CDVA and LCS (R(2) = 0.47, P = 0.001 and R(2) = 0.41, P = 0.001, respectively). Corneal guttae without edema caused the QOV to deteriorate in eyes with FECD. Patients with higher straylight had worse CDVA or LCS. Intraocular forward light scatter caused by corneal guttae may result in visual disturbances. Quantification of corneal guttae can be useful to evaluate the effect of guttae on the QOV and determine the surgical indications of endothelial keratoplasty for eyes with mild FECD. Copyright © 2015 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  20. Farmer Story: What I’ve Learned About Protecting the Privilege of Farming

    Science.gov (United States)

    An Iowa farmer describes his feeling that farming is a privilege that he wants to be available for future generations. He describes how he changed his practices to focus on water conservation after noticing algal blooms in his pond.

  1. Waiver of the psychotherapist-patient privilege: implications for child custody litigation.

    Science.gov (United States)

    Boumil, Marcia M; Freitas, Debbie F; Freitas, Cristina F

    2012-01-01

    The psychotherapist-patient privilege, rooted in both common and statutory law, is predicated upon the public policy goal of protecting the reasonable expectation of privacy of individuals seeking psychotherapy. The privilege is not absolute, however. State and federal courts are far from uniform in determining how and when the privilege should be waived, in whole or in part, through implication, inadvertence or the affirmative action of the parties. In the family law context, the law that has evolved around the exercise of this privilege is even more complex as the needs of children add another wrinkle to the goal of balancing the imperative of confidentiality with the need for useful information that may be provided.

  2. Combining angiogenic gene and stem cell therapies for myocardial infarction.

    Science.gov (United States)

    Pons, Jennifer; Huang, Yu; Takagawa, Junya; Arakawa-Hoyt, Janice; Ye, Jianqin; Grossman, William; Kan, Yuet Wai; Su, Hua

    2009-09-01

    Transplantation of stem cells from various sources into infarcted hearts has the potential to promote myocardial regeneration. However, the regenerative capacity is limited partly as a result of the low survival rate of the transplanted cells in the ischemic myocardium. In the present study, we tested the hypothesis that combining cell and angiogenic gene therapies would provide additive therapeutic effects via co-injection of bone marrow-derived mesenchymal stem cells (MSCs) with an adeno-associated viral vector (AAV), MLCVEGF, which expresses vascular endothelial growth factor (VEGF) in a cardiac-specific and hypoxia-inducible manner. MSCs isolated from transgenic mice expressing green fluorescent protein and MLCVEGF packaged in AAV serotype 1 capsid were injected into mouse hearts at the border of ischemic area, immediately after occlusion of the left anterior descending coronary, individually or together. Engrafted cells were detected and quantified by real-time polymerase chain reaction and immunostaining. Angiogenesis and infarct size were analyzed on histological and immunohistochemical stained sections. Cardiac function was analyzed by echocardiography. We found that co-injection of AAV1-MLCVEGF with MSCs reduced cell loss. Although injection of MSCs and AAV1-MLCVEGF individually improved cardiac function and reduced infarct size, co-injection of MSC and AAV1-MLCVEGF resulted in the best improvement in cardiac function as well as the smallest infarct among all groups. Moreover, injection of AAV1-MLCVEGF induced neovasculatures. Nonetheless, injection of MSCs attracted endogenous stem cell homing and increased scar thickness. Co-injection of MLCVEGF and MSCs in ischemic hearts can result in better cardiac function and MSC survival, compared to their individual injections, as a result of the additive effects of each therapy.

