WorldWideScience

Sample records for affecting retinal vascular

  1. Diabetes and Retinal Vascular Dysfunction

    Directory of Open Access Journals (Sweden)

    Eui Seok Shin

    2014-01-01

    Full Text Available Diabetes predominantly affects the microvascular circulation of the retina resulting in a range of structural changes unique to this tissue. These changes ultimately lead to altered permeability, hyperproliferation of endothelial cells and edema, and abnormal vascularization of the retina with resulting loss of vision. Enhanced production of inflammatory mediators and oxidative stress are primary insults with significant contribution to the pathogenesis of diabetic retinopathy (DR. We have determined the identity of the retinal vascular cells affected by hyperglycemia, and have delineated the cell autonomous impact of high glucose on function of these cells. We discuss some of the high glucose specific changes in retinal vascular cells and their contribution to retinal vascular dysfunction. This knowledge provides novel insight into the molecular and cellular defects contributing to the development and progression of diabetic retinopathy, and will aid in the development of innovative, as well as target specific therapeutic approaches for prevention and treatment of DR.

  2. 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.

  3. 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...... (VEGF) in retinal ischemia. Retinal ischemia was induced in porcine eyes by applying an intraocular pressure, followed by 12 h of reperfusion. HIF-1α mRNA expression was not affected by ischemia, while immunofluorescence staining was higher after ischemia in the neuroretina. HIF-1β immunoreactivity and...

  4. 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...

  5. Critical Endothelial Regulation by LRP5 during Retinal Vascular Development

    Science.gov (United States)

    Huang, Wei; Li, Qing; Amiry-Moghaddam, Mahmood; Hokama, Madoka; Sardi, Sylvia H.; Nagao, Masashi; Warman, Matthew L.; Olsen, Bjorn R.

    2016-01-01

    Vascular abnormalities in the eye are the leading cause of many forms of inherited and acquired human blindness. Loss-of-function mutations in the Wnt-binding co-receptor LRP5 leads to aberrant ocular vascularization and loss of vision in genetic disorders such as osteoporosis-pseudoglioma syndrome. The canonical Wnt-β-catenin pathway is known to regulate retinal vascular development. However, it is unclear what precise role LPR5 plays in this process. Here, we show that loss of LRP5 function in mice causes retinal hypovascularization during development as well as retinal neovascularization in adulthood with disorganized and leaky vessels. Using a highly specific Flk1-CreBreier line for vascular endothelial cells, together with several genetic models, we demonstrate that loss of endothelium-derived LRP5 recapitulates the retinal vascular defects in Lrp5-/- mice. In addition, restoring LRP5 function only in endothelial cells in Lrp5-/- mice rescues their retinal vascular abnormalities. Furthermore, we show that retinal vascularization is regulated by LRP5 in a dosage dependent manner and does not depend on LRP6. Our study provides the first direct evidence that endothelium-derived LRP5 is both necessary and sufficient to mediate its critical role in the development and maintenance of retinal vasculature. PMID:27031698

  6. 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

    . 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......Purpose: To describe the association between retinal vascular calibres and cardiovascular risk factors. Methods: Population-based cross-sectional study including 6353 participants of the TromsO Eye Study in Norway aged 38-87years. Retinal arteriolar calibre (central retinal artery equivalent) 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...

  7. 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.

  8. The Feasibility of Central Retinal Artery Doppler Ultrasonography in Patients with Sudden Visual Disturbance that's Caused by Retinal Vascular Occlusion

    International Nuclear Information System (INIS)

    We evaluated the usefulness of central retinal artery Doppler ultrasonography for assessing the patients with sudden visual disturbance that's caused by retinal vascular occlusion. The blood flow velocity and the resistive and pulsatile indexes were measured at the central retinal arteries of 65 patients with sudden visual disturbance. For all the subjects, the patient's affected eye was compared with the non-affected eye. We investigated the efficacy of the Doppler ultrasonography parameters to predict a significant visual loss on the Snellen test (<20/400). A significantly lower central retinal arterial flow velocity was measured in the affected eye as compared with the unaffected normal eye for all the subjects (p < 0.05). The ROC curves showed that the mean velocity was the best parameter to predict significant visual loss (p < 0.05). If a mean velocity of 4.3 cm/sec was chosen as the cutoff value to predict significant visual loss, then the sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 89%, 95%, 95%, 88% and 92%, respectively (estimated area = 0.958, p-value <0.01). Central retinal artery Doppler ultrasonography was helpful for predicting significant visual loss in patients who complain of sudden visual disturbance. In addition to the other ophthalmologic diagnostic modalities, Doppler ultrasonography may be a feasible modality to depict impending further visual loss of an ischemic origin

  9. 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.A. Ikram (Arfan); 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

  10. Effect of ocular shape and vascular geometry on retinal hemodynamics: a computational model.

    Science.gov (United States)

    Dziubek, Andrea; Guidoboni, Giovanna; Harris, Alon; Hirani, Anil N; Rusjan, Edmond; Thistleton, William

    2016-08-01

    A computational model for retinal hemodynamics accounting for ocular curvature is presented. The model combines (i) a hierarchical Darcy model for the flow through small arterioles, capillaries and small venules in the retinal tissue, where blood vessels of different size are comprised in different hierarchical levels of a porous medium; and (ii) a one-dimensional network model for the blood flow through retinal arterioles and venules of larger size. The non-planar ocular shape is included by (i) defining the hierarchical Darcy flow model on a two-dimensional curved surface embedded in the three-dimensional space; and (ii) mapping the simplified one-dimensional network model onto the curved surface. The model is solved numerically using a finite element method in which spatial domain and hierarchical levels are discretized separately. For the finite element method, we use an exterior calculus-based implementation which permits an easier treatment of non-planar domains. Numerical solutions are verified against suitably constructed analytical solutions. Numerical experiments are performed to investigate how retinal hemodynamics is influenced by the ocular shape (sphere, oblate spheroid, prolate spheroid and barrel are compared) and vascular architecture (four vascular arcs and a branching vascular tree are compared). The model predictions show that changes in ocular shape induce non-uniform alterations of blood pressure and velocity in the retina. In particular, we found that (i) the temporal region is affected the least by changes in ocular shape, and (ii) the barrel shape departs the most from the hemispherical reference geometry in terms of associated pressure and velocity distributions in the retinal microvasculature. These results support the clinical hypothesis that alterations in ocular shape, such as those occurring in myopic eyes, might be associated with pathological alterations in retinal hemodynamics. PMID:26445874

  11. 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

    PURPOSE: Retinal vascular fractal dimension, a measure of the density of the retinal vasculature, has been suggested as a marker of systemic microvascular disorders in diabetes. As hemoglobin concentration is tightly related to vascular physiology and hypoxia, the hypothesis was that hemoglobin...... 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...... 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...

  12. Therapeutic effect of apatinib-loaded nanoparticles on diabetes-induced retinal vascular leakage

    Science.gov (United States)

    Jeong, Ji Hoon; Nguyen, Hong Khanh; Lee, Jung Eun; Suh, Wonhee

    2016-01-01

    Apatinib, a novel and selective inhibitor of vascular endothelial growth factor (VEGF) receptor 2, has been demonstrated recently to exhibit anticancer efficacy by inhibiting the VEGF signaling pathway. Given the importance of VEGF in retinal vascular leakage, the present study was designed to investigate whether apatinib-loaded polymeric nanoparticles inhibit VEGF-mediated retinal vascular hyperpermeability and block diabetes-induced retinal vascular leakage. For the delivery of water-insoluble apatinib, the drug was encapsulated in nanoparticles composed of human serum albumin (HSA)-conjugated polyethylene glycol (PEG). In vitro paracellular permeability and transendothelial electric resistance assays showed that apatinib-loaded HSA-PEG (Apa-HSA-PEG) nanoparticles significantly inhibited VEGF-induced endothelial hyperpermeability in human retinal microvascular endothelial cells. In addition, they substantially reduced the VEGF-induced junctional loss and internalization of vascular endothelial-cadherin, a major component of endothelial junction complexes. In vivo intravitreal injection of Apa-HSA-PEG nanoparticles in mice blocked VEGF-induced retinal vascular leakage. These in vitro and in vivo data indicated that Apa-HSA-PEG nanoparticles efficiently blocked VEGF-induced breakdown of the blood–retinal barrier. In vivo experiments with streptozotocin-induced diabetic mice showed that an intravitreal injection of Apa-HSA-PEG nanoparticles substantially inhibited diabetes-induced retinal vascular leakage. These results demonstrated, for the first time, that apatinib-loaded nanoparticles may be a promising therapeutic agent for the prevention and treatment of diabetes-induced retinal vascular disorders. PMID:27462154

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

    OpenAIRE

    Rohina S Aggarwal; Mishra, Vineet V; Somesh V Aggarwal

    2013-01-01

    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 pred...

  14. A Method for Visualization of Fine Retinal Vascular Pulsation Using Nonmydriatic Fundus Camera Synchronized with Electrocardiogram

    OpenAIRE

    Dinesh Kant Kumar; Behzad Aliahmad; Hao Hao; Mohd Zulfaezal Che Azemin; Ryo Kawasaki

    2013-01-01

    Pulsatile changes in retinal vascular geometry over the cardiac cycle have clinical implication for diagnosis of ocular and systemic vascular diseases. In this study, we report a Vesselness Mapping of Retinal Image Sequence (VMRS) methodology to visualize the vessel pulsation and quantify the pulsatile motions in the cardiac cycle. Retinal images were recorded in an image sequence corresponding to 8 segments of the cardiac cycle using a nonmydriatic fundus camera (Canon CR45, Canon Inc., Japa...

  15. Clinical pathology and retinal vascular structure in the Bardet-Biedl syndrome.

    OpenAIRE

    Bek, T; Rosenberg, T

    1995-01-01

    A comparative study of clinical pathology and retinal vascular structure is described as studied by vascular casting in an eye of a patient with the Bardet-Biedl syndrome. At the time of examination the eye had been almost blind for at least 4 years. The histopathological examination showed a largely uniform loss of the outer retinal layers. The gross pathological examination of the cast ocular fundus showed three distinct zones, an inner zone inside the temporal vascular arcades where retina...

  16. Anti vascular endothelial growth factor (bevacizumab) in central retinal vein occlusion: an interventional case series

    International Nuclear Information System (INIS)

    Vascular endothelial growth factor plays major role in ocular angio genesis and retinal edema production and is a step forward in the management of ocular neovascularization and retinal edematous pathologies. To determine the efficacy and safety of intra-vitreal Avastin (Bevacizumab) in cases having central retinal vein occlusion. All patients with central retinal occlusion occurring in the past 3 months and seen between the study period were included in the study. Diagnosis of central retinal vein occlusion was made clinically by slit lamp biomicroscopy with 78D examination Patients who had received any treatment for and eyes which already had developed Anterior Segment Neovascularization, Neovascularization elsewhere or Neovascularization on disc at presentation were excluded. Dose of 0.05 ml (1.25mg) of Avastin (Bevacizumab) was used as intra vitreal injection every month for 3 months in cases that presented within a month of occlusion and less injections were given in dose presenting later. Follow-up was done at 30th, 60th, 90th and 120th day after the onset of disease. Visual outcome was defined as Snellen's or LogMar Best Corrected Visual Acuity at final follow up, of 120th day, compared to the visual acuity at presentation. Data were analyzed by SPSS version 17. Total of 17 eyes of 17 patients were included in this study. Eleven (64.7%) patients were males while 6(35.3%) were females. Total of 40 intra-vitreal injections of Avastin were given to patients with a mean of 2.35 injections per eye. Good visual outcome was achieved in 10(58.8%) eyes, while 7(41.2%) had stable visual outcome. Mean initial Best Corrected Visual Acuity (LogMar) in all 17 eyes was 1.79(SD+0.87) which significantly improved to a mean of 1.18 (SD+0.77) at final follow up. Mean improvement in Best Corrected Visual Acuity (LogMar) after paired sample test in all patients at final follow up on day 120 was 0.61(SD+0.84). Retinal hemorrhages and macular edema decreased clinically on

  17. Quantitative Proteomics Reveals β2 Integrin-mediated Cytoskeletal Rearrangement in Vascular Endothelial Growth Factor (VEGF)-induced Retinal Vascular Hyperpermeability.

    Science.gov (United States)

    Jo, Dong Hyun; Bae, Jingi; Chae, Sehyun; Kim, Jin Hyoung; Han, Jong-Hee; Hwang, Daehee; Lee, Sang-Won; Kim, Jeong Hun

    2016-05-01

    Retinal vascular hyperpermeability causes macular edema, leading to visual deterioration in retinal diseases such as diabetic retinopathy and retinal vascular occlusion. Dysregulation of junction integrity between endothelial cells by vascular endothelial growth factor (VEGF) was shown to cause retinal vascular hyperpermeability. Accordingly, anti-VEGF agents have been used to treat retinal vascular hyperpermeability. However, they can confer potential toxicity through their deleterious effects on maintenance and survival of neuronal and endothelial cells in the retina. Thus, it is important to identify novel therapeutic targets for retinal vascular hyperpermeability other than VEGF. Here, we prepared murine retinas showing VEGF-induced vascular leakage from superficial retinal vascular plexus and prevention of VEGF-induced leakage by anti-VEGF antibody treatment. We then performed comprehensive proteome profiling of these samples and identified retinal proteins for which abundances were differentially expressed by VEGF, but such alterations were inhibited by anti-VEGF antibody. Functional enrichment and network analyses of these proteins revealed the β2 integrin pathway, which can prevent dysregulation of junction integrity between endothelial cells through cytoskeletal rearrangement, as a potential therapeutic target for retinal vascular hyperpermeability. Finally, we experimentally demonstrated that inhibition of the β2 integrin pathway salvaged VEGF-induced retinal vascular hyperpermeability, supporting its validity as an alternative therapeutic target to anti-VEGF agents. PMID:26969716

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

    Directory of Open Access Journals (Sweden)

    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

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

    Directory of Open Access Journals (Sweden)

    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.

