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Sample records for affecting retinal vascular

  1. The Electroretinogram in Patients with Retinal Vascular Occlusion

    Institute of Scientific and Technical Information of China (English)

    Shizhou Huang; Lezheng Wu; Taiqing Luo; De-Zheng Wu; Futian Jiang; Guangwei Luo; Juanmei Ma

    2001-01-01

    Purpose: to measure and analyze the electroretinogram (ERG) in patients with retinal vascular occlusion. Method: fifty-eight cases (59 eyes) of retinal vascular occlusion and the fellow eyes of 47 cases were tested with Ganzfeld ERG. The scotopic and photopic ERG, and oscillatory potentials were tested according to the ERG standard of ISCEV. Results: The abnormal rates of Ops and b wave were higher in retinal vascular occlusion. The abnormal ERG appeared mostly in CRVO among four types of retinal vascular occlusion. The comparisons of some amplitudes and latencies between the fellow eyes and the affected eyes showed statistically significant difference. Conclusion: The oscillatory potentials and b waves have important roles in evaluating the retinal function of patients with retinal vascular occlusions. There are some clinical significance for comparing ERG between the affected eye and the fellow eye. Eye Science 2001; 17: 50 ~ 53.

  2. Admixture mapping scans identify a locus affecting retinal vascular caliber in hypertensive African Americans: the Atherosclerosis Risk in Communities (ARIC study.

    Directory of Open Access Journals (Sweden)

    Ching-Yu Cheng

    2010-04-01

    Full Text Available Retinal vascular caliber provides information about the structure and health of the microvascular system and is associated with cardiovascular and cerebrovascular diseases. Compared to European Americans, African Americans tend to have wider retinal arteriolar and venular caliber, even after controlling for cardiovascular risk factors. This has suggested the hypothesis that differences in genetic background may contribute to racial/ethnic differences in retinal vascular caliber. Using 1,365 ancestry-informative SNPs, we estimated the percentage of African ancestry (PAA and conducted genome-wide admixture mapping scans in 1,737 African Americans from the Atherosclerosis Risk in Communities (ARIC study. Central retinal artery equivalent (CRAE and central retinal vein equivalent (CRVE representing summary measures of retinal arteriolar and venular caliber, respectively, were measured from retinal photographs. PAA was significantly correlated with CRVE (rho = 0.071, P = 0.003, but not CRAE (rho = 0.032, P = 0.182. Using admixture mapping, we did not detect significant admixture association with either CRAE (genome-wide score = -0.73 or CRVE (genome-wide score = -0.69. An a priori subgroup analysis among hypertensive individuals detected a genome-wide significant association of CRVE with greater African ancestry at chromosome 6p21.1 (genome-wide score = 2.31, locus-specific LOD = 5.47. Each additional copy of an African ancestral allele at the 6p21.1 peak was associated with an average increase in CRVE of 6.14 microm in the hypertensives, but had no significant effects in the non-hypertensives (P for heterogeneity <0.001. Further mapping in the 6p21.1 region may uncover novel genetic variants affecting retinal vascular caliber and further insights into the interaction between genetic effects of the microvascular system and hypertension.

  3. Red blood cells in retinal vascular disorders.

    Science.gov (United States)

    Agrawal, Rupesh; Sherwood, Joseph; Chhablani, Jay; Ricchariya, Ashutosh; Kim, Sangho; Jones, Philip H; Balabani, Stavroula; Shima, David

    2016-01-01

    Microvascular circulation plays a vital role in regulating physiological functions, such as vascular resistance, and maintaining organ health. Pathologies such as hypertension, diabetes, or hematologic diseases affect the microcirculation posing a significant risk to human health. The retinal vasculature provides a unique window for non-invasive visualisation of the human circulation in vivo and retinal vascular image analysis has been established to predict the development of both clinical and subclinical cardiovascular, metabolic, renal and retinal disease in epidemiologic studies. Blood viscosity which was otherwise thought to play a negligible role in determining blood flow based on Poiseuille's law up to the 1970s has now been shown to play an equally if not a more important role in controlling microcirculation and quantifying blood flow. Understanding the hemodynamics/rheology of the microcirculation and its changes in diseased states remains a challenging task; this is due to the particulate nature of blood, the mechanical properties of the cells (such as deformability and aggregability) and the complex architecture of the microvasculature. In our review, we have tried to postulate a possible role of red blood cell (RBC) biomechanical properties and laid down future framework for research related to hemorrheological aspects of blood in patients with retinal vascular disorders.

  4. Laminins and retinal vascular development.

    Science.gov (United States)

    Edwards, Malia M; Lefebvre, Olivier

    2013-01-01

    The mechanisms controlling vascular development, both normal and pathological, are not yet fully understood. Many diseases, including cancer and diabetic retinopathy, involve abnormal blood vessel formation. Therefore, increasing knowledge of these mechanisms may help develop novel therapeutic targets. The identification of novel proteins or cells involved in this process would be particularly useful. The retina is an ideal model for studying vascular development because it is easy to access, particularly in rodents where this process occurs post-natally. Recent studies have suggested potential roles for laminin chains in vascular development of the retina. This review will provide an overview of these studies, demonstrating the importance of further research into the involvement of laminins in retinal blood vessel formation.

  5. Admixture Mapping Scans Identify a Locus Affecting Retinal Vascular Caliber in Hypertensive African Americans: The Atherosclerosis Risk in Communities (ARIC) Study

    OpenAIRE

    Ching-Yu Cheng; David Reich; Wong, Tien Y.; Ronald Klein; Klein, Barbara E K; Nick Patterson; Arti Tandon; Man Li; Eric Boerwinkle; A Richey Sharrett; W H Linda Kao

    2010-01-01

    Retinal vascular caliber provides information about the structure and health of the microvascular system and is associated with cardiovascular and cerebrovascular diseases. Compared to European Americans, African Americans tend to have wider retinal arteriolar and venular caliber, even after controlling for cardiovascular risk factors. This has suggested the hypothesis that differences in genetic background may contribute to racial/ethnic differences in retinal vascular caliber. Using 1,365 a...

  6. Laser speckle analysis of retinal vascular dynamics

    DEFF Research Database (Denmark)

    Neganova, Anastasiia Y.; Postnov, Dmitry D.; Jacobsen, Jens Christian B.;

    2016-01-01

    Studies of vascular responses are usually performed on isolated vessels or on single vessels in vivo. This allows for precise measurements of diameter or blood flow. However, dynamical responses of the whole microvascular network are difficult to access experimentally. We suggest to use full......-field laser speckle imaging to evaluate vascular responses of the retinal network. Image segmentation and vessel recognition algorithms together with response mapping allow us to analyze diameter changes and blood flow responses in the intact retinal network upon systemic administration of the vasoconstrictor...

  7. Admixture mapping scans identify a locus affecting retinal vascular caliber in hypertensive African Americans: the Atherosclerosis Risk in Communities (ARIC) study.

    Science.gov (United States)

    Cheng, Ching-Yu; Reich, David; Wong, Tien Y; Klein, Ronald; Klein, Barbara E K; Patterson, Nick; Tandon, Arti; Li, Man; Boerwinkle, Eric; Sharrett, A Richey; Kao, W H Linda

    2010-04-15

    Retinal vascular caliber provides information about the structure and health of the microvascular system and is associated with cardiovascular and cerebrovascular diseases. Compared to European Americans, African Americans tend to have wider retinal arteriolar and venular caliber, even after controlling for cardiovascular risk factors. This has suggested the hypothesis that differences in genetic background may contribute to racial/ethnic differences in retinal vascular caliber. Using 1,365 ancestry-informative SNPs, we estimated the percentage of African ancestry (PAA) and conducted genome-wide admixture mapping scans in 1,737 African Americans from the Atherosclerosis Risk in Communities (ARIC) study. Central retinal artery equivalent (CRAE) and central retinal vein equivalent (CRVE) representing summary measures of retinal arteriolar and venular caliber, respectively, were measured from retinal photographs. PAA was significantly correlated with CRVE (rho = 0.071, P = 0.003), but not CRAE (rho = 0.032, P = 0.182). Using admixture mapping, we did not detect significant admixture association with either CRAE (genome-wide score = -0.73) or CRVE (genome-wide score = -0.69). An a priori subgroup analysis among hypertensive individuals detected a genome-wide significant association of CRVE with greater African ancestry at chromosome 6p21.1 (genome-wide score = 2.31, locus-specific LOD = 5.47). Each additional copy of an African ancestral allele at the 6p21.1 peak was associated with an average increase in CRVE of 6.14 microm in the hypertensives, but had no significant effects in the non-hypertensives (P for heterogeneity retinal vascular caliber and further insights into the interaction between genetic effects of the microvascular system and hypertension.

  8. Retinal Vascular Fractals and Cognitive Impairment

    Directory of Open Access Journals (Sweden)

    Yi-Ting Ong

    2014-08-01

    Full Text Available Background: Retinal microvascular network changes have been found in patients with age-related brain diseases such as stroke and dementia including Alzheimer's disease. We examine whether retinal microvascular network changes are also present in preclinical stages of dementia. Methods: This is a cross-sectional study of 300 Chinese participants (age: ≥60 years from the ongoing Epidemiology of Dementia in Singapore study who underwent detailed clinical examinations including retinal photography, brain imaging and neuropsychological testing. Retinal vascular parameters were assessed from optic disc-centered photographs using a semiautomated program. A comprehensive neuropsychological battery was administered, and cognitive function was summarized as composite and domain-specific Z-scores. Cognitive impairment no dementia (CIND and dementia were diagnosed according to standard diagnostic criteria. Results: Among 268 eligible nondemented participants, 78 subjects were categorized as CIND-mild and 69 as CIND-moderate. In multivariable adjusted models, reduced retinal arteriolar and venular fractal dimensions were associated with an increased risk of CIND-mild and CIND-moderate. Reduced fractal dimensions were associated with poorer cognitive performance globally and in the specific domains of verbal memory, visuoconstruction and visuomotor speed. Conclusion: A sparser retinal microvascular network, represented by reduced arteriolar and venular fractal dimensions, was associated with cognitive impairment, suggesting that early microvascular damage may be present in preclinical stages of dementia.

  9. Molecular pathogenesis of retinal and choroidal vascular diseases.

    Science.gov (United States)

    Campochiaro, Peter A

    2015-11-01

    There are two major types of ocular neovascularization that affect the retina, retinal neovascularization (NV) and subretinal or choroidal NV. Retinal NV occurs in a group of diseases referred to as ischemic retinopathies in which damage to retinal vessels results in retinal ischemia. Most prevalent of these are diabetic retinopathy and retinal vein occlusions. Subretinal and choroidal NV occur in diseases of the outer retina and Bruch's membrane, the most prevalent of which is age-related macular degeneration. Numerous studies in mouse models have helped to elucidate the molecular pathogenesis underlying retinal, subretinal, and choroidal NV. There is considerable overlap because the precipitating event in each is stabilization of hypoxia inducible factor-1 (HIF-1) which leads to upregulation of several hypoxia-regulated gene products, including vascular endothelial growth factor (VEGF), angiopoietin 2, vascular endothelial-protein tyrosine phosphatase (VE-PTP), and several others. Stimulation of VEGF signaling and suppression of Tie2 by angiopoietin 2 and VE-PTP are critical for sprouting of retinal, subretinal, and choroidal NV, with perturbation of Bruch's membrane also needed for the latter. Additional HIF-1-regulated gene products cause further stimulation of the NV. It is difficult to model macular edema in animals and therefore proof-of-concept clinical trials were done and demonstrated that VEGF plays a central role and that suppression of Tie2 is also important. Neutralization of VEGF is currently the first line therapy for all of the above disease processes, but new treatments directed at some of the other molecular targets, particularly stabilization of Tie2, are likely to provide additional benefit for subretinal/choroidal NV and macular edema. In addition, the chronicity of these diseases as well as the implication of VEGF as a cause of retinal nonperfusion and progression of background diabetic retinopathy make sustained delivery approaches for VEGF

  10. Retinal vascular oximetry during ranibizumab treatment of central retinal vein occlusion

    DEFF Research Database (Denmark)

    Traustason, Sindri; la Cour, Morten; Larsen, Michael

    2014-01-01

    PURPOSE: To investigate the effect of intravitreal injections of the vascular endothelial growth factor inhibitor ranibizumab on retinal oxygenation in patients with central retinal vein occlusion (CRVO). METHODS: Retinal oxygen saturation in patients with CRVO was analysed using the Oxymap Retin...

  11. Retinal vascular tree reconstruction with anatomical realism.

    Science.gov (United States)

    Lin, Kai-Shun; Tsai, Chia-Ling; Tsai, Chih-Hsiangng; Sofka, Michal; Chen, Shih-Jen; Lin, Wei-Yang

    2012-12-01

    Motivated by the goals of automatically extracting vessel segments and constructing retinal vascular trees with anatomical realism, this paper presents and analyses an algorithm that combines vessel segmentation and grouping of the extracted vessel segments. The proposed method aims to restore the topology of the vascular trees with anatomical realism for clinical studies and diagnosis of retinal vascular diseases, which manifest abnormalities in either venous and/or arterial vascular systems. Vessel segments are grouped using extended Kalman filter which takes into account continuities in curvature, width, and intensity changes at the bifurcation or crossover point. At a junction, the proposed method applies the minimum-cost matching algorithm to resolve the conflict in grouping due to error in tracing. The system was trained with 20 images from the DRIVE dataset, and tested using the remaining 20 images. The dataset contained a mixture of normal and pathological images. In addition, six pathological fluorescein angiogram sequences were also included in this study. The results were compared against the groundtruth images provided by a physician, achieving average success rates of 88.79% and 90.09%, respectively.

  12. Retinal vascular and structural dynamics during acute hyperglycaemia

    DEFF Research Database (Denmark)

    Klefter, Oliver N; Vilsbøll, Tina; Knop, Filip K;

    2015-01-01

    PURPOSE: To compare retinal vascular dynamics during acute hyperglycaemia in patients with type 2 diabetes and healthy volunteers. METHODS: Twenty-one patients with type 2 diabetes and 27 healthy controls were examined with fundus photographic measurement of retinal vessel diameters, retinal oxim...

  13. Cell Therapy Applications for Retinal Vascular Diseases: Diabetic Retinopathy and Retinal Vein Occlusion.

    Science.gov (United States)

    Park, Susanna S

    2016-04-01

    Retinal vascular conditions, such as diabetic retinopathy and retinal vein occlusion, remain leading causes of vision loss. No therapy exists to restore vision loss resulting from retinal ischemia and associated retinal degeneration. Tissue regeneration is possible with cell therapy. The goal would be to restore or replace the damaged retinal vasculature and the retinal neurons that are damaged and/or degenerating from the hypoxic insult. Currently, various adult cell therapies have been explored as potential treatment. They include mesenchymal stem cells, vascular precursor cells (i.e., CD34+ cells, hematopoietic cells or endothelial progenitor cells), and adipose stromal cells. Preclinical studies show that all these cells have a paracrine trophic effect on damaged ischemic tissue, leading to tissue preservation. Endothelial progenitor cells and adipose stromal cells integrate into the damaged retinal vascular wall in preclinical models of diabetic retinopathy and ischemia-reperfusion injury. Mesenchymal stem cells do not integrate as readily but appear to have a primary paracrine trophic effect. Early phase clinical trials have been initiated and ongoing using mesenchymal stem cells or autologous bone marrow CD34+ cells injected intravitreally as potential therapy for diabetic retinopathy or retinal vein occlusion. Adipose stromal cells or pluripotent stem cells differentiated into endothelial colony-forming cells have been explored in preclinical studies and show promise as possible therapies for retinal vascular disorders. The relative safety or efficacy of these various cell therapies for treating retinal vascular disorders have yet to be determined.

  14. Relationship between retinal vascular occlusions and incident cerebrovascular diseases

    Science.gov (United States)

    Zhou, Yue; Zhu, Wengen; Wang, Changyun

    2016-01-01

    Abstract Several studies investigating the role of retinal vascular occlusions, on cerebrovascular diseases (CVD) have been reported, but the results are still inconsistent. We therefore sought to evaluate the relationship between retinal vascular occlusions and CVD. We systematically searched the Cochrane Library, PubMed, and ScienceDirect databases through January 31, 2016 for studies evaluating the effect of retinal vascular occlusions on the risk of CVD. Data were abstracted using predefined criteria, and then pooled by RevMan 5.3 software. A total of 9 retrospective studies were included in this meta-analysis. When compared with individuals without retinal vascular occlusions, both individuals with retinal artery occlusion (RAO) (odds ratio [OR] = 2.01, 95% confidence interval [CI]: 1.21–3.34; P = 0.005) and individuals with retinal vein occlusion (RVO) (OR = 1.37, 95% CI: 1.24–1.50; P < 0.00001) had higher risks of developing CVD. Additionally, both individuals with central retinal artery occlusion (CRAO) (OR = 2.00, 95% CI: 1.12–3.56; P = 0.02) and branch retinal artery occlusion (BRAO) (OR = 1.60, 95% CI: 1.03–1.48; P = 0.04) were significantly associated with increased risk of CVD. Published literatures support both RVO and RAO are associated with increased risks of CVD. Further prospective studies are needed to confirm these findings. PMID:27368050

  15. Vascular endothelial growth factor blocking agents in retinal vein occlusion

    Directory of Open Access Journals (Sweden)

    Chris Canning

    2008-01-01

    Full Text Available This paper summarises the current status of the use of vascular endothelial growth factor (VEGF blocking agents in retinal vein occlusion. There have been no randomised controlled trials comparing this treatment with the current standard treatment (largely laser so the lower grade evidence of single treatment case series and anecdotal reports are discussed. VEGF blockers are good at reducing macular oedema in the short term, do improve visual acuity in many cases, and do not seem to adversely affect the long term revascularisation that is necessary to overcome the vein occlusion. VEGF blocking agents are not used in isolation in this condition - they will remain an adjunct to systemic and other local treatments. The literature was reviewed in online searches of Embase and Ovid and the papers quoted are a representative sample of a larger body of publications.

  16. UNILATERAL RETINAL VASCULAR MALFORMATION IN HEREDITARY HEMORRHAGIC TELANGIECTASIA

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    Ananth Bhandary

    2014-07-01

    Full Text Available Hereditary hemorrhagic telangeiectasia (HHT is an autosomal dominant genetic disorder that leads to vascular malformations. It was first recognized in the 19th century as a familial disorder with abnormal vascular structures causing bleeding from the nose and gastrointestinal tract. HHT is characterized by telangiectatic lesions of the nose, lips, lungs, brain, and spinal cord. The reported incidence in Europe and Japan is between 1:5000 and 1:8000; but is widely variable in other regions. It is seen more frequently in whites. Ocular involvement has been reported in patients with HHT. Although conjunctival telangiectasia is the most common manifestation, rarely intraocular vascular lesions such as retinal telangiectasia and arteriovenous malformations in the retina, are seen. We describe a patient with HHT who had an abnormal unilateral retinal vascular abnormality along with tortuous conjunctival vasculature in the other eye, which has not been reported till date

  17. Familial correlation of retinal vascular caliber in Singapore Chinese

    NARCIS (Netherlands)

    L.-J. Li (Ling-Jun); J. Liao (Jie); Q. Fan (Qiao); C.Y.-L. Cheung (Carol Yim-Lui); M.K. Ikram (Kamran); C-Y. Cheng (Ching-Yu); S-M. Saw (Seang-Mei); T.Y. Wong (Tien)

    2013-01-01

    textabstractPurpose. Our study aimed to explore the heritability of retinal vascular caliber among Singapore Chinese families. Methods. In the Strabismus, Amblyopia, and Refractive Error Study in Singaporean Chinese Preschoolers (STARS) family study conducted from 2008 to 2010, a total of 727 partic

  18. Hypoxia-inducible factor and vascular endothelial growth factor in the neuroretina and retinal blood vessels after retinal ischemia

    DEFF Research Database (Denmark)

    Håkansson, Gisela; Gesslein, Bodil; Gustafsson, Lotta

    2010-01-01

    Retinal ischemia arises from circulatory failure. As the retinal blood vessels are key organs in circulatory failure, our aim was to study the retinal vasculature separately from the neuroretina to elucidate the role of hypoxia-inducible factor (HIF) 1α and 1β and vascular endothelial growth factor...

  19. Effect of birth parameters on retinal vascular caliber: the Twins Eye Study in Tasmania.

    Science.gov (United States)

    Sun, Cong; Ponsonby, Anne-Louise; Wong, Tien Y; Brown, Shayne A; Kearns, Lisa S; Cochrane, Jenny; MacKinnon, Jane R; Ruddle, Jonathan B; Hewitt, Alex W; Liew, Gerald; Dwyer, Terence; Scurrah, Katrina; Mackey, David A

    2009-03-01

    Recent studies reported an association between smaller birth size and narrower retinal vascular caliber, but it remains unclear whether this association is attributed to confounding by shared environment or genetic factors. At a mean age of 9.3 years, 266 twins (49 monozygotic and 84 dizygotic pairs) in the Twins Eye Study in Tasmania underwent an ophthalmic examination including retinal photography. Retinal vascular caliber was measured using a validated protocol. The majority of these twins were also in the Tasmanian Infant Health Study, which prospectively collected data on birth parameters and antenatal maternal factors. We conducted the main analysis using linear mixed models, accounting for birth set clustering. Both the within-pair (-9.73; 95% CI: -14.68 to -4.77 microm per 5-cm decrease in birth length) and between-pair associations (-7.15; 95% CI: -11.54 to -3.01) with retinal arteriolar caliber were significant and of similar magnitude (difference in effect, P=0.61), after adjusting for age, sex, maternal smoking, mean arterial blood pressure, and other confounders. These associations remained within dizygotic and monozygotic pairs. Analyses of head circumference and retinal arteriolar caliber were similar to those of birth length (within-pair regression coefficient: -2.41; 95% CI: -5.09 to 0.28; between-pair regression coefficient: -2.60; 95% CI: -5.00 to -0.19). For birth weight, only a between-pair association was evident (-7.28; 95% CI: -13.07 to -1.48). This study demonstrates a consistent association between smaller birth size and narrower retinal arterioles in twins. The independent effect of shorter birth length on retinal arteriolar caliber supports a role for twin-specific supply line factors affecting fetal growth on vascular structure.

  20. Fractal and multifractal analysis of human retinal vascular network: a review

    Directory of Open Access Journals (Sweden)

    Ştefan Ţălu

    2011-12-01

    Full Text Available The objective of this paper is to present a synthesis concerning the results obtained in fractaland multifractal analysis of vascular network geometry of the human retina. The numerical results areuseful in mathematical models based on parametric representations, used in vitreo-retinal biomechanicalstudies. The fractal and multifractal analysis of retinal vascular network provides noninvasive powerfultools that allow physicians the early detection of patients with different retinal vascular diseases.

  1. Hemoglobin is associated with retinal vascular fractals in type 1 diabetes patients

    DEFF Research Database (Denmark)

    Nybo, Mads; Hodgson, Lauren A B; Kawasaki, Ryo

    2014-01-01

    Software - Fractal (IRIS-Fractal). Df was calculated from a disc-centered retinal photo from the right eye. Hemoglobin concentrations were measured using routine equipment. RESULTS: Of 175 patients with gradable images, median age was 57.7 years and median duration of diabetes was 42 years. Median retinal...... concentration would be associated with retinal vascular fractals in a relevant population. METHODS: In a cross-sectional study of 204 long-term type 1 diabetes patients from a population-based cohort, retinal digital photos were captured and graded for fractal dimension (Df) by International Retinal Imaging.......01) and age (coefficient -0.0046 for each 10-year increase in age, p = 0.04). CONCLUSION: Hemoglobin correlated independently with retinal vascular fractals indicating a relationship between hemoglobin availability and retinal vascular structure....

  2. Increased vascular density and vitreo-retinal membranes accompany vascularization of the pigment epithelium in the dystrophic rat retina.

    Science.gov (United States)

    Caldwell, R B; Roque, R S; Solomon, S W

    1989-09-01

    Observations of vascularization of the retinal pigment epithelium (RPE) and formation of vitreo-retinal membranes (VRMs) in Royal College of Surgeons (RCS) rats with inherited retinal dystrophy suggest that vascular proliferation occurs in this model. To test this hypothesis, we studied the progression of vascular changes in RCS and age-matched control rats using quantitative light microscope morphometry and electron microscopy. At 2 weeks, prior to photoreceptor degeneration, the dystrophic retina is comparable with the control. By 2 months, extensive degeneration of photoreceptor cells results in significant thinning of the dystrophic retina as compared with the control. Signs of vascular degeneration are evident at the electron microscope level--"ghost" vessels consisting of acellular basal lamina surrounded by amorphous electron-dense material; degenerating endothelial cells and pericytes; and abnormal deposits of extracellular matrix (ECM) material around blood vessels. Vascular degeneration is accompanied by glial changes in the form of necrotic perivascular glial processes and abnormal ECM deposits among the altered Muller cell processes. At 2-4 months in the dystrophic retina, numbers of vessel profiles in dystrophic retinas are decreased as compared with controls. However, vascular degeneration is overshadowed by the formation of numerous capillary tufts within the RPE layer, which together with retinal thinning results in increased vessel density. Between 4-12 months, the retinal thickness diminishes further, vascularization of the RPE increases, vitreo-retinal membranes are formed, and vascular density increases. In summary, following an initial period of vascular degeneration, vascularization of the RPE is accompanied by an increase in retinal vessel density and by the formation of vitreo-retinal membranes.

  3. Astrocyte-derived vascular endothelial growth factor stabilizes vessels in the developing retinal vasculature.

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    Andrew Scott

    Full Text Available Vascular endothelial growth factor (VEGF plays a critical role in normal development as well as retinal vasculature disease. During retinal vascularization, VEGF is most strongly expressed by not yet vascularized retinal astrocytes, but also by retinal astrocytes within the developing vascular plexus, suggesting a role for retinal astrocyte-derived VEGF in angiogenesis and vessel network maturation. To test the role of astrocyte-derived VEGF, we used Cre-lox technology in mice to delete VEGF in retinal astrocytes during development. Surprisingly, this only had a minor impact on retinal vasculature development, with only small decreases in plexus spreading, endothelial cell proliferation and survival observed. In contrast, astrocyte VEGF deletion had more pronounced effects on hyperoxia-induced vaso-obliteration and led to the regression of smooth muscle cell-coated radial arteries and veins, which are usually resistant to the vessel-collapsing effects of hyperoxia. These results suggest that VEGF production from retinal astrocytes is relatively dispensable during development, but performs vessel stabilizing functions in the retinal vasculature and might be relevant for retinopathy of prematurity in humans.

  4. Correlation between penile cavernosal artery blood flow and retinal vascular findings in arteriogenic erectile dysfunction

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    Ahmed M Emarah

    2010-09-01

    Full Text Available Ahmed M Emarah1, Shawky M El-Haggar2, Ihab A Osman2, Abdel Wahab S Khafagy21Departments of Ophthalmology, 2Andrology and Sexology, Cairo University Hospital, EgyptObjectives: Arteriogenic erectile dysfunction (ED is a target organ disease of atherosclerosis, and therefore might be a predictor of systemic atherosclerosis. Being systemic, it might be possible to evaluate the extent of atherosclerosis from retinal vascular findings. We investigated the possible correlation between penile cavernosal artery blood flow and retinal vascular findings in patients with arteriogenic ED.Patients and methods: Sixty patients with ED were divided according to the peak systolic velocity (PSV in their penile cavernosal arteries into two groups; Group A included 30 patients with PSV less than 25 cm/sec, and Group B included 30 patients with PSV more than 35 cm/sec. Blood flow in the penile cavernosal artery was measured with color Doppler ultrasonography. All patients were assessed by ocular fundus examination under amydriatic conditions to evaluate retinal vascular atherosclerotic changes using Hyman’s classification.Results: Evidence of retinal vascular atherosclerotic changes was found in 19 patients (63.3% in Group A and in 10 patients (33.3% in Group B.Conclusions: Our study confirms the possibility of predicting penile arterial vascular status in patients with ED from their retinal vascular findings by using amydriatic simple, practical funduscopy.Keywords: erectile dysfunction, atherosclerosis, retinal vascular atherosclerosis

  5. [Retinal vascular changes--predictive and prognostic factor in systemic disease].

    Science.gov (United States)

    Vicol, Anca Delia; Bogdănici, Tudor; Bogdănici, Camelia

    2014-01-01

    The retinal circulation represents a unique window for the direct, non invazive in vivo status of the systemic mycrocirculation, but it can also offer scientific support for theories related strictly to ocular diseases, such as glaucoma (vascular theory). The interaction between intraocular pressure, retinal vessels and cerebrospinal fluid pressure located at the retrolaminar part of the optic nerve has been of great interest for both ophthalmologists or neuroscientists, both clinicians and researchers. The retinal vascular bed has structural and functional similarities with other vascular teritories such as Central Nervous System (CNS), kidneys and heart, so as for the ophthalmologist any vascular change in the retina can signalize a systemic disease (diabetes mellitus, stroke, arterial hypertension) that is more or less symptomatic for the patient. The purpose of this meta-analysis was to reviview recent literature data related to the connections between different hemodynamic structures and their impact on the retinal blood flow.

  6. Ethyl Pyruvate Prevents Methyglyoxal-Induced Retinal Vascular Injury in Rats

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    Junghyun Kim

    2013-01-01

    Full Text Available Pyruvate is an endogenous antioxidant substance. The aim of this study was to investigate the protective effects of ethyl pyruvate (EP on retinal vascular injury in diabetic retinopathy. To investigate the protective effect of EP on vascular cell apoptosis and blood-retinal barrier (BRB breakage, we have used intravitreally methylglyoxal-(MGO- injected rat eyes. Apoptosis of the retinal vascular cell that was stimulated by the intravitreal injection of MGO was evidently attenuated by the EP treatment. EP exerts inhibitory effect on MGO-induced vascular cell apoptosis by blocking oxidative injury. In addition, EP treatment prevented MGO-induced BRB breakage and the degradation of occludin, an important tight junction protein. These observations suggest that EP acts through an antioxidant mechanism to protect against oxidative stress-induced apoptosis in retinal vessels.

  7. Sac-0601 prevents retinal vascular leakage in a mouse model of diabetic retinopathy.

    Science.gov (United States)

    Maharjan, Sony; Lee, Sujin; Agrawal, Vijayendra; Choi, Hyun-Jung; Maeng, Yong-Sun; Kim, Kyeojin; Kim, Nam-Jung; Suh, Young-Ger; Kwon, Young-Guen

    2011-04-25

    Endothelium integrity is important for the normal functioning of vessels, the disruption of which can lead to disease. The blood-retinal barrier required for normal retinal function is compromised in diabetic retinopathy, causing retinal vascular leakage. Previously, we demonstrated the ability of Sac-0601[((2R,3S)-3-acetoxy-6-((3S,10R,13R,17R)-10,13-dimethyl-17-((R)-6-methylheptan-2-yl)-2,3,4,7,8,9,10,11,12,13,14,15,16,17-tetradecahydro-1H-cyclopenta[a]phenanthren-3-yloxy)-3,6-dihydro-2H-pyran-2-yl)methyl acetate], a pseudo-sugar derivative of cholesterol, to increase survival of retinal endothelial cells. In the present study, we evaluated the ability of Sac-0601 to prevent retinal vascular leakages in vitro and in vivo. Sac-0601 treatment blocked VEGF-induced formation of actin stress fibers and stabilized the cortical actin ring in retinal endothelial cells. It also inhibited degradation of occludin, an important tight junction protein, and blocked VEGF-induced disruption of its linear pattern at the cell border. The [(14)C] sucrose permeability assay demonstrated that Sac-0601 was able to prevent VEGF-induced retinal endothelial permeability. The compound inhibited the vascular leakage in retina of mice intravitreally injected with VEGF. And it also significantly reduced the leakage in retina of diabetic retinopathy mice model. Taken together, our findings suggest the potential therapeutic usefulness of Sac-0601 for retinal vascular permeability diseases.

  8. Retinal vascular caliber is associated with cardiovascular biomarkers of oxidative stress and inflammation: the POLA study.

    Directory of Open Access Journals (Sweden)

    Vincent Daien

    Full Text Available PURPOSE: Retinal vascular caliber has been linked with increased cardiovascular risk and is predictive of cardiovascular pathology, including stroke and coronary heart disease. Oxidative stress, as well as inflammatory mechanisms, plays a major role in the pathogenesis and progression of atherosclerosis, plaque rupture and vascular thrombotic propensity. The purpose of this study is to explore the relationship between retinal vascular calibers and biomarkers of oxidative stress and inflammation, in subjects free of cardiovascular pathology. PATIENTS AND METHODS: Cross-sectional analysis from a community-dwelling cohort comprising 1224 individuals aged 60 years and over, without a history of coronary or peripheral artery disease or stroke. Retinal vascular caliber was measured from fundus photographs using semi-automated standardized imaging software. Oxidative stress was evaluated using plasma superoxide dismutase 2 and glutathione peroxidase (GPx-3 activities, and inflammatory state was assessed using plasma high sensitivity C-reactive protein (hsCRP and orosomucoid. RESULTS: In a multivariate model controlling for cardiovascular risk factors, larger retinal arteriolar caliber was independently related to higher level of GPx-3 activity (p = 0.003 whereas larger venular caliber was associated with higher levels of hsCRP (p = 0.0001 and orosomucoid (p = 0.01. CONCLUSION: In the present study, biomarkers of oxidative stress regulation and inflammation were independently associated with retinal vascular calibers. This suggests that an assessment of retinal vessels may offer early and non-invasive detection of subclinical vascular pathology.

  9. Retinal vascular lesions in patients of Caucasian and Asian origin with type 2 diabetes - Baseline results from the ADVANCE Retinal Measurements (AdRem) study

    NARCIS (Netherlands)

    Stolk, Ronald P.; van Schooneveld, Mary J.; Cruickshank, J. Kennedy; Hughes, Alun D.; Stanton, Alice; Lu, Juming; Patel, Anushka; Thom, Simon A. McG.; Grobbee, Diederick E.; Vingerling, Johannes R.

    2008-01-01

    OBJECTIVE - The objective of this study was to describe prevalent vascular retinal lesions among patients with type 2 diabetes enrolled in the ADVANCE Retinal Measurements (AdRem) study, a substudy of the Action in Diabetes and Vascular Disease: Preterax and Diamicron MR Controlled Evaluation (ADVAN

  10. The development of blood-retinal barrier during the interaction of astrocytes with vascular wall cells

    Institute of Scientific and Technical Information of China (English)

    Huanling Yao; Tianshi Wang; Jiexin Deng; Ding Liu; Xiaofei Li; Jinbo Deng

    2014-01-01

    Astrocytes are intimately involved in the formation and development of retinal vessels. Astrocyte dysfunction is a major cause of blood-retinal barrier injury and other retinal vascular diseases. In this study, the development of the retinal vascular system and the formation of the blood-ret-inal barrier in mice were investigated using immunolfuorescence staining, gelatin-ink perfusion, and transmission electron microscopy. The results showed that the retinal vascular system of mice develops from the optic disc after birth, and radiates out gradually to cover the entire retina, taking the papilla optica as the center. First, the superifcial vasculature is formed on the inner retinal layer;then, the vasculature extends into the inner and outer edges of the retinal inner nuclear layer, forming the deep vasculature that is parallel to the superifcial vasculature. The blood-retinal barrier is mainly composed of endothelium, basal lamina and the end-feet of astrocytes, which become mature during mouse development. Initially, the naive endothelial cells were immature with few organelles and many microvilli. The basal lamina was uniform in thickness, and the glial end-feet surrounded the outer basal lamina incompletely. In the end, the blood-retinal barrier matures with smooth endothelia connected through tight junctions, rela-tively thin and even basal lamina, and relatively thin glial cell end-feet. These ifndings indicate that the development of the vasculature in the retina follows the rules of“center to periphery”and“superifcial layer to deep layers”. Its development and maturation are spatially and tempo-rally consistent with the functional performance of retinal neurons and photosensitivity. The blood-retinal barrier gradually becomes mature via the process of interactions between astro-cytes and blood vessel cells.

  11. Retinal vascular calibres are significantly associated with cardiovascular risk factors

    DEFF Research Database (Denmark)

    von Hanno, T.; Bertelsen, G.; Sjølie, Anne K.;

    2014-01-01

    ) and retinal venular calibre (central retinal vein equivalent) were measured computer-assisted on retinal photographs. Data on blood pressure, body mass index (BMI), high-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterol, glycosylated haemoglobin (HbA1c) and smoking were collected...... only. Blood pressure had the strongest effect on arteriolar calibre, with a decrease in calibre of 3.6m (women)/4.1m (men) per standard deviation increase in mean arterial blood pressure. Retinal venular calibre was independently associated with age, blood pressure, BMI, HDL and LDL cholesterol....... Association between retinal vessel calibre and the cardiovascular risk factors was assessed by multivariable linear and logistic regression analyses. Results: Retinal arteriolar calibre was independently associated with age, blood pressure, HbA1c and smoking in women and men, and with HDL cholesterol in men...

  12. Influence of cataract surgery and blood pressure changes caused by sodium restriction on retinal vascular diameter

    Directory of Open Access Journals (Sweden)

    Takatoshi Tano

    2010-11-01

    Full Text Available Takatoshi Tano1, Yoshimune Hiratsuka2, Koichi Ono1, Akira Murakami11Department of Ophthalmology, Juntendo University School of Medicine, Tokyo; 2National Institute of Public Health, Tokyo, JapanPurpose: To investigate the impact of cataract surgery and blood pressure changes induced by one week of sodium restriction on retinal vascular diameter.Methods: Fundus photographs of 200 patients were obtained before and one week after cataract surgery. For one week after admission, 100 patients received sodium restriction and 100 patients (ie, the control group did not receive sodium restriction. The diameter of the retinal vessels and blood pressure were compared between the sodium restriction group and the control group. The vascular diameter was measured using an objective computer-based method.Results: Neither group had a significant change in the diameter of the retinal vessels after cataract surgery. Although there was no significant change in retinal arterial and venular diameter in the sodium restriction group, one-week sodium restriction significantly reduced mean blood pressure. However, multiple linear regression analyses indicated that an increase in retinal arteriolar diameter was significantly associated with diabetes, hyperlipidemia, and alcohol intake.Conclusion: Cataract surgery and blood pressure reduction induced by one week of sodium restriction resulted in no significant change in retinal arteriolar diameter.Keywords: cataract surgery, hypertension, retinal blood vessel diameter, retinal fundus camera, sodium restriction.

  13. Retinal vascular geometry and its association to microvascular complications in patients with type 1 diabetes

    DEFF Research Database (Denmark)

    Rasmussen, M L; Broe, R; Frydkjaer-Olsen, U

    2017-01-01

    of patients with T1DM participated in a clinical examination in 2011. Blood and urine analyses were done and retinal images taken. PDR was defined as Early Treatment Diabetic Retinopathy Study level 61 or above, nephropathy as albumin-creatinin ratio ≥300 mg/g, and neuropathy as vibration perception threshold......PURPOSE: To examine associations between retinal vascular geometry (tortuosity, branching coefficient [BC] and length-diameter ratio [LDR]) and diabetic proliferative retinopathy (PDR), nephropathy, and peripheral neuropathy in patients with type 1 diabetes mellitus (T1DM). METHODS: A cohort...... >25 Volt. Retinal vessel parameters were measured using semi-automated software. Multiple logistic regressions were performed to investigate correlations between retinal vascular parameters and outcomes. Models were adjusted for other variables (sex, age, duration of diabetes, systolic and diastolic...

  14. Oral contraceptive pills: A risk factor for retinal vascular occlusion in in-vitro fertilization patients

    Directory of Open Access Journals (Sweden)

    Rohina S Aggarwal

    2013-01-01

    Full Text Available Retinal vascular occlusion is the most common cause of retinopathy leading to severe visual loss in all age groups. Central retinal vein occlusion (CRVO is usually seen in older age group and is often associated with systemic vascular diseases. Although the exact cause and effect relationship has not been proven, central retinal vein occlusion has been associated with various systemic pathological conditions, hence a direct review of systems toward the various systemic and local factors predisposing the central retinal vein occlusion is advocated. We describe the development of central retinal venous occlusion with associated cystoid macular edema (CME in two healthy infertile women who were recruited for in vitro fertilization cycle for infertility. Predisposing risk factors associated with central retinal vein occlusion are obesity, sedentary life style, smoking, and some systemic diseases such as hyperlipidemia, hypertension, associated autoimmune disorders e.g., antiphospholipid antibody syndrome, lupus, diabetes mellitus, cardiovascular disorders, bleeding or clotting disorders, vasculitis, closed-head trauma, alcohol consumption, primary open-angle glaucoma or angle-closure glaucoma.In our patients, they were ruled out afterdoing allpertaining investigations. The cases were managed with further avoidance of oral contraceptives and intra-vitreal injections of Bevacizumab (Avastin, an anti-vascular endothelial growth factor (anti-VEGF drug and Triamcinolone acetonide (a long acting synthetic steroid. Hence, even if no systemic diseases are detected. Physical examinations are recommended periodically for young women on oral contraceptive pills.

  15. Retinal vascular changes in hypertensive patients in Ibadan, Sub-Saharan Africa

    Directory of Open Access Journals (Sweden)

    Oluleye ST

    2016-08-01

    Full Text Available Sunday Tunji Oluleye,1 Bolutife Ayokunu Olusanya,1 Abiodun Moshood Adeoye2 1Department of Ophthalmology, 2Department of Medicine, College of Medicine, University of Ibadan and University College Hospital, Ibadan, Nigeria Background: Earlier studies in Nigeria reported the rarity of retinal vascular changes in hypertensives. The aim of this study was to describe the various retinal vascular changes in the hypertensive patients of Nigeria.Patients and methods: Nine hundred and three hypertensive patients were studied. This study was approved by the ethical and research committee of the University of Ibadan and University College Hospital, Ibadan, Nigeria. Blood pressure and anthropometric measurements were measured. Cardiac echocardiography was performed on 156 patients. All patients had dilated fundoscopy and fundus photography using the Kowa portable fundus camera and an Apple iPhone with 20 D lens. Statistical analysis was done with Statistical Packages for the Social Sciences (Version 21.Results: The mean age of patients was 57 years with a male:female ratio of 1. No retinopathy was found in 556 (61.5% patients. In all, 175 (19.4% patients had features of hypertensive retinopathy. Retinal vascular occlusion was a significant finding in 121 patients (13.4%, of which branch retinal vein occlusion, 43 (4.7%, and central retinal vein occlusion, 30 (3.3%, were the most prominent ones in cases. Hemicentral retinal vein occlusion, 26 (2.9%, and central retinal artery occlusion, 17 (1.9%, were significant presentations. Other findings included nonarteritic anterior ischemic optic neuropathy in five (0.6% patients, hypertensive choroidopathy in seven (0.8% patients, and hemorrhagic choroidal detachment in five (0.6% patients. Left ventricular (LV geometry was abnormal in 85 (55.5% patients. Concentric remodeling, eccentric hypertrophy, and concentric hypertrophy were observed in 43 (27.6%, 26 (17.2%, and 15 (9.7% patients, respectively. LV

  16. RNA interference inhibits expression of vascular endothelial growth factor (VEGF) in human retinal pigment epithelial cells

    Institute of Scientific and Technical Information of China (English)

    CAI Chun-mei; SUN Bao-chen; LIU Xu-yang; WANG Jin-jin; LI Jun-fa; HAN Song; WANG Ning-li; LU Qing-jun

    2005-01-01

    @@ Choroidal neovascularization (CNV), a major cause of vision loss, is the result of the increased vascular endothelial growth factor (VEGF) expression in human retinal pigment epithelial (RPE) cells. It is important to inhibit the expression of VEGF protein in RPE cells.

  17. Assessing the Causality between Blood Pressure and Retinal Vascular Caliber through Mendelian Randomisation

    Science.gov (United States)

    Li, Ling-Jun; Liao, Jiemin; Cheung, Carol Yim-Lui; Ikram, M. Kamran; Shyong, Tai E.; Wong, Tien-Yin; Cheng, Ching-Yu

    2016-02-01

    We aimed to determine the association between blood pressure (BP) and retinal vascular caliber changes that were free from confounders and reverse causation by using Mendelian randomisation. A total of 6528 participants from a multi-ethnic cohort (Chinese, Malays, and Indians) in Singapore were included in this study. Retinal arteriolar and venular caliber was measured by a semi-automated computer program. Genotyping was done using Illumina 610-quad chips. Meta-analysis of association between BP, and retinal arteriolar and venular caliber across three ethnic groups was performed both in conventional linear regression and Mendelian randomisation framework with a genetic risk score of BP as an instrumental variable. In multiple linear regression models, each 10 mm Hg increase in systolic BP, diastolic BP, and mean arterial BP (MAP) was associated with significant decreases in retinal arteriolar caliber of a 1.4, 3.0, and 2.6 μm, and significant decreases in retinal venular caliber of a 0.6, 0.7, and 0.9 μm, respectively. In a Mendelian randomisation model, only associations between DBP and MAP and retinal arteriolar narrowing remained yet its significance was greatly reduced. Our data showed weak evidence of a causal relationship between elevated BP and retinal arteriolar narrowing.

  18. Retinal vascular calibre and response to light exposure and serial imaging

    DEFF Research Database (Denmark)

    von Hanno, T.; Sjølie, Anne K.; Mathiesen, E. B.

    2014-01-01

    and vein equivalents (CRAE and CRVE). Outcome measures were difference in calibres after prior light versus prior dark exposure and difference in calibre during each of the two imaging sequences. Results: CRVE was wider with prior light exposure (2.7%, p = 0.0001), comparing the first image in each image......Purpose: To investigate whether retinal vessel calibre measurements on optical retinal photography are affected by light and dark exposure prior to photography and whether the vessel calibre changes during an imaging sequence of several images. Methods: Digital optical retinal photographs were...... obtained from 32 healthy adults in two separate image sequences of six images during 1 min; one sequence with 10 min of dark exposure and one with 10 min of light exposure prior to imaging. Retinal arteriolar and venular calibres were measured computer-assisted and summarized as central retinal artery...

  19. Retinal Vascular Tortuosity in a Patient with Weill-Marchesani Syndrome

    Directory of Open Access Journals (Sweden)

    Kevin Gallagher

    2011-01-01

    Full Text Available Weill-Marchesani syndrome (WMS is a rare connective tissue disorder with characteristic phenotypic skeletal and ocular manifestations. A 28-year-old myopic female presented with an 8-month history of bilateral blurred vision. On examination, she was noted to be of short stature with brachydactyly. On ocular examination, she was found to be spherophakic with bilateral inferiorly subluxated lenses. Serum and urine homocysteine were normal and a syphilis screen was negative. A diagnosis of Weill-Marchesani syndrome was made. Fundoscopy revealed bilateral tortuous retinal vessels. We report the first illustrated case of retinal vascular tortuosity as an ocular manifestation of Weill-Marchesani syndrome.

  20. Retinal vascular changes in hypertensive patients in Ibadan, Sub-Saharan Africa

    Science.gov (United States)

    Oluleye, Sunday Tunji; Olusanya, Bolutife Ayokunu; Adeoye, Abiodun Moshood

    2016-01-01

    Background Earlier studies in Nigeria reported the rarity of retinal vascular changes in hypertensives. The aim of this study was to describe the various retinal vascular changes in the hypertensive patients of Nigeria. Patients and methods Nine hundred and three hypertensive patients were studied. This study was approved by the ethical and research committee of the University of Ibadan and University College Hospital, Ibadan, Nigeria. Blood pressure and anthropometric measurements were measured. Cardiac echocardiography was performed on 156 patients. All patients had dilated fundoscopy and fundus photography using the Kowa portable fundus camera and an Apple iPhone with 20 D lens. Statistical analysis was done with Statistical Packages for the Social Sciences (Version 21). Results The mean age of patients was 57 years with a male:female ratio of 1. No retinopathy was found in 556 (61.5%) patients. In all, 175 (19.4%) patients had features of hypertensive retinopathy. Retinal vascular occlusion was a significant finding in 121 patients (13.4%), of which branch retinal vein occlusion, 43 (4.7%), and central retinal vein occlusion, 30 (3.3%), were the most prominent ones in cases. Hemicentral retinal vein occlusion, 26 (2.9%), and central retinal artery occlusion, 17 (1.9%), were significant presentations. Other findings included nonarteritic anterior ischemic optic neuropathy in five (0.6%) patients, hypertensive choroidopathy in seven (0.8%) patients, and hemorrhagic choroidal detachment in five (0.6%) patients. Left ventricular (LV) geometry was abnormal in 85 (55.5%) patients. Concentric remodeling, eccentric hypertrophy, and concentric hypertrophy were observed in 43 (27.6%), 26 (17.2%), and 15 (9.7%) patients, respectively. LV hypertrophy was found in 42 (27%) patients, while 60 (39%) patients had increased relative wall thickness. In this study, bivariate analysis showed a correlation between LV relative wall thickness and severity of retinopathy in both eyes

  1. Association Between Retinal Vascular Calibre and Blindness in Young Patients With Type 1 Diabetes

    DEFF Research Database (Denmark)

    Rasmussen, Malin Lundberg

    Association Between Retinal Vascular Calibre and Blindness in Young Patients With Type 1 Diabetes Purpose To examine the association between retinal vascular calibre and incident blindness caused by diabetic retinopathy in young patients with type 1 diabetes. Methods A case-control study of 6...... patients (12 eyes) who later went blind and 18 age- and sex-matched controls (36 eyes). They were all identified in a population-based cohort study of 339 patients with type 1 diabetes. Patients and controls all participated in a clinical baseline examination in 1995 and were subsequently followed for 15...... years. Incident blindness was defined for patients who registered between 1995 and 2010 in the Danish Association of the Blind, which is a voluntary organization open for patients with a visual acuity at or below 6/60 (0.1) in the best eye. Each blind patient was matched with 3 controls regarding age...

  2. Experimental Branch Retinal Vein Occlusion Induces Upstream Pericyte Loss and Vascular Destabilization.

    Directory of Open Access Journals (Sweden)

    Elisa Dominguez

    Full Text Available Branch retinal vein occlusion (BRVO leads to extensive vascular remodeling and is important cause of visual impairment. Although the vascular morphological changes following experimental vein occlusion have been described in a variety of models using angiography, the underlying cellular events are ill defined.We here show that laser-induced experimental BRVO in mice leads to a wave of TUNEL-positive endothelial cell (EC apoptosis in the upstream vascular network associated with a transient edema and hemorrhages. Subsequently, we observe an induction of EC proliferation within the dilated vein and capillaries, detected by EdU incorporation, and the edema resolves. However, the pericytes of the upstream capillaries are severely reduced, which was associated with continuing EC apoptosis and proliferation. The vascular remodeling was associated with increased expression of TGFβ, TSP-1, but also FGF2 expression. Exposure of the experimental animals to hypoxia, when pericyte (PC dropout had occurred, led to a dramatic increase in endothelial cell proliferation, confirming the vascular instability induced by the experimental BRVO.Experimental BRVO leads to acute endothelial cells apoptosis and increased permeability. Subsequently the upstream vascular network remains destabilized, characterized by pericyte dropout, un-physiologically high endothelial cells turnover and sensitivity to hypoxia. These early changes might pave the way for capillary loss and subsequent chronic ischemia and edema that characterize the late stage disease.

  3. The Association of Type 2 Diabetes Mellitus with Cerebral Gray Matter Volume Is Independent of Retinal Vascular Architecture and Retinopathy

    Directory of Open Access Journals (Sweden)

    C. Moran

    2016-01-01

    Full Text Available It is uncertain whether small vessel disease underlies the relationship between Type 2 Diabetes Mellitus (T2DM and brain atrophy. We aimed to study whether retinal vascular architecture, as a proxy for cerebral small vessel disease, may modify or mediate the associations of T2DM with brain volumes. In this cross-sectional study using Magnetic Resonance Imaging (MRI scans and retinal photographs in 451 people with and without T2DM, we measured brain volumes, geometric measures of retinal vascular architecture, clinical retinopathy, and MRI cerebrovascular lesions. There were 270 people with (mean age 67.3 years and 181 without T2DM (mean age 72.9 years. T2DM was associated with lower gray matter volume (p=0.008. T2DM was associated with greater arteriolar diameter (p=0.03 and optimality ratio (p=0.04, but these associations were attenuated by adjustments for age and sex. Only optimality ratio was associated with lower gray matter volume (p=0.03. The inclusion of retinal measures in regression models did not attenuate the association of T2DM with gray matter volume. The association of T2DM with lower gray matter volume was independent of retinal vascular architecture and clinical retinopathy. Retinal vascular measures or retinopathy may not be sufficiently sensitive to confirm a microvascular basis for T2DM-related brain atrophy.

  4. Retinal hypoxia induces vascular endothelial growth factor through induction of estrogen-related receptor γ

    Energy Technology Data Exchange (ETDEWEB)

    Do, Ji Yeon; Choi, Young Keun [Leading-edge Research Center for Drug Discovery and Development for Diabetes and Metabolic Disease, Kyungpook National University School of Medicine, Kyungpook National University, Daegu (Korea, Republic of); Kook, Hyun [Department of Pharmacology, Chonnam National University Medical School, Gwangju (Korea, Republic of); Suk, Kyoungho [Department of Pharmacology, Brain Science & Engineering Institute, Kyungpook National University School of Medicine, Daegu (Korea, Republic of); Lee, In-Kyu [Leading-edge Research Center for Drug Discovery and Development for Diabetes and Metabolic Disease, Kyungpook National University School of Medicine, Kyungpook National University, Daegu (Korea, Republic of); Division of Endocrinology and Metabolism, Department of Internal Medicine, Research Institute of Aging and Metabolism, Kyungpook National University School of Medicine, Daegu (Korea, Republic of); Park, Dong Ho, E-mail: sarasate2222@gmail.com [Department of Ophthalmology, Kyungpook National University School of Medicine, Daegu (Korea, Republic of)

    2015-05-01

    Ischemic retinopathies causing overexpression of pro-angiogenic factors, including vascular endothelial growth factor (VEGF), are the most common cause of blindness. Thus, understanding the pathophysiology of targetable pathways that regulate retinal VEGF is of great interest. A conserved binding site for estrogen-related receptor γ (ERRγ) has been identified in the promoter of the Vegfa gene. ERRγ is a constitutively active orphan nuclear receptor and its expression is increased by hypoxic stimuli in metabolically active tissues. This study evaluated the role of ERRγ in the ischemic retina and the anti-VEGF potential of GSK5182, a selective inverse agonist of ERRγ. In an oxygen-induced retinopathy (OIR) mouse model, immunohistochemistry showed significantly increased ERRγ expression in the ganglion cell layer at postnatal day (P) 17. In a ganglion cell line (RGC-5), mRNA and protein levels of ERRγ were increased by desferrioxamine treatment and hypoxic conditions (1% O{sub 2}). Transient transfection of RGC-5 cells revealed that ERRγ regulated Vegfa expression and this was inhibited by GSK5182. Intravitreal injection of GSK5182 into the OIR model at P14 inhibited retinal Vegfa mRNA expression at P17. GSK5182 suppresses hypoxia-induced VEGF expression via ERRγ; therefore, ERRγ could be a treatment target for ischemic retinopathies. - Highlights: • OIR mice exhibited increased ERRγ expression in the ganglion cell layer. • Hypoxia-induced ERRγ expression was observed in retinal ganglion cells. • ERRγ overexpression increased VEGFA expression in retinal ganglion cells. • An ERRγ inverse agonist suppressed VEGFA expression in retinal ganglion cells. • Intravitreal injection of an ERRγ inverse agonist suppressed VEGFA in OIR mice.

  5. Small interference RNA targeting vascular endothelial growth factor gene effectively attenuates retinal neovascularization in mice model

    Institute of Scientific and Technical Information of China (English)

    KONG Yi-chun; SUN Bei; ZHAO Kan-xing; HAN Mei; WANG Yu-chuan

    2013-01-01

    Background The mechanism of retinal neovascularization is not understood completely.Many growth factors are involved in the process of retinal neovascularization,such as vascular endothelial growth factor (VEGF) and pigment epithelium-deprived factor (PEDF),which are the representatives of angiogenic and antiangiogenic molecules respectively.Oxygen induced retinopathy (OIR) is a useful model to investigate retinal neovascularization.The present study was conducted to investigate the feasibility of small interference RNA (siRNA) targeting VEGF gene in attenuating oxygen induced retinopathy (OIR) by regulating VEGF to PEDF ratio (VEGF/PEDF).Methods In vitro,cultured EOMA cells were transfected with VEGF-siRNA (psi-HITM/EGFPNEGF siRNA) and LipofectamineTM 2000 for 24,48,and 72 hours,respectively.Expression of VEGF mRNA was evaluated by real time polymerase chain reaction (PCR) and the level of VEGF protein was analyzed by Western blotting.In vivo,OIR model mice were established,the mice (C57BL/6J) received an intra-vitreal injection of 1 μl of mixture of psi-HITM/EGFPNEGF siRNA and Lipofectamine 2000.Expressions of retinal VEGF and PEDF protein were measured by Western blotting,retinal neovascularization was observed by fluorescein angiography,and quantified.Results In vitro psi-HITM/EGFP/VEGF siRNA treatment significantly reduced VEGF mRNA and protein expression.In vivo,with decreased VEGF and VEGF-PEDF ratio,significant attenuation of neovascular tufts,avascular regions,tortuous,and dilated blood vessels were observed in the interfered animals.Conclusions VEGF plays an important role in OIR,and the transfection of VEGF-siRNA can effectively downregulate VEGF expression in vivo,accompanied by the downregulation of VEGF-PEDF ratio,and simultaneous attenuation of retinal neovascularization was also observed.These findings suggest that VEGF/PEDF may serve as a potential target in the treatment of retinal neovascularization and RNA interference targeting VEGF expression

  6. Retinal vascular lesions in patients with type 2 diabetes mellitus of Caucasian and Asian origin - baseline results from the AdRem study

    NARCIS (Netherlands)

    Stolk, R.P.; van Schooneveld, M.J.; Cruickshank, J.K.; Hughes, A.D.; Stanton, A.; Lu, J.; Patel, A.; Thom, S.A.; Grobbee, D.E.; Vingerling, J.R.

    2008-01-01

    Objective: To describe prevalent vascular retinal lesions among patients with type 2 diabetes enrolled in the ADVANCE Retinal measurement study (AdRem), a sub-study of the Action in Diabetes and Vascular disease - Preterax and Diamicron Controlled Evaluation (ADVANCE) trial. Research Design and Meth

  7. Mutations in Lama1 disrupt retinal vascular development and inner limiting membrane formation.

    Science.gov (United States)

    Edwards, Malia M; Mammadova-Bach, Elmina; Alpy, Fabien; Klein, Annick; Hicks, Wanda L; Roux, Michel; Simon-Assmann, Patricia; Smith, Richard S; Orend, Gertraud; Wu, Jiang; Peachey, Neal S; Naggert, Jürgen K; Lefebvre, Olivier; Nishina, Patsy M

    2010-03-05

    The Neuromutagenesis Facility at the Jackson Laboratory generated a mouse model of retinal vasculopathy, nmf223, which is characterized clinically by vitreal fibroplasia and vessel tortuosity. nmf223 homozygotes also have reduced electroretinogram responses, which are coupled histologically with a thinning of the inner nuclear layer. The nmf223 locus was mapped to chromosome 17, and a missense mutation was identified in Lama1 that leads to the substitution of cysteine for a tyrosine at amino acid 265 of laminin alpha1, a basement membrane protein. Despite normal localization of laminin alpha1 and other components of the inner limiting membrane, a reduced integrity of this structure was suggested by ectopic cells and blood vessels within the vitreous. Immunohistochemical characterization of nmf223 homozygous retinas demonstrated the abnormal migration of retinal astrocytes into the vitreous along with the persistence of hyaloid vasculature. The Y265C mutation significantly reduced laminin N-terminal domain (LN) interactions in a bacterial two-hybrid system. Therefore, this mutation could affect interactions between laminin alpha1 and other laminin chains. To expand upon these findings, a Lama1 null mutant, Lama1(tm1.1Olf), was generated that exhibits a similar but more severe retinal phenotype than that seen in nmf223 homozygotes. The increased severity of the Lama1 null mutant phenotype is probably due to the complete loss of the inner limiting membrane in these mice. This first report of viable Lama1 mouse mutants emphasizes the importance of this gene in retinal development. The data presented herein suggest that hypomorphic mutations in human LAMA1 could lead to retinal disease.

  8. A novel measure to characterise optimality of diameter relationships at retinal vascular bifurcations.

    Science.gov (United States)

    Witt, Nicholas W; Chapman, Neil; Thom, Simon A McG; Stanton, Alice V; Parker, Kim H; Hughes, Alun D

    2010-09-01

    Conventionally, the relationship between parent and daughter vessels at vascular bifurcations has been expressed by the junction exponent (x), and deviations of this parameter from the optimal conditions predicted by Murray's law (x = 3) have been shown to be associated with vascular disease. However, the junction exponent is normally calculated iteratively from diameter measurements, and Monte-Carlo simulation studies show the junction exponent to be biased in the presence of measurement noise.We present an alternative parameter, referred to as optimality ratio, that is simpler to compute and also more robust in the presence of noise.To demonstrate the sensitivity of the optimality ratio to alterations in topography of the retinal vascular network, we analysed the effect of inducing endothelial dysfunction by infusion of NG-monomethyl-l-arginine (l-NMMA), a nitric oxide synthase inhibitor, compared to placebo in a double-blind crossover study. The optimality ratio showed a significant increase (p = 0.03) during infusion of l-NMMA compared to placebo.We propose that a measure of the extent of departure of optimality ratio from its optimal value of 2(-1/3) may be a useful indicator of microvascular endothelial dysfunction in vivo.

  9. Bone morphogenetic protein-4 enhances vascular endothelial growth factor secretion by human retinal pigment epithelial cells.

    Science.gov (United States)

    Vogt, Rhonda R; Unda, Richard; Yeh, Lee-Chuan C; Vidro, Eileen K; Lee, John C; Tsin, Andrew T

    2006-08-01

    Retinal pigment epithelial (RPE) cells secrete vascular endothelial growth factor (VEGF), a cytokine known to promote angiogenesis. Results from RNase protection assays (RPAs) show that RPE from non-diabetic human donors and from adult retinal pigment epithelium-19 (ARPE-19) cells expressed significant bone morphogenetic protein-4 (BMP-4) message. In addition, ARPE-19 cells cultured in high glucose (25 mM), compared to those in physiological glucose (5.5 mM) released significantly more BMP-4 into the conditioned media (CM). However, the effect of BMP-4 on the release of VEGF by ARPE-19 cells has not been studied. Accordingly, ARPE-19 cells were treated with BMP-4 to determine VEGF secretion. BMP-4 and VEGF levels in the CM and cell lysates were measured by enzyme-linked immunosorbent assay (ELISA). Cells treated with exogenous BMP-4 had higher VEGF in the CM and this treatment effect was dose- and time-dependent, while cell lysates had low levels of VEGF. Addition of cycloheximide (CHX) or actinomycin-D (ACT) significantly reduced VEGF secretion from cells treated with BMP-4, suggesting that the BMP-4-induced secretion of VEGF requires new RNA and protein synthesis. Our results suggest that BMP-4 may play a role in the regulation of ocular angiogenesis associated with diabetic retinopathy (DR) by stimulating VEGF release from RPE cells.

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

    Science.gov (United States)

    Schaller, G; Kolodjaschna, J; Pleiner, J; Mittermayer, F; Kapiotis, S; Schmetterer, L; Wolzt, M

    2008-08-01

    PPARgamma agonists have been proposed to exert more than metabolic benefits, particularly by anti-inflammatory mechanisms. We hypothesized that pioglitazone might modulate inflammatory and vascular responses to lipopolysaccharide (LPS). In a placebo-controlled parallel-group study in 18 healthy male subjects, the E. coli endotoxin model of inflammation (20 IU/kg i. v.) was employed to test the effect of 60 mg pioglitazone over nine days on inflammatory cytokines. Macrovascular function and microvascular blood flow were assessed by brachial artery ultrasound and retinal blood flow parameters, respectively. Pioglitazone increased brachial artery diameter by 5.6% but had no effect on other outcome parameters under resting conditions. LPS increased cytokine levels to peak concentrations of 91.3+/-22.5 ng/ml (IL-6), 261.4+/-60.0 ng/ml (TNFalpha), and 524.5+/-15.3 ng/ml (VCAM-1). The endotoxin caused microvascular vasodilation and increased retinal white blood cell flux, while baseline brachial artery diameter remained unchanged. Pioglitazone had no effect on inflammatory cytokine or adhesion molecule release but mitigated LPS-induced hypotension (p<0.05). Neither brachial artery function nor microvascular blood flow was altered by pioglitazone. In conclusion, acute immune reactions to LPS are not affected by pioglitazone, which exerts subtle vascular effects alone and during endotoxemia. The anti-inflammatory properties of short-term pioglitazone to endotoxins in healthy subjects are therefore limited.

  11. Elk3 deficiency causes transient impairment in post-natal retinal vascular development and formation of tortuous arteries in adult murine retinae.

    Directory of Open Access Journals (Sweden)

    Christine Weinl

    Full Text Available Serum Response Factor (SRF fulfills essential roles in post-natal retinal angiogenesis and adult neovascularization. These functions have been attributed to the recruitment by SRF of the cofactors Myocardin-Related Transcription Factors MRTF-A and -B, but not the Ternary Complex Factors (TCFs Elk1 and Elk4. The role of the third TCF, Elk3, remained unknown. We generated a new Elk3 knockout mouse line and showed that Elk3 had specific, non-redundant functions in the retinal vasculature. In Elk3(-/- mice, post-natal retinal angiogenesis was transiently delayed until P8, after which it proceeded normally. Interestingly, tortuous arteries developed in Elk3(-/- mice from the age of four weeks, and persisted into late adulthood. Tortuous vessels have been observed in human pathologies, e.g. in ROP and FEVR. These human disorders were linked to altered activities of vascular endothelial growth factor (VEGF in the affected eyes. However, in Elk3(-/- mice, we did not observe any changes in VEGF or several other potential confounding factors, including mural cell coverage and blood pressure. Instead, concurrent with the post-natal transient delay of radial outgrowth and the formation of adult tortuous arteries, Elk3-dependent effects on the expression of Angiopoietin/Tie-signalling components were observed. Moreover, in vitro microvessel sprouting and microtube formation from P10 and adult aortic ring explants were reduced. Collectively, these results indicate that Elk3 has distinct roles in maintaining retinal artery integrity. The Elk3 knockout mouse is presented as a new animal model to study retinal artery tortuousity in mice and human patients.

  12. Diosmin alleviates retinal edema by protecting the blood-retinal barrier and reducing retinal vascular permeability during ischemia/reperfusion injury.

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    Nianting Tong

    Full Text Available BACKGROUND AND PURPOSE: Retinal swelling, leading to irreversible visual impairment, is an important early complication in retinal ischemia/reperfusion (I/R injury. Diosmin, a naturally occurring flavonoid glycoside, has been shown to have antioxidative and anti-inflammatory effects against I/R injury. The present study was performed to evaluate the retinal microvascular protective effect of diosmin in a model of I/R injury. METHODS: Unilateral retinal I/R was induced by increasing intraocular pressure to 110 mm Hg for 60 min followed by reperfusion. Diosmin (100 mg/kg or vehicle solution was administered intragastrically 30 min before the onset of ischemia and then daily after I/R injury until the animals were sacrificed. Rats were evaluated for retinal functional injury by electroretinogram (ERG just before sacrifice. Retinas were harvested for HE staining, immunohistochemistry assay, ELISA, and western blotting analysis. Evans blue (EB extravasation was determined to assess blood-retinal barrier (BRB disruption and the structure of tight junctions (TJ was examined by transmission electron microscopy. RESULTS: Diosmin significantly ameliorated the reduction of b-wave, a-wave, and b/a ratio in ERG, alleviated retinal edema, protected the TJ structure, and reduced EB extravasation. All of these effects of diosmin were associated with increased zonular occluden-1 (ZO-1 and occludin protein expression and decreased VEGF/PEDF ratio. CONCLUSIONS: Maintenance of TJ integrity and reduced permeability of capillaries as well as improvements in retinal edema were observed with diosmin treatment, which may contribute to preservation of retinal function. This protective effect of diosmin may be at least partly attributed to its ability to regulate the VEGF/PEDF ratio.

  13. Retinal occlusive vasculer disorder and rheumatoid arthritis

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    Huseyin Ortak

    2013-03-01

    Full Text Available Rheumatoid arthritis is a systemic inflammatory disease that affected older women with many ocular manifestations. Also, these systemic diseases can cause retinal vein occlusion and arterial occlusion that lead to serious and permanent visual loss. Rheumatoid arthritis's the most common manifestation is that retinal vasculitis and retinal vascular complications are associated with this complication. In this review, retinal vascular occlusive diseases are presented to associated with rheumatoid arthritis in literature. Rheumatoid arthritis and its complications have been outlined and was made to create a new perspective. [J Contemp Med 2013; 3(1.000: 71-73

  14. Anti-Vascular Endothelial Growth Factor Agents in the Treatment of Retinal Disease: From Bench to Bedside.

    Science.gov (United States)

    Campochiaro, Peter A; Aiello, Lloyd Paul; Rosenfeld, Philip J

    2016-10-01

    The association of retinal hypoxia with retinal neovascularization has been recognized for decades, causing Michaelson to postulate in 1948 that a factor secreted by hypoxic retina was involved. The isolation of vascular endothelial growth factor (VEGF), characterization of its angiogenic activity, and demonstration that its expression was increased in hypoxic tissue made it a prime candidate. Intraocular levels of VEGF are elevated in patients with retinal or iris neovascularization, and VEGF-specific antagonists markedly suppress retinal neovascularization in mice and primates with ischemic retinopathy. Vascular endothelial growth factor antagonists also suppress choroidal neovascularization, and transgenic expression of VEGF in the retina of mice causes subretinal neovascularization. Clinical trials using a VEGF antagonist that blocks all isoforms of VEGF-A in patients with neovascular age-related macular degeneration (nAMD) demonstrated dramatic benefit. Similar results have been obtained with 2 other VEGF antagonists. Retinal hypoxia also contributes to diabetic macular edema (DME), and because of the absence of good animal models, small clinical trials were used to test the role of VEGF. The results clearly implicated VEGF as a major contributor to DME and have been confirmed by several large multicenter trials. A similar strategy demonstrated that VEGF is a major contributor to macular edema resulting from retinal vein occlusion, also confirmed in multicenter trials. Secondary outcomes in these large clinical trials have shown that VEGF inhibition improves retinal hemorrhages, retinal vessel closure, and progression of nonproliferative diabetic retinopathy. Anti-VEGF agents also provide therapeutic benefits in proliferative diabetic retinopathy. Thus, the development of VEGF antagonists has revolutionized the treatment of nAMD, diabetic retinopathy, and other ischemic retinopathies, but in many patients, the upregulation of VEGF is prolonged. Although the

  15. Relationship between Retinal Vascular Caliber and Coronary Artery Disease in Patients with Non-Alcoholic Fatty Liver Disease (NAFLD

    Directory of Open Access Journals (Sweden)

    Marmor Alon

    2013-08-01

    Full Text Available Objective: To evaluate the relationship between retinal vascular caliber and cardiovascular disease in non-alcoholic fatty liver disease (NAFLD patients without diabetes and hypertension. Methods: Intention to treat study of individuals who underwent cardiac computed tomography (CT during a two year period. Coronary artery disease (CAD was defined as stenosis of >50% in at least one major coronary artery. Liver and spleen density were measured by abdominal (CT; intima-media thickness (IMT by Doppler ultrasound; retinal artery and vein diameter by colored-retinal angiography; and metabolic syndrome by ATP III guidelines. Serum biomarkers of insulin resistance, inflammation, and oxidant-antioxidant status were assessed. Results: Compared with 22 gender and age matched controls, the 29 NAFLD patients showed higher prevalence of coronary plaques (70% vs. 30%, p < 0.001, higher prevalence of coronary stenosis (30% vs. 15%, p < 0.001, lower retinal arteriole-to-venule ratio (AVR (0.66 ± 0.06 vs. 0.71 ± 0.02, p < 0.01, higher IMT (0.98 ± 0.3 vs. 0.83 ± 0.1, p < 0.04, higher carotid plaques (60% vs. 40%, p < 0.001, higher homeostasis model assessment of insulin resistance (HOMA (4.0 ± 3.4 vs. 2.0 ± 1.0, p < 0.005, and higher triglyceride levels (200 ± 80 vs. 150 ± 60, p < 0.005 than controls. Multivariate analysis showed fatty liver (OR 2.5; p < 0.01, IMT (OR 2.3 p < 0.001, and retinal AVR ratio (OR 1.5, p < 0.01 to be strongly associated with CAD independent of metabolic syndrome (OR 1.2, p < 0.05. Conclusions: Patients with smaller retinal AVR (<0.7 are likely to be at increased risk for CAD and carotid atherosclerosis in patients with NAFLD even without hypertension or diabetes.

  16. Down-regulation of pigment epithelium-derived factor in uveitic lesion associates with focal vascular endothelial growth factor expression and breakdown of the blood-retinal barrier.

    Science.gov (United States)

    Deeg, Cornelia A; Altmann, Frank; Hauck, Stefanie M; Schoeffmann, Stephanie; Amann, Barbara; Stangassinger, Manfred; Ueffing, Marius

    2007-05-01

    Spontaneous equine recurrent uveitis (ERU) is an incurable autoimmune disease affecting the eye. Identifying biological markers or pathways associated with this disease may allow the understanding of its pathogenesis at a molecular level. The vitreous is the body fluid closest to the disease-affected tissue and possibly also an effector of pathological processes relevant for ERU. Surgical removal of vitreous leads to cessation of relapses in spontaneous uveitis of both man and horse, therefore vitreous composites are likely to contribute to disease progression. Uveitic vitreous is likely to contain potential biomarkers in relatively undiluted quantities. With the goal to identify these markers, we systematically compared vitreous from healthy and disease-affected eyes by proteomic profiling. Nine differentially expressed proteins were identified, that are functionally related to immune response, inflammation, and maintenance of the blood-retinal barrier. One of these, pigment epithelium-derived factor, a protein involved in maintaining a proper blood-retina barrier as well as protecting from neoangiogenesis was additionally found to be down-regulated within uveitic retinal lesions whereas, conversely, vascular endothelial growth factor was found to be up-regulated at these sites. Together, these changes point to as of yet undiscovered biological pathways involved in the pathogenesis of this autoimmune disease.

  17. Deletion of miR-150 Exacerbates Retinal Vascular Overgrowth in High-Fat-Diet Induced Diabetic Mice.

    Science.gov (United States)

    Shi, Liheng; Kim, Andy Jeesu; Chang, Richard Cheng-An; Chang, Janet Ya-An; Ying, Wei; Ko, Michael L; Zhou, Beiyan; Ko, Gladys Yi-Ping

    2016-01-01

    Diabetic retinopathy (DR) is the leading cause of blindness among American adults above 40 years old. The vascular complication in DR is a major cause of visual impairment, making finding therapeutic targets to block pathological angiogenesis a primary goal for developing DR treatments. MicroRNAs (miRs) have been proposed as diagnostic biomarkers and potential therapeutic targets for various ocular diseases including DR. In diabetic animals, the expression levels of several miRs, including miR-150, are altered. The expression of miR-150 is significantly suppressed in pathological neovascularization in mice with hyperoxia-induced retinopathy. The purpose of this study was to investigate the functional role of miR-150 in the development of retinal microvasculature complications in high-fat-diet (HFD) induced type 2 diabetic mice. Wild type (WT) and miR-150 null mutant (miR-150-/-) male mice were given a HFD (59% fat calories) or normal chow diet. Chronic HFD caused a decrease of serum miR-150 in WT mice. Mice on HFD for 7 months (both WT and miR-150-/-) had significant decreases in retinal light responses measured by electroretinograms (ERGs). The retinal neovascularization in miR-150-/--HFD mice was significantly higher compared to their age matched WT-HFD mice, which indicates that miR-150 null mutation exacerbates chronic HFD-induced neovascularization in the retina. Overexpression of miR-150 in cultured endothelial cells caused a significant reduction of vascular endothelial growth factor receptor 2 (VEGFR2) protein levels. Hence, deletion of miR-150 significantly increased the retinal pathological angiogenesis in HFD induced type 2 diabetic mice, which was in part through VEGFR2.