  3. Automated quantification reveals hyperglycemia inhibits endothelial angiogenic function.

    Directory of Open Access Journals (Sweden)

    Anthony R Prisco

    Full Text Available Diabetes Mellitus (DM has reached epidemic levels globally. A contributing factor to the development of DM is high blood glucose (hyperglycemia. One complication associated with DM is a decreased angiogenesis. The Matrigel tube formation assay (TFA is the most widely utilized in vitro assay designed to assess angiogenic factors and conditions. In spite of the widespread use of Matrigel TFAs, quantification is labor-intensive and subjective, often limiting experiential design and interpretation of results. This study describes the development and validation of an open source software tool for high throughput, morphometric analysis of TFA images and the validation of an in vitro hyperglycemic model of DM.Endothelial cells mimic angiogenesis when placed onto a Matrigel coated surface by forming tube-like structures. The goal of this study was to develop an open-source software algorithm requiring minimal user input (Pipeline v1.3 to automatically quantify tubular metrics from TFA images. Using Pipeline, the ability of endothelial cells to form tubes was assessed after culture in normal or high glucose for 1 or 2 weeks. A significant decrease in the total tube length and number of branch points was found when comparing groups treated with high glucose for 2 weeks versus normal glucose or 1 week of high glucose.Using Pipeline, it was determined that hyperglycemia inhibits formation of endothelial tubes in vitro. Analysis using Pipeline was more accurate and significantly faster than manual analysis. The Pipeline algorithm was shown to have additional applications, such as detection of retinal vasculature.

  4. Anti-angiogenic activity of inositol hexaphosphate (IP6).

    Science.gov (United States)

    Vucenik, Ivana; Passaniti, Antonino; Vitolo, Michele I; Tantivejkul, Kwanchanit; Eggleton, Paul; Shamsuddin, Abulkalam M

    2004-11-01

    A significant anticancer activity of the naturally occurring carbohydrate inositol hexaphosphate (IP(6)) has been reported against numerous cancer models. Since tumors require angiogenesis for growth and metastasis, we hypothesize that IP(6) reduces tumor growth by inhibiting angiogenesis. Because angiogenesis depends on the interaction between endothelial and tumor cells, we investigated the effect of IP(6) on both. IP(6) inhibited the proliferation and induced the differentiation of endothelial cells in vitro; the growth of bovine aortic endothelial cells (BAECs) evaluated by MTT proliferation assay was inhibited in a dose-dependent manner (IC(50) = 0.74 mM). The combination of IP(6) and vasostatin, a calreticulin fragment with anti-angiogenic activity, was synergistically superior in growth inhibition than either compound. IP(6) inhibited human umbilical vein endothelial cell (HUVEC) tube formation (in vitro capillary differentiation) on a reconstituted extracellular matrix, Matrigel, and disrupted pre-formed tubes. IP(6) significantly reduced basic fibroblast growth factor (bFGF)-induced vessel formation (P < 0.01) in vivo in Matrigel plug assay. Exposure of HepG2, a human hepatoma cell line, to IP(6) for 8 h, resulted in a dose-dependent decrease in the mRNA levels of vascular endothelial growth factor (VEGF), as assessed by RT-PCR. IP(6) treatment of HepG2 cells for 24 h also significantly reduced the VEGF protein levels in conditioned medium, in a concentration-dependent manner (P = 0.012). Thus, IP(6) has an inhibitory effect on induced angiogenesis.

  5. Interferometer for measuring dynamic corneal topography

    Science.gov (United States)

    Micali, Jason Daniel

    The cornea is the anterior most surface of the eye and plays a critical role in vision. A thin fluid layer, the tear film, coats the outer surface of the cornea and serves to protect, nourish, and lubricate the cornea. At the same time, the tear film is responsible for creating a smooth continuous surface where the majority of refraction takes place in the eye. A significant component of vision quality is determined by the shape of the cornea and stability of the tear film. It is desirable to possess an instrument that can measure the corneal shape and tear film surface with the same accuracy and resolution that is currently performed on common optical elements. A dual interferometer system for measuring the dynamic corneal topography is designed, built, and verified. The completed system is validated by testing on human subjects. The system consists of two co-aligned polarization splitting Twyman-Green interferometers designed to measure phase instantaneously. The primary interferometer measures the surface of the tear film while the secondary interferometer simultaneously tracks the absolute position of the cornea. Eye motion, ocular variation, and a dynamic tear film surface will result in a non-null configuration of the surface with respect to the interferometer system. A non-null test results in significant interferometer induced errors that add to the measured phase. New algorithms are developed to recover the absolute surface topography of the tear film and corneal surface from the simultaneous interferometer measurements. The results are high-resolution and high-accuracy surface topography measurements of the in vivo cornea that are captured at standard camera frame rates. This dissertation will cover the development and construction of an interferometer system for measuring the dynamic corneal topography of the human eye. The discussion starts with the completion of an interferometer for measuring the tear film. The tear film interferometer is part of an