  20. Relationship between retinal vascular occlusions and incident cerebrovascular diseases: A systematic review and meta-analysis.

    Science.gov (United States)

    Zhou, Yue; Zhu, Wengen; Wang, Changyun

    2016-06-01

    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

  1. 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.

  2. Retinal vascular imaging in early life: insights into processes and risk of cardiovascular disease.

    Science.gov (United States)

    Li, Ling-Jun; Ikram, Mohammad Kamran; Wong, Tien Yin

    2016-04-15

    Cardiovascular disease (CVD) is the leading cause of morbidity and mortality globally. In recent years, studies have shown that the origins of CVD may be traced to vascular and metabolic processes in early life. Retinal vascular imaging is a new technology that allows detailed non-invasive in vivo assessment and monitoring of the microvasculature. In this systematic review, we described the application of retinal vascular imaging in children and adolescents, and we examined the use of retinal vascular imaging in understanding CVD risk in early life. We reviewed all publications with quantitative retinal vascular assessment in two databases: PubMed and Scopus. Early life CVD risk factors were classified into four groups: birth risk factors, environmental risk factors, systemic risk factors and conditions linked to future CVD development. Retinal vascular changes were associated with lower birth weight, shorter gestational age, low-fibre and high-sugar diet, lesser physical activity, parental hypertension history, childhood hypertension, childhood overweight/obesity, childhood depression/anxiety and childhood type 1 diabetes mellitus. In summary, there is increasing evidence supporting the view that structural changes in the retinal microvasculature are associated with CVD risk factors in early life. Thus, the retina is a useful site for pre-clinical assessment of microvascular processes that may underlie the future development of CVD in adulthood. PMID:26435039

  3. 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.

  4. 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.

  5. A rare and unusual retinal arterioarterial communication in a prepapillary vascular loop

    OpenAIRE

    Makino, Shinji

    2014-01-01

    Fundus examination of a 40-year-old man presenting with blurred vision in his right eye revealed mild vitreous hemorrhage, a prepapillary vascular loop, and a peripapillary epiretinal membrane. Additionally, a superotemporal branch retinal artery communicated directly with an inferotemporal branch retinal artery in the temporal fovea at 2 locations. Fluorescein angiography confirmed an extremely rare arterioarterial communication. Two weeks later the vitreous hemorrhage and small intraretinal...

  6. Changes in the foveal microstructure after intravitreal bevacizumab application in patients with retinal vascular disease

    OpenAIRE

    Feucht, Nikolaus

    2013-01-01

    Nikolaus Feucht, Etienne Michael Schönbach, Ines Lanzl, Konstantin Kotliar, Chris Patrick Lohmann, Mathias MaierDepartment of Ophthalmology, Technical University of Munich, Munich, GermanyPurpose: To investigate changes in the area of the foveal avascular zone (FAZ) in patients with retinal vascular disease.Patients and methods: This retrospective, consecutive study examined 53 eyes of 53 patients with macular edema due to branch retinal vein occlusion in 25 patients (47.2%) and nonp...

  7. 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.

  8. The unfolded protein response in retinal vascular diseases: implications and therapeutic potential beyond protein folding.

    Science.gov (United States)

    Zhang, Sarah X; Ma, Jacey H; Bhatta, Maulasri; Fliesler, Steven J; Wang, Joshua J

    2015-03-01

    Angiogenesis is a complex, step-wise process of new vessel formation that is involved in both normal embryonic development as well as postnatal pathological processes, such as cancer, cardiovascular disease, and diabetes. Aberrant blood vessel growth, also known as neovascularization, in the retina and the choroid is a major cause of vision loss in severe eye diseases, such as diabetic retinopathy, age-related macular degeneration, retinopathy of prematurity, and central and branch retinal vein occlusion. Yet, retinal neovascularization is causally and dynamically associated with vasodegeneration, ischemia, and vascular remodeling in retinal tissues. Understanding the mechanisms of retinal neovascularization is an urgent unmet need for developing new treatments for these devastating diseases. Accumulating evidence suggests a vital role for the unfolded protein response (UPR) in regulation of angiogenesis, in part through coordinating the secretion of pro-angiogenic growth factors, such as VEGF, and modulating endothelial cell survival and activity. Herein, we summarize current research in the context of endoplasmic reticulum (ER) stress and UPR signaling in retinal angiogenesis and vascular remodeling, highlighting potential implications of targeting these stress response pathways in the prevention and treatment of retinal vascular diseases that result in visual deficits and blindness. PMID:25529848

  9. Association of reduced Connexin 43 expression with retinal vascular lesions in human diabetic retinopathy.

    Science.gov (United States)

    Tien, Thomas; Muto, Tetsuya; Zhang, Joyce; Sohn, Elliott H; Mullins, Robert F; Roy, Sayon

    2016-05-01

    Connexin 43 (Cx43) downregulation promotes apoptosis in retinal vascular cells of diabetic animal models; however, its relevance to human diabetic retinopathy has not been established. In this study, we investigated whether diabetes alters Cx43 expression and promotes retinal vascular lesions in human retinas. Diabetic human eyes (aged 64-94 years) and non-diabetic human eyes (aged 61-90 years) were analyzed in this study. Retinal protein samples and retinal capillary networks were assessed for Cx43 level by Western blot (WB) analysis and immunostaining. In parallel, retinal capillary networks were stained with hematoxylin and periodic acid Schiff to determine the extent of pericyte loss (PL) and acellular capillaries (AC) in these retinas. Cx43 protein expression was significantly reduced in the diabetic retinas compared to non-diabetic retinas as indicated by WB analysis (81 ± 11% of control). Additionally, a significant decrease in the number of Cx43 plaques per unit length of vessel was observed in the diabetic retinas compared to those of non-diabetic retinas (62 ± 10% of control; p diabetic retinas and Cx43 reduction is associated with increased vascular cell death. These findings suggest that diabetes decreases retinal Cx43 expression and that the development of PL and AC is associated with reduced Cx43 expression in human diabetic retinopathy. PMID:26738943

  10. Minocycline prevents retinal inflammation and vascular permeability following ischemia-reperfusion injury

    Science.gov (United States)

    2013-01-01

    Background Many retinal diseases are associated with vascular dysfunction accompanied by neuroinflammation. We examined the ability of minocycline (Mino), a tetracycline derivative with anti-inflammatory and neuroprotective properties, to prevent vascular permeability and inflammation following retinal ischemia-reperfusion (IR) injury, a model of retinal neurodegeneration with breakdown of the blood-retinal barrier (BRB). Methods Male Sprague–Dawley rats were subjected to 45 min of pressure-induced retinal ischemia, with the contralateral eye serving as control. Rats were treated with Mino prior to and following IR. At 48 h after reperfusion, retinal gene expression, cellular inflammation, Evan’s blue dye leakage, tight junction protein organization, caspase-3 activation, and DNA fragmentation were measured. Cellular inflammation was quantified by flow-cytometric evaluation of retinal tissue using the myeloid marker CD11b and leukocyte common antigen CD45 to differentiate and quantify CD11b+/CD45low microglia, CD11b+/CD45hi myeloid leukocytes and CD11bneg/CD45hi lymphocytes. Major histocompatibility complex class II (MHCII) immunoreactivity was used to determine the inflammatory state of these cells. Results Mino treatment significantly inhibited IR-induced retinal vascular permeability and disruption of tight junction organization. Retinal IR injury significantly altered mRNA expression for 21 of 25 inflammation- and gliosis-related genes examined. Of these, Mino treatment effectively attenuated IR-induced expression of lipocalin 2 (LCN2), serpin peptidase inhibitor clade A member 3 N (SERPINA3N), TNF receptor superfamily member 12A (TNFRSF12A), monocyte chemoattractant-1 (MCP-1, CCL2) and intercellular adhesion molecule-1 (ICAM-1). A marked increase in leukostasis of both myeloid leukocytes and lymphocytes was observed following IR. Mino treatment significantly reduced retinal leukocyte numbers following IR and was particularly effective in decreasing the

  11. 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

  12. Arginase 2 deficiency prevents oxidative stress and limits hyperoxia-induced retinal vascular degeneration.

    Directory of Open Access Journals (Sweden)

    Jutamas Suwanpradid

    Full Text Available BACKGROUND: Hyperoxia exposure of premature infants causes obliteration of the immature retinal microvessels, leading to a condition of proliferative vitreoretinal neovascularization termed retinopathy of prematurity (ROP. Previous work has demonstrated that the hyperoxia-induced vascular injury is mediated by dysfunction of endothelial nitric oxide synthase resulting in peroxynitrite formation. This study was undertaken to determine the involvement of the ureahydrolase enzyme arginase in this pathology. METHODS AND FINDINGS: Studies were performed using hyperoxia-treated bovine retinal endothelial cells (BRE and mice with oxygen-induced retinopathy (OIR as experimental models of ROP. Treatment with the specific arginase inhibitor 2(S-amino-6-boronohexanoic acid (ABH prevented hyperoxia-induced apoptosis of BRE cells and reduced vaso-obliteration in the OIR model. Furthermore, deletion of the arginase 2 gene protected against hyperoxia-induced vaso-obliteration, enhanced physiological vascular repair, and reduced retinal neovascularization in the OIR model. Additional deletion of one copy of arginase 1 did not improve the vascular pathology. Analyses of peroxynitrite by quantitation of its biomarker nitrotyrosine, superoxide by dihydroethidium imaging and NO formation by diaminofluoroscein imaging showed that the protective actions of arginase 2 deletion were associated with blockade of superoxide and peroxynitrite formation and normalization of NOS activity. CONCLUSIONS: Our data demonstrate the involvement of arginase activity and arginase 2 expression in hyperoxia-induced vascular injury. Arginase 2 deletion prevents hyperoxia-induced retinal vascular injury by preventing NOS uncoupling resulting in decreased reactive oxygen species formation and increased nitric oxide bioavailability.

  13. Differential Diagnosis of Retinal Vasculitis

    Science.gov (United States)

    Abu El-Asrar, Ahmed M.; Herbort, Carl P.; Tabbara, Khalid F.

    2009-01-01

    Retinal vaculitis is a sight-threatening inflammatory eye condition that involves the retinal vessels. Detection of retinal vasculitis is made clinically, and confirmed with the help of fundus fluorescein angiography. Active vascular disease is characterized by exudates around retinal vessels resulting in white sheathing or cuffing of the affected vessels. In this review, a practical approach to the diagnosis of retinal vasculitis is discussed based on ophthalmoscopic and fundus fluorescein angiographic findings. PMID:20404987

  14. Differential Diagnosis of Retinal Vasculitis

    OpenAIRE

    Abu El-Asrar Ahmed; Herbort Carl; Tabbara Khalid

    2009-01-01

    Retinal vaculitis is a sight-threatening inflammatory eye condition that involves the retinal vessels. Detection of retinal vasculitis is made clinically, and confirmed with the help of fundus fluorescein angiography. Active vascular disease is characterized by exudates around retinal vessels resulting in white sheathing or cuffing of the affected vessels. In this review, a practical approach to the diagnosis of retinal vasculitis is discussed based on ophthalmoscopic and fundus fluorescein a...

  15. Differential diagnosis of retinal vasculitis

    Directory of Open Access Journals (Sweden)

    Abu El-Asrar Ahmed

    2009-01-01

    Full Text Available Retinal vaculitis is a sight-threatening inflammatory eye condition that involves the retinal vessels. Detection of retinal vasculitis is made clinically, and confirmed with the help of fundus fluorescein angiography. Active vascular disease is characterized by exudates around retinal vessels resulting in white sheathing or cuffing of the affected vessels. In this review, a practical approach to the diagnosis of retinal vasculitis is discussed based on ophthalmoscopic and fundus fluorescein angiographic findings.

  16. PARP1 gene knock-out increases resistance to retinal degeneration without affecting retinal function.

    Directory of Open Access Journals (Sweden)

    Ayse Sahaboglu

    Full Text Available Retinitis pigmentosa (RP is a group of inherited neurodegenerative diseases affecting photoreceptors and causing blindness in humans. Previously, excessive activation of enzymes belonging to the poly-ADP-ribose polymerase (PARP group was shown to be involved in photoreceptor degeneration in the human homologous rd1 mouse model for RP. Since there are at least 16 different PARP isoforms, we investigated the exact relevance of the predominant isoform - PARP1 - for photoreceptor cell death using PARP1 knock-out (KO mice. In vivo and ex vivo morphological analysis using optic coherence tomography (OCT and conventional histology revealed no major alterations of retinal phenotype when compared to wild-type (wt. Likewise, retinal function as assessed by electroretinography (ERG was normal in PARP1 KO animals. We then used retinal explant cultures derived from wt, rd1, and PARP1 KO animals to test their susceptibility to chemically induced photoreceptor degeneration. Since photoreceptor degeneration in the rd1 retina is triggered by a loss-of-function in phosphodiesterase-6 (PDE6, we used selective PDE6 inhibition to emulate the rd1 situation on non-rd1 genotypes. While wt retina subjected to PDE6 inhibition showed massive photoreceptor degeneration comparable to rd1 retina, in the PARP1 KO situation, cell death was robustly reduced. Together, these findings demonstrate that PARP1 activity is in principle dispensable for normal retinal function, but is of major importance for photoreceptor degeneration under pathological conditions. Moreover, our results suggest that PARP dependent cell death or PARthanatos may play a major role in retinal degeneration and highlight the possibility to use specific PARP inhibitors for the treatment of RP.