  18. Inter-Eye Agreement in Measurement of Retinal Vascular Fractal Dimension in Patients with Type 1 Diabetes Mellitus

    DEFF Research Database (Denmark)

    Pedersen, Knud B; Broe, Rebecca; Grauslund, Jakob

    2016-01-01

    PURPOSE: To investigate inter-eye agreement in retinal vascular fractal dimension (FD) in patients with type 1 diabetes. METHODS: In a cross-sectional study, both eyes were exained in 178 patients with type 1 diabetes. All vessels in a zone 0.5-2.0 disc diameters from the optic disc were traced...... and FD calculated with the box-counting method using SIVA-Fractal semiautomatic software. The modified Early Treatment Diabetic Retinopathy Study (ETDRS) scale was used to grade diabetic retinopathy (DR). Pitman's test of difference in variance was used to calculated inter-eye agreement in FD according...

  19. Summarising the retinal vascular calibres in healthy, diabetic and diabetic retinopathy eyes.

    Science.gov (United States)

    Leontidis, Georgios; Al-Diri, Bashir; Hunter, Andrew

    2016-05-01

    Retinal vessel calibre has been found to be an important biomarker of several retinal diseases, including diabetic retinopathy (DR). Quantifying the retinal vessel calibres is an important step for estimating the central retinal artery and vein equivalents. In this study, an alternative method to the already established branching coefficient (BC) is proposed for summarising the vessel calibres in retinal junctions. This new method combines the mean diameter ratio with an alternative to Murray׳s cube law exponent, derived by the fractal dimension,experimentally, and the branch exponent of cerebral vessels, as has been suggested in previous studies with blood flow modelling. For the above calculations, retinal images from healthy, diabetic and DR subjects were used. In addition, the above method was compared with the BC and was also applied to the evaluation of arteriovenous ratio as a biomarker of progression from diabetes to DR in four consecutive years, i.e. three/two/one years before the onset of DR and the first year of DR. Moreover, the retinal arteries and veins around the optic nerve head were also evaluated. The new approach quantifies the vessels more accurately. The decrease in terms of the mean absolute percentage error was between 0.24% and 0.49%, extending at the same time the quantification beyond healthy subjects.

  20. Rationale and design of the AdRem study : Evaluating the effects of blood pressure lowering and intensive glucose control on vascular retinal disorders in patients with type 2 diabetes mellitus

    NARCIS (Netherlands)

    Stolk, Ronald P.; Vingerling, Johannes R.; Cruickshank, J. Kennedy; Hughes, Alun D.; Stanton, Alice; Lu Juming, [No Value; Patel, Anushka; Thom, Simon A. McG.; Grobbee, Diederick E.; Lu, J.M.

    2007-01-01

    The ADVANCE Retinal Measurements (AdRem) Study is a large intervention study evaluating the effects of target driven intensive glucose control and placebo controlled blood pressure lowering on retinal vascular changes. AdRem is a sub-study of the ADVANCE Study (Action in Diabetes and Vascular diseas

  1. Usefulness of anti-vascular endothelial growth factor combined with dexamethasone implant for retinal vein occlusion

    Directory of Open Access Journals (Sweden)

    Kim M

    2016-10-01

    Full Text Available Moosang Kim Department of Ophthalmology, School of Medcine, Kangwon National University, Chuncheon, Kangwon, KoreaI read with great interest the recent study by Michalska-Małecka et al1 published in the journal Clinical Interventions in Aging. The authors investigated the impact of intravitreal dexamethasone implant on macular morphology and functions in eyes with macular edema (ME secondary to branch retinal vein occlusion (BRVO or central retinal vein occlusion (CRVO. I congratulate the authors for their enlightening study and would like to make some contributions to the study.Read the original article by Michalska-Małecka and colleagues.

  2. Prediction of microRNAs affecting mRNA expression during retinal development

    Directory of Open Access Journals (Sweden)

    Cogliati Tiziana

    2010-01-01

    Full Text Available Abstract Background MicroRNAs (miRNAs are small RNA molecules (~22 nucleotides which have been shown to play an important role both in development and in maintenance of adult tissue. Conditional inactivation of miRNAs in the eye causes loss of visual function and progressive retinal degeneration. In addition to inhibiting translation, miRNAs can mediate degradation of targeted mRNAs. We have previously shown that candidate miRNAs affecting transcript levels in a tissue can be deduced from mRNA microarray expression profiles. The purpose of this study was to predict miRNAs which affect mRNA levels in developing and adult retinal tissue and to confirm their expression. Results Microarray expression data from ciliary epithelial retinal stem cells (CE-RSCs, developing and adult mouse retina were generated or downloaded from public repositories. Analysis of gene expression profiles detected the effects of multiple miRNAs in CE-RSCs and retina. The expression of 20 selected miRNAs was confirmed by RT-PCR and the cellular distribution of representative candidates analyzed by in situ hybridization. The expression levels of miRNAs correlated with the significance of their predicted effects upon mRNA expression. Highly expressed miRNAs included miR-124, miR-125a, miR-125b, miR-204 and miR-9. Over-expression of three miRNAs with significant predicted effects upon global mRNA levels resulted in a decrease in mRNA expression of five out of six individual predicted target genes assayed. Conclusions This study has detected the effect of miRNAs upon mRNA expression in immature and adult retinal tissue and cells. The validity of these observations is supported by the experimental confirmation of candidate miRNA expression and the regulation of predicted target genes following miRNA over-expression. Identified miRNAs are likely to be important in retinal development and function. Misregulation of these miRNAs might contribute to retinal degeneration and disease

  3. Moderate GSK-3β inhibition improves neovascular architecture, reduces vascular leakage, and reduces retinal hypoxia in a model of ischemic retinopathy.

    Science.gov (United States)

    Hoang, Mien V; Smith, Lois E H; Senger, Donald R

    2010-09-01

    In ischemic retinopathies, unrelieved hypoxia induces the formation of architecturally abnormal, leaky blood vessels that damage retina and ultimately can cause blindness. Because these newly formed blood vessels are functionally defective, they fail to alleviate underlying hypoxia, resulting in more pathological neovascularization and more damage to retina. With an established model of ischemic retinopathy, we investigated inhibition of glycogen synthase kinase-3β (GSK-3β) as a means for improving the architecture and functionality of pathological blood vessels in retina. In vitro, hypoxia increased GSK-3β activity in retinal endothelial cells, reduced β-catenin, and correspondingly impaired integrity of cell/cell junctions. Conversely, GSK-3β inhibitors restored β-catenin, improved cell/cell junctions, and enhanced the formation of capillary cords in three-dimensional collagen matrix. In vivo, GSK-3β inhibitors, at appropriately moderate doses, strongly reduced abnormal vascular tufts, reduced abnormal vascular leakage, and improved vascular coverage and perfusion during the proliferative phase of ischemia-driven retinal neovascularization. Most importantly, these improvements in neovasculature were accompanied by marked reduction in retinal hypoxia, relative to controls. Thus, GSK-3β inhibitors offer a promising strategy for alleviating retinal hypoxia by correcting key vascular defects typically associated with ischemia-driven neovascularization.

  4. Targeted knockdown of Cerkl, a retinal dystrophy gene, causes mild affectation of the retinal ganglion cell layer

    NARCIS (Netherlands)

    Garanto, A.; Vicente-Tejedor, J.; Riera, M.; Villa, P. de la; Gonzalez-Duarte, R.; Blanco, R.; Marfany, G.

    2012-01-01

    In order to approach the function of the retinal dystrophy CERKL gene we generated a novel knockout mouse model by cre-mediated targeted deletion of the Cerkl first exon and proximal promoter. The excised genomic region (2.3kb) encompassed the first Cerkl exon, upstream sequences including the proxi

  5. [Clinical associations between retinal vascular diseases and cardiovascular diseases in patients with systemic atheromatosis].

    Science.gov (United States)

    Stefănescu-Dima, Alin; Bătăiosu, Constantin; Sas, Teodor; Puianu, Mihaela

    2013-01-01

    A clinical study was conducted on a sample of 48 patients examined within 3 months. Of these, 27 patients were recruited by ophtalmologic criteria and 21 recruited by cardiologic criteria, 25% of these patients coming for routine check. They were investigated by ophthalmic examination, cardiological examination, imaging and laboratory examination. Testing has shown a strong link between cardiovascular disease and the eye of the patients investigated. The study demonstrated the need for interdisciplinary consultation for patients with vascular complaints in the carotid territory and a close correlation between the vascular and ophthalmologic pathology at this level.

  6. Retinal Vascular Fractals and Microvascular and Macrovascular Complications in Type 1 Diabetes

    DEFF Research Database (Denmark)

    Grauslund, Jakob; Green, Anders; Kawasaki, Ryo

    2010-01-01

    , nephropathy, neuropathy, and macrovascular disease (coronary heart disease, stroke, peripheral artery disease) was examined. RESULTS: Retinal fractals were gradable in at least 1 eye in 178 (86.6%) of 208 patients. Median age and duration of diabetes for these patients were 57.8 years and 42 years......% confidence interval [CI], 1.04-2.03) and neuropathy (OR, 1.42 per SD decrease in D(f); 95% CI, 1.01-2.01). There was also a trend of an association between lower D(f) and nephropathy (OR, 1.39 per SD decrease in D(f); 95% CI, 0.97-2.01) but not macrovascular disease. Furthermore, persons with lower D(f) were...... older. CONCLUSIONS: This study adds to the evidence that D(f) may have some role as a global measure of retinal vasculature and its association with systemic disease. Prospective studies clarifying this role are needed. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest...

  7. Reliability of Using Retinal Vascular Fractal Dimension as a Biomarker in the Diabetic Retinopathy Detection

    Science.gov (United States)

    Zhang, Jiong; Bekkers, Erik; Abbasi-Sureshjani, Samaneh

    2016-01-01

    The retinal fractal dimension (FD) is a measure of vasculature branching pattern complexity. FD has been considered as a potential biomarker for the detection of several diseases like diabetes and hypertension. However, conflicting findings were found in the reported literature regarding the association between this biomarker and diseases. In this paper, we examine the stability of the FD measurement with respect to (1) different vessel annotations obtained from human observers, (2) automatic segmentation methods, (3) various regions of interest, (4) accuracy of vessel segmentation methods, and (5) different imaging modalities. Our results demonstrate that the relative errors for the measurement of FD are significant and FD varies considerably according to the image quality, modality, and the technique used for measuring it. Automated and semiautomated methods for the measurement of FD are not stable enough, which makes FD a deceptive biomarker in quantitative clinical applications.

  8. Retinal arterioles narrow with increasing duration of anti-retroviral therapy in HIV infection: a novel estimator of vascular risk in HIV?

    Directory of Open Access Journals (Sweden)

    Sophia Pathai

    Full Text Available OBJECTIVES: HIV infection is associated with an increased risk of age-related morbidity mediated by immune dysfunction, atherosclerosis and inflammation. Changes in retinal vessel calibre may reflect cumulative structural damage arising from these mechanisms. The relationship of retinal vessel calibre with clinical and demographic characteristics was investigated in a population of HIV-infected individuals in South Africa. METHODS: Case-control study of 491 adults ≥30 years, composed of 242 HIV-infected adults and 249 age- and gender-matched HIV-negative controls. Retinal vessel calibre was measured using computer-assisted techniques to determine mean arteriolar and venular diameters of each eye. RESULTS: The median age was 40 years (IQR: 35-48 years. Among HIV-infected adults, 87.1% were receiving highly active antiretroviral therapy (HAART (median duration, 58 months, their median CD4 count was 468 cells/µL, and 84.3% had undetectable plasma viral load. Unadjusted mean retinal arteriolar diameters were 163.67±17.69 µm in cases and 161.34±17.38 µm in controls (p = 0.15. Unadjusted mean venular diameters were 267.77±18.21 µm in cases and 270.81±18.98 µm in controls (p = 0.07. Age modified the effect of retinal arteriolar and venular diameters in relation to HIV status, with a tendency towards narrower retinal diameters in HIV cases but not in controls. Among cases, retinal arteriolar diameters narrowed with increasing duration of HAART, independently of age (167.83 µm 6 years, p-trend = 0.02, and with a HIV viral load >10,000 copies/mL while on HAART (p = 0.05. HIV-related venular changes were not detected. CONCLUSIONS: Narrowing of retinal arteriolar diameters is associated with HAART duration and viral load, and may reflect heightened inflammatory and pro-atherogenic states of the systemic vasculature. Measurement of retinal vascular calibre could be an innovative non-invasive method of estimating vascular risk in HIV

  9. Fucoidan reduces secretion and expression of vascular endothelial growth factor in the retinal pigment epithelium and reduces angiogenesis in vitro.

    Directory of Open Access Journals (Sweden)

    Michaela Dithmer

    Full Text Available Fucoidan is a polysaccharide isolated from brown algae which is of current interest for anti-tumor therapy. In this study, we investigated the effect of fucoidan on the retinal pigment epithelium (RPE, looking at physiology, vascular endothelial growth factor (VEGF secretion, and angiogenesis, thus investigating a potential use of fucoidan for the treatment of exudative age-related macular degeneration. For this study, human RPE cell line ARPE-19 and primary porcine RPE cells were used, as well as RPE/choroid perfusion organ cultures. The effect of fucoidan on RPE cells was investigated with methyl thiazolyl tetrazolium--assay, trypan blue exclusion assay, phagocytosis assay and a wound healing assay. VEGF expression was evaluated in immunocytochemistry and Western blot, VEGF secretion was evaluated in ELISA. The effect of fucoidan on angiogenesis was tested in a Matrigel assay using calcein-AM vital staining, evaluated by confocal laser scanning microcopy and quantitative image analysis. Fucoidan displays no toxicity and does not diminish proliferation or phagocytosis, but reduces wound healing in RPE cells. Fucoidan decreases VEGF secretion in RPE/choroid explants and RPE cells. Furthermore, it diminishes VEGF expression in RPE cells even when co-applied with bevacizumab. Furthermore, fucoidan reduces RPE-supernatant- and VEGF-induced angiogenesis of peripheral endothelial cells. In conclusion, fucoidan is a non-toxic agent that reduces VEGF expression and angiogenesis in vitro and may be of interest for further studies as a potential therapy against exudative age-related macular degeneration.

  10. Vascular endothelial growth factor up-regulates the expression of intracellular adhesion molecule-1 in retinal endothelial cells via reactive oxygen species, but not nitric oxide

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiao-ling; WEN Liang; CHEN Yan-jiong; ZHU Yi

    2009-01-01

    Background The vascular endothelial growth factor (VEGF) is involved in the initiation of retinal vascular leakage and nonperfusion in diabetes. The intracellular adhesion molecule-1 (ICAM-1) is the key mediator of the effect of VEGFs on retinal leukostasis. Although the VEGF is expressed in an early-stage diabetic retina, whether it directly up-regulates ICAM-1 in retinal endothelial cells (ECs) is unknown. In this study, we provided a new mechanism to explain that VEGF does up-regulate the expression of ICAM-1 in retinal ECs.Methods Bovine retinal ECs (BRECs) were isolated and cultured. Immunohistochemical staining was performed to identify BRECs. The cultured cells were divided into corresponding groups. Then, VEGF (100 ng/ml) and other inhibitors were used to treat the cells. Cell lysate and the cultured supernatant were collected, and then, the protein level of ICAM-1 and phosphorylation of the endothelial nitric oxide synthase (eNOS) were detected using Western blotting. Griess reaction was used to detect nitric oxide (NO).Results Western blotting showed that the VEGF up-regulated the expression of ICAM-1 protein and increased phosphorylation of the eNOS in retinal ECs. Neither the block of NO nor protein kinase C (PKC) altered the expression of ICAM-1 or the phosphorylation of eNOS. The result of the Western blotting also showed that inhibition of phosphatidylinositol 3-kinase (PI3K) or reactive oxygen species (ROS) significantly reduced the expression of ICAM-1. Inhibition of PI3K also reduced phosphorylation of eNOS. Griess reaction showed that VEGF significantly increased during NO production. When eNOS was blocked by L-NAME or PI3K was blocked by LY294002, the basal level of NO production and the increment of NO caused by VEGF could be significantly decreased.Conclusion ROS-NO coupling in the retinal endothelium may be a new mechanism that could help to explain why VEGF induces ICAM-1 expression and the resulting leukostasis in diabetic retinopathy.

  11. 视网膜血管异常与脑小血管病%Retinal vascular abnormalities and cerebral small vessel disease

    Institute of Scientific and Technical Information of China (English)

    李華; 吴丹紅

    2014-01-01

    Cerebral small vessel disease is common and is gradually being understood,but it is difficult to visualize directly in the body.The retinal vessels share the similar anatomic,physiological,and embryological characteristics with the cerebral small vessels.Their changes may reflect the changes of cerebral small vessels in a certain extent.Studies in recent years have shown that retinal vascular abnormalities are associated with lacunar infarction and white matter lesions.This article summarizes the research evidence of the correlation of between retinal vascular abnormalities and cerebral small vessel disease.%脑小血管病很常见并逐渐被认识,但在体内很难直接观察.视网膜血管与脑小血管具有相似的解剖学、生理学和胚胎学特征,其改变可能在一定程度上能反映脑小血管改变.近年来的研究显示,视网膜血管异常与腔隙性梗死和脑白质病变相关.文章对视网膜血管异常与脑小血管病相关性的研究证据进行了总结.

  12. Mechanism of retinal pigment epithelium tear formation following intravitreal anti-vascular endothelial growth factor therapy revealed by spectral-domain optical coherence tomography

    DEFF Research Database (Denmark)

    Nagiel, Aaron; Freund, K Bailey; Spaide, Richard F;

    2013-01-01

    PURPOSE: To demonstrate the mechanism by which retinal pigment epithelium (RPE) tears occur in eyes with neovascular age-related macular degeneration (AMD) treated with intravitreal anti-vascular endothelial growth factor (VEGF) agents using spectral-domain optical coherence tomography (OCT......). DESIGN: Retrospective observational case series. METHODS: OCT images of 8 eyes that developed RPE tears following the administration of intravitreal anti-VEGF agents for neovascular AMD were evaluated. Pretear and posttear images were compared in order to elucidate the mechanism by which RPE tears occur...... to the retracted RPE. In all eyes, the RPE ruptured along a segment of bare RPE not in contact with the CNV or Bruch membrane. CONCLUSIONS: Eyes with vascularized PEDs secondary to AMD may show specific OCT findings that increase the risk for RPE tear following intravitreal anti-VEGF injection. Rapid involution...

  13. The Factors Affecting Success of Pneumatic Retinopexy in Treatment of Retinal Detachment

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    Kemal Yüksel

    2016-06-01

    Full Text Available Objective: To present the factors that influence the suc­cess rate of pneumatic retinopexy on rhegmatogenous retinal detachment treatment. Methods: Ninety eyes of 29 female and 61 male patient were included to the study. The patient’s age, sex, du­ration of symptoms, the best corrected visual acuities (BCVA on the time of application, lens status, preopera­tive retinal tear number and location, retinal detachment size, macular involvement, tamponade type, coexisting complications, and anatomic success rates were record­ed at preoperative, postoperative 3rd months and final examination. Results: Only one treatment session success number was 55 over 90 (61.1% patients. Median preoperative, postoperative 3rd month and final examination Log­MAR BCVA values were 1.3, 0.5 and 0.5 respectively.(p=0.0001 Preoperative and postoperative other param­eters was not revealed significant differences with one treatment session. However there was a significant posi­tive correlation between the detachment size and ana­tomical success. (p=0.03, r=0.324 Conclusion: Pneumatic retinopexy is an alternative treat­ment option for the anatomical and functional success in retinal detachment at suitable patients. In our study the success rate was higher in patients with less than 3 clock dial retinal detachment patients.

  14. Dorzolamide increases retinal oxygen tension after branch retinal vein occlusion

    DEFF Research Database (Denmark)

    Noergaard, Michael Hove; Bach-Holm, Daniella; Scherfig, Erik;

    2008-01-01

    To study the effect of dorzolamide on the preretinal oxygen tension (RPO(2)) in retinal areas affected by experimental branch retinal vein occlusion (BRVO) in pigs.......To study the effect of dorzolamide on the preretinal oxygen tension (RPO(2)) in retinal areas affected by experimental branch retinal vein occlusion (BRVO) in pigs....

  15. 合并视网膜大血管阻塞的系统性红斑狼疮的临床观察%Clinical observation of systemic lupus erythematosus complicated with major retinal vascular occlusion

    Institute of Scientific and Technical Information of China (English)

    陈乔; 聂尚武; 王晓琴; 陈盼

    2015-01-01

    ?AIM: To observe the clinical characteristics of the patients with systemic lupus erythematosus ( SLE ) complicated with major retinal vascular occlusion. ?METHODS:Seventeen patients ( 21 eyes ) with SLE complicated with major retinal vascular occlusion were selected as the experimental group from January 2010 to January 2014 in our hospital.Thirty cases ( 60 eyes ) of SLE patients without retinopathy were selected as the control group. Ocular and systemic examination and related laboratory tests, including various autoimmune antibodies, were taken. Clinical symptoms and signs were recorded. ?RESULTS:In the experimental group, 13 cases were uniocular, 4 cases were bilocular, in which there were central retinal vein occlusion ( CRVO ) in 7 eyes ( 33%) , branch retinal vein occlusion ( BRVO ) in 9 eyes ( 43%) , central retinal artery occlusion (CRAO) in 3 eyes(14%), branch retinal artery occlusion ( BRAO ) in 1 eye ( 5%) , CRAO combined with CRVO in 1 eye ( 5%).The best corrected visual acuity ( BCVA ) of the experimental group was significantly worse than that of the control group.The incidence of skin erythema ( 76%) , fever ( 59%) , arthritis ( 53%) , central nervous system symptoms ( headache and neuropsychiatric abnormalities) ( 76%) , pleurisy ( 41%) were significantly higher than those of the control group.The positive rate of anti ds-DNA antibody ( 100%) and antiphospholipid antibody (65%), the decrease of C3(82%), the elevation of erythrocyte sedimentation rate ( 100%) , thrombocytopenia ( 65%) were significantly higher than those of the control group. The score of SLEDAI ( systemic lupus erythematosus disease activity index ) was 20.24 ±4.66 prompting SLE in moderate or severe active stage. ? CONCLUSION: In SLE patients with major retinal vascular occlusion, the visual acuity was severely damaged, the multi-system was affected in varying degrees, and all of the patients were in moderate and severe activity period. There may be a correlation between

  16. Vascular adaptive responses to physical exercise and to stress are affected differently by nandrolone administration

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    T. Bruder-Nascimento

    2011-04-01

    Full Text Available Androgenic anabolic steroid, physical exercise and stress induce cardiovascular adaptations including increased endothelial function. The present study investigated the effects of these conditions alone and in combination on the vascular responses of male Wistar rats. Exercise was started at 8 weeks of life (60-min swimming sessions 5 days per week for 8 weeks, while carrying a 5% body-weight load. One group received nandrolone (5 mg/kg, twice per week for 8 weeks, im. Acute immobilization stress (2 h was induced immediately before the experimental protocol. Curves for noradrenaline were obtained for thoracic aorta, with and without endothelium from sedentary and trained rats, submitted or not to stress, treated or not with nandrolone. None of the procedures altered the vascular reactivity to noradrenaline in denuded aorta. In intact aorta, stress and exercise produced vascular adaptive responses characterized by endothelium-dependent hyporeactivity to noradrenaline. These conditions in combination did not potentiate the vascular adaptive response. Exercise-induced vascular adaptive response was abolished by nandrolone. In contrast, the aortal reactivity to noradrenaline of sedentary rats and the vascular adaptive response to stress of sedentary and trained rats were not affected by nandrolone. Maximum response for 7-10 rats/group (g: sedentary 3.8 ± 0.2 vs trained 3.0 ± 0.2*; sedentary/stress 2.7 ± 0.2 vs trained/stress 3.1 ± 0.1*; sedentary/nandrolone 3.6 ± 0.1 vs trained/nandrolone 3.8 ± 0.1; sedentary/stress/nandrolone 3.2 ± 0.1 vs trained/stress/nandrolone 2.5 ± 0.1*; *P < 0.05 compared to its respective control. Stress and physical exercise determine similar vascular adaptive response involving distinct mechanisms as indicated by the observation that only the physical exercise-induced adaptive response was abolished by nandrolone.

  17. Dietary n-3 and n-6 PUFA enhance DHA incorporation in retinal phospholipids without affecting PGE(1) and PGE (2) levels.

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    Schnebelen, Coralie; Grégoire, Stéphane; Pasquis, Bruno; Joffre, Corinne; Creuzot-Garcher, Catherine P; Bron, Alain M; Bretillon, Lionel; Acar, Niyazi

    2009-05-01

    The purpose of this study was to determine whether dietary n-3 and n-6 PUFA may affect retinal PUFA composition and PGE(1) and PGE(2) production. Male Wistar rats were fed for 3 months with diets containing: (1) 10% eicosapentaenoic acid (EPA) and 7% docosahexaenoic acid (DHA), or (2) 10% gamma-linolenic acid (GLA), or (3) 10% EPA, 7% DHA and 10% GLA, or (4) a balanced diet deprived of EPA, DHA, and GLA. The fatty acid composition of retinal phospholipids was determined by gas chromatography. Prostaglandin production was measured by enzyme immunoassay. When compared to rats fed the control diet, the retinal levels of DHA were increased in rats fed both diets enriched with n-3 PUFA (EPA + DHA and EPA + DHA + GLA diets) and decreased in those supplemented with n-6 PUFA only (GLA diet). The diet enriched with both n-6 and n-3 PUFA resulted in the greatest increase in retinal DHA. The levels of PGE(1) and PGE(2) were significantly increased in retinal homogenates of rats fed with the GLA-rich diet when compared with those of animals fed the control diet. These higher PGE(1) and PGE(2) levels were not observed in animals fed with EPA + DHA + GLA. In summary, GLA added to EPA + DHA resulted in the highest retinal DHA content but without increasing retinal PGE(2) as seen in animals supplemented with GLA only.

  18. Discovery of a novel class of targeted kinase inhibitors that blocks protein kinase C signaling and ameliorates retinal vascular leakage in a diabetic rat model.

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    Grant, Stephan; Tran, Phong; Zhang, Qin; Zou, Aihua; Dinh, Dac; Jensen, Jordan; Zhou, Sue; Kang, Xiaolin; Zachwieja, Joseph; Lippincott, John; Liu, Kevin; Johnson, Sarah Ludlum; Scales, Stephanie; Yin, Chunfeng; Nukui, Seiji; Stoner, Chad; Prasanna, Ganesh; Lafontaine, Jennifer; Wells, Peter; Li, Hui

    2010-02-10

    Protein kinase C (PKC) family members such as PKCbetaII may become activated in the hyperglycemic state associated with diabetes. Preclinical and clinical data implicate aberrant PKC activity in the development of diabetic microvasculature abnormalities. Based on this potential etiological role for PKC in diabetic complications, several therapeutic PKC inhibitors have been investigated in clinical trials for the treatment of diabetic patients. In this report, we present the discovery and preclinical evaluation of a novel class of 3-amino-pyrrolo[3,4-c]pyrazole derivatives as inhibitors of PKC that are structurally distinct from the prototypical indolocarbazole and bisindolylmaleimide PKC inhibitors. From this pyrrolo-pyrazole series, several compounds were identified from biochemical assays as potent, ATP-competitive inhibitors of PKC activity with high specificity for PKC over other protein kinases. These compounds were also found to block PKC signaling activity in multiple cellular functional assays. PF-04577806, a representative from this series, inhibited PKC activity in retinal lysates from diabetic rats stimulated with phorbol myristate acetate. When orally administered, PF-04577806 showed good exposure in the retina of diabetic Long-Evans rats and ameliorated retinal vascular leakage in a streptozotocin-induced diabetic rat model. These novel PKC inhibitors represent a promising new class of targeted protein kinase inhibitors with potential as therapeutic agents for the treatment of patients with diabetic microvascular complications.

  19. Hereditary retinal eye diseases in childhood and youth affecting the central retina

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    Martin M Nentwich

    2013-01-01

    Classic examinations for patients suffering from hereditary retinal dystrophies of the central retina are funduscopy - also using red-free light - visual-field tests, electrophysiologic tests as electro-retinogram [ERG] and multifocal ERG and tests evaluating color vision. Recently, new imaging modalities have been introduced into the clinical practice. The significance of these new methods such as high-resolution spectral-domain optic coherence tomography [SD-OCT] and fundus autofluorescence will be discussed as well as "next generation sequencing" as a new method for the analysis of genetic mutations in a larger number of patients.

  20. The Argus™ II retinal prosthesis: factors affecting patient selection for implantation.

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    Ahuja, Ashish Kishore; Behrend, Matthew R

    2013-09-01

    The Argus II epiretinal prosthesis has been developed to provide partial restoration of vision to subjects blinded from outer retinal degenerative disease. To date, the device has been implanted in multiple subjects with profound retinitis pigmentosa as part of a worldwide clinical feasibility study (clinicaltrials.gov ID: NCT00407602). The Argus II is intended to provide partial restoration of functional vision. Most subjects showed an improvement in tasks assessing orientation & mobility, spatial-motor localization, and ability of discerning the direction of motion of moving stimuli. Roughly one third of subjects experienced measurable improvement in visual acuity with the implant. Some subjects identified words with high accuracy, a result that has also been reported by the leading subretinal implant group. Perceptual threshold was correlated with electrode-retina distance, electrode-fovea distance, and light sensitivity, either as single variables or in bivariate linear regression. Taken together these three variables may be used to inform patient selection and develop algorithms for the fitting of higher-electrode count systems. Visual acuity for future generations of the Argus implant may not hit theoretical limitations until arrays hold an excess of several hundreds of electrodes. Nevertheless, preliminary safety and efficacy data are supportive of the development of higher-resolution systems that target macular placement from implant design and surgical perspectives.

  1. Rgcs1, a dominant QTL that affects retinal ganglion cell death after optic nerve crush in mice

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    Schlamp Cassandra L

    2008-07-01

    Full Text Available Abstract Background Intrinsic apoptosis of neuronal somas is one aspect of neurodegenerative diseases that can be influenced by genetic background. Genes that affect this process may act as susceptibility alleles that contribute to the complex genetic nature of these diseases. Retinal ganglion cell death is a defining feature of the chronic and genetically complex neurodegenerative disease glaucoma. Previous studies using an optic nerve crush procedure in inbred mice, showed that ganglion cell resistance to crush was affected by the Mendelian-dominant inheritance of 1–2 predicted loci. To assess this further, we bred and phenotyped a large population of F2 mice derived from a resistant inbred strain (DBA/2J and a susceptible strain (BALB/cByJ. Results Genome wide mapping of the F2 mice using microsatellite markers, detected a single highly significant quantitative trait locus in a 25 cM (58 Mb interval on chromosome 5 (Chr5.loc34-59 cM. No interacting loci were detected at the resolution of this screen. We have designated this locus as Retinal ganglion cell susceptible 1, Rgcs1. In silico analysis of this region revealed the presence of 578 genes or expressed sequence tags, 4 of which are highly expressed in the ganglion cell layer of the mammalian retina, and 2 of which are suspected susceptibility alleles in chronic neurodegenerative diseases. In addition, 25 genes contain 36 known single nucleotide polymorphisms that create nonsynonymous amino acid changes between the two parental strains. Collectively, this analysis has identified 7 potential candidate genes that may affect ganglion cell death. Conclusion The process of ganglion cell death is likely one of the many facets of glaucoma susceptibility. A novel dominant locus has been identified that affects sensitivity of ganglion cells to optic nerve crush. The allele responsible for this sensitivity may also be a susceptibility allele for glaucoma.

  2. Rescuing axons from degeneration does not affect retinal ganglion cell death

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    S. de Lima

    2016-01-01

    Full Text Available After a traumatic injury to the central nervous system, the distal stumps of axons undergo Wallerian degeneration (WD, an event that comprises cytoskeleton and myelin breakdown, astrocytic gliosis, and overexpression of proteins that inhibit axonal regrowth. By contrast, injured neuronal cell bodies show features characteristic of attempts to initiate the regenerative process of elongating their axons. The main molecular event that leads to WD is an increase in the intracellular calcium concentration, which activates calpains, calcium-dependent proteases that degrade cytoskeleton proteins. The aim of our study was to investigate whether preventing axonal degeneration would impact the survival of retinal ganglion cells (RGCs after crushing the optic nerve. We observed that male Wistar rats (weighing 200-400 g; n=18 treated with an exogenous calpain inhibitor (20 mM administered via direct application of the inhibitor embedded within the copolymer resin Evlax immediately following optic nerve crush showed a delay in the onset of WD. This delayed onset was characterized by a decrease in the number of degenerated fibers (P<0.05 and an increase in the number of preserved fibers (P<0.05 4 days after injury. Additionally, most preserved fibers showed a normal G-ratio. These results indicated that calpain inhibition prevented the degeneration of optic nerve fibers, rescuing axons from the process of axonal degeneration. However, analysis of retinal ganglion cell survival demonstrated no difference between the calpain inhibitor- and vehicle-treated groups, suggesting that although the calpain inhibitor prevented axonal degeneration, it had no effect on RGC survival after optic nerve damage.

  3. Effects of estradiol on uterine perfusion in anesthetized cyclic mares affected with uterine vascular elastosis.

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    Esteller-Vico, A; Liu, I K M; Vaughan, B; Steffey, E P; Brosnan, R J

    2016-01-01

    Uterine vascular elastosis in mares is characterized by degeneration of uterine vasculature through thickening of the elastin layers. Factors commonly associated with this degeneration include age, parity, and chronic uterine endometritis. Affected mares have also been shown to exhibit decreases in uterine blood flow and perfusion of the uterus. Due to the increased thickness of the elastin layers, we hypothesize that vasodilatation of the uterine vasculature is also impaired. To test the functionality of these vessels, we evaluated the vasodilatory effects of estradiol on the uterine vascular bed in mares with normal vasculature and mares with severe elastosis. Both groups were tested in estrus and diestrus. Fluorescent microspheres were used to determine basal blood perfusion, followed by the intravenous administration of 1.0 μg/kg of 17β-estradiol. After 90 min, perfusion was measured once again to determine the vascular response to estradiol. Control mares in estrus displayed a significant increase in total uterine blood flow after the administration of estradiol when compared to baseline levels. No other group had a significant increase in total blood flow and perfusion after estradiol administration. The administration of estradiol in control mares induced regional increases in perfusion in the uterine horns and uterine body during estrus and only in the uterine horns during diestrus. Mares affected by elastosis exhibited no regional differences in perfusion levels post-estradiol administration. The difference in the vasodilatory response induced by estradiol between reproductively healthy mares and mares affected with elastosis indicates that the functionality of the affected vessels is compromised.

  4. Measurement and influencing factors on retinal vascular caliber%视网膜血管管径测量方法的进展及其影响因素

    Institute of Scientific and Technical Information of China (English)

    李满; 杨永升; 安娜; 庄曾渊

    2014-01-01

    视网膜血管是人体唯一肉眼可见的血管,通过评价视网膜微血管病变的程度可提示系统性微血管病变的状况。本文介绍视网膜血管管径测量方法的进展及其影响因素。%Retinal vessel is the only visible vessels in human body and systemic microvascular lesions could be evaluated by the degree of retinal vessels. ln this article, the progress of retinal vascular caliber measuring method and its influencing factors were briefly reviewed.

  5. 视网膜血管阻塞介入治疗中的护理%The Nursing for Retinal Vascular Occlusion with Intervention Treatment

    Institute of Scientific and Technical Information of China (English)

    严真真; 崔会来; 李静; 孙则红; 张冬梅

    2011-01-01

    Objective: The study focuses on the value of nursing in the intervention treatment of retinal vascular occlusion. Method: The treatment of retinal vascular occlusion by super selective ophthalmic artery thrombolysis is the application of the interventiona]radiology in the ophthalmology. Some nursing experience was drawn from 7 cases before, in and after surgery. Even out-of-hospital attendance instructions were given as regard to the prevention, processing and nursing of complications. Result: Psychological and basic physical nursing before surgery should be well done; cooperation with the doctors in the surgery ensures the success of the operation; close attention should be paid to the blood pressure, the movement of the central and peripheral nerve system, sensory changes and visual changes; more attention should also be paid to the hematoma and bleeding in the puncture and other complications; blood sugar and blood pressure should be kept normal by taking small dose of persantine and aspirin to counter thrombotic and reduce peripheral arterial thrombosis. Conclusion: The nursing measures for the 7 cases with retinal vascular occlusion have shown that the monolithic nursing plays a positive role in ophthalmonogy nursing.%目的:探讨护理工作在视网膜血管阻塞介入治疗中的价值.方法:超选择性眼动脉溶栓治疗视网膜血管阻塞疾病,是介入放射学在眼科领域实际应用的新方法.结合7例病人的护理经验,总结了术前、术中、术后及出院指导的护理要点及并发症的预防、处理、护理措施.结果:提出术前应认真做好心理护理和基础护理;术中积极配合医生治疗工作,保障手术顺利进行;术后要严密观察血压、中枢神经和周围神经的运动、感觉的变化及视力的改变,同时要重视对穿刺部位血肿、出血等并发症的观察;出院后继续控制血糖、血压,仍需小剂量服用潘生丁、阿司匹林,以抗血

  6. Host tree phenology affects vascular epiphytes at the physiological, demographic and community level.

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    Einzmann, Helena J R; Beyschlag, Joachim; Hofhansl, Florian; Wanek, Wolfgang; Zotz, Gerhard

    2014-11-11

    The processes that govern diverse tropical plant communities have rarely been studied in life forms other than trees. Structurally dependent vascular epiphytes, a major part of tropical biodiversity, grow in a three-dimensional matrix defined by their hosts, but trees differ in their architecture, bark structure/chemistry and leaf phenology. We hypothesized that the resulting seasonal differences in microclimatic conditions in evergreen vs. deciduous trees would affect epiphytes at different levels, from organ physiology to community structure. We studied the influence of tree leaf phenology on vascular epiphytes on the Island of Barro Colorado, Panama. Five tree species were selected, which were deciduous, semi-deciduous or evergreen. The crowns of drought-deciduous trees, characterized by sunnier and drier microclimates, hosted fewer individuals and less diverse epiphyte assemblages. Differences were also observed at a functional level, e.g. epiphyte assemblages in deciduous trees had larger proportions of Crassulacean acid metabolism species and individuals. At the population level a drier microclimate was associated with lower individual growth and survival in a xerophytic fern. Some species also showed, as expected, lower specific leaf area and higher δ(13)C values when growing in deciduous trees compared with evergreen trees. As hypothesized, host tree leaf phenology influences vascular epiphytes at different levels. Our results suggest a cascading effect of tree composition and associated differences in tree phenology on the diversity and functioning of epiphyte communities in tropical lowland forests.

  7. Evaluation of geometric features as biomarkers of diabetic retinopathy for characterizing the retinal vascular changes during the progression of diabetes.

    Science.gov (United States)

    Leontidis, Georgios; Al-Diri, Bashir; Wigdahl, Jeffrey; Hunter, Andrew

    2015-01-01

    Diabetic retinopathy (DR) has been widely studied and characterized. However, until now, it is unclear how different features, extracted from the retinal vasculature, can be associated with the progression of diabetes and therefore become biomarkers of DR. In this study, a comprehensive analysis is presented, in which four groups were created, using eighty fundus images from twenty patients, who have progressed to DR and they had no history of any other diseases (e.g. hypertension or glaucoma). The significance of the following features was evaluated: widths, angles, branching coefficient (BC), angle-to-BC ratio, standard deviations, means and medians of widths and angles, fractal dimension (FD), lacunarity and FD-to-lacunarity ratio, using a mixed model analysis of variance (ANOVA) design. All the features were measured from the same junctions of each patient, using an automated tool. The discriminative power of these features was evaluated, using decision trees and random forests classifiers. Cross validation and out-of-bag error were used to evaluate the classifiers' performance, calculating the area under the ROC curve (AUC) and the classification error. Widths, FD and FD-to-Lacunarity ratio were found to differ significantly. Random forests had a superior performance of 0.768 and 0.737 in the AUC for the two cases of classification, namely three-years-pre-DR/post-DR and two-years-pre-DR/post-DR respectively.

  8. Oxalomalate reduces expression and secretion of vascular endothelial growth factor in the retinal pigment epithelium and inhibits angiogenesis: Implications for age-related macular degeneration

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    Sung Hwan Kim

    2016-12-01

    Full Text Available Clinical and experimental observations indicate a critical role for vascular endothelial growth factor (VEGF, secreted by the retinal pigment epithelium (RPE, in pathological angiogenesis and the development of choroidal neovascularization (CNV in age-related macular degeneration (AMD. RPE-mediated VEGF expression, leading to angiogenesis, is a major signaling mechanism underlying ocular neovascular disease. Inhibiting this signaling pathway with a therapeutic molecule is a promising anti-angiogenic strategy to treat this disease with potentially fewer side effects. Oxalomalate (OMA is a competitive inhibitor of NADP+-dependent isocitrate dehydrogenase (IDH, which plays an important role in cellular signaling pathways regulated by reactive oxygen species (ROS. Here, we have investigated the inhibitory effect of OMA on the expression of VEGF, and the associated underlying mechanism of action, using in vitro and in vivo RPE cell models of AMD. We found that OMA reduced the expression and secretion of VEGF in RPE cells, and consequently inhibited CNV formation. This function of OMA was linked to its capacity to activate the pVHL-mediated HIF-1α degradation in these cells, partly via a ROS-dependent ATM signaling axis, through inhibition of IDH enzymes. These findings reveal a novel role for OMA in inhibiting RPE-derived VEGF expression and angiogenesis, and suggest unique therapeutic strategies for treating pathological angiogenesis and AMD development.

  9. AUTOMATIC RETINAL VESSEL TORTUOSITY MEASUREMENT

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    Nidhal Khdhair El Abbadi

    2013-01-01

    Full Text Available Retinal vascular vessels have the role to indicate the retinal diseases and for systematic diseases when there are any abnormalities in retinal vascular pattern. A characteristic of the vascular pattern that is appreciated by clinicians is vascular tortuosity, i.e., how curved or kinked a blood vessel, either vein or artery, appears along its course. In this study we suggest a novel mask filter to track the blood vessel along its course and measuring the blood vessels tortuosity over the entire human retinal vessel network in fundus eye image, by using the arc to chord ratio. The suggested algorithm tested with straight and curve hand drawing lines and gives high accurate results.

  10. High glucose alters retinal astrocytes phenotype through increased production of inflammatory cytokines and oxidative stress.

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    Eui Seok Shin

    Full Text Available Astrocytes are macroglial cells that have a crucial role in development of the retinal vasculature and maintenance of the blood-retina-barrier (BRB. Diabetes affects the physiology and function of retinal vascular cells including astrocytes (AC leading to breakdown of BRB. However, the detailed cellular mechanisms leading to retinal AC dysfunction under high glucose conditions remain unclear. Here we show that high glucose conditions did not induce the apoptosis of retinal AC, but instead increased their rate of DNA synthesis and adhesion to extracellular matrix proteins. These alterations were associated with changes in intracellular signaling pathways involved in cell survival, migration and proliferation. High glucose conditions also affected the expression of inflammatory cytokines in retinal AC, activated NF-κB, and prevented their network formation on Matrigel. In addition, we showed that the attenuation of retinal AC migration under high glucose conditions, and capillary morphogenesis of retinal endothelial cells on Matrigel, was mediated through increased oxidative stress. Antioxidant proteins including heme oxygenase-1 and peroxiredoxin-2 levels were also increased in retinal AC under high glucose conditions through nuclear localization of transcription factor nuclear factor-erythroid 2-related factor-2. Together our results demonstrated that high glucose conditions alter the function of retinal AC by increased production of inflammatory cytokines and oxidative stress with significant impact on their proliferation, adhesion, and migration.

  11. Serum lipid profiles and dyslipidaemia are associated with retinal microvascular changes in children and adolescents

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    Xiao, Wei; Guo, Xinxing; Ding, Xiaohu; He, Mingguang

    2017-01-01

    The present study aims to assess the relationship between serum lipid parameters and retinal microvascular calibres in children and adolescents. A total of 950 participants aged 7 to 19 years were recruited. Central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent (CRVE) were measured from digital retinal images. Serological testing was performed to obtain lipid profiles. Dyslipidaemia was defined according to the US national expert panel guideline. After adjusted for age, sex, mean arterial blood pressure, axial length, body mass index and the fellow retinal vascular calibre, no significant association was found between retinal vascular diameters and any lipid parameters (all P > 0.05) in children younger than 12 years. Among the adolescents 12 years and older, increased triglycerides, total cholesterol, low-density lipoprotein cholesterol, and apoB were associated with decrease in CRAE (β = −1.33, −1.83, −1.92 and −7.18, P = 0.031, 0.003, 0.006, and 0.009, respectively). Compared with normolipidemic counterparts, adolescents with dyslipidaemia had significantly narrower retinal arteriolar diameters. No significant relationship between lipid subclass levels and CRVE was revealed in adolescents. The present findings suggest that the elevation of atherogenic lipids in adolescents is closely related to the adverse changes of retinal arterioles. Dyslipidaemia may affect systemic microvasculature from childhood on. PMID:28317946

  12. Hypothyroidism Affects Vascularization and Promotes Immune Cells Infiltration into Pancreatic Islets of Female Rabbits

    Science.gov (United States)

    Rodríguez-Castelán, Julia; Martínez-Gómez, Margarita; Castelán, Francisco; Cuevas, Estela

    2015-01-01

    Thyroidectomy induces pancreatic edema and immune cells infiltration similarly to that observed in pancreatitis. In spite of the controverted effects of hypothyroidism on serum glucose and insulin concentrations, the number and proliferation of Langerhans islet cells as well as the presence of extracellular matrix are affected depending on the islet size. In this study, we evaluated the effect of methimazole-induced hypothyroidism on the vascularization and immune cells infiltration into islets. A general observation of pancreas was also done. Twelve Chinchilla-breed female adult rabbits were divided into control (n = 6) and hypothyroid groups (n = 6, methimazole, 0.02% in drinking water for 30 days). After the treatment, rabbits were sacrificed and their pancreas was excised, histologically processed, and stained with Periodic Acid-Schiff (PAS) or Masson's Trichrome techniques. Islets were arbitrarily classified into large, medium, and small ones. The external and internal portions of each islet were also identified. Student-t-test and Mann-Whitney-U test or two-way ANOVAs were used to compare variables between groups. In comparison with control rabbits, hypothyroidism induced a strong infiltration of immune cells and a major presence of collagen and proteoglycans in the interlobular septa. Large islets showed a high vascularization and immune cells infiltration. The present results show that hypothyroidism induces pancreatitis and insulitis. PMID:26175757

  13. Hypothyroidism Affects Vascularization and Promotes Immune Cells Infiltration into Pancreatic Islets of Female Rabbits

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    Julia Rodríguez-Castelán

    2015-01-01

    Full Text Available Thyroidectomy induces pancreatic edema and immune cells infiltration similarly to that observed in pancreatitis. In spite of the controverted effects of hypothyroidism on serum glucose and insulin concentrations, the number and proliferation of Langerhans islet cells as well as the presence of extracellular matrix are affected depending on the islet size. In this study, we evaluated the effect of methimazole-induced hypothyroidism on the vascularization and immune cells infiltration into islets. A general observation of pancreas was also done. Twelve Chinchilla-breed female adult rabbits were divided into control n=6 and hypothyroid groups (n=6, methimazole, 0.02% in drinking water for 30 days. After the treatment, rabbits were sacrificed and their pancreas was excised, histologically processed, and stained with Periodic Acid-Schiff (PAS or Masson’s Trichrome techniques. Islets were arbitrarily classified into large, medium, and small ones. The external and internal portions of each islet were also identified. Student-t-test and Mann-Whitney-U test or two-way ANOVAs were used to compare variables between groups. In comparison with control rabbits, hypothyroidism induced a strong infiltration of immune cells and a major presence of collagen and proteoglycans in the interlobular septa. Large islets showed a high vascularization and immune cells infiltration. The present results show that hypothyroidism induces pancreatitis and insulitis.

  14. Investigation of retinal morphology alterations using spectral domain optical coherence tomography in a mouse model of retinal branch and central retinal vein occlusion.

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    Andreas Ebneter

    Full Text Available Retinal vein occlusion is a leading cause of visual impairment. Experimental models of this condition based on laser photocoagulation of retinal veins have been described and extensively exploited in mammals and larger rodents such as the rat. However, few reports exist on the use of this paradigm in the mouse. The objective of this study was to investigate a model of branch and central retinal vein occlusion in the mouse and characterize in vivo longitudinal retinal morphology alterations using spectral domain optical coherence tomography. Retinal veins were experimentally occluded using laser photocoagulation after intravenous application of Rose Bengal, a photo-activator dye enhancing thrombus formation. Depending on the number of veins occluded, variable amounts of capillary dropout were seen on fluorescein angiography. Vascular endothelial growth factor levels were markedly elevated early and peaked at day one. Retinal thickness measurements with spectral domain optical coherence tomography showed significant swelling (p<0.001 compared to baseline, followed by gradual thinning plateauing two weeks after the experimental intervention (p<0.001. Histological findings at day seven correlated with spectral domain optical coherence tomography imaging. The inner layers were predominantly affected by degeneration with the outer nuclear layer and the photoreceptor outer segments largely preserved. The application of this retinal vein occlusion model in the mouse carries several advantages over its use in other larger species, such as access to a vast range of genetically modified animals. Retinal changes after experimental retinal vein occlusion in this mouse model can be non-invasively quantified by spectral domain optical coherence tomography, and may be used to monitor effects of potential therapeutic interventions.

  15. Astrocytes and Müller cells changes during retinal degeneration in a transgenic rat model of retinitis pigmentosa.

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    Laura eFernández-Sánchez

    2015-12-01

    Full Text Available Purpose: Retinitis pigmentosa includes a group of progressive retinal degenerative diseases that affect the structure and function of photoreceptors. Secondarily to the loss of photoreceptors, there is a reduction in retinal vascularization, which seems to influence the cellular degenerative process. Retinal macroglial cells, astrocytes and Müller cells provide support for retinal neurons and are fundamental for maintaining normal retinal function. The aim of this study was to investigate the evolution of macroglial changes during retinal degeneration in P23H rats. Methods: Homozygous P23H line-3 rats aged from P18 to 18 months were used to study the evolution of the disease, and SD rats were used as controls. Immunolabeling with antibodies against GFAP, vimentin, and transducin were used to visualize macroglial cells and cone photoreceptors. Results: In P23H rats, increased GFAP labeling in Müller cells was observed as an early indicator of retinal gliosis. At 4 and 12 months of age, the apical processes of Müller cells in P23H rats clustered in firework-like structures, which were associated with ring-like shaped areas of cone degeneration in the outer nuclear layer. These structures were not observed at 16 months of age. The number of astrocytes was higher in P23H rats than in the SD matched controls at 4 and 12 months of age, supporting the idea of astrocyte proliferation. As the disease progressed, astrocytes exhibited a deteriorated morphology and marked hypertrophy. The increase in the complexity of the astrocytic processes correlated with greater connexin 43 expression and higher density of connexin 43 immunoreactive puncta within the ganglion cell layer of P23H versus SD rat retinas. Conclusions: In the P23H rat model of retinitis pigmentosa, the loss of photoreceptors triggers major changes in the number and morphology of glial cells affecting the inner retina.

  16. Change of retinal pigment epithelial atrophy after anti-vascular endothelial growth factor treatment in exudative age-related macular degeneration

    Directory of Open Access Journals (Sweden)

    Moosang Kim

    2016-01-01

    Full Text Available Purpose: The study aimed to investigate the quantitative changes of retinal pigment epithelial (RPE atrophy during a 24-month follow-up period of anti-vascular endothelial growth factor (VEGF for exudative age-related macular degeneration (AMD. Materials and Methods: This is a retrospective study. Sixty-five eyes of 62 consecutive patients with naοve exudative AMD who had received treatment with anti-VEGF therapy and followed for more 24 months were enrolled. All patients received three initial monthly injections of anti-VEGF (ranibizumab or bevacizumab, followed by pro re nata or treat-and-extend protocol. Color fundus image, optical coherence tomography, and fundus autofluorescence were evaluated for RPE atrophy. Multiple regression analysis was performed to investigate the predictive factors found during univariate analysis to identify an association with increased RPE atrophic areas. Results: The mean number of anti-VEGF treatments was 9.18. RPE atrophic area was 1.293 ± 1.298 mm 2 at baseline and enlarged to 2.394 ± 1.940 mm 2 after 24 months, which differed significantly (P = 0.001. Multiple regression analysis revealed that larger areas of RPE atrophy at month 4 and larger numbers of anti-VEGF treatments were associated with increased RPE atrophic areas. Conclusions: RPE atrophy progresses in eyes with exudative AMD during anti-VEGF treatment. Larger areas of RPE atrophy at month 4 and larger numbers of anti-VEGF injections were associated with an increased risk of progression of RPE atrophy the following treatment. These findings may be useful to clinicians using intravitreal anti-VEGF for the treatment of exudative AMD, both for selecting an appropriate treatment plan and for predicting the progression of RPE atrophy.

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

    Directory of Open Access Journals (Sweden)

    Park Jongsun

    2009-10-01

    Full Text Available Abstract The aim of this study is to determine the effects of silver nanoparticles (Ag-NP on vascular endothelial growth factor (VEGF-and interleukin-1 beta (IL-1β-induced vascular permeability, and to detect the underlying signaling mechanisms involved in endothelial cells. Porcine retinal endothelial cells (PRECs were exposed to VEGF, IL-1β and Ag-NP at different combinations and endothelial cell permeability was analyzed by measuring the flux of RITC-dextran across the PRECs monolayer. We found that VEGF and IL-1β increase flux of dextran across a PRECs monolayer, and Ag-NP block solute flux induced by both VEGF and IL-1β. To explore the signalling pathway involved VEGF- and IL-1β-induced endothelial alteration, PRECs were treated with Src inhibitor PP2 prior to VEGF and IL-1β treatment, and the effects were recorded. Further, to clarify the possible involvement of the Src pathways in endothelial cell permeability, plasmid encoding dominant negative(DN and constitutively active(CA form of Src kinases were transfected into PRECs, 24 h prior to VEGF and IL-1β exposure and the effects were recorded. Overexpression of DN Src blocked both VEGF-and IL-1β-induced permeability, while overexpression of CA Src rescues the inhibitory action of Ag-NP in the presence or absence of VEGF and IL-1β. Further, an in vitro kinase assay was performed to identify the presence of the Src phosphorylation at Y419. We report that VEGF and IL-1β-stimulate endothelial permeability via Src dependent pathway by increasing the Src phosphorylation and Ag-NP block the VEGF-and IL-1β-induced Src phosphorylation at Y419. These results demonstrate that Ag-NP may inhibit the VEGF-and IL-1β-induced permeability through inactivation of Src kinase pathway and this pathway may represent a potential therapeutic target to inhibit the ocular diseases such as diabetic retinopathy.

  18. Probabilistic retinal vessel segmentation

    Science.gov (United States)

    Wu, Chang-Hua; Agam, Gady

    2007-03-01

    Optic fundus assessment is widely used for diagnosing vascular and non-vascular pathology. Inspection of the retinal vasculature may reveal hypertension, diabetes, arteriosclerosis, cardiovascular disease and stroke. Due to various imaging conditions retinal images may be degraded. Consequently, the enhancement of such images and vessels in them is an important task with direct clinical applications. We propose a novel technique for vessel enhancement in retinal images that is capable of enhancing vessel junctions in addition to linear vessel segments. This is an extension of vessel filters we have previously developed for vessel enhancement in thoracic CT scans. The proposed approach is based on probabilistic models which can discern vessels and junctions. Evaluation shows the proposed filter is better than several known techniques and is comparable to the state of the art when evaluated on a standard dataset. A ridge-based vessel tracking process is applied on the enhanced image to demonstrate the effectiveness of the enhancement filter.

  19. [Retinal and carotid changes in non-alcoholic fatty liver disease].

    Science.gov (United States)

    Baloşeanu, Cristina; Rogoveanu, I; Mocanu, Carmen

    2013-01-01

    This article presents the results of a study on 85 patients with non-alcoholic fatty liver disease (NAFLD). We evaluate the retinal vascular changes using retinal photography and carotid vascular changes, by ultrasounds, occured in this group of patients.

  20. A prospective case-control study to investigate retinal microvascular changes in acute dengue infection.

    Science.gov (United States)

    Tan, Petrina; Lye, David C; Yeo, Tun Kuan; Cheung, Carol Y; Thein, Tun-Linn; Wong, Joshua G; Agrawal, Rupesh; Li, Ling-Jun; Wong, Tien-Yin; Gan, Victor C; Leo, Yee-Sin; Teoh, Stephen C

    2015-01-01

    Dengue infection can affect the microcirculation by direct viral infection or activation of inflammation. We aimed to determine whether measured retinal vascular parameters were associated with acute dengue infection. Patients with acute dengue were recruited from Communicable Diseases Center, Singapore and age-gender-ethnicity matched healthy controls were selected from a population-based study. Retinal photographs were taken on recruitment and convalescence. A spectrum of quantitative retinal microvascular parameters (retinal vascular caliber, fractal dimension, tortuosity and branching angle) was measured using a semi-automated computer-based program. (Singapore I Vessel Assessment, version 3.0). We included 62 dengue patients and 127 controls. Dengue cases were more likely to have wider retinal arteriolar and venular calibers (158.3 μm vs 144.3 μm, p dengue coincided with decrease in retinal vascular calibers and venular fractal dimension. Dengue patients have altered microvascular network in the retina; these changes may reflect pathophysiological processes in the immune system.

  1. The genetic background affects the vascular response in T-type calcium channels 3.2 deficient mice

    DEFF Research Database (Denmark)

    Svenningsen, Per; Hansen, Pernille B L

    2016-01-01

    Voltage-gated calcium channels (Cav ) are important regulators of vascular tone and are attractive targets for pharmacological treatment of hypertension. The clinical used calcium blockers are often not selective for one channel but affect several types of calcium channels (Hansen 2015). L...

  2. Pre-Analytical Parameters Affecting Vascular Endothelial Growth Factor Measurement in Plasma: Identifying Confounders.

    Directory of Open Access Journals (Sweden)

    Johanna M Walz

    Full Text Available Vascular endothelial growth factor-A (VEGF-A is intensively investigated in various medical fields. However, comparing VEGF-A measurements is difficult because sample acquisition and pre-analytic procedures differ between studies. We therefore investigated which variables act as confounders of VEGF-A measurements.Following a standardized protocol, blood was taken at three clinical sites from six healthy participants (one male and one female participant at each center twice one week apart. The following pre-analytical parameters were varied in order to analyze their impact on VEGF-A measurements: analyzing center, anticoagulant (EDTA vs. PECT / CTAD, cannula (butterfly vs. neonatal, type of centrifuge (swing-out vs. fixed-angle, time before and after centrifugation, filling level (completely filled vs. half-filled tubes and analyzing method (ELISA vs. multiplex bead array. Additionally, intrapersonal variations over time and sex differences were explored. Statistical analysis was performed using a linear regression model.The following parameters were identified as statistically significant independent confounders of VEGF-A measurements: analyzing center, anticoagulant, centrifuge, analyzing method and sex of the proband. The following parameters were no significant confounders in our data set: intrapersonal variation over one week, cannula, time before and after centrifugation and filling level of collection tubes.VEGF-A measurement results can be affected significantly by the identified pre-analytical parameters. We recommend the use of CTAD anticoagulant, a standardized type of centrifuge and one central laboratory using the same analyzing method for all samples.

  3. Retinal vessel diameter changes induced by transient high perfusion pressure

    Institute of Scientific and Technical Information of China (English)

    Yin-Ying; Zhao; Ping-Jun; Chang; Fang; Yu; Yun-E; Zhao

    2014-01-01

    ·AIM: To investigate the effects of transient high perfusion pressure on the retinal vessel diameter and retinal ganglion cells.·METHODS: The animals were divided into four groups according to different infusion pressure and infusion time(60 mm Hg-3min, 60 mm Hg-5min, 100 mm Hg-3min, 100 mm Hg-5min). Each group consisted of six rabbits. The left eye was used as the experimental eye and the right as a control. Retinal vascular diameters were evaluated before, during infusion, immediately after infusion, 5min, 10 min and 30 min after infusion based on the fundus photographs. Blood pressure was monitored during infusion. The eyes were removed after 24 h.Damage to retinal ganglion cell(RGC) was analyzed by histology.·RESULTS: Retina became whiten and papilla optic was pale during perfusion. Measurements showed significant decrease in retinal artery and vein diameter during perfusion in all of the four groups at the proximal of the edge of the optic disc. The changes were significant in the 100 mm Hg-3min group and 100 mm Hg-5min group compared with 60 mm Hg-3min group(P 1=0.025, P 2=0.000).The diameters in all the groups recovered completely after 30 min of reperfusion. The number of RGC)showed no significant changes at the IOP in 100 mm Hg with5 min compared with contralateral untreated eye(P >0.05).·CONCLUSION: Transient fluctuations during infusion lead to temporal changes of retinal vessels, which could affect the retinal blood circulation. The RGCs were not affected by this transient fluctuation. Further studies are necessary to evaluate the effect of pressure during realtime phacoemusification on retinal blood circulation.

  4. Inhibition of vascular endothelial growth factor gene expression by T7-siRNAs in cultured human retinal pigment epithelial cells

    Institute of Scientific and Technical Information of China (English)

    LI Guang-yu; FAN Bin; WU Ya-zhen; WANG Xin-rui; WANG Yao-hui; WU Jia-xiang

    2005-01-01

    Background Retinal pigment epithelial (RPE) cells play an important role in the occurrence of choroidal neovascularization (CNV). Vascular endothelial growth factor (VEGF) as a positive regulatory growth factor is produced by the RPE in an autocrine or paracrine manner, promoting CNV development. Duplexes of 21 nt RNAs, known as short interfering RNAs (siRNAs), efficiently inhibit gene expression by RNA interference when introduced into mammalian cells. We searched for an efficient siRNA to interfere with VEGF expression in RPE cells and shed light on the treatment of CNV.Methods Human primary RPE (hRPE) cells were cultured and identified. Three pairs of siRNAs were designed according to the sequence of VEGF 1-5 extrons and synthesized by T7 RNA polymerase transcription in vitro. To evaluate the inhibitory activity of T7-siRNAs, hRPE cells were transfected via siPORT Amine. The interfering effect of T7-siRNAs in hRPE cells was examined by semiquantitative reverse transcription-polymerase chain reaction and immunofluorescence. Results Three pairs of T7-siRNAs synthesized by in vitro transcription with T7 RNA polymerase suppressed VEGF gene expression with efficiency from 65% to 90%. T7-siRNA (B), targeted region at 207 nt to 228 nt and double stranded for 21 nt with 2 nt UU 3' overhangs, was the most effective sequence tested for inhibition of VEGF expression in hRPE cells. Compared with nontransfected cells, the mean fluorescence in hRPE cells transfected with T7-sRNAs was significantly less (P<0.01). siRNA with a single-base mismatch and ssRNA(+) did not show suppressing effect. Furthermore, it was found that siRNAs had a dose dependent inhibitory effect (5 to 10 pmol).Conclusion T7-siRNA can effectively and specifically suppress VEGF expression in hRPE cells and may be a new way to treat CNV.

  5. Prevention of vascular calcification with bisphosphonates without affecting bone mineralization: a new challenge?

    Science.gov (United States)

    Neven, Ellen G; De Broe, Marc E; D'Haese, Patrick C

    2009-03-01

    Arterial calcification has been found to coexist with bone loss. Bisphosphonates, used as standard therapy for osteoporosis, inhibit experimentally induced vascular calcification, offering perspectives for the treatment of vascular calcification in renal failure patients. However, Lomashvili et al. report that the doses of etidronate and pamidronate that are effective in attenuating aortic calcification also decrease bone formation and mineralization in uremic rats, limiting their therapeutic use as anticalcifying agents.

  6. Luminal epithelium in endometrial fragments affects their vascularization, growth and morphological development into endometriosis-like lesions in mice

    Directory of Open Access Journals (Sweden)

    Dilu Feng

    2014-02-01

    Full Text Available In endometriosis research, endometriosis-like lesions are usually induced in rodents by transplantation of isolated endometrial tissue fragments to ectopic sites. In the present study, we investigated whether this approach is affected by the cellular composition of the grafts. For this purpose, endometrial tissue fragments covered with luminal epithelium (LE+ and without luminal epithelium (LE− were transplanted from transgenic green-fluorescent-protein-positive (GFP+ donor mice into the dorsal skinfold chamber of GFP− wild-type recipient animals to analyze their vascularization, growth and morphology by means of repetitive intravital fluorescence microscopy, histology and immunohistochemistry during a 14-day observation period. LE− fragments developed into typical endometriosis-like lesions with cyst-like dilated endometrial glands and a well-vascularized endometrial stroma. In contrast, LE+ fragments exhibited a polypoid morphology and a significantly reduced blood perfusion after engraftment, because the luminal epithelium prevented the vascular interconnection with the microvasculature of the surrounding host tissue. This was associated with a markedly decreased growth rate of LE+ lesions compared with LE− lesions. In addition, we found that many GFP+ microvessels grew outside the LE− lesions and developed interconnections to the host microvasculature, indicating that inosculation is an important mechanism in the vascularization process of endometriosis-like lesions. Our findings demonstrate that the luminal epithelium crucially affects the vascularization, growth and morphology of endometriosis-like lesions. Therefore, it is of major importance to standardize the cellular composition of endometrial grafts in order to increase the validity and reliability of pre-clinical rodent studies in endometriosis research.

  7. Luminal epithelium in endometrial fragments affects their vascularization, growth and morphological development into endometriosis-like lesions in mice.

    Science.gov (United States)

    Feng, Dilu; Menger, Michael D; Wang, Hongbo; Laschke, Matthias W

    2014-02-01

    In endometriosis research, endometriosis-like lesions are usually induced in rodents by transplantation of isolated endometrial tissue fragments to ectopic sites. In the present study, we investigated whether this approach is affected by the cellular composition of the grafts. For this purpose, endometrial tissue fragments covered with luminal epithelium (LE(+)) and without luminal epithelium (LE(-)) were transplanted from transgenic green-fluorescent-protein-positive (GFP(+)) donor mice into the dorsal skinfold chamber of GFP(-) wild-type recipient animals to analyze their vascularization, growth and morphology by means of repetitive intravital fluorescence microscopy, histology and immunohistochemistry during a 14-day observation period. LE(-) fragments developed into typical endometriosis-like lesions with cyst-like dilated endometrial glands and a well-vascularized endometrial stroma. In contrast, LE(+) fragments exhibited a polypoid morphology and a significantly reduced blood perfusion after engraftment, because the luminal epithelium prevented the vascular interconnection with the microvasculature of the surrounding host tissue. This was associated with a markedly decreased growth rate of LE(+) lesions compared with LE(-) lesions. In addition, we found that many GFP(+) microvessels grew outside the LE(-) lesions and developed interconnections to the host microvasculature, indicating that inosculation is an important mechanism in the vascularization process of endometriosis-like lesions. Our findings demonstrate that the luminal epithelium crucially affects the vascularization, growth and morphology of endometriosis-like lesions. Therefore, it is of major importance to standardize the cellular composition of endometrial grafts in order to increase the validity and reliability of pre-clinical rodent studies in endometriosis research.

  8. Activation tagging of the two closely linked genes LEP and VAS independently affects vascular cell number

    DEFF Research Database (Denmark)

    van der Graaff, Eric; Hooykaas, Paul J J; Keller, Beat

    2002-01-01

    The complex dominant Arabidopsis thaliana mutant lettuce (let) shows the conversion of the leaf petiole into a leaf blade caused by an ectopic leaf blade formation. This is the result of the activation tagging of the LEAFY PETIOLE (LEP) gene encoding an AP2/EREBP-like transcription factor. Here, we...... report that in addition to this leafy petiole phenotype, the size of the vascular bundles is increased in all aerial organs in let as a result of an increase in the number of xylem, phloem (pro)cambial and pericycle cells. This vascular phenotype is caused by activation tagging of the two genes VASCULAR...... TISSUE SIZE (VAS) and LEP. These genes are closely linked and arranged in tandem. Activation tagging of LEP only caused a specific increase in the number of xylem cells. This increased xylem cell number, together with the ectopic leaf blade formation, indicates that LEP functions as a cell division...

  9. A residue substitution near the beta-ionone ring of the retinal affects the M substates of bacteriorhodopsin

    Science.gov (United States)

    Varo, G.; Zimanyi, L.; Chang, M.; Ni, B.; Needleman, R.; Lanyi, J. K.

    1992-01-01

    The switch in the bacteriorhodopsin photocycle, which reorients access of the retinal Schiff base from the extracellular to the cytoplasmic side, was suggested to be an M1----M2 reaction (Varo and Lanyi. 1991. Biochemistry. 30:5008-5015, 5016-5022). Thus, in this light-driven proton pump it is the interconversion of proposed M substates that gives direction to the transport. We find that in monomeric, although not purple membrane-lattice immobilized, D115N bacteriorhodopsin, the absorption maximum of M changes during the photocycle: in the time domain between its rise and decay it shifts 15 nm to the blue relative to the spectrum at earlier times. This large shift strongly supports the existence of two M substates. Since D115 is located near the beta-ionone ring of the retinal, the result raises questions about the possible involvement of the retinal chain or protein residues as far away as 10 A from the Schiff base in the mechanism of the switching reaction.

  10. Pattern of omega-3 polyunsaturated fatty acid intake and fish consumption and retinal vascular caliber in children and adolescents: A cohort study

    Science.gov (United States)

    Moshtaghian, Hanieh; Flood, Victoria M.; Louie, Jimmy C. Y.; Liew, Gerald; Burlutsky, George; Mitchell, Paul

    2017-01-01

    We aimed to investigate whether fish and long chain omega-3 polyunsaturated fatty acid (LCn-3 PUFA) consumption changed appreciably during adolescence. We also assessed whether these dietary variables are associated with retinal microvascular signs (possible markers of future cardiovascular disease risk). 633 children had dietary data at ages 12 and 17. Fish and LCn-3 PUFA [eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA)] intake was assessed by a food frequency questionnaire. Retinal vessel caliber was quantified from digital photographs using computer software. Mean energy-adjusted intakes (mg/day) of total LCn-3 PUFA, EPA, and DHA at age 12 were 297.1±261.1; 102.5±106.9; and 129.7±137.7, respectively; and this increased significantly at age 17 to: 347.0±324.0 (p<0.0001); 122.5±132.7 (p = 0.0001); and 160.3±171.4 (p <0.0001), respectively. Increasing quartiles of LCn-3PUFA intake were associated with widening of mean retinal arteriolar caliber among 17-year old girls ~3.9 μm (multivariable-adjusted P-trend = 0.001). Girls who consumed ≥2 serves of fish/week versus those who did not had ~2.1 μm wider retinal arterioles (p = 0.03). No associations were observed among boys or with retinal venules. Mean dietary intakes of LCn-3 PUFA increased during adolescence, but are still below recommended levels of consumption. These results suggest that LCn-3 PUFA and fish intake might have a beneficial influence. PMID:28192538

  11. An analysis of vascular surgery in elderly patients to determine whether age affects treatment strategy.

    LENUS (Irish Health Repository)

    O'Brien, G

    2012-03-01

    The incidence of arterial disease increases with age. Increasing life expectancy in the western world will intensify demands on vascular surgeons with regard to increasing caseload, expanding patient selection criteria, and more complex and minimally-invasive treatment options. We analysed our arterial cases over the past 31 years (n = 6,144) and compared our methods of intervention and complication rates in the elderly population (>75) with the younger cohort, in order to determine whether age should influence our management strategies.

  12. Novel Vascular Malformation in an Affected Newborn with Deletion Del(4)(q31.3)

    OpenAIRE

    Norma Elena de León Ojeda; Michel Soriano-Torres; Cabrera, Mercedes J.; Dunia Bárbara Benítez Ramos

    2012-01-01

    We report on a newborn male patient with a terminal deletion in the long arm of the chromosome 4 with a congenital heart defect unreported before in association with this syndrome. The patient had multiple congenital anomalies including a pointed duplicated fingernail, low set posteriorly rotated ears, large anterior fontanel, micrognathia, glabellar capillary vascular malformation, and Interrupted Aortic Arch type C. The patient died due to multiple congenital malformations; a peripheral chr...

  13. Plasma inflammatory and vascular homeostasis biomarkers increase during human pregnancy but are not affected by oily fish intake.

    Science.gov (United States)

    García-Rodríguez, Cruz E; Olza, Josune; Aguilera, Concepción M; Mesa, María D; Miles, Elizabeth A; Noakes, Paul S; Vlachava, Maria; Kremmyda, Lefkothea-Stella; Diaper, Norma D; Godfrey, Keith M; Calder, Philip C; Gil, Angel

    2012-07-01

    The Salmon in Pregnancy Study investigated whether the increased consumption of (n-3) long-chain PUFA (LC-PUFA) from farmed Atlantic salmon affects immune function during pregnancy and atopic disease in neonates compared with a habitual diet low in oily fish. In this context, because the ingestion of (n-3) LC-PUFA may lower the concentrations of inflammatory biomarkers, we investigated whether the consumption of oily fish affects the levels of inflammatory cytokines and vascular adhesion factors during pregnancy. Pregnant women (n = 123) were randomly assigned to continue their habitual diet (control group, n = 61), which was low in oily fish, or to consume two 150-g salmon portions/wk (salmon group, n = 62; providing 3.45 g EPA plus DHA) from 20 wk of gestation until delivery. Plasma inflammatory cytokines and vascular adhesion factors were measured in maternal plasma samples. Inflammatory biomarkers, including IL-8, hepatocyte growth factor, and monocyte chemotactic protein, increased over the course of pregnancy (P pregnancy progressed (P pregnancy, they are not affected by the increased intake of farmed salmon.

  14. Optical Coherence Tomography Angiography in Retinal Diseases.

    Science.gov (United States)

    Chalam, K V; Sambhav, Kumar

    2016-01-01

    Optical coherence tomography angiography (OCTA) is a new, non-invasive imaging system that generates volumetric data of retinal and choroidal layers. It has the ability to show both structural and blood flow information. Split-spectrum amplitude-decorrelation angiography (SSADA) algorithm (a vital component of OCTA software) helps to decrease the signal to noise ratio of flow detection thus enhancing visualization of retinal vasculature using motion contrast. Published studies describe potential efficacy for OCTA in the evaluation of common ophthalmologic diseases such as diabetic retinopathy, age related macular degeneration (AMD), retinal vascular occlusions and sickle cell disease. OCTA provides a detailed view of the retinal vasculature, which allows accurate delineation of microvascular abnormalities in diabetic eyes and vascular occlusions. It helps quantify vascular compromise depending upon the severity of diabetic retinopathy. OCTA can also elucidate the presence of choroidal neovascularization (CNV) in wet AMD. In this paper, we review the knowledge, available in English language publications regarding OCTA, and compare it with the conventional angiographic standard, fluorescein angiography (FA). Finally, we summarize its potential applications to retinal vascular diseases. Its current limitations include a relatively small field of view, inability to show leakage, and tendency for image artifacts. Further larger studies will define OCTA's utility in clinical settings and establish if the technology may offer a non-invasive option of visualizing the retinal vasculature, enabling us to decrease morbidity through early detection and intervention in retinal diseases.