  6. Corneal Graft Rejection: Incidence and Risk Factors

    Directory of Open Access Journals (Sweden)

    Alireza Baradaran-Rafii

    2008-12-01

    Full Text Available

    PURPOSE: To determine the incidence and risk factors of late corneal graft rejection after penetrating keratoplasty (PKP. METHODS: Records of all patients who had undergone PKP from 2002 to 2004 without immunosuppressive therapy other than systemic steroids and with at least one year of follow up were reviewed. The role of possible risk factors such as demographic factors, other host factors, donor factors, indications for PKP as well as type of rejection were evaluated. RESULTS: During the study period, 295 PKPs were performed on 286 patients (176 male, 110 female. Mean age at the time of keratoplasty was 38±20 (range, 40 days to 90 years and mean follow up period was 20±10 (range 12-43 months. Graft rejection occurred in 94 eyes (31.8% at an average of 7.3±6 months (range, 20 days to 39 months after PKP. The most common type of rejection was endothelial (20.7%. Corneal vascularization, regrafting, anterior synechiae, irritating sutures, active inflammation, additional anterior segment procedures, history of trauma, uncontrolled glaucoma, prior graft rejection, recurrence of herpetic infection and eccentric grafting increased the rate of rejection. Patient age, donor size and bilateral transplantation had no significant influence on graft rejection. CONCLUSION: Significant risk factors for corneal graft rejection include

  7. Corneal biomechanical properties distribution in myopic population

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    Mohammad Mirzaei

    2014-03-01

    Full Text Available AIM: To evaluate distribution of corneal biomechanical measurements in normal myopia and myopic-astigmatism population.METHODS:One hundred and eighty eyes with myopia and myopic-astigmatism candidated for laser refractive surgery were included in this study. Complete examination of anterior and posterior segments, manifest refraction spherical equivalent(MRSE, Orbscan and Zywave were performed preoperatively. Ocular response analyzer(ORAwas used to measure corneal hysteresis(CH, corneal resistance factor(CRF, Goldmann-correlated intraocular pressure(IOPgand corneal compensated IOP(IOPcc. Distribution of all corneal biomechanical properties and correlation between these parameters and MRSE, age and sex were determined. Statistical analysis was performed using SPSS 17 software and a P-Value less than 0.05 was considered significant. RESULTS: Mean age was 28.20±6.78 years. Mean MRSE was -4.21±1.19D. Mean CH, CRF, IOPg and IOPcc was 10.00±1.28mmHg, 10.17±1.45mmHg, 15.71±2.67mmHg and 16.68±2.41mmHg respectively. 28.4% of all myopic population had CH about 10mmHg, and 71% had CH, 9mmHg up to 11mmHg. CRF in 25.9% of myopic population was 10mmHg, and in 48.7% was 9mmHg up to 11mmHg. There was very poor positive correlation between MRSE& CH(Rs=0.001, P=0.71and MRSE& CRF(Rs=0.01, P=0.18.CONCLUSION: Our study demonstrated the distribution of corneal biomechanical properties(CH, CRF, IOPg, IOPccin normal myopia and myopic-astigmatism population in Iran, and confirmed that, there was no statistically significant correlation between CH, CRF and MRSE, age and sex but there was significant correlation between IOPg, IOPcc and formerly mentioned parameters.

  8. Corona sign: manifestation of peripheral corneal epithelial edema as a possible marker of the progression of corneal endothelial dysfunction.