  17. INTRAOCULAR AND SERUM LEVELS OF VASCULAR ENDOTHELIAL GROWTH FACTOR IN ACUTE RETINAL NECROSIS AND OCULAR TOXOPLASMOSIS

    NARCIS (Netherlands)

    Wiertz, Karin; De Visser, Lenneke; Rijkers, Ger; De Groot-Mijnes, Jolanda; Los, Leonie; Rothova, Aniki

    2010-01-01

    Purpose: To determine the intraocular and serum vascular endothelial growth factor (VEGF) levels in patients with acute retinal necrosis (ARN) and compare those with VEGF levels found in patients with ocular toxoplasmosis (OT). Methods: Paired intraocular fluid and serum samples of 17 patients with

  18. Automatic detection of vascular bifurcations in segmented retinal images using trainable COSFIRE filters

    NARCIS (Netherlands)

    Azzopardi, George; Petkov, Nicolai

    2013-01-01

    Background: The vascular tree observed in a retinal fundus image can provide clues for cardiovascular diseases. Its analysis requires the identification of vessel bifurcations and crossovers. Methods: We use a set of trainable keypoint detectors that we call Combination Of Shifted Filter REsponses o

  19. 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.

  20. 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.

  1. 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

    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 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...

  2. Accelerated ischemic vascular retinopathy after intravitreally injected bevacizumab for central retinal vein occlusion in elderly patients

    Directory of Open Access Journals (Sweden)

    Isola V

    2013-03-01

    Full Text Available Vincenzo Isola,1 Alfredo Pece,1,2 Claudio Massironi,1 Simone Reposi,1 Fabio Dimastrogiovanni11Department of Ophthalmology, Melegnano Hospital, 2Fondazione Retina 3000, Milano, ItalyBackground: Ischemic changes in the retinal circulation are an uncommon but severe adverse vascular reaction to intravitreal bevacizumab (Avastin®, Genentech, San Francisco, CA, USA/Roche, Basel, Switzerland for central retinal vein occlusion (CRVO. In the two cases reported here, ischemic changes in the retina vasculature following intravitreal bevacizumab for CRVO were observed with the aim of describing the clinical and angiographic features of these changes.Methods: Two elderly patients with recent-onset CRVO received one off-label intravitreal injection of bevacizumab 0.05 mL/1.25 mg.Results: In Case 1, the patient's pre-treatment visual acuity was 20/400. At 3 weeks post injection, the patient could count fingers at a distance of 1 ft (30 cm and fluorescein angiography showed reduction in intraretinal hemorrhages and areas of retinal non-perfusion. However, at 6 weeks these were markedly increased compared with those seen in the photograph taken 3 weeks after treatment. In Case 2, the patient's pre-treatment visual acuity was 20/200. At 1 month post injection, vision had decreased to 20/400 and fluorescein angiography showed severe macular ischemia with a remarkable capillary dropout throughout the macula.Conclusion: Ischemic retinal injury may be an uncommon but severe adverse vascular reaction to intravitreal bevacizumab for CRVO. Although progression of retinal ischemia in CRVO could be observed shortly after intravitreal bevacizumab, whether this is a drug- or procedure-related effect or part of the natural history of the condition remains uncertain.Keywords: Avastin, ischemia, macular infarction, intraretinal hemorrhage, retinal non-perfusion

  3. Estimating retinal vascular permeability using the adiabatic approximation to the tissue homogeneity model with fluorescein videoangiography

    Science.gov (United States)

    Tichauer, Kenneth M.; Osswald, Christian R.; Dosmar, Emily; Guthrie, Micah J.; Hones, Logan; Sinha, Lagnojita; Xu, Xiaochun; Mieler, William F.; St. Lawrence, Keith; Kang-Mieler, Jennifer J.

    2015-06-01

    Clinical symptoms of diabetic retinopathy are not detectable until damage to the retina reaches an irreversible stage, at least by today's treatment standards. As a result, there is a push to develop new, "sub-clinical" methods of predicting the onset of diabetic retinopathy before the onset of irreversible damage. With diabetic retinopathy being associated with the accumulation of long-term mild damage to the retinal vasculature, retinal blood vessel permeability has been proposed as a key parameter for detecting preclinical stages of retinopathy. In this study, a kinetic modeling approach used to quantify vascular permeability in dynamic contrast-enhanced medical imaging was evaluated in noise simulations and then applied to retinal videoangiography data in a diabetic rat for the first time to determine the potential for this approach to be employed clinically as an early indicator of diabetic retinopathy. Experimental levels of noise were found to introduce errors of less than 15% in estimates of blood flow and extraction fraction (a marker of vascular permeability), and fitting of rat retinal fluorescein angiography data provided stable maps of both parameters.

  4. Arginase 2 Deficiency Prevents Oxidative Stress and Limits Hyperoxia-Induced Retinal Vascular Degeneration

    OpenAIRE

    Suwanpradid, Jutamas; Rojas, Modesto; Behzadian, M. Ali; Caldwell, R. William; Caldwell, Ruth B.

    2014-01-01

    Background Hyperoxia exposure of premature infants causes obliteration of the immature retinal microvessels, leading to a condition of proliferative vitreoretinal neovascularization termed retinopathy of prematurity (ROP). Previous work has demonstrated that the hyperoxia-induced vascular injury is mediated by dysfunction of endothelial nitric oxide synthase resulting in peroxynitrite formation. This study was undertaken to determine the involvement of the ureahydrolase enzyme arginase in thi...

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

    OpenAIRE

    Emarah, Ahmed

    2010-01-01

    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 cavern...

  6. βA3/A1-crystallin in astroglial cells regulates retinal vascular remodeling during development

    Science.gov (United States)

    Sinha, Debasish; Klise, Andrew; Sergeev, Yuri; Hose, Stacey; Bhutto, Imran A.; Hackler, Laszlo; Malpic-llanos, Tanya; Samtani, Sonia; Grebe, Rhonda; Goldberg, Morton F.; Hejtmancik, J. Fielding; Nath, Avindra; Zack, Donald J.; Fariss, Robert N.; McLeod, D. Scott; Sundin, Olof; Broman, Karl W.; Lutty, Gerard A.; Zigler, J. Samuel

    2016-01-01

    Vascular remodeling is a complex process critical to development of the mature vascular system. Astrocytes are known to be indispensable for initial formation of the retinal vasculature; our studies with the Nuc1 rat provide novel evidence that these cells are also essential in the retinal vascular remodeling process. Nuc1 is a spontaneous mutation in the Sprague–Dawley rat originally characterized by nuclear cataracts in the heterozygote and microphthalmia in the homozygote. We report here that the Nuc1 allele results from mutation of the βA3/A1-crystallin gene, which in the neural retina is expressed only in astrocytes. We demonstrate striking structural abnormalities in Nuc1 astrocytes with profound effects on the organization of intermediate filaments. While vessels form in the Nuc1 retina, the subsequent remodeling process required to provide a mature vascular network is deficient. Our data implicate βA3/A1-crystallin as an important regulatory factor mediating vascular patterning and remodeling in the retina. PMID:17931883

  7. Retinal Vascular Endothelial Growth Factor Induces Intercellular Adhesion Molecule-1 and Endothelial Nitric Oxide Synthase Expression and Initiates Early Diabetic Retinal Leukocyte Adhesion in Vivo

    OpenAIRE

    Joussen, Antonia M; Poulaki, Vassiliki; Qin, Wenying; Kirchhof, Bernd; Mitsiades, Nicholas; Wiegand, Stanley J; Rudge, John; George D. Yancopoulos; Adamis, Anthony P.

    2002-01-01

    Leukocyte adhesion to the diabetic retinal vasculature results in early blood-retinal barrier breakdown, capillary nonperfusion, and endothelial cell injury and death. Previous work has shown that intercellular adhesion molecule-1 (ICAM-1) and CD18 are required for these processes. However the relevant in vivo stimuli for ICAM-1 and CD18 expression in diabetes remain unknown. The current study investigated the causal role of endogenous vascular endothelial growth factor (VEGF) and nitric oxid...

  8. Comprehensive automatic assessment of retinal vascular abnormalities for computer-assisted retinopathy grading.

    Science.gov (United States)

    Joshi, Vinayak; Agurto, Carla; VanNess, Richard; Nemeth, Sheila; Soliz, Peter; Barriga, Simon

    2014-01-01

    One of the most important signs of systemic disease that presents on the retina is vascular abnormalities such as in hypertensive retinopathy. Manual analysis of fundus images by human readers is qualitative and lacks in accuracy, consistency and repeatability. Present semi-automatic methods for vascular evaluation are reported to increase accuracy and reduce reader variability, but require extensive reader interaction; thus limiting the software-aided efficiency. Automation thus holds a twofold promise. First, decrease variability while increasing accuracy, and second, increasing the efficiency. In this paper we propose fully automated software as a second reader system for comprehensive assessment of retinal vasculature; which aids the readers in the quantitative characterization of vessel abnormalities in fundus images. This system provides the reader with objective measures of vascular morphology such as tortuosity, branching angles, as well as highlights of areas with abnormalities such as artery-venous nicking, copper and silver wiring, and retinal emboli; in order for the reader to make a final screening decision. To test the efficacy of our system, we evaluated the change in performance of a newly certified retinal reader when grading a set of 40 color fundus images with and without the assistance of the software. The results demonstrated an improvement in reader's performance with the software assistance, in terms of accuracy of detection of vessel abnormalities, determination of retinopathy, and reading time. This system enables the reader in making computer-assisted vasculature assessment with high accuracy and consistency, at a reduced reading time. PMID:25571442

  9. Retinal vascular fractal dimension, childhood IQ, and cognitive ability in old age: the Lothian Birth Cohort Study 1936.

    Directory of Open Access Journals (Sweden)

    Adele M Taylor

    Full Text Available Cerebral microvascular disease is associated with dementia. Differences in the topography of the retinal vascular network may be a marker for cerebrovascular disease. The association between cerebral microvascular state and non-pathological cognitive ageing is less clear, particularly because studies are rarely able to adjust for pre-morbid cognitive ability level. We measured retinal vascular fractal dimension (Df as a potential marker of cerebral microvascular disease. We examined the extent to which it contributes to differences in non-pathological cognitive ability in old age, after adjusting for childhood mental ability.Participants from the Lothian Birth Cohort 1936 Study (LBC1936 had cognitive ability assessments and retinal photographs taken of both eyes aged around 73 years (n = 648. IQ scores were available from childhood. Retinal vascular Df was calculated with monofractal and multifractal analysis, performed on custom-written software. Multiple regression models were applied to determine associations between retinal vascular Df and general cognitive ability (g, processing speed, and memory.Only three out of 24 comparisons (two eyes × four Df parameters × three cognitive measures were found to be significant. This is little more than would be expected by chance. No single association was verified by an equivalent association in the contralateral eye.The results show little evidence that fractal measures of retinal vascular differences are associated with non-pathological cognitive ageing.

  10. Changes in the foveal microstructure after intravitreal bevacizumab application in patients with retinal vascular disease

    Directory of Open Access Journals (Sweden)

    Feucht N

    2013-01-01

    Full Text Available Nikolaus Feucht, Etienne Michael Schönbach, Ines Lanzl, Konstantin Kotliar, Chris Patrick Lohmann, Mathias MaierDepartment of Ophthalmology, Technical University of Munich, Munich, GermanyPurpose: To investigate changes in the area of the foveal avascular zone (FAZ in patients with retinal vascular disease.Patients and methods: This retrospective, consecutive study examined 53 eyes of 53 patients with macular edema due to branch retinal vein occlusion in 25 patients (47.2% and nonproliferative diabetic retinopathy in 28 patients (52.8%. The macular edema was treated with an intravitreal injection of 0.05 mL equal to 1.25 mg bevacizumab. Before and 6–8 weeks after the injection, best corrected visual acuity, slit lamp biomicroscopy of the anterior segment and fundus, optical coherence tomography, and fluorescein angiography were conducted. The FAZ was manually circumscribed on early-phase angiography images and the area of the FAZ was measured.Results: The preoperative overall mean FAZ area was 0.327 ± 0.126 mm2 (median 0.310 mm2. At the control consultation, the overall mean area was significantly larger (0.422 ± 0.259 mm2; median 0.380 mm2; P < 0.001. In the nonproliferative diabetic retinopathy subpopulation, the mean area was 0.361 ± 0.129 mm2 (median 0.330 mm2 before bevacizumab application and 0.434 mm2 at the follow-up visit (mean increase 0.071 mm2/19.7%. In the branch retinal vein occlusion group, the baseline FAZ area was 0.290 ± 0.115 mm2 and 0.407 ± 0.350 mm2 at follow-up (median 0.330 mm2; mean increase 0.117 mm2/40.3%. No cases of severe operation-associated complications were observed.Conclusion: The results confirm the safety of intravitreal bevacizumab injection in patients with macular edema due to nonproliferative diabetic retinopathy and branch retinal vein occlusion. The enlargement of the FAZ could be equivalent to an increase in retinal ischemia. These results may be transient; a potential vascular risk, however

  11. 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.

  12. 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.

  13. Retinal overexpression of angiopoietin-2 mimics diabetic retinopathy and enhances vascular damages in hyperglycemia.

    Science.gov (United States)

    Pfister, Frederick; Wang, Yumei; Schreiter, Kay; vom Hagen, Franziska; Altvater, Karin; Hoffmann, Sigrid; Deutsch, Urban; Hammes, Hans-Peter; Feng, Yuxi

    2010-03-01

    Our previous data suggested that angiopoietin-2 (Ang-2) is linked to pericyte loss, thereby playing an important role in diabetic retinopathy. In this study, we investigated the effect of retinal overexpression of human Ang-2 (mOpsinhAng2 mouse) on vascular morphology in non-diabetic and streptozotozin-induced diabetic animals. Pericyte (PC) coverage and acellular capillary (AC) formation were quantitated in retinal digest preparations after 3 and 6 months of diabetes duration. The degree of retinopathy in non-diabetic mOpsinhAng2 mice at 3 months (-21% PC, +49% AC) was comparable to age-matched diabetic wild type mice. Diabetic mOpsinhAng2 mice exhibited significantly worse vascular pathology than wild type counterparts at 6 months. Quantitative PCR revealed that human Ang-2 mRNA was highly overexpressed in retinas of transgenic mice. Our data demonstrate that overexpression of Ang-2 in the retina enhances vascular pathology, indicating that Ang-2 plays an essential role in diabetic vasoregression via destabilization of pericytes. PMID:19238311

  14. 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.