  15. Optical coherence tomography angiography in retinal diseases

    Directory of Open Access Journals (Sweden)

    K V Chalam

    2016-01-01

    Full Text Available Optical coherence tomography angiography (OCTA is a new, non-invasive imaging system that generates volumetric data of retinal and choroidal layers. It has the ability to show both structural and blood flow information. Split-spectrum amplitude-decorrelation angiography (SSADA algorithm (a vital component of OCTA software helps to decrease the signal to noise ratio of flow detection thus enhancing visualization of retinal vasculature using motion contrast. Published studies describe potential efficacy for OCTA in the evaluation of common ophthalmologic diseases such as diabetic retinopathy, age related macular degeneration (AMD, retinal vascular occlusions and sickle cell disease. OCTA provides a detailed view of the retinal vasculature, which allows accurate delineation of microvascular abnormalities in diabetic eyes and vascular occlusions. It helps quantify vascular compromise depending upon the severity of diabetic retinopathy. OCTA can also elucidate the presence of choroidal neovascularization (CNV in wet AMD. In this paper, we review the knowledge, available in English language publications regarding OCTA, and compare it with the conventional angiographic standard, fluorescein angiography (FA. Finally, we summarize its potential applications to retinal vascular diseases. Its current limitations include a relatively small field of view, inability to show leakage, and tendency for image artifacts. Further larger studies will define OCTA's utility in clinical settings and establish if the technology may offer a non-invasive option of visualizing the retinal vasculature, enabling us to decrease morbidity through early detection and intervention in retinal diseases.

  16. Retinal Detachment in Preeclampsia

    Directory of Open Access Journals (Sweden)

    Prado Renata Silva do

    2002-01-01

    Full Text Available Preeclampsia is an obstetric disease of unknown cause that affects approximately 5% of pregnant women. The visual system may be affected with variable intensity, being the retinal detachment a rare complication. The retinal detachment in preeclampsia is usually bilateral and serous, and its pathogenesis is related to the choroidal ischemia secondary to an intense arteriolar vasospasm. The majority of patients have complete recovery of vision with clinical management, and surgery is unnecessary. This is a case report of a 27 year old patient who developed the severe form of preeclampsia on her first pregnancy. She had progressive blurred vision, until she could see only shadows. Ophthalmic examination diagnosed spread and bilateral retinal detachment. With blood pressure control at postpartum, the patient had her retina reattached, and recovery of vision.

  17. Automatic Vessel Segmentation on Retinal Images

    Institute of Scientific and Technical Information of China (English)

    Chun-Yuan Yu; Chia-Jen Chang; Yen-Ju Yao; Shyr-Shen Yu

    2014-01-01

    Several features of retinal vessels can be used to monitor the progression of diseases. Changes in vascular structures, for example, vessel caliber, branching angle, and tortuosity, are portents of many diseases such as diabetic retinopathy and arterial hyper-tension. This paper proposes an automatic retinal vessel segmentation method based on morphological closing and multi-scale line detection. First, an illumination correction is performed on the green band retinal image. Next, the morphological closing and subtraction processing are applied to obtain the crude retinal vessel image. Then, the multi-scale line detection is used to fine the vessel image. Finally, the binary vasculature is extracted by the Otsu algorithm. In this paper, for improving the drawbacks of multi-scale line detection, only the line detectors at 4 scales are used. The experimental results show that the accuracy is 0.939 for DRIVE (digital retinal images for vessel extraction) retinal database, which is much better than other methods.

  18. Driving with Central Visual Field Loss II: How Scotomas above or below the Preferred Retinal Locus (PRL Affect Hazard Detection in a Driving Simulator.

    Directory of Open Access Journals (Sweden)

    P Matthew Bronstad

    Full Text Available We determined whether binocular central scotomas above or below the preferred retinal locus affect detection of hazards (pedestrians approaching from the side. Seven participants with central field loss (CFL, and seven age-and sex-matched controls with normal vision (NV, each completed two sessions of 5 test drives (each approximately 10 minutes long in a driving simulator. Participants pressed the horn when detecting pedestrians that appeared at one of four eccentricities (-14°, -4°, left, 4°, or 14°, right, relative to car heading. Pedestrians walked or ran towards the travel lane on a collision course with the participant's vehicle, thus remaining in the same area of the visual field, assuming participant's steady forward gaze down the travel lane. Detection rates were nearly 100% for all participants. CFL participant reaction times were longer (median 2.27s, 95% CI 2.13 to 2.47 than NVs (median 1.17s, 95%CI 1.10 to 2.13; difference p<0.01, and CFL participants would have been unable to stop for 21% of pedestrians, compared with 3% for NV, p<0.001. Although the scotomas were not expected to obscure pedestrian hazards, gaze tracking revealed that scotomas did sometimes interfere with detection; late reactions usually occurred when pedestrians were entirely or partially obscured by the scotoma (time obscured correlated with reaction times, r = 0.57, p<0.001. We previously showed that scotomas lateral to the preferred retinal locus delay reaction times to a greater extent; however, taken together, the results of our studies suggest that any binocular CFL might negatively impact timely hazard detection while driving and should be a consideration when evaluating vision for driving.

  19. A Single Nucleotide Polymorphism in the Bax Gene Promoter Affects Transcription and Influences Retinal Ganglion Cell Death

    Directory of Open Access Journals (Sweden)

    Sheila J Semaan

    2010-03-01

    Full Text Available Pro-apoptotic Bax is essential for RGC (retinal ganglion cell death. Gene dosage experiments in mice, yielding a single wild-type Bax allele, indicated that genetic background was able to influence the cell death phenotype. DBA/2J Bax+/− mice exhibited complete resistance to nerve damage after 2 weeks (similar to Bax −/− mice, but 129B6 Bax+/− mice exhibited significant cell loss (similar to wild-type mice. The different cell death phenotype was associated with the level of Bax expression, where 129B6 neurons had twice the level of endogenous Bax mRNA and protein as DBA/2J neurons. Sequence analysis of the Bax promoters between these strains revealed a single nucleotide polymorphism (T129B6 to CDBA/2J at position −515. A 1.5- to 2.5-fold increase in transcriptional activity was observed from the 129B6 promoter in transient transfection assays in a variety of cell types, including RGC5 cells derived from rat RGCs. Since this polymorphism occurred in a p53 half-site, we investigated the requirement of p53 for the differential transcriptional activity. Differential transcriptional activity from either 129B6 or DBA/2J Bax promoters were unaffected in p53−/− cells, and addition of exogenous p53 had no further effect on this difference, thus a role for p53 was excluded. Competitive electrophoretic mobility-shift assays identified two DNA-protein complexes that interacted with the polymorphic region. Those forming Complex 1 bound with higher affinity to the 129B6 polymorphic site, suggesting that these proteins probably comprised a transcriptional activator complex. These studies implicated quantitative expression of the Bax gene as playing a possible role in neuronal susceptibility to damaging stimuli.

  20. Optical modulation of transgene expression in retinal pigment epithelium

    Science.gov (United States)

    Palanker, D.; Lavinsky, D.; Chalberg, T.; Mandel, Y.; Huie, P.; Dalal, R.; Marmor, M.

    2013-03-01

    Over a million people in US alone are visually impaired due to the neovascular form of age-related macular degeneration (AMD). The current treatment is monthly intravitreal injections of a protein which inhibits Vascular Endothelial Growth Factor, thereby slowing progression of the disease. The immense financial and logistical burden of millions of intravitreal injections signifies an urgent need to develop more long-lasting and cost-effective treatments for this and other retinal diseases. Viral transfection of ocular cells allows creation of a "biofactory" that secretes therapeutic proteins. This technique has been proven successful in non-human primates, and is now being evaluated in clinical trials for wet AMD. However, there is a critical need to down-regulate gene expression in the case of total resolution of retinal condition, or if patient has adverse reaction to the trans-gene products. The site for genetic therapy of AMD and many other retinal diseases is the retinal pigment epithelium (RPE). We developed and tested in pigmented rabbits, an optical method to down-regulate transgene expression in RPE following vector delivery, without retinal damage. Microsecond exposures produced by a rapidly scanning laser vaporize melanosomes and destroy a predetermined fraction of the RPE cells selectively. RPE continuity is restored within days by migration and proliferation of adjacent RPE, but since the transgene is not integrated into the nucleus it is not replicated. Thus, the decrease in transgene expression can be precisely determined by the laser pattern density and further reduced by repeated treatment without affecting retinal structure and function.

  1. Presumed toxoplasmic central retinal artery occlusion and multifocal retinitis with perivascular sheathing

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    Arai H

    2014-04-01

    Full Text Available Haruka Arai,1 Tsutomu Sakai,1 Kiichiro Okano,1 Ranko Aoyagi,1 Ayano Imai,2 Hiroshi Takase,2 Manabu Mochizuki,2 Hiroshi Tsuneoka11Department of Ophthalmology, Jikei University School of Medicine, Tokyo, Japan; 2Department of Ophthalmology and Visual Science, Tokyo Medical and Dental University, Tokyo, JapanAbstract: Central retinal artery occlusion (CRAO and multifocal retinitis with perivascular sheathing are rare in ocular toxoplasmosis. We report a case of toxoplasmic CRAO and multifocal retinitis with perivascular sheathing. A healthy 83-year-old male developed left panuveitis. Funduscopic examination of the left eye showed a swollen optic disc and sheathing of the retinal artery with a dense vitreous haze and a white retinal lesion. Serum anti-toxoplasma antibodies were positive in a latex agglutination assay. Vitrectomy was performed to improve visualization of the retinal lesions and for examination of causative microorganisms. A postoperative fundus examination revealed CRAO with optic disc involvement and multifocal retinitis with perivascular sheathing. Qualitative multiplex polymerase chain reaction detected the Toxoplasma gondii B1 gene in ocular fluid from both the aqueous and vitreous humor. The presumed diagnosis of ocular toxoplasmosis was made and treatment was started with prednisone and acetylspiramycin with subsequent improvement. Two months later, the patient developed active retinochoroiditis in the left eye. After 6 weeks of anti-toxoplasma therapy, the disease involuted. Retinal vascular occlusions and multifocal retinitis with perivascular sheathing are rare in toxoplasmosis. This is the first case report of toxoplasmic CRAO and multifocal retinitis with perivascular sheathing. The diagnosis of ocular toxoplasmosis should be considered in patients with retinal artery occlusions and multifocal retinitis with perivascular sheathing associated with inflammation.Keywords: ocular toxoplasmosis, toxoplasma retinochoroiditis

  2. Cytomegalovirus retinitis associated with acquired immunodeficiency syndrome

    Institute of Scientific and Technical Information of China (English)

    GENG Shuang; YE Jun-jie; ZHAO Jia-liang; LI Tai-sheng; HAN Yang

    2011-01-01

    Background Cytomegalovirus (CMV) retinitis is the most severe intraocular complication that results in total retinal destruction and loss of visual acuity in patients with acquired immunodeficiency syndrome (AIDS). This study aimed to investigate the fundus characteristics, systemic manifestations and therapeutic outcomes of CMV retinitis associated with AIDS.Methods It was a retrospective case series. CMV retinitis was present in 39 eyes (25 patients). Best corrected visual acuities, anterior segment, fundus features, fundus fluorescence angiography (FFA) and CD4+ T-lymphocyte counts of the patients with CMV retinitis associated with AIDS were analyzed. Intravitreal injections of ganciclovir (400 μg) were performed in 4 eyes (2 patients).Results Retinal vasculitis, dense, full-thickness, yellow-white lesions along vascular distribution with irregular granules at the border, and hemorrhage on the retinal surface were present in 28 eyes. The vitreous was clear or mildly opaque.Late stage of the retinopathy was demonstrated in 8 eyes characterized as atrophic retina, sclerotic and attenuated vessels, retinal pigment epithelium (RPE) atrophy, and optic nerve atrophy. Retinal detachment was found in 3 eyes. The average CD4+ T-lymphocyte count in peripheral blood of the patients with CMV retinitis was (30.6±25.3) ×106/L (range,(0-85) × 106/L). After intravitreal injections of ganciclovir, visual acuity was improved and fundus lesions regressed.Conclusions CMV retinitis is the most severe and the most common intraocular complication in patients with AIDS. For the patients with yellow-white retinal lesions, hemorrhage and retinal vasculitis without clear cause, human immunodeficiency virus (HIV) serology should be performed. Routine eye examination is also indicated in HIV positive patients.

  3. CLINICAL STUDY OF RETINAL VEIN OCCLUSIONS AND MANAGEMENT

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    Satyavathi

    2015-01-01

    Full Text Available Retinal vein occlusion is the most common retinal occlusive disorder encountered by Ophthalmologists and is usually associated with a variable amount of visual loss. This is the second most common retinal vascular disease next to diabetic retinopathy. Liebreich initially described dramatic obstruction of veins as retinal apoplexy. Leber ( 1 (1877 reported the first case of BRVO and called it Hem orrhagic retinitis. RVO most commonly affects the venous blood supply of the entire retina (CRVO or a quadrant drained by one of the branches (BRVO or less commonly the superior or inferior half of the retina alone is affected (HCRVO. For discussion and management purpose RVO is broadly classified into six clinical entities includes (1 Non - ischemic CRVO (2 Ischemic CRVO (3 Non ischemic HCRVO (4Ischemic HCRVO (5 Major BRVO (6Macular BRVO. So much of confusion still exists regarding its natural histo ry, degree of severity, management and its progression. The clinical study of RVO is taken up mainly with a view to study the importance of systemic risk factors in etiopathogenisis of RVO, to study the clinical features and effectiveness of treatment in m odification of the natural course and complications of RVO. Depending on type of venous occlusion patient may present with loss of central vision frequently noticed on waking up in the morning, or field contraction, erythropsia, floates, black spots. Episo des of amaurosis fugax lasts for minutes to hours may be present. There may be metamor - phopsia. Signs of decreased visual acuty, RAPD, visual field defects are observed. Fundus picture shows Retinal hemorrhages distributed based on type of venous occlusion . In ischemic CRVO the picture shows “berries on a twig”. Various sequel & complications include macular edema, anterior segment and retinal neovascularisation, vitreous hemorrhage, retinal detachment may be encountered. Various risk factors include Hypert ension, Diabetes, Hyper lipidemia, IHD

  4. Affecting of aquatic vascular plant Lemna minor by cisplatin revealed by voltammetry.

    Science.gov (United States)

    Supalkova, Veronika; Beklova, Miroslava; Baloun, Jiri; Singer, Christoph; Sures, Bernd; Adam, Vojtech; Huska, Dalibor; Pikula, Jiri; Rauscherova, Libuse; Havel, Ladislav; Zehnalek, Josef; Kizek, Rene

    2008-02-01

    Within the context of application of platinum derivates based effective cytostatics, we can suppose that these risk metals can get into aquatic ecosystems where they can show biologic availability for food chain. In the present work we report on investigation of affecting of duckweed (Lemna minor) by various doses of cisplatin (0, 5, 10, 20, 40, 80 and 160 microM) for 4 days. The toxic influence of cisplatin was evaluated on the basis of growth inhibition expressed as number of leaves, growth rate, and total amount of biomass. The result value of 96hEC50, calculated from growth inhibition with comparison of growth rates, was 6.93 microM. Moreover we aimed on determination of cisplatin content using differential pulse voltammetry. The highest content of cisplatin (320 ng g(-1) of fresh weight) was determined in plants treated by 80 microM at the second day of treatment. Plants protect themselves against heavy metals by means of synthesis of cysteine-rich peptides such as glutathione and phytochelatins. Thus thiol determination in the treated plants by means of Brdicka reaction followed. The marked increase in thiol concentration detected is associated with defence reaction of the plant against stress caused by cisplatin.

  5. Driving with Central Visual Field Loss II: How Scotomas above or below the Preferred Retinal Locus (PRL) Affect Hazard Detection in a Driving Simulator.

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    Bronstad, P Matthew; Albu, Amanda; Bowers, Alex R; Goldstein, Robert; Peli, Eli

    2015-01-01

    We determined whether binocular central scotomas above or below the preferred retinal locus affect detection of hazards (pedestrians) approaching from the side. Seven participants with central field loss (CFL), and seven age-and sex-matched controls with normal vision (NV), each completed two sessions of 5 test drives (each approximately 10 minutes long) in a driving simulator. Participants pressed the horn when detecting pedestrians that appeared at one of four eccentricities (-14°, -4°, left, 4°, or 14°, right, relative to car heading). Pedestrians walked or ran towards the travel lane on a collision course with the participant's vehicle, thus remaining in the same area of the visual field, assuming participant's steady forward gaze down the travel lane. Detection rates were nearly 100% for all participants. CFL participant reaction times were longer (median 2.27s, 95% CI 2.13 to 2.47) than NVs (median 1.17s, 95%CI 1.10 to 2.13; difference pretinal locus delay reaction times to a greater extent; however, taken together, the results of our studies suggest that any binocular CFL might negatively impact timely hazard detection while driving and should be a consideration when evaluating vision for driving.

  6. Retinitis pigmentosa

    NARCIS (Netherlands)

    Hartong, Dyonne T.; Berson, Eliot L.; Dryja, Thaddeus P.

    2006-01-01

    Hereditary degenerations of the human retina are genetically heterogeneous, with well over 100 genes implicated so far. This Seminar focuses on the subset of diseases called retinitis pigmentosa, in which patients typically lose night vision in adolescence, side vision in young adulthood, and centra

  7. Retinitis pigmentosa

    Directory of Open Access Journals (Sweden)

    Hamel Christian

    2006-10-01

    Full Text Available Abstract Retinitis pigmentosa (RP is an inherited retinal dystrophy caused by the loss of photoreceptors and characterized by retinal pigment deposits visible on fundus examination. Prevalence of non syndromic RP is approximately 1/4,000. The most common form of RP is a rod-cone dystrophy, in which the first symptom is night blindness, followed by the progressive loss in the peripheral visual field in daylight, and eventually leading to blindness after several decades. Some extreme cases may have a rapid evolution over two decades or a slow progression that never leads to blindness. In some cases, the clinical presentation is a cone-rod dystrophy, in which the decrease in visual acuity predominates over the visual field loss. RP is usually non syndromic but there are also many syndromic forms, the most frequent being Usher syndrome. To date, 45 causative genes/loci have been identified in non syndromic RP (for the autosomal dominant, autosomal recessive, X-linked, and digenic forms. Clinical diagnosis is based on the presence of night blindness and peripheral visual field defects, lesions in the fundus, hypovolted electroretinogram traces, and progressive worsening of these signs. Molecular diagnosis can be made for some genes, but is not usually performed due to the tremendous genetic heterogeneity of the disease. Genetic counseling is always advised. Currently, there is no therapy that stops the evolution of the disease or restores the vision, so the visual prognosis is poor. The therapeutic approach is restricted to slowing down the degenerative process by sunlight protection and vitaminotherapy, treating the complications (cataract and macular edema, and helping patients to cope with the social and psychological impact of blindness. However, new therapeutic strategies are emerging from intensive research (gene therapy, neuroprotection, retinal prosthesis.

  8. Experimental Study of 103Pd Stent Affecting Dynamic Equilibrium Between Proliferation and Apoptosis of Vascular Smooth Muscle Cells

    Institute of Scientific and Technical Information of China (English)

    Liu Yingmei; Fu Yuewu; Wei Yulin; Wu Wei

    2006-01-01

    Objectives By observing γ radioactive 103Pd stent affecting the proliferation and apoptosis of vascular smooth muscle cells (VSMCs) to explore the mechanism of radioactive stent preventing in-stent restenosis. Methods Fifty male New Zealand rabbits were randomized into stent group and 103Pd stent group. Control group was set up. The materials were harvested on 3, 7, 14, 28, 56 days after operation and the following investigations were carried out, including pathomorphology, immunohistochemistry, apoptosis (TUNEL) and in situs hybridization studies. Results ①The severity of the stenosis in 103Pd stent group was less than that of stent group.It was the most obvious on 56th day (P < 0.01).②The expression of PCNA of 103Pd stent group was lower than that of stent group on 3 to 28 days. It was the most obvious on 7th day, 16.35%±0.79% vs 24.36%±0.55% (P< 0.01 ). ③TUNEL method showed that the 103Pd stent group had much more apoptosis of VSMCs than that of stent group. The highest rate of apoptosis appeared on day 7, 14.72%±0.53% vs 12.42%±1.13% (P<0.01). ④ By calculating the ratio of PCNA/apoptosis (P:A), a much lower ratio was seen in 103Pd-stent group than that of stent group at 3 to 28 days. There was significant statistic difference between two groups (P<0.05). ⑤For bcl-2/bax ratio, the result in 103Pd-stent group was lower than that of stent group at 3 to 28 days. It had significant statistic difference (P < 0.05). Conclusions γ radioactive stent can inhibit the proliferation and accelerate apoptosis of injured media VSMCs. Also it can decrease the ratio of proliferation to apoptosis and relieve the severity of restenosis.

  9. Assessment of blood-retinal barrier integrity.

    Science.gov (United States)

    Vinores, S A

    1995-01-01

    The blood-retinal barrier consists of two components which are comprised of the retinal vascular endothelium and the retinal pigment epithelium, respectively. Its functional integrity can be recognized by tight junctions between these cells with a paucity of endocytic vesicles within them and the presence of the molecules that regulate the ionic and metabolic gradients that constitute the barrier. The barrier is compromised in several disease processes and by a variety of agents, but in most cases the location and mechanism for barrier failure is not understood. Perfusion with a variety of radiolabeled tracer molecules, vitreous fluorophotometry, or magnetic resonance imaging can be used to quantitate blood-retinal barrier leakage. Fluorescein angiography or magnetic resonance imaging can localize sites of leakage in vivo with limited resolution. Evans blue dye can be used to visualize blood-retinal barrier failure in gross pathological specimens and immuno-histochemical labeling of serum proteins such as albumin or fibrinogen can be used to localize sites of blood-retinal barrier breakdown by light microscopy. Tracers such as horseradish peroxidase, microperoxidase, or lanthanum, or the immunocytochemical demonstration of albumin can be used to reveal blood-retinal barrier breakdown at the ultrastructural level and provide insights into the mechanisms involved. This review discusses the advantages and limitations of each of these methods to aid in selection of the appropriate techniques to derive the desired information.

  10. Src tyrosine kinase regulates the stem cell factor–induced breakdown of the blood–retinal barrier

    Science.gov (United States)

    Im, Ji-Eun; Song, Sun-Hwa

    2016-01-01

    Purpose Stem cell factor (SCF) has been recently acknowledged as a novel endothelial permeability factor. However, the mechanisms by which SCF-induced activation of the SCF cognate receptor, cKit, enhances endothelial permeability have not been fully elucidated. This study aimed to investigate the role of Src in SCF-induced breakdown of the blood–retinal barrier (BRB). Methods In vitro endothelial permeability and in vivo retinal vascular permeability assays were performed to investigate the role of Src in SCF-induced breakdown of the BRB. Immunofluorescence staining experiments were performed to analyze the cellular distribution of phosphorylated Src and vascular endothelial (VE)-cadherin. Results SCF markedly reduced electric resistance across the human retinal vascular endothelial monolayer in vitro and enhanced extravasation of dyes in murine retinal vasculature in vivo. Inhibition of cKit activation using cKit mutant mice and chemical inhibitor substantially diminished the ability of SCF to increase endothelial permeability and retinal vascular leakage. In human retinal vascular endothelial cells, SCF induced strong phosphorylation of Src and distinct localization of phosphorylated Src in the plasma membrane. Inhibition of Src activation using chemical inhibitors abolished the SCF-induced hyperpermeability of human retinal vascular endothelial cells and retinal vascular leakage in mice. In addition, treatment with Src inhibitors restored junctional expression of VE-cadherin that disappeared in SCF-treated retinal endothelial cells and retinal vasculature. Conclusions These results showed the important role of Src in mediating SCF-induced breakdown of the BRB and retinal vascular leakage. Given that increased retinal vascular permeability is a common manifestation of various ocular diseases, the SCF/cKit/Src signaling pathway may be involved in the development of the hyperpermeable retinal vasculature in many ocular disorders.

  11. Vascular Cures

    Science.gov (United States)

    ... Contact Us Vascular Disease What is Vascular Disease? Education and Awareness Vascular Diseases Abdominal Aortic Aneurysm Aortic Dissection Arteriovenous Malformation Atherosclerosis Buerger's Disease Carotid Artery Disease ...

  12. Vascular Risk Factors in Patients with Different Subtypes of Ischemic Stroke May Affect Their Outcome after Intravenous tPA.

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    Yi Dong

    Full Text Available Intravenous (i.v. tissue-type plasminogen activator (tPA is the only approved noninvasive therapy for acute ischemic stroke (AIS. However, after tPA treatment, the outcome of patients with different subtypes of stroke according to their vascular risk factors remains to be elucidated. We aim to explore the relationship between the outcome and different risk factors in patients with different subtype of acute strokes treated with i.v. tPA. Records of patients in this cohort were reviewed. Data collected and analysed included the demographics, vascular risk factors, baseline National Institutes of Health Stroke Scale (NIHSS scores, 90-day modified Rankin Scores (mRS, and subtypes of stroke. By using the 90-day mRS, patients were dichotomized into favorable versus unfavorable outcome in each subtype of stroke. We identified the vascular risk factors that are likely associated with the poor outcome in each subtype. Among 570 AIS patients received i.v. tPA, 217 were in the large artery atherosclerosis (LAA group, 146 in the small vessel occlusion (SVO group, and 140 in the cardioaortic embolism (CE group. Lower NIHSS score on admission was related to favorable outcome in patients in all subtypes. Patients with history of dyslipidemia were likely on statin treatment before their admission and hence less likely to have elevated cholesterol level on admission. Therefore, there was a possible paradoxical effect on the outcome in patients with LAA and SVO subtypes of strokes. SVO patients with history of diabetes had higher risk of unfavorable outcome. SVO patients had favorable outcome if their time from onset to treatment was short. In conclusion, the outcome of patients treated with i.v. tPA may be related to different vascular risk factors associated with different subtypes of stroke.

  13. Vascular Risk Factors in Patients with Different Subtypes of Ischemic Stroke May Affect Their Outcome after Intravenous tPA

    Science.gov (United States)

    Ren, Jinma; Nair, Deepak S.; Parker, Sarah; Jahnel, Jan L.; Swanson-Devlin, Teresa G.; Beck, Judith M.; Mathews, Maureen; McNeil, Clayton J.; Upadhyaya, Manas; Gao, Yuan; Dong, Qiang; Wang, David Z.

    2015-01-01

    Intravenous (IV) tissue-type plasminogen activator (tPA) is the only approved noninvasive therapy for acute ischemic stroke (AIS). However, after tPA treatment, the outcome of patients with different subtypes of stroke according to their vascular risk factors remains to be elucidated. We aim to explore the relationship between the outcome and different risk factors in patients with different subtype of acute strokes treated with IV tPA. Records of patients in this cohort were reviewed. Data collected and analysed included the demographics, vascular risk factors, baseline National Institutes of Health Stroke Scale (NIHSS) scores, 90-day modified Rankin Scores (mRS), and subtypes of stroke. By using the 90-day mRS, patients were dichotomized into favorable versus unfavorable outcome in each subtype of stroke. We identified the vascular risk factors that are likely associated with the poor outcome in each subtype. Among 570 AIS patients received IV tPA, 217 were in the large artery atherosclerosis (LAA) group, 146 in the small vessel occlusion(SVO) group, and 140 in the cardioaortic embolism(CE) group. Lower NIHSS score on admission was related to favorable outcome in patients in all subtypes. Patients with history of dyslipidemia were likely on statin treatment before their admission and hence less likely to have elevated cholesterol level on admission. Therefore, there was a possible paradoxical effect on the outcome in patients with LAA and SVO subtypes of strokes. SVO patients with history of diabetes had higher risk of unfavorable outcome. SVO patients had favorable outcome if their time from onset to treatment was short. In conclusion, the outcome of patients treated with IV tPA may be related to different vascular risk factors associated with different subtypes of stroke. PMID:26247772

  14. Retinal Vessel Oxygen Saturation during 100% Oxygen Breathing in Healthy Individuals.

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    Olof Birna Olafsdottir

    Full Text Available To detect how systemic hyperoxia affects oxygen saturation in retinal arterioles and venules in healthy individuals.Retinal vessel oxygen saturation was measured in 30 healthy individuals with a spectrophotometric retinal oximeter (Oxymap T1. Oximetry was performed during breathing of room air, 100% oxygen (10 minutes, 6L/min and then again room air (10 minutes recovery.Mean oxygen saturation rises modestly in retinal arterioles during 100% oxygen breathing (94.5%±3.8 vs. 92.0%±3.7% at baseline, p<0.0001 and dramatically in retinal venules (76.2%±8.0% vs. 51.3%±5.6%, p<0.0001. The arteriovenous difference decreased during 100% oxygen breathing (18.3%±9.0% vs. 40.7%±5.7%, p<0.0001. The mean diameter of arterioles decreased during 100% oxygen breathing compared to baseline (9.7±1.4 pixels vs. 10.3±1.3 pixels, p<0.0001 and the same applies to the mean venular diameter (11.4±1.2 pixels vs. 13.3±1.5 pixels, p<0.0001.Breathing 100% oxygen increases oxygen saturation in retinal arterioles and more so in venules and constricts them compared to baseline levels. The dramatic increase in oxygen saturation in venules reflects oxygen flow from the choroid and the unusual vascular anatomy and oxygen physiology of the eye.

  15. Genetic loci for retinal arteriolar microcirculation.

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    Xueling Sim

    Full Text Available Narrow arterioles in the retina have been shown to predict hypertension as well as other vascular diseases, likely through an increase in the peripheral resistance of the microcirculatory flow. In this study, we performed a genome-wide association study in 18,722 unrelated individuals of European ancestry from the Cohorts for Heart and Aging Research in Genomic Epidemiology consortium and the Blue Mountain Eye Study, to identify genetic determinants associated with variations in retinal arteriolar caliber. Retinal vascular calibers were measured on digitized retinal photographs using a standardized protocol. One variant (rs2194025 on chromosome 5q14 near the myocyte enhancer factor 2C MEF2C gene was associated with retinal arteriolar caliber in the meta-analysis of the discovery cohorts at genome-wide significance of P-value <5×10(-8. This variant was replicated in an additional 3,939 individuals of European ancestry from the Australian Twins Study and Multi-Ethnic Study of Atherosclerosis (rs2194025, P-value = 2.11×10(-12 in combined meta-analysis of discovery and replication cohorts. In independent studies of modest sample sizes, no significant association was found between this variant and clinical outcomes including coronary artery disease, stroke, myocardial infarction or hypertension. In conclusion, we found one novel loci which underlie genetic variation in microvasculature which may be relevant to vascular disease. The relevance of these findings to clinical outcomes remains to be determined.

  16. Genetic loci for retinal arteriolar microcirculation.

    Science.gov (United States)

    Sim, Xueling; Jensen, Richard A; Ikram, M Kamran; Cotch, Mary Frances; Li, Xiaohui; MacGregor, Stuart; Xie, Jing; Smith, Albert Vernon; Boerwinkle, Eric; Mitchell, Paul; Klein, Ronald; Klein, Barbara E K; Glazer, Nicole L; Lumley, Thomas; McKnight, Barbara; Psaty, Bruce M; de Jong, Paulus T V M; Hofman, Albert; Rivadeneira, Fernando; Uitterlinden, Andre G; van Duijn, Cornelia M; Aspelund, Thor; Eiriksdottir, Gudny; Harris, Tamara B; Jonasson, Fridbert; Launer, Lenore J; Attia, John; Baird, Paul N; Harrap, Stephen; Holliday, Elizabeth G; Inouye, Michael; Rochtchina, Elena; Scott, Rodney J; Viswanathan, Ananth; Li, Guo; Smith, Nicholas L; Wiggins, Kerri L; Kuo, Jane Z; Taylor, Kent D; Hewitt, Alex W; Martin, Nicholas G; Montgomery, Grant W; Sun, Cong; Young, Terri L; Mackey, David A; van Zuydam, Natalie R; Doney, Alex S F; Palmer, Colin N A; Morris, Andrew D; Rotter, Jerome I; Tai, E Shyong; Gudnason, Vilmundur; Vingerling, Johannes R; Siscovick, David S; Wang, Jie Jin; Wong, Tien Y

    2013-01-01

    Narrow arterioles in the retina have been shown to predict hypertension as well as other vascular diseases, likely through an increase in the peripheral resistance of the microcirculatory flow. In this study, we performed a genome-wide association study in 18,722 unrelated individuals of European ancestry from the Cohorts for Heart and Aging Research in Genomic Epidemiology consortium and the Blue Mountain Eye Study, to identify genetic determinants associated with variations in retinal arteriolar caliber. Retinal vascular calibers were measured on digitized retinal photographs using a standardized protocol. One variant (rs2194025 on chromosome 5q14 near the myocyte enhancer factor 2C MEF2C gene) was associated with retinal arteriolar caliber in the meta-analysis of the discovery cohorts at genome-wide significance of P-value <5×10(-8). This variant was replicated in an additional 3,939 individuals of European ancestry from the Australian Twins Study and Multi-Ethnic Study of Atherosclerosis (rs2194025, P-value = 2.11×10(-12) in combined meta-analysis of discovery and replication cohorts). In independent studies of modest sample sizes, no significant association was found between this variant and clinical outcomes including coronary artery disease, stroke, myocardial infarction or hypertension. In conclusion, we found one novel loci which underlie genetic variation in microvasculature which may be relevant to vascular disease. The relevance of these findings to clinical outcomes remains to be determined.

  17. The implication of omega-3 polyunsaturated fatty acids in retinal physiology

    Directory of Open Access Journals (Sweden)

    Acar Niyazi

    2007-05-01

    Full Text Available Neuronal tissues such as the retina and the brain are characterized by their high content in phospholipids. In the retina, phospholipids can account for until 80% of total lipids and are mainly composed by species belonging to phosphatidyl-choline and phosphatidyl-ethanolamine sub-classes. Within fatty acids esterified on retinal phospholipids, omega-3 PUFAs are major components since docosahexaenoic acid (DHA can represent until 50% of total fatty acids in the photoreceptor outer segments. For long time, DHA is known to play a major role in membrane function and subsequently in visual processes by affecting permeability, fluidity, thickness and the activation of membrane-bound proteins. Today, more and more studies show that PUFAs from the omega-3 series may also operate as protective factors in retinal vascular and immuno-regulatory processes, in maintaining the physiologic redox balance and in cell survival. They may operate within complex systems involving eicosanoids, angiogenic factors, inflammatory factors and matrix metalloproteinases. This new and emerging concept based on the interrelationship of omega-3 PUFAs with neural and vascular structure and function appears to be essential when considering retinal diseases of public health significance such as age-related macular degeneration.

  18. Ultrasound -- Vascular

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z Ultrasound - Vascular Vascular ultrasound uses sound waves to evaluate ... the limitations of Vascular Ultrasound? What is Vascular Ultrasound? Ultrasound is safe and painless, and produces pictures ...

  19. Retinal Inhibition of CCR3 Induces Retinal Cell Death in a Murine Model of Choroidal Neovascularization.

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    Haibo Wang

    Full Text Available Inhibition of chemokine C-C motif receptor 3 (CCR3 signaling has been considered as treatment for neovascular age-related macular degeneration (AMD. However, CCR3 is expressed in neural retina from aged human donor eyes. Therefore, broad CCR3 inhibition may be harmful to the retina. We assessed the effects of CCR3 inhibition on retina and choroidal endothelial cells (CECs that develop into choroidal neovascularization (CNV. In adult murine eyes, CCR3 colocalized with glutamine-synthetase labeled Műller cells. In a murine laser-induced CNV model, CCR3 immunolocalized not only to lectin-stained cells in CNV lesions but also to the retina. Compared to non-lasered controls, CCR3 mRNA was significantly increased in laser-treated retina. An intravitreal injection of a CCR3 inhibitor (CCR3i significantly reduced CNV compared to DMSO or PBS controls. Both CCR3i and a neutralizing antibody to CCR3 increased TUNEL+ retinal cells overlying CNV, compared to controls. There was no difference in cleaved caspase-3 in laser-induced CNV lesions or in overlying retina between CCR3i- or control-treated eyes. Following CCR3i, apoptotic inducible factor (AIF was significantly increased and anti-apoptotic factor BCL2 decreased in the retina; there were no differences in retinal vascular endothelial growth factor (VEGF. In cultured human Műller cells exposed to eotaxin (CCL11 and VEGF, CCR3i significantly increased TUNEL+ cells and AIF but decreased BCL2 and brain derived neurotrophic factor, without affecting caspase-3 activity or VEGF. CCR3i significantly decreased AIF in RPE/choroids and immunostaining of phosphorylated VEGF receptor 2 (p-VEGFR2 in CNV with a trend toward reduced VEGF. In cultured CECs treated with CCL11 and/or VEGF, CCR3i decreased p-VEGFR2 and increased BCL2 without increasing TUNEL+ cells and AIF. These findings suggest that inhibition of retinal CCR3 causes retinal cell death and that targeted inhibition of CCR3 in CECs may be a safer if CCR3

  20. Retinal stem/progenitor cells in the ciliary marginal zone complete retinal regeneration: a study of retinal regeneration in a novel animal model.

    Science.gov (United States)

    Miyake, Ayumi; Araki, Masasuke

    2014-07-01

    Our research group has extensively studied retinal regeneration in adult Xenopus laevis. However, X. laevis does not represent a suitable model for multigenerational genetics and genomic approaches. Instead, Xenopus tropicalis is considered as the ideal model for these studies, although little is known about retinal regeneration in X. tropicalis. In the present study, we showed that a complete retina regenerates at approximately 30 days after whole retinal removal. The regenerating retina was derived from the stem/progenitor cells in the ciliary marginal zone (CMZ), indicating a novel mode of vertebrate retinal regeneration, which has not been previously reported. In a previous study, we showed that in X. laevis, retinal regeneration occurs primarily through the transdifferentiation of retinal pigmented epithelial (RPE) cells. RPE cells migrate to the retinal vascular membrane and reform a new epithelium, which then differentiates into the retina. In X. tropicalis, RPE cells also migrated to the vascular membrane, but transdifferentiation was not evident. Using two tissue culture models of RPE tissues, it was shown that in X. laevis RPE culture neuronal differentiation and reconstruction of the retinal three-dimensional (3-D) structure were clearly observed, while in X. tropicalis RPE culture neither ßIII tubulin-positive cells nor 3-D retinal structure were seen. These results indicate that the two Xenopus species are excellent models to clarify the cellular and molecular mechanisms of retinal regeneration, as these animals have contrasting modes of regeneration; one mode primarily involves RPE cells and the other mode involves stem/progenitor cells in the CMZ.

  1. Spink2 modulates apoptotic susceptibility and is a candidate gene in the Rgcs1 QTL that affects retinal ganglion cell death after optic nerve damage.

    Directory of Open Access Journals (Sweden)

    Joel A Dietz

    Full Text Available The Rgcs1 quantitative trait locus, on mouse chromosome 5, influences susceptibility of retinal ganglion cells to acute damage of the optic nerve. Normally resistant mice (DBA/2J congenic for the susceptible allele from BALB/cByJ mice exhibit susceptibility to ganglion cells, not only in acute optic nerve crush, but also to chronic inherited glaucoma that is characteristic of the DBA/2J strain as they age. SNP mapping of this QTL has narrowed the region of interest to 1 Mb. In this region, a single gene (Spink2 is the most likely candidate for this effect. Spink2 is expressed in retinal ganglion cells and is increased after optic nerve damage. This gene is also polymorphic between resistant and susceptible strains, containing a single conserved amino acid change (threonine to serine and a 220 bp deletion in intron 1 that may quantitatively alter endogenous expression levels between strains. Overexpression of the different variants of Spink2 in D407 tissue culture cells also increases their susceptibility to the apoptosis-inducing agent staurosporine in a manner consistent with the differential susceptibility between the DBA/2J and BALB/cByJ strains.

  2. Microvascular Abnormality in Schizophrenia as Shown by Retinal Imaging

    Science.gov (United States)

    Meier, Madeline H.; Shalev, Idan; Moffitt, Terrie E.; Kapur, Shitij; Keefe, Richard S.E.; Wong, Tien; Belsky, Daniel W.; Harrington, HonaLee; Hogan, Sean; Houts, Renate; Caspi, Avshalom; Poulton, Richie

    2013-01-01

    Objective Retinal and cerebral microvessels are structurally and functionally homologous, but, unlike cerebral microvessels, retinal microvessels can be noninvasively measured in vivo via retinal imaging. Here we test the hypothesis that individuals with schizophrenia show microvascular abnormality and evaluate the utility of retinal imaging as a tool for future schizophrenia research. Methods Participants were members of the Dunedin Study, a population-representative cohort followed from birth with 95% retention. Study members underwent retinal imaging at age 38 years. We assessed retinal arteriolar and venular caliber for all members of the cohort, including individuals who developed schizophrenia. Results Study members who developed schizophrenia were distinguished by wider retinal venules, suggesting microvascular abnormality reflective of insufficient brain oxygen supply. Analyses that controlled for confounding health conditions suggested that wider retinal venules are not simply an artifact of co-occurring health problems in schizophrenia patients. Wider venules were also associated with a dimensional measure of adult psychosis symptoms and with psychosis symptoms reported in childhood. Conclusions Findings provide initial support for the hypothesis that individuals with schizophrenia show microvascular abnormality. Moreover, results suggest that the same vascular mechanisms underlie subthreshold symptoms and clinical disorder and that these associations may begin early in life. These findings highlight the promise of retinal imaging as a tool for understanding the pathogenesis of schizophrenia. PMID:24030514

  3. Photostress Testing Device for Diagnosing Retinal Disease

    Directory of Open Access Journals (Sweden)

    Elizabeth Swan

    2014-08-01

    Full Text Available Retinal diseases such as Age-Related Macular Degeneration (ARMD affect nearly one in three elderly patients. ARMD damages the central vision photoreceptors in the fovea. The Photostress Test is a simple technique for testing for the early effects of ARMD. Here, the illumination sources in a novel self-administered Photostress Testing device were modeled for safety and distribution in illumination software. After satisfying the design constraints in the model, a prototype of the illumination system was fabricated and tested to confirm the modeling results. The resultant prototype can be used to aid in the diagnosis of retinal disease and is well within retinal safety levels.

  4. Multiple extra macular branch retinal vein occlusions in hyperhomocysteinemia

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    Abhijit Diwakar Gore

    2014-01-01

    Full Text Available Hyperhomocysteinemia is a well-known modifiable risk factor for thromboembolism. Retinal vascular occlusion in patients having hyperhomocysteinemia is a known entity, particularly in young patients. However, multiple extra macular branch retinal vein occlusion (BRVO is a rare condition, which can be a presentation of this disease. We present a patient who had multiple extra macular BRVO; on complete systemic workup, he was found to have raised homocysteine levels.

  5. Differential modulation of retinal degeneration by Ccl2 and Cx3cr1 chemokine signalling.

    Science.gov (United States)

    Luhmann, Ulrich F O; Lange, Clemens A; Robbie, Scott; Munro, Peter M G; Cowing, Jill A; Armer, Hannah E J; Luong, Vy; Carvalho, Livia S; MacLaren, Robert E; Fitzke, Frederick W; Bainbridge, James W B; Ali, Robin R

    2012-01-01

    Microglia and macrophages are recruited to sites of retinal degeneration where local cytokines and chemokines determine protective or neurotoxic microglia responses. Defining the role of Ccl2-Ccr2 and Cx3cl1-Cx3cr1 signalling for retinal pathology is of particular interest because of its potential role in age-related macular degeneration (AMD). Ccl2, Ccr2, and Cx3cr1 signalling defects impair macrophage trafficking, but have, in several conflicting studies, been reported to show different degrees of age-related retinal degeneration. Ccl2/Cx3cr1 double knockout (CCDKO) mice show an early onset retinal degeneration and have been suggested as a model for AMD. In order to understand phenotypic discrepancies in different chemokine knockout lines and to study how defects in Ccl2 and/or Cx3cr1 signalling contribute to the described early onset retinal degeneration, we defined primary and secondary pathological events in CCDKO mice. To control for genetic background variability, we compared the original phenotype with that of single Ccl2, Cx3cr1 and Ccl2/Cx3cr1 double knockout mice obtained from backcrosses of CCDKO with C57Bl/6 mice. We found that the primary pathological event in CCDKO mice develops in the inferior outer nuclear layer independently of light around postnatal day P14. RPE and vascular lesions develop secondarily with increasing penetrance with age and are clinically similar to retinal telangiectasia not to choroidal neovascularisation. Furthermore, we provide evidence that a third autosomal recessive gene causes the degeneration in CCDKO mice and in all affected re-derived lines and subsequently demonstrated co-segregation of the naturally occurring RD8 mutation in the Crb1 gene. By comparing CCDKO mice with re-derived CCl2(-/-)/Crb1(Rd8/RD8), Cx3cr1(-/-)/Crb1(Rd8/RD8) and CCl2(-/-)/Cx3cr1(-/-)/Crb1(Rd8/RD8) mice, we observed a differential modulation of the retinal phenotype by genetic background and both chemokine signalling pathways. These findings

  6. Combined central retinal artery and vein occlusion in Churg-Strauss syndrome

    DEFF Research Database (Denmark)

    Hamann, Steffen; Johansen, Sven; Hamann, Steffen Ellitsgaard

    2006-01-01

    PURPOSE: To describe a rare case of Churg-Strauss syndrome presenting with severe visual loss due to a combined central retinal vein and artery occlusion. METHODS: A 42-year old man with a medical history of asthma and blood hypereosinophilia developed a sudden loss of vision in his right eye. We...... describe the clinical features and evolution of the case after treatment. RESULTS: A combined occlusion of the central retinal artery and central retinal vein was diagnosed by the funduscopic appearance of retinal whitening, macular cherry-red spot, papilloedema, retinal haemorrhages in all four quadrants...... the vascular occlusion and experienced no visual improvement. CONCLUSION: Combined central retinal artery and vein occlusion can occur in Churg-Strauss syndrome. We suggest that regional vasculitis may be the pathological mechanism underlying the vascular occlusions observed in our case. The condition carries...

  7. Retinal Image Analysis for Abnormality Detection-An Overview

    Directory of Open Access Journals (Sweden)

    R. Karthikeyan

    2012-01-01

    Full Text Available Problem statement: Classification plays a major role in retinal image analysis for detecting the various abnormalities in retinal images. Classification refers to one of the mining concepts using supervised or unsupervised learning techniques. Approach: Diabetic retinopathy is one of the common complications of diabetes. Unfortunately, in many cases, the patient is not aware of any symptoms until it is too late for effective treatment. Diabetic retinopathy is the leading cause of blindness. Diabetic retinopathy results in retinal disorders that include microaneursyms, drusens, hard exudates and intra-retinal micro-vascular abnormalities. Results: Automatic methods to detect various lesions associated with diabetic retinopathy facilitate the opthalmologists in accurate diagnosis and treatment planning. Abnormal retinal images fall into four different classes namely Non-Proliferative Diabetic Retinopathy (NPDR, Central Retinal Vein Occlusion (CRVO, Choroidal Neo-Vascularization Membrane (CNVM and Central Serous Retinopathy (CSR.. Conclusion: In this study, we have analysed the various methodologies for detecting the abnormalities in retinal images automatically along with their merits and demerits and proposed the new framework for detection of abnormalities using Cellular Neural Network (CNN.

  8. Profound retinal ischaemia after ranibizumab administration in an eye with ocular ischaemic syndrome

    DEFF Research Database (Denmark)

    Kofoed, Peter Kristian; Munch, Inger Christine; Larsen, Michael

    2009-01-01

    Abstract. Purpose: To report the result of ranibizumab administration in an eye with ocular ischaemic syndrome. Methods: Fluorescein angiography, ocular pneumoplethysmography and retinal vessel calibre measurement. Results: An 85-year-old man with ocular ischaemic syndrome demonstrated vision loss......, retinal vessel calibre constriction and profound retinal ischaemia after intravitreal ranibizumab. Conclusion: We advise against the use of intravitreal vascular endothelial growth factor inhibitors in eyes with ocular ischaemic syndrome....

  9. Pericytes derived from adipose-derived stem cells protect against retinal vasculopathy.

    Directory of Open Access Journals (Sweden)

    Thomas A Mendel

    Full Text Available BACKGROUND: Retinal vasculopathies, including diabetic retinopathy (DR, threaten the vision of over 100 million people. Retinal pericytes are critical for microvascular control, supporting retinal endothelial cells via direct contact and paracrine mechanisms. With pericyte death or loss, endothelial dysfunction ensues, resulting in hypoxic insult, pathologic angiogenesis, and ultimately blindness. Adipose-derived stem cells (ASCs differentiate into pericytes, suggesting they may be useful as a protective and regenerative cellular therapy for retinal vascular disease. In this study, we examine the ability of ASCs to differentiate into pericytes that can stabilize retinal vessels in multiple pre-clinical models of retinal vasculopathy. METHODOLOGY/PRINCIPAL FINDINGS: We found that ASCs express pericyte-specific markers in vitro. When injected intravitreally into the murine eye subjected to oxygen-induced retinopathy (OIR, ASCs were capable of migrating to and integrating with the retinal vasculature. Integrated ASCs maintained marker expression and pericyte-like morphology in vivo for at least 2 months. ASCs injected after OIR vessel destabilization and ablation enhanced vessel regrowth (16% reduction in avascular area. ASCs injected intravitreally before OIR vessel destabilization prevented retinal capillary dropout (53% reduction. Treatment of ASCs with transforming growth factor beta (TGF-β1 enhanced hASC pericyte function, in a manner similar to native retinal pericytes, with increased marker expression of smooth muscle actin, cellular contractility, endothelial stabilization, and microvascular protection in OIR. Finally, injected ASCs prevented capillary loss in the diabetic retinopathic Akimba mouse (79% reduction 2 months after injection. CONCLUSIONS/SIGNIFICANCE: ASC-derived pericytes can integrate with retinal vasculature, adopting both pericyte morphology and marker expression, and provide functional vascular protection in multiple

  10. Automatic classification of retinal vessels into arteries and veins

    Science.gov (United States)

    Niemeijer, Meindert; van Ginneken, Bram; Abràmoff, Michael D.

    2009-02-01

    Separating the retinal vascular tree into arteries and veins is important for quantifying vessel changes that preferentially affect either the veins or the arteries. For example the ratio of arterial to venous diameter, the retinal a/v ratio, is well established to be predictive of stroke and other cardiovascular events in adults, as well as the staging of retinopathy of prematurity in premature infants. This work presents a supervised, automatic method that can determine whether a vessel is an artery or a vein based on intensity and derivative information. After thinning of the vessel segmentation, vessel crossing and bifurcation points are removed leaving a set of vessel segments containing centerline pixels. A set of features is extracted from each centerline pixel and using these each is assigned a soft label indicating the likelihood that it is part of a vein. As all centerline pixels in a connected segment should be the same type we average the soft labels and assign this average label to each centerline pixel in the segment. We train and test the algorithm using the data (40 color fundus photographs) from the DRIVE database1 with an enhanced reference standard. In the enhanced reference standard a fellowship trained retinal specialist (MDA) labeled all vessels for which it was possible to visually determine whether it was a vein or an artery. After applying the proposed method to the 20 images of the DRIVE test set we obtained an area under the receiver operator characteristic (ROC) curve of 0.88 for correctly assigning centerline pixels to either the vein or artery classes.

  11. Vascular endothelial growth inhibitor affects the invasion, apoptosis and vascularisation in breast cancer cell line MDA-MB-231

    Institute of Scientific and Technical Information of China (English)

    Gao Yinguang; Ge Zhicheng; Zhang Zhongtao; Bai Zhigang; Ma Xuemei; Wang Yu

    2014-01-01

    Background Breast cancer is one of the most common malignant female diseases worldwide.It is a significant threat to every woman's health.Vascular endothelial growth inhibitor (VEGI) is known to be abundant in endothelial cells.According to previous literature,overexpression of VEGI has been shown to inhibit tumor neovascularisation and progression in cellular and animal models,but there has been limited research on the significance of VEGI in the breast cancer.Methods In our study,cell lines MDA-MB-231 were first constructed in which VEGI mediated by lentivirus over-expressed.The effects of VEGI over-expression on MDA-MB-231 cells were investigated both in vitro and in vivo.The expression of VEGI in the MDA-MB-231 cells after infection of lentivirus was analyzed using real-time PCR and Western blotting.The effect of the biological characteristics of MDA-MB-231 cells was assessed by growth,invasion,adhesion,and migration assay with subcutaneous tumor-bearing nude mice models.Then the growth curves of the subcutaneous tumors were studied.Expressions of VEGI,CD31 and CD34 in the tumors were analyzed by immunohistochemistry and apoptosis was detected by flow cytometry and immunohistochemistry.Results Infection of MDA-MB-231 cells within the lentivirus resulted in approximately a 1 000-fold increase in the expression of VEGI.As can be seen in the invasion,adhesion and migration assay,the over-expression of VEGI can inhibit the ability of MDA-MB-231 cells during migration,adhesion and invasion.The volume of the subcutaneous tumor in the over-expression group was distinctly and significantly less than that of the control groups.Immunohistochemistry analysis of the tumor biopsies cleady showed the expression of VEGI in the over-expression group increased while CD31 and CD34 decreased significantly.In vitro and in vivo,the early apoptosis rate and the apoptosis index were increased within the VEGI over-expression group as compared with the control group.Conclusions Taken

  12. Consumption of Polyphenol-Rich Zingiber Zerumbet Rhizome Extracts Protects against the Breakdown of the Blood-Retinal Barrier and Retinal Inflammation Induced by Diabetes

    Directory of Open Access Journals (Sweden)

    Thing-Fong Tzeng

    2015-09-01

    Full Text Available The present study investigates the amelioration of diabetic retinopathy (DR by Zingiber zerumbet rhizome ethanol extracts (ZZRext in streptozotocin-induced diabetic rats (STZ-diabetic rats. ZZRext contains high phenolic and flavonoid contents. STZ-diabetic rats were treated orally with ZZRext (200, 300 mg/kg per day for three months. Blood-retinal barrier (BRB breakdown and increased vascular permeability were found in diabetic rats, with downregulation of occludin, and claudin-5. ZZRext treatment effectively preserved the expression of occludin, and claudin-5, leading to less BRB breakdown and less vascular permeability. Retinal histopathological observation showed that the disarrangement and reduction in thickness of retinal layers were reversed in ZZRext-treated diabetic rats. Retinal gene expression of tumor necrosis factor-α, interleukin (IL-1β, IL-6, vascular endothelial growth factor, intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 were all decreased in ZZRext-treated diabetic rats. Moreover, ZZRext treatment not only inhibited the nuclear factor κB (NF-κB activation, but also downregulated the protein expression of p38 mitogen-activated protein kinase (MAPK in diabetic retina. In conclusion, the results suggest that the retinal protective effects of ZZRext occur through improved retinal structural change and inhibiting retinal inflammation. The antiretinopathy property of ZZRext might be related to the downregulation of p38 MAPK and NF-κB signal transduction induced by diabetes.

  13. Flow patterns on spectral-domain optical coherence tomography reveal flow directions at retinal vessel bifurcations

    DEFF Research Database (Denmark)

    Willerslev, Anne; Li, Xiao Q; Munch, Inger C

    2014-01-01

    PURPOSE: To study intravascular characteristics of flowing blood in retinal vessels using spectral-domain optical coherence tomography (SD-OCT). METHODS: Examination of selected arterial bifurcations and venous sites of confluence in 25 healthy 11-year-old children recruited as an ad hoc subsample...... be determined using SD-OCT. This feature may assist the identification of flow reversal near sites of vascular occlusion, the analysis of blood flow near vascular malformations and the segmentation of retinal SD-OCT images....

  14. Retinal remodeling in human retinitis pigmentosa.

    Science.gov (United States)

    Jones, B W; Pfeiffer, R L; Ferrell, W D; Watt, C B; Marmor, M; Marc, R E

    2016-09-01

    Retinitis Pigmentosa (RP) in the human is a progressive, currently irreversible neural degenerative disease usually caused by gene defects that disrupt the function or architecture of the photoreceptors. While RP can initially be a disease of photoreceptors, there is increasing evidence that the inner retina becomes progressively disorganized as the outer retina degenerates. These alterations have been extensively described in animal models, but remodeling in humans has not been as well characterized. This study, using computational molecular phenotyping (CMP) seeks to advance our understanding of the retinal remodeling process in humans. We describe cone mediated preservation of overall topology, retinal reprogramming in the earliest stages of the disease in retinal bipolar cells, and alterations in both small molecule and protein signatures of neurons and glia. Furthermore, while Müller glia appear to be some of the last cells left in the degenerate retina, they are also one of the first cell classes in the neural retina to respond to stress which may reveal mechanisms related to remodeling and cell death in other retinal cell classes. Also fundamentally important is the finding that retinal network topologies are altered. Our results suggest interventions that presume substantial preservation of the neural retina will likely fail in late stages of the disease. Even early intervention offers no guarantee that the interventions will be immune to progressive remodeling. Fundamental work in the biology and mechanisms of disease progression are needed to support vision rescue strategies.

  15. Regeneration of the retina: toward stem cell therapy for degenerative retinal diseases.

    Science.gov (United States)

    Jeon, Sohee; Oh, Il-Hoan

    2015-04-01

    Degenerative retinal diseases affect millions of people worldwide, which can lead to the loss of vision. However, therapeutic approaches that can reverse this process are limited. Recent efforts have allowed the possibility of the stem cell-based regeneration of retinal cells and repair of injured retinal tissues. Although the direct differentiation of pluripotent stem cells into terminally differentiated photoreceptor cells comprises one approach, a series of studies revealed the intrinsic regenerative potential of the retina using endogenous retinal stem cells. Muller glial cells, ciliary pigment epithelial cells, and retinal pigment epithelial cells are candidates for such retinal stem cells that can differentiate into multiple types of retinal cells and be integrated into injured or developing retina. In this review, we explore our current understanding of the cellular identity of these candidate retinal stem cells and their therapeutic potential for cell therapy against degenerative retinal diseases.

  16. 原发性高血压患者视网膜微血管径与代谢综合征及组份的相关性研究%The relationship between retinal vascular calibers and components of the metabolic syndrome

    Institute of Scientific and Technical Information of China (English)

    易茜璐; 李晓牧; 袁源智; 于明香; 陆志强; 高鑫

    2013-01-01

    目的 应用计算机辅助技术测定视网膜微血管径,旨在分析原发性高血压患者视网膜微血管径与代谢综合征组份之间的关系.方法 原发性高血压患者450例,采集病史,进行体格检查、代谢指标测定、眼底摄片,并测量视网膜微动脉和微静脉血管径,分析微血管径与血压、血糖及血脂等代谢综合征组份的关系及其变化的危险因素.结果 450例高血压患者平均年龄(57.53±10.01)岁,平均收缩压(138±17)mm Hg(1 mm Hg=0.133 kPa),舒张压(84± 10)mm Hg,平均视网膜微动脉径(129.26±12.68) μm,微静脉径(198.25±18.37) μm.校正年龄、性别等后,血压控制不良组的视网膜微动脉径小于控制良好组[(126.45±15.74) μm对(130.30±11.30) μm,P=0.029].随血压控制不良加重,视网膜微动脉径呈减小趋势(P=0.075).高密度脂蛋白胆固醇正常组视网膜微静脉径小于异常组[(197.36±17.62) μm对(203.07 ±21.52) μm,P=0.040].视网膜微血管径三分位比较中,随着微动脉径减小,舒张压逐渐升高(P=0.009);随着微静脉径增宽,高密度脂蛋白胆固醇逐渐降低(P=0.042).年龄增加(r=-0.090,P=0.013)、血压控制不良(r=-0.098,P=0.038)是微动脉狭窄的独立危险因素,低高密度脂蛋白胆固醇(r=0.105,P=0.024)、吸烟(r=0.141,P=0.010)是微静脉增宽的独立危险因素.结论 高血压人群中,血压控制不良与视网膜微动脉狭窄密切相关,低高密度脂蛋白胆固醇与微静脉增宽密切相关;血压控制不良、增龄是微动脉狭窄的独立危险因素,低高密度脂蛋白胆固醇、吸烟则是微静脉增宽的独立危险因素.%Objective With a computer-assisted program,retinal vascular calibers were measured quantitatively.In this study the relationship between retinal vascular calibers and components of the metabolic syndrome was examined.Methods A total of 450 hypertensive patients were collected.Medical history,physical examination,blood tests

  17. Structure and barrier properties of human embryonic stem cell-derived retinal pigment epithelial cells are affected by extracellular matrix protein coating.

    Science.gov (United States)

    Sorkio, Anni; Hongisto, Heidi; Kaarniranta, Kai; Uusitalo, Hannu; Juuti-Uusitalo, Kati; Skottman, Heli

    2014-02-01

    Extracellular matrix (ECM) interactions play a vital role in cell morphology, migration, proliferation, and differentiation of cells. We investigated the role of ECM proteins on the structure and function of human embryonic stem cell-derived retinal pigment epithelial (hESC-RPE) cells during their differentiation and maturation from hESCs into RPE cells in adherent differentiation cultures on several human ECM proteins found in native human Bruch's membrane, namely, collagen I, collagen IV, laminin, fibronectin, and vitronectin, as well as on commercial substrates of xeno-free CELLstart™ and Matrigel™. Cell pigmentation, expression of RPE-specific proteins, fine structure, as well as the production of basal lamina by hESC-RPE on different protein coatings were evaluated after 140 days of differentiation. The integrity of hESC-RPE epithelium and barrier properties on different coatings were investigated by measuring transepithelial resistance. All coatings supported the differentiation of hESC-RPE cells as demonstrated by early onset of cell pigmentation and further maturation to RPE monolayers after enrichment. Mature RPE phenotype was verified by RPE-specific gene and protein expression, correct epithelial polarization, and phagocytic activity. Significant differences were found in the degree of RPE cell pigmentation and tightness of epithelial barrier between different coatings. Further, the thickness of self-assembled basal lamina and secretion of the key ECM proteins found in the basement membrane of the native RPE varied between hESC-RPE cultured on compared protein coatings. In conclusion, this study shows that the cell culture substrate has a major effect on the structure and basal lamina production during the differentiation and maturation of hESC-RPE potentially influencing the success of cell integrations and survival after cell transplantation.

  18. Preclinical models to investigate retinal ischemia: Advances and drawbacks

    Directory of Open Access Journals (Sweden)

    Gillipsie eMinhas

    2012-05-01

    Full Text Available Retinal ischemia is a frequent source of irreparable visual impairment affecting over a hundred million individuals in the world. It is associated with a wide range of retinal disorders like ischemic optic neuropathies, obstructive retinopathies, carotid occlusive disorders, diabetic retinopathy and glaucoma. Compared to other tissues retina has a higher metabolic rate; any disruption in blood supply can have an effect on the supply of oxygen leading to retinal ischemia. If occlusion is not rescued the outcome is irreversible with ischemic and apoptotic cascades resulting in cell death. In addition to in-vitro models, animal models are necessary to further our understanding of the etiology, pathology, and evolution of retinal ischemia besides the evaluation, development, and improvement of therapeutic strategies. The various existing animal models of retinal ischemia are characterised by obstruction of retinal circulation that allows the study of neurovascular changes. In this review we provide an overview of major models and emerging preclinical therapeutic strategies.

  19. Retinal artery occlusions in children.

    Science.gov (United States)

    Dharmasena, Aruna; Wallis, Simon

    2014-01-01

    The purpose of this study is to present a case of RAO in a 13 year old girl with a preceding history of hyperextension of the neck at her hairdressers for a long duration and use of her mobile phone handset resting it against the side of her neck presumably exerting some pressure on carotids during the same time. Materials and methods of this study was reported as case report and review of literature. A 13 year-old girl presented with the left supero-nasal scotoma due to an inferior temporal branch retinal artery occlusion (BRAO). She underwent extensive investigations and no underlying cause was discovered. She gave a history of cervical extension over a long period of time while having the hair coloured twice in the preceding week. She also mentioned that she was using her mobile phone more or less continuously during both these occasions keeping it against her neck. Given the above history it is possible that the pressure on the ipsilateral carotid arteries or the prolong neck extension may have been responsible for the formation of a platelet embolus resulting in the BRAO. In conclusion, although cerebro-vascular accidents due to 'beauty parlor stroke syndrome' (JAMA 269:2085-2086, 1993) have been reported previously it has not been reported in children to our knowledge. On the other hand, 'beauty parlor stroke syndrome' occurs due to a dissection of the vertebral arteries or due to mechanical compression of the vertebral arteries during the prolonged hyperextension of the neck. The central retinal artery originates from the internal carotid circulation and it is highly unlikely for an embolus to enter the retinal circulation from the vertebral arteries. Therefore, the authors favour the possibility that the compulsive use of a mobile phone exerting pressure on the carotid arteries for a long time may have led to the formation of an embolus and subsequent RAO in this case.

  20. Microglia-Müller glia crosstalk in the rd10 mouse model of retinitis pigmentosa.

    Science.gov (United States)

    Arroba, Ana I; Alvarez-Lindo, Noemí; van Rooijen, Nico; de la Rosa, Enrique J

    2014-01-01

    Retinitis pigmentosa refers to a large, genetically heterogeneous group of retinal dystrophies. This condition is characterized by the gradual onset of blindness due to progressive deterioration of the retina, a process that includes photoreceptor and retinal-pigmented-epithelium cell decay and death, microglial recruitment, reactive gliosis, and vascular disorganization and regression. We found that early in the degenerative process, the rd10 mouse retina exhibits high levels of photoreceptor cell death and reactive Müller gliosis. In explant cultures, both degenerative processes were abrogated by IGF-I treatment. Moreover, the beneficial effect of IGF-I was diminished by microglial depletion using clodronate-containing liposomes. Interestingly, in the absence of IGF-I, microglial depletion partially prevented cell death without affecting Müller gliosis. These findings strongly suggest a role for microglia-Müller glia crosstalk in neuroprotection. However, a subpopulation of microglial cells appears to promote neurodegeneration in the dystrophic retina. Our findings indicate that beneficial neuroprotective effects may be achieved through strategies that modulate microglial cell responses.

  1. Retinal Arterial Macroaneurysm. A Case Report Macroaneurisma arterial retinal. Presentación de un caso.

    Directory of Open Access Journals (Sweden)

    Aimé Broche Hernández

    2011-08-01

    Full Text Available Retinal macroaneurysms are saccular dilatations of the retinal arteries. They commonly appear in temporary arches, which are found in elderly patients with hypertension and / or generalized vascular disease. They are slightly more frequent in women. In this article we present a case with a macroaneurysm rupture that was treated with laser photocoagulation and evolved favorably.Los macroaneurismas retinianos son dilataciones saculares de las arterias retinianas, con mayor frecuencia en arcadas temporales, que se detectan en pacientes de edad avanzada con hipertensión arterial y/o enfermedad vascular generalizada; son ligeramente más frecuentes en mujeres. Se presenta un caso clínico con ruptura de un macroaneurisma, que fue tratado con fotocoagulación con láser y evolucionó favorablemente.

  2. Possibility of enhanced risk of retinal neovascularization in repeated blood donors: blood donation and retinal alteration

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    Rastmanesh R

    2011-09-01

    Full Text Available Reza RastmaneshDepartment of Clinical Nutrition and Dietetics, Shahid Beheshti University of Medical Sciences, National Nutrition and Food Technology Research Institute, Tehran, IranAbstract: Repeated blood donors manifest clinical, subclinical, and biochemical signs of iron deficiency anemia, have significantly higher erythropoietin and vascular endothelial growth factor (VEGF concentrations, and decreased tissue oxygen saturation, oxygenated tissue hemoglobin, and regional cerebral oxygen saturation. Erythropoietin and VEGF are potent retinal angiogenic factors which may initiate and promote the retinal angiogenesis process independently or simultaneously. Increases in circulating levels of erythropoietin and VEGF are proportionate to the levels of hematocrit, hypoxemia, and tissue hypoxia. It is suggested that higher erythropoietin production following iron deficiency anemia-induced chronic hypoxemia/hypoxia may, hypothetically, enhance the risk of retinal angiogenesis and/or neovascularization, possibly by inducing hypoxia inducible factor-1 alpha, which consequently upregulates genes stimulating angiogenesis, resulting in formation of a new vasculature, possibly by modulation of signal transducer and activator of transcription 3 signaling in the retina. Implications of this hypothesis cover erythropoietin doping, chronic hypoxia, and hypoxemic situations, such as angiogenesis-related cardiac and pulmonary diseases.Keywords: repeated blood donation, erythropoietin, retinal neovascularization, vascular endothelial growth factor, hypoxia

  3. Beta-adrenoceptor-mediated vasodilation of retinal blood vessels is reduced in streptozotocin-induced diabetic rats.

    Science.gov (United States)

    Nakazawa, Taisuke; Sato, Ayumi; Mori, Asami; Saito, Maki; Sakamoto, Kenji; Nakahara, Tsutomu; Ishii, Kunio

    2008-01-01

    We investigated the effects of epinephrine and dopamine on retinal blood vessels in streptozotocin (STZ, 80 mg/kg, i.p.)-treated rats and age-matched control rats to determine whether diabetes mellitus alters the retinal vascular responses to circulating catecholamines. Experiments were performed 6-8 weeks after treatment with STZ or the vehicle. The fundus images were captured with the digital fundus camera system for small animals we developed and diameters of retinal blood vessels contained in the digital images were measured. Epinephrine increased the diameters of retinal blood vessels, but the vasodilator responses were reduced in diabetic rats. Dopamine produced a biphasic retinal vascular response with an initial vasoconstriction followed by a vasodilation. The vasoconstrictor effects of dopamine on retinal arterioles were enhanced in diabetic rats, whereas the difference between the two groups was abolished by treatment with propranolol. The vasodilator effect of isoproterenol, but not of the activator of adenylyl cyclase colforsin, on retinal blood vessels was reduced in diabetic rats. No difference in vasoconstriction of retinal blood vessels to phenylephrine between non-diabetic and diabetic rats was observed. The vasodilator responses of retinal blood vessels to 1,1-dimethyl-4-phenylpiperazinium, a ganglionic nicotinic receptor agonist, were also attenuated in diabetic rats. These results suggest that diabetes mellitus alters the retinal vascular responses to circulating catecholamines and the impairment of vasodilator responses mediated by beta-adrenoceptors contributes to the alteration.

  4. Heritability of retinal vessel diameters and blood pressure

    DEFF Research Database (Denmark)

    Taarnhøj, Nina C B B; Larsen, Michael; Sander, Birgit

    2006-01-01

    PURPOSE: To assess the relative influence of genetic and environmental effects on retinal vessel diameters and blood pressure in healthy adults, as well as the possible genetic connection between these two characteristics. METHODS: In 55 monozygotic and 50 dizygotic same-sex healthy twin pairs......%-80%) for CRAE, 83% (95% CI: 73%-89%) for CRVE, and 61% (95% CI: 44%-73%) for mean arterial blood pressure (MABP). Retinal artery diameter decreased with increasing age and increasing arterial blood pressure. Mean vessel diameters in the population were 165.8 +/- 14.9 microm for CRAE, 246.2 +/- 17.7 microm...... and blood glucose, variations in retinal blood vessel diameters and blood pressure were predominantly attributable to genetic effects. A genetic influence may have a role in individual susceptibility to hypertension and other vascular diseases. The results suggest that retinal vessel diameters...

  5. No evidence for thrombophilia in patients with retinal venous occlusion

    DEFF Research Database (Denmark)

    Kirkegaard, Kirstine; Heegaard, Steffen; Hvas, Anne-Mette

    2016-01-01

    Retinal venous occlusion represents a common retinal disorder that untreated often leads to severely reduced vision. While general risk factors for vascular disease are known to increase the risk of an event, the role of thrombophilia is controversial. The purpose of this systematic review...... was to evaluate the evidence for thrombophilia investigation in patients presenting with retinal venous occlusion. Eligible studies were identified by a MESH-based search in PubMed 11–13 of March 2015. The level of evidence was stated according to the guidelines published by the GRADE working group using three...... synthesis. The majority of studies were small case–control studies, and only one large cohort study was identified. No randomized controlled trials were retrieved. All the studies were categorized as low quality of evidence. Systematic thrombophilia screening in patients presenting with retinal venous...

  6. Wide-field optical coherence tomography based microangiography for retinal imaging

    Science.gov (United States)

    Zhang, Qinqin; Lee, Cecilia S.; Chao, Jennifer; Chen, Chieh-Li; Zhang, Thomas; Sharma, Utkarsh; Zhang, Anqi; Liu, Jin; Rezaei, Kasra; Pepple, Kathryn L.; Munsen, Richard; Kinyoun, James; Johnstone, Murray; van Gelder, Russell N.; Wang, Ruikang K.

    2016-02-01

    Optical coherence tomography angiography (OCTA) allows for the evaluation of functional retinal vascular networks without a need for contrast dyes. For sophisticated monitoring and diagnosis of retinal diseases, OCTA capable of providing wide-field and high definition images of retinal vasculature in a single image is desirable. We report OCTA with motion tracking through an auxiliary real-time line scan ophthalmoscope that is clinically feasible to image functional retinal vasculature in patients, with a coverage of more than 60 degrees of retina while still maintaining high definition and resolution. We demonstrate six illustrative cases with unprecedented details of vascular involvement in retinal diseases. In each case, OCTA yields images of the normal and diseased microvasculature at all levels of the retina, with higher resolution than observed with fluorescein angiography. Wide-field OCTA technology will be an important next step in augmenting the utility of OCT technology in clinical practice.

  7. Retinal oximetry in patients with ischaemic retinal diseases

    DEFF Research Database (Denmark)

    Rilvén, Sandra; Torp, Thomas Lee; Grauslund, Jakob

    2016-01-01

    The retinal oximeter is a new tool for non-invasive measurement of retinal oxygen saturation in humans. Several studies have investigated the associations between retinal oxygen saturation and retinal diseases. In the present systematic review, we examine whether there are associations between...

  8. Vascular Cognitive Impairment.

    Science.gov (United States)

    Dichgans, Martin; Leys, Didier

    2017-02-03

    Cerebrovascular disease typically manifests with stroke, cognitive impairment, or both. Vascular cognitive impairment refers to all forms of cognitive disorder associated with cerebrovascular disease, regardless of the specific mechanisms involved. It encompasses the full range of cognitive deficits from mild cognitive impairment to dementia. In principle, any of the multiple causes of clinical stroke can cause vascular cognitive impairment. Recent work further highlights a role of microinfarcts, microhemorrhages, strategic white matter tracts, loss of microstructural tissue integrity, and secondary neurodegeneration. Vascular brain injury results in loss of structural and functional connectivity and, hence, compromise of functional networks within the brain. Vascular cognitive impairment is common both after stroke and in stroke-free individuals presenting to dementia clinics, and vascular pathology frequently coexists with neurodegenerative pathology, resulting in mixed forms of mild cognitive impairment or dementia. Vascular dementia is now recognized as the second most common form of dementia after Alzheimer's disease, and there is increasing awareness that targeting vascular risk may help to prevent dementia, even of the Alzheimer type. Recent advances in neuroimaging, neuropathology, epidemiology, and genetics have led to a deeper understanding of how vascular disease affects cognition. These new findings provide an opportunity for the present reappraisal of vascular cognitive impairment. We further briefly address current therapeutic concepts.

  9. Metabolic syndrome and central retinal artery occlusion

    Directory of Open Access Journals (Sweden)

    Kosanović-Jaković Natalija

    2005-01-01

    Full Text Available Background. The accumulation of risk factors for central retinal artery occlusion can be seen in a single person and might be explained by the metabolic syndrome. Case report. We presented the case of a 52-year-old man with no light perception in his right eye. The visual loss was monocular and painless, fundoscopy showed central retinal artery occlusion and the laboratory investigation showed the raised erythrocyte sedimentation rate of 105 mm/h and the raised C-reactive protein of 22 mg/l. Specific laboratory investigations and fluorescein angiography excluded the presence of vasculitis, collagen vascular diseases, hypercoagulable state and antiphospholipid syndrome. Conclusion. The patient met all the five of the National Cholesterol Education Program (NCEP criteria for the metabolic syndrome: hypertension, abnormal lipid profile, abnormal glucose metabolism, obesity and hyperuricemia. Measurement of C-reactive protein is useful for the assessment of therapeutic systemic effect on any abnormality in the metabolic syndrome. Individual therapy for all risk factors in the metabolic syndrome is necessary to prevent complications such as cardiovascular, retinal vascular diseases and stroke.