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    Inoue, Tomoyuki; Hara, Yuko; Kobayashi, Takeshi; Zheng, Xiaodong; Suzuki, Takashi; Shiraishi, Atsushi; Ohashi, Yuichi

    2016-09-01

    To describe a characteristic form of the corona sign and its clinical relevance to the degree of corneal endothelial decompensation and investigate the underlying mechanism using a rabbit model. These observational cases include 31 patients undergoing penetrating keratoplasty (PKP) and 15 patients undergoing Descemet stripping automated endothelial keratoplasty (DSAEK) with special attention to the circumferentially developed corneal epithelial edema. We also conducted a laboratory observation of horizontal water flow in the rabbit cornea. We consistently observed the corona sign at the superior periphery during the initial stage of corneal endothelial decompensation after PKP. With progressive corneal endothelial cellular loss, the epithelial edema gradually expanded circumferentially in the periphery. The endothelial cellular density associated with the corona sign significantly (P corona sign compared with a superior corona sign. After DSAEK, however, the corneal epithelial edema subsided from the center but persisted peripherally as a corona sign in all cases. By 3 months postoperatively, the epithelial edema was confined to the superior periphery along with uneventful corneal endothelial healing. Rabbit experiments showed that total corneal endothelial decompensation decreased the horizontal intracorneal water migration (Inoue-Ohashi phenomenon) in the corneal periphery and induced peripheral corneal edema. The slit-lamp microscopic findings of the corona-like epithelial edema in the peripheral cornea are associated with the stage of corneal endothelial function. To support this, the developmental mechanism of the corona sign was demonstrated experimentally.

  9. Ciliary neurotrophic factor promotes the activation of corneal epithelial stem/progenitor cells and accelerates corneal epithelial wound healing.

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    Zhou, Qingjun; Chen, Peng; Di, Guohu; Zhang, Yangyang; Wang, Yao; Qi, Xia; Duan, Haoyun; Xie, Lixin

    2015-05-01

    Ciliary neurotrophic factor (CNTF), a well-known neuroprotective cytokine, has been found to play an important role in neurogenesis and functional regulations of neural stem cells. As one of the most innervated tissue, however, the role of CNTF in cornea epithelium remains unclear. This study was to explore the roles and mechanisms of CNTF in the activation of corneal epithelial stem/progenitor cells and wound healing of both normal and diabetic mouse corneal epithelium. In mice subjecting to mechanical removal of corneal epithelium, the corneal epithelial stem/progenitor cell activation and wound healing were promoted by exogenous CNTF application, while delayed by CNTF neutralizing antibody. In cultured corneal epithelial stem/progenitor cells, CNTF enhanced the colony-forming efficiency, stimulated the mitogenic proliferation, and upregulated the expression levels of corneal epithelial stem/progenitor cell-associated transcription factors. Furthermore, the promotion of CNTF on the corneal epithelial stem/progenitor cell activation and wound healing was mediated by the activation of STAT3. Moreover, in diabetic mice, the content of CNTF in corneal epithelium decreased significantly when compared with that of normal mice, and the supplement of CNTF promoted the diabetic corneal epithelial wound healing, accompanied with the advanced activation of corneal epithelial stem/progenitor cells and the regeneration of corneal nerve fibers. Thus, the capability of expanding corneal epithelial stem/progenitor cells and promoting corneal epithelial wound healing and nerve regeneration indicates the potential application of CNTF in ameliorating limbal stem cell deficiency and treating diabetic keratopathy. © 2014 AlphaMed Press.

  10. Combined corneal allotransplantation and vitreoretinal surgery using an Eckardt temporary keratoprosthesis: analysis for factors determining corneal allograft survival.