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

    International Nuclear Information System (INIS)

    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% O2). 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

  16. Zebrafish (Danio rerio) embryo as a platform for the identification of novel angiogenesis inhibitors of retinal vascular diseases.

    Science.gov (United States)

    Rezzola, Sara; Paganini, Giuseppe; Semeraro, Francesco; Presta, Marco; Tobia, Chiara

    2016-07-01

    Pathological angiogenesis of the retina is a main cause of blindness. Therapeutic approaches targeting vascular endothelial growth factor, a main angiogenesis inducer in retinal vascular diseases, show significant limitations. Thus, experimental models of retinal neovascularization remain crucial for investigating novel anti-angiogenic strategies and bringing them to patients. Recent observations have shown that eye neovascularization in zebrafish (Danio rerio) embryo may represent a novel target for the identification of angiogenesis inhibitors. This review highlights the use of zebrafish embryo as an innovative model system for the screening of anti-angiogenic molecules to be employed for the treatment of angiogenesis-dependent eye diseases. PMID:27085972

  17. MRP4 knockdown enhances migration, suppresses apoptosis, and produces aggregated morphology in human retinal vascular endothelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Tagami, Mizuki [Department of Surgery Related, Division of Ophthalmology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe 650-0017 (Japan); Kusuhara, Sentaro, E-mail: kusu@med.kobe-u.ac.jp [Department of Surgery Related, Division of Ophthalmology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe 650-0017 (Japan); Imai, Hisanori [Department of Surgery Related, Division of Ophthalmology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe 650-0017 (Japan); Uemura, Akiyoshi [Department of Surgery Related, Division of Ophthalmology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe 650-0017 (Japan); Department of Vascular Biology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe 650-0017 (Japan); Honda, Shigeru; Tsukahara, Yasutomo; Negi, Akira [Department of Surgery Related, Division of Ophthalmology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe 650-0017 (Japan)

    2010-10-01

    Research highlights: {yields} Exogenous VEGF decreases MRP4 expression in a dose-dependent manner. {yields} MRP4 knockdown leads to enhanced cell migration. {yields} MRP4 knockdown suppresses caspase-3-mediated cell apoptosis. {yields} MRP4 knockdown produces cell assembly and cell aggregation. -- Abstract: The multidrug resistance protein (MRP) MRP4/ABCC4 is an ATP-binding cassette transporter that actively effluxes endogenous and xenobiotic substrates out of cells. In the rodent retina, Mrp4 mRNA and protein are exclusively expressed in vascular endothelial cells, but the angiogenic properties of Mrp4 are poorly understood so far. This study aims to explore the angiogenic properties of MRP4 in human retinal microvascular endothelial cells (HRECs) utilizing the RNA interference (RNAi) technique. MRP4 expression was decreased at the mRNA and protein levels after stimulation with exogenous vascular endothelial growth factor in a dose-dependent manner. RNAi-mediated MRP4 knockdown in HRECs do not affect cell proliferation but enhances cell migration. Moreover, cell apoptosis induced by serum starvation was less prominent in MRP4 siRNA-treated HRECs as compared to control siRNA-treated HRECs. In a Matrigel-based tube-formation assay, although MRP4 knockdown did not lead to a significant change in the total tube length, MRP4 siRNA-treated HRECs assembled and aggregated into a massive tube-like structure, which was not observed in control siRNA-treated HRECs. These results suggest that MRP4 is uniquely involved in retinal angiogenesis.

  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 a...

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

    Science.gov (United States)

    Weinl, Christine; Wasylyk, Christine; Garcia Garrido, Marina; Sothilingam, Vithiyanjali; Beck, Susanne C; Riehle, Heidemarie; Stritt, Christine; Roux, Michel J; Seeliger, Mathias W; Wasylyk, Bohdan; Nordheim, Alfred

    2014-01-01

    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. PMID:25203538

  20. 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.

  1. Fatp1 deficiency affects retinal light response and dark adaptation, and induces age-related alterations.

    Directory of Open Access Journals (Sweden)

    Karim Chekroud

    Full Text Available FATP1 is involved in lipid transport into cells and in intracellular lipid metabolism. We showed previously that this protein interacts with and inhibits the limiting-step isomerase of the visual cycle RPE65. Here, we aimed to analyze the effect of Fatp1-deficiency in vivo on the visual cycle, structure and function, and on retinal aging. Among the Fatp family members, we observed that only Fatp1 and 4 are expressed in the control retina, in both the neuroretina and the retinal pigment epithelium. In the neuroretina, Fatp1 is mostly expressed in photoreceptors. In young adult Fatp1(-/- mice, Fatp4 expression was unchanged in retinal pigment epithelium and reduced two-fold in the neuroretina as compared to Fatp1(+/+ mice. The Fatp1(-/- mice had a preserved retinal structure but a decreased electroretinogram response to light. These mice also displayed a delayed recovery of the b-wave amplitude after bleaching, however, visual cycle speed was unchanged, and both retinal pigment epithelium and photoreceptors presented the same fatty acid pattern compared to controls. In 2 year-old Fatp1(-/- mice, transmission electron microscopy studies showed specific abnormalities in the retinas comprising choroid vascularization anomalies and thickening of the Bruch membrane with material deposits, and sometimes local disorganization of the photoreceptor outer segments. These anomalies lead us to speculate that the absence of FATP1 accelerates the aging process.

  2. The effect of voluntary fasting and dehydration on flicker-induced retinal vascular dilation in a healthy individual: a case report

    Directory of Open Access Journals (Sweden)

    Heitmar Rebekka

    2008-05-01

    Full Text Available Abstract Introduction Dynamic retinal vessel analysis represents a well-established method for the assessment of vascular reactivity during both normal conditions and after various provocations. We present a case where the subject showed abnormal retinal vessel reactivity after fasting voluntarily for 20 hours. Case presentation A healthy, 21-year-old man who fasted voluntarily for 20 hours exhibited abnormal retinal vascular reactivity (dilation and constriction after flicker provocation as measured using the Dynamic Retinal Vessel Analyser (Imedos, Jena, Germany. Conclusion The abnormal vascular reactivity induced by fasting was significant; abnormal levels of important nutrients due to fasting and dehydration could play a role through altering the concentration of vasoactive substances such as nitric oxide. This hypothesis needs further investigation.

  3. Freezing adversely affects measurement of vascular endothelial growth factor levels in human aqueous samples

    Directory of Open Access Journals (Sweden)

    Sankarathi Balaiya

    2011-01-01

    Full Text Available Sankarathi Balaiya Sandeep Grover Ravi K Murthy Kakarla V ChalamDepartment of Ophthalmology, University of Florida College of Medicine, Jacksonville, FL, USAPurpose: Aqueous levels of vascular endothelial growth factor (VEGF can be a surrogate marker of intraocular VEGF activity and a measure of efficacy of anti-VEGF treatment in a variety of vasoproliferative retinal disorders, including diabetic retinopathy, age-related macular degeneration, and central retinal vein occlusion. Measurement of the VEGF level may be adversely affected by premeasurement variables, such as freezing and delay, in sample analysis. We aim to evaluate the effect of storage and delayed measurement of human aqueous VEGF levels in these conditions.Methods: Aqueous samples collected from patients receiving intravitreal injection of bevacizumab for various retinal diseases were divided into two groups. In Group 1, the VEGF levels were analyzed on the same day; in Group 2, the VEGF levels were analyzed after 21 days of freezer storage (-80°C using immunobead assay. Statistical comparison using a paired t-test was performed between the two groups.Results: Thirty-one aqueous humor samples were collected, and the VEGF concentration for fresh samples was 7.8 ± 5.9 pg/mL (mean ± SD compared to 6.5 ± 6.0 pg/mL in frozen samples, resulting in a statistically significant difference (P = 0.03.Conclusions: Accurate measurement of the VEGF level is a vital component of clinical decision-making. Delayed analysis of VEGF levels in aqueous samples may result in significant sample degradation and lower levels of measured VEGF.Keywords: VEGF level, aqueous humor, immunobead assay, VEGF storage

  4. Other Retinal Diseases

    Science.gov (United States)

    ... Congenital Amaurosis Macular Degeneration Retinitis Pigmentosa Stargardt Disease Usher Syndrome Other Retinal Diseases Glossary News & Research News & ... affected by retinitis pigmentosa, age-related macular degeneration, Usher syndrome and the entire spectrum of retinal diseases. ...

  5. A CASE OF HELLP SYNDROME: THE IMPORTANCE OF ANGIOGRAPHY WITH INDOCIANINE GREEN FOR DIAGNOSIS OF RETINIC AND CHOROIDAL VASCULAR OCCLUSION.

    Directory of Open Access Journals (Sweden)

    R. Franceschini

    2012-05-01

    Full Text Available Purpose. To present a case of retinal and choroidal vascular occlusion in conjunction with HELLP syndrome. Methods. A 35 years-old woman presented with HELLP syndrome underwent cesarean delivery for preeclampsia. After 2 months she had a decrease of vision in OD. She had performed an eye examination with FAG and ICG. results. The FAG shows at the posterior pole in the perifoveola temporal area different areas of hyperfluorescence. ICG reveals frameworks of hypoperfusion in perimacular areas, for the probable presence of ischemic foci. After about 5 mounths she presented an improvement in visual acuity and a complete resolution of Ophtalmoscopic findings. Conclusions. Ophtalmic complications are possible during this syndrome. This is the first description of a patient suffering a retinal and choroidal vascolar occlusion after HELLP syndrome, and we report the important of ICG for\tdiagnosis\tof choroidal ischemia.

  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

    with a semiautomatic computer-based program (International Retinal Imaging Software; National University of Singapore, Republic of Singapore; University of Sydney, Sydney, and University of Melbourne, Melbourne, Australia). D(f) of the retinal vasculature was measured within a predefined circular region of 3.5 optic...... in any materials discussed in this article....

  7. 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. PMID:27017067

  8. Retinal vascular fractal dimension as a potential marker of treatment outcome in patients with proliferative diabetic retinopathy

    DEFF Research Database (Denmark)

    Torp, Thomas Lee; Vergmann, Anna Stage; Peto, Tunde;

    2016-01-01

    Design of study: Six months prospective, interventional clinical study. Purpose: The retinal vascular fractal dimension (FD) is a non-invasive marker of retinal vascular geometry. The purpose of the study was to evaluate FD as a preoperative biomarker for disease activity 6 month after panretinal...... of diabetes were 52±14 years and 21±11 years, respectively, and 75% were male. HbA1c was 68 ±16 mmol/mol, and the mean blood pressure was 183/84 mmHg. Groups 1 and 2 did not differ according to the mean number of laser spots (1581 vs. 1573, p=0.84) or the total laser energy delivered (13.67 joule vs...... (group 1, n=18) or stabilized (group 2, n=22) disease. FD was measured at baseline and month 6 by a trained grader using the Fractal Analyzer (Singapore Institute Vessel Assessment-Fractal image analysis software, Singapore) and a standardized grading-protocol. Results: At baseline, mean age and duration...

  9. Serial evaluation of retinal vascular changes in infants treated with intravitreal bevacizumab for aggressive posterior retinopathy of prematurity in zone I.

    Science.gov (United States)

    Padhi, T R; Das, T; Rath, S; Pradhan, L; Sutar, S; Panda, K G; Modi, R; Jalali, S

    2016-03-01

    PurposeTo evaluate the serial changes in retinal vasculature in infants treated with intravitreal bevacizumab (IVB) for aggressive posterior retinopathy of prematurity (APROP) in zone I.MethodsRetrospective analysis of serial changes in retinal vasculature after IVB in the seven eyes of four babies with APROP in zone I.ResultsThe initial regression, following IVB, was dramatic with reduction in vessel caliber and marked thinning and invisibility of the bridging shunts. Resurgent vascular development was very slow radially though there was continued abnormal vascular growth circumferentially. Common findings in all eyes were tangled vasculature and fine saw-toothed shunts. The variable findings were (1) new closely packed multilayered bridging shunts, long arching mature looking vessels, and finally a ridge at the periphery (n=3 eyes) at 52 weeks of postmenstrual age (PMA); (2) status quo at the stage of saw-toothed shunt and ridge in both eyes for a long time (n=2 eyes); and (3) multiple retinal hemorrhages within the vascularized retina and thick preretinal hemorrhage overlying the saw-toothed shunts and ridge that persisted for another 3 weeks and regressed 2 weeks after laser (n=1). The eyes that received bevacizumab alone (3) did not show any abnormal vascularization at 56 weeks of PMA or beyond.ConclusionsThe retinal vascularization following IVB was different than normal in terms of its time, speed, and morphology; few of these changes are first to be reported in the literature (Medline search) and warrants further studies. PMID:26584796

  10. Retinal vascular fractals predict long-term microvascular complications in type 1 diabetes mellitus

    DEFF Research Database (Denmark)

    Broe, Rebecca; Rasmussen, Malin L; Frydkjaer-Olsen, Ulrik;

    2014-01-01

    AIMS/HYPOTHESIS: Fractal analysis of the retinal vasculature provides a global measure of the complexity and density of retinal vessels summarised as a single variable: the fractal dimension. We investigated fractal dimensions as long-term predictors of microvasculopathy in type 1 diabetes. METHODS......: We included 180 patients with type 1 diabetes in a 16 year follow-up study. In baseline retinal photographs (from 1995), all vessels in a zone 0.5-2.0 disc diameters from the disc margin were traced using Singapore Institute Vessel Assessment-Fractal image analysis software. Artefacts were removed by...... a certified grader, and fractal dimensions were calculated using the box-counting method. At follow-up (in 2011), diabetic neuropathy, nephropathy and proliferative retinopathy were assessed and related to baseline fractal dimensions in multiple regressions adjusted for sex and baseline age...