  10. Orthogonal moments for determining correspondence between vessel bifurcations for retinal image registration.

    Science.gov (United States)

    Patankar, Sanika S; Kulkarni, Jayant V

    2015-05-01

    Retinal image registration is a necessary step in diagnosis and monitoring of Diabetes Retinopathy (DR), which is one of the leading causes of blindness. Long term diabetes affects the retinal blood vessels and capillaries eventually causing blindness. This progressive damage to retina and subsequent blindness can be prevented by periodic retinal screening. The extent of damage caused by DR can be assessed by comparing retinal images captured during periodic retinal screenings. During image acquisition at the time of periodic screenings translation, rotation and scale (TRS) are introduced in the retinal images. Therefore retinal image registration is an essential step in automated system for screening, diagnosis, treatment and evaluation of DR. This paper presents an algorithm for registration of retinal images using orthogonal moment invariants as features for determining the correspondence between the dominant points (vessel bifurcations) in the reference and test retinal images. As orthogonal moments are invariant to TRS; moment invariants features around a vessel bifurcation are unaltered due to TRS and can be used to determine the correspondence between reference and test retinal images. The vessel bifurcation points are located in segmented, thinned (mono pixel vessel width) retinal images and labeled in corresponding grayscale retinal images. The correspondence between vessel bifurcations in reference and test retinal image is established based on moment invariants features. Further the TRS in test retinal image with respect to reference retinal image is estimated using similarity transformation. The test retinal image is aligned with reference retinal image using the estimated registration parameters. The accuracy of registration is evaluated in terms of mean error and standard deviation of the labeled vessel bifurcation points in the aligned images. The experimentation is carried out on DRIVE database, STARE database, VARIA database and database provided

  11. Characterization of a spontaneous retinal neovascular mouse model.

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    Eiichi Hasegawa

    Full Text Available BACKGROUND: Vision loss due to vascular disease of the retina is a leading cause of blindness in the world. Retinal angiomatous proliferation (RAP is a subgroup of neovascular age-related macular degeneration (AMD, whereby abnormal blood vessels develop in the retina leading to debilitating vision loss and eventual blindness. The novel mouse strain, neoretinal vascularization 2 (NRV2, shows spontaneous fundus changes associated with abnormal neovascularization. The purpose of this study is to characterize the induction of pathologic angiogenesis in this mouse model. METHODS: The NRV2 mice were examined from postnatal day 12 (p12 to 3 months. The phenotypic changes within the retina were evaluated by fundus photography, fluorescein angiography, optical coherence tomography, and immunohistochemical and electron microscopic analysis. The pathological neovascularization was imaged by confocal microscopy and reconstructed using three-dimensional image analysis software. RESULTS: We found that NRV2 mice develop multifocal retinal depigmentation in the posterior fundus. Depigmented lesions developed vascular leakage observed by fluorescein angiography. The spontaneous angiogenesis arose from the retinal vascular plexus at postnatal day (p15 and extended toward retinal pigment epithelium (RPE. By three months of age, histological analysis revealed encapsulation of the neovascular lesion by the RPE in the photoreceptor cell layer and subretinal space. CONCLUSIONS: The NRV2 mouse strain develops early neovascular lesions within the retina, which grow downward towards the RPE beginning at p15. This retinal neovascularization model mimics early stages of human retinal angiomatous proliferation (RAP and will likely be a useful in elucidating targeted therapeutics for patients with ocular neovascular disease.

  12. Laser photocoagulation for retinal vein occlusion

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    K. A. Mirzabekova

    2015-03-01

    Full Text Available Retinal vein occlusion (RVO is one of the leading causes of permanent vision loss. In adults, central retinal vein occlusion (CRVO occurs in 1.8% while branch retinal vein occlusion (BRVO occurs in 0.2%. Treatment strategy and disease prognosis are determined by RVO type (ischemic/non-ischemic. Despite numerous studies and many current CRVO and BRVO treatment approaches, the management of these patients is still being debated. Intravitreal injections of steroids (triamcinolone acetate, dexamethasone and vascular endothelial growth factor (VEGF inhibitors (bevacizumab, ranibizumab were shown to be fairly effective. However, it is unclear whether anti-VEGF agents are reasonable in ischemic RVOs. Laser photocoagulation remains the only effective treatment of optic nerve head and/or retinal neovascularization. Laser photocoagulation is also indicated for the treatment of macular edema. Both threshold and sub-threshold photocoagulation may be performed. Photocoagulation performed with argon (514 nm, krypton (647 nm, or diode (810 nm laser for macular edema provides similar results (no significant differences. The treatment may be complex and include medication therapy and/or surgery. Medication therapy includes anti-aggregant agents and antioxidants, i.e., emoxypine which may be used in acute RVO as well as in post-thrombotic retinopathy. 

  13. Involvement of Autophagic Pathway in the Progression of Retinal Degeneration in a Mouse Model of Diabetes.

    Science.gov (United States)

    Piano, Ilaria; Novelli, Elena; Della Santina, Luca; Strettoi, Enrica; Cervetto, Luigi; Gargini, Claudia

    2016-01-01

    The notion that diabetic retinopathy (DR) is essentially a micro-vascular disease has been recently challenged by studies reporting that vascular changes are preceded by signs of damage and loss of retinal neurons. As to the mode by which neuronal death occurs, the evidence that apoptosis is the main cause of neuronal loss is far from compelling. The objective of this study was to investigate these controversies in a mouse model of streptozotocin (STZ) induced diabetes. Starting from 8 weeks after diabetes induction there was loss of rod but not of cone photoreceptors, together with reduced thickness of the outer and inner synaptic layers. Correspondingly, rhodopsin expression was downregulated and the scotopic electroretinogram (ERG) is suppressed. In contrast, cone opsin expression and photopic ERG response were not affected. Suppression of the scotopic ERG preceded morphological changes as well as any detectable sign of vascular alteration. Only sparse apoptotic figures were detected by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay and glia was not activated. The physiological autophagy flow was altered instead, as seen by increased LC3 immunostaining at the level of outer plexiform layer (OPL) and upregulation of the autophagic proteins Beclin-1 and Atg5. Collectively, our results show that the streptozotocin induced DR in mouse initiates with a functional loss of the rod visual pathway. The pathogenic pathways leading to cell death develop with the initial dysregulation of autophagy well before the appearance of signs of vascular damage and without strong involvement of apoptosis.

  14. Functional analysis of retinal microglia and their effects on progenitors.

    Science.gov (United States)

    Carter, Debra A; Balasubramaniam, Balini; Dick, Andrew D

    2013-01-01

    The identification of stem/progenitor cells within the retinal neural environment has opened up the possibility of therapy via cellular replacement and/or reprogramming of resident cell populations. Within the neuro-retinal niche, following injury or in disease states (including inflammation and degeneration), cellular responses affect tissue homeostasis, reduce cell density, disrupt tissue architecture, and produce scar formation. Microglia (resident retinal immune cell tissue macrophage) are key to the maintenance of retinal homeostasis and are implicated in responses that may influence the control and behavior of retinal progenitors. Factors to consider in the generation of a transplantable cell resource with good migratory and integrative capacity include their yield, purity, and functional viability. Utilizing human postmortem retina, we have created a research platform to isolate, culture, and characterize adult retinal microglia as well as analyze their effect on retinal progenitors. Here, we describe techniques using magnetic labeled bead cell separation to isolate pure populations of retinal CD133(+) precursor cells and CD11b(+) microglia from primary adult retinal cell suspensions (RCSs), enabling flow cytometric cell phenotypic and qPCR genotypic analysis, as well as functional analysis by real-time ratiometric calcium imaging.

  15. High dietary sodium blunts affects of angiotensin-converting enzyme inhibition on vascular angiotensin I-to-angiotensin II conversion in rats

    NARCIS (Netherlands)

    Kocks, Menno J A; Buikema, Hendrik; Gschwend, Simone; Boomsma, Frans; de Zeeuw, Dick; Navis, Gerjan

    2003-01-01

    High sodium intake blunts the efficacy of angiotensin (Ang)-converting enzyme (ACE) inhibition (ACEi), but the underlying mechanism is incompletely characterized. High sodium has been reported to increase vascular expression and vascular activity of ACE. To investigate whether high-dietary sodium-in

  16. Advanced Coats’ disease treated with intravitreal bevacizumab combined with laser vascular ablation

    Directory of Open Access Journals (Sweden)

    Villegas VM

    2014-05-01

    Full Text Available Victor M Villegas,1 Aaron S Gold,1 Audina M Berrocal,2 Timothy G Murray11Ocular Oncology and Retina, Miami, FL, USA; 2Department of Ophthalmology, Bascom Palmer Eye Institute, Miller School of Medicine, University of Miami, Miami, FL, USAPurpose: To evaluate the impact of intravitreal bevacizumab combined with laser vascular ablation in the management of advanced Coats’ disease presenting with exudative retinal detachment.Methods: This was a retrospective review of 24 children that presented with exudative retinal detachments associated with advanced Coats’ disease. Mean patient age was 62 months (range 9–160 months. Presenting signs included retinal detachment in 24 children (100%, vascular telangiectasia in 24 children (100%, and retinal ischemia in 24 children (100%. Twenty of 24 children presented with elevated, vascular leakage in the fovea (83%. Two children presented with sub-retinal fibrosis associated with presumed long-standing retinal detachment without evidence of rhegmatogenous retinal detachment. Ten patients exhibited vascular alterations in the periphery of the second eye without clinical evidence of exudation. All 24 children were treated with a large-spot-size diode laser directly to areas of abnormal telangiectatic vasculature. All 24 children received intravitreal bevacizumab injection. Results: All 24 children had resolution of exudative retinal detachment, ablation of vascular telangiectasia, and anatomic improvement of the retina. No child exhibited progressive retinal detachment and no eye required enucleation. No cases of neovascular glaucoma were seen. Fellow eyes with peripheral vascular alterations showed no progression to exudative vasculopathy during the observation period. Intravitreal bevacizumab injection was not associated with endophthalmitis or systemically-observed complications.Conclusion: Repetitive intravitreal bevacizumab combined with laser vascular ablation may be utilized effectively

  17. Neuroprotective Effects of Low-Dose Statins in the Retinal Ultrastructure of Hypercholesterolemic Rabbits.

    Science.gov (United States)

    Fernández-Navarro, Judith; Aldea, Pilar; de Hoz, Rosa; Salazar, Juan J; Ramírez, Ana I; Rojas, Blanca; Gallego, Beatriz I; Triviño, Alberto; Tejerina, Teresa; Ramírez, José M

    2016-01-01

    To evaluate the pleiotropic effects to statins, we analyze the qualitative and quantitative retinal changes in hypercholesterolemic rabbits after a low-dosage statin treatment. For this purpose, New Zealand rabbits were split into three groups: control (G0; n = 10), fed a standard diet; hypercholesterolemic (G1; n = 8), fed a 0.5% cholesterol-enriched diet for 8 months; and statins (G2; n = 8), fed a 0.5% cholesterol-enriched diet for 8 months, together with the administration of statin (pravastatin or fluvastatin sodium) at a dose of 2 mg / kg / day each diet. The retinas were analyzed by transmission electron microscopy and immunohistochemistry (glial fibrillary acidic protein). The retinal thickness of nuclear and plexiform layers were quantified in semi-thin sections. The results revealed that the low-statin-treated rabbits in comparison with the hypercholesterolemic group showed: i) a more preserved structure in all retinal layers; ii) a significant reduction in retinal thickness; iii) a decrease in cell death in the nuclear-and ganglion-cell layers; iv) a reduction of hydropic degeneration in the plexiform and nerve-fiber layers; v) a preservation of astrocytes and of the retinal area occupied by them; and vi) a better-preserved retinal vascular structure. Our findings indicate that low doses of statins can prevent retinal degeneration, acting on retinal macroglia, neurons and retinal vessels, despite that hypercholesterolemia remained unchanged. Thus, the pleiotropic effects of the statins may help safeguard the retinal ultrastructure.

  18. [Genetic diagnostic testing in inherited retinal dystrophies].

    Science.gov (United States)

    Kohl, S; Biskup, S

    2013-03-01

    Inherited retinal dystrophies are clinically and genetically highly heterogeneous. They can be divided according to the clinical phenotype and course of the disease, as well as the underlying mode of inheritance. Isolated retinal dystrophies (i.e., retinitis pigmentosa, Leber's congenital amaurosis, cone and cone-rod dystrophy, macular dystrophy, achromatopsia, congenital stationary nightblindness) and syndromal forms (i.e., Usher syndrome, Bardet-Biedl syndrome) can be differentiated. To date almost 180 genes and thousands of distinct mutations have been identified that are responsible for the different forms of these blinding illnesses. Until recently, there was no adequate diagnostic genetic testing available. With the development of the next generation sequencing technologies, a comprehensive genetic screening analysis for all known genes for inherited retinal dystrophies has been established at reasonable costs and in appropriate turn-around times. Depending on the primary clinical diagnosis and the presumed mode of inheritance, different diagnostic panels can be chosen for genetic testing. Statistics show that in 55-80 % of the cases the genetic defect of the inherited retinal dystrophy can be identified with this approach, depending on the initial clinical diagnosis. The aim of any genetic diagnostics is to define the genetic cause of a given illness within the affected patient and family and thereby i) confirm the clinical diagnosis, ii) provide targeted genetic testing in family members, iii) enable therapeutic intervention, iv) give a prognosis on disease course and progression and v) in the long run provide the basis for novel therapeutic approaches and personalised medicine.

  19. [Muscular Dystrophies Involving the Retinal Function].

    Science.gov (United States)

    Jägle, H

    2016-03-01

    Muscular dystrophies are rare disorders, with an incidence of approx. 20 in 100 000. Some dystrophies also affect retinal or optic nerve function. In such cases, the ophthalmological findings may be critical for differential diagnosis or patient counseling. For example in Duchenne muscular dystrophy, where the alteration in retinal function seems to reflect cerebral involvement. Other important forms are mitochondrial and metabolic disorders, such as the Kearns-Sayre syndrome and the Refsum syndrome. Molecular genetic analysis has become a major tool for differential diagnosis, but may be complex and demanding. This article gives an overview of major muscular dystrophies involving retinal function and their genetic origin, in order to guide differential diagnosis.

  20. Marfan Syndrome Presenting with Bilateral Retinal Detachment

    Directory of Open Access Journals (Sweden)

    Subrata Chakrabarti

    2014-02-01

    Full Text Available Marfan syndrome is an autosomal dominant systemic disorder of the connective tissue. Marfan syndrome affects most organs and tissues, especially the skeleton, lungs, eyes, heart, and the large blood vessels. Eye involvement may be in the form of retinal detachment which is a potentially dangerous manifestation for its sight threatening nature .We report a case where a 17 year old male developed sudden blindness due to spontaneous bilateral retinal detachment. Examination revealed features of Marfan syndrome and was stamped as a case of Marfan syndrome by Ghent criteria . The point to stress upon is that a young male developing spontaneous retinal detachment, a diagnosis of underlying Marfan syndrome should be kept in mind if appropriate clinical stigmata are present. [Natl J Med Res 2014; 4(1.000: 104-105

  1. Progressive outer retinal necrosis (PORN) in AIDS patients: a different appearance of varicella-zoster retinitis.

    Science.gov (United States)

    Pavesio, C E; Mitchell, S M; Barton, K; Schwartz, S D; Towler, H M; Lightman, S

    1995-01-01

    Retinal infections caused by the varicella-zoster virus (VZV) have been reported in immunocompetent and immunocompromised individuals. Two cases of a VZV-related retinitis are described with the characteristic features of the recently described progressive outer retinal necrosis (PORN) syndrome. Both patients suffered from the acquired immunodeficiency syndrome (AIDS) with greatly reduced peripheral blood CD4+ T lymphocyte counts, and presented with macular retinitis without vitritis. The disease was bilateral in one case and unilateral in the other. The clinical course was rapidly progressive with widespread retinal involvement and the development of rhegmatogenous retinal detachment with complete loss of vision in the affected eyes despite intensive intravenous antiviral therapy. VZV DNA was identified in vitreous biopsies, by molecular techniques based on the polymerase chain reaction (PCR), in both patients. At present, the use of very high-dose intravenous acyclovir may be the best therapeutic option in these patients for whom the visual prognosis is poor. Intravitreal antiviral drugs could also contribute to the management of these cases.

  2. Retinal Vasculitis in Anti-Synthetase Syndrome.

    Science.gov (United States)

    Donovan, Christopher P; Pecen, Paula E; Baynes, Kimberly; Ehlers, Justis P; Srivastava, Sunil K

    2016-09-01

    A 31-year-old woman with a history of anti-synthetase syndrome-related myositis and interstitial lung disease presented with acute-onset blurry vision and rash on her hands and feet. Visual acuity was hand motion in her right eye and 20/40 in her left eye. Dilated fundus exam showed extensive retinal vasculitis, diffuse intraretinal hemorrhages, and subretinal fluid. Optical coherence tomography revealed significant macular thickening, and fluorescein angiography revealed vascular leakage with peripheral nonperfusion. Aggressive systemic immunosuppression was initiated, with gradual resolution of her disease during 8 months of follow-up. [Ophthalmic Surg Lasers Imaging Retina. 2016;47:874-879.].

  3. Ocular hemodynamics in patients with rhegmatogenous retinal detachment

    Directory of Open Access Journals (Sweden)

    N. H. Zavgorodnya

    2014-10-01

    Full Text Available Aim. In case of retinal detachment atrophic processes lead to irreversible loss of functions within 4–6 days, it happens on underlying low ocular blood flow. In order to evaluate the degree of violation of regional hemodynamics in patients with retinal detachment two groups of patients were examined: the main group (52 patients with rhegmatogenous retinal detachment and the control group (24 myopic patients with lattice form of peripheral chorioretinal dystrophy. Methods and results. Doppler and reography results had been compared, significant decrease of blood flow in patients with retinal detachment was found. No differences between affected and fellow eye in these patients, close negative correlation between the level of ocular blood flow and the degree of myopia in the control group. Conclusion. This demonstrates the feasibility of actions to improve regional blood flow in patients operated on for retinal detachment.

  4. Interruption of Wnt signaling in Muller cells ameliorates ischemia-induced retinal neovascularization.

    Directory of Open Access Journals (Sweden)

    Kelu Kevin Zhou

    Full Text Available Retinal Müller cells are major producers of inflammatory and angiogenic cytokines which contribute to diabetic retinopathy (DR. Over-activation of the Wnt/β-catenin pathway has been shown to play an important pathogenic role in DR. However, the roles of Müller cell-derived Wnt/β-catenin signaling in retinal neovascularization (NV and DR remain undefined. In the present study, mice with conditional β-catenin knockout (KO in Müller cells were generated and subjected to oxygen-induced retinopathy (OIR and streptozotocin (STZ-induced diabetes. Wnt signaling was evaluated by measuring levels of β-catenin and expression of its target genes using immunoblotting. Retinal vascular permeability was measured using Evans blue as a tracer. Retinal NV was visualized by angiography and quantified by counting pre-retinal nuclei. Retinal pericyte loss was evaluated using retinal trypsin digestion. Electroretinography was performed to examine visual function. No abnormalities were detected in the β-catenin KO mice under normal conditions. In OIR, retinal levels of β-catenin and VEGF were significantly lower in the β-catenin KO mice than in littermate controls. The KO mice also had decreased retinal NV and vascular leakage in the OIR model. In the STZ-induced diabetic model, disruption of β-catenin in Müller cells attenuated over-expression of inflammatory cytokines and ameliorated pericyte dropout in the retina. These findings suggest that Wnt signaling activation in Müller cells contributes to retinal NV, vascular leakage and inflammation and represents a potential therapeutic target for DR.

  5. A Case of Branch Retinal Artery Occlusion following Uneventful Phacoemulsification

    Directory of Open Access Journals (Sweden)

    Daniel Dragnev

    2013-03-01

    Full Text Available We would like to present a case of branch retinal artery occlusion following uneventful phacoemulsification, possibly caused by sub-Tenon's anaesthesia. There were no predisposing general health problems. There are two possible mechanisms: (1 mechanical effect of the bolus anaesthetic; (2 pharmacologically mediated changes in the vascular calibre. The latter mechanism is much more probable, because of the vasoconstrictive properties of both medications used. This is the first reported case of branch retinal artery occlusion after sub-Tenon's anaesthesia with preservative-free medications.

  6. Vascular quality of care pilot study: how admission to a vascular surgery service affects evidence-based pharmacologic risk factor modification in patients with lower extremity peripheral arterial disease

    Directory of Open Access Journals (Sweden)

    Steenhof N

    2014-06-01

    Full Text Available Naomi Steenhof,1,2 Francesca Le Piane,1 Kori Leblanc,1–3 Naomi R Eisenberg,4 Yvonne Kwan,1 Christine Malmberg,1,6 Alexandra Papadopoulos,5,7 Graham Roche-Nagle4,7,8 1Department of Pharmacy, University Health Network, 2Leslie Dan Faculty of Pharmacy, University of Toronto, 3Centre for Innovation in Complex Care, University Health Network, 4Division of Vascular Surgery, University Health Network, 5Faculty of Nursing, University of Toronto, Toronto, ON, 6Victoria General Hospital, Vancouver Island Health Authority, Victoria, BC, 7Peter Munk Cardiac Centre, University Health Network, 8Faculty of Medicine, University of Toronto, Toronto, ON, Canada Background: Peripheral arterial disease (PAD guidelines recommend aggressive risk factor modification to improve cardiovascular outcomes. Recommended pharmacologic therapies include antiplatelets, angiotensin converting enzyme (ACE inhibitors, and HMG-CoA-reductase inhibitors (statins. Purpose: We studied the degree to which patient admission to a vascular surgery service increased the use of these therapies. Patients and methods: The authors conducted a retrospective chart review of 150 patients with PAD admitted to the vascular surgery service at a large Canadian tertiary care hospital. The use of recommended pharmacologic therapies at the time of admission and discharge were compared. A multidisciplinary clinical team established criteria by which patients were deemed ineligible to receive any of the recommended therapies. Angiotensin receptor blockers (ARBs were considered an alternative to ACE inhibitors. Results: Prior to hospital admission, 64% of patients were on antiplatelet therapy, 67% were on an ACE inhibitor or ARB, and 71% were on a statin. At the time of discharge, 91% of patients were on an antiplatelet (or not, with an acceptable reason, 77% were on an ACE inhibitor or an ARB (or not, with an acceptable reason, and 85% were on a statin (or not, with an acceptable reason. While new

  7. Retinal Remodeling: Concerns, Emerging Remedies, and Future Prospects

    Directory of Open Access Journals (Sweden)

    Vidhyasankar eKrishnamoorthy

    2016-02-01

    Full Text Available Deafferentation results not only in sensory loss, but also in a variety of alterations in the postsynaptic circuitry. These alterations may have detrimental impact on potential treatment strategies. Progressive loss of photoreceptors in retinal degenerative diseases, such as retinitis pigmentosa and age-related macular degeneration, leads to several changes in the remnant retinal circuitry. Müller glial cells undergo hypertrophy and form a glial seal. The second- and third-order retinal neurons undergo morphological, biochemical and physiological alterations. A result of these alterations is that retinal ganglion cells (RGCs, the output neurons of the retina, become hyperactive and exhibit spontaneous, oscillatory bursts of spikes. This aberrant electrical activity degrades the signal-to-noise ratio in RGC responses, and thus the quality of information they transmit to the brain. These changes in the remnant retina, collectively termed retinal remodeling, pose challenges for genetic, cellular and bionic approaches to restore vision. It is therefore crucial to understand the nature of retinal remodeling, how it affects the ability of remnant retina to respond to novel therapeutic strategies, and how to ameliorate its effects. In this article, we discuss these topics, and suggest that the pathological state of the retinal output following photoreceptor loss is reversible, and therefore, amenable to restorative strategies.

  8. Light activation of the isomerization and deprotonation of the protonated Schiff base retinal.

    Science.gov (United States)

    Kubli-Garfias, Carlos; Salazar-Salinas, Karim; Perez-Angel, Emily C; Seminario, Jorge M

    2011-10-01

    We perform an ab initio analysis of the photoisomerization of the protonated Schiff base of retinal (PSB-retinal) from 11-cis to 11-trans rotating the C10-C11=C12-C13 dihedral angle from 0° (cis) to -180° (trans). We find that the retinal molecule shows the lowest rotational barrier (0.22 eV) when its charge state is zero as compared to the barrier for the protonated molecule which is ∼0.89 eV. We conclude that rotation most likely takes place in the excited state of the deprotonated retinal. The addition of a proton creates a much larger barrier implying a switching behavior of retinal that might be useful for several applications in molecular electronics. All conformations of the retinal compound absorb in the green region with small shifts following the dihedral angle rotation; however, the Schiff base of retinal (SB-retinal) at trans-conformation absorbs in the violet region. The rotation of the dihedral angle around the C11=C12 π-bond affects the absorption energy of the retinal and the binding energy of the SB-retinal with the proton at the N-Schiff; the binding energy is slightly lower at the trans-SB-retinal than at other conformations of the retinal.

  9. Progressive outer retinal necrosis-like retinitis in immunocompetent hosts.

    Science.gov (United States)

    Chawla, Rohan; Tripathy, Koushik; Gogia, Varun; Venkatesh, Pradeep

    2016-08-10

    We describe two young immunocompetent women presenting with bilateral retinitis with outer retinal necrosis involving posterior pole with centrifugal spread and multifocal lesions simulating progressive outer retinal necrosis (PORN) like retinitis. Serology was negative for HIV and CD4 counts were normal; however, both women were on oral steroids at presentation for suspected autoimmune chorioretinitis. The retinitis in both eyes responded well to oral valaciclovir therapy. However, the eye with the more fulminant involvement developed retinal detachment with a loss of vision. Retinal atrophy was seen in the less involved eye with preservation of vision. Through these cases, we aim to describe a unique evolution of PORN-like retinitis in immunocompetent women, which was probably aggravated by a short-term immunosuppression secondary to oral steroids.

  10. Branch Retinal Vein Occlusion and Its Management

    Institute of Scientific and Technical Information of China (English)

    Desmond; Archer

    1992-01-01

    The natural course of Branch Retinal Vein Occlusion is determined by the site and completeness of the occlusion, the integrity of arterial perfusion to the affected sector and the efficiency of the developing collateral circulation. Most patients with tributary vein occlusion have some capillary fall out and microvascular incompetence in the distribution of the affected retina and vision is significantly compromised in over 50% of patients who have either chronic macular oedema or ischemia involving the...

  11. PLVAP in diabetic retinopathy: A gatekeeper of angiogenesis and vascular permeability

    NARCIS (Netherlands)

    Wiśniewska-Kruk, J.

    2014-01-01

    Nowadays, approximately 4 million people worldwide experience blindness or severe vision loss caused by diabetic retinopathy. Diabetic retinopathy is a multifactorial disease that can progress from minor changes in vascular permeability, into a proliferative retinal disorder. The increasing incidenc

  12. The effects of Δ9-Tetrahydrocannabinole treatment on gonadal micro-vascularization and affected fertility examined by SEM and 3D-morphometry

    Science.gov (United States)

    Erlbacher, K. M. T.; Minnich, B.

    2015-10-01

    The present study focuses on the effects of Δ9-tetrahydrocannabinol (THC) on the reproductive system in nude rats with special emphasis on how Δ9-THC impacts the vascularization of testes which in turn indirectly influences fertility. Basically, Δ9-tetrahydrocannabinol (THC) causes not only negative (psychoactive) effects in the human body as cannabinole administration in medical use (dose-dependent) offers multiple new treatment opportunities such as pain relief or containment of various cancers. Concerning the reproductive system it strongly influences CB-receptors along the hypothalamic-pituitary-gonadal axis resulting in reduced plasma testosterone levels. There is also altered sperm quality parameters reported such as sperm motility or sperm count. On the other hand Δ9-THC effects endothelial growth factors (VEGF, Ang-1 etc.) respectively acts on their specific receptors which in turn modify angiogenesis and vascularization of tissues and organs (e.g. tumorous tissues). This leads to new therapeutical strategies in the suppression of various cancers by inhibiting (neo-)vascularization and in turn famishment of tumorous tissues (lack of nutrition supply). Here we studied the micro-vascularization of gonads in a long-term THC-treated nude rat model by vascular corrosion casting, SEM and 3D-morphometry.

  13. Cyr61 induces the expression of monocyte chemoattractant protein-1 via the integrin ανβ3, FAK, PI3K/Akt, and NF-κB pathways in retinal vascular endothelial cells.

    Science.gov (United States)

    You, Jian-Jang; Yang, Chang-Hao; Yang, Chung-May; Chen, Muh-Shy

    2014-01-01

    Diabetes causes a number of metabolic and physiological abnormalities in the retina. Many of the molecular and physiological abnormalities that develop during diabetic retinopathy are due to inflammation. Monocyte chemoattractant protein-1 (MCP-1) is an important factor involved in diabetic retinopathy. In a previous study, we found that cysteine-rich 61 (Cyr61), an important angiogenic factor, also plays an important role in diabetic retinopathy. In addition to the direct effects of Cyr61, we observed that Cyr61 can induce the expression of MCP-1. However, the mechanism through which this occurs is not completely understood in chorioretinal vascular endothelial cells. We therefore investigated the effects of Cyr61 on MCP-1 expression in this cell type. Cyr61 stimulated the expression of MCP-1 at the mRNA, protein, and secreted protein levels in a dose-dependent and time-dependent manner. Both total MCP-1 levels and secreted MCP-1 levels were attenuated during the response to Cyr61 stimulation by pretreatment with integrin ανβ3-blocking antibodies, a FAK inhibitor (PF573228), a PI3K inhibitor (LY294002), and an Akt inhibitor (A6730). Electrophoretic mobility shift assays revealed that the above inhibitors suppressed the activation of NF-κB. Additionally, deletion of the NF-κB-binding element in the MCP-1 gene promoter led to a decrease in expression in luciferase reporter assays. These results show that the induction of MCP-1 by Cyr61 is mediated through the activation of the integrin ανβ3, FAK, PI3K/Akt, and IKK/NF-κB pathways in chorioretinal vascular endothelial cells.

  14. Therapeutic efficacy of melatonin in reducing retinal damage in an experimental model of early type 2 diabetes in rats.

    Science.gov (United States)

    Salido, Ezequiel M; Bordone, Melina; De Laurentiis, Andrea; Chianelli, Mónica; Keller Sarmiento, María Inés; Dorfman, Damián; Rosenstein, Ruth E

    2013-03-01

    Diabetic retinopathy (DR) is a leading cause of acquired blindness in adults, mostly affected by type 2 diabetes mellitus (T2DM). We have developed an experimental model of early T2DM in adult rats which mimics some features of human T2DM at its initial stages and provokes significant retinal alterations. The aim of this work was to analyze the effect of melatonin on retinal changes induced by the moderate metabolic derangement. For this purpose, adult male Wistar rats received a control diet or 30% sucrose in the drinking water. Three weeks after this treatment, animals were injected with vehicle or streptozotocin (STZ, 25 mg/kg). One day or 3 wk after vehicle or STZ injection, animals were subcutaneously implanted with a pellet of melatonin. Fasting and postprandial glycemia, and glucose, and insulin tolerance tests were analyzed. At 12 wk of treatment, animals which received a sucrose-enriched diet and STZ showed significant differences in metabolic tests, as compared with control groups. Melatonin, which did not affect glucose metabolism in control or diabetic rats, prevented the decrease in the electroretinogram a-wave, b-wave, and oscillatory potential amplitude, and the increase in retinal lipid peroxidation, NOS activity, TNFα, Müller cells glial fibrillary acidic protein, and vascular endothelial growth factor levels. In addition, melatonin prevented the decrease in retinal catalase activity. These results indicate that melatonin protected the retina from the alterations observed in an experimental model of DR associated with type 2 diabetes.

  15. [Vascular dementia

    NARCIS (Netherlands)

    Leeuw, H.F. de; Gijn, J. van

    2004-01-01

    Vascular dementia is one of the most frequently occurring dementia syndromes. Its prevalence is about 5% among subjects above 85 years of age. Elevated blood pressure and atherosclerosis are the most important risk factors. According to international criteria, vascular dementia usually occurs within

  16. Bioelectronic retinal prosthesis

    Science.gov (United States)

    Weiland, James D.

    2016-05-01

    Retinal prosthesis have been translated to clinical use over the past two decades. Currently, two devices have regulatory approval for the treatment of retinitis pigmentosa and one device is in clinical trials for treatment of age-related macular degeneration. These devices provide partial sight restoration and patients use this improved vision in their everyday lives to navigate and to detect large objects. However, significant vision restoration will require both better technology and improved understanding of the interaction between electrical stimulation and the retina. In particular, current retinal prostheses do not provide peripheral visions due to technical and surgical limitations, thus limiting the effectiveness of the treatment. This paper reviews recent results from human implant patients and presents technical approaches for peripheral vision.

  17. Clinical Trials in Branch Retinal Vein Occlusion

    Science.gov (United States)

    Panakanti, Tandava Krishnan; Chhablani, Jay

    2016-01-01

    Branch retinal vein occlusion (BRVO) is the second most common retinal vascular disorder. The management of macular edema has changed considerably over time. The laser is considered the gold standard treatment for over two decades. However, visual recovery with laser is usually slow and incomplete. The advent of intravitreal agents, specifically anti-vascular endothelial growth factors (VEGF) have heralded a new era which promises rapid recovery of vision and quality of vision. Randomized clinical trials have reported optimal results with anti-VEGF agents (ranibizumab, bevacizumab, and aflibercept) compared to laser therapy or steroids. However, nearly 50% of the patients require repeat intravitreal anti-VEGF therapy up to 4 years after initiating therapy to sustain the visual gains. The adverse events (systemic and ocular) of these agents are minimal. Monotherapy with anti-VEGF agents have been found to provide better results than any combination with laser. This review article summarizes evidence from randomized controlled trials evaluating treatment options for the treatment of macular edema secondary to BRVO with a special focus on anti-VEGF therapy. PMID:26957837

  18. Clinical trials in branch retinal vein occlusion

    Directory of Open Access Journals (Sweden)

    Tandava Krishnan Panakanti

    2016-01-01

    Full Text Available Branch retinal vein occlusion (BRVO is the second most common retinal vascular disorder. The management of macular edema has changed considerably over time. The laser is considered the gold standard treatment for over two decades. However, visual recovery with laser is usually slow and incomplete. The advent of intravitreal agents, specifically anti-vascular endothelial growth factors (VEGF have heralded a new era which promises rapid recovery of vision and quality of vision. Randomized clinical trials have reported optimal results with anti-VEGF agents (ranibizumab, bevacizumab, and aflibercept compared to laser therapy or steroids. However, nearly 50% of the patients require repeat intravitreal anti-VEGF therapy up to 4 years after initiating therapy to sustain the visual gains. The adverse events (systemic and ocular of these agents are minimal. Monotherapy with anti-VEGF agents have been found to provide better results than any combination with laser. This review article summarizes evidence from randomized controlled trials evaluating treatment options for the treatment of macular edema secondary to BRVO with a special focus on anti-VEGF therapy.

  19. Low dietary protein intake during pregnancy differentially affects mitochondrial copy number in stromal vascular cells from subcutaneous versus visceral adipose tissue in the offspring

    Science.gov (United States)

    The present study examined the influence of protein intake during pregnancy on mitochondrial metabolism in stromal vascular cells from subcutaneous (SVSu) and visceral (SVVi) adipose tissue of offspring fed a high fat diet. Obese-prone Sprague-Dawley rats were fed diets containing either 8% or 20% p...

  20. Retinal flow cytometer.

    Science.gov (United States)

    Alt, C; Veilleux, I; Lee, H; Pitsillides, C M; Côté, D; Lin, C P

    2007-12-01

    The in vivo flow cytometer is an instrument capable of continuous, real-time monitoring of fluorescently labeled cells in the circulation without the need to draw blood samples. However, the original system probes a single vessel in the mouse ear; the small sample volume limits the sensitivity of the technique. We describe an in vivo retinal flow cytometer that simultaneously probes five artery-vein pairs in the mouse eye by circularly scanning a small laser spot rapidly around the optic nerve head. We demonstrate that the retinal flow cytometer detects about five times more cells per minute than the original in vivo flow cytometer does in the ear.

  1. Safranal, a saffron constituent, attenuates retinal degeneration in P23H rats.

    Directory of Open Access Journals (Sweden)

    Laura Fernández-Sánchez

    Full Text Available Saffron, an extract from Crocus sativus, has been largely used in traditional medicine for its antiapoptotic and anticarcinogenic properties. In this work, we investigate the effects of safranal, a component of saffron stigmas, in attenuating retinal degeneration in the P23H rat model of autosomal dominant retinitis pigmentosa. We demonstrate that administration of safranal to homozygous P23H line-3 rats preserves both photoreceptor morphology and number. Electroretinographic recordings showed higher a- and b-wave amplitudes under both photopic and scotopic conditions in safranal-treated versus non-treated animals. Furthermore, the capillary network in safranal-treated animals was preserved, unlike that found in untreated animals. Our findings indicate that dietary supplementation with safranal slows photoreceptor cell degeneration and ameliorates the loss of retinal function and vascular network disruption in P23H rats. This work also suggests that safranal could be potentially useful to retard retinal degeneration in patients with retinitis pigmentosa.

  2. Safranal, a saffron constituent, attenuates retinal degeneration in P23H rats.

    Science.gov (United States)

    Fernández-Sánchez, Laura; Lax, Pedro; Esquiva, Gema; Martín-Nieto, José; Pinilla, Isabel; Cuenca, Nicolás

    2012-01-01

    Saffron, an extract from Crocus sativus, has been largely used in traditional medicine for its antiapoptotic and anticarcinogenic properties. In this work, we investigate the effects of safranal, a component of saffron stigmas, in attenuating retinal degeneration in the P23H rat model of autosomal dominant retinitis pigmentosa. We demonstrate that administration of safranal to homozygous P23H line-3 rats preserves both photoreceptor morphology and number. Electroretinographic recordings showed higher a- and b-wave amplitudes under both photopic and scotopic conditions in safranal-treated versus non-treated animals. Furthermore, the capillary network in safranal-treated animals was preserved, unlike that found in untreated animals. Our findings indicate that dietary supplementation with safranal slows photoreceptor cell degeneration and ameliorates the loss of retinal function and vascular network disruption in P23H rats. This work also suggests that safranal could be potentially useful to retard retinal degeneration in patients with retinitis pigmentosa.

  3. Dexamethasone Implant (Ozurdex in a Case with Unilateral Simultaneous Central Retinal Vein and Branch Retinal Artery Occlusion

    Directory of Open Access Journals (Sweden)

    Taylan Ozturk

    2015-02-01

    Full Text Available Simultaneous branch retinal artery and vein occlusion is a rare condition that may cause severe visual loss, and its treatment is often unrewarding. Herein, we report a case with simultaneous central retinal vein and branch retinal artery occlusion; it was successfully treated with a single dexamethasone intravitreal implant. The affected eye attained a visual acuity level of 20/25 from the visual acuity of hand motions at presentation with a residual, but relatively diminished, altitudinal scotoma during a follow-up period of 6 months.

  4. Latin American Consensus on Retinal Vein Occlusion

    Directory of Open Access Journals (Sweden)

    Francisco J. Rodriguez

    2016-01-01

    Full Text Available The introduction of anti-VEGF agents has allowed unprecedented progress in the management and treatment of ophthalmologic conditions characterized by an increased vascular permeability and intraocular neovascularization. One of these conditions is retinal vein occlusion (RVO.  RVO is one of the most common causes of reduced vision due to retinal vascular disease. Without timely treatment, macular edema, macular ischemia, neovascularization and other potential sequelae of RVO can lead to photoreceptor cell death and consequently to irreversible vision loss.   Treatments for this indication that have been recently approved by several regulatory agencies throughout the world include: the VEGF inhibitor ranibizumab (Lucentis, Genentech, the VEGF and placental growth factor inhibitor aflibercept (Eylea, Regeneron Pharmaceuticals and Bayer HealthCare, and a slow release intravitreal implant of dexamethasone (Ozurdex, Allergan. In addition bevacizumab (Avastin, Genentech has been used extensively in an off-label manner.   These new treatments allow us to preserve vision for many RVO patients who could not have expected such favorable results just 5 or 6 years ago. However, not every treatment is effective for every patient, and whether one option is superior to another or a combination of options is superior to monotherapy, have yet to be definitively determined.   A growing body of literature with strong evidence supports the use of these new treatments. However, in several instances the literature is not conclusive to support unified management of RVO. This document is a summary analysis on RVO assembled by a group of specialists summoned by the Pan-American Vitreo-Retinal Society (SPRV to participate in this Latin American consensus.

  5. Exome sequencing extends the phenotypic spectrum for ABHD12 mutations: from syndromic to nonsyndromic retinal degeneration

    NARCIS (Netherlands)

    Nishiguchi, K.M.; Avila-Fernandez, A.; Huet, R.A.C. van; Corton, M.; Perez-Carro, R.; Martin-Garrido, E.; Lopez-Molina, M.I.; Blanco-Kelly, F.; Hoefsloot, L.H.; Zelst-Stams, W.A.G. van; Garcia-Ruiz, P.J.; Val, J. Del; Gioia, S.A. Di; Klevering, B.J.; Warrenburg, B.P.C. van de; Vazquez, C.; Cremers, F.P.M.; Garcia-Sandoval, B.; Hoyng, C.B.; Collin, R.W.J.; Rivolta, C.; Ayuso, C.

    2014-01-01

    OBJECTIVE: To identify the genetic causes underlying autosomal recessive retinitis pigmentosa (arRP) and to describe the associated phenotype. DESIGN: Case series. PARTICIPANTS: Three hundred forty-seven unrelated families affected by arRP and 33 unrelated families affected by retinitis pigmentosa (

  6. Vascular compression syndromes.

    Science.gov (United States)

    Czihal, Michael; Banafsche, Ramin; Hoffmann, Ulrich; Koeppel, Thomas

    2015-11-01

    Dealing with vascular compression syndromes is one of the most challenging tasks in Vascular Medicine practice. This heterogeneous group of disorders is characterised by external compression of primarily healthy arteries and/or veins as well as accompanying nerval structures, carrying the risk of subsequent structural vessel wall and nerve damage. Vascular compression syndromes may severely impair health-related quality of life in affected individuals who are typically young and otherwise healthy. The diagnostic approach has not been standardised for any of the vascular compression syndromes. Moreover, some degree of positional external compression of blood vessels such as the subclavian and popliteal vessels or the celiac trunk can be found in a significant proportion of healthy individuals. This implies important difficulties in differentiating physiological from pathological findings of clinical examination and diagnostic imaging with provocative manoeuvres. The level of evidence on which treatment decisions regarding surgical decompression with or without revascularisation can be relied on is generally poor, mostly coming from retrospective single centre studies. Proper patient selection is critical in order to avoid overtreatment in patients without a clear association between vascular compression and clinical symptoms. With a focus on the thoracic outlet-syndrome, the median arcuate ligament syndrome and the popliteal entrapment syndrome, the present article gives a selective literature review on compression syndromes from an interdisciplinary vascular point of view.

  7. Retinal vessel calibre and micro- and macrovascular complications in type 1 diabetes

    DEFF Research Database (Denmark)

    Grauslund, J; Hodgson, L; Kawasaki, R

    2009-01-01

    and a standardised protocol. Associations between retinal vascular calibre and micro- and macrovascular complications were examined after adjusting for confounding clinical characteristics. RESULTS: Retinal photographs were gradable for 188 of 208 patients (90.3%). The median age and duration of diabetes...... for patients with gradable photos were 57.9 and 42 years, respectively. After multivariate adjustments, individuals with narrower retinal arterioles were more likely to have nephropathy (OR 2.17, 95% CI 1.29-3.68, per SD decrease in CRAE) and macrovascular disease (OR 3.17, 95% CI 1.59-6.34, per SD decrease...

  8. Drugs affecting the eye.

    Science.gov (United States)

    Taylor, F

    1985-08-01

    This discussion reviews drugs that affect the eye, including antihyperglycemic agents; corticosteroids; antirheumatic drugs (quinolines, indomethacin, and allopurinol); psychiatric drugs (phenothiazine, thioridazine, and chlorpromazine); drugs used in cardiology (practolol, amiodarone, and digitalis gylcosides); drugs implicated in optic neuritis and atrophy, drugs with an anticholinergic action; oral contraceptives (OCs); and topical drugs and systemic effects. Refractive changes, either myopic or hypermetropic, can occur as a result of hyperglycemia, and variation in vision is sometimes a presenting symptom in diabetes mellitus. If it causes a change in the refraction, treatment of hyperglycemia almost always produces a temporary hypermetropia. A return to the original refractive state often takes weeks, sometimes months. There is some evidence that patients adequately treated with insulin improve more rapidly than those taking oral medication. Such patients always should be referred for opthalmological evaluation as other factors might be responsible, but it might not be possible to order the appropriate spectacle correction for some time. The most important ocular side effect of the systemic adiministration of corticosteroids is the formation of a posterior subcapsular cataract. Glaucoma also can result from corticosteroids, most often when they are applied topically. Corticosteroids have been implicated in the production of benign intracranial hypertension, which is paradoxical because they also are used in its treatment. The most important side effect of drugs such as chloroquine and hydroxychloroquine is an almost always irreversible maculopathy with resultant loss of central vision. Corneal and retinal changes similar to those caused by the quinolines have been reported with indomethacin, but there is some question about a cause and effect relationship. The National Registry of Drug Induced Ocular Side Effects in the US published 30 case histories of

  9. Retinal locus for scanning text.

    Science.gov (United States)

    Timberlake, George T; Sharma, Manoj K; Grose, Susan A; Maino, Joseph H

    2006-01-01

    A method of mapping the retinal location of text during reading is described in which text position is plotted cumulatively on scanning laser ophthalmoscope retinal images. Retinal locations that contain text most often are the brightest in the cumulative plot, and locations that contain text least often are the darkest. In this way, the retinal area that most often contains text is determined. Text maps were plotted for eight control subjects without vision loss and eight subjects with central scotomas from macular degeneration. Control subjects' text maps showed that the fovea contained text most often. Text maps of five of the subjects with scotomas showed that they used the same peripheral retinal area to scan text and fixate. Text maps of the other three subjects with scotomas showed that they used separate areas to scan text and fixate. Retinal text maps may help evaluate rehabilitative strategies for training individuals with central scotomas to use a particular retinal area to scan text.

  10. Learning about Retinitis Pigmentosa

    Science.gov (United States)

    ... that detect light). Photoreceptor cells capture and process light helping us to see. As these cells breakdown and die, patients experience progressive vision loss. The most common feature of all forms of RP is a ... cells that detect dim light) and cones (retinal cells that detect light and ...

  11. Retinal vein occlusion

    Science.gov (United States)

    ... decrease the risk of retinal vein occlusion. These measures include: Eating a low-fat diet Getting regular exercise Maintaining an ideal weight Not smoking Aspirin or other blood thinners may help prevent blockages in the other eye. Controlling diabetes may ...

  12. Nanomaterials and Retinal Toxicity

    Science.gov (United States)

    The neuroretina should be considered as a potential site of nanomaterial toxicity. Engineered nanomaterials may reach the retina through three potential routes of exposure including; intra­ vitreal injection of therapeutics; blood-borne delivery in the retinal vasculature an...

  13. vascular hemiplegia

    OpenAIRE

    Voto Bernales, Jorge; Facultad de Medicina, Universidad Nacional Mayor de San Marcos, Lima, Perú

    2014-01-01

    The vascular hemiplegia is the functional disorder of a lateral half of the body produced by alterations of cerebral vessels. Should review the concepts of this common condition, with the dual aim of expanding its nosographic value and considering the hemiplegic patient as worthy of the highest professional care La hemiplejia vascular, es el trastorno funcional de una mitad lateral del cuerpo producido por alteraciones de los vasos cerebrales. Conviene revisar los conceptos sobre esta frec...

  14. Valacyclovir in the treatment of acute retinal necrosis

    Directory of Open Access Journals (Sweden)

    Taylor Simon RJ

    2012-09-01

    Full Text Available Abstract Background To report the outcome of oral valacyclovir as the sole antiviral therapy for patients with acute retinal necrosis (ARN. Methods This study reports a retrospective, interventional case series of nine consecutive patients with ten eyes with newly diagnosed ARN treated with oral valacyclovir as the sole antiviral agent. Eight patients received oral valacyclovir 2 g tid (Valtrex, GlaxoSmithKline and one patient with impaired renal function received oral 1 g tid. The main outcome measures were response to treatment, time to initial response to treatment, time to complete resolution of retinitis, best corrected visual acuity (BCVA at final follow-up, retinal detachment and development of recurrent or second eye disease. Results Retinitis resolved in ten of ten (100% affected eyes. The median time to initial detectable response was seven days and the median time to complete resolution was 21 days. A final BCVA of 20/40 or better was achieved in 6/10 (60% of eyes. 3/10 eyes (30% developed a retinal detachment. No patients developed either disease reactivation or second eye involvement over the course of the study (mean follow up 31 weeks, range 7 to 104 weeks. Conclusions Treatment with oral valacyclovir as the sole antiviral therapy resulted in complete resolution of retinitis. Final BCVA and retinal detachment rate were comparable with previously reported outcomes for intravenous acyclovir.

  15. Unsupervised Retinal Vessel Segmentation Using Combined Filters.

    Science.gov (United States)

    Oliveira, Wendeson S; Teixeira, Joyce Vitor; Ren, Tsang Ing; Cavalcanti, George D C; Sijbers, Jan

    2016-01-01

    Image segmentation of retinal blood vessels is a process that can help to predict and diagnose cardiovascular related diseases, such as hypertension and diabetes, which are known to affect the retinal blood vessels' appearance. This work proposes an unsupervised method for the segmentation of retinal vessels images using a combined matched filter, Frangi's filter and Gabor Wavelet filter to enhance the images. The combination of these three filters in order to improve the segmentation is the main motivation of this work. We investigate two approaches to perform the filter combination: weighted mean and median ranking. Segmentation methods are tested after the vessel enhancement. Enhanced images with median ranking are segmented using a simple threshold criterion. Two segmentation procedures are applied when considering enhanced retinal images using the weighted mean approach. The first method is based on deformable models and the second uses fuzzy C-means for the image segmentation. The procedure is evaluated using two public image databases, Drive and Stare. The experimental results demonstrate that the proposed methods perform well for vessel segmentation in comparison with state-of-the-art methods.

  16. Unsupervised Retinal Vessel Segmentation Using Combined Filters.

    Directory of Open Access Journals (Sweden)

    Wendeson S Oliveira

    Full Text Available Image segmentation of retinal blood vessels is a process that can help to predict and diagnose cardiovascular related diseases, such as hypertension and diabetes, which are known to affect the retinal blood vessels' appearance. This work proposes an unsupervised method for the segmentation of retinal vessels images using a combined matched filter, Frangi's filter and Gabor Wavelet filter to enhance the images. The combination of these three filters in order to improve the segmentation is the main motivation of this work. We investigate two approaches to perform the filter combination: weighted mean and median ranking. Segmentation methods are tested after the vessel enhancement. Enhanced images with median ranking are segmented using a simple threshold criterion. Two segmentation procedures are applied when considering enhanced retinal images using the weighted mean approach. The first method is based on deformable models and the second uses fuzzy C-means for the image segmentation. The procedure is evaluated using two public image databases, Drive and Stare. The experimental results demonstrate that the proposed methods perform well for vessel segmentation in comparison with state-of-the-art methods.

  17. Multimodal Imaging in Hereditary Retinal Diseases

    Directory of Open Access Journals (Sweden)

    Francesco Pichi

    2013-01-01

    Full Text Available Introduction. In this retrospective study we evaluated the multimodal visualization of retinal genetic diseases to better understand their natural course. Material and Methods. We reviewed the charts of 70 consecutive patients with different genetic retinal pathologies who had previously undergone multimodal imaging analyses. Genomic DNA was extracted from peripheral blood and genotyped at the known locus for the different diseases. Results. The medical records of 3 families of a 4-generation pedigree affected by North Carolina macular dystrophy were reviewed. A total of 8 patients with Stargardt disease were evaluated for their two main defining clinical characteristics, yellow subretinal flecks and central atrophy. Nine male patients with a previous diagnosis of choroideremia and eleven female carriers were evaluated. Fourteen patients with Best vitelliform macular dystrophy and 6 family members with autosomal recessive bestrophinopathy were included. Seven patients with enhanced s-cone syndrome were ascertained. Lastly, we included 3 unrelated patients with fundus albipunctatus. Conclusions. In hereditary retinal diseases, clinical examination is often not sufficient for evaluating the patient’s condition. Retinal imaging then becomes important in making the diagnosis, in monitoring the progression of disease, and as a surrogate outcome measure of the efficacy of an intervention.

  18. Prevalence of outer retinal tubulation in eyes with choroidal neovascularization

    OpenAIRE

    Giachetti Filho, Richard Geraldo; Zacharias,Leandro Cabral; Monteiro,Thaís Vera; Preti, Rony Carlos; Pimentel, Sérgio Gianoti

    2016-01-01

    Background Outer retinal tubulations (ORTs) are branching tubular structures located in the outer nuclear layer of the retina. The goal of this study is to determine the prevalence of ORTs observed in eyes with choroidal neovascularization (CNV) undergoing treatment with anti-angiogenic intravitreous injection (IVI) with anti-VEGF (vascular endothelial growth factor) at the Ophthalmology Department of a tertiary hospital in São Paulo, Brazil. Methods This is a descriptive study based on medic...

  19. Duration of rhegmatogenous retinal detachment predicts recovery of retinal sensitivity

    Directory of Open Access Journals (Sweden)

    Rose Rose

    2016-02-01

    Full Text Available The decision to treat a disease is often based on the presence or absence of symptoms, one prototype case being rhegmatogenous retinal detachment. Detachment of the neural retina from the pigment epithelium is a major cause of anatomical and functional dysfunction of the retina, where retinal recovery is inversely related to duration of detachment. The purpose of retinal reattachment is to effect recovery of the photoreceptors and pigment epithelium from degeneration. The aim of this study was to determine the critical duration of rhegmatogenous retinal detachment resulting in optimal retinal recovery after reattachment. A prospective study was conducted at a private hospital in Yogyakarta. Thirty five eyes were involved in this study. Three months after reattachment, central retinal recovery was measured by means of a Goldmann manual kinetic perimeter. The results showed that retinal recovery developed three months after surgery if the onset of rhegmatogenous retinal detachment was less than 28 days before surgery. The results were not significant if the onset of rhegmatogenous retinal detachment was more than 35 days. Although the Goldmann manual kinetic perimeter can efficiently detect central retinal sensitivity, it should be supported by more sensitive tools to evaluate the anatomy and function of the retina.

  20. Neuroprotective Effects of Citicoline in in Vitro Models of Retinal Neurodegeneration

    OpenAIRE

    Andrea Matteucci; Monica Varano; Lucia Gaddini; Cinzia Mallozzi; Marika Villa; Flavia Pricci; Fiorella Malchiodi-Albedi

    2014-01-01

    In recent years, citicoline has been the object of remarkable interest as a possible neuroprotectant. The aim of this study was to investigate if citicoline affected cell survival in primary retinal cultures and if it exerted neuroprotective activity in conditions modeling retinal neurodegeneration. Primary retinal cultures, obtained from rat embryos, were first treated with increasing concentrations of citicoline (up to 1000 µM) and analyzed in terms of apoptosis and caspase activation and c...

  1. Peripapillary retinal thermal coagulation following electrical injury

    Directory of Open Access Journals (Sweden)

    Manjari Tandon

    2013-01-01

    Full Text Available In this study, we have presented the case report of a 20 year old boy who suffered an electric injury shock, following which he showed peripapillary retinal opacification and increased retinal thickening that subsequently progressed to retinal atrophy. The fluorescein angiogram revealed normal retinal circulation, thus indicating thermal damage to retina without any compromise to retinal circulation.

  2. NADPH Oxidase 4-Derived H2O2 Promotes Aberrant Retinal Neovascularization via Activation of VEGF Receptor 2 Pathway in Oxygen-Induced Retinopathy

    Directory of Open Access Journals (Sweden)

    Jingming Li

    2015-01-01

    Full Text Available NADPH oxidase 4 (Nox4 is a major isoform of NADPH oxidase in retinal endothelial cells. Our previous study suggests that upregulation of Nox4 in retinal endothelial cells contributes to retinal vascular leakage in diabetes. In the current study, we investigated the role and mechanism of Nox4 in regulation of retinal neovascularization (NV, a hallmark of proliferative diabetic retinopathy (PDR, using a mouse model of oxygen-induced retinopathy (OIR. Our results confirmed that Nox4 was expressed predominantly in retinal vasculature of mouse retina. Retinal expression of Nox4 was markedly increased in OIR, in parallel with enhanced phosphorylation of ERK. In human retinal microvascular endothelial cells (HRECs, overexpression of Nox4 by adenovirus significantly increased extracellular H2O2 generation, resulting in intensified VEGFR2 activation and exacerbated angiogenesis upon VEGF stimulation. In contrast, silencing Nox4 expression or scavenging H2O2 by polyethylene glycol- (PEG- conjugated catalase inhibited endothelial migration, tube formation, and VEGF-induced activation of VEGFR2 signaling. Importantly, knockdown of retinal Nox4 by adenovirus-delivered siRNA significantly reduced ERK activation and attenuated retinal NV formation in OIR. Taken together, our data indicate that Nox4 promotes retinal NV formation through H2O2/VEGFR2/ERK signaling pathway. Reducing retinal Nox4 expression may represent a promising therapeutic approach for neovascular retinal diseases such as PDR.

  3. A content analysis of cognitive and affective uses of patient support groups for rare and uncommon vascular diseases: comparisons of may thurner, thoracic outlet, and superior mesenteric artery syndrome.

    Science.gov (United States)

    Walker, Kimberly K

    2015-01-01

    Rare disease patients are the predominant group of patients who are now connecting online to patient support groups, yet research on their uses of support groups has received little attention. This is a content analysis of three vascular diseases of differing degrees of rarity. Wall posts from Facebook patient support groups for May Thurner syndrome, thoracic outlet syndrome, and superior mesenteric artery syndrome were analyzed over a period of two years. Using Uses and Gratifications as the theoretical framework, the study purpose was to assess how variations in health condition and rarity of condition affect online support group user needs. Results indicated common main cognitive and affective uses across conditions, indicating a consistent pattern of needs communicated by all patients. However, there were nuanced differences in subcategories of cognitive and affective uses between the most and least rare disorders, which inform areas for tailored support mechanisms. Additionally, these vascular patients used their respective support groups primarily for cognitive reasons, especially for the rarest conditions, which informs of basic medical informational needs these patients face related to tests, treatment, surgery, and diagnoses.

  4. AMP-Activated Protein Kinase α2 in Neutrophils Regulates Vascular Repair via Hypoxia-Inducible Factor-1α and a Network of Proteins Affecting Metabolism and Apoptosis

    Science.gov (United States)

    Abdel Malik, Randa; Zippel, Nina; Frömel, Timo; Heidler, Juliana; Zukunft, Sven; Walzog, Barbara; Ansari, Nariman; Pampaloni, Francesco; Wingert, Susanne; Rieger, Michael A.; Wittig, Ilka; Fisslthaler, Beate

    2017-01-01

    Rationale: The AMP-activated protein kinase (AMPK) is stimulated by hypoxia, and although the AMPKα1 catalytic subunit has been implicated in angiogenesis, little is known about the role played by the AMPKα2 subunit in vascular repair. Objective: To determine the role of the AMPKα2 subunit in vascular repair. Methods and Results: Recovery of blood flow after femoral artery ligation was impaired (>80%) in AMPKα2−/− versus wild-type mice, a phenotype reproduced in mice lacking AMPKα2 in myeloid cells (AMPKα2ΔMC). Three days after ligation, neutrophil infiltration into ischemic limbs of AMPKα2ΔMC mice was lower than that in wild-type mice despite being higher after 24 hours. Neutrophil survival in ischemic tissue is required to attract monocytes that contribute to the angiogenic response. Indeed, apoptosis was increased in hypoxic neutrophils from AMPKα2ΔMC mice, fewer monocytes were recruited, and gene array analysis revealed attenuated expression of proangiogenic proteins in ischemic AMPKα2ΔMC hindlimbs. Many angiogenic growth factors are regulated by hypoxia-inducible factor, and hypoxia-inducible factor-1α induction was attenuated in AMPKα2-deficient cells and accompanied by its enhanced hydroxylation. Also, fewer proteins were regulated by hypoxia in neutrophils from AMPKα2ΔMC mice. Mechanistically, isocitrate dehydrogenase expression and the production of α-ketoglutarate, which negatively regulate hypoxia-inducible factor-1α stability, were attenuated in neutrophils from wild-type mice but remained elevated in cells from AMPKα2ΔMC mice. Conclusions: AMPKα2 regulates α-ketoglutarate generation, hypoxia-inducible factor-1α stability, and neutrophil survival, which in turn determine further myeloid cell recruitment and repair potential. The activation of AMPKα2 in neutrophils is a decisive event in the initiation of vascular repair after ischemia. PMID:27777247

  5. Bietti crystalline retinal dystrophy with subfoveal neurosensory detachment and congenital tortuosity of retinal vessels: case report.

    Science.gov (United States)

    Padhi, Tapas Ranjan; Kesarwani, Siddharth; Jalali, Subhadra

    2011-06-01

    A 34-year-old man presented with reduction and distortion of vision in both the eyes. The best-corrected vision was 20/20 parts, N6 in either eye. The external and slit lamp examination of both the eyes was unremarkable. The fundus examination showed multiple intraretinal crystalline deposits at the posterior pole, extending up to midperiphery, tortuous retinal blood vessels with S-shaped deflections, and absent foveal reflex in both the eyes. There were no corneal crystals, and the color vision was defective in both the eyes. Fundus autofluorescence and fundus fluorescein angiogram (FFA) were suggestive of geographic areas of retinal pigment epithelium (RPE) and choriocapillary (CC) loss. OCT revealed subfoveal neurosensory detachment. Flash ERG and EOG were normal except for a slight decrease in amplitude and delay in latency of pattern ERG waveforms. The Humphrey's visual field showed paracentral scotoma with reduction in the amplitude of waveforms from the corresponding area in the multifocal ERG in both the eyes. Systemic evaluation for crystalline retinopathy was unremarkable. He was diagnosed to be a case of Bietti crystalline retinopathy (local/regional variant). The subfoveal neurosensory detachment could represent early RPE dysfunction caused by these crystals and could account for the mild visual disturbance in both the eyes. Retinal vascular tortuosity and neurosensory detachment seen in this case is the first time to be reported in literature.

  6. The Extract of Aster Koraiensis Prevents Retinal Pericyte Apoptosis in Diabetic Rats and Its Active Compound, Chlorogenic Acid Inhibits AGE Formation and AGE/RAGE Interaction

    Directory of Open Access Journals (Sweden)

    Junghyun Kim

    2016-09-01

    Full Text Available Retinal capillary cell loss is a hallmark of early diabetic retinal changes. Advanced glycation end products (AGEs are believed to contribute to retinal microvascular cell loss in diabetic retinopathy. In this study, the protective effects of Aster koraiensis extract (AKE against damage to retinal vascular cells were investigated in streptozotocin (STZ-induced diabetic rats. To examine this issue further, AGE accumulation, nuclear factor-kappaB (NF-κB and inducible nitric oxide synthase (iNOS were investigated using retinal trypsin digests from streptozotocin-induced diabetic rats. In the diabetic rats, TUNEL (Terminal deoxynucleotidyl transferase mediated dUTP Nick End Labeling-positive retinal microvascular cells were markedly increased. Immunohistochemical studies revealed that AGEs were accumulated within the retinal microvascular cells, and this accumulation paralleled the activation of NF-κB and the expression of iNOS in the diabetic rats. However, AKE prevented retinal microvascular cell apoptosis through the inhibition of AGE accumulation and NF-κB activation. Moreover, to determine the active compounds of AKE, two major compounds, chlorogenic acid and 3,5-di-O-caffeoylquinic acid, were tested in an in vitro assay. Among these compounds, chlorogenic acid significantly reduced AGE formation as well as AGE/RAGE (receptor for AGEs binding activity. These results suggest that AKE, particularly chlorogenic acid, is useful in inhibiting AGE accumulation in retinal vessels and exerts a preventive effect against the injuries of diabetic retinal vascular cells.

  7. Specific inhibition of TRPV4 enhances retinal ganglion cell survival in adult porcine retinal explants.

    Science.gov (United States)

    Taylor, Linnéa; Arnér, Karin; Ghosh, Fredrik

    2017-01-01

    Signaling through the polymodal cation channel Transient Receptor Potential Vanilloid 4 (TRPV4) has been implicated in retinal neuronal degeneration. To further outline the involvement of this channel in this process, we here explore modulation of Transient Receptor Potential Vanilloid 4 (TRPV4) activity on neuronal health and glial activation in an in vitro model of retinal degeneration. For this purpose, adult porcine retinal explants were cultured using a previously established standard protocol for up to 5 days with specific TRPV4 agonist GSK1016790A (GSK), or specific antagonist RN-1734, or culture medium only. Glial and neuronal cell health were evaluated by a battery of immunohistochemical markers, as well as morphological staining. Specific inhibition of TRPV4 by RN-1734 significantly enhanced ganglion cell survival, improved the maintenance of the retinal laminar architecture, reduced apoptotic cell death and attenuated the gliotic response as well as preserved the expression of TRPV4 in the plexiform layers and ganglion cells. In contrast, culture controls, as well as specimens treated with GSK, displayed rapid remodeling and neurodegeneration as well as a downregulation of TRPV4 and the Müller cell homeostatic mediator glutamine synthetase. Our results indicate that TRPV4 signaling is an important contributor to the retinal degeneration in this model, affecting neuronal cell health and glial homeostasis. The finding that pharmacological inhibition of the receptor significantly attenuates neuronal degeneration and gliosis in vitro, suggests that TRPV4 signaling may be an interesting pharmaceutical target to explore for treatment of retinal degenerative disease.

  8. Retinal flow cytometer

    OpenAIRE

    Alt, C.; Veilleux, I.; H. Lee; Pitsillides, C. M.; Côté, D.; Lin, C.P.

    2007-01-01

    The in vivo flow cytometer is an instrument capable of continuous, real-time monitoring of fluorescently labeled cells in the circulation without the need to draw blood samples. However, the original system probes a single vessel in the mouse ear; the small sample volume limits the sensitivity of the technique. We describe an in vivo retinal flow cytometer that simultaneously probes five artery–vein pairs in the mouse eye by circularly scanning a small laser spot rapidly around the optic nerv...

  9. Inherited Retinal Degenerative Disease Registry

    Science.gov (United States)

    2016-03-21

    Eye Diseases Hereditary; Retinal Disease; Achromatopsia; Bardet-Biedl Syndrome; Bassen-Kornzweig Syndrome; Batten Disease; Best Disease; Choroidal Dystrophy; Choroideremia; Cone Dystrophy; Cone-Rod Dystrophy; Congenital Stationary Night Blindness; Enhanced S-Cone Syndrome; Fundus Albipunctatus; Goldmann-Favre Syndrome; Gyrate Atrophy; Juvenile Macular Degeneration; Kearns-Sayre Syndrome; Leber Congenital Amaurosis; Refsum Syndrome; Retinitis Pigmentosa; Retinitis Punctata Albescens; Retinoschisis; Rod-Cone Dystrophy; Rod Dystrophy; Rod Monochromacy; Stargardt Disease; Usher Syndrome

  10. Vascular Remodeling in Experimental Hypertension

    Directory of Open Access Journals (Sweden)

    Norma R. Risler

    2005-01-01

    Full Text Available The basic hemodynamic abnormality in hypertension is an increased peripheral resistance that is due mainly to a decreased vascular lumen derived from structural changes in the small arteries wall, named (as a whole vascular remodeling. The vascular wall is an active, flexible, and integrated organ made up of cellular (endothelial cells, smooth muscle cells, adventitia cells, and fibroblasts and noncellular (extracellular matrix components, which in a dynamic way change shape or number, or reorganize in response to physiological and pathological stimuli, maintaining the integrity of the vessel wall in physiological conditions or participating in the vascular changes in cardiovascular diseases such as hypertension. Research focused on new signaling pathways and molecules that can participate in the mechanisms of vascular remodeling has provided evidence showing that vascular structure is not only affected by blood pressure, but also by mechanisms that are independent of the increased pressure. This review will provide an overview of the evidence, explaining some of the pathophysiologic mechanisms participating in the development of the vascular remodeling, in experimental models of hypertension, with special reference to the findings in spontaneously hypertensive rats as a model of essential hypertension, and in fructose-fed rats as a model of secondary hypertension, in the context of the metabolic syndrome. The understanding of the mechanisms producing the vascular alterations will allow the development of novel pharmacological tools for vascular protection in hypertensive disease.

  11. Retinal Thickening and Photoreceptor Loss in HIV Eyes without Retinitis.

    Directory of Open Access Journals (Sweden)

    Cheryl A Arcinue

    Full Text Available To determine the presence of structural changes in HIV retinae (i.e., photoreceptor density and retinal thickness in the macula compared with age-matched HIV-negative controls.Cohort of patients with known HIV under CART (combination Antiretroviral Therapy treatment were examined with a flood-illuminated retinal AO camera to assess the cone photoreceptor mosaic and spectral-domain optical coherence tomography (SD-OCT to assess retinal layers and retinal thickness.Twenty-four eyes of 12 patients (n = 6 HIV-positive and 6 HIV-negative were imaged with the adaptive optics camera. In each of the regions of interest studied (nasal, temporal, superior, inferior, the HIV group had significantly less mean cone photoreceptor density compared with age-matched controls (difference range, 4,308-6,872 cones/mm2. A different subset of forty eyes of 20 patients (n = 10 HIV-positive and 10 HIV-negative was included in the retinal thickness measurements and retinal layer segmentation with the SD-OCT. We observed significant thickening in HIV positive eyes in the total retinal thickness at the foveal center, and in each of the three horizontal B-scans (through the macular center, superior, and inferior to the fovea. We also noted that the inner retina (combined thickness from ILM through RNFL to GCL layer was also significantly thickened in all the different locations scanned compared with HIV-negative controls.Our present study shows that the cone photoreceptor density is significantly reduced in HIV retinae compared with age-matched controls. HIV retinae also have increased macular retinal thickness that may be caused by inner retinal edema secondary to retinovascular disease in HIV. The interaction of photoreceptors with the aging RPE, as well as possible low-grade ocular inflammation causing diffuse inner retinal edema, may be the key to the progressive vision changes in HIV-positive patients without overt retinitis.

  12. Vascular Disease Foundation

    Science.gov (United States)

    ... Contact Us Vascular Disease What is Vascular Disease? Education and Awareness Vascular Diseases Abdominal Aortic Aneurysm Aortic Dissection Arteriovenous Malformation Atherosclerosis Buerger's Disease Carotid Artery Disease ...

  13. What Is Vascular Disease?

    Science.gov (United States)

    ... Contact Us Vascular Disease What is Vascular Disease? Education and Awareness Vascular Diseases Abdominal Aortic Aneurysm Aortic Dissection Arteriovenous Malformation Atherosclerosis Buerger's Disease Carotid Artery Disease ...

  14. Vascular emergencies.

    Science.gov (United States)

    Semashko, D C

    1997-01-01

    This article reviews the initial assessment and emergent management of several common as well as uncommon vascular emergencies. Aortic dissection, aneurysms, and arterial occlusive disease are familiar but challenging clinical entities. Less frequently encountered conditions are also discussed including an aortic enteric fistula, mesenteric venous thrombosis, phlegmasia alba dolens, and subclavian vein thrombosis.

  15. [Application of retinal oximeter in ophthalmology].

    Science.gov (United States)

    Li, Jing; Ma, Jianmin; Wang, Ningli

    2015-11-01

    Retinal oximeter is a new machine which has been used in the diagnose, treatment and research of several ophthalmic diseases for recent years. It allows ophthalmologists to gain retinal oxygen saturation directly. Therefore, retinal oximeter might be useful for ophthalmologists to understand ophthalmic diseases more deeper and clarify the impact of ischemia on retinal function. It has been reported in the literatures that retinal oximeter has potentially useful diagnostic and therapeutic indications in various eye diseases such as diabetic retinopathy, central retinal vein and artery occlusion, retinitis pigmentosa, glaucomatous optic neuropathy, et al. In this thesis, the application of retinal oximeter in ophthalmology is reviewed.

  16. Observation and management of retinal changes related to diving in professional divers

    Institute of Scientific and Technical Information of China (English)

    Zhou Dan; Wei Wenbin; Tian Bei; Wang Cong; Shi Xuehui; Jiao Xuan

    2014-01-01

    Background It is very common for professional divers to have damage on the retinas.Severe retinal lesions can profoundly affect athletes' training efficacy and their daily lives.At present,it is not clear if there is effective preventive action.Thus,in our study,we continuously tracked the ocular changes in athletes and closely monitored the risk factors associated with retinal detachment.Also,we analyzed possible interventions,their associated factors,and efficacies for timely preventions to protect the retina from damage in professional divers.Methods Between 2009 and 2012,a total of 39 professional divers enrolled in follow-up management.The conducted examinations included ocular examination,record screening on retinal lesion,monitoring best-corrected visual acuity,and checking intraocular pressure (lOP) and the scope of retinal lesion.The management included optimizing training methods,taking customized follow-up based on different retinal lesions,laser treatments for definite cases of retinal tear,retinal degeneration caused by retinal layer thinning or vitreous traction,and observing the changes in the scope of retinopathy.Results Every year,the percentage of divers who have various degrees of retinal lesions is between 43.3% and 56.2%.During the 4 years,there were no statistically significant differences in divers' best-corrected visual acuity and retinal lesions.There were also no statistically significant differences between male and female athletes.However,there were statistically significant differences in lOP during these years.Moreover there were statistically significant differences in IOP and the scope of retinal lesions between platform divers and springboard divers.Conclusions Our management of retinal lesions could be effective to prevent severe retinopathy in professional divers.At the same time,platform divers are more likely to have retinal lesions than springboard divers.

  17. Loss of caveolin-1 causes blood-retinal barrier breakdown, venous enlargement, and mural cell alteration.

    Science.gov (United States)

    Gu, Xiaowu; Fliesler, Steven J; Zhao, You-Yang; Stallcup, William B; Cohen, Alex W; Elliott, Michael H

    2014-02-01

    Blood-retinal barrier (BRB) breakdown and related vascular changes are implicated in several ocular diseases. The molecules and mechanisms regulating BRB integrity and pathophysiology are not fully elucidated. Caveolin-1 (Cav-1) ablation results in loss of caveolae and microvascular pathologies, but the role of Cav-1 in the retina is largely unknown. We examined BRB integrity and vasculature in Cav-1 knockout mice and found a significant increase in BRB permeability, compared with wild-type controls, with branch veins being frequent sites of breakdown. Vascular hyperpermeability occurred without apparent alteration in junctional proteins. Such hyperpermeability was not rescued by inhibiting eNOS activity. Veins of Cav-1 knockout retinas exhibited additional pathological features, including i) eNOS-independent enlargement, ii) altered expression of mural cell markers (eg, down-regulation of NG2 and up-regulation of αSMA), and iii) dramatic alterations in mural cell phenotype near the optic nerve head. We observed a significant NO-dependent increase in retinal artery diameter in Cav-1 knockout mice, suggesting that Cav-1 plays a role in autoregulation of resistance vessels in the retina. These findings implicate Cav-1 in maintaining BRB integrity in retinal vasculature and suggest a previously undefined role in the retinal venous system and associated mural cells. Our results are relevant to clinically significant retinal disorders with vascular pathologies, including diabetic retinopathy, uveoretinitis, and primary open-angle glaucoma.