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    Lee, Dae Seung; Heo, Jang Won; Choi, Hyuk Jin; Kim, Mee Kum; Wee, Won Ryang; Oh, Joo Youn

    2014-01-01

    To evaluate the outcome of corneal allotransplantation in combined penetrating keratoplasty and vitreoretinal surgery using a temporary keratoprosthesis, and to determine the factors affecting corneal allograft survival. We reviewed the medical charts of eleven patients who had undergone combined corneal allotransplantation and pars plana vitrectomy using an Eckardt temporary keratoprosthesis, for the treatment of corneal opacification and vitreoretinal disease. The survival rates of the corneal grafts were assessed, and patient demographics, the diagnosis of corneal and retinal disease, the preoperative ocular characteristics, and surgical methods were compared between the group with graft survival and that with graft failure. The causes of corneal opacification were corneal laceration (four eyes), infectious keratitis (four eyes), atopic keratitis (one eye), rejected corneal graft (one eye), and uveitis-related bullous keratopathy (one eye). The preoperative diagnoses included endophthalmitis (six eyes), posterior uveitis (one eye), vitreous opacity or hemorrhage (two eyes), and rhegmatogenous retinal detachment (two eyes). The survival rate of the corneal allografts was 27.3% (3/11 eyes). The mean survival time was 391 days during the mean follow-up period of 687 days. The retinal surgery was successful in 81.8% (9/11 eyes) of cases. The presence of active inflammation in the cornea at the time of surgery was significantly correlated with graft rejection (P=0.004). Other factors, including age, the presence of glaucoma, type of corneal and retinal disease, or type of retinal surgery, such as silicone oil injection and gas tamponade, had no significant correlation with graft rejection. Combined corneal allotransplantation and pars plana vitrectomy using a temporary keratoprosthesis allowed for successful surgical intervention in vitreoretinal disease. However, only 27.3% of corneal allografts survived, depending on the presence of active inflammation in the

  11. Effects of aberrant Pax6 gene dosage on mouse corneal pathophysiology and corneal epithelial homeostasis.

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    Richard L Mort

    Full Text Available Altered dosage of the transcription factor PAX6 causes multiple human eye pathophysiologies. PAX6⁺/⁻ heterozygotes suffer from aniridia and aniridia-related keratopathy (ARK, a corneal deterioration that probably involves a limbal epithelial stem cell (LESC deficiency. Heterozygous Pax6(+/Sey-Neu (Pax6⁺/⁻ mice recapitulate the human disease and are a good model of ARK. Corneal pathologies also occur in other mouse Pax6 mutants and in PAX77(Tg/- transgenics, which over-express Pax6 and model human PAX6 duplication.We used electron microscopy to investigate ocular defects in Pax6⁺/⁻ heterozygotes (low Pax6 levels and PAX77(Tg/- transgenics (high Pax6 levels. As well as the well-documented epithelial defects, aberrant Pax6 dosage had profound effects on the corneal stroma and endothelium in both genotypes, including cellular vacuolation, similar to that reported for human macular corneal dystrophy. We used mosaic expression of an X-linked LacZ transgene in X-inactivation mosaic female (XLacZ(Tg/- mice to investigate corneal epithelial maintenance by LESC clones in Pax6⁺/⁻ and PAX77(Tg/- mosaic mice. PAX77(Tg/- mosaics, over-expressing Pax6, produced normal corneal epithelial radial striped patterns (despite other corneal defects, suggesting that centripetal cell movement was unaffected. Moderately disrupted patterns in Pax6⁺/⁻ mosaics were corrected by introducing the PAX77 transgene (in Pax6⁺/⁻, PAX77(Tg/- mosaics. Pax6(Leca4/+, XLacZ(Tg/- mosaic mice (heterozygous for the Pax6(Leca4 missense mutation showed more severely disrupted mosaic patterns. Corrected corneal epithelial stripe numbers (an indirect estimate of active LESC clone numbers declined with age (between 15 and 30 weeks in wild-type XLacZ(Tg/- mosaics. In contrast, corrected stripe numbers were already low at 15 weeks in Pax6⁺/⁻ and PAX77(Tg/- mosaic corneas, suggesting Pax6 under- and over-expression both affect LESC clones.Pax6⁺/⁻ and PAX77(Tg