  11. Retinal vasculature classification using novel multifractal features

    International Nuclear Information System (INIS)

    Retinal blood vessels have been implicated in a large number of diseases including diabetic retinopathy and cardiovascular diseases, which cause damages to retinal blood vessels. The availability of retinal vessel imaging provides an excellent opportunity for monitoring and diagnosis of retinal diseases, and automatic analysis of retinal vessels will help with the processes. However, state of the art vascular analysis methods such as counting the number of branches or measuring the curvature and diameter of individual vessels are unsuitable for the microvasculature. There has been published research using fractal analysis to calculate fractal dimensions of retinal blood vessels, but so far there has been no systematic research extracting discriminant features from retinal vessels for classifications. This paper introduces new methods for feature extraction from multifractal spectra of retinal vessels for classification. Two publicly available retinal vascular image databases are used for the experiments, and the proposed methods have produced accuracies of 85.5% and 77% for classification of healthy and diabetic retinal vasculatures. Experiments show that classification with multiple fractal features produces better rates compared with methods using a single fractal dimension value. In addition to this, experiments also show that classification accuracy can be affected by the accuracy of vessel segmentation algorithms. (paper)

  12. Retinal vein and artery occlusions

    DEFF Research Database (Denmark)

    Christiansen, Christine Benn; Lip, Gregory Y. H.; Lamberts, Morten;

    2013-01-01

    Retinal vascular occlusions may constitute an independent risk factor for stroke in patients with atrial fibrillation.......Retinal vascular occlusions may constitute an independent risk factor for stroke in patients with atrial fibrillation....

  13. The inhibition of advanced glycation end-products-induced retinal vascular permeability by silver nanoparticles.

    Science.gov (United States)

    Sheikpranbabu, Sardarpasha; Kalishwaralal, Kalimuthu; Lee, Kyung-Jin; Vaidyanathan, Ramanathan; Eom, Soo Hyun; Gurunathan, Sangiliyandi

    2010-03-01

    The increased permeability of the blood-retinal barrier is known to occur in patients with diabetes, and this defect contributes to retinal edema. This study aimed to determine the effects of silver nanoparticles (Ag-NPs) on advanced glycation end-products (AGEs)-induced endothelial cell permeability. Cultured porcine retinal endothelial cells (PRECs) were exposed to AGE-modified bovine serum albumin (AGE-BSA) and the endothelial cell permeability was detected by measuring the flux of RITC-dextran across the PREC monolayers. We found that AGE-BSA increased the dextran flux across a PREC monolayer and Ag-NPs blocked the solute flux induced by AGE-BSA. In order to understand the underlying signaling mechanism of Ag-NPs on the inhibitory effect of AGE-BSA-induced permeability, we demonstrated that Ag-NPs could inhibit the AGE-BSA-induced permeability via Src kinase pathway. AGE-BSA also increased the PREC permeability by stimulating the expression of intracellular adhesion molecule-1 (ICAM-1) and decreased the expression of occludin and ZO-1. Further, Ag-NPs inhibited the AGE-BSA-induced permeability by increased expression of tight junction proteins occludin and ZO-1, co-incident with an increase in barrier properties of endothelial monolayer. Together, our results indicate that Ag-NPs could possibly act as potent anti-permeability molecule by targeting the Src signaling pathway and tight junction proteins and it offers potential targets to inhibit the ocular related diseases. PMID:19963272

  14. PDMS content affects in vitro hemocompatibility of synthetic vascular grafts.

    Science.gov (United States)

    Spiller, Dario; Losi, Paola; Briganti, Enrica; Sbrana, Silverio; Kull, Silvia; Martinelli, Ilaria; Soldani, Giorgio

    2007-06-01

    An unsolved problem when employing small-diameter vascular grafts for aorto-coronary by-pass and peripheral reconstruction is the early thrombotic occlusion. The PEtU-PDMS is a new elastomeric material, composed of poly(ether)urethane and polydimethylsiloxane, synthesized to realize grafts with improved hemocompatibility characteristics. In order to investigate the effect of PDMS content on hemocompatibility, three different percentages of PDMS containing grafts (10, 25 and 40) were evaluated. Grafts realized with Estane 5714-F1 and silicone medical grade tubes were used as references. The hemocompatibility was investigated by an in vitro circuit in which human anticoagulated blood was circulated into grafts by a peristaltic pump modified to obtain a passive flow. For each experiment, 40 cm length graft was closed into a circular loop and put in rotation for 2 h at 37 degrees C. At the end of the experiments different parameters regarding platelet adhesion and activation were evaluated: circulating platelets count, beta-thromboglobulin release, platelet CD62P expression and amount of monocyte-platelet conjugates. PEtU-PDMS grafts with 25 and 40% of PDMS induced the lowest platelet adhesion, plasma level of beta-TG and amount of monocyte-platelet conjugates. No significative variations were observed in CD62P expression. In conclusion, PDMS content significatively affects blood-graft surface interaction, in fact higher PDMS percentage containing grafts showed the best in vitro hemocompatibility. PMID:17268875

  15. Risk Factors and Treatment Strategies in Patients With Retinal Vascular Occlusions.

    Science.gov (United States)

    Chapin, John; Carlson, Karen; Christos, Paul J; DeSancho, Maria Teresa

    2015-10-01

    Retinal vein occlusion (RVO) and retinal artery occlusion (RAO) cause significant visual impairment. The role of thrombophilia and cardiovascular testing is uncertain, and optimal treatment strategies have not been determined. We reviewed medical records of 39 patients with RVO and RAO (23 women and 16 men). Thrombophilia and cardiovascular evaluations were performed and outcomes were reviewed. In all, 24 (61.5%) patients had at least 1 thrombophilia. Elevated factor VIII levels were found in RVO (n = 5) but not in RAO. There are no other significant differences in thrombophilias in RVO compared to those in RAO. Most patients had hypertension(41.2% RAO and 55% RVO) and hyperlipidemia (35.5% RAO and 81.8% RVO). In all, 4 women were using oral contraceptives, 2 were pregnant or postpartum. Follow-up data was available for 28 patients (13 RAO, 15 RVO). Nineteen were treated with aspirin, four with warfarin, and one with low molecular weight heparin. Eight patients reported improvement in vision at time of follow-up (5 RAO, 3 RVO). Multiple risk factors are associated with RVO and RAO, and a complete assessment should include thrombophilia and cardiovascular studies. PMID:24335246

  16. Melatonin differentially affects vascular blood flow in humans

    OpenAIRE

    Cook, Jonathan S.; Sauder, Charity L.; Ray, Chester A.

    2010-01-01

    Melatonin is synthesized and released into the circulation by the pineal gland in a circadian rhythm. Melatonin has been demonstrated to differentially alter blood flow to assorted vascular beds by the activation of different melatonin receptors in animal models. The purpose of the present study was to determine the effect of melatonin on blood flow to various vascular beds in humans. Renal (Doppler ultrasound), forearm (venous occlusion plethysmography), and cerebral blood flow (transcranial...

  17. PHAGOCYTOSIS BY RETINAL PIGMENT EPITHELIAL CELLS IN VITRO IS AFFECTED BY EXPOSURE TO PESTICIDES.

    Science.gov (United States)

    Purpose:Agricultural and occupational exposures to the fungicides benomyl and captan and the insecticide fenthion have been associated with retinal degeneration. Exposure to insecticides has also been associated with pigmentary changes of the retina. Because retinal degeneration ...

  18. 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

  19. Systemic immunotherapy delays photoreceptor cell loss and prevents vascular pathology in Royal College of Surgeons rats

    OpenAIRE

    Adamus, Grazyna; Wang, Shaomei; Kyger, Madison; Worley, Aneta; Lu, Bin; Burrows, Gregory G.

    2012-01-01

    Purpose Degenerative retinopathies, including retinitis pigmentosa, age-related retinal degeneration, autoimmune retinopathy, and related diseases affect millions of people around the world. Currently, there is no effective treatment for most of those diseases. We investigated systemic recombinant T-cell receptor ligand (RTL) immunotherapy for preventing retinal degeneration and vascular damage in the Royal College of Surgeons (RCS) rat model of retinal degeneration. Methods RCS rats were tre...

  20. Retinal Vascular Fractals Correlate With Early Neurodegeneration in Patients With Type 2 Diabetes Mellitus

    DEFF Research Database (Denmark)

    Frydkjaer-Olsen, Ulrik; Soegaard Hansen, Rasmus; Pedersen, Knud;

    2015-01-01

    . In a randomly selected eye of each patient, Fd was calculated using SIVA-Fractal, a specialized semiautomatic software. Retinal neurodegeneration was evaluated by Topcon 3D OCT-2000 spectral-domain optical coherence tomography (OCT) and by a RETI-scan multifocal ERG (mf-ERG) system in rings one to...... ETDRS levels were 10 (42.7%), 20 (35.0%), and 35 (22.3%), respectively. Fd correlated inversely with mf-ERG implicit time of ring one (r = -0.25, P = 0.01) and present diabetic neuropathy (P = 0.02), and positively with OCT ganglion cell layer (GCL) thickness (r = 0.20, P = 0.04). In a multivariable...... linear regression model, Fd was associated with mf-ERG implicit time of ring one (coefficient -0.0021/ms, P = 0.040) and the presence of diabetic neuropathy (coefficient -0.0209 for neuropathy present versus absent, P = 0.041). Conclusions: In patients with T2DM and no or minimal DR, independent...

  1. N-3 polyunsaturated Fatty acids prevent diabetic retinopathy by inhibition of retinal vascular damage and enhanced endothelial progenitor cell reparative function.

    Directory of Open Access Journals (Sweden)

    Maria Tikhonenko

    Full Text Available OBJECTIVE: The vasodegenerative phase of diabetic retinopathy is characterized by not only retinal vascular degeneration but also inadequate vascular repair due to compromised bone marrow derived endothelial progenitor cells (EPCs. We propose that n-3 polyunsaturated fatty acid (PUFA deficiency in diabetes results in activation of the central enzyme of sphingolipid metabolism, acid sphingomyelinase (ASM and that ASM represents a molecular metabolic link connecting the initial damage in the retina and the dysfunction of EPCs. RESEARCH DESIGN AND METHODS: Type 2 diabetic rats on control or docosahexaenoic acid (DHA-rich diet were studied. The number of acellular capillaries in the retinas was assessed by trypsin digest. mRNA levels of interleukin (IL-1β, IL-6, intracellular adhesion molecule (ICAM-1 in the retinas from diabetic animals were compared to controls and ASM protein was assessed by western analysis. EPCs were isolated from blood and bone marrow and their numbers and ability to form colonies in vitro, ASM activity and lipid profiles were determined. RESULTS: DHA-rich diet prevented diabetes-induced increase in the number of retinal acellular capillaries and significantly enhanced the life span of type 2 diabetic animals. DHA-rich diet blocked upregulation of ASM and other inflammatory markers in diabetic retina and prevented the increase in ASM activity in EPCs, normalized the numbers of circulating EPCs and improved EPC colony formation. CONCLUSIONS: In a type 2 diabetes animal model, DHA-rich diet fully prevented retinal vascular pathology through inhibition of ASM in both retina and EPCs, leading to a concomitant suppression of retinal inflammation and correction of EPC number and function.

  2. 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.

  3. External Beam Radiotherapy for Head and Neck Cancers Is Associated with Increased Variability in Retinal Vascular Oxygenation

    OpenAIRE

    Higginson, Daniel S.; Sahgal, Alok; Lawrence, Michael V.; Moyer, Sarah; Stefanescu, Mihaela; Willson, Adam K.; Qaqish, Bahjat; Zanation, Adam; Marks, Lawrence B.; Garg, Seema; Chera, Bhishamjit S.

    2013-01-01

    Background Radiation retinopathy is a possible post-treatment complication of radiation therapy. The pathophysiologic mechanism is hypothesized to be microvascular in origin, but evidence is limited. In an effort to study retinal oxygenation in these patients, we herein evaluate the repeatability and variability of retinal oximetry measurements in subjects who had previously received radiation and make comparisons to a cohort of unirradiated subjects. Methods Using retinal oximetry, a non-inv...

  4. Cotton wool spots as possible indicators of retinal vascular pathology in ocular lyme borreliosis.

    Science.gov (United States)

    Klaeger, Andres J; Herbort, Carl P

    2010-10-01

    Lyme borreliosis is an underdiagnosed infectious disease caused by a spirochete and transmitted by certain Ixodes ticks. In Lyme disease diagnostic problems are still discussed extensively as the laboratory workup is not standardized and a positive antibody result is not proof of active infection. It is therefore important to appreciate all clinical signs that can prompt us to the diagnostic investigation of Lyme borreliosis. We present a case of a woman with Lyme borreliosis and recurrent unilateral anterior uveitis in her right eye for 2 years, who developed cotton wool spots (CWS) in her left eye, followed by acute and recurrent anterior uveitis in this second eye. An extensive general examination, including blood coagulopathies and ultrasound of the carotid arteries, did not reveal any pathology. The CWS resolved within a few months. The recurrent anterior uveitis could be controlled by topical steroids. After treatment with 2 g of i.v. ceftriaxone for 3 weeks, she remained free of recurrences for 1 year of observation time. CWS can be the first clinical sign of ocular vascular pathology and/or uveitis. Further investigation will be necessary to confirm the relationship between CWS and ocular borreliosis. In patients with otherwise unexplained CWS, the possibility of an infection with borreliosis should be ruled out carefully. PMID:18854948

  5. Intraocular cytokines in retinal vein occlusion and its relation to the efficiency of anti-vascular endothelial growth factor therapy

    Directory of Open Access Journals (Sweden)

    Andrey G Shchuko

    2015-01-01

    Full Text Available Purpose: To analyze the change in the concentration of intraocular cytokines (ICs in patients with retinal vein occlusion (RVO before and after intravitreal ranibizumab therapy (IVR, and to find the correlations of IC with clinical activity of RVO and efficiency of treatment. Materials and Methods: Forty-four patients aged 46–79 years old (mean age: 60.7 ± 7.5 years old with RVO and macular edema (18 patients – with central RVO, 26 – with branch RVO treated with IVR were included into the study. The concentrations of 27 cytokines were simultaneously measured in aqueous humor by flow fluorometry using Bio-Plex Pro Human Cytokine Panel, 27-Plex (Bio-Rad Laboratories, USA at baseline and after the first IVR. Control group consisted of 20 age-matched patients. Results: The levels of 11 cytokines (vascular endothelial growth factor [VEGF], receptor antagonist interleukin-1, interleukin-6 [IL-6], IL-8, IL-9, IL-10, IL-12r70, IL-13, IL-15, monocyte chemotactic protein-1 [MCP-1], regulated on activation, normal T expressed and secreted were significantly (P < 0.05 different compared to control and significantly (P < 0.05 changed after IVR both in central and branch RVO. The patients were divided into two groups: the first -"effective" and the second - "partially effective" therapy. The second group characterized by the higher concentrations of VEGF, IL-8, IL-10, IL-17, and MCP-1 at baseline compared to the first group. Conclusion: The patients with RVO were characterized by the increased levels of VEGF and other pro- and anti-inflammatory cytokines and chemokines. Aqueous concentration of cytokines were different in patients with central and branch RVO and significantly changed after IVR. Insufficient response to IVR was associated with activation of immune-inflammatory processes.