  18. Gestational diabetes, pregnancy hypertension, and late vascular disease.

    Science.gov (United States)

    Carpenter, Marshall W

    2007-07-01

    The complexity of the several pathogenic pathways that cause hypertension and vascular disease and the prolonged interval that appears to predate clinical morbidity have hindered inquiry into the association between GDM and vascular disorders. As a forme fruste of later type 2 diabetes, GDM-affected gravidas are identified as at risk of diabetes-related atherosclerosis, glomerular disruption, and pathogenic retinal angio-genesis. That GDM is evidence for underlying chronic conditions such as dysregulation of innate immune response that, independent of the diabetic state, produces vascular disease is difficult state, produces vascular disease is difficult to assert with the present published literature. Cross-sectional studies of patients with established gestational hypertension or preeclampsia are ambiguous as to the possible pathogenic effect of insulin resistance. Cohort studies initiated in early and mid-pregnancy show evidence that both gestational hypertension and preeclampsia may be more prevalent in gravidas with greater insulin resistance. The association of gestational glucose intolerance with gestational hypertension appears to be independent of obesity and ambient glycemia but explained in part by insulin resistance. Late pregnancy preeclampsia is associated with elevated mid-pregnancy BMI, blood pressure, fasting glucose and insulin, urate, and C-reactive protein, suggestive of metabolic and immune dysregulation. GDM appears to be associated with overexpressed innate immune response, which, in turn, is associated with vascular dysfunction and vascular disease. Among women with GDM, markers of insulin resistance do not appear to correlate with hypertension in short-term cohort studies. However, when non-GDM subjects are compared with subjects with GDM, postpregnancy studies do show an associated with vascular dysfunction and vascular disease. Among women with GDM, markers of insulin resistance do not appear to correlate with hypertension in short

  19. Thrombophilic screening in retinal artery occlusion patients

    Directory of Open Access Journals (Sweden)

    Valeria Nagy

    2008-10-01

    Full Text Available Valeria Nagy1, Lili Takacs1, Zita Steiber1, György Pfliegler2, Andras Berta11Department of Ophthalmology, 2Division of Rare Diseases, University of Debrecen Medical and Health Science Center, Debrecen, HungaryBackground: Retinal artery occlusion (RAO is an ischemic vascular damage of the retina, which frequently leads to sudden, mostly irreversible loss of vision. In this study, blood thrombophilic factors as well as cardiovascular risk factors were investigated for their relevance to this pathology. Thrombophilic risk factors so far not evaluated were included in the study.Patients and methods: 28 RAO patients and 81 matched control subjects were examined. From blood samples, protein C, protein S, antithrombinopathy, and factor V (Leiden mutation (FV, factor II gene polymorphism, factor VIII C level, plasminogen activity, lipoprotein(a and fibrinogen levels, hyperhomocysteinemia and presence of anticardiolipin – antiphospholipid antibodies were investigated. Possibly relevant pathologies such as diabetes mellitus, hypertension, and ischemic heart disease were also registered. Statistical analysis by logistic regression was performed with 95% confidence intervals.Results: In the group of patients with RAO only the incidence of hypertension (OR: 3.33, 95% CI: 1.30–9.70, p = 0.014 as an average risk factor showed significant difference, but thrombophilic factors such as hyperfibrinogenemia (OR: 2.9, 95% CI: 1.29–6.57, p = 0.010 and the presence of FV (Leiden mutation (OR: 3.9, 95% CI: 1.43–10.96, p = 0.008 increased the chances of developing this disease.Conclusions: Our results support the assumption that thrombophilia may contribute to the development of RAO besides vascular damage due to the presence of cardiovascular risk factors. Further studies are needed, however, to justify the possible use of secondary prophylaxis in form of anticoagulant/antiplatelet therapy.Keywords: retinal arterial occlusion, risk factors, thrombophilia

  20. Perceptual Fading without Retinal Adaptation

    Science.gov (United States)

    Hsieh, Po-Jang; Colas, Jaron T.

    2012-01-01

    A retinally stabilized object readily undergoes perceptual fading and disappears from consciousness. This startling phenomenon is commonly believed to arise from local bottom-up sensory adaptation to edge information that occurs early in the visual pathway, such as in the lateral geniculate nucleus of the thalamus or retinal ganglion cells. Here…

  1. Retinal detachment surgery without cryotherapy.

    OpenAIRE

    Chignell, A H; Markham, R H

    1981-01-01

    A series of cases of retinal detachment treated without the application of cryotherapy at the time of surgery has been studied. The omission of cryotherapy while not interfering with retinal reattachment, carries the risk of redetachment at a later date. Macular pucker may still occur in spite of the absence of cryotherapy.

  2. Acute and chronic spectral domain optical coherence tomography features of branch retinal artery occlusion

    Science.gov (United States)

    Rodrigues, Ian Aureliano Stephen

    2013-01-01

    Branch retinal artery occlusion (BRAO) is a common vascular occlusive disorder. BRAO involving the posterior pole is usually symptomatic, but occasionally has very limited clinical features. We describe 2 cases where the underlying pathology was initially unclear and the diagnosis therefore not reached at presentation. Use of the latest retinal imaging, spectral domain optical coherence tomography (SD-OCT) enabled correct diagnosis of BRAO. The images demonstrate and contrast the fine changes that can be seen in the acute and chronic phases of this condition and illustrate how the pathogenesis of BRAO is confined to the outer retinal layers. We believe the subtle presentations of this common condition that we discuss highlight how diagnosis of BRAO can often be challenging, but may be facilitated by the use of SD-OCT retinal imaging. PMID:23661655

  3. Retinal Vessel Caliber and Lifelong Neuropsychological Functioning: An Investigative Tool for Cognitive Epidemiology

    Science.gov (United States)

    Shalev, Idan; Moffitt, Terrie E.; Wong, Tien Y.; Meier, Madeline H.; Houts, Renate M.; Ding, Jie; Cheung, Carol YL; Ikram, M. Kamram; Caspi, Avshalom; Poulton, Richie

    2013-01-01

    Why do more intelligent people live healthier and longer lives? One possibility is that intelligence tests assess health of the brain, but psychological science has lacked technology to evaluate this hypothesis. Digital retinal imaging, a new non-invasive method to visualize microcirculation in the eye, may reflect vascular conditions in the brain. We studied the association between retinal vessel caliber and neuropsychological functioning in the representative Dunedin birth cohort. Wider venular caliber was associated with poorer neuropsychological functioning at midlife, independent of potentially confounding factors. This association was not limited to any specific test domain, and extended to informant-reports of cognitive difficulties in everyday life. Moreover, wider venular caliber was associated with lower childhood IQ tested 25 years earlier. The finding indicates that retinal venular caliber may be an indicator of neuropsychological health years before dementing diseases’ onset, and suggests digital retinal imaging as an investigative tool for psychological science. PMID:23678508

  4. [Retinal and trabecular degeneration in glaucoma: new insights into pathogenesis and treatment].

    Science.gov (United States)

    Denoyer, A; Roubeix, C; Sapienza, A; Réaux-Le Goazigo, A; Mélik-Parsadaniantz, S; Baudouin, C

    2015-04-01

    Academic and industrial research has brought new insights into the pathogenesis of glaucoma, aiming at identifying and targeting specific mechanisms to improve our current therapeutic strategy. Retinal neurodegeneration is still the main focus, whether in terms of extrinsic factors such as neurotrophin deprivation, glutamate toxicity, vascular deficiency and neuro-inflammation from glial cells, or in terms of retinal ganglion cell intrinsic sensibility to proapoptotic signals. However, glaucoma is not solely a retinal disease but also involves retinal and trabecular meshwork degeneration, extending into and/or even originating from the brain. The present review summarizes our current knowledge of key mechanisms involved in glaucoma degeneration, focusing on the direction of current research towards the future of glaucoma therapy.

  5. One day wonder: Fast resolution of macular edema following intravitreal ranibizumab in retinal venous occlusions

    Directory of Open Access Journals (Sweden)

    Lalit Verma

    2013-01-01

    Full Text Available Macular edema is a significant cause of vision loss in patients with central retinal vein occlusions and branch retinal vein occlusions. Vascular endothelial growth factor (VEGF appears to be a key factor in the pathogenesis of this disease. Anti-VEGF therapy, such as intravitreal ranibizumab provides an effective treatment against vision-threatening macular edema. We report three patients of retinal vein occlusion with macular edema who demonstrated overnight resolution of macular edema following treatment with intravitreal ranibizumab (0.5 mg. 3D optical coherence tomography (Optovue was used as a tool for comparison of the macular thickness before and after treatment. The significant reductions in the central foveal thickness demonstrated in these patients one night after intravitreal injections could have significant influence on modifying current treatment protocols. Early treatment of macular edema related to retinal venous occlusive disease with anti-VEGF injections could result in faster visual rehabilitation in these patients.

  6. Identifying All True Vessels from Segmented Retinal Images

    Directory of Open Access Journals (Sweden)

    G. Delucta Mary

    2014-02-01

    Full Text Available Measurements of retinal blood vessel morphology have been shown to be related to the risk of cardiovascular diseases. The wrong identification of vessels may result in a large variation of these measurements, leading to a wrong clinical diagnosis Both the arteries and veins of the retina are generally binary trees, whose properties can be considered either locally or globally. Measurable geometrical changes in diameter, branching angle, length, or tortuosity, as a result of disease, have been described in retinal blood vessels. The detection and measurement of retinal blood vessels can be used to quantify the severity of disease such as hypertension, stroke and arteriosclerosis, as part of the process of automated diagnosis of disease or in the assessment of the progression of therapy. Thus, a reliable method of vessel detection and quantification would be valuable. In this paper, we address the problem of identifying true vessels as a postprocessing step to vascular structure segmentation. We model the segmented vascular structure as a vessel segment graph and formulate the problem of identifying vessels as one of finding the optimal forest in the graph given a set of constraints.

  7. Effectiveness of combined laser photocoagulation therapy with intravitreal anti -VEGF in Retinal arterial macroaneurysms: case report

    Directory of Open Access Journals (Sweden)

    Fernanda Pacella

    2014-12-01

    Full Text Available Background: Retinal arterial macroaneurysms (RAM is a pathological dilatation of retinal arterial vessel. Argon laser photocoagulation has been for a long time the gold standard of many vascular diseases of the retina such as macroaneurysm. From this work emerges how the introduction of intravitreal anti-VEGF therapies have enhanced the 'effectiveness of the combination of argon laser photocoagulation in cases of persistent retinal edema, we present the case of a retinal macroaneurysm with macular hemorrhage focus and oedema in a patient with a history of systemic arterial hypertension. Methods: A 77 year-old woman patient reported sudden decline in visual acuity in the left eye; the best corrected visual acuity (BCVAwas 1/10 in left eye. Fluorescein angiography (FAG resulted in diagnosis of Macroaneurysm at the posterior pole with macular hemorrhage focus and oedema. The patient was treated with laser treatment in the left eye; after 30 days, the visual acuity was 1/50 and at optical coherence tomography (OCT the retinal profile was significantly altered. After 30 days, a single intravitreal ranibizumab injection was performed and, after 7 days, visual acuity was 1/10. After 24 months from ranibizumab-based therapy the final visual acuity was 10/10 and OCT examination revealed a normal retinal profile. Conclusion: In this case report the association of argon laser photocoagulation with intravitreal anti-VEGF injection has been proven to be effective and safe in case of persistent retinal oedema.

  8. The relationship between retinal vessel calibre and knee cartilage and BMLs

    Directory of Open Access Journals (Sweden)

    Davies-Tuck Miranda L

    2012-12-01

    Full Text Available Abstract Background Whether the increase in vascular disease prevalence and mortality in OA populations is a result of co-occurrence of cardiovascular disease and OA, which are both common in the older population, is due to OA treatments or to the common association with reduced physical activity and/or obesity is unclear. One way to explore this non-invasively is to examine the cross-sectional relationship between changes in retinal microvasculature, which have been shown to be markers of generalized vascular pathology, and knee structural changes in an asymptomatic community-based population. Methods A community sample of 289 (61% women aged 50–79 years with no knee symptoms underwent magnetic resonance imaging (MRI of their dominant knee in 2003. Cartilage volume and bone marrow lesions (BMLs were determined. All subjects also had retinal photographs taken from which retinal arteriolar and venular diameters were determined and summarized as the central retinal arteriolar equivalent (CRAE and the central retinal venular equivalent (CRVE. Results Retinal venular diameter was significantly wider in subjects with a BML compared with subjects without a BML (mean (SD 214.2 (2.8 μm versus 207.5 (1.1 μm respectively independent of age, gender and BMI. A trend for decreased medial tibial cartilage with increasing CRAE was also observed (regression coefficient −2.70 μl, 95%CI-5.74, 0.5, p=0.08. Conclusion These findings suggest that vascular pathology, indicative of inflammatory processes, is associated with early structural knee changes. The role of micro-vascular changes in the pathogenesis of OA warrants further investigation.

  9. Microvascular network topology of the human retinal vessels.

    Science.gov (United States)

    Schröder, S; Brab, M; Schmid-Schönbein, G W; Reim, M; Schmid-Schönbein, H

    1990-01-01

    A quantitative analysis of blood flow in the human retinal vessels requires a detailed picture of the microvascular network topology. In order to lay the foundation for a quantitative microcirculatory network analysis of the human retina, a novel technique for tissue preparation and network characterization was developed. After injection of hydrogen peroxide into the human bulb, the microvasculature was filled with oxygen produced by endothelial catalase and visualized after embedding in a mixture of cedar oil and gum damar. The vessel topology was documented in the form of photomicrographs, which permitted complete reconstruction of the microvasculature on transparent overlays. By considering the complete capillary system it was possible to divide the retinal network into dichotomous, asymmetric arteriolar and venular trees. The Strahler ordering method, which considers both dichotomous and side branching configurations, was selected and applied to analyze the retinal vascular trees, using the capillaries as the zero order reference vessels. The number of vessel segments was found to be an approximate logarithmic function of the order number, in accordance with Horton's law. Vessel lengths within each order were found to be log-normal distributed, and median lengths for different orders could be approximated by a 2nd degree polynomial curve. Diameters within each order could be approximated by a Gaussian distribution, and the mean values for different orders could be expressed by an exponential curve. These data provide the basis for conductance, pressure and flow computations within the retinal microvessels.

  10. The Ketogenic Diet Alters the Hypoxic Response and Affects Expression of Proteins Associated with Angiogenesis, Invasive Potential and Vascular Permeability in a Mouse Glioma Model.

    Directory of Open Access Journals (Sweden)

    Eric C Woolf

    Full Text Available The successful treatment of malignant gliomas remains a challenge despite the current standard of care, which consists of surgery, radiation and temozolomide. Advances in the survival of brain cancer patients require the design of new therapeutic approaches that take advantage of common phenotypes such as the altered metabolism found in cancer cells. It has therefore been postulated that the high-fat, low-carbohydrate, adequate protein ketogenic diet (KD may be useful in the treatment of brain tumors. We have demonstrated that the KD enhances survival and potentiates standard therapy in a mouse model of malignant glioma, yet the mechanisms are not fully understood.To explore the effects of the KD on various aspects of tumor growth and progression, we used the immunocompetent, syngeneic GL261-Luc2 mouse model of malignant glioma.Tumors from animals maintained on KD showed reduced expression of the hypoxia marker carbonic anhydrase 9, hypoxia inducible factor 1-alpha, and decreased activation of nuclear factor kappa B. Additionally, tumors from animals maintained on KD had reduced tumor microvasculature and decreased expression of vascular endothelial growth factor receptor 2, matrix metalloproteinase-2 and vimentin. Peritumoral edema was significantly reduced in animals fed the KD and protein analyses showed altered expression of zona occludens-1 and aquaporin-4.The KD directly or indirectly alters the expression of several proteins involved in malignant progression and may be a useful tool for the treatment of gliomas.

  11. Stem cells for investigation and treatment of inherited retinal disease.

    Science.gov (United States)

    Tucker, Budd A; Mullins, Robert F; Stone, Edwin M

    2014-09-15

    Vision is the most important human sense. It facilitates every major activity of daily living ranging from basic communication, mobility and independence to an appreciation of art and nature. Heritable diseases of the retina, such as age-related macular degeneration and retinitis pigmentosa, are the leading cause of blindness in the developed world, collectively affecting as many as one-third of all people over the age of 75, to some degree. For decades, scientists have dreamed of preventing vision loss or of restoring the vision of patients affected with retinal degeneration through some type of drug, gene or cell-based transplantation approach. In this review, we will discuss the current literature pertaining to retinal transplantation. We will focus on the use of induced pluripotent stem cells for interrogation of disease pathophysiology, analysis of drug and gene therapeutics and as a source of autologous cells for cell replacement.

  12. Retinal vessels caliber changes after strabismus surgery: results of 6mo follow-up

    Science.gov (United States)

    Li, Ji-Peng; Fu, Jing; Zhou, Jin-Qiong; Wang, Xiao-Zhen; Wang, Wen-Ying; Liu, Ning-Pu

    2016-01-01

    AIM To evaluate the effect of strabismus surgery on retinal vessels calibers with digital color fundus photographs. METHODS Two hundred consecutive strabismus patients underwent surgery, and 118 patients (female/male, 55/63) who finished 6-month follow-up were finally included in this study. Optic disc-centered digital color fundus photographs of both eyes of all patients were taken prior to surgery and 6mo post surgery. The retinal vascular caliber of 116 operated eyes were measured using the computer program IVAN. The operated eyes were divided into 3 groups according to the surgical methods, recession of one muscle, one muscle recession and one muscle folding, one muscle resection and one muscle recession. The effect of number of altered muscles on retinal vessels was analyzed using statistic software SPSS 16.0. RESULTS The mean age was 12.4±8.6y. Averaged central retinal artery equivalent (CRAE) of all patients was 120.31±23.02 µm preoperatively, and 122.87±15.93 µm six months after surgery. Averaged central retinal vein equivalent (CRVE) was 171.11±31.73 µm preoperatively and 175.02±21.00 µm postoperatively. There was no significant difference of averaged CRAE (P=0.22) or CRVE (P=0.19) before and after operation. Averaged arteriole to venule ratio (AVR) was 0.71±0.07 before surgery and 0.70±0.07 after surgery. Comparison of preoperative and postoperative retinal vessels calibers among different surgical groups did not show significant differences. Also, there was no advantage of rectus muscle folding to muscle resection. CONCLUSION Up to 6mo after strabismus surgery, the retinal vascular calibers were not altered. No more than two muscles in one surgery are safe for retinal perfusion. PMID:27672600

  13. AUTOMATIC DETECTION AND CLASSIFICATION OF RETINAL VASCULAR LANDMARKS

    Directory of Open Access Journals (Sweden)

    Hadi Hamad

    2014-06-01

    Full Text Available The main contribution of this paper is introducing a method to distinguish between different landmarks of the retina: bifurcations and crossings. The methodology may help in differentiating between arteries and veins and is useful in identifying diseases and other special pathologies, too. The method does not need any special skills, thus it can be assimilated to an automatic way for pinpointing landmarks; moreover it gives good responses for very small vessels. A skeletonized representation, taken out from the segmented binary image (obtained through a preprocessing step, is used to identify pixels with three or more neighbors. Then, the junction points are classified into bifurcations or crossovers depending on their geometrical and topological properties such as width, direction and connectivity of the surrounding segments. The proposed approach is applied to the public-domain DRIVE and STARE datasets and compared with the state-of-the-art methods using proper validation parameters. The method was successful in identifying the majority of the landmarks; the average correctly identified bifurcations in both DRIVE and STARE datasets for the recall and precision values are: 95.4% and 87.1% respectively; also for the crossovers, the recall and precision values are: 87.6% and 90.5% respectively; thus outperforming other studies.

  14. Purinergic control of vascular tone in the retina.

    Science.gov (United States)

    Kur, Joanna; Newman, Eric A

    2014-02-01

    Purinergic control of vascular tone in the CNS has been largely unexplored. This study examines the contribution of endogenous extracellular ATP, acting on vascular smooth muscle cells, in controlling vascular tone in the in vivo rat retina. Retinal vessels were labelled by i.v. injection of a fluorescent dye and imaged with scanning laser confocal microscopy. The diameters of primary arterioles were monitored under control conditions and following intravitreal injection of pharmacological agents. Apyrase (500 units ml(-1)), an ATP hydrolysing enzyme, dilated retinal arterioles by 40.4 ± 2.8%, while AOPCP (12.5 mm), an ecto-5'-nucleotidase inhibitor that increases extracellular ATP levels, constricted arterioles by 58.0 ± 3.8% (P < 0.001 for both), demonstrating the importance of ATP in the control of basal vascular tone. Suramin (500 μm), a broad-spectrum P2 receptor antagonist, dilated retinal arterioles by 50.9 ± 3.7% (P < 0.001). IsoPPADS (300 μm) and TNP-ATP (50 μm), more selective P2X antagonists, dilated arterioles by 41.0 ± 5.3% and 55.2 ± 6.1% respectively (P < 0.001 for both). NF023 (50 μm), a potent antagonist of P2X1 receptors, dilated retinal arterioles by 32.1 ± 2.6% (P < 0.001). A438079 (500 μm) and AZ10606120 (50 μm), P2X7 antagonists, had no effect on basal vascular tone (P = 0.99 and P = 1.00 respectively). In the ex vivo retina, the P2X1 receptor agonist α,β-methylene ATP (300 nm) evoked sustained vasoconstrictions of 18.7 ± 3.2% (P < 0.05). In vivo vitreal injection of the gliotoxin fluorocitrate (150 μm) dilated retinal vessels by 52.3 ± 1.1% (P < 0.001) and inhibited the vasodilatory response to NF023 (50 μm, 7.9 ± 2.0%; P < 0.01). These findings suggest that vascular tone in rat retinal arterioles is maintained by tonic release of ATP from the retina. ATP acts on P2X1 receptors, although contributions from other P2X and P2Y receptors cannot be ruled out. Retinal glial cells are a possible source of the vasoconstricting ATP.

  15. Detailed Vascular Anatomy of the Human Retina by Projection-Resolved Optical Coherence Tomography Angiography

    Science.gov (United States)

    Campbell, J. P.; Zhang, M.; Hwang, T. S.; Bailey, S. T.; Wilson, D. J.; Jia, Y.; Huang, D.

    2017-01-01

    Optical coherence tomography angiography (OCTA) is a noninvasive method of 3D imaging of the retinal and choroidal circulations. However, vascular depth discrimination is limited by superficial vessels projecting flow signal artifact onto deeper layers. The projection-resolved (PR) OCTA algorithm improves depth resolution by removing projection artifact while retaining in-situ flow signal from real blood vessels in deeper layers. This novel technology allowed us to study the normal retinal vasculature in vivo with better depth resolution than previously possible. Our investigation in normal human volunteers revealed the presence of 2 to 4 distinct vascular plexuses in the retina, depending on location relative to the optic disc and fovea. The vascular pattern in these retinal plexuses and interconnecting layers are consistent with previous histologic studies. Based on these data, we propose an improved system of nomenclature and segmentation boundaries for detailed 3-dimensional retinal vascular anatomy by OCTA. This could serve as a basis for future investigation of both normal retinal anatomy, as well as vascular malformations, nonperfusion, and neovascularization. PMID:28186181

  16. Detailed Vascular Anatomy of the Human Retina by Projection-Resolved Optical Coherence Tomography Angiography

    Science.gov (United States)

    Campbell, J. P.; Zhang, M.; Hwang, T. S.; Bailey, S. T.; Wilson, D. J.; Jia, Y.; Huang, D.

    2017-02-01

    Optical coherence tomography angiography (OCTA) is a noninvasive method of 3D imaging of the retinal and choroidal circulations. However, vascular depth discrimination is limited by superficial vessels projecting flow signal artifact onto deeper layers. The projection-resolved (PR) OCTA algorithm improves depth resolution by removing projection artifact while retaining in-situ flow signal from real blood vessels in deeper layers. This novel technology allowed us to study the normal retinal vasculature in vivo with better depth resolution than previously possible. Our investigation in normal human volunteers revealed the presence of 2 to 4 distinct vascular plexuses in the retina, depending on location relative to the optic disc and fovea. The vascular pattern in these retinal plexuses and interconnecting layers are consistent with previous histologic studies. Based on these data, we propose an improved system of nomenclature and segmentation boundaries for detailed 3-dimensional retinal vascular anatomy by OCTA. This could serve as a basis for future investigation of both normal retinal anatomy, as well as vascular malformations, nonperfusion, and neovascularization.

  17. Bem-estar subjetivo e senso de ajustamento psicológico em idosos que sofreram acidente vascular cerebral: uma revisão Subjective well being and perceived psychological adjustment among old people affected by stroke: a review

    Directory of Open Access Journals (Sweden)

    Dóris Firmino Rabelo

    2006-08-01

    Full Text Available Foi feito um levantamento dos estudos brasileiros e estrangeiros publicados entre 1996 e 2005 que relacionavam bem-estar subjetivo, senso de ajustamento psicológico e acidente vascular cerebral, com o objetivo de identificar variáveis mediadoras dessa relação em idosos. Estudos transversais e prospectivos indicaram que os afetados por acidente vascular cerebral apresentam menor bem-estar subjetivo quando comparados com a população geral. Boa capacidade cognitiva, suporte social efetivo, continuidade de uma ocupação produtiva, manutenção da competência em atividades instrumentais de vida diária e humor positivo são fatores que podem melhorar o bem-estar subjetivo e psicológico. Variáveis que podem piorar o bem-estar subjetivo e psicológico são incapacidade funcional, déficits cognitivos, depressão, dificuldade em restabelecer a identidade e restrição à possibilidade de desempenhar atividades e papéis que contribuem para a auto-definição. O conhecimento das implicações psicológicas de sofrer acidente vascular cerebral pode beneficiar pacientes, familiares e profissionais no gerenciamento do evento.We gathered data from Brazilian and foreign studies published between 1996 and 2005 which related subjective well-being, sense of psychological adjustment and stroke. The objective was identifying mediator variables of this relation among old people. Prospective and cross-sectional studies indicated that those affected by stroke showed less subjective well-being than the general population. Good cognitive capacity, effective social support, continuity of a productive occupation, keeping the competence in instrumental activities of daily living and good mood are factors which can affect positively the subjective and psychological well-being. Variables which can affect negatively the subjective and psychological well-being are functional incapacity, cognitive deficits, depression, difficulty in re-establishing the identity and

  18. Luminosity and contrast normalization in color retinal images based on standard reference image

    Science.gov (United States)

    S. Varnousfaderani, Ehsan; Yousefi, Siamak; Belghith, Akram; Goldbaum, Michael H.

    2016-03-01

    Color retinal images are used manually or automatically for diagnosis and monitoring progression of a retinal diseases. Color retinal images have large luminosity and contrast variability within and across images due to the large natural variations in retinal pigmentation and complex imaging setups. The quality of retinal images may affect the performance of automatic screening tools therefore different normalization methods are developed to uniform data before applying any further analysis or processing. In this paper we propose a new reliable method to remove non-uniform illumination in retinal images and improve their contrast based on contrast of the reference image. The non-uniform illumination is removed by normalizing luminance image using local mean and standard deviation. Then the contrast is enhanced by shifting histograms of uniform illuminated retinal image toward histograms of the reference image to have similar histogram peaks. This process improve the contrast without changing inter correlation of pixels in different color channels. In compliance with the way humans perceive color, the uniform color space of LUV is used for normalization. The proposed method is widely tested on large dataset of retinal images with present of different pathologies such as Exudate, Lesion, Hemorrhages and Cotton-Wool and in different illumination conditions and imaging setups. Results shows that proposed method successfully equalize illumination and enhances contrast of retinal images without adding any extra artifacts.

  19. Effect of retinal ischemia on the non-image forming visual system.

    Science.gov (United States)

    González Fleitas, María Florencia; Bordone, Melina; Rosenstein, Ruth E; Dorfman, Damián

    2015-03-01

    Retinal ischemic injury is an important cause of visual impairment. The loss of retinal ganglion cells (RGCs) is a key sign of retinal ischemic damage. A subset of RGCs expressing the photopigment melanopsin (mRGCs) regulates non-image-forming visual functions such as the pupillary light reflex (PLR), and circadian rhythms. We studied the effect of retinal ischemia on mRGCs and the non-image-forming visual system function. For this purpose, transient ischemia was induced by raising intraocular pressure to 120 mm Hg for 40 min followed by retinal reperfusion by restoring normal pressure. At 4 weeks post-treatment, animals were subjected to electroretinography and histological analysis. Ischemia induced a significant retinal dysfunction and histological alterations. At this time point, a significant decrease in the number of Brn3a(+) RGCs and in the anterograde transport from the retina to the superior colliculus and lateral geniculate nucleus was observed, whereas no differences in the number of mRGCs, melanopsin levels, and retinal projections to the suprachiasmatic nuclei and the olivary pretectal nucleus were detected. At low light intensity, a decrease in pupil constriction was observed in intact eyes contralateral to ischemic eyes, whereas at high light intensity, retinal ischemia did not affect the consensual PLR. Animals with ischemia in both eyes showed a conserved locomotor activity rhythm and a photoentrainment rate which did not differ from control animals. These results suggest that the non-image forming visual system was protected against retinal ischemic damage.

  20. Acute retinal necrosis

    Directory of Open Access Journals (Sweden)

    Hugo Hernán Ocampo

    2009-12-01

    Full Text Available Purpose: Clinical features in a case of acute retinal necrosis are described as well as its diagnostic approach and response to early treatment. Methods: This is a descriptive and retrospective study case report of a 26 year old male patient who arrived to the emergency room with a three day history of sudden visual loss in the right eye (RE. At initial evaluation a visual acuity of hand movements in the RE, 20/15 in the left eye (LE and a right relative afferent pupillary defect were found. Fundoscopy revealed profuse soft exudates and hemorrhages involving posterior pole, inferior hemiretina and superotemporal periphery. Infectious workup and fluoresceinic angiography were made and positive serologies for herpes virus types 1 and 2, without HIV, were found. A diagnosis of acute retinal necrosis was made and treatment with intravenous valgancyclovir for two weeks and intra-vitreous triamcinolone for severe vasculitis, was given. Then a 3 months treatment with oral antiviral agents was prescribed. Results: Patient’s evolution showed improvement with treatment and at two and a half months of follow up, visual acuity was 20/50 in the right eye, normal slit lamp examination, tonometry of 12 mm Hg and fundoscopy improved when compared to initial pictures.Conclusions: A high index of suspicion is needed for diagnosing ARN taking into account clinical findings. Prompt intravenous and intra-vitreous treatments are needed to achieve good clinical and functional outcomes and to avoid central nervous system complications.

  1. Bilateral Central Retinal Vein Occlusions Combined with Artery Occlusions in A Patient with Acquired Immune Deficiency Syndrome

    Institute of Scientific and Technical Information of China (English)

    Feng Wen; Xuemei Chen; Haitai Li; Ruiduan Liao; Dezheng Wu

    2002-01-01

    Purpose: This is the first report of a bilateral nonischemic central retinal vein occlusionscombined with artery occlusions in a patient with acquired immune deficiency syndrome(AIDS). Methods: Case report. Results: A 22-year-old Chinese(male) with a positive human immunodeficiency virus(HIV) infection developed bilateral nonischemic central retinal vein occlusions combinedwith artery occlusions and severe vision loss. The manifestations of the fundus andfluorescein angiography were similar in both eyes.Conclusion: This case report provides the evidences that central retinal vein and arteryocclusions are probably part of the spectrum of AIDS vascular diseases.

  2. The relaxing effect of perivascular tissue on porcine retinal arterioles in vitro is mimicked by N-methyl-D-aspartate and is blocked by prostaglandin synthesis inhibition

    DEFF Research Database (Denmark)

    Holmgaard, Kim; Aalkjaer, Christian; Lambert, John D C;

    2007-01-01

    PURPOSE: Retinal hyperperfusion resulting from disturbances in the regulation of arteriolar tone is involved in the pathophysiology of a variety of retinal diseases. The mechanisms underlying this regulation of tone involve cellular components in both the vascular wall and the perivascular tissue....... However, previous in vitro studies of the influence of perivascular retinal tissue on retinal tone regulation have been hampered by the release of an endogenous relaxing factor that renders the arteriole insensitive to vasoconstrictors. The purpose of the present study was to test whether N......-methyl-D-aspartate (NMDA) and gamma-amino butyric acid (GABA) receptors, and a cyclooxygenase (COX) product influence this effect of perivascular retinal tissue in vitro. METHODS: Porcine retinal arterioles were mounted in a wire myograph for isometric force measurements. The contractile effect of the prostaglandin...

  3. Contribution of nitric oxide synthase isoforms to cholinergic vasodilation in murine retinal arterioles.

    Science.gov (United States)

    Gericke, Adrian; Goloborodko, Evgeny; Sniatecki, Jan J; Steege, Andreas; Wojnowski, Leszek; Pfeiffer, Norbert

    2013-04-01

    Nitric oxide synthases (NOSs) are critically involved in regulation of ocular perfusion. However, the contribution of the individual NOS isoforms to vascular responses is unknown in the retina. Because some previous findings suggested an involvement of inducible nitric oxide synthase (iNOS) in the regulation of retinal vascular tone, a major goal of the present study was to examine the hypothesis that iNOS is involved in mediating cholinergic vasodilation responses of murine retinal arterioles. Another subject of this study was to test the contribution of the other two NOS isoforms, neuronal (nNOS) and endothelial NOS (eNOS), to cholinergic retinal arteriole responses. Expression of individual NOS isoforms was determined in murine retinal arterioles using real-time PCR. All three NOS isoforms were expressed in retinal arterioles. However, eNOS mRNA was found to be most, and iNOS mRNA least abundant. To examine the functional relevance of iNOS for mediating vascular responses, retinal vascular preparations from gene-targeted iNOS-deficient mice (iNOS-/-) and wild-type mice were studied in vitro. Changes in luminal vessel diameter in response to the thromboxane mimetic 9,11-dideoxy-9α,11α-methanoepoxy prostaglandin F2α (U-46619), the endothelium-dependent vasodilator acetylcholine, and the nitric oxide donor nitroprusside were measured by video microscopy. To determine the contribution of individual NOS isoforms to cholinergic vasodilation responses, retinas from iNOS-/- and wild-type mice were incubated with Nω-nitro-l-arginine methyl ester (l-NAME), a non-isoform-selective inhibitor of NOS, 7-nitroindazole, a selective nNOS blocker and aminoguanidine, a selective iNOS inhibitor. U-46619 evoked concentration-dependent vasoconstriction that was similar in retinal arterioles from iNOS-/- and wild-type mice. In retinal arterioles preconstricted with U-46619, acetylcholine and nitroprusside produced dose-dependent dilation that did not differ between iNOS-/- and

  4. Recent developments in retinal lasers and delivery systems

    Directory of Open Access Journals (Sweden)

    Naresh Kumar Yadav

    2014-01-01

    Full Text Available Photocoagulation is the standard of care for several ocular disorders and in particular retinal conditions. Technology has offered us newer lasing mediums, wavelengths and delivery systems. Pattern scan laser in proliferative diabetic retinopathy and diabetic macular edema allows laser treatment that is less time consuming and less painful. Now, it is possible to deliver a subthreshold micropulse laser that is above the threshold of biochemical effect but below the threshold of a visible, destructive lesion thereby preventing collateral damage. The advent of solid-state diode yellow laser allows us to treat closer to the fovea, is more effective for vascular structures and offers a more uniform effect in patients with light or irregular fundus pigmentation. Newer retinal photocoagulation options along with their advantages is discussed in this review.

  5. Treatment of Laser-Induced Retinal Injuries

    Science.gov (United States)

    1989-06-29

    Distribution List (enclosed) bI’TF rruIoN STATEMEN A Approved for publi reljaso Disatbunon Unlimited TREATMENT OF LASER-INDUCED RETINAL INJURIES FINAL...suprathreshold retinal laser lesions II. Subthreshold retinal laser lesions III. Effect of steroid treatment on laser-induced retinal injury Discussion and...In the present study we investigated the effect of corticosteroid treatment of argon laser-induced retinal injury on vitreal accumulation of both

  6. On conditions of negativity of friction resistance for non-stationary modes of blood flow and possible mechanism of affecting of environmental factors on energy effectiveness of cardio-vascular system functioning

    CERN Document Server

    Chefranov, S G

    2013-01-01

    It is shown that initiated by action of molecular viscosity impulse flow, directed usually from the moving fluid to limiting it solid surface, can, under certain conditions, turn to zero and get negative values in the case of non-stationary flow caused by alternating in time longitudinal (along the pipe axis) pressure gradient. It is noted that this non-equilibrium mechanism of negative friction resistance in the similar case of pulsating blood flow in the blood vessels, in addition to the stable to turbulent disturbances swirled blood flow structure providing, can also constitute hydro-mechanical basis of the observed but not explained yet paradoxically high energy effectiveness of the normal functioning of the cardio-vascular system (CVS). We consider respective mechanism of affecting on the stability of the normal work of CVS by environmental variable factors using shifting of hydro-dynamic mode with negative resistance realization range boundaries and variation of linear hydro-dynamic instability leading ...

  7. 复方血栓通对人视网膜血管内皮细胞抗氧化损伤的保护作用及其机制%Protective effects and mechanism of fufang xueshuantong on tert-butyl hydroperoxide-induced injury of human retinal vascular endothelial cells

    Institute of Scientific and Technical Information of China (English)

    陈晓云; 李建桥; 朱晓波; 肖伟; 黄娟; 李涛; 唐仕波; 罗燕

    2011-01-01

    Background Oxidative damage may cause the functional dysfunction and death of retinal vascular endothelial cells(RVECs),and further leads to the development of retinal vascular diseases.Fufang xueshuantong has a therapeutic effect on retinal vascular diseases,but little is known about its molecular mechanism.Objective The goal of this study was to investigate the protective effects and mechanism of fufang xueshuantong on injury of human RVECs induced by tert-butyl hydroperoxide(t-BHP).Methods Human RVECs were isolated from healthy donor eyes and primarily cultured and then identified by flow cytometry.The third to fifth generations of cells were used in this experiments.The fufang xueshuantong solution of 0.0625,0.1250,0.2500,0.5000 and 1.0000 g/L were added in the cuhure plate with 5 × 104/L cells respectively in the experimental groups,and t-BHP of 75,100,200 and 300 μ.mol/L were added in the model control groups.MTT was used to detect the A490and survival rate of RVECs.The apoptotic rate and death rate of the cells were evaluated by double staining of Annexin V-FITC/PI.Morphology of human RVECs were examined using invert microscopy and Hoechst33258 staining.The expressions of nitro tyrosine (a marker of oxidative damage of protein)and 8-OHdG(a marker of oxidative damage of DNA)in human RVECs were assessed by the immunofluorescence staining.Western blot was used to detect the expressions of nuclear factorkappa B(NF-KB),p53,bcl-2 and bax after 6,12,24 hours t-BHP action.This study was approved by the Ethic Committee of Zhongshan Ophthalmic Center.Results No significant difference was found in A490value among the normal control group,0.0625,0.1250,0.2500,0.5000 and 1.0000 g/L fufang xueshuantong groups(F =1.989,P>0.05).The survival rates of the cells were lower in 75,100,200 and 300 μmol/L t-BHP groups compared with corresponding fufang xueshuantong groups(t =14.57,13.82,21.51,32.64,P< 0.01).The percentages of normal cells were evidently lower in 75

  8. Rhegmatogenous retinal detachment: current opinion

    Directory of Open Access Journals (Sweden)

    T. A. Avanesova

    2015-03-01

    Full Text Available Rhegmatogenous retinal detachment (RRD is a severe ocular disorder which requires prompt treatment to prevent low vision and blindness. It is also a significant socio-economic problem as 84% of RDD patients are able-bodied. RRD grading systems (including current Machemer grading system, risk factors, and pathogenesis are reviewed. The role of proliferative vitreoretinopathy in RDD pathogenesis and recurrence is described. Macula involvement determines RDD outcome. Optical coherence tomography (OCT provides the study of retina anatomy and the analysis of parameters that affect post-op best corrected visual acuity, i.e., defects of the junction between inner segments and outer segments (IS/OS, the integrity of external (ELM and internal limiting membrane (ILM, outer nuclear layer thickness (ONLT etc. Fluorescent angiography allows to understand the reasons for low vision in anatomically successful RDD surgery. Scleral buckling, balloon buckling, pneumatic retinopexy, vitrectomy, cryopexy, and laser coagulation are important tools in surgical armamentarium. In recent years, vitrectomy is growing in popularity for RDD treatment. Criteria for procedure selection and surgical success rate in phakic and pseudophakic eyes are discussed. The outcomes of vitrectomy with air/gas and silicone oil tamponade are compared. Bimanual vitrectomy benefits are discussed. 

  9. Rhegmatogenous retinal detachment: current opinion

    Directory of Open Access Journals (Sweden)

    T. A. Avanesova

    2015-01-01

    Full Text Available Rhegmatogenous retinal detachment (RRD is a severe ocular disorder which requires prompt treatment to prevent low vision and blindness. It is also a significant socio-economic problem as 84% of RDD patients are able-bodied. RRD grading systems (including current Machemer grading system, risk factors, and pathogenesis are reviewed. The role of proliferative vitreoretinopathy in RDD pathogenesis and recurrence is described. Macula involvement determines RDD outcome. Optical coherence tomography (OCT provides the study of retina anatomy and the analysis of parameters that affect post-op best corrected visual acuity, i.e., defects of the junction between inner segments and outer segments (IS/OS, the integrity of external (ELM and internal limiting membrane (ILM, outer nuclear layer thickness (ONLT etc. Fluorescent angiography allows to understand the reasons for low vision in anatomically successful RDD surgery. Scleral buckling, balloon buckling, pneumatic retinopexy, vitrectomy, cryopexy, and laser coagulation are important tools in surgical armamentarium. In recent years, vitrectomy is growing in popularity for RDD treatment. Criteria for procedure selection and surgical success rate in phakic and pseudophakic eyes are discussed. The outcomes of vitrectomy with air/gas and silicone oil tamponade are compared. Bimanual vitrectomy benefits are discussed. 

  10. Retinal Microvascular Abnormalities in Neurofibromatosis Type 1 Associated with Congenital Retinal Macrovessels

    Science.gov (United States)

    Makino, Shinji; Endoh, Katsuhisa; Tampo, Hironobu

    2013-01-01

    Here, we report a case of retinal microvascular abnormalities in a patient with neurofibromatosis type 1 (NF1) associated with congenital retinal macrovessels. An abnormal retinal macrovessel, crossing the macula horizontally, was detected in the right eye. Additionally, retinal microvascular abnormalities were detected. Eight years after the initial visit, the retinal microvascular abnormalities were noted to have changed substantially. We speculate that retinal microvascular abnormalities in NF1 may change dynamically over the years. PMID:23781366

  11. Retinal Microvascular Abnormalities in Neurofibromatosis Type 1 Associated with Congenital Retinal Macrovessels

    Directory of Open Access Journals (Sweden)

    Shinji Makino

    2013-01-01

    Full Text Available Here, we report a case of retinal microvascular abnormalities in a patient with neurofibromatosis type 1 (NF1 associated with congenital retinal macrovessels. An abnormal retinal macrovessel, crossing the macula horizontally, was detected in the right eye. Additionally, retinal microvascular abnormalities were detected. Eight years after the initial visit, the retinal microvascular abnormalities were noted to have changed substantially. We speculate that retinal microvascular abnormalities in NF1 may change dynamically over the years.

  12. [Retinal vasculitis in lupic disease].

    Science.gov (United States)

    Brissaud, P; Laroche, L; Krulik, M; Prier, A M; Saraux, H; Canuel, C; Debray, J

    1985-01-01

    Three cases of retinal vasculitis in SLE-type diseases are reported. The first was central retinal vein occlusion occurring during clinical remission of SLE in a 55 year old black female. Prednisone maintenance therapy was unchanged and visual loss rapidly regressed with heparin therapy. The second case was a 33 year old black female in whom SLE was discovered following relapsing bilateral optic neuritis. A progressive visual improvement was obtained with high dose of prednisone (1 mg/kg/day). The third cas was a 17 year old white girl with retinal vasculitis. She had an unclassified connective tissue disease inaugurated by optic neuritis at the age of 10. High dose prednisone (1 mg/kg/day) was effective on the visual loss. Retinal vasculitis lesions in SLE and their therapy are reviewed.

  13. 3-D segmentation of retinal blood vessels in spectral-domain OCT volumes of the optic nerve head

    Science.gov (United States)

    Lee, Kyungmoo; Abràmoff, Michael D.; Niemeijer, Meindert; Garvin, Mona K.; Sonka, Milan

    2010-03-01

    Segmentation of retinal blood vessels can provide important information for detecting and tracking retinal vascular diseases including diabetic retinopathy, arterial hypertension, arteriosclerosis and retinopathy of prematurity (ROP). Many studies on 2-D segmentation of retinal blood vessels from a variety of medical images have been performed. However, 3-D segmentation of retinal blood vessels from spectral-domain optical coherence tomography (OCT) volumes, which is capable of providing geometrically accurate vessel models, to the best of our knowledge, has not been previously studied. The purpose of this study is to develop and evaluate a method that can automatically detect 3-D retinal blood vessels from spectral-domain OCT scans centered on the optic nerve head (ONH). The proposed method utilized a fast multiscale 3-D graph search to segment retinal surfaces as well as a triangular mesh-based 3-D graph search to detect retinal blood vessels. An experiment on 30 ONH-centered OCT scans (15 right eye scans and 15 left eye scans) from 15 subjects was performed, and the mean unsigned error in 3-D of the computer segmentations compared with the independent standard obtained from a retinal specialist was 3.4 +/- 2.5 voxels (0.10 +/- 0.07 mm).

  14. Retinal layer location of increased retinal thickness in eyes with subclinical and clinical macular edema in diabetes type 2

    DEFF Research Database (Denmark)

    Bandello, Francesco; Tejerina, Amparo Navea; Vujosevic, Stela

    2015-01-01

    PURPOSE: To identify the retinal layer predominantly affected in eyes with subclinical and clinical macular edema in diabetes type 2. METHODS: A cohort of 194 type 2 diabetic eyes/patients with mild nonproliferative diabetic retinopathy (ETDRS levels 20/35) were examined with Cirrus spectral-doma...

  15. Vitreous inflammatory factors and serous retinal detachment in central retinal vein occlusion: a case control series

    Directory of Open Access Journals (Sweden)

    Noma Hidetaka

    2011-12-01

    Full Text Available Abstract Background This study investigated whether the vitreous fluid levels of soluble vascular endothelial growth factor receptor-2 (sVEGFR-2, pigment epithelium-derived factor (PEDF, and soluble intercellular adhesion molecule 1 (sICAM-1 were associated with the occurrence of serous retinal detachment (SRD in patients with central retinal vein occlusion (CRVO. Methods We recruited 33 patients with CRVO and macular edema, as well as 18 controls with nonischemic ocular diseases. Eighteen of the 33 patients with CRVO showed SRD on optical coherence tomography of the macula (defined as subretinal accumulation of fluid with low reflectivity, while the other 15 patients only had cystoid macular edema (CME, defined as hyporeflective intraretinal cavities. Retinal ischemia was evaluated by measuring the area of capillary non-perfusion using fluorescein angiography and the public domain Scion Image program, while central macular thickness (CMT was examined by optical coherence tomography. Vitreous fluid samples were obtained during pars plana vitrectomy and levels of the target molecules were measured by enzyme-linked immunosorbent assay. Results Ischemia was significantly more common in the SRD group (17/18 patients than in the CME group (5/15 patients (P ptrendptrend = 0.019. On the other hand, the vitreous fluid level of PEDF showed a significant decrease across the three groups (56.4 ± 40.0 ng/ml, 24.3 ± 17.3 ng/ml, and 16.4 ± 12.6 ng/ml, respectively, ptrend Conclusions Higher levels of inflammatory factors (sICAM-1 and sVEGFR-2 and lower levels of anti-inflammatory PEDF were observed in macular edema patients with SRD, suggesting that inflammation plays a key role in determining the severity of CRVO.

  16. Automated Localization of Optic Disc in Retinal Images

    Directory of Open Access Journals (Sweden)

    Deepali A.Godse

    2013-03-01

    Full Text Available An efficient detection of optic disc (OD in colour retinal images is a significant task in an automated retinal image analysis system. Most of the algorithms developed for OD detection are especially applicable to normal and healthy retinal images. It is a challenging task to detect OD in all types of retinal images, that is, normal, healthy images as well as abnormal, that is, images affected due to disease. This paper presents an automated system to locate an OD and its centre in all types of retinal images. The ensemble of steps based on different criteria produces more accurate results. The proposed algorithm gives excellent results and avoids false OD detection. The technique is developed and tested on standard databases provided for researchers on internet, Diaretdb0 (130 images, Diaretdb1 (89 images, Drive (40 images and local database (194 images. The local database images are collected from ophthalmic clinics. It is able to locate OD and its centre in 98.45% of all tested cases. The results achieved by different algorithms can be compared when algorithms are applied on same standard databases. This comparison is also discussed in this paper which shows that the proposed algorithm is more efficient.

  17. 轴突导向因子netrin-1对早期糖尿病大鼠血视网膜屏障的影响%The effect of netrin-1 on the retinal vascular permeability in early diabetic retinopathy rats

    Institute of Scientific and Technical Information of China (English)

    周贤慧; 孟旭霞; 孙运波; 胡迭; 郭庆敏

    2015-01-01

    视网膜IA值与正常对照组比较,差异有统计学意义(t=12.87,P=0.00).EB渗漏试验结果显示,DM+ BSS组、DM+ netrin-1低剂量、DM+ netrin-1高剂量组间大鼠视网膜EB渗漏量比较,差异有统计意义(F=179.69,P=0.00);DM+ netrin-1低剂量组大鼠视网膜EB渗漏量与DM+netrin-1高剂量组比较,差异有统计学意义(t=12.73,P=0.00).结论 玻璃体腔注射外源性netrin-1对早期DM大鼠BRB有保护作用;这种保护作用可能是通过抑制视网膜occludin的减少实现.%Objective To explore the effect and mechanism of netrin-1 on blood-retinal barrier permeability in diabetes mellitus (DM) rats.Methods Eighty Sprague-Dawley rats were randomly divided into the normal control group,DM+balanced salt solution (BSS) group,DM+netrin-1 low dose group and DM+ netrin-1 high dose group,with 20 rats in each group.DM rats were induced by intraperitoneal injection of streptozocin (STZ).These rats were feed with high sugar and fat for 3 months after STZ injection.All rats were sacrificed at 1 month after intravitreal injection.RetinM vascular permeability was measured by Evans blue.The expression level of occludin was determined by immunohistochemistry.Hematoxylin-eosin (HE) staining of retina was used to observe the pathological change of DM and the level of occludin mRNA was analyzed by real-time fluorescence quantitative reverse transcription polymerase chain reaction (RT-PCR).Five rats of each group.Results HE staining of retina showed that the degree of edema and vascularization in DM+ netrin 1 high dose group was better than DM+BSS group.Staining of occludin in retina was limited to nerve fiber layer,ganglion cells,inner plexiform layer and inner nuclear layer in normal rats,but in DM+BSS group,the color of staining positive of occludin was lighter and more reduced.However,DM+ netrin 1 group oceludin staining was deepen and enlarged.The result of RT-PCR showed that the expression of occludin mRNA in other three groups was less than

  18. Retinal arterial occlusion in Takayasu′s arteritis

    Directory of Open Access Journals (Sweden)

    Kaushik Sushmita

    2005-01-01

    Full Text Available Takayasu′s arteritis is an auto-immune disorder of the large and medium-sized arteries, commonly involving the heart and its main vessels. It is now recognised that the inflammatory process of the large arteries affects regions of the walls supplied by the vasa vasorum, suggesting that primary small vessel involvement may contribute to the development of the clinico-pathological features of Takayasu aorto-arteritis. Classical ophthalmic features of the disease result from reduced ocular perfusion, which manifests as hypoxic retinal changes such as microaneurysms, arterio-venous anastomosis and non-perfused areas. Branch retinal artery occlusion has not been previously described in this condition. This case illustrates retinal arterial occlusion as the presenting feature of Takayasu′s arteritis.

  19. Arteriovenous Malformations and Other Vascular Lesions of the Central Nervous System

    Science.gov (United States)

    ... Malformations and Other Vascular Lesions of the Central Nervous System Fact Sheet Table of Contents (click to jump ... other types of vascular lesions affect the central nervous system? What causes vascular lesions? How are AVMs and ...

  20. Filling in the retinal image

    Science.gov (United States)

    Larimer, James; Piantanida, Thomas

    1990-01-01

    The optics of the eye form an image on a surface at the back of the eyeball called the retina. The retina contains the photoreceptors that sample the image and convert it into a neural signal. The spacing of the photoreceptors in the retina is not uniform and varies with retinal locus. The central retinal field, called the macula, is densely packed with photoreceptors. The packing density falls off rapidly as a function of retinal eccentricity with respect to the macular region and there are regions in which there are no photoreceptors at all. The retinal regions without photoreceptors are called blind spots or scotomas. The neural transformations which convert retinal image signals into percepts fills in the gaps and regularizes the inhomogeneities of the retinal photoreceptor sampling mosaic. The filling-in mechamism plays an important role in understanding visual performance. The filling-in mechanism is not well understood. A systematic collaborative research program at the Ames Research Center and SRI in Menlo Park, California, was designed to explore this mechanism. It was shown that the perceived fields which are in fact different from the image on the retina due to filling-in, control some aspects of performance and not others. Researchers have linked these mechanisms to putative mechanisms of color coding and color constancy.

  1. Retinal implants: a systematic review.

    Science.gov (United States)

    Chuang, Alice T; Margo, Curtis E; Greenberg, Paul B

    2014-07-01

    Retinal implants present an innovative way of restoring sight in degenerative retinal diseases. Previous reviews of research progress were written by groups developing their own devices. This systematic review objectively compares selected models by examining publications describing five representative retinal prostheses: Argus II, Boston Retinal Implant Project, Epi-Ret 3, Intelligent Medical Implants (IMI) and Alpha-IMS (Retina Implant AG). Publications were analysed using three criteria for interim success: clinical availability, vision restoration potential and long-term biocompatibility. Clinical availability: Argus II is the only device with FDA approval. Argus II and Alpha-IMS have both received the European CE Marking. All others are in clinical trials, except the Boston Retinal Implant, which is in animal studies. Vision restoration: resolution theoretically correlates with electrode number. Among devices with external cameras, the Boston Retinal Implant leads with 100 electrodes, followed by Argus II with 60 electrodes and visual acuity of 20/1262. Instead of an external camera, Alpha-IMS uses a photodiode system dependent on natural eye movements and can deliver visual acuity up to 20/546. Long-term compatibility: IMI offers iterative learning; Epi-Ret 3 is a fully intraocular device; Alpha-IMS uses intraocular photosensitive elements. Merging the results of these three criteria, Alpha-IMS is the most likely to achieve long-term success decades later, beyond current clinical availability.

  2. Retinal prosthesis for the blind.

    Science.gov (United States)

    Margalit, Eyal; Maia, Mauricio; Weiland, James D; Greenberg, Robert J; Fujii, Gildo Y; Torres, Gustavo; Piyathaisere, Duke V; O'Hearn, Thomas M; Liu, Wentai; Lazzi, Gianluca; Dagnelie, Gislin; Scribner, Dean A; de Juan, Eugene; Humayun, Mark S

    2002-01-01

    Most of current concepts for a visual prosthesis are based on neuronal electrical stimulation at different locations along the visual pathways within the central nervous system. The different designs of visual prostheses are named according to their locations (i.e., cortical, optic nerve, subretinal, and epiretinal). Visual loss caused by outer retinal degeneration in diseases such as retinitis pigmentosa or age-related macular degeneration can be reversed by electrical stimulation of the retina or the optic nerve (retinal or optic nerve prostheses, respectively). On the other hand, visual loss caused by inner or whole thickness retinal diseases, eye loss, optic nerve diseases (tumors, ischemia, inflammatory processes etc.), or diseases of the central nervous system (not including diseases of the primary and secondary visual cortices) can be reversed by a cortical visual prosthesis. The intent of this article is to provide an overview of current and future concepts of retinal and optic nerve prostheses. This article will begin with general considerations that are related to all or most of visual prostheses and then concentrate on the retinal and optic nerve designs. The authors believe that the field has grown beyond the scope of a single article so cortical prostheses will be described only because of their direct effect on the concept and technical development of the other prostheses, and this will be done in a more general and historic perspective.

  3. The marrow haemopoietic stem cells mobilization affecting the retinal neovascularization induced by laser%骨髓干细胞动员对激光诱导视网膜新生血管产生的影响

    Institute of Scientific and Technical Information of China (English)

    赖铭莹; 应方微

    2010-01-01

    目的 了解高能激光诱导兔实验性新生血管过程中给予骨髓动员对新生血管形成的影响.方法 取高能激光光凝10只有色家兔(20只眼)视网膜后7d,6只兔给予连续皮下注射GMFS共5d进行骨髓动员,并以Brdu标记外周血的单个核细胞,在动员前,动员后1周、2周及3周分别取激光光凝斑处的球壁进行常规HE染色,并行免疫组化检测局部Brdu分布,对照组光凝后21d取光凝斑处的球壁做为对照.结果 骨髓动员兔的视网膜激光光凝斑处视网膜新生血管少见,主要为纤维性修复,纤维瘢痕收缩;对照组激光诱导视网膜形成明显的新生血管.免疫组化显示激光动员兔激光斑处可见Brdu阳性的细胞,对照组则为阴性.结论 骨髓动员能够抑制高能激光诱导的兔视网膜新生血管形成,促进纤维组织生长,动员的细胞可能直接参与了纤维修复.%Objective To understand the effect of the marrow haemopoietic stem cells mobilization during the rabbits' retinal neovascularization induced by laser.Methods Seven days after 10 color rabbits (20 eyes) received high-energy Argon laser to induce the retinal neovascularization, 6 of them injected subcutaneous with GMFS for 5 days continuously, then the single nucleolus cells in the blood were marked with Brdu, and last, the retina of the laser light spots before and 1 to 3 weeks after marrow mobilization were obtained to stain with HE and observe the disposition of Brdu by the immunohistochemistry, the other 4 rabbits' retina were treated as the contrast 21 days after laser light exposure.Results The retina new vessels were less, fibrous repaired and scar formed in morrow mobilization group than that of the contrast, and the Brdu was positive, while the contrast was negative.Conclusions The marrow mobilization can reduce the retinal neovascularization induced by laser, and develop fibrous tissue growing, perhaps the cells of mobilization joined in the fibrous repair

  4. Zebrafish model for the genetic basis of X-linked retinitis pigmentosa.

    Science.gov (United States)

    Raghupathy, Rakesh Kotapati; McCulloch, Daphne L; Akhtar, Saeed; Al-mubrad, Turki M; Shu, Xinhua

    2013-03-01

    Retinitis pigmentosa (RP) affects 1/4000 individuals in most populations, and X-linked RP (XLRP) is one of the most severe forms of human retinal degeneration. Mutations in both the retinitis pigmentosa GTPase regulator (RPGR) gene and retinitis pigmentosa 2 (RP2) gene account for almost all cases of XLRP. The functional roles of both RPGR and RP2 in the pathogenesis of XLRP are unclear. Due to the surprisingly high degree of functional conservation between human genes and their zebrafish orthologues, the zebrafish has become an important model for human retinal disorders. In this brief review, we summarize the functional characterization of XLRP-causing genes, RPGR and RP2, in zebrafish, and highlight recent studies that provide insight into the cellular functions of both genes. This will not only shed light on disease mechanisms in XLRP but will also provide a solid platform to test RP-causing mutants before proposing XLRP gene therapy trials.

  5. Recent Advances towards the Clinical Application of Stem Cells for Retinal Regeneration

    Directory of Open Access Journals (Sweden)

    G. Astrid Limb

    2012-10-01

    Full Text Available Retinal degenerative diseases constitute a major cause of irreversible blindness in the world. Stem cell-based therapies offer hope for these patients at risk of or suffering from blindness due to the deterioration of the neural retina. Various sources of stem cells are currently being investigated, ranging from human embryonic stem cells to adult-derived induced pluripotent stem cells as well as human Müller stem cells, with the first clinical trials to investigate the safety and tolerability of human embryonic stem cell-derived retinal pigment epithelium cells having recently commenced. This review aims to summarize the latest advances in the development of stem cell strategies for the replacement of retinal neurons and their supportive cells, the retinal pigment epithelium (RPE affected by retinal degenerative conditions. Particular emphasis will be given to the advances in stem cell transplantation and the challenges associated with their translation into clinical practice.

  6. Honokiol inhibits pathological retinal neovascularization in oxygen-induced retinopathy mouse model

    Energy Technology Data Exchange (ETDEWEB)

    Vavilala, Divya Teja [Division of Pharmaceutical Sciences, School of Pharmacy, University of Missouri-Kansas City, MO (United States); O’Bryhim, Bliss E. [Department of Ophthalmology, University of Kansas Medical Center, Kansas City, KS (United States); Ponnaluri, V.K. Chaithanya [Division of Pharmaceutical Sciences, School of Pharmacy, University of Missouri-Kansas City, MO (United States); White, R. Sid; Radel, Jeff [Department of Ophthalmology, University of Kansas Medical Center, Kansas City, KS (United States); Symons, R.C. Andrew [Department of Ophthalmology, University of Kansas Medical Center, Kansas City, KS (United States); Ophthalmology Department, Royal Melbourne Hospital, University of Melbourne, Victoria (Australia); Department of Surgery, Royal Melbourne Hospital, University of Melbourne, Victoria (Australia); Mukherji, Mridul, E-mail: mukherjim@umkc.edu [Division of Pharmaceutical Sciences, School of Pharmacy, University of Missouri-Kansas City, MO (United States)

    2013-09-06

    Highlights: •Aberrant activation of HIF pathway is the underlying cause of ischemic neovascularization. •Honokiol has better therapeutic index as a HIF inhibitor than digoxin and doxorubicin. •Daily IP injection of honokiol in OIR mouse model reduced retinal neovascularization. •Honokiol also prevents vaso-obliteration, the characteristic feature of the OIR model. •Honokiol enhanced physiological revascularization of the retinal vascular plexuses. -- Abstract: Aberrant activation of the hypoxia inducible factor (HIF) pathway is the underlying cause of retinal neovascularization, one of the most common causes of blindness worldwide. The HIF pathway also plays critical roles during tumor angiogenesis and cancer stem cell transformation. We have recently shown that honokiol is a potent inhibitor of the HIF pathway in a number of cancer and retinal pigment epithelial cell lines. Here we evaluate the safety and efficacy of honokiol, digoxin, and doxorubicin, three recently identified HIF inhibitors from natural sources. Our studies show that honokiol has a better safety to efficacy profile as a HIF inhibitor than digoxin and doxorubicin. Further, we show for the first time that daily intraperitoneal injection of honokiol starting at postnatal day (P) 12 in an oxygen-induced retinopathy (OIR) mouse model significantly reduced retinal neovascularization at P17. Administration of honokiol also prevents the oxygen-induced central retinal vaso-obliteration, characteristic feature of the OIR model. Additionally, honokiol enhanced physiological revascularization of the retinal vascular plexuses. Since honokiol suppresses multiple pathways activated by HIF, in addition to the VEGF signaling, it may provide advantages over current treatments utilizing specific VEGF antagonists for ocular neovascular diseases and cancers.

  7. XLPRA: A canine retinal degeneration inherited as an X-linked trait

    Energy Technology Data Exchange (ETDEWEB)

    Acland, G.M.; Blanton, S.H.; Hershfield, B.; Aguirre, G.D.

    1994-08-01

    Breeding studies are reported of a previously undescribed hereditary retinal degeneration identified in the Siberian Husky breed of dog. This disorder clinically resembles the previously reported autosomal recessive canine hereditary retinal degenerations collectively termed progressive retinal atrophy (PRA). However, the pedigree of the propositus, a male Siberian Husky, exhibited an X-linked pattern of transmission. This dog was outcrossed to three phenotypically normal female laboratory Beagles and two of their F1 daughters were bred to a phenotypically normal male Beagle, producing affected males in the F2 generation. Subsequent inbreedings produced further affected males and affected females as well. X-linked transmission was established by exclusion of alternative modes of inheritance and, consequently, the disease has been termed X-linked progressive retinal atrophy (XLPRA). This is the first reported X-linked retinal degeneration in an animal. Because of the many similarities of PRA in dogs to retinitis pigmentosa (RP) in humans, this new disease may not only represent the first animal model of X-linked RP (XLRP) but may well be a true homolog of one of the XLRP loci (RP2, RP3, RP6). It is the first retinal degeneration in dogs that can be assigned to an identified canine chromosome, and the first for which linkage mapping offers a realistic approach to proceed by positional cloning towards identifying the responsible gene. 58 refs., 1 fig., 3 tabs.

  8. Retinal vessel caliber as a potential marker of treatment outcome in patients with proliferative diabetic retinopathy

    DEFF Research Database (Denmark)

    Vergmann, Anna Stage; Torp, Thomas Lee; Lundberg, Kristian;

    Title of abstract: Retinal vessel caliber as a potential marker of treatment outcome in patients with proliferative diabetic retinopathy Design of study: Three months prospective, interventional clinical study. Purpose: The retinal vascular tree can be measured non-invasively and summarized...... diagnosed patients with PDR were included. At baseline, all patients received standard PRP treatment by a navigated laser (NAVILAS®, OD-OS GmbH, Berlin, Germany). Wide-field fundus fluorescein angiography (Optomap, Optos PLC., Dunfermline, Scotland, UK) was performed at BL to verify diagnosis of PDR...

  9. Calpain inhibitors reduce retinal hypoxia in ischemic retinopathy by improving neovascular architecture and functional perfusion.

    Science.gov (United States)

    Hoang, Mien V; Smith, Lois E H; Senger, Donald R

    2011-04-01

    In ischemic retinopathies, underlying hypoxia drives abnormal neovascularization that damages retina and causes blindness. The abnormal neovasculature is tortuous and leaky and fails to alleviate hypoxia, resulting in more pathological neovascularization and retinal damage. With an established model of ischemic retinopathy we found that calpain inhibitors, when administered in moderation, reduced architectural abnormalities, reduced vascular leakage, and most importantly reduced retinal hypoxia. Mechanistically, these calpain inhibitors improved stability and organization of the actin cytoskeleton in retinal endothelial cells undergoing capillary morphogenesis in vitro, and they similarly improved organization of actin cables within new blood vessels in vivo. Hypoxia induced calpain activity in retinal endothelial cells and severely disrupted the actin cytoskeleton, whereas calpain inhibitors preserved actin cables under hypoxic conditions. Collectively, these findings support the hypothesis that hyper-activation of calpains by hypoxia contributes to disruption of the retinal endothelial cell cytoskeleton, resulting in formation of neovessels that are defective both architecturally and functionally. Modest suppression of calpain activity with calpain inhibitors restores cytoskeletal architecture and promotes formation of a functional neovasculature, thereby reducing underlying hypoxia. In sharp contrast to "anti-angiogenesis" strategies that cannot restore normoxia and may aggravate hypoxia, the therapeutic strategy described here does not inhibit neovascularization. Instead, by improving the function of neovascularization to reduce underlying hypoxia, moderate calpain inhibition offers a method for alleviating retinal ischemia, thereby suggesting a new treatment paradigm based on improvement rather than inhibition of new blood vessel growth.

  10. Retinal Remodeling And Metabolic Alterations in Human AMD

    Directory of Open Access Journals (Sweden)

    Bryan William Jones

    2016-04-01

    Full Text Available Age-related macular degeneration (AMD is a progressive retinal degeneration resulting in central visual field loss, ultimately causing debilitating blindness. AMD affects 18% of Americans from 65 to 74, 30% older than 74 years of age and is the leading cause of severe vision loss and blindness in Western populations. While many genetic and environmental risk factors are known for AMD, we currently know less about the mechanisms mediating disease progression.The pathways and mechanisms through which genetic and non-genetic risk factors modulate development of AMD pathogenesis remain largely unexplored. Moreover, current treatment for AMD is palliative and limited to wet/exudative forms. Retina is a complex, heterocellular tissue and most retinal cell classes are impacted or altered in AMD. Defining disease and stage-specific cytoarchitectural and metabolic responses in AMD is critical for highlighting targets for intervention. The goal of this paper is to illustrate cell types impacted in AMD and demonstrate the implications of those changes, likely beginning in the retinal pigment epithelium (RPE, for remodeling of the the neural retina.Tracking heterocellular responses in disease progression is best achieved with computational molecular phenotyping (CMP, a tool that enables acquisition of a small molecule fingerprint for every cell in the retina. CMP uncovered critical cellular and molecular pathologies (remodeling and reprogramming in progressive retinal degenerations such as retinitis pigmentosa (RP. We now applied these approaches to normal human and AMD tissues mapping progression of cellular and molecular changes in AMD retinas, including late-stage forms of the disease.Major findings: 1 Evidence of metabolic instability in RPE in dry-AMD.2 Photoreceptors show clear indications of stress prior to cell death.3 Cone opsin processing by the RPE in AMD retinas may be differentially compromised vs. rod opsin.4 Müller cells in AMD exhibit

  11. AMD--the retinal disease with an unprecised etiopathogenesis: in search of effective therapeutics.

    Science.gov (United States)

    Nowak, Jerzy Z

    2014-01-01

    AMD (age-related macular degeneration) is a progressive vision-threatening ocular disease, affecting central region of the retina--the macula--and manifesting in the elderly. AMD is a degenerative disease, and the degeneration affects primarily the retinal pigment epithelial (RPE) cells and secondarily the photoreceptors, leading consequently to disturbances or partial loss of central vision and legal blindness. Clinically, the disease is classified as: atrophic--dry AMD (in majority of cases), and neovascular--wet AMD (with choroidal neovascularization--CNV: 10-15% of all AMD cases). Pathogenesis of AMD is complex, multifactorial and only poorly recognized. Main risk factors include: advanced age, genetic predispositions, environmental determinants, history of exposure to intensive light and smoking. At least four molecular processes contribute to the development of AMD pathology: lipofuscinogenesis, drusogenesis, inflammation and choroidal neovascularization (in wet AMD). Since vascular endothelial growth factor (VEGF) is a predominant proangiogenic factor in CNV. the wet AMD can be treated with intravitreous application of "anti-VEGF" agents (Avastin, Lucentis, Eylea). Till now, there is no approved therapy for dry AMD, although several agents/treatments are currently in clinical trials. This paper briefly describes major molecular and cellular events leading to AMD, and presents currently used and new experimental therapeutic strategies against AMD.

  12. Modulation of retinal image vasculature analysis to extend utility and provide secondary value from optical coherence tomography imaging.

    Science.gov (United States)

    Cameron, James R; Ballerini, Lucia; Langan, Clare; Warren, Claire; Denholm, Nicholas; Smart, Katie; MacGillivray, Thomas J

    2016-04-01

    Retinal image analysis is emerging as a key source of biomarkers of chronic systemic conditions affecting the cardiovascular system and brain. The rapid development and increasing diversity of commercial retinal imaging systems present a challenge to image analysis software providers. In addition, clinicians are looking to extract maximum value from the clinical imaging taking place. We describe how existing and well-established retinal vasculature segmentation and measurement software for fundus camera images has been modulated to analyze scanning laser ophthalmoscope retinal images generated by the dual-modality Heidelberg SPECTRALIS(®) instrument, which also features optical coherence tomography.

  13. Expression of angiopoietin-2 and vascular endothelial growth factor receptor-3 correlates with lymphangiogenesis and angiogenesis and affects survival of oral squamous cell carcinoma.

    Directory of Open Access Journals (Sweden)

    Chao Li

    Full Text Available BACKGROUND: Both Ang-2 and VEGFR-3 are major regulators of angiogenesis and lymphangiogenesis, respectively, and thus may affect prognosis of OSCC. We sought to determine the associations between Ang-2 and VEGFR-3 expression and survival of OSCC. METHODS: Ang-2 and VEGFR-3 expression was determined immunohistochemically in tumor tissues from 112 patients with OSCC; OSCC-adjacent noncancerous oral tissue from 85 OSCC patients; and normal oral mucosa from 37 cancer-free individuals. A log-rank test and Cox proportional hazard models were used to compare survival among different groups with expression of Ang-2 and VEGFR-3. RESULTS: Ang-2 and VEGFR-3 expression was upregulated in OSCC compared to nontumor tissue (all P<0.05. High Ang-2 expression positively correlated with microvessel density (MVD (P<0.01, and high VEGFR-3 expression positively correlated with lymph node metastasis (P<0.01 and lymphatic vessel density (LVD (P<0.01. The patients with high expression of Ang-2 alone or in combination with VEGFR-3 had a significantly worse survival than in patients with low expression of Ang-2 or any other co-expression status (all P<0.05, respectively. Furthermore, multivariable analysis showed that patients with high expression of Ang-2 alone or in combination with VEGFR-3 had a significantly increased risk of death compared with those with low expression of Ang-2 or any other co-expression status (HR, 2.7, 95% CI, 1.1-6.2 and 5.0, 1.3-15.4, respectively. CONCLUSIONS: These results suggest that increased expression in tumors of Ang-2 may individually, or in combination with VEGFR-3, predict poor prognosis of OSCC.

  14. The Role of Nitric Oxide in Modulating Retinal, Choroidal, and Anterior Uveal Blood Flows in the Domestic Piglet

    Science.gov (United States)

    1993-11-17

    soluble guanylate cyclase (sGe) and promote the conversion of GTP to cGMP which leads to relaxation of the vascular smooth muscle cell. Physical ...inner nuclear layer of the retina. with a speclftC and consistent distribution in a wide variety of mammals (Sandell, 1985). The functional...high-tension glaucoma ( Luscher , 1991 ; Gasser & Flammer, 1991). Failure of regulatory vascular reacttvlty is an Important component of many retinal

  15. Branch Retinal Artery Occlusion Caused by Toxoplasmosis in an Adolescent

    Directory of Open Access Journals (Sweden)

    Elizabeth Chiang

    2012-10-01

    Full Text Available Purpose: Branch retinal artery occlusion (BRAO, while not uncommon in elderly patient populations, is rare in children and adolescents. We report a case of a BRAO secondary to toxoplasmosis in this demographic. Case: A previously healthy 17-year-old male developed a unilateral BRAO in conjunction with inflammation and increased intraocular pressure. Family history was positive for cerebrovascular accidents in multiple family members at relatively young ages. The patient had a hypercoagulable workup as well as a cardiovascular workup which were both normal. A rheumatologic workup was unremarkable. By 3 weeks, a patch of retinitis was more easily distinguished from the BRAO and the diagnosis of ocular toxoplasmosis was made. Treatment was started with prednisone and azithromycin with subsequent improvement in vision. Toxoplasma antibody levels were elevated for IgG and negative for IgM, IgA, and IgE. The etiology of the BRAO was attributed to ocular toxoplasmosis. Conclusions: Vascular occlusions are rare in toxoplasmosis. This is the third case report of a BRAO in a patient in the pediatric population. The diagnosis of ocular toxoplasmosis should be considered in young patients with retinal artery occlusions associated with inflammation.

  16. Central retinal vein occlusion: A patient with systemic sclerosis

    Directory of Open Access Journals (Sweden)

    Karadžić Jelena

    2016-01-01

    Full Text Available Introduction. Scleroderma (systemic sclerosis is a severe chronic connective tissue disease, which results in involvement of numerous internal organs. Changes in the eye are the consequences of organ-specific manifestations of scleroderma or adverse effects of immunosuppressive treatment applied. Case report. We reported a 42-year-old woman with systemic sclerosis and acute deterioration of vision in the left eye, with visual acuity 0.9. After thorough clinical examination, including fluorescein angiography and optical coherence tomography, the diagnosis of nonischemic central retinal vein occlusion was made. Further biochemical, rheumatological and immunological investigation, apart from inactive systemic sclerosis, showed normal findings. Therefore, the cause of central retinal vein occlusion could only be attributed to the microvascular changes in systemic sclerosis. After three months, visual acuity deteriorated to 0.6 due to the development of cystoid macular edema. The patient received intravitreal injection of bevacizumab and after a single dose visual acuity improved to 0.9. After a 6- month follow-up, macular edema resolved and visual acuity stabilized. Conclusion. According to our knowledge and current data from the literature, central retinal vein occlusion is a rare vision threatening manifestation of scleroderma. There are only few published case reports on central vein occlusion in scleroderma patients. Examination of the ocular fundus is recommended for evaluation of vascular disease in patients with systemic sclerosis.

  17. [Congenital retinal folds in different clinical cases].