  12. Maternal plasma angiogenic and inflammatory factor profiling in foetal Down syndrome.

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    Monika Zbucka-Kretowska

    Full Text Available Angiogenic factors are proteins that are related to certain foetal chromosomal abnormalities. The aim of this study was to determine the concentration of 60 angiogenic factors in the plasma of women with offspring possessing trisomy 21/Down syndrome (DS.After analysing karyotyping results, we selected 20 patients with foetuses possessing DS, and for the control group, we selected 28 healthy patients with uncomplicated pregnancies who delivered healthy newborns at term (i.e., 15-18 weeks of gestation. To assess the concentration of proteins in the blood plasma, we used a protein macroarray which enabled simultaneous determination of 60 angiogenic factors per sample.We observed a statistically significant increase in the concentration of these five angiogenic and inflammatory factors: TGFb1 (p = 0.039, angiostatin (p = 0.0142, I-309 (p = 0.0476, TGFb3 (p = 0.0395, and VEGF-D (p = 0.0173-compared to concentrations in patients with healthy foetuses.Our findings suggest that angiogenic factors may play role in DS pathogenesis.

  13. Assessment of anti-angiogenic and anti-tumoral potentials of Origanum onites L. essential oil.

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    Bostancıoğlu, Rakibe Beklem; Kürkçüoğlu, Mine; Başer, Kemal Hüsnü Can; Koparal, Ayşe Tansu

    2012-06-01

    Medicinal plants and culinary herbs with anti-angiogenic and little toxicity properties have gained importance. Non-toxic anti-angiogenic phytochemicals are useful in combating cancer by preventing the formation of new blood vessels to support the tumor growth. We have investigated the essential oil of Origanum onites L. (OOEO), for a possible anti-angiogenic activity. OOEO was analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC/MS). The anti-proliferative activities (by MTT assay, 3-(4,5-dimethyl-2-thiazol)-2,5-diphenyl-2H-tetrazolium bromide), anti-angiogenic activities (by tube formation assay), cell migration inhibiting capability (migration assay) and apoptotic potential (DAPI staining) of OOEO were evaluated on rat adipose tissue endothelial cells (RATECs) and 5RP7 (c-H-ras transformed rat embryonic fibroblasts) cells. Our results revealed that OOEO could markedly inhibit cell viability and induced apoptosis of 5RP7 cells and also could block in vitro tube formation and migration of RATEC. These results imply that OOEO having anti-angiogenic activity might be useful in preventing angiogenesis-related diseases and in combating cancer. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Keratoconus-integrated characterization considering anterior corneal aberrations, internal astigmatism, and corneal biomechanics.

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    Alió, Jorge L; Piñero, David P; Alesón, Alicia; Teus, Miguel A; Barraquer, Rafael I; Murta, Joaquim; Maldonado, Miguel J; Castro de Luna, Gracia; Gutiérrez, Ramón; Villa, César; Uceda-Montanes, Antonio

    2011-03-01

    To evaluate the clinical features of keratoconus taking into consideration anterior corneal aberrations, internal astigmatism, and corneal biomechanical properties and to define a new grading system based on visual limitation. Vissum Corporation, Alicante, Spain. Retrospective case series. This multicenter study comprised consecutive keratoconic eyes with no previous ocular surgery or active ocular disease. Visual, refractive, corneal topography, and pachymetry outcomes were analyzed. Internal astigmatism was calculated by vectorial analysis. Corneal aberrations and corneal biomechanics characterized by the Ocular Response Analyzer were evaluated in some eyes. Correlations between clinical data and a linear multiple regression analysis for characterizing the relationship between visual limitation and objective clinical data were performed. This study comprised 776 eyes of 507 patients (age range 11 to 79 years) The mean keratometry (K) correlated significantly with logMAR corrected distance visual acuity (CDVA) (r = 0.591, Paberrations between 4 groups differentiated by visual limitation (Pcorneas and allowed development of a new grading system for this condition. Copyright © 2011 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  15. Corneal Biomechanical Assessment Using Corneal Visualization Scheimpflug Technology in Keratoconic and Normal Eyes