  6. Therapeutic potential of intravitreal pharmacotherapy in retinal vein occlusion

    OpenAIRE

    2012-01-01

    Retinal vein occlusion (RVO) is the most common visually disabling disease affecting the retina after diabetic retinopathy. Although the disease entity has long been known, its management is still controversial. Macular edema is the main reason for decreased visual acuity (VA) in this retinal vascular disorder. Recently the vitreous cavity has increasingly been used as a reservoir of drugs for the direct treatment of macular edema through intravitreal injection route. The most widely injected...

  7. Vaccination with a mutated variant of human Vascular Endothelial Growth Factor (VEGF) blocks VEGF-induced retinal neovascularization in a rabbit experimental model.

    Science.gov (United States)

    Morera, Yanelys; González, Rafael; Lamdan, Humberto; Pérez, Lincidio; González, Yorlandis; Agüero, Judith; Castro, Jorge; Romero, Juan C; Etchegoyen, Ana Yansy; Ayala, Marta; Gavilondo, Jorge V

    2014-05-01

    Vascular Endothelial Growth Factor (VEGF) is a key driver of the neovascularization and vascular permeability that leads to the loss of visual acuity of eye diseases like wet age-related macular degeneration, diabetic macular edema, and retinopathy of premature. Among the several anti-VEGF therapies under investigation for the treatment of neovascular eye diseases, our group has developed the vaccine candidate CIGB-247-V that uses a mutated form of human VEGF as antigen. In this work we evaluated if the vaccine could prevent or attenuate VEGF-induced retinal neovascularization in the course of a rabbit eye neovascularization model, based on direct intravitreal injection of human VEGF. Our experimental findings have shown that anti-VEGF IgG antibodies induced by the vaccine were available in the retina blood circulation, and could neutralize in situ the neovascularization effect of VEGF. CIGB-247-V vaccination proved to effectively reduce retinal neovascularization caused by intravitreal VEGF injection. Altogether, these results open the way for human studies of the vaccine in neovascular eye syndromes, and inform on the potential mechanisms involved in its effect. PMID:24675387

  8. Image enhancement for retinal vascular based on fractional differential%基于分数阶微分的视网膜血管图像增强

    Institute of Scientific and Technical Information of China (English)

    车进; 师一帅; 张成

    2012-01-01

    Starting from the enhanced ability of fractional differential to image details, the paper analyzes the mechanism of fractional differential, then constructs an approximate sixteen directions fractional differential template according to vector synthesis theorem and fractional differential difference function deduced by fractional calculus G-L definition, and uses the template to enhance retinal vascular image. The experimental results show, in response to those retinal vascular images which have rich textural detail information, fractional differential outperforms integral differential operation to extract the textural detail information in smooth region without too much gray scale change.%从分数阶微分对图像纹理细节的增强能力出发,对分数阶微分的机理进行分析,根据分数阶微积分的G-L定义推导出的差分公式与向量合成定理构建了近似的16方向分数阶微分模板,并将其应用于视网膜血管图像增强中.实验结果表明,对于纹理细节信息丰富的视网膜血管图像而言,分数阶微分对灰度变化不大的平坦区域中的纹理细节信息的提取效果明显优于整数阶微分运算.

  9. 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....

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

    Directory of Open Access Journals (Sweden)

    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.

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

    OpenAIRE

    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...

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

    Directory of Open Access Journals (Sweden)

    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.

  13. In search of underlying mechanisms and potential drugs of melphalan-induced vascular toxicity through retinal endothelial cells using bioinformatics approach.

    Science.gov (United States)

    Yang, Yang; Xing, Yiqiao; Liang, Chaoqun; Hu, Liya; Xu, Fei; Mei, Qi

    2016-05-01

    We aimed to explore molecular mechanism and drug candidates of vascular toxicities associated with melphalan after treating human retinal endothelial cells (RECs). GSE34381 microarray data was firstly downloaded and used to identify the differentially expressed genes (DEGs) in human REC treated with melphalan vs. untreated cells by limma package in R language. The transcription network was constructed based on TRANSFAC database and the top five transcription factors (TFs) were select with a measure of regulatory impact factor, followed by the construction of function modules. Gene ontology enrichment analyses were performed to explore the enriched functions. Connectivity Map analysis was conducted to predict the potential drugs overcoming the melphalan's actions on REC. Totally, 75 DEGs were identified, including 70 up-regulated and five down-regulated genes. Transcription network with 1311 nodes and 1875 edges was constructed and the top five TFs were CREM, MYC, FLI1, NF-κB1, and JUN. Functional modules indicated that NF-κB1 and MYC were the important nodes. The upregulated genes as well as the genes involved in the modules mainly participated in biological process of immune response, cell proliferation, and cell motion. Five small molecules were predicted to be potential drug candidates, including doxorubicin, fipexide, daunorubicin, tiabendazole, and GW-8510. Based on these results, we speculate that NF-κB1 and MYC might involve in the molecular mechanism of vascular toxicity induced by melphalan through regulating their target genes. Five small molecules might be drug candidates to overcome the melphalan-induced vascular toxicity via targeting to MYC and JUN. PMID:26662105

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

    Science.gov (United States)

    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. PMID:26642749

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

    Directory of Open Access Journals (Sweden)

    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.

  16. The retinal clock is altered in a mouse model of diabetic retinopathy

    OpenAIRE

    HASNA LAHOUAOUI; Christine Coutanson; Mohamed BENNIS

    2013-01-01

    The mammalian retina contains an endogenous pacemaker that regulates retinal physiology and adjusts daily the temporal phase of the central circadian timing system with environmental time. This entrainment process involves rods, cones and melanopsin-expressing retinal ganglion cells. Diabetic retinopathy is a major cause of blindness and visual impairment that affects up to 90% of patients with diabetes. Although vascular damage is considered the first clinical sign of retinopathy, several ...

  17. Retinal oximetry

    OpenAIRE

    Sveinn Hákon Harðarson 1978

    2012-01-01

    Purpose Malfunction of retinal blood flow or oxygenation is believed to be involved in various diseases. Among them are retinal vessel occlusions, diabetic retinopathy and glaucoma. Reliable, non-invasive technology for retinal oxygen measurements has been scarce and most of the knowledge on retinal oxygenation comes from animal studies. This thesis describes human retinal oximetry, performed with novel retinal oximetry technology. The thesis describes studies on retinal vessel oxygen satu...

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  20. 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.

  1. 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.

  2. Characterization of vascular lesions in pigs affected by porcine circovirus type 2-systemic disease.

    Science.gov (United States)

    Resendes, A R; Segalés, J

    2015-05-01

    Vascular lesions and their association with porcine circovirus type 2 (PCV2) were evaluated in multiple organs from 10 pigs affected with PCV2-systemic disease (PCV2-SD). Animals had vascular lesions in multiple organs, consisting of lymphohistiocytic lymphangitis and/or phlebitis, mild to severe necrotizing arteritis, and thrombosis within splenic arterioles and choroid plexus capillaries. Variable amounts of PCV2 nucleic acid detected by in situ hybridization were present within endothelial cells, tunica media myocytes, and perivascular and/or intralesional inflammatory cell infiltrates. PCV2 nucleic acid was detected within endothelial cells of both lymphatic and blood vessels without lesions in the associated tissues. Necrotizing arteritis was principally present in lymph nodes and kidney and consisted of degeneration, necrosis, and pyknosis of myocytes, often with intracytoplasmic, brightly eosinophilic inclusion bodies that were strongly positive for PCV2 nucleic acid. Segmental or circumferential fibrinoid necrosis was mainly present in vessels of the lymph node, spleen, and choroid plexus and was variably associated with PCV2 nucleic acid. Severe lymphangitis associated with strong intralesional PCV2 labeling was frequently detected within the mesenteric and mediastinal lymph nodes and the lamina propria of the ileum. In most tissues, medium and large lymphatics and/or veins often had disruption of the intima and mild mononuclear inflammatory cell infiltration that was variably associated with PCV2 nucleic acid. The present study indicates that vasculitis is a frequent finding in natural cases of PCV2-SD and that PCV2 may have a direct cytopathic effect on tunica media myocytes of small- and medium-sized arteries as well as endothelium. PMID:24963088

  3. 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.

  4. Clinical utilization of anti-vascular endothelial growth-factor agents and patient monitoring in retinal vein occlusion and diabetic macular edema

    Directory of Open Access Journals (Sweden)

    Kiss S

    2014-08-01

    .03; IVTA, 3.3 versus 3.0, P<0.05.Conclusion: During the study period (2008–2011, bevacizumab was the main anti-VEGF therapy used in clinical practice for BRVO, CRVO, and DME. Patients treated with bevacizumab were monitored less frequently and received fewer injections than patients in major clinical trials of ranibizumab. Keywords: anti-vascular endothelial growth factor, bevacizumab, ranibizumab, diabetic macular edema, retinal vein occlusion, intravitreal

  5. 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.

  6. Factors affecting the ability of the spectral domain optical coherence tomograph to detect photographic retinal nerve fiber layer defects.

    Directory of Open Access Journals (Sweden)

    Harsha L Rao

    Full Text Available To evaluate the ability of normative database classification (color-coded maps of spectral domain optical coherence tomograph (SDOCT in detecting wedge shaped retinal nerve fiber layer (RNFL defects identified on photographs and the factors affecting the ability of SDOCT in detecting these RNFL defects.In a cross-sectional study, 238 eyes (476 RNFL quadrants of 172 normal subjects and 85 eyes (103 RNFL quadrants with wedge shaped RNFL defects of 66 glaucoma patients underwent RNFL imaging with SDOCT. Logistic regression models were used to evaluate the factors associated with false positive and false negative RNFL classifications of the color-coded maps of SDOCT.False positive classification at a p value of <5% was seen in 108 of 476 quadrants (22.8%. False negative classification at a p value of <5% was seen in 16 of 103 quadrants (15.5%. Of the 103 quadrants with RNFL defects, 64 showed a corresponding VF defect in the opposite hemisphere and 39 were preperimetric. Higher signal strength index (SSI of the scan was less likely to have a false positive classification (odds ratio: 0.97, p = 0.01. Presence of an associated visual field defect (odds ratio: 0.17, p = 0.01 and inferior quadrant RNFL defects as compared to superior (odds ratio: 0.24, p = 0.04 were less likely to show false negative classifications.Scans with lower signal strengths were more likely to show false positive RNFL classifications, and preperimetric and superior quadrant RNFL defects were more likely to show false negative classifications on color-coded maps of SDOCT.

  7. 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

    -type channels are the dominant Ca(2+) entry pathway in vascular smooth muscle cells, however, T-type calcium channels are also expressed in the cardiovascular system where they play a functional role in the regulation of both contraction and vasodilation in (Chen et al. 2003; Hansen et al. 2001). This article......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...

  8. Interrelationships between the Retinal Neuroglia and Vasculature in Diabetes

    Directory of Open Access Journals (Sweden)

    Timothy S. Kern

    2014-06-01

    Full Text Available For years, diabetic retinopathy has been defined based on vascular lesions, and neural abnormalities were not regarded as important. This review summarizes evidence that the neural retina has important effects on the retinal vasculature under normal conditions, and the interaction between the retinal neuroglial cells and vascular function is altered in diabetes. Importantly, new evidence raises a possibility that abnormalities within retinal neuroglial cells (notably photoreceptors might actually be causing or initiating the vascular disease in diabetic retinopathy.

  9. Cell Swelling Contributes to Thickening of Low-Dose N-methyl-D-Aspartate–Induced Retinal Edema

    OpenAIRE

    Chen, Junjie; Chiang, Chia-Wen; Zhang, Huiying; Song, Sheng-Kwei

    2012-01-01

    Noninvasive magnetic resonance imaging was performed to detect retinal cell swelling in vivo. Our results demonstrated cell swelling could directly contribute to edematous retinal thickening independent of retinal vascular leakage.