    Science.gov (United States)

    Munteanu, M

    2005-01-01

    We present 12 clinical cases of congenital retinal folds with different etiologies: posterior primitive vitreous persistency and hyperplasia (7 cases),retinocytoma (1 case). retinopathy of prematurity (1 case), astrocytoma of the retina (1 case), retinal vasculitis (1 case), Goldmann-Favre syndrome (1 case). Etiopathogenic and nosological aspects are discussed; the congenital retinal folds are interpreted as a symptom in a context of a congenital or acquired vitreo-retinal pathology.

  18. Automated detection of retinal whitening in malarial retinopathy

    Science.gov (United States)

    Joshi, V.; Agurto, C.; Barriga, S.; Nemeth, S.; Soliz, P.; MacCormick, I.; Taylor, T.; Lewallen, S.; Harding, S.

    2016-03-01

    Cerebral malaria (CM) is a severe neurological complication associated with malarial infection. Malaria affects approximately 200 million people worldwide, and claims 600,000 lives annually, 75% of whom are African children under five years of age. Because most of these mortalities are caused by the high incidence of CM misdiagnosis, there is a need for an accurate diagnostic to confirm the presence of CM. The retinal lesions associated with malarial retinopathy (MR) such as retinal whitening, vessel discoloration, and hemorrhages, are highly specific to CM, and their detection can improve the accuracy of CM diagnosis. This paper will focus on development of an automated method for the detection of retinal whitening which is a unique sign of MR that manifests due to retinal ischemia resulting from CM. We propose to detect the whitening region in retinal color images based on multiple color and textural features. First, we preprocess the image using color and textural features of the CMYK and CIE-XYZ color spaces to minimize camera reflex. Next, we utilize color features of the HSL, CMYK, and CIE-XYZ channels, along with the structural features of difference of Gaussians. A watershed segmentation algorithm is used to assign each image region a probability of being inside the whitening, based on extracted features. The algorithm was applied to a dataset of 54 images (40 with whitening and 14 controls) that resulted in an image-based (binary) classification with an AUC of 0.80. This provides 88% sensitivity at a specificity of 65%. For a clinical application that requires a high specificity setting, the algorithm can be tuned to a specificity of 89% at a sensitivity of 82%. This is the first published method for retinal whitening detection and combining it with the detection methods for vessel discoloration and hemorrhages can further improve the detection accuracy for malarial retinopathy.

  19. Choroidal melanoma clinically simulating a retinal angioma

    Energy Technology Data Exchange (ETDEWEB)

    Shields, J.A.; Joffe, L.; Guibor, P.

    1978-01-01

    An amelanotic fundus lesion in a 35-year-old man was associated with a dilated retinal vessel, thus suggesting the diagnosis of retinal angioma. Fluorescein angiography and B-scan ultrasonography were not diagnostic, but a radioactive phosphorus uptake test suggested the lesion was malignant. The enucleated globe showed a malignant choroidal melanoma drained by a large retinal vein.

  20. Choroidal melanoma clinically simulating a retinal angioma.

    Science.gov (United States)

    Shields, J A; Joffe, L; Guibor, P

    1978-01-01

    An amelanotic fundus lesion in a 35-year-old man was associated with a dilated retinal vessel, thus suggesting the diagnosis of retinal angioma. Fluorescein angiography and B-scan ultrasonography were not diagnostic, but a radioactive phosphorus uptake test suggested the lesion was malignant. The enucleated globe showed a malignant choroidal melanoma drained by a large retinal vein.

  1. CD34 Promotes Pathological Epi-Retinal Neovascularization in a Mouse Model of Oxygen-Induced Retinopathy.

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    Martin J Siemerink

    Full Text Available The sialomucins CD34 and podocalyxin (PODXL are anti-adhesive molecules expressed at the luminal membrane of endothelial cells of small blood vessels and facilitate vascular lumen formation in the developing mouse aorta. CD34 transcript and protein levels are increased during human angiogenesis, its expression is particularly enriched on endothelial tip cell filopodia and CD34 is a marker for tip cells in vitro. Here, we investigated whether CD34 merely marks endothelial tip cells or has a functional role in tip cells and angiogenesis. We assessed that silencing CD34 in human microvascular endothelial cells has little effect on endothelial cell migration or invasion, but has a significant effect on vascular-endothelial growth factor-induced angiogenic sprouting activity in vitro. In vivo, the absence of CD34 reduced the density of filopodia on retinal endothelial tip cells in neonatal mice, but did not influence the overall architecture of the retinal vascular network. In oxygen-induced retinopathy, Cd34-/- mice showed normal intra-retinal regenerative angiogenesis but the number of pathological epi-retinal neovascular tufts were reduced. We conclude that CD34 is not essential for developmental vascularization in the retina, but its expression promotes the formation of pathological, invasive vessels during neovascularization.

  2. CD34 Promotes Pathological Epi-Retinal Neovascularization in a Mouse Model of Oxygen-Induced Retinopathy

    Science.gov (United States)

    Siemerink, Martin J.; Dallinga, Marchien G.; Gora, Tomek; Cait, Jessica; Vogels, Ilse M. C.; Yetin-Arik, Bahar; Van Noorden, Cornelis J. F.; Klaassen, Ingeborg; McNagny, Kelly M.; Schlingemann, Reinier O.

    2016-01-01

    The sialomucins CD34 and podocalyxin (PODXL) are anti-adhesive molecules expressed at the luminal membrane of endothelial cells of small blood vessels and facilitate vascular lumen formation in the developing mouse aorta. CD34 transcript and protein levels are increased during human angiogenesis, its expression is particularly enriched on endothelial tip cell filopodia and CD34 is a marker for tip cells in vitro. Here, we investigated whether CD34 merely marks endothelial tip cells or has a functional role in tip cells and angiogenesis. We assessed that silencing CD34 in human microvascular endothelial cells has little effect on endothelial cell migration or invasion, but has a significant effect on vascular-endothelial growth factor-induced angiogenic sprouting activity in vitro. In vivo, the absence of CD34 reduced the density of filopodia on retinal endothelial tip cells in neonatal mice, but did not influence the overall architecture of the retinal vascular network. In oxygen-induced retinopathy, Cd34-/- mice showed normal intra-retinal regenerative angiogenesis but the number of pathological epi-retinal neovascular tufts were reduced. We conclude that CD34 is not essential for developmental vascularization in the retina, but its expression promotes the formation of pathological, invasive vessels during neovascularization. PMID:27352134

  3. Exploring the retinal connectome

    Science.gov (United States)

    Anderson, James R.; Jones, Bryan W.; Watt, Carl B.; Shaw, Margaret V.; Yang, Jia-Hui; DeMill, David; Lauritzen, James S.; Lin, Yanhua; Rapp, Kevin D.; Mastronarde, David; Koshevoy, Pavel; Grimm, Bradley; Tasdizen, Tolga; Whitaker, Ross

    2011-01-01

    Purpose A connectome is a comprehensive description of synaptic connectivity for a neural domain. Our goal was to produce a connectome data set for the inner plexiform layer of the mammalian retina. This paper describes our first retinal connectome, validates the method, and provides key initial findings. Methods We acquired and assembled a 16.5 terabyte connectome data set RC1 for the rabbit retina at ≈2 nm resolution using automated transmission electron microscope imaging, automated mosaicking, and automated volume registration. RC1 represents a column of tissue 0.25 mm in diameter, spanning the inner nuclear, inner plexiform, and ganglion cell layers. To enhance ultrastructural tracing, we included molecular markers for 4-aminobutyrate (GABA), glutamate, glycine, taurine, glutamine, and the in vivo activity marker, 1-amino-4-guanidobutane. This enabled us to distinguish GABAergic and glycinergic amacrine cells; to identify ON bipolar cells coupled to glycinergic cells; and to discriminate different kinds of bipolar, amacrine, and ganglion cells based on their molecular signatures and activity. The data set was explored and annotated with Viking, our multiuser navigation tool. Annotations were exported to additional applications to render cells, visualize network graphs, and query the database. Results Exploration of RC1 showed that the 2 nm resolution readily recapitulated well known connections and revealed several new features of retinal organization: (1) The well known AII amacrine cell pathway displayed more complexity than previously reported, with no less than 17 distinct signaling modes, including ribbon synapse inputs from OFF bipolar cells, wide-field ON cone bipolar cells and rod bipolar cells, and extensive input from cone-pathway amacrine cells. (2) The axons of most cone bipolar cells formed a distinct signal integration compartment, with ON cone bipolar cell axonal synapses targeting diverse cell types. Both ON and OFF bipolar cells receive

  4. Vasodilator effects of adenosine on retinal arterioles in streptozotocin-induced diabetic rats.

    Science.gov (United States)

    Nakazawa, Taisuke; Mori, Asami; Saito, Maki; Sakamoto, Kenji; Nakahara, Tsutomu; Ishii, Kunio

    2008-02-01

    Adenosine is a potent vasodilator of retinal blood vessels and is implicated to be a major regulator of retinal blood flow during metabolic stress, but little is known about the impact of diabetes on the role of adenosine in regulation of retinal hemodynamics. Therefore, we examined how diabetes affects adenosine-induced vasodilation of retinal arterioles. Male Wistar rats were treated with streptozotocin (80 mg/kg, intraperitoneally), and experiments were performed 6-8 weeks later. Rats were treated with tetrodotoxin (50 microg/kg, intravenously [i.v.]) to eliminate any nerve activity and prevent movement of the eye and infused with methoxamine continuously to maintain adequate systemic circulation. Fundus images were captured with a digital camera that was equipped with a special objective lens, and diameters of retinal arterioles were measured. Adenosine increased diameters of retinal arterioles and decreased systemic blood pressure. These responses were significantly attenuated by the nitric oxide synthase inhibitor N(G)-nitro-L-arginine methyl ester (30 mg/kg, i.v.) and the adenosine triphosphate-dependent K+ (K(ATP)) channel blocker glibenclamide (20 mg/kg, i.v.). The depressor responses to adenosine were reduced in diabetic rats, whereas diabetes did not alter vasodilation of retinal arterioles to adenosine. In contrast, both depressor response and vasodilation of retinal arteriole to acetylcholine were reduced in diabetic rats. The retinal vasodilator responses to adenosine and acetylcholine observed in diabetic rats were diminished by N(G)-nitro-L-arginine methyl ester. There were no differences in the responses to pinacidil, a K(ATP) channel opener, between the diabetic and nondiabetic rats. These results suggest that both the activation of nitric oxide synthase and opening of K(ATP) channels contribute to the vasodilator effects of adenosine in rats in vivo. However, diabetes has no significant impact on the vasodilation mediated by these mechanisms in

  5. Retinal β-ionone ring-salinixanthin interactions in xanthorhodopsin: a study using artificial pigments.

    Science.gov (United States)

    Smolensky Koganov, Elena; Hirshfeld, Amiram; Sheves, Mordechai

    2013-02-19

    Xanthorhodopsin (xR) is a retinal protein that contains, in addition to the retinal chromophore, a carotenoid (salinixanthin) that functions as a light-harvesting antenna [Balashov, S. P., et al. (2005) Science 309, 2061-2064]. The center-center distance between the two polyene chains is 12-13 Å, but the distance between the two rings of retinal and salinixanthin is surprisingly small (~5 Å) with an angle of ~45° [Luecke, H., et al. (2008) Proc. Natl. Acad. Sci. U.S.A. 105, 16561-16565]. We aimed to clarify the role of the β-ionone ring in the binding of retinal to apo-xR, as well as a possible role that the β-ionone ring plays in fixation of the salinixanthin 4-keto ring. The binding of native retinal and series of synthetic retinal analogues modified in the β-ionone ring to apo-xR was monitored by absorption and circular dichroism (CD) spectroscopies. The results indicate that the β-ionone ring modification significantly affected formation of the retinal-protein covalent bond as well as the pigment absorption and CD spectra. It was observed that several retinal analogues, modified in the retinal β-ionone ring, did not bind to apo-xR and did not form the pigment. Also, none of these analogues induced the fixation of the salinixanthin 4-keto ring. In addition, we show that the native retinal within its binding site adopts exclusively the 6-s-trans ring-chain conformation.

  6. [Therapy of fundus oculi vascular pathology by solcoseryl].

    Science.gov (United States)

    Eliseeva, E G; Vorob'eva, O K; Astaf'eva, N V

    1999-01-01

    Long (for more than 17 years) therapy of 2331 patients (3122 eyes) with vascular conditions of the fundus oculi by a retinotropic drug solcoseryl showed its high efficacy as a monotherapy and in complex with other traditional and symptomatic treatments. Solcoseryl improved the visual function and hemodynamics of retinal vessels, promoted a more stable and longer stabilization of the treatment results, and accelerated the rehabilitation of patients.

  7. Mitochondrial transcription factor A (Tfam) gene sequencing and mitochondrial evaluation in inherited retinal dysplasia in miniature schnauzer dogs

    OpenAIRE

    Bauer, Bianca S.; Forsyth, George W.; Sandmeyer, Lynne S.; Grahn, Bruce H.

    2011-01-01

    Mitochondrial transcription factor A (Tfam) has been implicated in the pathogenesis of retinal dysplasia in miniature schnauzer dogs and it has been proposed that affected dogs have altered mitochondrial numbers, size, and morphology. To test these hypotheses the Tfam gene of affected and normal miniature schnauzer dogs with retinal dysplasia was sequenced and lymphocyte mitochondria were quantified, measured, and the morphology was compared in normal and affected dogs using transmission elec...

  8. Fractal analysis of the retinal vasculature and chronic kidney disease.

    Science.gov (United States)

    Sng, Chelvin C A; Sabanayagam, Charumathi; Lamoureux, Ecosse L; Liu, Erica; Lim, Su Chi; Hamzah, Haslina; Lee, Jeannette; Tai, E Shyong; Wong, Tien Y

    2010-07-01

    BACKGROUND. Fractal analysis provides a global index of the geometric complexity and optimality of vascular networks. In this study, we investigated the relationship between fractal measurements of the retinal vasculature and chronic kidney disease (CKD). METHODS. This was a population-based case-control study which included participants from the Singapore Prospective Study Program. We identified 261 participants with CKD, defined as estimated glomerular filtration rate of fractal dimension (D(f)) was quantified from digitized fundus photographs using a computer-based programme. RESULTS. The mean D(f) was 1.43 +/- 0.048 in the participants with CKD and 1.44 +/- 0.042 in controls (P = 0.013). Suboptimal D(f) in the lowest (first) and highest (fifth) quintiles were associated with an increased prevalence of CKD after adjusting for age, systolic blood pressure, diabetes and other risk factors [odds ratio (OR) 2.10, 95% confidence interval (CI) 1.15, 3.83 and OR 1.84, 95% CI 1.06, 3.17; compared to the fourth quintile, respectively). This association was present even in participants without diabetes or hypertension. CONCLUSIONS. Our study found that an abnormal retinal vascular network is associated with an increased risk of CKD, supporting the hypothesis that deviations from optimal microvascular architecture may be related to kidney damage.

  9. Necrotizing Retinitis Secondary to Congenital Cytomegalovirus Infection Associated with Severe Combined Immunodeficiency

    Directory of Open Access Journals (Sweden)

    Pehmen Yasin Ozcan

    2016-01-01

    Full Text Available A 20-day-old male infant who was born at 39 weeks of gestation was admitted to neonatal intensive care unit due to severe respiratory insufficiency. In retinal examination, peripheric retinal white-black color areas that correspond to necrotizing retinitis, moderate vitritis, macular and optic nerve head involvement, vascular leakage, and sheathing indicating perivasculitis were revealed. Despite the fact that CMV specific IgM was undetectable, CMV DNA with high viral load was found in his blood sample by means of real-time polymerase chain reaction assay. Serologic examination (IgM for rubella, toxoplasma, herpes simplex type 2, and human immunodeficiency virus (anti-HIV was negative. During the further evaluation for systemic immune dysfunction, decreased immunoglobulin and lymphocyte levels that confirm the diagnosis of severe combined immunodeficiency have been reached. Although given systemic intravenous ganciclovir and antibiotics treatment, the patient died at the 4th month of life due to respiratory insufficiency.

  10. Necrotizing Retinitis Secondary to Congenital Cytomegalovirus Infection Associated with Severe Combined Immunodeficiency

    Science.gov (United States)

    Celik, Hasan Tolga; Sonmez, Kenan; Celik, Melda

    2016-01-01

    A 20-day-old male infant who was born at 39 weeks of gestation was admitted to neonatal intensive care unit due to severe respiratory insufficiency. In retinal examination, peripheric retinal white-black color areas that correspond to necrotizing retinitis, moderate vitritis, macular and optic nerve head involvement, vascular leakage, and sheathing indicating perivasculitis were revealed. Despite the fact that CMV specific IgM was undetectable, CMV DNA with high viral load was found in his blood sample by means of real-time polymerase chain reaction assay. Serologic examination (IgM) for rubella, toxoplasma, herpes simplex type 2, and human immunodeficiency virus (anti-HIV) was negative. During the further evaluation for systemic immune dysfunction, decreased immunoglobulin and lymphocyte levels that confirm the diagnosis of severe combined immunodeficiency have been reached. Although given systemic intravenous ganciclovir and antibiotics treatment, the patient died at the 4th month of life due to respiratory insufficiency. PMID:27999698

  11. [Study on preferred retinal locus].

    Science.gov (United States)

    Dai, Bing-Fa; Hu, Jian-Min; Xu, Duan-Lian

    2012-03-01

    Preferred retinal locus (PRL) is always found in the age-related macular degeneration and other macular damages in patients with low vision, and it is a very important anatomic position in patients with central vision impairment to achieve the rehabilitation. In recent years, the training of preferred retinal locus (PRL) has become a research hotspot of low vision rehabilitation, it can clearly improve functional vision and quality of life. The authors reviewed relevant literatures, and summarized the definition, position, characteristics, training and clinical implications of the PRL.

  12. Angiographic results of retinal-retinal anastomosis and retinal-choroidal anastomosis after treatments in eyes with retinal angiomatous proliferation

    Directory of Open Access Journals (Sweden)

    Saito M

    2012-08-01

    Full Text Available Masaaki Saito,1 Tomohiro Iida,1,2 Mariko Kano,1 Kanako Itagaki11Department of Ophthalmology, Fukushima Medical University School of Medicine, Fukushima, 2Department of Ophthalmology, Tokyo Women's Medical University School of Medicine, Tokyo, JapanBackground: The purpose of this study was to evaluate the angiographic results of retinal-retinal anastomosis (RRA and retinal-choroidal anastomosis (RCA for eyes with retinal angiomatous proliferation (RAP after treatment with intravitreal bevacizumab injections as monotherapy or intravitreal bevacizumab combined with photodynamic therapy.Methods: In this interventional, consecutive case series, we retrospectively reviewed five naïve eyes from four patients (mean age 80 years treated with three consecutive monthly intravitreal bevacizumab (1.25 mg/0.05 mL injections as initial treatment, and followed up for at least 3 months. In cases with over 3 months of follow-up and having recurrence of RAP or leakage by fluorescein angiography, retreatment was performed with a single intravitreal bevacizumab injection and photodynamic therapy.Results: Indocyanine green angiography showed RRA in three eyes with subretinal neovascularization and RCA in two eyes with choroidal neovascularization at baseline. At 3 months after baseline (month 3, neither the RRA nor RCA was occluded in any eye on indocyanine green angiography. Retreatment with intravitreal bevacizumab plus photodynamic therapy was performed in three eyes at months 3 (persistent leakage on fluorescein angiography, 6, and 7 (recurrence of RAP lesion, which achieved obvious occlusion of the RRA and RCA. Mean best-corrected visual acuity improved from 0.13 to 0.21 at month 3 (P = 0.066. No complications or systemic adverse events were noted.Conclusion: Although intravitreal bevacizumab for RAP was effective in improving visual acuity during short-term follow-up, intravitreal bevacizumab could not achieve complete occlusion of RRA and RCA, which could

  13. Spectrophotometric retinal oximetry in pigs

    DEFF Research Database (Denmark)

    Traustason, Sindri; Kiilgaard, Jens Folke; Karlsson, Robert;

    2013-01-01

    , Reykjavik, Iceland). The device simultaneously acquires images at two wavelengths (570 nm and 600 nm) and specialized software automatically detects retinal blood vessels. In three pigs, invasive pO2-measurements were performed after the initial non-invasive measurements. RESULTS: Comparison of femoral...... arterial oxygen saturation and the optical density ratio over retinal arteries revealed an approximately linear relationship (R(2) = 0.74, p = 3.4 x 10(-9)). In order to test the validity of applying the arterial calibration to veins, we compared non-invasive oximetry measurements to invasive pO2...

  14. Imaging of long-term retinal damage after resolved cotton wool spots

    Science.gov (United States)

    Gomez, Maria Laura; Mojana, Francesca; Bartsch, Dirk-Uwe; Freeman, William R.

    2014-01-01

    Purpose Human Immunodeficiency Virus (HIV) patients develop non-infectious retinopathy characterized by retinal cotton wool spots (CWS) and micro vascular abnormalities. Ophthalmoscopically CWS fade with time. We hypothesized that structural changes should be permanent and possibly visible well after ophthalmoscopic resolution. We used simultaneous spectral domain optical coherence tomography/ scanning laser ophthalmoscope (SD-OCT/SLO) to allow co-localization of the lesions and determine the extent and location of residual damage after ophthalmoscopic resolution of the lesions. Design Retrospective, non-interventional case series. Participants Eight eyes of seven human immunodeficiency virus (HIV) patients with nineteen resolved retinal cotton wool spots. Methods Nineteen retinal cotton wool spots were imaged between 2 and 16 (median 7.84) years after the acute lesions using simultaneous SD-OCT and scanning laser ophthalmoscope (SLO) examinations. The areas of the previous CWS were scanned by overlaying the color retinal image over the SLO image and scanning at high resolution in the horizontal plane thru the resolved lesion. Each CWS lesion had a control area taken from the same eye within 2 disc diameters of the lesion. The thickness of each of the retinal layers was compared between lesions and control areas using a paired t-test using multi-test correction. Main Outcome Measures Thickness of the retinal nerve fiber layer (NFL), ganglion cell layer (GCL), inner plexiform layer (IPL), inner nuclear layer (INL), outer plexiform layer (OPL) and outer nuclear (ONL) layers. Results The largest loss of thickness was seen in the retinal GCL with a 43% reduction in thickness. There was a statistically significant thinning of the retinal NFL, GCL, IPL, INL and OPL. The median thickness differences ranged from 5 to 7 microns. This difference was highly statistically significant. Another striking finding was the displacement of the ONL towards the retinal surface

  15. Duplex Color Doppler Evaluation of Retinal Arterial Blood Flow in Type 2 Diabetic Subjects without Retinopathy

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    Mashah Binte Amin

    2014-09-01

    Full Text Available Background: Diabetic retinopathy is a vascular disorder affecting the microvasculature of retina. It is caused by changes in the blood vessels of retina. If untreated, it may lead to blindness which is usually preventable if retinopathy is diagnosed early and treated promptly. In ophthalmology, color Doppler imaging is a new method that enables us to assess the orbital vasculature. It allows for simultaneous two dimensional anatomical and Doppler evaluations of hemodynamic characteristics of retinal artery. Objective: To observe the difference between Doppler flow velocity indices (peak systolic velocity, end diastolic velocity and resistive index of retinal artery in type 2 diabetic subjects without retinopathy and those of normal controls. Materials and Methods: This case-control study was carried out in the department of Radiology and Imaging, Bangladesh Institute of Research and Rehabilitation in Diabetes, Endocrine and Metabolic Disorders (BIRDEM in collaboration with Ophthalmology Outpatient Department, BIRDEM, Dhaka from July 2011 to June 2013. Eighty diabetic patients without retinopathy aged 27–68 years were enrolled as cases and age and sex matched 80 healthy subjects were selected as controls. Type 1 diabetic patients, type 2 diabetics with retinopathy, hypertensive and dyslipidemic subjects were excluded from the study. All the selected subjects underwent duplex Doppler ultrasonography of both eyes using 5 to 7.5 MHZ linear phase transducer. Duplex color Doppler findings including spectral analysis (PSV, EDV and RI were recorded. Unpaired t test was done to compare blood flow velocity indices of retinal artery in type 2 diabetic patients without retinopathy and that of healthy control subjects. p value <0.05 was considered as significant. Results: Majority (42.5% and 47.5% of subjects were in 4th decade of life in both groups with predominance of males. The mean duration of diabetes was 4.56 ± 2.1 years. Mean peak systolic

  16. Retinal pathology of pediatric cerebral malaria in Malawi.

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    Valerie A White

    Full Text Available INTRODUCTION: The causes of coma and death in cerebral malaria remain unknown. Malarial retinopathy has been identified as an important clinical sign in the diagnosis and prognosis of cerebral malaria. As part of a larger autopsy study to determine causes of death in children with coma presenting to hospital in Blantyre, Malawi, who were fully evaluated clinically prior to death, we examined the histopathology of eyes of patients who died and underwent autopsy. METHODOLOGY/PRINCIPAL FINDINGS: Children with coma were admitted to the pediatric research ward, classified according to clinical definitions as having cerebral malaria or another cause of coma, evaluated and treated. The eyes were examined by direct and indirect ophthalmoscopy. If a child died and permission was given, a standardized autopsy was carried out. The patient was then assigned an actual cause of death according to the autopsy findings. The eyes were examined pathologically for hemorrhages, cystoid macular edema, parasite sequestration and thrombi. They were stained immunohistochemically for fibrin and CD61 to identify the components of thrombi, beta-amyloid precursor protein to detect axonal damage, for fibrinogen to identify vascular leakage and for glial fibrillary acidic protein to detect gliosis. Sixty-four eyes from 64 patients were examined: 35 with cerebral malaria and 29 with comas of other causes. Cerebral malaria was distinguished by sequestration of parasitized erythrocytes, the presence and severity of retinal hemorrhages, the presence of cystoid macular edema, the occurrence and number of fibrin-platelet thrombi, the presence and amount of axonal damage and vascular leakage. CONCLUSIONS/SIGNIFICANCE: We found significant differences in retinal histopathology between patients who died of cerebral malaria and those with other diagnoses. These histopathological findings offer insights into the etiology of malarial retinopathy and provide a pathological basis for

  17. Quantitative genetic analysis of retinal degeneration in the blind cavefish Astyanax mexicanus.

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    Kelly E O'Quin

    Full Text Available The retina is the light-sensitive tissue of the eye that facilitates vision. Mutations within genes affecting eye development and retinal function cause a host of degenerative visual diseases, including retinitis pigmentosa and anophthalmia/microphthalmia. The characin fish Astyanax mexicanus includes both eyed (surface fish and eyeless (cavefish morphs that initially develop eyes with normal retina; however, early in development, the eyes of cavefish degenerate. Since both surface and cave morphs are members of the same species, they serve as excellent evolutionary mutant models with which to identify genes causing retinal degeneration. In this study, we crossed the eyed and eyeless forms of A. mexicanus and quantified the thickness of individual retinal layers among 115 F(2 hybrid progeny. We used next generation sequencing (RAD-seq and microsatellite mapping to construct a dense genetic map of the Astyanax genome, scan for quantitative trait loci (QTL affecting retinal thickness, and identify candidate genes within these QTL regions. The map we constructed for Astyanax includes nearly 700 markers assembled into 25 linkage groups. Based on our scans with this map, we identified four QTL, one each associated with the thickness of the ganglion, inner nuclear, outer plexiform, and outer nuclear layers of the retina. For all but one QTL, cavefish alleles resulted in a clear reduction in the thickness of the affected layer. Comparative mapping of genetic markers within each QTL revealed that each QTL corresponds to an approximately 35 Mb region of the zebrafish genome. Within each region, we identified several candidate genes associated with the function of each affected retinal layer. Our study is the first to examine Astyanax retinal degeneration in the context of QTL mapping. The regions we identify serve as a starting point for future studies on the genetics of retinal degeneration and eye disease using the evolutionary mutant model Astyanax.

  18. Slit2基因转染对人视网膜色素上皮细胞VEGF表达的影响及其作用机制%Effect of Slit2 gene transfection on vascular endothelial growth factor in retinal pigment epithelium cells and its mechanism

    Institute of Scientific and Technical Information of China (English)

    梅雨; 周希瑗

    2014-01-01

    目的:研究Slit2基因对人视网膜色素上皮(retinal pigment epithelium,RPE)细胞表达血管内皮生长因子(vascular endothelial growth factor,VEGF)的影响,并探讨丝裂原激活(mitogen-activated,MEK)/细胞外信号调节蛋白激酶(extracellular signal regulated protein kinase,ERK)和磷脂酰肌醇-3激酶(phosphatidylinositol 3-kinase,PI3K)/丝氨酸苏氨酸蛋白激酶(serine-threonine kinase,AKT)这2条信号通路在此过程中的作用.方法:(1)体外培养人RPE细胞株RPE-19; (2)将腺病毒介导的Slit2(adenovirus-mediated Slit2,Ad-Slit2)转染RPE细胞,培养12、24 h及48 h;(3)转染前将MEK信号通路阻断剂PD98059、PI3K 信号通路阻断剂LY294002预处理RPE细胞1 h;(4)用real-time PCR及酶联免疫吸附试验(enzyme linked immunosorbent assay,ELISA)检测VEGF的表达水平,用Western blot检测磷酸化ERK、磷酸化AKT的表达情况.结果:Slit2转染的RPE细胞后,real-time PCR结果显示不同时间之间VEGF mRNA表达有差别(F=12.789,P=0.018),组别和时间之间存在交互作用(F=13.375,P=0.017),不同组别有差别(F=16.855,P=0.015),在24 h与48 h,Ad-Slit2组高于空腺病毒组(P4 h=0.002,P48 h=0.018).ELISA结果显示不同时间之间VEGF蛋白表达有差别(F=24.886,P=0.000),组别和时间之间存在交互作用(F=23.524,P=0.000),不同组别有差别(F=28.250,P=0.006),在48 h,Ad-Slit2组高于空腺病毒组(P=0.003).Western blot结果可见p-ERK及p-AKT的蛋白表达水平增加,阻断剂PD98059及LY294002分别能降低ERK、AKT的磷酸化水平,并与Ad-Slit2组相比较,real-time PCR结果显示VEGF mRNA表达水平在不同时间有差别(F=32.202,P=0.000),组别和时间之间存在交互作用(F=8.372,P=0.006);不同组别存在差别(F=15.062,P=0.001),ELISA结果显示VEGF蛋白表达水平在不同时间之间有差别(F=90.703,P=0.000),组别和时间之间存在交互作用(F=4.968,P=0.005),不同组别存在差别(F=69.636,P=0.000).结论:PI3K/AKT以及MEK/ERK这

  19. 音猬因子信号通路在缺氧诱导的人视网膜色素上皮细胞中血管内皮生长因子表达中的作用%Role of Shh signal transduction pathway in vascular endothelial growth factor expression under hypoxia in cultured human retinal pigment epithelial cells

    Institute of Scientific and Technical Information of China (English)

    侯亚南; 雷宁玉; 宋斌; 王丽君

    2016-01-01

    目的 观察探讨音猬因子(Shh)信号转导通路在缺氧诱导的人视网膜色素上皮(hRPE)细胞血管内皮生长因子(VEGF)表达中的作用.方法 hRPE-19细胞分为正常对照组(Cont组)、缺氧组.缺氧组加入100μmol/L CoCl2再分为缺氧对照组(CoCl2组)、cyclopamine处理组(CYA组)、二甲基亚砜对照组(DMSO组).CYA组于造成缺氧前1h加入20μmol/L的cyclopamine进行预处理;DMSO组加入1‰DMSO.各组细胞培养4、8、12、24 h.采用荧光定量PCR(RT-PCR)检测细胞内Shh、VEGF mRNA的表达;酶联免疫吸附测定试验(ELISA)检测细胞培养上清液中VEGF蛋白含量.结果 RT-PCT检测结果显示,缺氧刺激4、8、12、24 h,缺氧组细胞内Shh、VEGF mRNA表达逐渐增高,与Cont组细胞内Shh(F=45.260)、VEGF mRNA(F=264.938)表达比较,差异有统计学意义(P=0.001).CYA组细胞内Shh、VEGF mRNA表达与CoCl2组比较,差异均有统计学意义(P<0.01);DMSO组细胞内Shh、VEGF mRNA表达与CoCl2组比较,差异均无统计学意义(P>0.05).ELISA检测结果显示,CoCl2组细胞培养上清液中VEGF蛋白含量与Cont组比较,差异有统计学意义(F=3 156.676,P=0.001).CYA组细胞培养上清液中VEGF蛋白含量较CoCl2组明显降低,差异均有统计学意义(P<0.01).结论 Shh信号转导通路可能参与了缺氧引起的hRPE细胞中VEGF的表达.%Objective To investigate the role of sonic hedgehog (Shh) signal transduction pathway in the expression of vascular endothelial growth factor (VEGF) under hypoxia in cultured human retinal pigment epithelial (hRPE) cells.Methods ARPE-19 were cultured and divided into normal ARPE-19 (Cont) and hypoxia group (100 μmol/L CoCl2 Cobalt Chloride +-ARPE-19);hypoxia group was further divided into CoCl2 group,cyclopamine group (CYA) and dimethyl sulfoxide (DMSO) group.20 μmol/L cyclopamine was added to the CYA group 1 hour before hypoxia,1‰ DMSO was added into DMSO group at the same time.The hRPE cells were cultured under hypoxia

  20. Protection of retinal ganglion cells and retinal vasculature by Lycium barbarum polysaccharides in a mouse model of acute ocular hypertension.

    Directory of Open Access Journals (Sweden)

    Xue-Song Mi

    Full Text Available Acute ocular hypertension (AOH is a condition found in acute glaucoma. The purpose of this study is to investigate the protective effect of Lycium barbarum polysaccharides (LBP and its protective mechanisms in the AOH insult. LBP has been shown to exhibit neuroprotective effect in the chronic ocular hypertension (COH experiments. AOH mouse model was induced in unilateral eye for one hour by introducing 90 mmHg ocular pressure. The animal was fed with LBP solution (1 mg/kg or vehicle daily from 7 days before the AOH insult till sacrifice at either day 4 or day 7 post insult. The neuroprotective effects of LBP on retinal ganglion cells (RGCs and blood-retinal-barrier (BRB were evaluated. In control AOH retina, loss of RGCs, thinning of IRL thickness, increased IgG leakage, broken tight junctions, and decreased density of retinal blood vessels were observed. However, in LBP-treated AOH retina, there was less loss of RGCs with thinning of IRL thickness, IgG leakage, more continued structure of tight junctions associated with higher level of occludin protein and the recovery of the blood vessel density when compared with vehicle-treated AOH retina. Moreover, we found that LBP provides neuroprotection by down-regulating RAGE, ET-1, Aβ and AGE in the retina, as well as their related signaling pathways, which was related to inhibiting vascular damages and the neuronal degeneration in AOH insults. The present study suggests that LBP could prevent damage to RGCs from AOH-induced ischemic injury; furthermore, through its effects on blood vessel protection, LBP would also be a potential treatment for vascular-related retinopathy.

  1. Role of endoplasmic reticulum stress in the loss of retinal ganglion cells in diabetic retinopathy

    Institute of Scientific and Technical Information of China (English)

    Liping Yang; Lemeng Wu; Dongmei Wang; Ying Li; Hongliang Dou; Mark OMTso; Zhizhong Ma

    2013-01-01

    Endoplasmic reticulum stress is closely involved in the early stage of diabetic retinopathy. In the present study, a streptozotocin-induced diabetic animal model was given an intraperitoneal injection of tauroursodeoxycholic acid. Results from immunofluorescent co-localization experiments showed that both caspase-12 protein and c-Jun N-terminal kinase 1 phosphorylation levels significantly in-creased, which was associated with retinal ganglion celldeath in diabetic retinas. The C/ERB ho-mologous protein pathway directly contributed to glial reactivity, and was subsequently responsible for neuronal loss and vascular abnormalities in diabetic retinopathy. Our experimental findings in-dicate that endoplasmic reticulum stress plays an important role in diabetes-induced retinal neu-ronal loss and vascular abnormalities, and that inhibiting the activation of the endoplasmic reticulum stress pathway provides effective protection against diabetic retinopathy.

  2. Central Retinal Artery Occlusion in a Patient with Metabolic Syndrome X

    Directory of Open Access Journals (Sweden)

    Sonja Predrag Cekić

    2010-01-01

    Full Text Available Purpose: To report a case of central retinal artery occlusion (CRAO in a patient with metabolic syndrome X. Case Report: A 64 year-old-man presented with abrupt, painless, and severe loss of vision in his left eye. Indirect ophthalmoscopy disclosed signs compatible with CRAO and laboratory investigations revealed erythrocyte sedimentation rate of 74 mm/h, C-reactive protein (CRP level of 21 mg/l, hyperglycemia, hyperuricemia, hypertriglyceridemia and hypercholesterolemia. Fluorescein angiography and immunological studies excluded other systemic disorders. The patient met the full criteria of the National Cholesterol Education Program for metabolic syndrome X. Conclusion: In addition to different vascular complications such as stroke, and cardiovascular disease, metabolic syndrome X may be associated with retinal vascular occlusions.

  3. Blood pressure modifies retinal susceptibility to intraocular pressure elevation.

    Directory of Open Access Journals (Sweden)

    Zheng He

    Full Text Available Primary open angle glaucoma affects more than 67 million people. Elevated intraocular pressure (IOP is a risk factor for glaucoma and may reduce nutrient availability by decreasing ocular perfusion pressure (OPP. An interaction between arterial blood pressure and IOP determines OPP; but the exact contribution that these factors have for retinal function is not fully understood. Here we sought to determine how acute modifications of arterial pressure will affect the susceptibility of neuronal function and blood flow to IOP challenge. Anaesthetized (ketamine:xylazine Long-Evan rats with low (∼60 mmHg, sodium nitroprusside infusion, moderate (∼100 mmHg, saline, or high levels (∼160 mmHg, angiotensin II of mean arterial pressure (MAP, n = 5-10 per group were subjected to IOP challenge (10-120 mmHg, 5 mmHg steps every 3 minutes. Electroretinograms were measured at each IOP step to assess bipolar cell (b-wave and inner retinal function (scotopic threshold response or STR. Ocular blood flow was measured using laser-Doppler flowmetry in groups with similar MAP level and the same IOP challenge protocol. Both b-wave and STR amplitudes decreased with IOP elevation. Retinal function was less susceptible to IOP challenge when MAP was high, whereas the converse was true for low MAP. Consistent with the effects on retinal function, higher IOP was needed to attenuated ocular blood flow in animals with higher MAP. The susceptibility of retinal function to IOP challenge can be ameliorated by acute high BP, and exacerbated by low BP. This is partially mediated by modifications in ocular blood flow.

  4. Plasmalemma Vesicle-Associated Protein Has a Key Role in Blood-Retinal Barrier Loss.

    Science.gov (United States)

    Wisniewska-Kruk, Joanna; van der Wijk, Anne-Eva; van Veen, Henk A; Gorgels, Theo G M F; Vogels, Ilse M C; Versteeg, Danielle; Van Noorden, Cornelis J F; Schlingemann, Reinier O; Klaassen, Ingeborg

    2016-04-01

    Loss of blood-retinal barrier (BRB) properties induced by vascular endothelial growth factor (VEGF) and other factors is an important cause of diabetic macular edema. Previously, we found that the presence of plasmalemma vesicle-associated protein (PLVAP) in retinal capillaries associates with loss of BRB properties and correlates with increased vascular permeability in diabetic macular edema. In this study, we investigated whether absence of PLVAP protects the BRB from VEGF-induced permeability. We used lentiviral-delivered shRNA or siRNA to inhibit PLVAP expression. The barrier properties of in vitro BRB models were assessed by measuring transendothelial electrical resistance, permeability of differently sized tracers, and the presence of endothelial junction complexes. The effect of VEGF on caveolae formation was studied in human retinal explants. BRB loss in vivo was studied in the mouse oxygen-induced retinopathy model. The inhibition of PLVAP expression resulted in decreased VEGF-induced BRB permeability of fluorescent tracers, both in vivo and in vitro. PLVAP inhibition attenuated transendothelial electrical resistance reduction induced by VEGF in BRB models in vitro and significantly increased transendothelial electrical resistance of the nonbarrier human umbilical vein endothelial cells. Furthermore, PLVAP knockdown prevented VEGF-induced caveolae formation in retinal explants but did not rescue VEGF-induced alterations in endothelial junction complexes. In conclusion, PLVAP is an essential cofactor in VEGF-induced BRB permeability and may become an interesting novel target for diabetic macular edema therapy.

  5. [Progress of research in retinal image registration].

    Science.gov (United States)

    Yu, Lun; Wei, Lifang; Pan, Lin

    2011-10-01

    The retinal image registration has important applications in the processes of auxiliary diagnosis and treatment for a variety of diseases. The retinal image registration can be used to measure the disease process and the therapeutic effect. A variety of retinal image registration techniques have been studied extensively in recent years. However, there are still many problems existing and there are numerous research possibilities. Based on extensive investigation of existing literatures, the present paper analyzes the feature of retinal image and current challenges of retinal image registration, and reviews the transformation models of the retinal image registration technology and the main research algorithms in current retinal image registration, and analyzes the advantages and disadvantages of various types of algorithms. Some research challenges and future developing trends are also discussed.

  6. Branding of vascular surgery.

    Science.gov (United States)

    Perler, Bruce A

    2008-03-01

    The Society for Vascular Surgery surveyed primary care physicians (PCPs) to understand how PCPs make referral decisions for their patients with peripheral vascular disease. Responses were received from 250 PCPs in 44 states. More than 80% of the respondents characterized their experiences with vascular surgeons as positive or very positive. PCPs perceive that vascular surgeons perform "invasive" procedures and refer patients with the most severe vascular disease to vascular surgeons but were more than twice as likely to refer patients to cardiologists, believing they are better able to perform minimally invasive procedures. Nevertheless, PCPs are receptive to the notion of increasing referrals to vascular surgeons. A successful branding campaign will require considerable education of referring physicians about the totality of traditional vascular and endovascular care increasingly provided by the contemporary vascular surgical practice and will be most effective at the local grassroots level.

  7. Retinal imaging and image analysis

    NARCIS (Netherlands)

    Abramoff, M.D.; Garvin, Mona K.; Sonka, Milan

    2010-01-01

    Many important eye diseases as well as systemic diseases manifest themselves in the retina. While a number of other anatomical structures contribute to the process of vision, this review focuses on retinal imaging and image analysis. Following a brief overview of the most prevalent causes of blindne

  8. Maternal enrichment during pregnancy accelerates retinal development of the fetus.

    Directory of Open Access Journals (Sweden)

    Alessandro Sale

    Full Text Available The influence of maternal environment on fetal development is largely unexplored, the available evidence concerns only the deleterious effects elicited by prenatal stress. Here we investigated the influence of prenatal enrichment on the early development of the visual system in the fetus. We studied the anatomical development of the rat retina, by analyzing the migration of neural progenitors and the process of retinal ganglion cell death, which exerts a key role in sculpturing the developing retinal system at perinatal ages. The number of apoptotic cells in the retinal ganglion cell layer was analyzed using two distinct methods: the presence of pyknotic nuclei stained for cresyl violet and the appearance of DNA fragmentation (Tunel method. We report that environmental enrichment of the mother during pregnancy affects the structural maturation of the retina, accelerating the migration of neural progenitors and the dynamics of natural cell death. These effects seem to be under the control of insulin-like growth factor-I: its levels, higher in enriched pregnant rats and in their milk, are increased also in their offspring, its neutralization abolishes the action of maternal enrichment on retinal development and chronic insulin-like growth factor-I injection to standard-reared females mimics the effects of enrichment in the fetuses. Thus, the development of the visual system is sensitive to environmental stimulation during prenatal life. These findings could have a bearing in orienting clinical research in the field of prenatal therapy.

  9. Vascular dysfunction in preeclampsia.

    Science.gov (United States)

    Brennan, Lesley J; Morton, Jude S; Davidge, Sandra T

    2014-01-01

    Preeclampsia is a complex disorder which affects an estimated 5% of all pregnancies worldwide. It is diagnosed by hypertension in the presence of proteinuria after the 20th week of pregnancy and is a prominent cause of maternal morbidity and mortality. As delivery is currently the only known treatment, preeclampsia is also a leading cause of preterm delivery. Preeclampsia is associated with maternal vascular dysfunction, leading to serious cardiovascular risk both during and following pregnancy. Endothelial dysfunction, resulting in increased peripheral resistance, is an integral part of the maternal syndrome. While the cause of preeclampsia remains unknown, placental ischemia resulting from aberrant placentation is a fundamental characteristic of the disorder. Poor placentation is believed to stimulate the release of a number of factors including pro- and antiangiogenic factors and inflammatory activators into the maternal systemic circulation. These factors are critical mediators of vascular function and impact the endothelium in distinctive ways, including enhanced endothelial oxidative stress. The mechanisms of action and the consequences on the maternal vasculature will be discussed in this review.

  10. Bilateral Hypertensive Retinopathy Complicated with Retinal Neovascularization: Panretinal Photocoagulation or Intravitreal Anti-VEGF Treatment

    Directory of Open Access Journals (Sweden)

    Odysseas Georgiadis

    2014-07-01

    Full Text Available Purpose: To present the case of a patient with bilateral hypertensive retinopathy complicated with retinal neovascularization who received anti-VEGF intravitreal injection in one eye and panretinal photocoagulation (PRP in the fellow eye. Methods: A 33-year-old male patient presented with gradual visual loss in both eyes for the last 5 months. At that time, he was examined by an ophthalmologist and occlusive retinopathy due to malignant systematic hypertension was diagnosed. He was put on antihypertensive treatment but no ophthalmic treatment was undertaken. At presentation, 5 months later, best-corrected visual acuity (BCVA was 0.1 in the right eye (RE and 0.9 in the left eye (LE. Fundus examination was compatible with hypertensive retinopathy complicated with retinal neovascularization. Fluorescein angiography (FFA revealed macular ischemia mainly in the RE and large areas of peripheral retinal ischemia and neovascularization with vascular leakage in both eyes. The patient was treated with two anti-VEGF (ranibizumab injections with 2 months interval in the RE and PRP laser in the LE. Results: Follow-up examination after 12 months showed mild improvement in BCVA, and FFA documented regression of retinal neovascularization in both eyes. Conclusion: Hypertensive retinopathy can be rarely complicated with retinal neovascularization. Treatment with PRP can be undertaken. In our case, the use of an intravitreal anti-VEGF agent seemed to halt its progression satisfactorily.

  11. Retinal detachment in a patient with extensive myelinated retinal nerve fibers.

    Science.gov (United States)

    Chen, Muh-Shy; Ho, Tzyy-Chang; Chang, Ching-Chung; Hou, Ping-Kang

    2007-01-01

    We report extensive myelinated retinal nerve fibers in a 42-year-old patient with retinal detachment. Fundus examination revealed a horseshoe-shaped tear near the temporal edge. Pars plana vitrectomy was performed and firm vitreo-retinal adhesion was noticed in the area of extensive myelinated retinal nerve fibers. Following vitrectomy with silicone oil tamponade, the retina was reattached successfully. In conclusion, retinal detachment may develop in patients with extensive myelinated retinal nerve fibers. Vitrectomy may be performed to treat this condition.

  12. Vasoinhibins regulate the inner and outer blood-retinal barrier and limit retinal oxidative stress

    Directory of Open Access Journals (Sweden)

    David eArredondo Zamarripa

    2014-10-01

    Full Text Available Vasoinhibins are prolactin fragments present in the retina, where they have been shown to prevent the hypervasopermeability associated with diabetes. Enhanced bradykinin (BK production contributes to the increased transport through the blood-retina barrier (BRB in diabetes. Here, we studied if vasoinhibins regulate BRB permeability by targeting the vascular endothelium and retinal pigment epithelium (RPE components of this barrier. Intravitreal injection of BK in male rats increased BRB permeability. Vasoinhibins prevented this effect, as did the B2 receptor antagonist Hoe-140. BK induced a transient decrease in mouse retinal and brain capillary endothelial monolayer resistance that was blocked by vasoinhibins. Both vasoinhibins and the nitric oxide (NO synthase inhibitor L-NAME, but not the antioxidant N-acetyl cysteine (NAC, blocked the transient decrease in bovine umbilical vein endothelial cell (BUVEC monolayer resistance induced by BK; this block was reversed by the NO donor DETANONOate. Vasoinhibins also prevented the BK-induced actin cytoskeleton redistribution, as did L-NAME. BK transiently decreased human RPE (ARPE-19 cell monolayer resistance, and this effect was blocked by vasoinhibins, L-NAME, and NAC. DETANONOate reverted the blocking effect of vasoinhibins. Similar to BK, the radical initiator Luperox induced a reduction in ARPE-19 cell monolayer resistance, which was prevented by vasoinhibins. These effects on RPE resistance coincided with actin cytoskeleton redistribution. Intravitreal injection of vasoinhibins reduced the levels of reactive oxygen species (ROS in retinas of streptozotocin-induced diabetic rats, particularly in the RPE and capillary-containing layers. Thus, vasoinhibins reduce BRB permeability by targeting both its main inner and outer components through NO- and ROS-dependent pathways, offering potential treatment strategies against diabetic retinopathies.

  13. A genetic analysis of retinitis pigmentosa

    Directory of Open Access Journals (Sweden)

    Shanker Jayashree

    1993-01-01

    Full Text Available The data consists of sixty probands affected with Retinitis pigmentosa. Syndromic cases were found in five percent of the RP probands. Segregation analysis was carried out on proband sibship data. The ascertainment probability was estimated at 0.5517. Analysis of the data by parental mating types of proband sibships indicated the presence of dominant forms of RP (2.05%. Analysis of proband sibships indicated the presence of low risk families in the Normal x Normal matings (45% and in the consanguineous matings (40%. The hypothesis of recessive inheritance could be confirmed only in multiplex sibships (p = 0.383 +/- 0.0793. Data on proband matings though incomplete conformed in general to autosomal recessive gene hypothesis.

  14. Novel Mutations in Two Saudi Patients with Congenital Retinal Dystrophy

    OpenAIRE

    Leen Abu Safieh; Al-Otaibi, Humoud M.; Richard Alan Lewis; Igor Kozak

    2016-01-01

    To report novel mutations in two Saudi children with clinical features of Leber congenital amaurosis (LCA) and Alström syndrome. Case reports. Case 1 was a child with phenotypic features of LCA including oculodigital sign, bilateral enophthalmos, nystagmus, pale disc, and retinal changes. Direct sequencing of the coding sequence of GUCY2D revealed a missense mutation affecting highly conserved position (c. 743C > T; p.S248 L). Case 2 describes a girl with marked nystagmus, photophobia, and re...

  15. Society for Vascular Medicine

    Science.gov (United States)

    ... Certification with this new online course from the Society for Vascular Medicine. Learn more. Looking for a ... jobs are listed right now. Copyright © 2016 The Society for Vascular Medicine. All Rights Reserved.

  16. Study of the Influence of Angiostatin Intravitreal Injection on Vascular Leakage in Retina and Iris of the Experimental Diabetic Rats

    Institute of Scientific and Technical Information of China (English)

    Jing Sima; Jianxing Ma; Sarah X.Zhang; Jiang Guo

    2006-01-01

    Purpose: To examine the effect of an intravitreal injection of angiostatin on vascular leakage in retina and iris of the diabetes and study its possible mechanism.Methods: Experimental diabetes was induced in 24 rats by an intravenous injection of streptozotocin (STZ) during 48 adult rats. Three groups were randomization distributed of them. There were 8 of both normal and diabetic rats in each group. STZ-diabetic rats and age-matched normal rats received an intravitreal injection of 5 μl of sterile PBS (Phosphate Buffered Saline) into the right eye, and the left eye was non-injected in the group A; Angiostatin was injected into the vitreous of the right eye (7.5 μg/5μl/eye), and the left eye received the same volume of sterile PBS as the control in the group B and C. The vascular permeability of retina and iris was measured using the Evans blue method at 2 days following the injection in the group A and B. Expres sion of VEGF in retina was evaluated using western blot analysis 24 hours following the injection in the group C.Results: Diabetic rats showed significant increases of vascular permeability in the retina (P<0.01) and iris (P<0.05). Angiostatin-injected eyes showed significant decreases in vascular permeability in the retina (P<0.01) and iris (P<0.05) comparing with the PBS-injected eyes in STZ-diabetic rats. In contrast, intravitreal injection of the same dose of angiostatin into the age-matched normal rats did not result in any significant reduction in vascular permeability in the retina and iris, when compared with the contralateral eye with PBS injection (P>0.05). Angiostatin injection significantly reduced VEGF level in the retinas of STZ-diabetic rats but did not affect retinal VEGF level in normal rats.Conclusions: Angiostatin significantly reduce pathological vascular permeability in the retina and iris of STZ-diabetic rats but not in normal rats. Angiostatin down-regulates VEGF expression and thus, blocks the major cause of vascular

  17. Requirement of Smad4 from Ocular Surface Ectoderm for Retinal Development

    Science.gov (United States)

    Li, Jing; Wang, Shusheng; Anderson, Chastain; Zhao, Fangkun; Qin, Yu; Wu, Di; Wu, Xinwei; Liu, Jia; He, Xuefei; Zhao, Jiangyue; Zhang, Jinsong

    2016-01-01

    Microphthalmia is characterized by abnormally small eyes and usually retinal dysplasia, accounting for up to 11% of the blindness in children. Right now there is no effective treatment for the disease, and the underlying mechanisms, especially how retinal dysplasia develops from microphthalmia and whether it depends on the signals from lens ectoderm are still unclear. Mutations in genes of the TGF-β superfamily have been noted in patients with microphthalmia. Using conditional knockout mice, here we address the question that whether ocular surface ectoderm-derived Smad4 modulates retinal development. We found that loss of Smad4 specifically on surface lens ectoderm leads to microphthalmia and dysplasia of retina. Retinal dysplasia in the knockout mice is caused by the delayed or failed differentiation and apoptosis of retinal cells. Microarray analyses revealed that members of Hedgehog and Wnt signaling pathways are affected in the knockout retinas, suggesting that ocular surface ectoderm-derived Smad4 can regulate Hedgehog and Wnt signaling in the retina. Our studies suggest that defective of ocular surface ectoderm may affect retinal development. PMID:27494603

  18. Tyro3 Modulates Mertk-Associated Retinal Degeneration.

    Science.gov (United States)

    Vollrath, Douglas; Yasumura, Douglas; Benchorin, Gillie; Matthes, Michael T; Feng, Wei; Nguyen, Natalie M; Sedano, Cecilia D; Calton, Melissa A; LaVail, Matthew M

    2015-12-01

    Inherited photoreceptor degenerations (IPDs) are the most genetically heterogeneous of Mendelian diseases. Many IPDs exhibit substantial phenotypic variability, but the basis is usually unknown. Mutations in MERTK cause recessive IPD phenotypes associated with the RP38 locus. We have identified a murine genetic modifier of Mertk-associated photoreceptor degeneration, the C57BL/6 (B6) allele of which acts as a suppressor. Photoreceptors degenerate rapidly in Mertk-deficient animals homozygous for the 129P2/Ola (129) modifier allele, whereas animals heterozygous for B6 and 129 modifier alleles exhibit an unusual intermixing of degenerating and preserved retinal regions, with females more severely affected than males. Mertk-deficient mice homozygous for the B6 modifier allele display degeneration only in the far periphery, even at 8 months of age, and have improved retinal function compared to animals homozygous for the 129 allele. We genetically mapped the modifier to an approximately 2-megabase critical interval that includes Tyro3, a paralog of Mertk. Tyro3 expression in the outer retina varies with modifier genotype in a manner characteristic of a cis-acting expression quantitative trait locus (eQTL), with the B6 allele conferring an approximately three-fold higher expression level. Loss of Tyro3 function accelerates the pace of photoreceptor degeneration in Mertk knockout mice, and TYRO3 protein is more abundant in the retinal pigment epithelium (RPE) adjacent to preserved central retinal regions of Mertk knockout mice homozygous for the B6 modifier allele. Endogenous human TYRO3 protein co-localizes with nascent photoreceptor outer segment (POS) phagosomes in a primary RPE cell culture assay, and expression of murine Tyro3 in cultured cells stimulates phagocytic ingestion of POS. Our findings demonstrate that Tyro3 gene dosage modulates Mertk-associated retinal degeneration, provide strong evidence for a direct role for TYRO3 in RPE phagocytosis, and suggest

  19. Tyro3 Modulates Mertk-Associated Retinal Degeneration.

    Directory of Open Access Journals (Sweden)

    Douglas Vollrath

    2015-12-01

    Full Text Available Inherited photoreceptor degenerations (IPDs are the most genetically heterogeneous of Mendelian diseases. Many IPDs exhibit substantial phenotypic variability, but the basis is usually unknown. Mutations in MERTK cause recessive IPD phenotypes associated with the RP38 locus. We have identified a murine genetic modifier of Mertk-associated photoreceptor degeneration, the C57BL/6 (B6 allele of which acts as a suppressor. Photoreceptors degenerate rapidly in Mertk-deficient animals homozygous for the 129P2/Ola (129 modifier allele, whereas animals heterozygous for B6 and 129 modifier alleles exhibit an unusual intermixing of degenerating and preserved retinal regions, with females more severely affected than males. Mertk-deficient mice homozygous for the B6 modifier allele display degeneration only in the far periphery, even at 8 months of age, and have improved retinal function compared to animals homozygous for the 129 allele. We genetically mapped the modifier to an approximately 2-megabase critical interval that includes Tyro3, a paralog of Mertk. Tyro3 expression in the outer retina varies with modifier genotype in a manner characteristic of a cis-acting expression quantitative trait locus (eQTL, with the B6 allele conferring an approximately three-fold higher expression level. Loss of Tyro3 function accelerates the pace of photoreceptor degeneration in Mertk knockout mice, and TYRO3 protein is more abundant in the retinal pigment epithelium (RPE adjacent to preserved central retinal regions of Mertk knockout mice homozygous for the B6 modifier allele. Endogenous human TYRO3 protein co-localizes with nascent photoreceptor outer segment (POS phagosomes in a primary RPE cell culture assay, and expression of murine Tyro3 in cultured cells stimulates phagocytic ingestion of POS. Our findings demonstrate that Tyro3 gene dosage modulates Mertk-associated retinal degeneration, provide strong evidence for a direct role for TYRO3 in RPE phagocytosis

  20. [Vitreo-retinal surgery for complicated retinal detachment].

    Science.gov (United States)

    Wang, J Z

    1993-07-01

    93 eyes (93 patients) of complicated retinal detachment were treated with vitreo-retinal surgery. Among the series, 75 eyes were rhegmatogenous with PVR C3-D3 in 66 eyes (88.0%), while the remaining 18 eyes were traction induced. None of the cases had giant tears or complicating diabetes. On discharge from the hospital, the operation was effective in 62 cases (66.7%), in whom the retina was totally reattached or only a small amount of subretinal fluid remained. In a group of 40 eyes where the inert gas SF6 was used, the operation was effective in 30 cases (75.0%). 41 cases were followed up postoperatively for over 3 months, averaging 13.7 months, to find the operative results stable in 33 eyes (80.5%), with the visual acuity improved in 22 cases (66.7%), unchanged in 9 cases (27.3%), and decreased in 2 cases (6.0%). The operative procedures, the peeling of pre-retinal membrane, the effect of PVR severity on the operative results, and the promotion of operative efficacy by application of wide encircling buckle and inert gas tamponade were discussed.

  1. Vascular grading of angiogenesis

    DEFF Research Database (Denmark)

    Hansen, S; Grabau, D A; Sørensen, Flemming Brandt;

    2000-01-01

    was moderately reproduced (kappa = 0.59). Vascular grade was significantly associated with axillary node involvement, tumour size, malignancy grade, oestrogen receptor status and histological type. In univariate analyses vascular grade significantly predicted recurrence free survival and overall survival for all...... patients (P analysis showed that vascular grading contributed with independent prognostic value in all patients (P

  2. Vascular malformations in the maxillofacial region

    Directory of Open Access Journals (Sweden)

    M. Jafari

    1994-06-01

    Full Text Available Congenital vascular lesions occur most often in children. Parents of these children take them to maxillofacial surgeons directly or during the treatment of other complications such as infection or jaw bone disorders. Various terms now used are unable to describe the pathogenesis and mechanism of the effect of vascular lesions on growth and development of facial bone.  Term of hemangioma is used in almost all cases of congenital and acquired vascular lesions, while fibrosis or shrinkage occurs in some of these lesions over the time. There is also some confusion in describing the vascular lesions which primarily affected bones and soft tissue vascular malformations associated with changes in hard tissues.

  3. The role of Zic family zinc finger transcription factors in the proliferation and differentiation of retinal progenitor cells

    Energy Technology Data Exchange (ETDEWEB)

    Watabe, Yui [Division of Molecular and Developmental Biology, Institute of Medical Science, University of Tokyo (Japan); Department of Ophthalmology, Teikyo University School of Medicine, Tokyo (Japan); Division of Orthoptics, Teikyo University School of Medical Care and Technology, Tokyo (Japan); Baba, Yukihiro [Division of Molecular and Developmental Biology, Institute of Medical Science, University of Tokyo (Japan); Nakauchi, Hiromitsu [Division of Stem Cell Therapy, Center for Stem Cell Biology and Regenerative Medicine, Institute of Medical Science, University of Tokyo (Japan); Mizota, Atsushi [Department of Ophthalmology, Teikyo University School of Medicine, Tokyo (Japan); Watanabe, Sumiko, E-mail: sumiko@ims.u-tokyo.ac.jp [Division of Molecular and Developmental Biology, Institute of Medical Science, University of Tokyo (Japan)

    2011-11-11

    Highlights: Black-Right-Pointing-Pointer Zic transcription factors expressed early retinal progenitor cells. Black-Right-Pointing-Pointer Zics sustain proliferation activity of retinal progenitor cells. Black-Right-Pointing-Pointer Overexpression of Zic in retinal progenitors perturbed rod differentiation. Black-Right-Pointing-Pointer Fate determination to rod photoreceptor was not affected. -- Abstract: Members of the Zic family of zinc finger transcription factors play critical roles in a variety of developmental processes. Using DNA microarray analysis, we found that Zics are strongly expressed in SSEA-1-positive early retinal progenitors in the peripheral region of the mouse retina. Reverse-transcription polymerase chain reaction using mRNA from the retina at various developmental stages showed that Zic1 and Zic2 are expressed in the embryonic retina and then gradually disappear during retinal development. Zic3 is also expressed in the embryonic retina; its expression level slightly decreases but it is expressed until adulthood. We overexpressed Zic1, Zic2, or Zic3 in retinal progenitors at embryonic day 17.5 and cultured the retina as explants for 2 weeks. The number of rod photoreceptors was fewer than in the control, but no other cell types showed significant differences between control and Zic overexpressing cells. The proliferation activity of normal retinal progenitors decreased after 5 days in culture, as observed in normal in vivo developmental processes. However, Zic expressing retinal cells continued to proliferate at days 5 and 7, suggesting that Zics sustain the proliferation activities of retinal progenitor cells. Since the effects of Zic1, 2, and 3 are indistinguishable in terms of differentiation and proliferation of retinal progenitors, the redundant function of Zics in retinal development is suggested.

  4. Advances in Retinal Stem Cell Biology

    Directory of Open Access Journals (Sweden)

    Andrea S Viczian

    2013-01-01

    Full Text Available Tremendous progress has been made in recent years to generate retinal cells from pluripotent cell sources. These advances provide hope for those suffering from blindness due to lost retinal cells. Understanding the intrinsic genetic network in model organisms, like fly and frog, has led to a better understanding of the extrinsic signaling pathways necessary for retinal progenitor cell formation in mouse and human cell cultures. This review focuses on the culture methods used by different groups, which has culminated in the generation of laminated retinal tissue from both embryonic and induced pluripotent cells. The review also briefly describes advances made in transplantation studies using donor retinal progenitor and cultured retinal cells.

  5. MicroRNA signature and function in retinal neovascularization

    Institute of Scientific and Technical Information of China (English)

    Saloni; Agrawal; Brahim; Chaqour

    2014-01-01

    Ischemic retinopathies are clinically well-defined chronic microvascular complications characterized by gradually progressive alterations in the retinal microvasculature and a compensatory aberrant neovascularization of the eye. The subsequent metabolic deficiencies result in structural and functional alterations in the retina which is highly susceptible to injurious stimuli such as diabe-tes, trauma, hyperoxia, inflammation, aging and dys-plipidemia. Emerging evidence indicates that an effec-tive therapy may require targeting multiple components of the angiogenic pathway. Conceptually, mircoRNA(miRNA)-based therapy provides the rationale basis for an effective antiangiogenic treatment. miRNAs are an evolutionarily conserved family of short RNAs, each regulating the expression of multiple protein-coding genes. The activity of specific miRNAs is important for vascular cell signaling and blood vessel formation and function. Recently, important progress has been made in mapping the miRNA-gene target network andmiRNA-mediated gene expression control. Here wehighlight the latest findings on angiogenic and antian-giogenic miRNAs and their targets as well as potentiaimplications in ocular neovascular diseases. Emphasis isplaced on how specific vascular-enriched miRNAs regu-late cell responses to various cues by targeting severafactors, receptors and/or signaling molecules in orderto maintain either vascular function or dysfunction. Fur-ther improvement of our knowledge in not only miRNAspecificity, turnover, and transport but also how miRNAsequences and functions can be altered will enhancethe therapeutic utility of such molecules.

  6. Retinal Cell Degeneration in Animal Models

    OpenAIRE

    Masayuki Niwa; Hitomi Aoki; Akihiro Hirata; Hiroyuki Tomita; Green, Paul G.; Akira Hara

    2016-01-01

    The aim of this review is to provide an overview of various retinal cell degeneration models in animal induced by chemicals (N-methyl-d-aspartate- and CoCl2-induced), autoimmune (experimental autoimmune encephalomyelitis), mechanical stress (optic nerve crush-induced, light-induced) and ischemia (transient retinal ischemia-induced). The target regions, pathology and proposed mechanism of each model are described in a comparative fashion. Animal models of retinal cell degeneration provide insi...

  7. Ursodeoxycholic Acid Attenuates Endoplasmic Reticulum Stress-Related Retinal Pericyte Loss in Streptozotocin-Induced Diabetic Mice

    Directory of Open Access Journals (Sweden)

    Yoo-Ri Chung

    2017-01-01

    Full Text Available Loss of pericytes, an early hallmark of diabetic retinopathy (DR, results in breakdown of the blood-retinal barrier. Endoplasmic reticulum (ER stress may be involved in this process. The purpose of this study was to examine the effects of ursodeoxycholic acid (UDCA, a known ameliorator of ER stress, on pericyte loss in DR of streptozotocin- (STZ- induced diabetic mice. To assess the extent of DR, the integrity of retinal vessels and density of retinal capillaries in STZ-induced diabetic mice were evaluated. Additionally, induction of ER stress and the unfolded protein response (UPR were assessed in diabetic mice and human retinal pericytes exposed to advanced glycation end products (AGE or modified low-density lipoprotein (mLDL. Fluorescein dye leakage during angiography and retinal capillary density were improved in UDCA-treated diabetic mice, compared to the nontreated diabetic group. Among the UPR markers, those involved in the protein kinase-like ER kinase (PERK pathway were increased, while UDCA attenuated UPR in STZ-induced diabetic mice as well as AGE- or mLDL-exposed retinal pericytes in culture. Consequently, vascular integrity was improved and pericyte loss reduced in the retina of STZ-induced diabetic mice. Our findings suggest that UDCA might be effective in protecting against DR.

  8. Intrinsically photosensitive retinal ganglion cells

    Institute of Scientific and Technical Information of China (English)

    Gary; E.PICKARD; Patricia; J.SOLLARS

    2010-01-01

    A new mammalian photoreceptor was recently discovered to reside in the ganglion cell layer of the inner retina.These intrinsically photosensitive retinal ganglion cells(ipRGCs) express a photopigment,melanopsin,that confers upon them the ability to respond to light in the absence of all rod and cone photoreceptor input.Although relatively few in number,ipRGCs extend their dendrites across large expanses of the retina making them ideally suited to function as irradiance detectors to assess changes in ambient light levels.Phototransduction in ipRGCs appears to be mediated by transient receptor potential channels more closely resembling the phototransduction cascade of invertebrate rather than vertebrate photoreceptors.ipRGCs convey irradiance information centrally via the optic nerve to influence several functions.ipRGCs are the primary retinal input to the hypothalamic suprachiasmatic nucleus(SCN),a circadian oscillator and biological clock,and this input entrains the SCN to the day/night cycle.ipRGCs contribute irradiance signals that regulate pupil size and they also provide signals that interface with the autonomic nervous system to regulate rhythmic gene activity in major organs of the body.ipRGCs also provide excitatory drive to dopaminergic amacrine cells in the retina,providing a novel basis for the restructuring of retinal circuits by light.Here we review the ground-breaking discoveries,current progress and directions for future investigation.

  9. Retinal Macroglial Responses in Health and Disease

    Directory of Open Access Journals (Sweden)

    Rosa de Hoz

    2016-01-01

    Full Text Available Due to their permanent and close proximity to neurons, glial cells perform essential tasks for the normal physiology of the retina. Astrocytes and Müller cells (retinal macroglia provide physical support to neurons and supplement them with several metabolites and growth factors. Macroglia are involved in maintaining the homeostasis of extracellular ions and neurotransmitters, are essential for information processing in neural circuits, participate in retinal glucose metabolism and in removing metabolic waste products, regulate local blood flow, induce the blood-retinal barrier (BRB, play fundamental roles in local immune response, and protect neurons from oxidative damage. In response to polyetiological insults, glia cells react with a process called reactive gliosis, seeking to maintain retinal homeostasis. When malfunctioning, macroglial cells can become primary pathogenic elements. A reactive gliosis has been described in different retinal pathologies, including age-related macular degeneration (AMD, diabetes, glaucoma, retinal detachment, or retinitis pigmentosa. A better understanding of the dual, neuroprotective, or cytotoxic effect of macroglial involvement in retinal pathologies would help in treating the physiopathology of these diseases. The extensive participation of the macroglia in retinal diseases points to these cells as innovative targets for new drug therapies.

  10. Blockade of Vascular Endothelial Growth Factor Receptor 1 Prevents Inflammation and Vascular Leakage in Diabetic Retinopathy

    Directory of Open Access Journals (Sweden)

    Jianbo He

    2015-01-01

    Full Text Available Diabetic retinopathy (DR is a leading cause of blindness in working age adults. The objective of this study is to investigate the effects of vascular endothelial growth factor receptor 1 (VEGFR1 blockade on the complications of DR. Experimental models of diabetes were induced with streptozotocin (STZ treatment or Insulin2 gene mutation (Akita in mice. Protein expression and localization were examined by western blots (WB and immunofluorescence (IF. mRNA expression was quantified by PCR array and real-time PCR. The activity of VEGFR1 signaling was blocked by a neutralizing antibody called MF1. Vascular leakage was evaluated by measuring the leakage of [3H]-mannitol tracer into the retina and the IF staining of albumin. VEGFR1 blockade significantly inhibited diabetes-related vascular leakage, leukocytes-endothelial cell (EC adhesion (or retinal leukostasis, expression of intercellular adhesion molecule- (ICAM- 1 protein, abnormal localization and degeneration of the tight junction protein zonula occludens- (ZO- 1, and the cell adhesion protein vascular endothelial (VE cadherin. In addition, VEGFR1 blockade interfered with the gene expression of 10 new cytokines and chemokines: cxcl10, il10, ccl8, il1f6, cxcl15, ccl4, il13, ccl6, casp1, and ccr5. These results suggest that VEGFR1 mediates complications of DR and targeting this signaling pathway represents a potential therapeutic strategy for the prevention and treatment of DR.

  11. Clinical characteristics and current therapies for inherited retinal degenerations.

    Science.gov (United States)

    Sahel, José-Alain; Marazova, Katia; Audo, Isabelle

    2014-10-16

    Inherited retinal degenerations (IRDs) encompass a large group of clinically and genetically heterogeneous diseases that affect approximately 1 in 3000 people (>2 million people worldwide) (Bessant DA, Ali RR, Bhattacharya SS. 2001. Molecular genetics and prospects for therapy of the inherited retinal dystrophies. Curr Opin Genet Dev 11: 307-316.). IRDs may be inherited as Mendelian traits or through mitochondrial DNA, and may affect the entire retina (e.g., rod-cone dystrophy, also known as retinitis pigmentosa, cone dystrophy, cone-rod dystrophy, choroideremia, Usher syndrome, and Bardet-Bidel syndrome) or be restricted to the macula (e.g., Stargardt disease, Best disease, and Sorsby fundus dystrophy), ultimately leading to blindness. IRDs are a major cause of severe vision loss, with profound impact on patients and society. Although IRDs remain untreatable today, significant progress toward therapeutic strategies for IRDs has marked the past two decades. This progress has been based on better understanding of the pathophysiological pathways of these diseases and on technological advances.

  12. Hereditary retinal disease : clinical and genetic studies on the role of the peripherin/RDS gene , the BEST1 gene, and the CFH gene

    NARCIS (Netherlands)

    Boon, C.J.F.

    2009-01-01

    Mutations in the peripherin/RDS gene, the BEST1 gene, and the CFH gene appear to be relatively frequent causes of hereditary retinal diseases that principally affect the macula. Intriguingly, a single mutation may be associated with a broad range of retinal phenotypes. Even in a single family, one m

  13. Hypoxia inducible factor-2α regulates the development of retinal astrocytic network by maintaining adequate supply of astrocyte progenitors.

    Directory of Open Access Journals (Sweden)

    Li-Juan Duan

    Full Text Available Here we investigate the role of hypoxia inducible factor (HIF-2α in coordinating the development of retinal astrocytic and vascular networks. Three Cre mouse lines were used to disrupt floxed Hif-2α, including Rosa26(CreERT2, Tie2(Cre, and GFAP(Cre. Global Hif-2α disruption by Rosa26(CreERT2 led to reduced astrocytic and vascular development in neonatal retinas, whereas endothelial disruption by Tie2(Cre had no apparent effects. Hif-2α deletion in astrocyte progenitors by GFAP(Cre significantly interfered with the development of astrocytic networks, which failed to reach the retinal periphery and were incapable of supporting vascular development. Perplexingly, the abundance of strongly GFAP(+ mature astrocytes transiently increased at P0 before they began to lag behind the normal controls by P3. Pax2(+ and PDGFRα(+ astrocytic progenitors and immature astrocytes were dramatically diminished at all stages examined. Despite decreased number of astrocyte progenitors, their proliferation index or apoptosis was not altered. The above data can be reconciled by proposing that HIF-2α is required for maintaining the supply of astrocyte progenitors by slowing down their differentiation into non-proliferative mature astrocytes. HIF-2α deficiency in astrocyte progenitors may accelerate their differentiation into astrocytes, a change which greatly interferes with the replenishment of astrocyte progenitors due to insufficient time for proliferation. Rapidly declining progenitor supply may lead to premature cessation of astrocyte development. Given that HIF-2α protein undergoes oxygen dependent degradation, an interesting possibility is that retinal blood vessels may regulate astrocyte differentiation through their oxygen delivery function. While our findings support the consensus that retinal astrocytic template guides vascular development, they also raise the possibility that astrocytic and vascular networks may mutually regulate each other

  14. Retinal Mueller glial cells trigger the hallmark inflammatory process in autoimmune uveitis.

    Science.gov (United States)

    Hauck, Stefanie M; Schoeffmann, Stephanie; Amann, Barbara; Stangassinger, Manfred; Gerhards, Hartmut; Ueffing, Marius; Deeg, Cornelia A

    2007-06-01

    Spontaneous equine recurrent uveitis (ERU) is an incurable autoimmune disease affecting the eye. Although retinal-autoantigen specific T-helper 1 cells have been demonstrated to trigger disease progression and relapses, the molecular processes leading to retinal degeneration and consequent blindness remain unknown. To elucidate such processes, we studied changes in the total retinal proteome of ERU-diseased horses compared to healthy controls. Severe changes in the retinal proteome were found for several markers for blood-retinal barrier breakdown and whose emergence depended upon disease severity. Additionally, uveitic changes in the retina were accompanied by upregulation of aldose 1-epimerase, selenium-binding protein 1, alpha crystallin A chain, phosphatase 2A inhibitor (SET), and glial fibrillary acidic protein (GFAP), the latter indicating an involvement of retinal Mueller glial cells (RMG) in disease process. To confirm this, we screened for additional RMG-specific markers and could demonstrate that, in uveitic retinas, RMG concomitantly upregulate vimentin and GFAP and downregulate glutamine synthetase. These expression patterns suggest for an activated state of RMG, which further downregulate the expression of pigment epithelium-derived factor (PEDF) and begin expressing interferon-gamma, a pro-inflammatory cytokine typical for T-helper 1 cells. We thus propose that RMG may play a fatal role in uveitic disease progression by directly triggering inflammatory processes through the expression and secretion of interferon-gamma.