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    Lei Tian

    2014-01-01

    Full Text Available Purpose. To compare the corneal biomechanical properties of keratoconic patients and age-matched controls using corneal visualization Scheimpflug technology (Corvis ST. Methods. Sixty keratoconic eyes from 47 keratoconus patients and 60 normal eyes from 60 controls were enrolled in this prospective study. Tomography and biomechanical parameters of all eyes were obtained with the Pentacam and Corvis ST, respectively. Intraocular pressure was measured using a Goldmann applanation tonometer. Results. The tomography and biomechanical parameters of the keratoconic corneas were significantly different from those of the normal corneas except for the anterior chamber angle, first applanation length, the highest concavity time, and peak distance. The deformation amplitude was the best predictive parameter (area under the curve: 0.882, with a sensitivity of 81.7%, although there was a significant overlap between keratoconic and normal corneas that ranged from 1.0 to 1.4 mm. In both the keratoconus and control groups, the deformation amplitude was negatively correlated with intraocular pressure, central corneal thickness, and corneal volume at 3 and 5 mm. Conclusions. Corvis ST offers an alternative method for measuring corneal biomechanical properties. The possibility of classifying keratoconus based on deformation amplitude deserves clinical attention.

  16. Effect of DATS on experimental corneal neovascularization induced by corneal suture in rats cornea

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    Xiao-Jun Zhou

    2017-11-01

    Full Text Available AIM: To study the effect of diallyl trisulfide(DATSon experimental corneal neovascularization(CNVin rats induced by corneal suture and detect the expression of vascular endothelial growth factor(VEGFand p-AKT in rats cornea. METHODS: The rat model of corneal neovascularization(CNVwas induced by corneal suture. Rats were randomly divided into Group A: physiological saline control group containing DMSO(10 rats; Group B: 25μmol/L DATS treatment group(10 rats; Group C: 50μmol/L DATS treatment group(10 rats; Group D: 100μmol/L DATS treatment group(10 rats; Group E: 200μmol/L DATS treatment group(10 rats. The occurrence and development of CNV were observed by slit-lamp microscope at 7d after suture, and the area of CNV were calculated.Two weeks later, HE staining was used to observe the pathological organization form of each cornea, and RT-PCR and Western blot were used to detect the expression of VEGF mRNA and protein expression of VEGF and p-AKT between each groups. RESULTS: The blood vessel area of Group C, D and E was compared with that of Group A, the difference was statistically significant(PPPCONCLUSION: DATS can inhibit corneal neovascularization of the rats induced by suture. Its mechanism may be associated with suppression of VEGF secretion, down-regulation of VEGF and inactivation of p-AKT.

  17. Corneal Shape, Volume, and Interocular Symmetry: Parameters to Optimize the Design of Biosynthetic Corneal Substitutes.

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    Durr, Georges M; Auvinet, Edouard; Ong, Jeb; Meunier, Jean; Brunette, Isabelle

    2015-07-01

    To characterize the three-dimensional (3D) shape, volume distribution, and mirror symmetry of the right and left corneas at the scale of a large population, based on the integrated analysis of 3D corneal shape average maps and topography parameters. A total of 7670 Orbscan II corneal topographies from 3835 consenting subjects with no history of ocular disease were studied. Average topography maps were created using the right and left corneal topographies of all subjects. To quantify symmetry, left eye topographies were flipped horizontally into "right eye" topographies and statistics maps were generated, including difference and intraclass correlation coefficient (ICC) maps. The standard deviation of the anterior and posterior average elevation maps in the 3-mm radius central zone of the right and left corneas ranged within ± 8 μm and ± 44 μm, respectively. The ICC maps showed almost perfect interocular agreement for anterior elevation, posterior elevation, and pachymetry (all ICCs > 0.96). All studied shape parameters also showed excellent agreement (ICCs ≥ 0.80). Mirror symmetry was not affected by age, sex, or spherical equivalent. We also showed that this horizontal reflection (flip) of the right and left corneal shapes could not be replaced by a simple rotation. These results indicate that in normal eyes, the anterior elevation, posterior elevation, and pachymetry of the right and left corneas show remarkable symmetry. This comprehensive analysis was achieved with the purpose of guiding the development of future biosynthetic corneal substitutes.