  10. Neovascularização retiniana secundária a obstrução vascular em retinocoroidite por toxoplasmose em paciente HIV positivo: relato de caso Retinal vascular occlusion and neovascularization in acute toxoplasmic retinochoroiditis in a patient with AIDS: case report

    Directory of Open Access Journals (Sweden)

    Vânia Ewert

    2004-08-01

    Full Text Available Apresentar e discutir o caso de paciente infectado pelo HIV, que desenvolveu quadro de obstrução vascular seguido de neovascularização retiniana e de papila, durante o tratamento específico para retinocoroidite por toxoplasmose e que evoluiu com resolução espontânea da neovascularização sem a necessidade de tratamento associado. Paciente com retinocoroidite por toxoplasmose, que após 4 semanas de tratamento específico (sulfadiazina e pirimetamina desenvolveu quadro de obstrução vascular, seguido de neovascularização retiniana, apresentou involução espontânea, não havendo necessidade de fotocoagulação a laser, ou de outro tratamento adicional. As lesões retinianas ativas de toxoplasmose podem cursar com complicações vasculares, mesmo na vigência de tratamento específico, e geralmente apresentam bom prognóstico com regressão espontânea dos neovasos, sem necessidade de tratamentos adicionais.To present a case of an HIV-infected patient, who presented with active chorioretinal inflammatory lesion suggestive of toxoplasmosis, that during the specific treatment developed a retinal vascular occlusion, and adjacent neovascularization. 35-year-old AIDS patient that, presented with toxoplasmic retinochoroiditis and after 4 weeks of the specific therapy (pyrimethamine and sulfadiazine developed a vascular occlusion and retinal neovascularization that healed without the need for phototocoagulation or other adjunctive therapy. This case demonstrates that acute toxoplasmic retinochoroiditis that develops vascular complications may present a good result with the specific treatment without the need for adjunctive therapy.

  11. Rapid regression of exudative maculopathy in idiopathic retinitis, vasculitis, aneurysms and neuroretinitis syndrome after intravitreal ranibizumab.

    Science.gov (United States)

    Marín-Lambíes, Cristina; Gallego-Pinazo, Roberto; Salom, David; Navarrete, Javier; Díaz-Llopis, Manuel

    2012-05-01

    The idiopathic retinitis, vasculitis, aneurysms and neuroretinitis syndrome is a rare retinal vascular disorder characterized by multiple leaking aneurysmal dilations, retinal vasculitis, neuroretinitis and peripheral vascular ischemia. Visual loss mainly occurs due to the development of retinal neovascularization and/or exudative maculopathy. Although the treatment of choice has not yet been established, retinal photocoagulation seems to be the best option to control the disease and to prevent its progression. Herein, we report a case of idiopathic retinitis, vasculitis, aneurysms and neuroretinitis syndrome with both retinal neovascularization and macular exudation successfully managed with intravitreal ranibizumab (Lucentis(®)) as adjunctive therapy to retinal photocoagulation. PMID:22949913

  12. Cybersickness provoked by head-mounted display affects cutaneous vascular tone, heart rate and reaction time.

    Science.gov (United States)

    Nalivaiko, Eugene; Davis, Simon L; Blackmore, Karen L; Vakulin, Andrew; Nesbitt, Keith V

    2015-11-01

    Evidence from studies of provocative motion indicates that motion sickness is tightly linked to the disturbances of thermoregulation. The major aim of the current study was to determine whether provocative visual stimuli (immersion into the virtual reality simulating rides on a rollercoaster) affect skin temperature that reflects thermoregulatory cutaneous responses, and to test whether such stimuli alter cognitive functions. In 26 healthy young volunteers wearing head-mounted display (Oculus Rift), simulated rides consistently provoked vection and nausea, with a significant difference between the two versions of simulation software (Parrot Coaster and Helix). Basal finger temperature had bimodal distribution, with low-temperature group (n=8) having values of 23-29 °C, and high-temperature group (n=18) having values of 32-36 °C. Effects of cybersickness on finger temperature depended on the basal level of this variable: in subjects from former group it raised by 3-4 °C, while in most subjects from the latter group it either did not change or transiently reduced by 1.5-2 °C. There was no correlation between the magnitude of changes in the finger temperature and nausea score at the end of simulated ride. Provocative visual stimulation caused prolongation of simple reaction time by 20-50 ms; this increase closely correlated with the subjective rating of nausea. Lastly, in subjects who experienced pronounced nausea, heart rate was elevated. We conclude that cybersickness is associated with changes in cutaneous thermoregulatory vascular tone; this further supports the idea of a tight link between motion sickness and thermoregulation. Cybersickness-induced prolongation of reaction time raises obvious concerns regarding the safety of this technology. PMID:26340855

  13. Vascular endothelial growth factor and dexamethasone release from nonfouling sensor coatings affect the foreign body response

    OpenAIRE

    Norton, L.W.; Koschwanez, H.E.; Wisniewski, N.A.; Klitzman, B.; Reichert, W. M.

    2007-01-01

    Vascular endothelial growth factor (VEGF) and dexamethasone (DX) release from hydrogel coatings were examined as a means to modify tissue inflammation and induce angiogenesis. Antibiofouling hydrogels for implantable glucose sensor coatings were prepared from 2-hydro-xyethyl methacrylate, N-vinyl pyrrolidinone, and polyethylene glycol. Microdialysis sampling was used to test the effect of the hydrogel coating on glucose recovery. VEGF-releasing hydrogel-coated fibers increased vascularity and...

  14. Retinitis Pigmentosa

    Science.gov (United States)

    ... Congenital Amaurosis Macular Degeneration Retinitis Pigmentosa Stargardt Disease Usher Syndrome Other Retinal Diseases Glossary News & Research News & ... die. Forms of RP and related diseases include Usher syndrome, Leber’s congenital amaurosis, rod-cone disease, Bardet- ...

  15. Rapid Regression of Exudative Maculopathy in Idiopathic Retinitis, Vasculitis, Aneurysms and Neuroretinitis Syndrome after Intravitreal Ranibizumab

    OpenAIRE

    Marín-Lambíes, Cristina; Gallego-Pinazo, Roberto; Salom, David; Navarrete, Javier; Díaz-Llopis, Manuel

    2012-01-01

    The idiopathic retinitis, vasculitis, aneurysms and neuroretinitis syndrome is a rare retinal vascular disorder characterized by multiple leaking aneurysmal dilations, retinal vasculitis, neuroretinitis and peripheral vascular ischemia. Visual loss mainly occurs due to the development of retinal neovascularization and/or exudative maculopathy. Although the treatment of choice has not yet been established, retinal photocoagulation seems to be the best option to control the disease and to preve...

  16. 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.

  17. 视网膜血管直径与家族性高胆固醇血症的相关性研究%Retinal vascular caliber and the risk of familial hypercholesterolemia

    Institute of Scientific and Technical Information of China (English)

    高新晓; 孟忻; 蔺洁; 郭佳; 汪军

    2015-01-01

    目的 探讨视网膜血管直径与家族性高胆固醇血症(FH)的相关性.方法 选取2008年6月至2014年2月于首都医科大学附属北京安贞医院确诊为FH的21例患者为FH组,另外选取38例年龄、性别、血压和血糖相匹配的非FH正常者为对照组.通过彩色眼底照相及计算机辅助软件对视网膜动脉直径(CRAE)、视网膜静脉直径(CRVE)和视网膜动、静脉直径比值(AVR)分别进行测量.比较2组患者视网膜血管直径的测量值,并采用多元线性回归分析视网膜血管直径与FH的相关性.结果 2组患者性别、收缩压、舒张压、空腹血糖比较,差异无统计学意义(P>0.05).与对照组比较,FH组CRAE和AVR数值均明显降低[CRAE:(147 ±6)μm比(150±4)μm,AVR∶(0.65±0.05)比(0.69±0.08)],差异有统计学意义(P<0.05).2组患者的CRVE比较,差异无统计学意义(P=0.90).校正年龄及性别后,AVR减小与FH相关(P =0.03),FH越明显,AVR越小.结论 FH患者的AVR较正常人群减小,视网膜血管直径改变对FH具有一定提示作用.%Objective To examine the relation between retinal vascular caliber and familial hypercholesterolemia (FH).Methods We prospectively recruited 21 cases of FH and 38 control cases with matched age,gender,blood pressure and blood sugar from June 2008 to February 2014.Central retinal artery equivalent (CRAE),central retinal vein equivalent (CRVE) and arteriovenous ratio (AVR) were assessed from baseline retinal photographs using IVAN software.CRAE,CRVE and AVR were compared with the student t test between FH group and controls.Multiple linear regression analysis was performed to evaluate the correlation between retinal vascular caliber and FH.Results CRAE and AVR were decreased in FH group compared with controls[CRAE:(147 ± 6) μm vs (150 ± 4) μm,AVR:(0.65 ± 0.05) vs (0.69 ± 0.08)].The difference between the two groups was significant (P < 0.05).Decreased AVR was associated with FH (P =0.03) after controlling

  18. Bim is Responsible for the Inherent Sensitivity of the Developing Retinal Vasculature to Hyperoxia

    OpenAIRE

    Wang, Shoujian; Park, Sunyoung; Fei, Ping; Sorenson, Christine M.

    2011-01-01

    Apoptosis plays an important role in development and remodeling of vasculature during organogenesis. Coordinated branching and remodeling of the retinal vascular tree is essential for normal retinal function. Bcl-2 family members, such as bim can not only influence apoptosis, but also cell adhesive and migratory properties essential during vascular development. Here we examined the impact of bim deficiency on postnatal retinal vascularization, as well as retinal neovascularization during oxyg...

  19. Elk3 Deficiency Causes Transient Impairment in Post-Natal Retinal Vascular Development and Formation of Tortuous Arteries in Adult Murine Retinae

    OpenAIRE

    Christine Weinl; Christine Wasylyk; Marina Garcia Garrido; Vithiyanjali Sothilingam; Beck, Susanne C.; Heidemarie Riehle; Christine Stritt; Michel J Roux; Seeliger, Mathias W.; Bohdan Wasylyk; Alfred Nordheim

    2014-01-01

    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 E...

  20. 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.

  1. Risk factor profile in retinal detachment

    Directory of Open Access Journals (Sweden)

    Azad Raj

    1988-01-01

    Full Text Available 150 cases of retinal detachment comprising 50 patients each of bilateral retinal detachment, unilateral retinal detachment without any retinal lesions in the fellow eve and unilateral retinal detachment with retinal lesions in the fellow eye were studied and the various associated risk factors were statistically analysed. The findings are discussed in relation to their aetiological and prognostic significance in the different types of retinal detachment. Based on these observations certain guidelines are offered which may be of value in decision making, in prophylactic detachment surgery. Tractional breaks in the superior temporal quadrant especially when symptomatic. mandate prophylactic treatment. Urgency is enhanced it′ the patient is aphakic. Associated myopia adds to the urgency. The higher incidence of initial right e′ e involvement in all groups suggests a vascular original possibly ischaemic.

  2. Ischemic Retinal Vasculitis and Its Management

    Directory of Open Access Journals (Sweden)

    Lazha Talat

    2014-01-01

    Full Text Available Ischemic retinal vasculitis is an inflammation of retinal blood vessels associated with vascular occlusion and subsequent retinal hypoperfusion. It can cause visual loss secondary to macular ischemia, macular edema, and neovascularization leading to vitreous hemorrhage, fibrovascular proliferation, and tractional retinal detachment. Ischemic retinal vasculitis can be idiopathic or secondary to systemic disease such as in Behçet’s disease, sarcoidosis, tuberculosis, multiple sclerosis, and systemic lupus erythematosus. Corticosteroids with or without immunosuppressive medication are the mainstay treatment in retinal vasculitis together with laser photocoagulation of retinal ischemic areas. Intravitreal injections of bevacizumab are used to treat neovascularization secondary to systemic lupus erythematosus but should be timed with retinal laser photocoagulation to prevent further progression of retinal ischemia. Antitumor necrosis factor agents have shown promising results in controlling refractory retinal vasculitis excluding multiple sclerosis. Interferon has been useful to control inflammation and induce neovascular regression in retinal vasculitis secondary to Behçet’s disease and multiple sclerosis. The long term effect of these management strategies in preventing the progression of retinal ischemia and preserving vision is not well understood and needs to be further studied.

  3. 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.

  4. Interrelationships between the Retinal Neuroglia and Vasculature in Diabetes

    OpenAIRE

    Kern, Timothy S.

    2014-01-01

    For years, diabetic retinopathy has been defined based on vascular lesions, and neural abnormalities were not regarded as important. This review summarizes evidence that the neural retina has important effects on the retinal vasculature under normal conditions, and the interaction between the retinal neuroglial cells and vascular function is altered in diabetes. Importantly, new evidence raises a possibility that abnormalities within retinal neuroglial cells (notably photoreceptors) might act...

  5. Antihypertensive treatment differentially affects vascular sphingolipid biology in spontaneously hypertensive rats.

    Directory of Open Access Journals (Sweden)

    Léon J A Spijkers

    Full Text Available BACKGROUND: We have previously shown that essential hypertension in humans and spontaneously hypertensive rats (SHR, is associated with increased levels of ceramide and marked alterations in sphingolipid biology. Pharmacological elevation of ceramide in isolated carotid arteries of SHR leads to vasoconstriction via a calcium-independent phospholipase A(2, cyclooxygenase-1 and thromboxane synthase-dependent release of thromboxane A(2. This phenomenon is almost absent in vessels from normotensive Wistar Kyoto (WKY rats. Here we investigated whether lowering of blood pressure can reverse elevated ceramide levels and reduce ceramide-mediated contractions in SHR. METHODS AND FINDINGS: For this purpose SHR were treated for 4 weeks with the angiotensin II type 1 receptor antagonist losartan or the vasodilator hydralazine. Both drugs decreased blood pressure equally (SBP untreated SHR: 191±7 mmHg, losartan: 125±5 mmHg and hydralazine: 113±14 mmHg. The blood pressure lowering was associated with a 20-25% reduction in vascular ceramide levels and improved endothelial function of isolated carotid arteries in both groups. Interestingly, losartan, but not hydralazine treatment, markedly reduced sphingomyelinase-induced contractions. While both drugs lowered cyclooxygenase-1 expression, only losartan and not hydralazine, reduced the endothelial expression of calcium-independent phospholipase A(2. The latter finding may explain the effect of losartan treatment on sphingomyelinase-induced vascular contraction. CONCLUSION: In summary, this study corroborates the importance of sphingolipid biology in blood pressure control and specifically shows that blood pressure lowering reduces vascular ceramide levels in SHR and that losartan treatment, but not blood pressure lowering per se, reduces ceramide-mediated arterial contractions.