  15. Neuroprotective effects of citicoline in in vitro models of retinal neurodegeneration.

    Science.gov (United States)

    Matteucci, Andrea; Varano, Monica; Gaddini, Lucia; Mallozzi, Cinzia; Villa, Marika; Pricci, Flavia; Malchiodi-Albedi, Fiorella

    2014-04-14

    In recent years, citicoline has been the object of remarkable interest as a possible neuroprotectant. The aim of this study was to investigate if citicoline affected cell survival in primary retinal cultures and if it exerted neuroprotective activity in conditions modeling retinal neurodegeneration. Primary retinal cultures, obtained from rat embryos, were first treated with increasing concentrations of citicoline (up to 1000 µM) and analyzed in terms of apoptosis and caspase activation and characterized by immunocytochemistry to identify neuronal and glial cells. Subsequently, excitotoxic concentration of glutamate or High Glucose-containing cell culture medium (HG) was administered as well-known conditions modeling neurodegeneration. Glutamate or HG treatments were performed in the presence or not of citicoline. Neuronal degeneration was evaluated in terms of apoptosis and loss of synapses. The results showed that citicoline did not cause any damage to the retinal neuroglial population up to 1000 µM. At the concentration of 100 µM, it was able to counteract neuronal cell damage both in glutamate- and HG-treated retinal cultures by decreasing proapoptotic effects and contrasting synapse loss. These data confirm that citicoline can efficiently exert a neuroprotective activity. In addition, the results suggest that primary retinal cultures, under conditions inducing neurodegeneration, may represent a useful system to investigate citicoline neuroprotective mechanisms.

  16. Neuroprotective Effects of Citicoline in in Vitro Models of Retinal Neurodegeneration

    Directory of Open Access Journals (Sweden)

    Andrea Matteucci

    2014-04-01

    Full Text Available In recent years, citicoline has been the object of remarkable interest as a possible neuroprotectant. The aim of this study was to investigate if citicoline affected cell survival in primary retinal cultures and if it exerted neuroprotective activity in conditions modeling retinal neurodegeneration. Primary retinal cultures, obtained from rat embryos, were first treated with increasing concentrations of citicoline (up to 1000 µM and analyzed in terms of apoptosis and caspase activation and characterized by immunocytochemistry to identify neuronal and glial cells. Subsequently, excitotoxic concentration of glutamate or High Glucose-containing cell culture medium (HG was administered as well-known conditions modeling neurodegeneration. Glutamate or HG treatments were performed in the presence or not of citicoline. Neuronal degeneration was evaluated in terms of apoptosis and loss of synapses. The results showed that citicoline did not cause any damage to the retinal neuroglial population up to 1000 µM. At the concentration of 100 µM, it was able to counteract neuronal cell damage both in glutamate- and HG-treated retinal cultures by decreasing proapoptotic effects and contrasting synapse loss. These data confirm that citicoline can efficiently exert a neuroprotective activity. In addition, the results suggest that primary retinal cultures, under conditions inducing neurodegeneration, may represent a useful system to investigate citicoline neuroprotective mechanisms.

  17. Automated characterization of blood vessels as arteries and veins in retinal images.

    Science.gov (United States)

    Mirsharif, Qazaleh; Tajeripour, Farshad; Pourreza, Hamidreza

    2013-01-01

    In recent years researchers have found that alternations in arterial or venular tree of the retinal vasculature are associated with several public health problems such as diabetic retinopathy which is also the leading cause of blindness in the world. A prerequisite for automated assessment of subtle changes in arteries and veins, is to accurately separate those vessels from each other. This is a difficult task due to high similarity between arteries and veins in addition to variation of color and non-uniform illumination inter and intra retinal images. In this paper a novel structural and automated method is presented for artery/vein classification of blood vessels in retinal images. The proposed method consists of three main steps. In the first step, several image enhancement techniques are employed to improve the images. Then a specific feature extraction process is applied to separate major arteries from veins. Indeed, vessels are divided to smaller segments and feature extraction and vessel classification are applied to each small vessel segment instead of each vessel point. Finally, a post processing step is added to improve the results obtained from the previous step using structural characteristics of the retinal vascular network. In the last stage, vessel features at intersection and bifurcation points are processed for detection of arterial and venular sub trees. Ultimately vessel labels are revised by publishing the dominant label through each identified connected tree of arteries or veins. Evaluation of the proposed approach against two different datasets of retinal images including DRIVE database demonstrates the good performance and robustness of the method. The proposed method may be used for determination of arteriolar to venular diameter ratio in retinal images. Also the proposed method potentially allows for further investigation of labels of thinner arteries and veins which might be found by tracing them back to the major vessels.

  18. The long-term relation among retinal arteriolar narrowing, blood pressure, and incident severe hypertension.

    Science.gov (United States)

    Wang, Jie Jin; Rochtchina, Elena; Liew, Gerald; Tan, Ava G; Wong, Tien Yin; Leeder, Stephen R; Smith, Wayne; Shankar, Anoop; Mitchell, Paul

    2008-07-01

    The authors assessed associations between retinal vascular signs and incident severe hypertension in an older population-based cohort. At baseline (1992-1994), 3,654 residents aged 49-97 years living in the Blue Mountains area west of Sydney, Australia, were examined; respectively, 2,335 (75.1%) and 1,952 (76%) survivors were reexamined 5 and 10 years later. Retinal arteriolar and venular calibers were measured, and average central retinal artery and central retinal vein equivalents for that eye were estimated. Severe hypertension was defined by previous diagnosis of hypertension plus antihypertensive medication use or by systolic blood pressure > or =160 mmHg and/or diastolic blood pressure > or =100 mmHg at examinations. Of the 1,424 participants at risk, 618 developed severe hypertension over 10 years (cumulative incidence = 47.7%, 95% confidence interval: 44.9, 50.5). Participants who subsequently developed severe hypertension had significantly narrower mean central retinal artery equivalents than those who did not (187.0 vs. 191.9 mum, p < 0.0001). After adjusting for age, sex, body mass index, smoking, mean arterial blood pressure, and plasma glucose and triglyceride levels, baseline narrowing central retinal artery equivalent was associated with increased risk of severe hypertension (per standard deviation reduction, odds ratio = 1.1, 95% confidence interval: 1.1, 1.2; narrowest vs. widest quintile, odds ratio = 1.6, 95% confidence interval: 1.2, 2.1). These findings support structural narrowing in small arteries and arterioles antecedent to clinical onset of severe hypertension.

  19. Characteristics of retinal reflectance changes induced by transcorneal electrical stimulation in cat eyes.

    Directory of Open Access Journals (Sweden)

    Takeshi Morimoto

    Full Text Available Transcorneal electrical stimulation (TES activates retinal neurons leading to visual sensations. How the retinal cells are activated by TES has not been definitively determined. Investigating the reflectance changes of the retina is an established technique and has been used to determine the mechanism of retinal activation. The purpose of this study was to evaluate the reflectance changes elicited by TES in cat eyes. Eight eyes of Eight cats were studied under general anesthesia. Biphasic electrical pulses were delivered transcornealy. The fundus images observed with near-infrared light (800-880 nm were recorded every 25 ms for 26 s. To improve the signal-to-noise ratio, the images of 10 consecutive recordings were averaged. Two-dimensional topographic maps of the reflective changes were constructed by subtracting images before from those after the TES. The effects of different stimulus parameters, e.g., current intensity, pulse duration, frequency, and stimulus duration, on the reflective changes were studied. Our results showed that after TES, the reflective changes appeared on the retinal vessels and optic disc. The intensity of reflectance changes increased as the current intensity, pulse duration, and stimulation duration increased (P<0.05 for all. The maximum intensity of the reflective change was obtained when the stimulus frequency was 20 Hz. The time course of the reflectance changes was also altered by the stimulation parameters. The response started earlier and returned to the baseline later with higher current intensities, longer pulse durations, but the time of the peak of the response was not changed. These results showed that the reflective changes were due to the activation of retinal neurons by TES and might involve the vascular changes induced by an activation of the retinal neurons.

  20. Early interventions to prevent retinal vasculopathy in diabetes: a review

    Directory of Open Access Journals (Sweden)

    Harrison WW

    2015-08-01

    Full Text Available Wendy W Harrison, Vladimir YevseyenkovArizona College of Optometry, Midwestern University, Glendale, AZ, USAAbstract: Diabetic eye disease is a public health concern in all areas of the world as a leading cause of blindness in the working aged to elderly populations. Diabetes damages the lining of the microvasculature throughout the body through prolonged exposure to hyperglycemic conditions. The ocular changes are progressive with very little recourse for improvement once damage begins. Current treatments for the eye focus mainly on the late stages of the disease when neovascularization or edema threatens sight. Early interventions for diabetic vasculopathy involve metabolic therapy to improve blood glucose and blood pressure control. Technology improvements have a large part to play in advancing diagnosis of diabetic eye disease. These new technologies offer both structural and functional means for assessment of retinal health. This review focuses on current treatments for diabetic eye disease at all stages with an emphasis on new and early interventions. It also details established and emerging technologies used for earlier detection of diabetic eye disease, which is vital to the development and approval of much needed treatments targeted at earlier stages of diabetic retinopathy. Possible future treatments should be aimed to prevent retinal vasculopathy from progressing. This review will explore current research on this topic and what is needed moving forward.Keywords: diabetes, diabetic retinopathy, vascular disease

  1. Evaluation of Retinal Changes Using Optical Coherence Tomography in a Pediatric Case of Susac Syndrome

    Directory of Open Access Journals (Sweden)

    Mehmet Kola

    2017-01-01

    Full Text Available Susac syndrome is a rare occlusive vasculopathy affecting the retina, inner ear and brain. The cause is unknown, although it generally affects young women. This syndrome can be difficult to diagnose because its signs can only be revealed by detailed examination. These signs are not always concomitant, but may appear at different times. This report describes a pediatric case who was diagnosed with Susac syndrome when retinal lesions were identified in the inactive period with the help of optical coherence tomography (OCT. The purpose of this case report is to emphasize the importance of OCT in clarifying undefined retinal changes in Susac syndrome.

  2. Aldosterone and vascular damage.

    Science.gov (United States)

    Duprez, D; De Buyzere, M; Rietzschel, E R; Clement, D L

    2000-06-01

    Although the aldosterone escape mechanism is well known, aldosterone has often been neglected in the pathophysiologic consequences of the activated renin-angiotensin-aldosterone system in arterial hypertension and chronic heart failure. There is now evidence for vascular synthesis of aldosterone aside from its secretion by the adrenal cortex. Moreover, aldosterone is involved in vascular smooth muscle cell hypertrophy and hyperplasia, as well as in vascular matrix impairment and endothelial dysfunction. The mechanisms of action of aldosterone may be either delayed (genomic) or rapid (nongenomic). Deleterious effects of aldosterone leading to vascular target-organ damage include (besides salt and water retention) decreased arterial and venous compliance, increased peripheral vascular resistance, and impaired autonomic vascular control due to baroreflex dysfunction.

  3. Anatomy of the retinal nerve fiber layer.

    Science.gov (United States)

    Radius, R L; de Bruin, J

    1981-11-01

    Anatomy of the retinal nerve fiber layer in rabbit eyes is studied by light microscopy, transmission electron microscopy, and scanning electron microscopy. It is demonstrated that retinal striations noted ophthalmoscopically in these eyes represent individual fiber bundles, Axon bundles are compartmentalized within tissue tunnels comprised of elongated processes of glial cell origin.

  4. Argus II retinal prosthesis system: An update.

    Science.gov (United States)

    Rachitskaya, Aleksandra V; Yuan, Alex

    2016-09-01

    This review focuses on a description of the Argus II retinal prosthesis system (Argus II; Second Sight Medical Products, Sylmar, CA) that was approved for humanitarian use by the FDA in 2013 in patients with retinitis pigmentosa with bare or no light perception vision. The article describes the components of Argus II, the studies on the implant, and future directions.

  5. Retinal ischemia and embolism. Causes and outcomes

    NARCIS (Netherlands)

    Wijman, C.A.C.

    2007-01-01

    The ocular fundus allows direct visualization of the retinal vasculature, blood vessels that are part of the cerebral circulation. Unraveling the causes of retinal ischemia may provide further insight in the pathophysiological processes that underlie cerebral ischemia. The primary aim of the studies

  6. Plasmalogens in the retina: from occurrence in retinal cell membranes to potential involvement in pathophysiology of retinal diseases.

    Science.gov (United States)

    Saab, Sarah; Mazzocco, Julie; Creuzot-Garcher, Catherine P; Bron, Alain M; Bretillon, Lionel; Acar, Niyazi

    2014-12-01

    Plasmalogens (Pls) represent a specific subclass of glycerophospholipids characterized by the presence of a vinyl-ether bond at the sn-1 position of glycerol. Pls are quantitatively important in membranes of neuronal tissues, including the brain and the retina, where they can represent until almost two-third of ethanolamine glycerophospholipids. They are considered as reservoirs of polyunsaturated fatty acids as several studies have shown that arachidonic and docosahexaenoic acids are preferentially esterified on Pls when compared to other glycerophospholipids. Reduced levels of Pls were observed in a number of neurodegenerative disorders such as glaucoma, the second leading cause of blindness worldwide. In a mouse model of Pls deficiency, "glaucoma-like" optic nerve abnormalities were observed as well as developmental defects in the eye. These included microphthalmia, dysgenesis of the anterior segment of the eye, and abnormalities in retinal vessel architecture. Several data from animal and in vitro studies suggest that Pls may be involved in the regulation of retinal vascular development through the release of polyunsaturated fatty acids by a calcium-independent phospholipase A2.

  7. 18F-FDG and 68Ga-DOTATATE PET/CT in von Hippel-Lindau Disease-Associated Retinal Hemangioblastoma.

    Science.gov (United States)

    Papadakis, Georgios Z; Millo, Corina; Jassel, Inderbir S; Bagci, Ulas; Sadowski, Samira M; Karantanas, Apostolos H; Patronas, Nicholas J

    2017-03-01

    Retinal hemangioblastomas are highly vascular benign tumors that can be encountered either sporadically or within the von Hippel-Lindau (VHL) syndrome. We report a case of a VHL patient with retinal hemangioblastoma who underwent PET/CT scans using F-FDG and Ga-DOTATATE. The tumor showed low-level F-FDG and increased Ga-DOTATATE activity, suggesting cell-surface overexpression of somatostatin receptors. The presented case indicates the clinical applications of somatostatin receptor imaging with Ga-DOTA-conjugated peptides in detection and follow-up of VHL manifestations, screening of asymptomatic gene carriers, and in diagnosis of sporadic retinal hemangioblastomas, which may have similar features on MRI with other retinal tumors.

  8. The cell stress machinery and retinal degeneration.

    Science.gov (United States)

    Athanasiou, Dimitra; Aguilà, Monica; Bevilacqua, Dalila; Novoselov, Sergey S; Parfitt, David A; Cheetham, Michael E

    2013-06-27

    Retinal degenerations are a group of clinically and genetically heterogeneous disorders characterised by progressive loss of vision due to neurodegeneration. The retina is a highly specialised tissue with a unique architecture and maintaining homeostasis in all the different retinal cell types is crucial for healthy vision. The retina can be exposed to a variety of environmental insults and stress, including light-induced damage, oxidative stress and inherited mutations that can lead to protein misfolding. Within retinal cells there are different mechanisms to cope with disturbances in proteostasis, such as the heat shock response, the unfolded protein response and autophagy. In this review, we discuss the multiple responses of the retina to different types of stress involved in retinal degenerations, such as retinitis pigmentosa, age-related macular degeneration and glaucoma. Understanding the mechanisms that maintain and re-establish proteostasis in the retina is important for developing new therapeutic approaches to fight blindness.

  9. Prevalence of generalized retinal dystrophy in Denmark

    DEFF Research Database (Denmark)

    Bertelsen, Mette; Jensen, Hanne; Bregnhøj, Jesper F;

    2014-01-01

    of this study was to examine the prevalence and diagnostic spectrum of generalized retinal dystrophy in the Danish population. METHODS: A population-based cross-sectional study with data from the Danish Retinitis Pigmentosa Registry that comprises all patients in Denmark with generalized retinal....... RESULTS: Of the 5,602,628 Danish citizens on January 1, 2013, 1622 patients were registered as having a generalized retinal dystrophy and were alive and living in Denmark, corresponding to a prevalence of 1:3,454. In 28% of cases the eye condition was part of a syndrome, while the remaining 72% had eye...... disease only. Aside from simplex cases (45%), the most common hereditary pattern was autosomal recessive (23%). CONCLUSION: This epidemiological survey demonstrates that the prevalence of generalized retinal dystrophy in the Danish population is 1:3454. Many of the dystrophies are the subjects of clinical...

  10. Bilateral Progressive Obliterative Retinal Vasculitis

    Institute of Scientific and Technical Information of China (English)

    1994-01-01

    In this paper, 10 cases of a special type of retinal vasculitis are reported, which was characterized by progressive obliteration of vessels in both eyes, developed from the periphery to the posterior ploe, and was complicated by vitreous hemorrhage (5 eyes) and neovascular glaucoma (5 eyes) in later stage. The visual acuity was 0. 05 in 10 eyes (50%). Argon laser pho-tocoagulation seemed to be able to retard the natural course of the disease. Fundus changes, differential diagnosis and treatment etc are...

  11. Regenerative Therapy for Retinal Disorders

    Directory of Open Access Journals (Sweden)

    Narsis Daftarian

    2010-01-01

    Full Text Available Major advances in various disciplines of basic sciences including embryology, molecular and cell biology, genetics, and nanotechnology, as well as stem cell biology have opened new horizons for regenerative therapy. The unique characteristics of stem cells prompt a sound understanding for their use in modern regenerative therapies. This review article discusses stem cells, developmental stages of the eye field, eye field transcriptional factors, and endogenous and exogenous sources of stem cells. Recent studies and challenges in the application of stem cells for retinal pigment epithelial degeneration models will be summarized followed by obstacles facing regenerative therapy.

  12. Analysis by NASA's VESGEN Software of Retinal Blood Vessels Before and After 70-Day Bed Rest: A Retrospective Study

    Science.gov (United States)

    Raghunandan, Sneha; Vyas, Ruchi J.; Vizzeri, Gianmarco; Taibbi, Giovanni; Zanello, Susana B.; Ploutz-Snyder, Robert; Parsons-Wingerter, Patricia A.

    2016-01-01

    Significant risks for visual impairment associated with increased intracranial pressure (VIIP) are incurred by microgravity spaceflight, especially long-duration missions. Impairments include decreased near visual acuity, posterior globe flattening, choroidal folds, optic disc edema and cotton wool spots. We hypothesize that microgravity-induced fluid shifts result in pathological changes within the retinal blood vessels that precede development of visual and other ocular impairments. Potential contributions of retinal vascular remodeling to VIIP etiology are therefore being investigated by NASAs innovative VESsel GENeration Analysis (VESGEN) software for two studies: (1) head-down tilt in human subjects before and after 70 days of bed rest, and (2) U.S. crew members before and after ISS missions. VESGEN analysis in previous research supported by the US National Institutes of Health identified surprising new opportunities to regenerate retinal vessels during early-stage, potentially reversible progression of the visually impairing and blinding disease, diabetic retinopathy.

  13. Retinal Vessel Segmentation: A Comparative Study of Fuzzy C-means and Sum Entropy Information on Phase Congruency

    Directory of Open Access Journals (Sweden)

    Temitope Mapayi

    2015-09-01

    Full Text Available As the use of robotic-assisted surgery systems continue to increase, highly accurate and timely efficient automatic vasculature detection techniques for large and thin vessels in the retinal images are needed. Vascular segmentation has however been challenging due to uneven illumination in retinal images. The use of efficient pre-processing techniques as well as good segmentation techniques are highly needed to produce good vessel segmentation results. This paper presents an investigatory study on the combination of phase congruence with fuzzy c-means and the combination of phase congruence with gray level co-occurrence (GLCM matrix sum entropy for the segmentation of retinal vessels. Fuzzy C-Means combined with phase congruence yields a higher accuracy rate but a longer running time while compared to GLCM sum entropy combined with phase congruence. While compared with the widely previously used techniques on DRIVE and STARE databases, the techniques investigated yield high average accuracy rates.

  14. In-vivo imaging of blood flow in human retinal vessels using color Doppler optical coherence tomography

    Science.gov (United States)

    Yazdanfar, Siavash; Rollins, Andrew M.; Izatt, Joseph A.

    1999-04-01

    Quantification of retinal blood flow may lead to a better understanding of the progression and treatment of several ocular disorders, including diabetic retinopathy, age- related macular degeneration, and glaucoma. Current techniques, such as fluorescein angiography and laser Doppler velocimetry are limited, failing to provide sufficient information to the clinician. Color Doppler optical coherence tomography (CDOCT) is a novel technique using coherent heterodyne detection for simultaneous cross- sectional imaging of tissue microstructure and blood flow. This technique is capable of high spatial and velocity resolution imaging in highly scattering media. We implemented CDOCT for retinal blood flow mapping in human subjects. No dilation of the pupil was necessary. CDOCT is demonstrated for determining bidirectional flow in sub- 100micrometers diameter vessels in the retina. Additionally, we calculated Doppler broadening using the variance of depth- resolved spectra to identify regions with large velocity gradients within the Xenopus heart. This technique may be useful in quantifying local tissue perfusion in highly vascular retinal tissue.

  15. Retinal vein occlusion and macular edema – critical evaluation of the clinical value of ranibizumab

    Directory of Open Access Journals (Sweden)

    Keane PA

    2011-06-01

    Full Text Available Pearse A Keane1, Srinivas R Sadda21NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, UK; 2Doheny Eye Institute, Keck School of Medicine of the University of Southern California, Los Angeles, CA, USAAbstract: Retinal vein occlusions (RVOs constitute the second most common cause of retinal vascular disease after diabetic retinopathy, with a prevalence of between 1% and 2% in persons older than 40 years of age. Despite the existence of numerous potential therapeutic options, none is entirely satisfactory, and many patients with RVO suffer irreversible visual loss. Fortunately however, the recent introduction of antivascular endothelial growth factor (VEGF agents, such as ranibizumab (Lucentis®, Genentech, South San Francisco, CA and bevacizumab (Avastin®, Genentech, offers a potentially new treatment approach for clinicians managing this disorder. The results of the BRAVO and CRUISE trials have provided the first definitive evidence for the efficacy and safety of ranibizumab in the treatment of RVO. As a result, ranibizumab has recently been approved by the US Food and Drug Administration for the treatment of RVO-associated macular edema. In this review, we provide a critical evaluation of clinical trial data for the safety and efficacy of ranibizumab, and address unresolved issues in the management of this disorder. Keywords: ranibizumab, retinal vein occlusion, vascular endothelial growth factor, macular edema

  16. Improvement in Retinal Capillary Rarefaction After Valsartan Treatment in Hypertensive Patients.

    Science.gov (United States)

    Jumar, Agnes; Harazny, Joanna M; Ott, Christian; Kistner, Iris; Friedrich, Stefanie; Schmieder, Roland E

    2016-11-01

    Decreased capillary density influences vascular resistance and perfusion. The authors aimed to investigate the influence of the renin-angiotensin receptor blocker valsartan on retinal capillary rarefaction in hypertensive patients. Retinal vascular parameters were measured noninvasively and in vivo by scanning laser Doppler flowmetry before and after 4 weeks of treatment with valsartan in 95 patients with hypertension stage 1 or 2 and compared with 55 healthy individuals. Retinal capillary rarefaction was determined with the parameters intercapillary distance (ICD) and capillary area (CapA). In hypertensive patients, ICD decreased (23.4±5.5 μm vs 21.5±5.6 μm, PCapA increased (1564±621 vs 1776±795, P=.001) after valsartan treatment compared with baseline. Compared with healthy normotensive controls (ICD 20.2±4.2 μm, CapA 1821±652), untreated hypertensive patients showed greater ICD (PCapA (P=.019), whereas treated hypertensive patients showed no difference in ICD (P=.126) and CapA (P=.728). Therapy with valsartan for 4 weeks diminished capillary rarefaction in hypertensive patients.

  17. RP1L1 variants are associated with a spectrum of inherited retinal diseases including retinitis pigmentosa and occult macular dystrophy.

    Science.gov (United States)

    Davidson, Alice E; Sergouniotis, Panagiotis I; Mackay, Donna S; Wright, Genevieve A; Waseem, Naushin H; Michaelides, Michel; Holder, Graham E; Robson, Anthony G; Moore, Anthony T; Plagnol, Vincent; Webster, Andrew R

    2013-03-01

    In one consanguineous family with retinitis pigmentosa (RP), a condition characterized by progressive visual loss due to retinal degeneration, homozygosity mapping, and candidate gene sequencing suggested a novel locus. Exome sequencing identified a homozygous frameshifting mutation, c.601delG, p.Lys203Argfs*28, in RP1L1 encoding RP 1-like1, a photoreceptor-specific protein. A screen of a further 285 unrelated individuals with autosomal recessive RP identified an additional proband, homozygous for a missense variant, c.1637G>C, p.Ser546Thr, in RP1L1. A distinct retinal disorder, occult macular dystrophy (OCMD) solely affects the central retinal cone photoreceptors and has previously been reported to be associated with variants in the same gene. The association between mutations in RP1L1 and the disorder OCMD was explored by screening a cohort of 28 unrelated individuals with the condition; 10 were found to harbor rare (minor allele frequency ≤0.5% in the 1,000 genomes dataset) heterozygous RP1L1 missense variants. Analysis of family members revealed many unaffected relatives harboring the same variant. Linkage analysis excluded the possibility of a recessive mode of inheritance, and sequencing of RP1, a photoreceptor protein that interacts with RP1L1, excluded a digenic mechanism involving this gene. These findings imply an important and diverse role for RP1L1 in human retinal physiology and disease.

  18. Intravenously administered gold nanoparticles pass through the blood-retinal barrier depending on the particle size, and induce no retinal toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jeong Hun; Kim, Jin Hyoung; Yu, Young Suk [Department of Ophthalmology, Seoul National University College of Medicine and Seoul Artificial Eye Center, Clinical Research Institute, Seoul National University Hospital, Seoul 151744 (Korea, Republic of); Kim, Kyu-Won [NeuroVascular Coordination Research Center, College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 151742 (Korea, Republic of); Kim, Myung Hun, E-mail: hunin315@paran.com, E-mail: ysyu@snu.ac.kr [Department of Chemistry, Yonsei University, 134 Shinchon-dong, Seodaemun-ku, Seoul 120749 (Korea, Republic of)

    2009-12-16

    The retina maintains homeostasis through the blood-retinal barrier (BRB). Although it is ideal to deliver the drug to the retina via systemic administration, it is still challenging due to the BRB strictly regulating permeation from blood to the retina. Herein, we demonstrated that intravenously administered gold nanoparticles could pass through the BRB and are distributed in all retinal layers without cytotoxicity. After intravenous injection of gold nanoparticles into C57BL/6 mice, 100 nm nanoparticles were not detected in the retina whereas 20 nm nanoparticles passed through the BRB and were distributed in all retinal layers. 20 nm nanoparticles in the retina were observed in neurons (75 {+-} 5%), endothelial cells (17 {+-} 6%) and peri-endothelial glial cells (8 {+-} 3%), where nanoparticles were bound on the membrane. In the retina, cells containing nanoparticles did not show any structural abnormality and increase of cell death compared to cells without nanoparticles. Gold nanoparticles never affected the viability of retinal endothelial cells, astrocytes and retinoblastoma cells. Furthermore, gold nanoparticles never led to any change in expression of representative biological molecules including zonula occludens-1 and glut-1 in retinal endothelial cells, neurofilaments in differentiated retinoblastoma cells and glial fibrillary acidic protein in astrocytes. Therefore, our data suggests that small gold nanoparticles (20 nm) could be an alternative for drug delivery across the BRB, which could be safely applied in vivo.

  19. A partial intensity invariant feature descriptor for multimodal retinal image registration.

    Science.gov (United States)

    Chen, Jian; Tian, Jie; Lee, Noah; Zheng, Jian; Smith, R Theodore; Laine, Andrew F

    2010-07-01

    Detection of vascular bifurcations is a challenging task in multimodal retinal image registration. Existing algorithms based on bifurcations usually fail in correctly aligning poor quality retinal image pairs. To solve this problem, we propose a novel highly distinctive local feature descriptor named partial intensity invariant feature descriptor (PIIFD) and describe a robust automatic retinal image registration framework named Harris-PIIFD. PIIFD is invariant to image rotation, partially invariant to image intensity, affine transformation, and viewpoint/perspective change. Our Harris-PIIFD framework consists of four steps. First, corner points are used as control point candidates instead of bifurcations since corner points are sufficient and uniformly distributed across the image domain. Second, PIIFDs are extracted for all corner points, and a bilateral matching technique is applied to identify corresponding PIIFDs matches between image pairs. Third, incorrect matches are removed and inaccurate matches are refined. Finally, an adaptive transformation is used to register the image pairs. PIIFD is so distinctive that it can be correctly identified even in nonvascular areas. When tested on 168 pairs of multimodal retinal images, the Harris-PIIFD far outperforms existing algorithms in terms of robustness, accuracy, and computational efficiency.

  20. Retinal neurodegeneration may precede microvascular changes characteristic of diabetic retinopathy in diabetes mellitus.

    Science.gov (United States)

    Sohn, Elliott H; van Dijk, Hille W; Jiao, Chunhua; Kok, Pauline H B; Jeong, Woojin; Demirkaya, Nazli; Garmager, Allison; Wit, Ferdinand; Kucukevcilioglu, Murat; van Velthoven, Mirjam E J; DeVries, J Hans; Mullins, Robert F; Kuehn, Markus H; Schlingemann, Reinier Otto; Sonka, Milan; Verbraak, Frank D; Abràmoff, Michael David

    2016-05-10

    Diabetic retinopathy (DR) has long been recognized as a microvasculopathy, but retinal diabetic neuropathy (RDN), characterized by inner retinal neurodegeneration, also occurs in people with diabetes mellitus (DM). We report that in 45 people with DM and no to minimal DR there was significant, progressive loss of the nerve fiber layer (NFL) (0.25 μm/y) and the ganglion cell (GC)/inner plexiform layer (0.29 μm/y) on optical coherence tomography analysis (OCT) over a 4-y period, independent of glycated hemoglobin, age, and sex. The NFL was significantly thinner (17.3 μm) in the eyes of six donors with DM than in the eyes of six similarly aged control donors (30.4 μm), although retinal capillary density did not differ in the two groups. We confirmed significant, progressive inner retinal thinning in streptozotocin-induced "type 1" and B6.BKS(D)-Lepr(db)/J "type 2" diabetic mouse models on OCT; immunohistochemistry in type 1 mice showed GC loss but no difference in pericyte density or acellular capillaries. The results suggest that RDN may precede the established clinical and morphometric vascular changes caused by DM and represent a paradigm shift in our understanding of ocular diabetic complications.

  1. Swept-source OCT Angiography of the Retinal Vasculature using Intensity Differentiation Based OMAG Algorithms

    Science.gov (United States)

    Huang, Yanping; Zhang, Qinqin; Thorell, Mariana Rossi; An, Lin; Durbin, Mary; Laron, Michal; Sharma, Utkarsh; Gregori, Giovanni; Rosenfeld, Philip J.; Wang, Ruikang K

    2014-01-01

    Background and Objective To demonstrate the feasibility of using a 1050 nm swept-source OCT (SS-OCT) system to achieve noninvasive retinal vasculature imaging in human eyes. Materials and Methods Volumetric datasets were acquired using a ZEISS 1 µm SS-OCT prototype that operated at an A-line rate of 100 kHz. A scanning protocol designed to allow for motion contrast processing, referred to as OCT angiography or optical microangiography (OMAG), was used to scan ~3 mm × 3 mm area in the central macular region of the retina within ~4.5 seconds. Intensity differentiation based OMAG algorithm was used to extract 3-D retinal functional microvasculature information. Results Intensity signal differentiation generated capillary-level resolution en face OMAG images of the retina. The parafoveal capillaries were clearly visible, thereby allowing visualization of the foveal avascular zone (FAZ) in normal subjects. Conclusion The capability of OMAG to produce retinal vascular images was demonstrated using the ZEISS 1 µm SS-OCT prototype. This technique can potentially have clinical value for studying retinal vasculature abnormalities. PMID:25230403

  2. Central retinal artery resistive index and optical coherence tomography in assessment of glaucoma progression

    Institute of Scientific and Technical Information of China (English)

    Ahmed; F.Abdel; Ghany; Samer; M.Botros; Tamer; M.El-Raggal

    2015-01-01

    AIM: To assess the relation between central retinal artery(CRA) resistive index(RI) and retinal nerve fiber thickness measured by optical coherence tomography(OCT) in assessment of disease progress in cases of open angle glaucoma.METHODS: Twenty-three patients with diagnosed open angle glaucoma were included in this study. They were examined by colored duplex ultrasonography of CRA with estimation of RI of CRA and ophthalmic artery(OA)with estimation of CRA/OA RI ratio as well as OCT measurement of the average retinal nerve fiber layer(RNFL) thickness in order to assess the disease progress.RESULTS: There was strong inverse relation between the increased RI in CRA as well as the increased CRA/OA RI ratio and the decrease in average RNFL thickness in cases of open angle glaucoma.CONCLUSION: Assessment of CRA RI can indirectly assess the vascular changes associated with glaucoma and can assess the degree of retinal atrophy helping in evaluating prognosis thus guiding the choice of treatment.

  3. Retinal angiography with real-time speckle variance optical coherence tomography.

    Science.gov (United States)

    Xu, Jing; Han, Sherry; Balaratnasingam, Chandrakumar; Mammo, Zaid; Wong, Kevin S K; Lee, Sieun; Cua, Michelle; Young, Mei; Kirker, Andrew; Albiani, David; Forooghian, Farzin; Mackenzie, Paul; Merkur, Andrew; Yu, Dao-Yi; Sarunic, Marinko V

    2015-10-01

    This report describes a novel, non-invasive and label-free optical imaging technique, speckle variance optical coherence tomography (svOCT), for visualising blood flow within human retinal capillary networks. This imaging system uses a custom-built swept source OCT system operating at a line rate of 100 kHz. Real-time processing and visualisation is implemented on a consumer grade graphics processing unit. To investigate the quality of microvascular detail acquired with this device we compared images of human capillary networks acquired with svOCT and fluorescein angiography. We found that the density of capillary microvasculature acquired with this svOCT device was visibly greater than fluorescein angiography. We also found that this svOCT device had the capacity to generate en face images of distinct capillary networks that are morphologically comparable with previously published histological studies. Finally, we found that this svOCT device has the ability to non-invasively illustrate the common manifestations of diabetic retinopathy and retinal vascular occlusion. The results of this study suggest that graphics processing unit accelerated svOCT has the potential to non-invasively provide useful quantitative information about human retinal capillary networks. Therefore svOCT may have clinical and research applications for the management of retinal microvascular diseases, which are a major cause of visual morbidity worldwide.

  4. No evidence for thrombophilia in patients with retinal venous occlusion: a systematic GRADE-based review.

    Science.gov (United States)

    Kirkegaard, Kirstine; Heegaard, Steffen; Hvas, Anne-Mette

    2017-02-01

    Retinal venous occlusion represents a common retinal disorder that untreated often leads to severely reduced vision. While general risk factors for vascular disease are known to increase the risk of an event, the role of thrombophilia is controversial. The purpose of this systematic review was to evaluate the evidence for thrombophilia investigation in patients presenting with retinal venous occlusion. Eligible studies were identified by a MESH-based search in PubMed 11-13 of March 2015. The level of evidence was stated according to the guidelines published by the GRADE working group using three levels for quality of evidence: high, moderate and low. A total of 118 studies relating to the study question were identified. After excluding case stories, commentaries, cross-sectional studies and reviews/expert opinions, 28 original papers and two meta-analyses were included in the final qualitative synthesis. The majority of studies were small case-control studies, and only one large cohort study was identified. No randomized controlled trials were retrieved. All the studies were categorized as low quality of evidence. Systematic thrombophilia screening in patients presenting with retinal venous occlusion cannot be recommended.

  5. Bone marrow-derived cells are differentially involved in pathological and physiological retinal angiogenesis in mice

    Energy Technology Data Exchange (ETDEWEB)

    Zou, He [Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto 606-8507 (Japan); Otani, Atsushi, E-mail: otan@kuhp.kyoto-u.ac.jp [Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto 606-8507 (Japan); Oishi, Akio; Yodoi, Yuko; Kameda, Takanori; Kojima, Hiroshi; Yoshimura, Nagahisa [Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto 606-8507 (Japan)

    2010-01-08

    Purpose: Bone marrow-derived cells have been shown to play roles in angiogenesis. Although these cells have been shown to promote angiogenesis, it is not yet clear whether these cells affect all types of angiogenesis. This study investigated the involvement of bone marrow-derived cells in pathological and physiological angiogenesis in the murine retina. Materials and methods: The oxygen-induced retinopathy (OIR) model was used as a retinal angiogenesis model in newborn mice. To block the influence of bone marrow-derived cells, the mice were irradiated with a 4-Gy dose of radiation from a {sup 137}Cs source. Irradiation was performed in four different conditions with radio dense 2-cm thick lead disks; (1) H group, the head were covered with these discs to protect the eyes from radiation; (2) A group, all of the body was covered with these discs; (3) N group, mice were completely unshielded; (4) C group, mice were put in the irradiator but were not irradiated. On P17, the retinal areas showing pathological and physiological retinal angiogenesis were measured and compared to the retinas of nonirradiated mice. Results: Although irradiation induced leukocyte depletion, it did not affect the number of other cell types or body weight. Retinal nonperfusion areas were significantly larger in irradiated mice than in control mice (P < 0.05), indicating that physiological angiogenesis was impaired. However, the formation of tuft-like angiogenesis processes was more prominent in the irradiated mice (P < 0.05), indicating that pathological angiogenesis was intact. Conclusions: Bone marrow-derived cells seem to be differentially involved in the formation of physiological and pathological retinal vessels. Pathological angiogenesis in the murine retina does not require functional bone marrow-derived cells, but these cells are important for the formation of physiological vessels. Our results add a new insight into the pathology of retinal angiogenesis and bolster the hypothesis that

  6. Preparation and features of polycaprolactone vascular grafts with the incorporated vascular endothelial growth factor

    Energy Technology Data Exchange (ETDEWEB)

    Sevostyanova, V. V., E-mail: sevostyanova.victoria@gmail.com; Khodyrevskaya, Y. I.; Glushkova, T. V.; Antonova, L. V.; Kudryavtseva, Y. A.; Barbarash, O. L.; Barbarash, L. S. [Research Institute for Complex Issues of Cardiovascular Diseases, Kemerovo (Russian Federation)

    2015-10-27

    The development of tissue-engineered small-diameter vascular grafts is an urgent issue in cardiovascular surgery. In this study, we assessed how the incorporation of the vascular endothelial growth factor (VEGF) affects morphological and mechanical properties of polycaprolactone (PCL) vascular grafts along with its release kinetics. Vascular grafts were prepared using two-phase electrospinning. In pursuing our aims, we performed scanning electron microscopy, mechanical testing, and enzyme-linked immunosorbent assay. Our results demonstrated the preservation of a highly porous structure and improvement of PCL/VEGF scaffold mechanical properties as compared to PCL grafts. A prolonged VEGF release testifies the use of this construct as a scaffold for tissue-engineered vascular grafts.

  7. Novel mutations in two Saudi patients with congenital retinal dystrophy

    Directory of Open Access Journals (Sweden)

    Leen Abu Safieh

    2016-01-01

    Full Text Available To report novel mutations in two Saudi children with clinical features of Leber congenital amaurosis (LCA and Alström syndrome. Case reports. Case 1 was a child with phenotypic features of LCA including oculodigital sign, bilateral enophthalmos, nystagmus, pale disc, and retinal changes. Direct sequencing of the coding sequence of GUCY2D revealed a missense mutation affecting highly conserved position (c. 743C > T; p.S248 L. Case 2 describes a girl with marked nystagmus, photophobia, and retinal changes in both eyes with short and stubby fingers tapering at the distal phalanges. The electroretinograms were nonrecordable in each eye. She had a hearing aid in the left ear, mid-facial hypoplasia, bilateral enophthalmos, and insulin dependent diabetes. Mutation screening of candidates genes revealed a pathogenic mutation in ALMS1 gene (c. 8441C > A, p.S2814*. Two novel mutations causing phenotypic LCA and Alström syndrome in Saudi patients from consanguineous families expand the genotypic spectrum of congenital retinal dystrophies

  8. An Ocular Protein Triad Can Classify Four Complex Retinal Diseases

    Science.gov (United States)

    Kuiper, J. J. W.; Beretta, L.; Nierkens, S.; van Leeuwen, R.; Ten Dam-van Loon, N. H.; Ossewaarde-van Norel, J.; Bartels, M. C.; de Groot-Mijnes, J. D. F.; Schellekens, P.; de Boer, J. H.; Radstake, T. R. D. J.

    2017-01-01

    Retinal diseases generally are vision-threatening conditions that warrant appropriate clinical decision-making which currently solely dependents upon extensive clinical screening by specialized ophthalmologists. In the era where molecular assessment has improved dramatically, we aimed at the identification of biomarkers in 175 ocular fluids to classify four archetypical ocular conditions affecting the retina (age-related macular degeneration, idiopathic non-infectious uveitis, primary vitreoretinal lymphoma, and rhegmatogenous retinal detachment) with one single test. Unsupervised clustering of ocular proteins revealed a classification strikingly similar to the clinical phenotypes of each disease group studied. We developed and independently validated a parsimonious model based merely on three proteins; interleukin (IL)-10, IL-21, and angiotensin converting enzyme (ACE) that could correctly classify patients with an overall accuracy, sensitivity and specificity of respectively, 86.7%, 79.4% and 92.5%. Here, we provide proof-of-concept for molecular profiling as a diagnostic aid for ophthalmologists in the care for patients with retinal conditions.

  9. An Ocular Protein Triad Can Classify Four Complex Retinal Diseases

    Science.gov (United States)

    Kuiper, J. J. W.; Beretta, L.; Nierkens, S.; van Leeuwen, R.; ten Dam-van Loon, N. H.; Ossewaarde-van Norel, J.; Bartels, M. C.; de Groot-Mijnes, J. D. F.; Schellekens, P.; de Boer, J. H.; Radstake, T. R. D. J.

    2017-01-01

    Retinal diseases generally are vision-threatening conditions that warrant appropriate clinical decision-making which currently solely dependents upon extensive clinical screening by specialized ophthalmologists. In the era where molecular assessment has improved dramatically, we aimed at the identification of biomarkers in 175 ocular fluids to classify four archetypical ocular conditions affecting the retina (age-related macular degeneration, idiopathic non-infectious uveitis, primary vitreoretinal lymphoma, and rhegmatogenous retinal detachment) with one single test. Unsupervised clustering of ocular proteins revealed a classification strikingly similar to the clinical phenotypes of each disease group studied. We developed and independently validated a parsimonious model based merely on three proteins; interleukin (IL)-10, IL-21, and angiotensin converting enzyme (ACE) that could correctly classify patients with an overall accuracy, sensitivity and specificity of respectively, 86.7%, 79.4% and 92.5%. Here, we provide proof-of-concept for molecular profiling as a diagnostic aid for ophthalmologists in the care for patients with retinal conditions. PMID:28128370

  10. PHAKOMATOSIS : INTRESTING CASES OF TUBEROUS SCLEROSIS WITH RETINAL ASTROCYTOMA

    Directory of Open Access Journals (Sweden)

    Srinivasa Rao

    2015-05-01

    Full Text Available NTRODUCTION: Tuberous sclerosis complex (TSC or Morbus Bourneville - Pringle disease is an autosomal dominant phakomatosis, first described by Desiree - Magloire Bourneville in 1880. Tuberous sclerosis is a genetic disorder characterized by the growth of numerous benign tumours in many parts of the body caused by mutations on either of two genes, TSC1 and TSC2. This rare genetic disorder is usually associated with a triad of seizures, mental retardation and cutaneous lesions. Approximately one half of all patients affected by TS develop at least one retinal astrocytoma in one eye. PRESENTATION OF CASES: In the department of ophthalmology, G.S.L M edical C ollege, Rajahmundry, we came across 3 cases of tuberous sclerosis involving multi organ systems. Out of 3 cases, 2 cases were reported to be familial and 1case is sporadic, with a history of epilepsy with angiofibromatosis lesions over the face, multiple ash - leaf lesions over the abdomen, renal angiomyolipomas, multiple subependymal nodules in brain and retinal astrocytic hamartomas in the retina. CONCLUSION: It is important to be cognizant of the likely presence of systemic and ocular pathology in a child with mental retardation and skin lesions. Identification of retinal phakomatosis during ocular evaluation in any suspected case of Tuberous sclerosis can aid in the establishment of the diagnosis of the disease

  11. Effect of vascular burden as measured by vascular indexes upon vascular dementia: a matched case-control study

    Directory of Open Access Journals (Sweden)

    Takahashi PY

    2012-01-01

    Full Text Available Paul Y Takahashi, Casey R Caldwell, Paul V TargonskiPrimary Care Internal Medicine, Mayo Clinic, Rochester MN, USABackground: Vascular dementia (VaD is a challenging illness that affects the lives of older adults and caregivers. It is unclear how multiple vascular risk factor exposures (polyvascular disease affect VaD.Purpose: To determine the relationship between multiple vascular risk exposures, as counted on an index in cases with VaD, compared with healthy age-/gender-matched controls.Methods: This was a matched case-control study of subjects living in Olmsted County, MN with documented VaD. Controls were selected by gender and age within 3 years from those who did not have dementia. The exposures included a total index (eleven exposure factors added together, along with indexes for cerebrovascular disease (two exposures, cardiovascular disease (four exposures, vascular disease (three exposures, and lifestyle (two exposures. Analysis used matched conditional univariable logistic regression for each index.Results: A total of 1736 potential subjects were identified, and 205 subjects were diagnosed with VaD. There was a significant association of the total score index with an odds ratio of 1.45 (95% confidence interval 1.21–1.74. The cerebrovascular index was also associated with VaD with an odds ratio of 12.18 (95% confidence interval 6.29–23.61. The cardiovascular and vascular indexes were also associated with VaD status. The lifestyle index was not associated with VaD.Conclusion: The cumulative role of multiple vascular risk factors or diseases increased the risk of VaD, as noted by the total vascular index. The lifestyle index did not reveal any significant differences. Further work is required for evaluation of these indexes.Keywords: polyvascular disease, elderly, vascular dementia

  12. Effect of Axial Eye Length on Retinal Vessel Parameters in 6 to 12-Year-Old Malay Girls

    Science.gov (United States)

    Tai, Evelyn Li Min; Li, Ling-Jun; Wan-Hazabbah, Wan Hitam; Wong, Tien-Yin; Shatriah, Ismail

    2017-01-01

    Purpose Retinal vessel analysis is affected by both systemic and ocular factors. Malays are the major ethnicity in South East Asia. Data on the retinal microvasculature in Malays is limited, especially among children. We aim to evaluate the influence of ocular biometry on retinal vessel parameters in young Malay girls. Methods This was a cross-sectional, hospital-based study involving 86 Malay girls aged 6 to 12 years old in Hospital Universiti Sains Malaysia from 2015–2016. Ocular examination, refraction, biometry, retinal photography, and anthropometric measurements were performed. The central retinal arteriolar equivalent (CRAE), central retinal venular equivalent (CRVE) and overall fractal dimension (Df) were measured using validated computer-based methods (Singapore I vessel analyzer, SIVA version 3.0, Singapore). The associations of ocular biometry and CRAE, CRVE and Df were analyzed using multivariable analysis. Results The mean CRAE, CRVE and Df in Malay girls were 171.40 (14.40) um, 248.02 (16.95) um and 1.42 (0.05) respectively. Each 1 mm increase in axial length was associated with a reduction of 4.25 um in the CRAE (p = 0.03) and a reduction of 0.02 in the Df (p = 0.02), after adjustment for age, blood pressure and body mass index. No association was observed between axial length and CRVE. Anterior chamber depth and corneal curvature had no association with CRAE, CRVE or Df. Conclusion Axial length affects retinal vessel measurements. Narrower retinal arterioles and reduced retinal fractal dimension were observed in Malay girls with longer axial lengths. PMID:28107389

  13. Insight into 144 patients with ocular vascular events during VEGF antagonist injections

    Directory of Open Access Journals (Sweden)

    Shami M

    2012-03-01

    Full Text Available Ahmad M Mansour1, Maha Shahin2, Peter K Kofoed3, Maurizio B Parodi4, Michel Shami5, Stephen G Schwartz6, Collaborative Anti-VEGF Ocular Vascular Complications GroupDepartment of Ophthalmology, 1American University of Beirut, Beirut, Lebanon, Rafic Hariri University Hospital, Beirut, Lebanon; 2Mansoura University, Mansoura City, Egypt; 3Glostrup Hospital, University of Copenhagen, Denmark, National Eye Clinic, Kennedy Center, Glostrup, Denmark; 4University Vita-Salute, Scientific Institute San Raffaele, Milan, Italy; 5Texas Tech University Health Sciences Center, Lubbock, TX, USA; 6Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Naples and Miami, FL, USAAim: To record ocular vascular events following injections of vascular endothelium growth factor (VEGF antagonists.Methods: Collaborative multicenter case series (48 cases, literature reviews (32 cases, and reports to the FDA (64 cases of patients that had vascular occlusions during anti-VEGF therapy were collected and analyzed.Results: A total of 144 cases of ocular vascular events were identified, with these diagnosed a median of 15 days after anti-VEGF injection. The majority of patients had pre-existing risk factors for cardiovascular events and nine patients had a prior history of glaucoma. Mean visual acuity dropped by 6.4 lines with severe visual loss after injection to NLP (five eyes, LP (six eyes, and HM (two eyes. The overall risk of ocular vascular events following a VEGF antagonist injection was 0.108% in the general population and 2.61% in the diabetic population. Mean retinal arterial constriction after intravitreal bevacizumab in 13 eyes was 21% (standard deviation = 27%, and mean retinal venous constriction was 8% (standard deviation = 30%.Conclusion: Ocular vascular events are rare during anti-VEGF therapy, but can lead to severe visual loss and may be caused by a number of factors including the vasoconstrictor effect of the drug, a post-injection rise

  14. Demarcation laser photocoagulation induced retinal necrosis and rupture resulting in large retinal tear formation.

    Science.gov (United States)

    Quezada, Carlos; Pieramici, Dante J; Matsui, Rodrigo; Rabena, Melvin; Graue, Federico

    2015-06-01

    Retinal tears after laser photocoagulation are a rare complication that occurs after intense laser. It is talked about among retina specialist occurring particularly at the end of a surgical case while applying endophotocoagulation; to the best our knowledge, there are no reports in the literature of a large retinal tear induced after attempted in-office demarcation laser photocoagulation (DLP) that simulated a giant retinal tear. DLP has been employed in the management of selected cases of macula sparring rhegmatogenous retinal detachment (RRD). Even though extension of the retinal detachment through the "laser barrier" is considered a failure of treatment, few complications have been described with the use of this less invasive retinal detachment repair technique. We describe a case of a high myopic woman who initially was treated with demarcation laser photocoagulation for an asymptomatic retinal detachment associated with a single horseshoe tear and a full thickness large retinal tear was created where the laser was placed. Intense laser photocoagulation resulted in abrupt laser induced retinal necrosis and rupture creating this large retinal break. Proper laser technique should reduce the risks associated with this procedure.

  15. Functional and Molecular Characterization of Rod-like Cells from Retinal Stem Cells Derived from the Adult Ciliary Epithelium

    OpenAIRE

    Gian Carlo Demontis; Claudia Aruta; Antonella Comitato; Anna De Marzo; Valeria Marigo

    2012-01-01

    In vitro generation of photoreceptors from stem cells is of great interest for the development of regenerative medicine approaches for patients affected by retinal degeneration and for high throughput drug screens for these diseases. In this study, we show unprecedented high percentages of rod-fated cells from retinal stem cells of the adult ciliary epithelium. Molecular characterization of rod-like cells demonstrates that they lose ciliary epithelial characteristics but acquire photoreceptor...

  16. Molecular signal transduction in vascular cell apoptosis

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Apoptosis is a form of genetically programmed cell death, which plays a key role in regulation of cellularity in a variety of tissue and cell types including the cardiovascular tissues. Under both physiological and pathophysiological conditions, various biophysiological and biochemical factors, including mechanical forces, reactive oxygen and nitrogen species, cytokines, growth factors, oxidized lipoproteins, etc., may influence apoptosis of vascular cells. The Fas/Fas ligand/caspase death-signaling pathway, Bcl-2 protein family/mitochondria, the tumor suppressive gene p53, and the proto-oncogene c-myc may be activated in atherosclerotic lesions, and mediates vascular apoptosis during the development of atherosclerosis. Abnormal expression and dysfunction of these apoptosis-regulating genes may attenuate or accelerate vascular cell apoptosis and affect the integrity and stability of atherosclerotic plaques. Clarification of the molecular mechanism that regulates apoptosis may help design a new strategy for treatment of atherosclerosis and its major complication, the acute vascular syndromes.

  17. Ultra-high resolution profiles of macular intra-retinal layer thicknesses and associations with visual field defects in primary open angle glaucoma

    Science.gov (United States)

    Chen, Qi; Huang, Shenghai; Ma, Qingkai; Lin, Huiling; Pan, Mengmeng; Liu, Xinting; Lu, Fan; Shen, Meixiao

    2017-01-01

    The structural characteristics of the outer retinal layers in primary open angle glaucoma (POAG) are still controversial, and these changes, along with those in the inner retinal layers, could have clinical and/or pathophysiological significance. A custom-built ultra-high resolution optical coherence tomography (UHR-OCT) combined with an automated segmentation algorithm can image and measure the eight intra-retinal layers. The purpose of this study is to determine the thickness characteristics of the macular intra-retinal layers, especially the outer layers, in POAG patients. Thirty-four POAG patients (56 eyes) and 33 normal subjects (63 eyes) were enrolled. Thickness profiles of the eight intra-retinal layers along a 6-mm length centred on the fovea at the horizontal and vertical meridians were obtained and the regional thicknesses were compared between two groups. The associations between the thicknesses of each intra-retinal layer and the macular visual field (VF) sensitivity were then analysed. POAG affected not only the inner retinal layers but also the photoreceptor layers and retinal pigment epithelium of the outer retina. However, the VF loss was correlated mainly with the damage of the inner retinal layers. UHR-OCT with automated algorithm is a useful tool in detecting microstructural changes of macula with respect to the progression of glaucoma. PMID:28169283

  18. [Sex steroids and vascular risk].

    Science.gov (United States)

    Rozenbaum, H

    1983-01-01

    The chemical diversity of estrogen and progestogen components of oral contraceptive (OC) products, their use alone or in combination, and the diversity of treatment regimens and doses account for the majority of contradictions in the immense literature on vascular and metabolic side effects of these hormones. OCs are exclusively composed of synthetic hormones. All OCs impose metabolic modifications on the organism and especially on the hepatic parenchyma due to delayed hepatic degradation. Certain factors increase the risk of vascular accidents associated with OC use: metabolic changes affecting coagulation, lipids, glucides, and arterial hypertension, immunologic phenomena, smoking, and obesity. As a whole, OCs affect coagulation by elevating factors 7 and 10, decreasing antithrombin iii (in high doses), and decreasing plasma fibrinolytic activity. synthetic estrogens cause an elevation of HDL cholesterol, a slight elevation of phospholipids, and a dose-dependent elevation of triglycerides and their VLDL fraction. As a group, progestogens tend to decrease the HDL fraction of cholesterol. Norethindrone is incapable of opposing the hypertriglyceridemic action of synthtic estrogens, while norgestrel partially opposes it. Lipid modifications provoked by combined OCs are a function of the nature and dosage of the components. Among hemodynamic modifications, synthetic estrogens cause elevations in renin substrate, plasma renin activity, angiotensin 2 and aldosterone. Synthetic progestogens may have various effects depending on type and dose, but they do not appear sufficient to cause hypertension unless other factors linked to individual predispositions are present. Microdoses of progestogens alone do not affect the renin-angiotensin-aldosterone system. Studies have also been conducted on the effect of OCs on cardiac function and on the vascular walls. Prospective studies suggest a relative risk of 3 for venous thromboembolic accidents among OC users, while

  19. Poikiloderma vasculare atrophicans

    Directory of Open Access Journals (Sweden)

    Padmavathy L

    1994-01-01

    Full Text Available A 65 year old lady presented with generalised pruritus and discolouration of skin and mucous membranes of 5 years duration. The histopathology from the cutaneous lesions revealed features suggestive of poikiloderma vasculare atrophicans (PVA. Investigations did not reveal any underlying connective tissue disease,lymphoma or systemic disease. A diagnosis of idiopathic poikiloderma vasculare atrophicans was made.

  20. [Vascular factors in glaucoma].

    Science.gov (United States)

    Mottet, B; Aptel, F; Geiser, M; Romanet, J P; Chiquet, C

    2015-12-01

    The exact pathophysiology of glaucoma is not fully understood. Understanding of the vascular pathophysiology of glaucoma requires: knowing the techniques for measuring ocular blood flow and characterizing the topography of vascular disease and the mechanisms involved in this neuropathy. A decreased mean ocular perfusion pressure and a loss of vascular autoregulation are implicated in glaucomatous disease. Early decrease in ocular blood flow has been identified in primary open-angle glaucoma and normal pressure glaucoma, contributing to the progression of optic neuropathy. The vascular damage associated with glaucoma is present in various vascular territories within the eye (from the ophthalmic artery to the retina) and is characterized by a decrease in basal blood flow associated with a dysfunction of vasoregulation.

  1. Antagonism of CD11b with neutrophil inhibitory factor (NIF inhibits vascular lesions in diabetic retinopathy.

    Directory of Open Access Journals (Sweden)

    Alexander A Veenstra

    Full Text Available Leukocytes and proteins that govern leukocyte adhesion to endothelial cells play a causal role in retinal abnormalities characteristic of the early stages of diabetic retinopathy, including diabetes-induced degeneration of retinal capillaries. Leukocyte integrin αmβ2 (CD11b/CD18, MAC1, a protein mediating adhesion, has been shown to mediate damage to endothelial cells by activated leukocytes in vitro. We hypothesized that Neutrophil Inhibitory Factor (NIF, a selective antagonist of integrin αmβ2, would inhibit the diabetes-induced degeneration of retinal capillaries by inhibiting the excessive interaction between leukocytes and retinal endothelial cells in diabetes. Wild type animals and transgenic animals expressing NIF were made diabetic with streptozotocin and assessed for diabetes-induced retinal vascular abnormalities and leukocyte activation. To assess if the leukocyte blocking therapy compromised the immune system, animals were challenged with bacteria. Retinal superoxide production, leukostasis and leukocyte superoxide production were increased in wild type mice diabetic for 10 weeks, as was the ability of leukocytes isolated from diabetic animals to kill retinal endothelial cells in vitro. Retinal capillary degeneration was significantly increased in wild type mice diabetic 40 weeks. In contrast, mice expressing NIF did not develop any of these abnormalities, with the exception that non-diabetic and diabetic mice expressing NIF generated greater amounts of superoxide than did similar mice not expressing NIF. Importantly, NIF did not significantly impair the ability of mice to clear an opportunistic bacterial challenge, suggesting that NIF did not compromise immune surveillance. We conclude that antagonism of CD11b (integrin αmβ2 by NIF is sufficient to inhibit early stages of diabetic retinopathy, while not compromising the basic immune response.

  2. Antagonism of CD11b with neutrophil inhibitory factor (NIF) inhibits vascular lesions in diabetic retinopathy.

    Science.gov (United States)

    Veenstra, Alexander A; Tang, Jie; Kern, Timothy S

    2013-01-01

    Leukocytes and proteins that govern leukocyte adhesion to endothelial cells play a causal role in retinal abnormalities characteristic of the early stages of diabetic retinopathy, including diabetes-induced degeneration of retinal capillaries. Leukocyte integrin αmβ2 (CD11b/CD18, MAC1), a protein mediating adhesion, has been shown to mediate damage to endothelial cells by activated leukocytes in vitro. We hypothesized that Neutrophil Inhibitory Factor (NIF), a selective antagonist of integrin αmβ2, would inhibit the diabetes-induced degeneration of retinal capillaries by inhibiting the excessive interaction between leukocytes and retinal endothelial cells in diabetes. Wild type animals and transgenic animals expressing NIF were made diabetic with streptozotocin and assessed for diabetes-induced retinal vascular abnormalities and leukocyte activation. To assess if the leukocyte blocking therapy compromised the immune system, animals were challenged with bacteria. Retinal superoxide production, leukostasis and leukocyte superoxide production were increased in wild type mice diabetic for 10 weeks, as was the ability of leukocytes isolated from diabetic animals to kill retinal endothelial cells in vitro. Retinal capillary degeneration was significantly increased in wild type mice diabetic 40 weeks. In contrast, mice expressing NIF did not develop any of these abnormalities, with the exception that non-diabetic and diabetic mice expressing NIF generated greater amounts of superoxide than did similar mice not expressing NIF. Importantly, NIF did not significantly impair the ability of mice to clear an opportunistic bacterial challenge, suggesting that NIF did not compromise immune surveillance. We conclude that antagonism of CD11b (integrin αmβ2) by NIF is sufficient to inhibit early stages of diabetic retinopathy, while not compromising the basic immune response.

  3. Bilateral acute retinal necrosis after herpetic meningitis

    Directory of Open Access Journals (Sweden)

    Katsura T

    2012-04-01

    Full Text Available Keisho Hirota1,2, Masayuki Akimoto1,3, Toshiaki Katsura21Department of Ophthalmology, Kyoto Medical Center, National Hospital Organization, 2Internal Medicine, Kyoto Medical Center, 3Clinical Research Center, Kyoto Medical Center, Kyoto, JapanPurpose: The report of a case of bilateral acute retinal necrosis after herpetic meningitis.Case report: A 47-year-old man was admitted with the chief complaint of persistent high fever and transient loss of consciousness. Although his general condition improved after intravenous acyclovir administration, the patient presented with visual loss in both eyes 4 days after admission. Visual acuity in his right eye was 20/200 and his left eye had light perception alone. Both eyes showed panretinal arteritis diagnosed as acute retinal necrosis. Panretinal photocoagulation was performed for both eyes. Progression of retinal detachment was prevented in both eyes; however, visual acuity of the left eye was totally lost because of neovascular glaucoma. Visual acuity of the right eye recovered to 20/20.Conclusion: Although cases of bilateral acute retinal necrosis have been reported after herpetic encephalitis, this condition is rare after herpetic meningitis. Prophylactic acyclovir therapy and early panretinal photocoagulation may prevent retinal detachment and improve the prognosis. Neurologists and ophthalmologists should be aware that not only herpetic encephalitis but also herpetic meningitis can lead to acute retinal necrosis within a very short interval.Keywords: acute retinal necrosis, herpetic meningitis, herpes simplex, varicella zoster virus

  4. Genomic analysis of mouse retinal development.

    Directory of Open Access Journals (Sweden)

    Seth Blackshaw

    2004-09-01

    Full Text Available The vertebrate retina is comprised of seven major cell types that are generated in overlapping but well-defined intervals. To identify genes that might regulate retinal development, gene expression in the developing retina was profiled at multiple time points using serial analysis of gene expression (SAGE. The expression patterns of 1,051 genes that showed developmentally dynamic expression by SAGE were investigated using in situ hybridization. A molecular atlas of gene expression in the developing and mature retina was thereby constructed, along with a taxonomic classification of developmental gene expression patterns. Genes were identified that label both temporal and spatial subsets of mitotic progenitor cells. For each developing and mature major retinal cell type, genes selectively expressed in that cell type were identified. The gene expression profiles of retinal Müller glia and mitotic progenitor cells were found to be highly similar, suggesting that Müller glia might serve to produce multiple retinal cell types under the right conditions. In addition, multiple transcripts that were evolutionarily conserved that did not appear to encode open reading frames of more than 100 amino acids in length ("noncoding RNAs" were found to be dynamically and specifically expressed in developing and mature retinal cell types. Finally, many photoreceptor-enriched genes that mapped to chromosomal intervals containing retinal disease genes were identified. These data serve as a starting point for functional investigations of the roles of these genes in retinal development and physiology.

  5. Protective effects of human iPS-derived retinal pigment epithelium cell transplantation in the retinal dystrophic rat.

    Directory of Open Access Journals (Sweden)

    Amanda-Jayne Carr

    Full Text Available Transformation of somatic cells with a set of embryonic transcription factors produces cells with the pluripotent properties of embryonic stem cells (ESCs. These induced pluripotent stem (iPS cells have the potential to differentiate into any cell type, making them a potential source from which to produce cells as a therapeutic platform for the treatment of a wide range of diseases. In many forms of human retinal disease, including age-related macular degeneration (AMD, the underlying pathogenesis resides within the support cells of the retina, the retinal pigment epithelium (RPE. As a monolayer of cells critical to photoreceptor function and survival, the RPE is an ideally accessible target for cellular therapy. Here we report the differentiation of human iPS cells into RPE. We found that differentiated iPS-RPE cells were morphologically similar to, and expressed numerous markers of developing and mature RPE cells. iPS-RPE are capable of phagocytosing photoreceptor material, in vitro and in vivo following transplantation into the Royal College of Surgeons (RCS dystrophic rat. Our results demonstrate that iPS cells can be differentiated into functional iPS-RPE and that transplantation of these cells can facilitate the short-term maintenance of photoreceptors through phagocytosis of photoreceptor outer segments. Long-term visual function is maintained in this model of retinal disease even though the xenografted cells are eventually lost, suggesting a secondary protective host cellular response. These findings have identified an alternative source of replacement tissue for use in human retinal cellular therapies, and provide a new in vitro cellular model system in which to study RPE diseases affecting human patients.

  6. Automatic diagnosis of retinal diseases from color retinal images

    CERN Document Server

    Jayanthi, D; SwarnaParvathi, S

    2010-01-01

    Teleophthalmology holds a great potential to improve the quality, access, and affordability in health care. For patients, it can reduce the need for travel and provide the access to a superspecialist. Ophthalmology lends itself easily to telemedicine as it is a largely image based diagnosis. The main goal of the proposed system is to diagnose the type of disease in the retina and to automatically detect and segment retinal diseases without human supervision or interaction. The proposed system will diagnose the disease present in the retina using a neural network based classifier.The extent of the disease spread in the retina can be identified by extracting the textural features of the retina. This system will diagnose the following type of diseases: Diabetic Retinopathy and Drusen.

  7. Improvement in retinal venous oxygen saturation after panretinal photocoagulation is predictive of progression of proliferative diabetic retinopathy

    DEFF Research Database (Denmark)

    Torp, Thomas Lee; Kawasaki, Ryo; Wong, Tien Yin

    We performed a prospective, interventional clinical study on patients with proliferative diabetic retinopathy (PDR) in order to investigate changes in retinal oximetry before and three months after panretinal photocoagulation (PRP) and to correlate this to PDR-activity. Thirty-nine eyes from 34 p...... PRP was independently associated with PDR-activity. This might reflect absence in reduction in vascular endothelial growth factor (VEGF) and could be a potential non-invasive marker of disease activity....

  8. Regulation Effect of Vascular Endothelial Growth Factor on Human Fetal Choroid Vascularization

    Institute of Scientific and Technical Information of China (English)

    JinsongZhao; YiWang; 等

    2002-01-01

    Purpose:To investigate the spatial and temporal regulation effect of vascular endothelial growth factor(VEGF) on human fetal choroids vascularization.Methods:The eyeballs of 54 human fetuses from the 9th week to the 40th week due to accidental abortion were studied by immunohistochemically stainin for the expression of VEGF and proliferation cell nuclear antigen (PCNA).Results: (1)The distribution of VEGF expression in the retinal pigment epithelium (RPE) decreased with the incrase of age,the peak of which was between the 9th and 14th week.(2)PCNA immunoreactivity was localized within choriocapillaris endothelium .The expression level decreased alone with fetus age.In this period the choriocapillaris endothelium kept proliferation,differentiation,canalization and remodeled to form the choroids vessels(3)Statistically significant correlations were shown between the expression of VEGF in the PRE and that of PCNA in choriocapillaris endothelium(r=0.933,P<0.01).Couclusin:VEGF expression in PRE was positively involved in modulating human fetal choroids vascularization .Eye Science 2000;16:11-14.

  9. Regulation Effect of Vascular Endothelial Growth Factor on Human Fetal Choroid Vascularization

    Institute of Scientific and Technical Information of China (English)

    Jinsong Zhao; Yue Song; Yi Wang; Xiaoguang Zhang

    2000-01-01

    Purpose: To investigate the spatial and temporal regulation effect of vascular endothelial growth factor(VEGF) on human fetal choroid vascularization. Methods: The eyeballs of 54 human fetuses from the 9th week to the 40th week due to accidental abortion were studied by immunohistochemically staining for the expression of VEGF and proliferation cell nuclear antigen (PCNA). Results: (1) The distribution of VEGF expression in the retinal pigment epithelium (RPE) decreased with the increase of age, the peak of which was between the 9th and 14th week. (2) PCNA immunoreactivity was localized within choriocapillaris endothelium. The expression level decreased alone with fetus age. In this period the choriocapillaris endothelium kept proliferation, differentiation, canalization and remodelled to form the choroid vessels. (3)Statistically significant correlations were shown between the expression of VEGF in the PRE and that of PCNA in choriocapillaris endothelium(r =0. 933, P < 0. 01). Conclusion: VEGF expression in RPE was positively involved in modulating human fetal choroid vascularization. Eye Science 2000; 16:11 ~ 14.

  10. [New drug therapy for retinal degeneration].

    Science.gov (United States)

    Ohguro, Hiroshi

    2008-01-01

    Retinitis pigmentosa (RP) is an inherited retinal degeneration characterized by nyctalopia, ring scotoma, and bone-spicule pigmentation of the retina. So far, no effective therapy has been found for RP. As a possible molecular etiology of RP, retina-specific gene deficits are most likely involved, but little has been identified in terms of intracellular mechanisms leading to retinal photoreceptor cell death at post-translational levels. In order to find an effective therapy for RP, we must look for underlying common mechanisms that are responsible for the development of RP, instead of designing a specific therapy for each of the RP types with different causes. Therefore, in the present study, several animal models with different causes of RP were studied, including (1)Royal College of Surgeons (RCS) rats with a deficit of retinal pigment epithelium (RPE) function caused by rhodopsin mutation; (2) P23H rats, (3) S334ter rats, (4) photo stress rats, (5) retinal degeneration (rd) mice with a deficit of phosphodiesterase(PDE) function; and (6) cancer-associated retinopathy (CAR) model rats with a deficit of recoverin-dependent photoreceptor adaptation function. In each of these models, the following assessments were made in order to elucidate common pathological mechanisms among the models: (1) retinal function assessed by electroretinogram (ERG), (2) retinal morphology, (3) retinoid analysis, (4) rhodopsin regeneration, (5) rhodopsin phosphorylation and dephosphorylation, and (6) cytosolic cGMP levels. We found that unregulated photoreceptor adaptation processes caused by an imbalance of rhodopsin phosphorylation and dephosphorylation caused retinal dysfunction leading to photoreceptor cell death. As possible candidate drugs for normalizing these retinal dysfunctions and stopping further retinal degeneration, nilvadipine, a Ca channel blocker, retinoid derivatives, and anthocyanine were chosen and tested to determine their effect on the above animal models with

  11. Fluid vitreous substitutes in vitreo retinal surgery.

    Science.gov (United States)

    Saxena, S; Gopal, L

    1996-12-01

    Advances in the surgical instrumentation and vitreoretinal techniques have allowed intraoperative reapproximation of retina to a more normal position. The use of intravitreally injected liquid materials (viscoelastic liquids, liquid perfluorocarbons and silicone oil), as adjunctive agents to vitreo-retinal surgery play an important role in facilitating retinal reattachment. These materials are used as intraoperative instruments to re-establish intraocular volume, assist in separating membranes adherent to the retina, manipulate retinal detachments and mechanically flatten detached retina. Over the longer term, silicone oil maintains intraocular tamponade. One should be cognizant of the potential uses, benefits and risks of each of these vitreous substitutes.

  12. Fluid vitreous substitutes in vitreo retinal surgery

    Directory of Open Access Journals (Sweden)

    Saxena Sandeep

    1996-01-01

    Full Text Available Advances in the surgical instrumentation and vitreoretinal techniques have allowed intraoperative reapproximation of retina to a more normal position. The use of intravitreally injected liquid materials (viscoelastic liquids, liquid perfluorocarbons and silicone oil, as adjunctive agents to vitreo-retinal surgery play an important role in facilitating retinal reattachment. These materials are used as intraoperative instruments to re-establish intraocular volume, assist in separating membranes adherent to the retina, manipulate retinal detachments and mechanically flatten detached retina. Over the longer term, silicone oil maintains intraocular tamponade. One should be cognizant of the potential uses, benefits and risks of each of these vitreous substitutes.

  13. Unilateral central retinal artery occlusion as the sole presenting sign of Susac syndrome in a young man: case report

    Directory of Open Access Journals (Sweden)

    Samira Luiza dos Apóstolos-Pereira

    2013-06-01

    Full Text Available We report the case of a 24-year-old man presenting with sudden visual loss in the left eye from a central retinal artery occlusion. An extensive clinical investigation revealed no etiology. Three weeks later, however, the patient developed hearing loss followed by encephalopathy and multiple branch retinal artery occlusions in the right eye. Fluorescein angiography confirmed retinal vascular occlusions with no sign of vasculitis. The neurological examination revealed a diffuse encephalopathy while the MRI scan disclosed several small areas of infarcts in the brain. Bilateral sensorineural hearing loss was confirmed on audiometry. The patient was diagnosed with Susac syndrome and treated with methylprednisolone and cyclophosphamide, resulting in slight improvement and stabilization. This case shows that Susac syndrome may be diagnosed late due to the absence at onset of one or more of the symptoms of the classic triad (encephalopathy, multiple branch retinal artery occlusions and hearing loss. This case also serves to emphasize that Susac syndrome should be considered in the differential diagnosis of central retinal artery occlusion, even in apparently healthy young men.