  18. Relationship between corneal biomechanical properties, central corneal thickness, and intraocular pressure across the spectrum of glaucoma.

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    Kaushik, Sushmita; Pandav, Surinder Singh; Banger, Anupam; Aggarwal, Kanika; Gupta, Amod

    2012-05-01

    To evaluate corneal biomechanical properties across the glaucoma spectrum and study the relationship between these measurements and intraocular pressure measured by Goldmann applanation tonometry (GAT-IOP) and central corneal thickness (CCT). Prospective cross-sectional study. Tertiary-care teaching institute. A total of 323 eyes of 323 participants (71 normal, 101 glaucoma suspect [GS], 38 ocular hypertension [OHT], 59 primary angle-closure disease [PACD], 36 primary open-angle glaucoma [POAG], and 18 normal-tension glaucoma [NTG]) who had received no ophthalmic treatment. Corneal hysteresis (CH), corneal resistance factor (CRF), corneal-compensated IOP (IOPcc), and Goldmann-correlated IOP (IOPg) measured by the Ocular Response Analyzer (ORA). GAT-IOP and CCT recorded in all subjects. Regression analysis used to determine the relationship between GAT-IOP, CCT, age, CRF, and CH. Bland-Altman plots used to assess agreement between IOP measured by GAT and the ORA (IOPg). CH measurements were significantly less in POAG and NTG compared to normal subjects (P = .034 and P = .030 respectively), regardless of the IOP. The CRF was significantly less in NTG and maximum in POAG and OHT. Regression analysis with CH as dependant variable showed significant association with GAT-IOP and CRF (P glaucoma. CRF appears to influence GAT-IOP measurements more than simple geometric thickness measured by CCT. However, IOP measurements from the ORA are not interchangeable with, and are unlikely to replace, Goldmann applanation tonometry at the present time. Copyright © 2012 Elsevier Inc. All rights reserved.

  19. Spontaneous corneal melting during pregnancy: a case report.

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    Oh, Joo Youn; Kim, Mee Kum; Park, Joong Shin; Wee, Won Ryang

    2009-05-26

    Biomechanical changes in the cornea during pregnancy might lead to pathological conditions such as corneal perforation or melting. A 33-year-old Asian female who underwent penetrating keratoplasty in both eyes developed corneal melting in the right eye and marginal keratitis in the left eye in her fifth month of pregnancy. Marginal keratitis in the left eye immediately subsided with topical steroid therapy. However, spontaneous corneal melting progressed in the right eye, despite oral steroid therapy and amniotic membrane transplantation. We performed tectonic penetrating keratoplasty and corneoscleral grafting in the right eye. We advise caution in the ophthalmologic care of pregnant patients who have preexisting corneal thinning disorders or who have undergone multiple corneal surgeries, because physiologic changes during pregnancy might contribute to corneal changes leading to spontaneous melting especially in patients with compromised cornea.

  20. Systemic immunomodulatory strategies in high-risk corneal transplantation

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    Tulio B Abud

    2017-01-01

    Full Text Available The cornea is the most commonly transplanted tissue in the body. Although corneal grafts generally have high success rates, transplantation onto inflamed and vascularized host beds, or so-called high-risk corneal transplantation, has a high rate of graft rejection. The management of this high-risk corneal transplantation is challenging and involves numerous measures. One of the key measures to prevent graft rejection in these cases is the use of systemic immunosuppressive agents. In this article, we will review the systemic immunosuppressive agents most commonly used for high-risk corneal transplantation, which include corticosteroids, cysclosporine A, tacrolimus, mycophenolate mofetil, and rapamycin. Benefits, risks, and published data on the use of these medications for high-risk corneal transplantation will be detailed. We will also summarize novel immunoregulatory approaches that may be used to prevent graft rejection in high-risk corneal transplantation.