  14. Effect of adenovirus-mediated slit2 shRNA on hypoxia-induced expression of vascular endothelial growth factor in human retinal pigment epithelial cells%腺病毒介导的slit2 shRNA对缺氧诱导的人视网膜色素上皮细胞中血管内皮生长因子表达的影响

    Institute of Scientific and Technical Information of China (English)

    黄莉芸; 周希瑗

    2014-01-01

    目的 观察腺病毒介导的slit2 shRNA对缺氧诱导的人视网膜色素上皮细胞(retinal pigment epithelial cells,RPE)中血管内皮生长因子(vascular endothelial growth factor,VEGF)表达的影响,探讨slit2在脉络膜新生血管(chorodal neovascularation,CNV)中的可能作用,为CNV的治疗提供新的思路.方法 分别采用RT-PCR和免疫组化法检测人视网膜色素上皮-19(ARPE-19)细胞中slit2及受体Robo1基因mRNA的转录和蛋白的表达;用200 μmol/L氯化钴处理人ARPE-19细胞,建立化学缺氧模型,以未缺氧组作为对照,采用Real-time PCR和Western blot法检测在缺氧状态下细胞中slit2、Robo1、VEGF基因mRNA及蛋白水平表达的变化;将缺氧的人ARPE-19细胞随机分为shRNA处理组(加入Ad-slit2-shRNA)、空腺病毒组(加入空腺病毒)和缺氧组,24 h后收集各组细胞,Real-time PCR和Western blot法检测slit2 shRNA干扰后细胞中slit2、Robo1、VEGF基因mRNA和蛋白水平表达的变化,ELISA法检测细胞培养上清中VEGF蛋白水平的变化.结果 在正常人ARPE-19细胞中有slit2和Robo1基因mRNA的转录及蛋白的表达;缺氧组人ARPE-19细胞中slit2、Robo1、VEGF基因mRNA和蛋白的表达水平均较未缺氧组明显升高(P<0.05);与缺氧组相比,slit2-shRNA处理组人ARPE-19细胞中slit2、Robo1、VEGF基因mRNA和蛋白的表达水平均明显降低(P<0.05),缺氧组与空腺病毒组slit2、Robo1、VEGF的变化差异无统计学意义(P>0.05).结论 slit2 shRNA沉默RPE细胞中的slit2后,可明显抑制缺氧诱导的RPE细胞中VEGF的表达,为临床CNV的治疗提供了新的思路.

  15. Modulation of Vascular Cell Function by Bim Expression

    Directory of Open Access Journals (Sweden)

    Margaret E. Morrison

    2013-01-01

    Full Text Available Apoptosis of vascular cells, including pericytes and endothelial cells, contributes to disease pathogenesis in which vascular rarefaction plays a central role. Bim is a proapoptotic protein that modulates not only apoptosis but also cellular functions such as migration and extracellular matrix (ECM protein expression. Endothelial cells and pericytes each make a unique contribution to vascular formation and function although the details require further delineation. Here we set out to determine the cell autonomous impact of Bim expression on retinal endothelial cell and pericyte function using cells prepared from Bim deficient (Bim−/− mice. Bim−/− endothelial cells displayed an increased production of ECM proteins, proliferation, migration, adhesion, and VEGF expression but, a decreased eNOS expression and nitric oxide production. In contrast, pericyte proliferation decreased in the absence of Bim while migration, adhesion, and VEGF expression were increased. In addition, we demonstrated that the coculturing of either wild-type or Bim−/− endothelial cells with Bim−/− pericytes diminished their capillary morphogenesis. Thus, our data further emphasizes the importance of vascular cell autonomous regulatory mechanisms in modulation of vascular function.

  16. Modulation of vascular cell function by bim expression.

    Science.gov (United States)

    Morrison, Margaret E; Palenski, Tammy L; Jamali, Nasim; Sheibani, Nader; Sorenson, Christine M

    2013-01-01

    Apoptosis of vascular cells, including pericytes and endothelial cells, contributes to disease pathogenesis in which vascular rarefaction plays a central role. Bim is a proapoptotic protein that modulates not only apoptosis but also cellular functions such as migration and extracellular matrix (ECM) protein expression. Endothelial cells and pericytes each make a unique contribution to vascular formation and function although the details require further delineation. Here we set out to determine the cell autonomous impact of Bim expression on retinal endothelial cell and pericyte function using cells prepared from Bim deficient (Bim(-/-)) mice. Bim(-/-) endothelial cells displayed an increased production of ECM proteins, proliferation, migration, adhesion, and VEGF expression but, a decreased eNOS expression and nitric oxide production. In contrast, pericyte proliferation decreased in the absence of Bim while migration, adhesion, and VEGF expression were increased. In addition, we demonstrated that the coculturing of either wild-type or Bim(-/-) endothelial cells with Bim(-/-) pericytes diminished their capillary morphogenesis. Thus, our data further emphasizes the importance of vascular cell autonomous regulatory mechanisms in modulation of vascular function.

  17. Long-term outcomes in patients undergoing vitrectomy for retinal detachment due to viral retinitis

    Directory of Open Access Journals (Sweden)

    Almeida DRP

    2015-07-01

    Full Text Available David RP Almeida,1 Eric K Chin,1 Ryan M Tarantola,1 Elizabeth O Tegins,1 Christopher A Lopez,1 Herbert Culver Boldt,1 Karen M Gehrs,1 Elliott H Sohn,1 Stephen R Russell,1 James C Folk,1 Vinit B Mahajan1,2 1Department of Ophthalmology and Visual Sciences, 2Omics Laboratory, University of Iowa Hospitals and Clinics, Iowa City, IA, USA Purpose: To determine the outcomes in patients with rhegmatogenous retinal detachment (RRD secondary to viral retinitis. Patients and methods: This was a retrospective, consecutive, noncomparative, interventional case series of 12 eyes in ten patients with RRD secondary to viral retinitis. Results of vitreous or aqueous biopsy, effect of antiviral therapeutics, time to retinal detachment, course of visual acuity, and anatomic and surgical outcomes were investigated. Results: There were 1,259 cases of RRD during the study period, with 12 cases of RRD secondary to viral retinitis (prevalence of 0.95%. Follow-up was available for a mean period of 4.4 years. Varicella zoster virus was detected in six eyes, herpes simplex virus in two eyes, and cytomegalovirus in two eyes. Eight patients were treated with oral valacyclovir and two patients with intravenous acyclovir. Lack of optic nerve involvement correlated with improved final visual acuity of 20/100 or greater. Pars plana vitrectomy (n=12, silicone-oil tamponade (n=11, and scleral buckling (n=10 provided successful anatomic retinal reattachment in all cases, with no recurrent retinal detachment and no cases of hypotony during the follow-up period. Conclusion: Varicella zoster virus was the most frequent cause of viral retinitis, and lack of optic nerve involvement was predictive of a favorable visual acuity prognosis. Vitrectomy with silicone-oil tamponade and scleral buckle placement provided stable anatomical outcomes. Keywords: viral retinitis, acute retinal necrosis, herpetic retinitis, vitrectomy, retinal detachment 

  18. The cost-effectiveness of the Argus II retinal prosthesis in Retinitis Pigmentosa patients

    OpenAIRE

    2014-01-01

    Background Retinitis Pigmentosa (RP) is a hereditary genetic disease causing bilateral retinal degeneration. RP is a leading cause of blindness resulting in incurable visual impairment and drastic reduction in the Quality of life of the patients. Second Sight Medical Products Inc. developed Argus II, a retinal prosthesis system for treating RP. Argus II is the world’s first ever-commercial implant intended to restore some vision in the blind patients. The objective of this study was to assess...

  19. HIF-1alpha and HIF-2alpha are differentially activated in distinct cell populations in retinal ischaemia.

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    Freya M Mowat

    Full Text Available BACKGROUND: Hypoxia plays a key role in ischaemic and neovascular disorders of the retina. Cellular responses to oxygen are mediated by hypoxia-inducible transcription factors (HIFs that are stabilised in hypoxia and induce the expression of a diverse range of genes. The purpose of this study was to define the cellular specificities of HIF-1alpha and HIF-2alpha in retinal ischaemia, and to determine their correlation with the pattern of retinal hypoxia and the expression profiles of induced molecular mediators. METHODOLOGY/PRINCIPAL FINDINGS: We investigated the tissue distribution of retinal hypoxia during oxygen-induced retinopathy (OIR in mice using the bio-reductive drug pimonidazole. We measured the levels of HIF-1alpha and HIF-2alpha proteins by Western blotting and determined their cellular distribution by immunohistochemistry during the development of OIR. We measured the temporal expression profiles of two downstream mediators, vascular endothelial growth factor (VEGF and erythropoietin (Epo by ELISA. Pimonidazole labelling was evident specifically in the inner retina. Labelling peaked at 2 hours after the onset of hypoxia and gradually declined thereafter. Marked binding to Müller glia was evident during the early hypoxic stages of OIR. Both HIF-1alpha and HIF-2alpha protein levels were significantly increased during retinal hypoxia but were evident in distinct cellular distributions; HIF-1alpha stabilisation was evident in neuronal cells throughout the inner retinal layers whereas HIF-2alpha was restricted to Müller glia and astrocytes. Hypoxia and HIF-alpha stabilisation in the retina were closely followed by upregulated expression of the downstream mediators VEGF and EPO. CONCLUSIONS/SIGNIFICANCE: Both HIF-1alpha and HIF-2alpha are activated in close correlation with retinal hypoxia but have contrasting cell specificities, consistent with differential roles in retinal ischaemia. Our findings suggest that HIF-2alpha activation

  20. microRNA-218 Inhibits Oxygen-induced Retinal Neovascularization via Reducing the Expression of Roundabout 1

    Institute of Scientific and Technical Information of China (English)

    Shuang Han; Yi-Chun Kong; Bei Sun; Quan-Hong Han; Ying Chen; Yu-Chuan Wang

    2016-01-01

    Background:The mechanisms of pathological retinal neovascularization (RNV) remain unknown.Several microRNAs were reported to be involved in the process of RNV.Oxygen-induced retinopathy (OIR) is a useful model to investigate RNV.Our present work explored the expression and the role of microRNA-128 (miR-218) in oxygen-induced RNV.Methods:OIR was used to establish RNV model.The expression level ofmiR-218 in the retina from OIR mice was assessed by quantitative real-time reverse transcfiptase polymerase chain reaction.Fluorescein angiography was performed in retinae of OIR mice,and RNV was quantified by hematoxylin and eosin staining to evaluate the effect of pCDH-CMV-miR-218 intravitreal injection on RNV in OIR mice.Roundabout 1 (Robo 1) expression was detected by Western blotting in mouse retinal vascular endothelial cells expressing a high or low level ofmiR-218 and retinal tissues from OIR mice.Cell migration was evaluated by scratch wound assay.Results:In OIR mice,the expression level of miR-218 was significantly down-regulated (P =0.006).Retinal Robo1 expression was significantly increased at both mRNA and protein levels (P =0.001,0.008;respectively),miR-218 intravitreal injection inhibited retinal angiogenesis in OIR mice,and the restoration of miR-218 in retina led to down-regulation of Robo 1.Conclusions:Our experiments showed that restoration of miR-218 inhibited retinal angiogenesis via targeting Robo 1.MiR-218 contributed to the inhibition of retinal angiogenesis and miR-218 might be a new therapeutic target for preventing RNV.

  1. A CNGB1 frameshift mutation in Papillon and Phalene dogs with progressive retinal atrophy.

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    Saija J Ahonen

    Full Text Available Progressive retinal degenerations are the most common causes of complete blindness both in human and in dogs. Canine progressive retinal atrophy (PRA or degeneration resembles human retinitis pigmentosa (RP and is characterized by a progressive loss of rod photoreceptor cells followed by a loss of cone function. The primary clinical signs are detected as vision impairment in a dim light. Although several genes have been associated with PRAs, there are still PRAs of unknown genetic cause in many breeds, including Papillons and Phalènes. We have performed a genome wide association and linkage studies in cohort of 6 affected Papillons and Phalènes and 14 healthy control dogs to map a novel PRA locus on canine chromosome 2, with a 1.9 Mb shared homozygous region in the affected dogs. Parallel exome sequencing of a trio identified an indel mutation, including a 1-bp deletion, followed by a 6-bp insertion in the CNGB1 gene. This mutation causes a frameshift and premature stop codon leading to probable nonsense mediated decay (NMD of the CNGB1 mRNA. The mutation segregated with the disease and was confirmed in a larger cohort of 145 Papillons and Phalènes (PFisher = 1.4×10(-8 with a carrier frequency of 17.2 %. This breed specific mutation was not present in 334 healthy dogs from 10 other breeds or 121 PRA affected dogs from 44 other breeds. CNGB1 is important for the photoreceptor cell function its defects have been previously associated with retinal degeneration in both human and mouse. Our study indicates that a frameshift mutation in CNGB1 is a cause of PRA in Papillons and Phalènes and establishes the breed as a large functional animal model for further characterization of retinal CNGB1 biology and possible retinal gene therapy trials. This study enables also the development of a genetic test for breeding purposes.

  2. Retinal photodamage by endogenous and xenobiotic agents.

    Science.gov (United States)

    Wielgus, Albert R; Roberts, Joan E

    2012-01-01

    The human eye is constantly exposed to sunlight and artificial lighting. Light transmission through the eye is fundamental to its unique biological functions of directing vision and circadian rhythm and therefore light absorbed by the eye must be benign. However, exposure to the very intense ambient radiation can pose a hazard particularly if the recipient is over 40 years of age. There are age-related changes in the endogenous (natural) chromophores (lipofuscin, A2E and all-trans-retinal derivatives) in the human retina that makes it more susceptible to visible light damage. Intense visible light sources that do not filter short blue visible light (400-440 nm) used for phototherapy of circadian imbalance (i.e. seasonal affective disorder) increase the risk for age-related light damage to the retina. Moreover, many drugs, dietary supplements, nanoparticles and diagnostic dyes (xenobiotics) absorb ocular light and have the potential to induce photodamage to the retina, leading to transient or permanent blinding disorders. This article will review the underlying reasons why visible light in general and short blue visible light in particular dramatically raises the risk of photodamage to the human retina.

  3. Electrophysiological abnormalities associated with extensive myelinated retinal nerve fibers

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    Su Ann Tay

    2012-01-01

    Full Text Available An observational case report of electrophysiological abnormalities in a patient with anisomyopic amblyopia as a result of unilateral extensive myelinated retinal nerve fibers (MNFs is illustrated. The electrophysiological readings revealed an abnormal pattern electroretinogram (PERG but normal full-field electroretinogram readings in the affected eye. The visual-evoked potential was also undetectable in that eye. Our findings suggest that extensive MNFs can be associated with electrophysiological abnormalities, in particular the PERG, which can aid in diagnosing the cause of impaired vision when associated with amblyopia.

  4. The burden and spectrum of vitreo-retinal diseases among ophthalmic outpatients in a resource-deficient tertiary eye care setting in South-Eastern Nigeria

    Directory of Open Access Journals (Sweden)

    Eze Boniface

    2010-01-01

    Full Text Available Purpose: This study was designed to determine the rate and pattern of vitreo-retinal diseases at a tertiary eye care center in South-eastern Nigeria. Materials and Methods: The outpatient register at the Eye Clinic of the University of Nigeria Teaching Hospital, Enugu, was retrospectively examined to identify all new patients registered between January 2004 and December 2008. A chart review of subjects with vitreo-retinal disease was conducted to record relevant demographic and clinical data including the needs for vitreo-retinal care. Descriptive and analytical statistics were performed. A P-value < 0.001 (one degree of freedom was considered statistically significant. Results: Of the 8,239 new patients reported during the period, 326 subjects (males- 59.3%; females- 40.7%; sex ratio = 1.1:1 aged 49.3 ± 16.8 years (range 3-82 years had vitreo-retinal disease. The rate of vitreo-retinal disease was 3.9%. The rate was higher in subjects above 40 years old (P < 0.001, but did not differ between sexes (P = 0.469. Diabetic retinopathy (24.9%, hypertensive retinopathy (13.3%, and age-related macular degeneration (10.7% were the leading vitreo-retinal diseases. Blindness from vitreo-retinal disease was bilateral in 6.1% of subjects and unilateral in 17.5% of subjects. The common co-morbidities were ocular conditions such as refractive error (19.8%, cataract (14.2%, and glaucoma (10.4%; and systemic conditions such as diabetes mellitus (14.6% and hypertension (13.2%. Conclusions: The rate of vitreo-retinal diseases among new ophthalmic outpatients at UNTH, Enugu, is 3.9%. Retinal vascular disorders and age-related maculopathy are the leading retinal diseases. At UNTH, resource needs for vitreo-retinal care are urgent including retinal photography/angiography, laser photocoagulation, intra-vitreal pharmacotherapy, and vitreo-retinal surgery.

  5. Comparative proteomic analysis of histone post-translational modifications upon ischemia/reperfusion-induced retinal injury

    DEFF Research Database (Denmark)

    Zhao, Xiaolu; Sidoli, Simone; Wang, Leilei;

    2014-01-01

    We present a detailed quantitative map of single and coexisting histone post-translational modifications (PTMs) in rat retinas affected by ischemia and reperfusion (I/R) injury. Retinal I/R injury contributes to serious ocular diseases, which can lead to vision loss and blindness. We applied linear...

  6. Retinal vessel caliber, choroidal thickness and ocular pulse amplitude measurements in essential thrombocythemia

    Directory of Open Access Journals (Sweden)

    Gökhan Pekel

    2016-01-01

    Conclusions: Our results indicate that choroidal thickness and pulsatile blood flow are not significantly affected in ET and under high blood platelet counts. Retinal arteriolar and venular calibers are thinner in ET when compared to age.sex matched healthy controls.

  7. Profile and Determinants of Retinal Optical Intensity in Normal Eyes with Spectral Domain Optical Coherence Tomography.

    Directory of Open Access Journals (Sweden)

    Binyao Chen

    Full Text Available To investigate the profile and determinants of retinal optical intensity in normal subjects using 3D spectral domain optical coherence tomography (SD OCT.A total of 231 eyes from 231 healthy subjects ranging in age from 18 to 80 years were included and underwent a 3D OCT scan. Forty-four eyes were randomly chosen to be scanned by two operators for reproducibility analysis. Distribution of optical intensity of each layer and regions specified by the Early Treatment of Diabetic Retinopathy Study (ETDRS were investigated by analyzing the OCT raw data with our automatic graph-based algorithm. Univariate and multivariate analyses were performed between retinal optical intensity and sex, age, height, weight, spherical equivalent (SE, axial length, image quality, disc area and rim/disc area ratio (R/D area ratio.For optical intensity measurements, the intraclass correlation coefficient of each layer ranged from 0.815 to 0.941, indicating good reproducibility. Optical intensity was lowest in the central area of retinal nerve fiber layer, ganglion cell layer, inner plexiform layer, inner nuclear layer, outer plexiform layer and photoreceptor layer, except for the retinal pigment epithelium (RPE. Optical intensity was positively correlated with image quality in all retinal layers (0.5530.05. There was no relationship between retinal optical intensity and sex, height, weight, SE, axial length, disc area and R/D area ratio.There was a specific pattern of distribution of retinal optical intensity in different regions. The optical intensity was affected by image quality and age. Image quality can be used as a reference for normalization. The effect of age needs to be taken into consideration when using OCT for diagnosis.

  8. Post-fever retinitis: a single center experience from south India.

    Science.gov (United States)

    Vishwanath, Srilatha; Badami, Kalpana; Sriprakash, K S; Sujatha, B L; Shashidhar, S D; Shilpa, Y D

    2014-08-01

    Various retinal manifestations can occur following a febrile illness due to viral, bacterial or protozoal etiology. As there are limited data in the literature, we undertook this study to analyse the clinical presentation of post-fever retinitis due to various etiologies, as well as its course and management. This was a retrospective study of 14 consecutive cases who presented to the Vitreo Retina Department of our hospital over a 1-year period between January 2010 and December 2010. All patients underwent detailed ophthalmic examination and relevant investigations including fundus fluorescein angiography and optical coherence tomography (OCT). Basic and specific investigations were performed as necessary. All patients were given systemic steroids which were tapered based on clinical response. Twenty-one eyes of 14 patients (7 bilateral, 7 unilateral) were studied. Onset of ocular symptoms was approximately 3 weeks after fever. Four patients had specific etiology-one each of chikungunya, enteric fever, malaria and abdominal abscess with pneumococcal pneumonia. The presenting visual acuity of the affected eyes averaged 2/60. Six eyes had relative afferent pupillary defect. All patients had solitary or multiple patches of retinitis at the posterior pole and exudation at the macula. OCT through the lesions revealed inner retinal hyperreflectivity and thickening with after-shadowing. All patients showed improvement in vision with unilateral cases improving to an average of 6/12 and bilateral cases improving to an average of 6/24. Patients also showed resolution of retinitis, macular edema and serous detachment. Post-fever retinitis as a condition manifested approximately 3 weeks after onset of fever. Irrespective of the cause of the fever, clinical presentation of cases was similar with inner retinitis at the posterior pole and a favourable response to steroids, suggesting a possible immunological basis for this condition.

  9. Idiopathic pediatric retinal artery occlusion

    Directory of Open Access Journals (Sweden)

    Manayath George

    2010-01-01

    Full Text Available We report a case of branch retinal artery occlusion (BRAO in a healthy young girl. An eight-year-old girl presented with sudden loss of vision in her left eye. She had a pale retina with macular edema consistent with extensive BRAO. A thorough workup was performed to determine any etiologic factor. All test results were within normal limits. Her visual acuity improved from finger counting to 20/40 over two weeks, on immediate treatment with intravenous steroids (methyl prednisolone. This case suggests that BRAO can occur in healthy children without any detectable systemic or ocular disorders and a dramatic improvement may be achieved with prompt treatment with intravenous steroids.

  10. Integration of retinal image sequences

    Science.gov (United States)

    Ballerini, Lucia

    1998-10-01

    In this paper a method for noise reduction in ocular fundus image sequences is described. The eye is the only part of the human body where the capillary network can be observed along with the arterial and venous circulation using a non invasive technique. The study of the retinal vessels is very important both for the study of the local pathology (retinal disease) and for the large amount of information it offers on systematic haemodynamics, such as hypertension, arteriosclerosis, and diabetes. In this paper a method for image integration of ocular fundus image sequences is described. The procedure can be divided in two step: registration and fusion. First we describe an automatic alignment algorithm for registration of ocular fundus images. In order to enhance vessel structures, we used a spatially oriented bank of filters designed to match the properties of the objects of interest. To evaluate interframe misalignment we adopted a fast cross-correlation algorithm. The performances of the alignment method have been estimated by simulating shifts between image pairs and by using a cross-validation approach. Then we propose a temporal integration technique of image sequences so as to compute enhanced pictures of the overall capillary network. Image registration is combined with image enhancement by fusing subsequent frames of a same region. To evaluate the attainable results, the signal-to-noise ratio was estimated before and after integration. Experimental results on synthetic images of vessel-like structures with different kind of Gaussian additive noise as well as on real fundus images are reported.

  11. Photodiode circuits for retinal prostheses.

    Science.gov (United States)

    Loudin, J D; Cogan, S F; Mathieson, K; Sher, A; Palanker, D V

    2011-10-01

    Photodiode circuits show promise for the development of high-resolution retinal prostheses. While several of these systems have been constructed and some even implanted in humans, existing descriptions of the complex optoelectronic interaction between light, photodiode, and the electrode/electrolyte load are limited. This study examines this interaction in depth with theoretical calculations and experimental measurements. Actively biased photoconductive and passive photovoltaic circuits are investigated, with the photovoltaic circuits consisting of one or more diodes connected in series, and the photoconductive circuits consisting of a single diode in series with a pulsed bias voltage. Circuit behavior and charge injection levels were markedly different for platinum and sputtered iridium-oxide film (SIROF) electrodes. Photovoltaic circuits were able to deliver 0.038 mC/cm(2) (0.75 nC/phase) per photodiode with 50- μm platinum electrodes, and 0.54-mC/cm(2) (11 nC/phase) per photodiode with 50-μ m SIROF electrodes driven with 0.5-ms pulses of light at 25 Hz. The same pulses applied to photoconductive circuits with the same electrodes were able to deliver charge injections as high as 0.38 and 7.6 mC/cm(2) (7.5 and 150 nC/phase), respectively. We demonstrate photovoltaic stimulation of rabbit retina in-vitro, with 0.5-ms pulses of 905-nm light using peak irradiance of 1 mW/mm(2). Based on the experimental data, we derive electrochemical and optical safety limits for pixel density and charge injection in various circuits. While photoconductive circuits offer smaller pixels, photovoltaic systems do not require an external bias voltage. Both classes of circuits show promise for the development of high-resolution optoelectronic retinal prostheses.

  12. Profile of retinal vasculitis in a tertiary eye care center in Eastern India

    Directory of Open Access Journals (Sweden)

    Kumar Saurabh

    2011-01-01

    Full Text Available Aims: To provide a fact file on the etiology, clinical presentations and management of retinal vasculitis in Eastern India. Materials and Methods: Retrospective, record based analysis of retinal vasculitis cases in a tertiary care center in Eastern India from January 2007 to December 2009 . Results: One hundred and thirteen eyes of 70 patients of retinal vasculitis were included in this study. Sixty (85.7% patients were male (mean age 33± 11.1 years and 10 (14.3% were female (mean age 32.4 ± 13.6 years. Vasculitis was bilateral in 43 (61.4% and unilateral in 27 (38.6% patients. Commonest symptoms were dimness of vision (73; 64.6% and floaters (36; 31.9%. Vascular sheathing (82; 72.6% and vitritis (51; 45.1% were commonest signs. Mantoux test was positive in 21 (30% patients but tuberculosis was confirmed in only four (5.71% patients. Raised serum angiotensin-converting enzyme level and positive antinuclear antibody level were reported in four (5.71% patients each. Human leukocyte antigen B5 (HLA B5 marker was present in one (1.4% patient. However, none of the total 70 patients were found to have a conclusively proven systemic disease attributable as the cause of retinal vasculitis. Oral corticosteroid (60; 85.7% was the mainstay of treatment. Forty-eight (42.5% eyes maintained their initial visual acuity and 43 (38% gained one or more line at mean follow-up of 16.6± 6.3 months. Conclusion: Retinal vasculitis cases had similar clinical presentations and common treatment plan. There was no systemic disease association with vasculitis warranting a careful approach in prescribing investigations.

  13. Imaging retinal mosaics in the living eye.

    Science.gov (United States)

    Rossi, E A; Chung, M; Dubra, A; Hunter, J J; Merigan, W H; Williams, D R

    2011-03-01

    Adaptive optics imaging of cone photoreceptors has provided unique insight into the structure and function of the human visual system and has become an important tool for both basic scientists and clinicians. Recent advances in adaptive optics retinal imaging instrumentation and methodology have allowed us to expand beyond cone imaging. Multi-wavelength and fluorescence imaging methods with adaptive optics have allowed multiple retinal cell types to be imaged simultaneously. These new methods have recently revealed rod photoreceptors, retinal pigment epithelium (RPE) cells, and the smallest retinal blood vessels. Fluorescence imaging coupled with adaptive optics has been used to examine ganglion cells in living primates. Two-photon imaging combined with adaptive optics can evaluate photoreceptor function non-invasively in the living primate retina.

  14. Regulatory and Economic Considerations of Retinal Drugs.

    Science.gov (United States)

    Shah, Ankoor R; Williams, George A

    2016-01-01

    The advent of anti-VEGF therapy for neovascular age-related macular degeneration and macular edema secondary to retinal vein occlusion and diabetes mellitus has prevented blindness in tens of thousands of people. However, the costs of these drugs are without precedent in ophthalmic drug therapeutics. An analysis of the financial implications of retinal drugs and the impact of the Food and Drug Administration on treatment of retinal disease must include not only an evaluation of the direct costs of the drugs and the costs associated with their administration, but also the cost savings which accrue from their clinical benefit. This chapter will discuss the financial and regulatory issues associated with retinal drugs.

  15. [Retinal vein occlusion in a young patient].

    Science.gov (United States)

    Zemba, Mihail; Ochinciuc, Uliana; Sarbu, Laura; Avram, Corina; Camburu, Raluca; Stamate, Alina

    2013-01-01

    We present a case report of a 27 years old pacient with central retinal vein occlussion and macular edema. The pacient has a significant reduction of the macular aedema with complete recovery of vision after the treatment.

  16. [Intraocular hypertension after retinal detachment surgery].

    Science.gov (United States)

    Muşat, O; Cristescu, R; Coman, Corina; Asandi, R

    2012-01-01

    This papers presents a case of a patient with retinal detachment, 3 days ago operated (posterior vitrectomy, internal tamponament with silicon oil 1000) who developed increased ocular pressure following silicon oil output in the anterior chamber.

  17. The treatment of bullous rhegmatogenous retinal detachment.

    Science.gov (United States)

    Wong, D; Chignell, A H; Inglesby, D V; Little, B C; Franks, W

    1992-01-01

    We describe the results of a consecutive series of 97 cases of bullous superior retinal detachment treated by conventional surgery. The retinal detachments were characterized by either a single retinal break or multiple retinal breaks confined within 1 clock hour and no proliferative vitreoretinopathy. The surgery involved sequential drainage of subretinal fluid, injection of air, cryotherapy and the application of local explant. All cases would otherwise be suitable for pneumatic retinopexy. The anatomical success rate was 85.5% with a single operation and 97% with further procedures. We report on the complications encountered and appraise the advantages and disadvantages of this operation. Forty-five of the 97 cases had detachment of the macula for less than 2 weeks, and 35 of the 45 (80%) achieved a visual acuity of 6/18 or better. These visual results challenge the assertion that better visual outcome might be attained with pneumatic retinopexy.

  18. [Ocular hypertension after surgery for retinal detachment].

    Science.gov (United States)

    Muşat, O; Cristescu, R; Coman, Corina; Asandi, R

    2012-01-01

    This papers presents a case of a patient with retinal detachement, 3 days ago operated (posterior vitrectomy internal tamponament with silicon oil 1000) who develop increased ocular pressure following silicon oil output in the anterior chamber.

  19. Branch retinal artery occlusion in Susac's syndrome

    Directory of Open Access Journals (Sweden)

    Ricardo Evangelista Marrocos de Aragão

    2015-02-01

    Full Text Available Susac's syndrome is a rare disease attribuited to a microangiopathy involving the arterioles of the cochlea, retina and brain. Encefalopathy, hearing loss, and visual deficits are the hallmarks of the disease. Visual loss is due to multiple, recurrent branch arterial retinal occlusions. We report a case of a 20-year-old women with Susac syndrome presented with peripheral vestibular syndrome, hearing loss, ataxia, vertigo, and vision loss due occlusion of the retinal branch artery.

  20. Current surgery of retinal detachment recurrence. Review

    Directory of Open Access Journals (Sweden)

    V. D. Zakharov

    2012-01-01

    Full Text Available this review presents a detailed analysis and an experience of surgical treatment of retinal detachment recurrence associated with light silicone oil tamponade of vitreous cavity. Approaches and variants of treatment were described in the historical aspect and till now. there are considered general and particular issues in case of retinal detachment recurrence appearance, expediency and volume of intraoperative manipulations, time of operation and choice of temporary substitute of vitreous body for a purpose of postoperative tamponade of vitreous cavity.

  1. Current surgery of retinal detachment recurrence. Review

    Directory of Open Access Journals (Sweden)

    V. D. Zakharov

    2014-07-01

    Full Text Available this review presents a detailed analysis and an experience of surgical treatment of retinal detachment recurrence associated with light silicone oil tamponade of vitreous cavity. Approaches and variants of treatment were described in the historical aspect and till now. there are considered general and particular issues in case of retinal detachment recurrence appearance, expediency and volume of intraoperative manipulations, time of operation and choice of temporary substitute of vitreous body for a purpose of postoperative tamponade of vitreous cavity.

  2. Fluid vitreous substitutes in vitreo retinal surgery

    OpenAIRE

    Saxena Sandeep; Gopal Lingam

    1996-01-01

    Advances in the surgical instrumentation and vitreoretinal techniques have allowed intraoperative reapproximation of retina to a more normal position. The use of intravitreally injected liquid materials (viscoelastic liquids, liquid perfluorocarbons and silicone oil), as adjunctive agents to vitreo-retinal surgery play an important role in facilitating retinal reattachment. These materials are used as intraoperative instruments to re-establish intraocular volume, assist in separating membrane...

  3. Complete Blood Count and Retinal Vessel Calibers

    OpenAIRE

    Gerald Liew; Jie Jin Wang; Elena Rochtchina; Tien Yin Wong; Paul Mitchell

    2014-01-01

    OBJECTIVE: The influence of hematological indices such as complete blood count on microcirculation is poorly understood. Retinal microvasculature can be directly visualized and vessel calibers are associated with a range of ocular and systemic diseases. We examined the association of complete blood count with retinal vessel calibers. METHODS: Cross-sectional population-based Blue Mountains Eye Study, n = 3009, aged 49+ years. Complete blood count was measured from fasting blood samples taken ...

  4. Intracranial Vascular Treatments

    Science.gov (United States)

    ... full size with caption Related Articles and Media Gamma Knife Linear Accelerator Catheter Embolization Angioplasty and Vascular Stenting Proton Therapy Radiation Dose in X-Ray and CT Exams Stereotactic ...

  5. Congenital Vascular Malformation

    Science.gov (United States)

    ... also be effective for small, localized birthmarks (port wine stains). Patients with a rare venous malformation (Kleppel– ... 3) non-profit organization focused on providing public education and improving awareness about vascular diseases. For more ...

  6. Melanopsin retinal ganglion cells are resistant to neurodegeneration in mitochondrial optic neuropathies

    DEFF Research Database (Denmark)

    La Morgia, C; Ross-Cisneros, F.N.; Sadun, A.A.

    2010-01-01

    Mitochondrial optic neuropathies, that is, Leber hereditary optic neuropathy and dominant optic atrophy, selectively affect retinal ganglion cells, causing visual loss with relatively preserved pupillary light reflex. The mammalian eye contains a light detection system based on a subset of retinal...... for the preservation of pupillary light reaction despite profound visual loss in patients with mitochondrial optic neuropathy, revealing the robustness of melanopsin retinal ganglion cells to a metabolic insult and opening the question of mechanisms that might protect these cells....... ganglion cells containing the photopigment melanopsin. These cells give origin to the retinohypothalamic tract and support the non-image-forming visual functions of the eye, which include the photoentrainment of circadian rhythms, light-induced suppression of melatonin secretion and pupillary light reflex...

  7. Post-cataract surgery visual disturbance in a retinitis pigmentosa patient with asteroid hyalosis.

    Science.gov (United States)

    Jingami, Yoko; Otani, Atsushi; Kojima, Hiroshi; Makiyama, Yukiko; Yoshimura, Nagahisa

    2011-05-01

    A patient with retinitis pigmentosa showed visual disturbances following successful cataract surgery. He had a dense asteroid hyalosis in the eye before cataract surgery. After the surgery he noticed that his vision became worse. The visual disturbance was explained as being caused by the progression of retinal degeneration. Although the electroretinogram was non-recordable, the degeneration of macular area appeared relatively small. We considered that dense asteroid hyalosis was responsible for his visual disturbances, and pars plana vitrectomy (PPV) was performed to remove the asteroid hyalosis. After the PPV, rapid improvement of his visual acuity was observed. Cataract surgery may affect the status of asteroid hyalosis and cause rapid visual loss. PPV should be considered for retinitis pigmentosa patients with dense asteroid hyalosis, especially when a large decrease in visual acuity is noted shortly after cataract surgery.

  8. Post-Cataract Surgery Visual Disturbance in a Retinitis Pigmentosa Patient with Asteroid Hyalosis

    Directory of Open Access Journals (Sweden)

    Yoko Jingami

    2011-08-01

    Full Text Available A patient with retinitis pigmentosa showed visual disturbances following successful cataract surgery. He had a dense asteroid hyalosis in the eye before cataract surgery. After the surgery he noticed that his vision became worse. The visual disturbance was explained as being caused by the progression of retinal degeneration. Although the electroretinogram was non-recordable, the degeneration of macular area appeared relatively small. We considered that dense asteroid hyalosis was responsible for his visual disturbances, and pars plana vitrectomy (PPV was performed to remove the asteroid hyalosis. After the PPV, rapid improvement of his visual acuity was observed. Cataract surgery may affect the status of asteroid hyalosis and cause rapid visual loss. PPV should be considered for retinitis pigmentosa patients with dense asteroid hyalosis, especially when a large decrease in visual acuity is noted shortly after cataract surgery.

  9. Retinal iron homeostasis in health and disease

    Directory of Open Access Journals (Sweden)

    Delu eSong

    2013-06-01

    Full Text Available Iron is essential for life, but excess iron can be toxic. As a potent free radical creator, iron generates hydroxyl radicals leading to significant oxidative stress. Since iron is not excreted from the body, it accumulates with age in tissues, including the retina, predisposing to age-related oxidative insult. Both hereditary and acquired retinal diseases are associated with increased iron levels. For example, retinal degenerations have been found in hereditary iron overload disorders, like aceruloplasminemia, Friedreich’s ataxia, and pantothenate kinase-associated neurodegeneration. Similarly, mice with targeted mutation of the iron exporter ceruloplasmin and its homolog hephaestin showed age-related retinal iron accumulation and retinal degeneration with features resembling human age-related macular degeneration (AMD. Post mortem AMD eyes have increased levels of iron in retina compared to age-matched healthy donors. Iron accumulation in AMD is likely to result, in part, from inflammation, hypoxia, and oxidative stress, all of which can cause iron dysregulation. Fortunately, it has been demonstrated by in vitro and in vivo studies that iron in the retinal pigment epithelium and retina is chelatable. Iron chelation protects photoreceptors and retinal pigment epithelial cells (RPE in a variety of mouse models. This has therapeutic potential for diminishing iron-induced oxidative damage to prevent or treat AMD.

  10. Diagnostic imaging in patients with retinitis pigmentosa.

    Science.gov (United States)

    Mitamura, Yoshinori; Mitamura-Aizawa, Sayaka; Nagasawa, Toshihiko; Katome, Takashi; Eguchi, Hiroshi; Naito, Takeshi

    2012-01-01

    Retinitis pigmentosa (RP) is a progressive inherited retinal disease, and patients with RP have reduced visual function caused by a degeneration of the photoreceptors and retinal pigment epithelium (RPE). At the end stage of RP, the degeneration of the photoreceptors in the fovea reduces central vision, and RP is one of the main causes of acquired blindness in developed countries. Therefore, morphological and functional assessments of the photoreceptors in the macula area can be useful in estimating the residual retinal function in RP patients. Optical coherence tomography (OCT) is a well-established method of examining the retinal architecture in situ. The photoreceptor inner/outer segment (IS/OS) junction is observed as a distinct, highly reflective line by OCT. The presence of the IS/OS junction in the OCT images is essential for normal visual function. Fundus autofluorescence (FAF) results from the accumulation of lipofuscin in the RPE cells and has been used to investigate RPE and retinal function. More than one-half of RP patients have an abnormally high density parafoveal FAF ring (AF ring). The AF ring represents the border between functional and dysfunctional retina. In this review, we shall summarize recent progress on diagnostic imaging in eyes with RP.

  11. Retinal synaptic regeneration via microfluidic guiding channels.

    Science.gov (United States)

    Su, Ping-Jung; Liu, Zongbin; Zhang, Kai; Han, Xin; Saito, Yuki; Xia, Xiaojun; Yokoi, Kenji; Shen, Haifa; Qin, Lidong

    2015-08-28

    In vitro culture of dissociated retinal neurons is an important model for investigating retinal synaptic regeneration (RSR) and exploring potentials in artificial retina. Here, retinal precursor cells were cultured in a microfluidic chip with multiple arrays of microchannels in order to reconstruct the retinal neuronal synapse. The cultured retinal cells were physically connected through microchannels. Activation of electric signal transduction by the cells through the microchannels was demonstrated by administration of glycinergic factors. In addition, an image-based analytical method was used to quantify the synaptic connections and to assess the kinetics of synaptic regeneration. The rate of RSR decreased significantly below 100 μM of inhibitor glycine and then approached to a relatively constant level at higher concentrations. Furthermore, RSR was enhanced by chemical stimulation with potassium chloride. Collectively, the microfluidic synaptic regeneration chip provides a novel tool for high-throughput investigation of RSR at the cellular level and may be useful in quality control of retinal precursor cell transplantation.

  12. [Complex vascular access].

    Science.gov (United States)

    Mangiarotti, G; Cesano, G; Thea, A; Hamido, D; Pacitti, A; Segoloni, G P

    1998-03-01

    Availability of a proper vascular access is a basic condition for a proper extracorporeal replacement in end-stage chronic renal failure. However, biological factors, management and other problems, may variously condition their middle-long term survival. Therefore, personal experience of over 25 years has been critically reviewed in order to obtain useful information. In particular "hard" situations necessitating complex procedures have been examined but, if possible, preserving the peripherical vascular features.

  13. Ageing and vascular ageing

    OpenAIRE

    2006-01-01

    There is an age related decline in various physiological processes. Vascular ageing is associated with changes in the mechanical and the structural properties of the vascular wall, which leads to the loss of arterial elasticity and reduced arterial compliance. Arterial compliance can be measured by different parameters like pulse wave velocity, augmentation index, and systemic arterial compliance. There is evidence that arterial compliance is reduced in disease states such as hypertension, di...

  14. Functions of Müller cell-derived vascular endothelial growthfactor in diabetic retinopathy

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    Müller cells are macroglia and play many essentialroles as supporting cells in the retina. To respond topathological changes in diabetic retinopathy (DR), amajor complication in the eye of diabetic patients,retinal Müller glia produce a high level of vascularendothelial growth factor (VEGF or VEGF-A). As VEGFis expressed by multiple retinal cell-types and Müllerglia comprise only a small portion of cells in the retina,it has been a great challenge to reveal the function ofVEGF or other globally expressed proteins produced byMüller cells. With the development of conditional genetargeting tools, it is now possible to dissect the functionof Müller cell-derived VEGF in vivo . By using conditionalgene targeting approach, we demonstrate that Müllerglia are a major source of retinal VEGF in diabetic miceand Müller cell-derived VEGF plays a significant role inthe alteration of protein expression and peroxynitration,which leads to retinal inflammation, neovascularization,vascular leakage, and vascular lesion, key pathologicalchanges in DR. Therefore, Müller glia are a potentialcellular target for the treatment of DR, a leading causeof blindness.

  15. Ustilago maydis accumulates beta-carotene at levels determined by a retinal-forming carotenoid oxygenase.

    Science.gov (United States)

    Estrada, Alejandro F; Brefort, Thomas; Mengel, Carina; Díaz-Sánchez, Violeta; Alder, Adrian; Al-Babili, Salim; Avalos, Javier

    2009-10-01

    The basidiomycete Ustilago maydis, the causative agent of corn smut disease, has emerged as a model organism for dimorphism and fungal phytopathogenicity. In this work, we line out the key conserved enzymes for beta-carotene biosynthesis encoded by the U. maydis genome and show that this biotrophic fungus accumulates beta-carotene. The amount of this pigment depended on culture pH and aeration but was not affected by light and was not increased by oxidative stress. Moreover, we identified the U. maydis gene, cco1, encoding a putative beta-carotene cleavage oxygenase. Heterologous overexpression and in vitro analyses of purified enzyme demonstrated that Cco1 catalyzes the symmetrical cleavage of beta-carotene to yield two molecules of retinal. Analyses of beta-carotene and retinal contents in U. maydiscco1 deletion and over-expression strains confirmed the enzymatic function of Cco1, and revealed that Cco1 determines the beta-carotene content. Our data indicate that carotenoid biosynthesis in U. maydis is carried out to provide retinal rather than to deliver protective pigments. The U. maydis genome also encodes three potential opsins, a family of photoactive proteins that use retinal as chromophore. Two opsin genes showed different light-regulated expression patterns, suggesting specialized roles in photobiology, while no mRNA was detected for the third opsin gene in the same experiments. However, deletion of the cco1 gene, which should abolish function of all the retinal-dependent opsins, did not affect growth, morphology or pathogenicity, suggesting that retinal and opsin proteins play no relevant role in U. maydis under the tested conditions.

  16. Role of Transthoracic Echocardiography in the Evaluation of Patients with Retinal Vein Occlusion

    Directory of Open Access Journals (Sweden)

    Afsoon Fazlinezhad

    2014-02-01

    Full Text Available Introduction: Retinal vein occlusion  is a common vascular disorder disrupting vision. Two basic types of RVO are branch retinal vein occlusion and central retinal vein occlusion (CRVO.  Retinal vein occlusion is a multifactor process including systemic illness and local retinal factors.RVO may be associated with atherosclerotic risk factors. We analyzed the role of 2 dimensional transthoracic echocardiography (TTE for detecting the cardiac disease in patients with retinal veins occlusion. Materials and Methods:In this cross-sectional study 70 recently diagnosed patients with RVO enrolled in the study. The clinical diagnosis of retinal vein occlusion and its type was confirmed by a vitreoretinal specialist. The Patients were then referred for performing complete TTE. Results: The prevalence of RVO increased with age, but did not vary by sex. The most frequent cardiovascular risk factor was hypertension. The findings of our study revealed that a variety of echocardiographic abnormalities may be presented in patients with RVO. Diastolic dysfunction was the most frequent echocardiographic finding and we found positive correlation between diastolic dysfunction with increasing age and the presence of hypertension. Other findings included mitral regurgitation (52.9%, mitral stenosis (2.9%, mitral annulus calcification (1.4%, mitral valve prolapse (8.6%, aortic insufficiency (22.9%, sclerotic aortic valve (27.1%, tricuspid regurgitation (45.7%, pulmonary insufficiency (8.6%, mild pulmonary hypertension (8.6%, and moderate to severe pulmonary hypertension (4.3% Mild LVH (11.4%, Moderate LVH (8.6%. Abnormality on IAS was defined in these patients, including paten foramen ovale, lipomatosis IAS, exaggerated motion of IAS, and aneurysm of IAS. Conclusion: In our study, the most common echocardiographic finding was diastolic dysfunction which was compatible with the patients' age and the fact that the most prevalent risk factor was hypertension. Other

  17. Arterial stiffness, as monitored by cardio–ankle vascular index, is affected by obstructive sleep apnea, blood glucose control, and body weight – a case with 8 years follow up

    Directory of Open Access Journals (Sweden)

    Shimizu K

    2016-08-01

    Full Text Available Kazuhiro Shimizu,1 Tomoyuki Yamamoto,2,3 Kohji Shirai2,4 1Department of Internal Medicine, Toho University Sakura Medical Center, Chiba, Japan; 2Department of Vascular Function, Toho University Sakura Medical Center, Chiba, Japan; 3Biological Information Analysis Section, Fukuda Denshi Co., Ltd., Tokyo, Japan; 4Department of Internal Medicine, Mihama Hospital, Chiba, Japan Abstract: The cardio–ankle vascular index (CAVI is an indicator of arterial stiffness from the heart to the ankles. The CAVI increases as arteriosclerosis progresses, but it can be decreased by appropriate treatment. There are several risk factors for coronary artery disease, however, the degree of stress caused by each separate risk factor to arteries cannot be assessed. CAVI increases with age and according to the severity of atherosclerosis. We found that CAVI also changes in response to the control of risk factors, which may be associated with the functional stiffness of arteries. CAVI can be a useful indicator of risk control for coronary artery disease. We followed a patient aged 71 years who had diabetes mellitus and obstructive sleep apnea (OSA by measuring CAVI for 8 years from age 63. He underwent coronary artery bypass grafting due to angina pectoris when he was 63 years old. Before coronary artery bypass grafting, CAVI was 11.8 on the right and 11.5 on the left. Three years later he was found to have OSA and received treatment with continuous positive airway pressure. There was a marked improvement in CAVI after continuous positive airway pressure (age 68; right 10.4, left 10.2. However, following a gradual increase in body weight and worsening of diabetes mellitus, CAVI showed an increasing trend. CAVI decreased with biguanides treatment, but increased again with an increase in body weight. In conclusion, CAVI responded to the patient’s conditions including obesity, diabetes mellitus, and OSA. CAVI is not only a marker of arterial stiffness, but can also be a

  18. Metabolic bone disease and central retinal degeneration in a kitten due to nutritional inadequacy of an all-meat raw diet

    Directory of Open Access Journals (Sweden)

    Catherine Lenox

    2015-05-01

    Full Text Available A 5-month-old castrated male Sphynx kitten presented with left hindlimb lameness shortly after adoption. Prior to adoption, the breeder had fed the kitten an exclusively raw chicken diet. Radiographs revealed generalized osteopenia and a left tibia–fibula fracture. Ophthalmic examination revealed corneal vascularization and opacity in the right eye, and lesions suggestive of feline central retinal degeneration in the left eye. The patient’s diagnoses included metabolic bone disease and feline central retinal degeneration, which can result from taurine deficiency. The kitten’s nutritional diseases were managed with a complete and balanced canned diet designed for kitten growth and with taurine supplementation.

  19. Vascular and avascular retinae in mammals. A funduscopic and fluorescein angiographic study.

    Science.gov (United States)

    Buttery, R G; Haight, J R; Bell, K

    1990-01-01

    Intraretinal blood vessels are present in some and absent in other vertebrate species, including the mammals. Among the marsupials, both vascular and avascular retinae are seen. We determined the funduscopic appearance of the eye, investigated the functional aspects of ocular blood flow in both types of retina in marsupials and compared our results with known patterns in placental mammals. The Australian polyprotodont marsupials, the Tasmanian devil, Sarcophilus harrisii, and the quoll, Dasyurus viverrinus, together with an American polyprotodont, the Virginia opossum, Didelphis virginiana, demonstrate variable degrees of tapetal differentiation, pigmentation and a very close parallel course of their intraretinal arteries and veins over considerable distances. Using the technique of fluorescein angiography, we found that retinal blood flow in the 3 vascular Australian species commenced with arterial filling. Early venous was seen next, followed by the capillary blush. This unusual sequence of vascular flow differs from that of the arterial-capillary-venous filling seen in placental mammals. This difference is most likely a consequence of the known looped, end artery organisation found within marsupial nervous systems, of which the retinae are a part. The 2 diprotodont marsupials examined, the brushtail possum, Trichosurus vulpecula, and the sugar glider, Petaurus breviceps, possess avascular retinae. Only a small residual tuft of fluorescein-impermeable vessels projects from the optic disc into the vitreous. Interestingly, the structural complexity of the central visual system in diprotodonts all of whom possess avascular retinae) is commonly accepted as being greater than that of the stem polyprotodont line (which possess vascular retinae). If retinal function matches this internal complexity, then retinal avascularity may, as in birds, be associated with superior vision. However, as the retinae of these mammals clearly lack any nutritive mechanisms directly

  20. Advanced Coats’ disease treated with intravitreal bevacizumab combined with laser vascular ablation

    OpenAIRE

    Villegas VM; Gold AS; Berrocal AM; Murray TG

    2014-01-01

    Victor M Villegas,1 Aaron S Gold,1 Audina M Berrocal,2 Timothy G Murray11Ocular Oncology and Retina, Miami, FL, USA; 2Department of Ophthalmology, Bascom Palmer Eye Institute, Miller School of Medicine, University of Miami, Miami, FL, USAPurpose: To evaluate the impact of intravitreal bevacizumab combined with laser vascular ablation in the management of advanced Coats’ disease presenting with exudative retinal detachment.Methods: This was a retrospective review of 24 child...

  1. Inhibition of APE1/Ref-1 redox activity with APX3330 blocks retinal angiogenesis in vitro and in vivo.

    Science.gov (United States)

    Jiang, Aihua; Gao, Hua; Kelley, Mark R; Qiao, Xiaoxi

    2011-01-01

    This study examines the role of APE1/Ref-1 in the retina and its potential as a therapeutic target for inhibiting retinal angiogenesis. APE1/Ref-1 expression was quantified by Western blot. The role of APE1/Ref-1 redox function in endothelial cell in vitro angiogenesis was examined by treating retinal vascular endothelial cells (RVECs) with APX3330, a small molecule inhibitor of APE1/Ref-1 redox activity. In vitro methods included a proliferation assay, a transwell migration assay, a Matrigel tube formation assay, and a Real-Time Cell Analysis (RTCA) using the xCELLigence System. In vivo functional studies of APE1/Ref-1 were carried out by treating very low density lipoprotein (VLDL) receptor knockout mice (Vldlr(-/-)) with intravitreal injection of APX3330, and subsequent measurement of retinal angiomatous proliferation (RAP)-like neovascularization for one week. APE1/Ref-1 was highly expressed in the retina and in RVECs and pericytes in mice. APX3330 (1-10 μM) inhibited proliferation, migration and tube formation of RVECs in vitro in a dose-dependent manner. Vldlr(-/-) RVECs were more sensitive to APX3330 than wild-type RVECs. In Vldlr(-/-) mice, a single intravitreal injection of APX3330 at the onset of RAP-like neovascularization significantly reduced RAP-like neovascularization development. APE1/Ref-1 is expressed in retinal vascular cells. APX3330 inhibits RVEC angiogenesis in vitro and significantly reduces RAP-like neovascularization in Vldlr(-/-) mice. These data support the conclusion that APE1/Ref-1 redox function is required for retinal angiogenesis. Thus, APE1/Ref-1 may have potential as a therapeutic target for treating neovascular age-related macular degeneration and other neovascular diseases.

  2. Animals deficient in C2Orf71, an autosomal recessive retinitis pigmentosa-associated locus, develop severe early-onset retinal degeneration.

    Science.gov (United States)

    Kevany, Brian M; Zhang, Ning; Jastrzebska, Beata; Palczewski, Krzysztof

    2015-05-01

    Genetic mapping was recently used to identify the underlying cause for a previously uncharacterized cohort of autosomal recessive retinitis pigmentosa cases. Genetic mapping of affected individuals resulted in the identification of an uncharacterized gene, C2Orf71, as the causative locus. However, initial homology searches failed to reveal similarities to any previously characterized protein or domain. To address this issue, we characterized the mouse homolog, BC027072. Immunohistochemistry with a custom polyclonal antibody showed staining localized to the inner segments (IS) of photoreceptor cells, as well as the outer segments (OS) of cone cells. A knockout mouse line (BC(-/-)) was generated and demonstrated that loss of this gene results in a severe, early-onset retinal degeneration. Histology and electron microscopy (EM) revealed disorganized OS as early as 3 weeks with complete loss by 24 weeks of age. EM micrographs displayed packets of cellular material containing OS discs or IS organelles in the OS region and abnormal retinal pigmented epithelium cells. Analyses of retinoids and rhodopsin levels showed retinal degenerations. Although its function remains unknown, this protein appears essential for normal OS development/maintenance and vision in humans and mice. RNAseq data are available in the GEO database under accession: GSE63810.

  3. Combined central retinal artery and vein occlusion secondary to systemic non-Hodgkin′s lymphoma

    Directory of Open Access Journals (Sweden)

    Shukla Dhananjay

    2006-01-01

    Full Text Available We report a rare case of low-grade systemic B-cell non-Hodgkin′s lymphoma (NHL causing central retinal artery and vein occlusion, which was the only manifestation of disease recurrence. A young man with resolved systemic NHL underwent fluorescein angiography, magnetic resonance imaging and computed tomography to investigate a severe unilateral visual loss. A combined vascular occlusion was observed in the right eye. Neuroimaging detected optic nerve infiltration; but no systemic/ central nervous system involvement was observed. The patient was treated with high-doses of corticosteroids and optic nerve irradiation. The optic neuropathy and vascular occlusion were resistant to treatment. The subsequent neovascular glaucoma was treated by panretinal photocoagulation, which relieved the pain, but vision was not recovered. No further recurrence was observed over the following year.

  4. Retrograde degeneration of retinal ganglion cells in homonymous hemianopsia

    Directory of Open Access Journals (Sweden)

    Herro AM

    2015-06-01

    Full Text Available Angela M Herro, Byron L Lam Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, FL, USA Background: The aim of this study was to demonstrate the relationship between topographic reduction in macular ganglion cell complex (GCC thickness as detected with spectral-domain optical coherence tomography and visual field defects caused by ischemic occipital cortical injury.Methods: This study was a retrospective review of all patients who presented to our eye institution between January 2012 and July 2014 with visual field defects secondary to ischemic cortical injury. The visual field defect pattern and mean deviation were analyzed. Retinal nerve fiber layer (RNFL and macular GCC were both assessed with spectral-domain optical coherence tomography. Patients with any ocular pathology that could affect these measurements were excluded. The topographic relationship of visual field defect to reduction in GCC was specifically analyzed. Results: Nine patients met the inclusion criteria. Their average age was 65 (57–73 years; eight were men and six had right hemianopsias. The laterality of the visual field defect was used to assign an affected and unaffected side of analysis for RNFL and GCC layer thickness. A right hemianopsia meant that the nasal fibers of the right eye and temporal fibers of the left eye were assigned as the “affected side”, and the temporal fibers of the right eye and nasal fibers of the left eye were assigned as “unaffected”. There was no statistically significant difference between affected and unaffected RNFL. However, there was a significant difference in GCC layer reduction between the affected and unaffected sides (P=0.029.Conclusion: There is evidence of retrograde trans-synaptic retinal ganglion cell loss in patients with homonymous hemianopsias from cortical visual impairment. This relationship is reflected in thinning of the GCC and maintains the topographic

  5. Psoriasis and vascular disease: an unsolved mystery.

    Science.gov (United States)

    Shelling, Michael L; Federman, Daniel G; Prodanovich, Srdjan; Kirsner, Robert S

    2008-05-01

    Psoriasis is an immune disease most commonly recognized for its skin and joint manifestations. These produce significant physical, social, and psychological distress in affected patients and resultant reductions in their quality of life. As expected, these concerns are vital in providing symptomatic improvement and in selecting an individualized therapy. Yet, the approach in management of these patients is likely to change given the growing body of evidence linking psoriasis and vascular disease. Stemming from an anecdotally described relationship, the association between psoriasis and vascular disease has become a focus of current research to further elucidate the pathophysiology underlying and connecting these two diseases. This article includes a review of the classical cardiovascular risk factors, the atherothrombotic markers, and the environmental stressors associated with psoriasis, as well as a critical review of the observed vascular diseases, the proposed mechanism of atherosclerosis, and the benefits of treatment of psoriasis.

  6. Chemokine mediated monocyte trafficking into the retina: role of inflammation in alteration of the blood-retinal barrier in diabetic retinopathy.

    Directory of Open Access Journals (Sweden)

    Sampathkumar Rangasamy

    Full Text Available Inflammation in the diabetic retina is mediated by leukocyte adhesion to the retinal vasculature and alteration of the blood-retinal barrier (BRB. We investigated the role of chemokines in the alteration of the BRB in diabetes. Animals were made diabetic by streptozotocin injection and analyzed for gene expression and monocyte/macrophage infiltration. The expression of CCL2 (chemokine ligand 2 was significantly up-regulated in the retinas of rats with 4 and 8 weeks of diabetes and also in human retinal endothelial cells treated with high glucose and glucose flux. Additionally, diabetes or intraocular injection of recombinant CCL2 resulted in increased expression of the macrophage marker, F4/80. Cell culture impedance sensing studies showed that purified CCL2 was unable to alter the integrity of the human retinal endothelial cell barrier, whereas monocyte conditioned medium resulted in significant reduction in cell resistance, suggesting the relevance of CCL2 in early immune cell recruitment for subsequent barrier alterations. Further, using Cx3cr1-GFP mice, we found that intraocular injection of CCL2 increased retinal GFP+ monocyte/macrophage infiltration. When these mice were made diabetic, increased infiltration of monocytes/macrophages was also present in retinal tissues. Diabetes and CCL2 injection also induced activation of retinal microglia in these animals. Quantification by flow cytometry demonstrated a two-fold increase of CX3CR1+/CD11b+ (monocyte/macrophage and microglia cells in retinas of wildtype diabetic animals in comparison to control non-diabetic ones. Using CCL2 knockout (Ccl2-/- mice, we show a significant reduction in retinal vascular leakage and monocyte infiltration following induction of diabetes indicating the importance of this chemokine in alteration of the BRB. Thus, CCL2 may be an important therapeutic target for the treatment of diabetic macular edema.

  7. Melanopsin retinal ganglion cell loss in Alzheimer's disease

    DEFF Research Database (Denmark)

    La Morgia, Chiara; Ross-Cisneros, Fred N; Koronyo, Yosef

    2015-01-01

    OBJECTIVE: Melanopsin retinal ganglion cells (mRGCs) are photoreceptors driving circadian photoentrainment, and circadian dysfunction characterizes Alzheimer's disease (AD). We investigated mRGCs in AD, hypothesizing their contribution to circadian dysfunction. METHODS: We assessed retinal nerve...

  8. Genetics Home Reference: neuropathy, ataxia, and retinitis pigmentosa

    Science.gov (United States)

    ... Me Understand Genetics Home Health Conditions NARP neuropathy, ataxia, and retinitis pigmentosa Enable Javascript to view the ... Download PDF Open All Close All Description Neuropathy, ataxia, and retinitis pigmentosa ( NARP ) is a condition that ...

  9. Retinal Vessel Segmentation Using A New Topological Method

    CERN Document Server

    Brooks, Martin

    2016-01-01

    A novel topological segmentation of retinal images represents blood vessels as connected regions in the continuous image plane, having shape-related analytic and geometric properties. This paper presents topological segmentation results from the DRIVE retinal image database.

  10. Protein Kinase C Inhibitors as Modulators of Vascular Function and Their Application in Vascular Disease

    Directory of Open Access Journals (Sweden)

    Raouf A. Khalil

    2013-03-01

    Full Text Available Blood pressure (BP is regulated by multiple neuronal, hormonal, renal and vascular control mechanisms. Changes in signaling mechanisms in the endothelium, vascular smooth muscle (VSM and extracellular matrix cause alterations in vascular tone and blood vessel remodeling and may lead to persistent increases in vascular resistance and hypertension (HTN. In VSM, activation of surface receptors by vasoconstrictor stimuli causes an increase in intracellular free Ca2+ concentration ([Ca2+]i, which forms a complex with calmodulin, activates myosin light chain (MLC kinase and leads to MLC phosphorylation, actin-myosin interaction and VSM contraction. Vasoconstrictor agonists could also increase the production of diacylglycerol which activates protein kinase C (PKC. PKC is a family of Ca2+-dependent and Ca2+-independent isozymes that have different distributions in various blood vessels, and undergo translocation from the cytosol to the plasma membrane, cytoskeleton or the nucleus during cell activation. In VSM, PKC translocation to the cell surface may trigger a cascade of biochemical events leading to activation of mitogen-activated protein kinase (MAPK and MAPK kinase (MEK, a pathway that ultimately increases the myofilament force sensitivity to [Ca2+]i, and enhances actin-myosin interaction and VSM contraction. PKC translocation to the nucleus may induce transactivation of various genes and promote VSM growth and proliferation. PKC could also affect endothelium-derived relaxing and contracting factors as well as matrix metalloproteinases (MMPs in the extracellular matrix further affecting vascular reactivity and remodeling. In addition to vasoactive factors, reactive oxygen species, inflammatory cytokines and other metabolic factors could affect PKC activity. Increased PKC expression and activity have been observed in vascular disease and in certain forms of experimental and human HTN. Targeting of vascular PKC using PKC inhibitors may function in

  11. Progressive outer retinal necrosis syndrome: a comprehensive review of its clinical presentation, relationship to immune system status, and management.

    Science.gov (United States)

    Austin

    2000-12-01

    Progressive outer retinal necrosis (PORN) syndrome is a form of the Varicella zoster virus (VZV) chorioretinitis found almost exclusively in people with the acquired immunodeficiency syndrome (AIDS). This destructive infection has an extremely rapid course that may lead to no light perception in affected eyes within days or weeks. Attempts at its treatment have had limited success. Rhegmatogenous retinal detachments often occur after the development of atrophic retinal holes, and silicone oil temponade has been found to be the most successful reattachment procedure. Unfortunately, cataract formation is common after such surgery. PORN needs to be differentiated from acute retinal necrosis (ARN) syndrome, a necrotizing retinitis that can also be caused by VZV. PORN and ARN are found at opposite ends of the spectrum of necrotizing herpetic retinopathies (NHR), where its clinical presentation depends upon immune system status. After a brief case presentation, the distinguishing clinical characteristics of PORN, its differentiation from ARN, attempts at its treatment, the role of the immune system status on its clinical appearance and treatment, and management of complications such as retinal detachment and subsequent cataracts are discussed.

  12. Ageing and vascular ageing

    Science.gov (United States)

    Jani, B; Rajkumar, C

    2006-01-01

    There is an age related decline in various physiological processes. Vascular ageing is associated with changes in the mechanical and the structural properties of the vascular wall, which leads to the loss of arterial elasticity and reduced arterial compliance. Arterial compliance can be measured by different parameters like pulse wave velocity, augmentation index, and systemic arterial compliance. There is evidence that arterial compliance is reduced in disease states such as hypertension, diabetes, and end stage renal failure. Changes in arterial compliance can be present before the clinical manifestation of cardiovascular disease. Pharmacological and non‐pharmacological measures have been shown to improve arterial compliance. Arterial compliance may constitute an early cardiovascular risk marker and may be useful in assessing the effects of drugs on the cardiovascular system. Pharmacogenetics and genetics of arterial compliance in the future will improve our knowledge and understanding about vascular ageing. PMID:16754702

  13. Stem Cell Therapies in Retinal Disorders

    Directory of Open Access Journals (Sweden)

    Aakriti Garg

    2017-02-01

    Full Text Available Stem cell therapy has long been considered a promising mode of treatment for retinal conditions. While human embryonic stem cells (ESCs have provided the precedent for regenerative medicine, the development of induced pluripotent stem cells (iPSCs revolutionized this field. iPSCs allow for the development of many types of retinal cells, including those of the retinal pigment epithelium, photoreceptors, and ganglion cells, and can model polygenic diseases such as age-related macular degeneration. Cellular programming and reprogramming technology is especially useful in retinal diseases, as it allows for the study of living cells that have genetic variants that are specific to patients’ diseases. Since iPSCs are a self-renewing resource, scientists can experiment with an unlimited number of pluripotent cells to perfect the process of targeted differentiation, transplantation, and more, for personalized medicine. Challenges in the use of stem cells are present from the scientific, ethical, and political realms. These include transplant complications leading to anatomically incorrect placement, concern for tumorigenesis, and incomplete targeting of differentiation leading to contamination by different types of cells. Despite these limitations, human ESCs and iPSCs specific to individual patients can revolutionize the study of retinal disease and may be effective therapies for conditions currently considered incurable.

  14. Retinal haemorrhages in vacuum extraction deliveries

    Directory of Open Access Journals (Sweden)

    Bahgat Mostafa

    1987-01-01

    Full Text Available Two hundred and thirty eight newly born infants were subjected to fundus examination in the first 5 hours of labour then daily till discharge from the hospital then weekly till complete absorption of retinal haemorrhages The 238 infants were 23 delivered by caesarean section, 90 with spontaneous vaginal delivery,45 babies (over3.5 kgm delivered vaginallyand80 delivered by vacuum extraction. It was found that 37.39% of the newborns had retinal haemorrhages. The incidence, type and severity of retinal haemorrhages were related to the extent of obstetric trauma during birth. They were least with caesarean section. (4.35%, more in babies with spontaneous vaginal delivery (20%, more higher in infants over 3.5 kgm birth weight (33.33% and maximum in vacuum extraction deliveries (68.75%. A good correlation was made between the site and duration of cup application, level and rate of increase of negative pressure, the presence and size of cephalhematoma and the incidence and severity of retinal haemorrhages A good choice of cases as well as good control of the technique of vacuum extraction will minimize the incidence and severity of retinal haemorrhages in the new born.

  15. External Approach Microsurgery of Retinal Dialysis

    Institute of Scientific and Technical Information of China (English)

    Ying Zhang; Piqing Hu; Lixin Shun; Xuechun Zhu; Yingwu Yi; Wen Liu

    2005-01-01

    Purpose: To explore the effect of external approach microsurgery in retinal dialysis.Methods: Consecutive 30 eyes of 28 patients with retinal dialysis were enrolled for this study. The progresses of the external approach microsurgery were following. Under the surgical microscopy, the preplacement of mattress sutures for buckling and/or encircling following retrobulbar anesthesia and scleral exposure, draining subretinal fluid, the cryotherapy of retinal breaks, checking the position of breaks on scleral buckle and gases injection were performed in turn.Results: After drainage of subretinal fluid, with scleral depression cryotherapy reaction around breaks could be observed clearly under the microscopy. All breaks were located on anterior slope of the buckle. Intraoperative complications were mild subretinal hemorrhage at drainage site and corneal epithelium exfoliation in 3 eyes, respectively.Postoperative complications were mainly secondary glaucoma and retinal redetachment.The one-operation reattachmentl rate was 96.7% (29 eyes), and the final reattachment rate was 100% after one eye had a second external approach microsurgery. The postoperative vision acuity (VA) was significantly better than the preoperative VA (X2=9.529, P< 0.01).Conclusion: External approach microsurgery has favourable effect on the surgery of retinal dialysis.

  16. MR detection of retinal hemorrhages: correlation with graded ophthalmologic exam

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    Beavers, Angela J.; Allbery, Sandra M. [University of Nebraska Medical Center, Department of Radiology, Omaha, NE (United States); Children' s Hospital and Medical Center, Department of Radiology, Omaha, NE (United States); Stagner, Anna M.; Hejkal, Thomas W. [University of Nebraska Medical Center, Department of Ophthalmology, Omaha, NE (United States); Children' s Hospital and Medical Center, Department of Ophthalmology, Omaha, NE (United States); Lyden, Elizabeth R. [University of Nebraska Medical Center, College of Public Health, Omaha, NE (United States); Haney, Suzanne B. [Children' s Hospital and Medical Center, Department of Pediatrics, Omaha, NE (United States); University of Nebraska Medical Center, Department of Pediatrics, Omaha, NE (United States)

    2015-08-15

    Dilated fundoscopic exam is considered the gold standard for detecting retinal hemorrhage, but expertise in obtaining this exam is not always immediately available. MRI can detect retinal hemorrhages, but correlation of the grade or severity of retinal hemorrhage on dilated fundoscopic exam with retinal hemorrhage visibility on MRI has not been described. To determine the value of standard brain protocol MRI in detecting retinal hemorrhage and to determine whether there is any correlation with MR detection of retinal hemorrhage and the dilated fundoscopic exam grade of hemorrhage. We conducted a retrospective chart review of 77 children <2 years old who were seen for head trauma from April 2007 to July 2013 and had both brain MRI and dilated fundoscopic exam or retinal camera images. A staff pediatric radiologist and radiology resident reviewed the MR images. Retinal hemorrhages were graded by a chief ophthalmology resident on a 12-point scale based on the retinal hemorrhage type, size, location and extent as seen on review of retinal camera images and detailed reports by ophthalmologists. Higher scores indicated increased severity of retinal hemorrhages. There was a statistically significant difference in the median grade of retinal hemorrhage examination between children who had retinal hemorrhage detected on MRI and children who did not have retinal hemorrhage detected on MRI (P = 0.02). When examination grade was categorized as low-grade (1-4), moderate-grade (5-8) or high-grade (>8) hemorrhage, there was a statistically significant association between exam grade and diagnosis based on MRI (P = 0.008). For example, only 14% of children with low-grade retinal hemorrhages were identified on MRI compared to 76% of children with high-grade hemorrhages. MR detection of retinal hemorrhage demonstrated a sensitivity of 61%, specificity of 100%, positive predictive value of 100% and negative predictive value of 63%. Retinal hemorrhage was best seen on the gradient

  17. Generation of retinal pigment epithelial cells from human embryonic stem cell-derived spherical neural masses.

    Science.gov (United States)

    Cho, Myung Soo; Kim, Sang Jin; Ku, Seung-Yup; Park, Jung Hyun; Lee, Haksup; Yoo, Dae Hoon; Park, Un Chul; Song, Seul Ae; Choi, Young Min; Yu, Hyeong Gon

    2012-09-01

    Dysfunction and loss of retinal pigment epithelium (RPE) are major pathologic changes observed in various retinal degenerative diseases such as aged-related macular degeneration. RPE generated from human pluripotent stem cells can be a good candidate for RPE replacement therapy. Here, we show the differentiation of human embryonic stem cells (hESCs) toward RPE with the generation of spherical neural masses (SNMs), which are pure masses of hESCs-derived neural precursors. During the early passaging of SNMs, cystic structures arising from opened neural tube-like structures showed pigmented epithelial morphology. These pigmented cells were differentiated into functional RPE by neuroectodermal induction and mechanical purification. Most of the differentiated cells showed typical RPE morphologies, such as a polygonal-shaped epithelial monolayer, and transmission electron microscopy revealed apical microvilli, pigment granules, and tight junctions. These cells also expressed molecular markers of RPE, including Mitf, ZO-1, RPE65, CRALBP, and bestrophin. The generated RPE also showed phagocytosis of isolated bovine photoreceptor outer segment and secreting pigment epithelium-derived factor and vascular endothelial growth factor. Functional RPE could be generated from SNM in our method. Because SNMs have several advantages, including the capability of expansion for long periods without loss of differentiation capability, easy storage and thawing, and no need for feeder cells, our method for RPE differentiation may be used as an efficient strategy for generating functional RPE cells for retinal regeneration therapy.

  18. Mosaic of the Curved Human Retinal Images Based on the Scale-Invariant Feature Transform

    Institute of Scientific and Technical Information of China (English)

    LI Ju-peng; CHEN Hou-jin; ZHANG Xin-yuan; YAO Chang

    2008-01-01

    .To meet the needs in the fundus examination, including outlook widening, pathology tracking, etc., this paper describes a robust feature-based method for fully-automatic mosaic of the curved human retinal images photographed by a fundus microscope. The kernel of this new algorithm is the scale-, rotation-and illumination-invariant interest point detector & feature descriptor-Scale-Invariant Feature Transform. When matched interest points according to second-nearest-neighbor strategy, the parameters of the model are estimated using the correct matches of the interest points,extracted by a new inlier identification scheme based on Sampson distance from putative sets. In order to preserve image features, bilinear warping and multi-band blending techniques are used to create panoramic retinal images. Experiments show that the proposed method works well with rejection error in 0.3 pixels, even for those cases where the retinal images without discernable vascular structure in contrast to the state-of-the-art algorithms.

  19. The effects of dietary carotenoid supplementation and retinal carotenoid accumulation on vision-mediated foraging in the house finch.

    Directory of Open Access Journals (Sweden)

    Matthew B Toomey

    Full Text Available BACKGROUND: For many bird species, vision is the primary sensory modality used to locate and assess food items. The health and spectral sensitivities of the avian visual system are influenced by diet-derived carotenoid pigments that accumulate in the retina. Among wild House Finches (Carpodacus mexicanus, we have found that retinal carotenoid accumulation varies significantly among individuals and is related to dietary carotenoid intake. If diet-induced changes in retinal carotenoid accumulation alter spectral sensitivity, then they have the potential to affect visually mediated foraging performance. METHODOLOGY/PRINCIPAL FINDINGS: In two experiments, we measured foraging performance of house finches with dietarily manipulated retinal carotenoid levels. We tested each bird's ability to extract visually contrasting food items from a matrix of inedible distracters under high-contrast (full and dimmer low-contrast (red-filtered lighting conditions. In experiment one, zeaxanthin-supplemented birds had significantly increased retinal carotenoid levels, but declined in foraging performance in the high-contrast condition relative to astaxanthin-supplemented birds that showed no change in retinal carotenoid accumulation. In experiments one and two combined, we found that retinal carotenoid concentrations predicted relative foraging performance in the low- vs. high-contrast light conditions in a curvilinear pattern. Performance was positively correlated with retinal carotenoid accumulation among birds with low to medium levels of accumulation (∼0.5-1.5 µg/retina, but declined among birds with very high levels (>2.0 µg/retina. CONCLUSION/SIGNIFICANCE: Our results suggest that carotenoid-mediated spectral filtering enhances color discrimination, but that this improvement is traded off against a reduction in sensitivity that can compromise visual discrimination. Thus, retinal carotenoid levels may be optimized to meet the visual demands of specific

  20. Diagnosing vascular causes of renal failure.

    Science.gov (United States)

    Abuelo, J G

    1995-10-15

    The incidence of renal failure due to vascular diseases is increasing. Two reasons for this are the epidemic of atherosclerotic vascular disease in the aging population and the widespread use of vasoactive drugs that can adversely affect renal function. These vascular causes of renal failure include vasomotor disorders such as that associated with nonsteroidal antiinflammatory drugs, small-vessel diseases such as cholesterol crystal embolization, and large-vessel diseases such as renal artery stenosis. These causes of azotemia are less familiar to physicians than more classic causes, such as acute tubular necrosis, and are less likely to be recognized in their early stages. This article describes the various vascular diseases that impair renal function and outlines the steps necessary to identify them. Although some of these conditions, such as renal artery stenosis, can gradually impair function, the vascular causes of acute renal failure are emphasized in this article. Because the vasculitides primarily cause renal failure through secondary glomerulonephritis, they are mentioned only briefly. Extensive testing is rarely necessary because the cause is usually suspected through syndrome recognition. The diagnosis can then be confirmed by the results of one or two additional tests or by improved renal function after treatment.