  6. Vascular endothelial growth factor signaling affects both angiogenesis and osteogenesis during the development of scleral ossicles.

    Science.gov (United States)

    Jabalee, James; Franz-Odendaal, Tamara A

    2015-10-01

    Intramembranous ossification is a complex multi-step process which relies on extensive interactions among bone cells and surrounding tissues. The embryonic vasculature is essential in regulating endochondral ossification; however, its role during intramembranous ossification remains poorly understood, and in vivo studies are lacking. Previous research from our lab on the development of the intramembranous scleral ossicles has demonstrated an intriguing pattern of vascular development in which the areas of future osteogenesis remain avascular until after bone induction has occurred. Such avascular zones are located directly beneath each of the conjunctival papillae, epithelial structures which provide osteogenic signals to the underlying mesenchyme. Here we provide a high-resolution map of the developing vasculature from the time of ossicle induction to mineralization using a novel technique. We show that vegfa is expressed by the papillae and nearby mesenchymal tissue throughout HH 34-37, when vascular growth is taking place, and is down-regulated thereafter. Localized inhibition of Vegf results in expansion of the avascular zone surrounding the implanted papilla and mispatterning of the scleral ossicles. These results demonstrate that Vegf signaling could provide important insights into the complex relationship between bone and vasculature during intramembranous bone development. PMID:26210172

  7. Retinal Detachment

    Science.gov (United States)

    ... are three different types of retinal detachment: Rhegmatogenous [reg-ma-TAH-jenous]—A tear or break in the retina allows fluid to get under the retina and separate it from the retinal pigment epithelium (RPE), the pigmented cell layer that nourishes the retina. These types of ...

  8. Arginase 2 deficiency reduces hyperoxia-mediated retinal neurodegeneration through the regulation of polyamine metabolism

    OpenAIRE

    S.P. Narayanan; Xu, Z.; Putluri, N; Sreekumar, A; Lemtalsi, T; Caldwell, R W; Caldwell, R B

    2014-01-01

    Hyperoxia treatment has been known to induce neuronal and glial death in the developing central nervous system. Retinopathy of prematurity (ROP) is a devastating disease in premature infants and a major cause of childhood vision impairment. Studies indicate that, in addition to vascular injury, retinal neurons are also affected in ROP. Using an oxygen-induced retinopathy (OIR) mouse model for ROP, we have previously shown that deletion of the arginase 2 (A2) significantly reduced neuro-glial ...

  9. 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

    CNV adherent 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...

  10. 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/2JBax+/− mice exhibited complete resistance to nerve damage after 2 weeks (similar to Bax−/− mice, but 129B6Bax+/− 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.

  11. Sequential bilateral retinal artery occlusion

    Directory of Open Access Journals (Sweden)

    Padrón-Pérez N

    2014-04-01

    Full Text Available Noel Padrón-Pérez,1 Janny Rosario Aronés,2 Silvia Muñoz,1 Luis Arias-Barquet,1 Jorge Arruga1,31Department of Ophthalmology, Hospital Universitari de Bellvitge, 2Hospital de l'Esperança – Parc de Salut Mar, 3Institut Català de Retina, Barcelona, SpainAbstract: An 86 year old woman experienced a sequential bilateral loss of vision over a period of less than 24 hours. Clinical findings and complementary studies suggested a bilateral atherogenic embolic event. Initially, she presented a superior branch retinal artery occlusion in her right eye followed by a central retinal artery occlusion with cilioretinal artery sparing in her left eye. Some conservative maneuvers performed did not improve visual acuity in the left eye. Supra-aortic Doppler ultrasonography revealed mild right internal carotid artery stenosis and moderate left internal carotid artery stenosis with a small, smooth, and homogeneous plaque. The transthoracic echocardiography showed a severe calcification of the mitral valve with a mild-moderate rim of stenosis. Central retinal artery occlusion and branch retinal artery occlusion are characterized by painless monocular loss of vision. Clinical approach and management attempt to treat the acute event, find the source of the vascular occlusion, and prevent further vascular events from occurring. Giant cell arteritis is a potentially treatable cause of central retinal artery occlusion and should be excluded in every single patient over 50 years old.Keywords: loss of vision, branch retinal artery occlusion, central retinal artery occlusion, Hollenhorst plaque

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

    Directory of Open Access Journals (Sweden)

    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

  13. CLINICAL STUDY OF RETINAL VEIN OCCLUSIONS AND MANAGEMENT

    Directory of Open Access Journals (Sweden)

    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

  14. 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.

  15. Hypoxia and the Presence of Human Vascular Endothelial Cells Affect Prostate Cancer Cell Invasion and Metabolism

    Directory of Open Access Journals (Sweden)

    Ellen Ackerstaff

    2007-12-01

    Full Text Available Tumor progression and metastasis are influenced by hypoxia, as well as by interactions between cancer cells and components of the stroma, such as endothelial cells. Here, we have used a magnetic resonance (MRcompatible invasion assay to further understand the effects of hypoxia on human prostate cancer cell invasion and metabolism in the presence and absence of human umbilical vein endothelial cells (HUVECs. Additionally, we compared endogenous activities of selected proteases related to invasion in PC-3 cells and HUVECs, profiled gene expression of PC-3 cells by microarray, evaluated cell proliferation of PC-3 cells and HUVECs by flow cytometry, under hypoxic and oxygenated conditions. The invasion of less-invasive DU-145 cells was not affected by either hypoxia or the presence of HUVECs. However, hypoxia significantly decreased the invasion of PC-3 cells. This hypoxia-induced decrease was attenuated by the presence of HUVECs, whereas under oxygenated conditions, HUVECs did not alter the invasion of PC-3 cells. Cell metabolism changed distinctly with hypoxia and invasion. The endogenous activity of selected extracellular proteases, although altered by hypoxia, did not fully explain the hypoxia-induced changes in invasion. Gene expression profiling indicated that hypoxia affects multiple cellular functions and pathways.

  16. Ophthalmic drug discovery: novel targets and mechanisms for retinal diseases and glaucoma.

    Science.gov (United States)

    Zhang, Kang; Zhang, Liangfang; Weinreb, Robert N

    2012-07-01

    Blindness affects 60 million people worldwide. The leading causes of irreversible blindness include age-related macular degeneration, retinal vascular diseases and glaucoma. The unique features of the eye provide both benefits and challenges for drug discovery and delivery. During the past decade, the landscape for ocular drug therapy has substantially changed and our knowledge of the pathogenesis of ophthalmic diseases has grown considerably. Anti-angiogenic drugs have emerged as the most effective form of therapy for age-related macular degeneration and retinal vascular diseases. Lowering intraocular pressure is still the mainstay for glaucoma treatment but neuroprotective drugs represent a promising next-generation therapy. This Review discusses the current state of ocular drug therapy and highlights future therapeutic opportunities. PMID:22699774

  17. Multiple dietary supplements do not affect metabolic and cardio-vascular health.

    Science.gov (United States)

    Soare, Andreea; Weiss, Edward P; Holloszy, John O; Fontana, Luigi

    2014-02-01

    Dietary supplements are widely used for health purposes. However, little is known about the metabolic and cardiovascular effects of combinations of popular over-the-counter supplements, each of which has been shown to have anti-oxidant, anti-inflammatory and pro-longevity properties in cell culture or animal studies. This study was a 6-month randomized, single-blind controlled trial, in which 56 non-obese (BMI 21.0-29.9 kg/m(2)) men and women, aged 38 to 55 yr, were assigned to a dietary supplement (SUP) group or control (CON) group, with a 6-month follow-up. The SUP group took 10 dietary supplements each day (100 mg of resveratrol, a complex of 800 mg each of green, black, and white tea extract, 250 mg of pomegranate extract, 650 mg of quercetin, 500 mg of acetyl-l-carnitine, 600 mg of lipoic acid, 900 mg of curcumin, 1 g of sesamin, 1.7 g of cinnamon bark extract, and 1.0 g fish oil). Both the SUP and CON groups took a daily multivitamin/mineral supplement. The main outcome measures were arterial stiffness, endothelial function, biomarkers of inflammation and oxidative stress, and cardiometabolic risk factors. Twenty-four weeks of daily supplementation with 10 dietary supplements did not affect arterial stiffness or endothelial function in nonobese individuals. These compounds also did not alter body fat measured by DEXA, blood pressure, plasma lipids, glucose, insulin, IGF-1, and markers of inflammation and oxidative stress. In summary, supplementation with a combination of popular dietary supplements has no cardiovascular or metabolic effects in non-obese relatively healthy individuals. PMID:24659610

  18. Retinal vein occlusion in Benin City, Nigeria

    OpenAIRE

    Uhumwangho, Odarosa M.; Darlingtess Oronsaye

    2016-01-01

    Background: Retinal vein occlusion (RVO) is the most common occlusive retinal vascular disorder and results in varying degrees of visual loss. Aim: To determine the pattern of presentation, risk factors, and treatment outcomes in a group of patients with RVO seen in a tertiary hospital in Nigeria. Materials and Methods: Medical records of patients who presented to the University of Benin Teaching Hospital, Benin City, Nigeria in whom a diagnosis of RVO was made over a 5 years period were revi...

  19. Combined branch retinal vein and artery occlusion in toxoplasmosis.

    Science.gov (United States)

    Aggio, Fabio Bom; Novelli, Fernando José de; Rosa, Evandro Luis; Nobrega, Mário Junqueira

    2016-01-01

    A 22-year-old man complained of low visual acuity and pain in his left eye for five days. His ophthalmological examination revealed 2+ anterior chamber reaction and a white, poorly defined retinal lesion at the proximal portion of the inferotemporal vascular arcade. There were retinal hemorrhages in the inferotemporal region extending to the retinal periphery. In addition, venous dilation, increased tortuosity, and ischemic retinal whitening along the inferotemporal vascular arcade were also observed. A proper systemic work-up was performed, and the patient was diagnosed with ocular toxoplasmosis. He was treated with an anti-toxoplasma medication, and his condition slowly improved. Inferior macular inner and middle retinal atrophy could be observed on optical coherence tomography as a sequela of ischemic injury. To our knowledge, this is the first report of combined retinal branch vein and artery occlusion in toxoplasmosis resulting in a striking and unusual macular appearance. PMID:27463632

  20. Reliability of retinal vessel calibre measurements using a retinal oximeter

    OpenAIRE

    Heitmar, Rebekka; Kalitzeos, Angelos A.

    2015-01-01

    Background Summarised retinal vessel diameters are linked to systemic vascular pathology. Monochromatic images provide best contrast to measure vessel calibres. However, when obtaining images with a dual wavelength oximeter the red-free image can be extracted as the green channel information only which in turn will reduce the number of photographs taken at a given time. This will reduce patient exposure to the camera flash and could provide sufficient quality images to reliably measure vessel...

  1. Amyloidosis in Retinal Neurodegenerative Diseases

    Science.gov (United States)

    Masuzzo, Ambra; Dinet, Virginie; Cavanagh, Chelsea; Mascarelli, Frederic; Krantic, Slavica

    2016-01-01

    As a part of the central nervous system, the retina may reflect both physiological processes and abnormalities related to pathologies that affect the brain. Amyloidosis due to the accumulation of amyloid-beta (Aβ) was initially regarded as a specific and exclusive characteristic of neurodegenerative alterations seen in the brain of Alzheimer’s disease (AD) patients. More recently, it was discovered that amyloidosis-related alterations, similar to those seen in the brain of Alzheimer’s patients, also occur in the retina. Remarkably, these alterations were identified not only in primary retinal pathologies, such as age-related macular degeneration (AMD) and glaucoma, but also in the retinas of Alzheimer’s patients. In this review, we first briefly discuss the biogenesis of Aβ, a peptide involved in amyloidosis. We then discuss some pathological aspects (synaptic dysfunction, mitochondrial failure, glial activation, and vascular abnormalities) related to the neurotoxic effects of Aβ. We finally highlight common features shared by AD, AMD, and glaucoma in the context of Aβ amyloidosis and further discuss why the retina, due to the transparency of the eye, can be considered as a “window” to the brain. PMID:27551275

  2. Acquired retinal folds in the cat.

    Science.gov (United States)

    MacMillan, A D

    1976-06-01

    Retinal folds were found in 5 cats. The apparent cause of the folding was varied: in 1 cat the folds appeared after a localized retinal detachment; in 2 cats the condition accompanied other intraocular abnormalities associated with feline infectious peritonitis; 1 cat had active keratitis, and the retinal changes were thought to have been injury related; and 1 cat, bilaterally affected, had chronic glomerulonephritis. PMID:945253

  3. 联合方法治疗新生血管性青光眼疗效观察%Compound T rabeculectomy and Retinal Photocoagulation and Vitreous Injection Ranibizumab in the M anagement of New Vascular Glaucoma

    Institute of Scientific and Technical Information of China (English)

    林芳; 齐美华; 赵静

    2015-01-01

    Objective To comparatively evaluate the efficacy and safety profiles of compound trabeculecto-my and Retinal photocoagulation and Vitreous injection Ranibizumab in the management of New vascular glauco-ma .Method Clinical records of 8 patients (8 eyes) with New vascular glaucoma secondary to RVO whose fun-dus oculi can be watched to be treated with Retinal laser photocoagulation first the pathants were threated with Retinal laser photocoagulation ,the second were Vitreous injection Ranibizumab seven days with compound tra-beculectomy after surgery ,according to patients iop and Anterior chamber to teach patients to learning Eye mas-sage?Record visions ,central macular thickness(CM T ) ,intraocular pressure(IOP) ,the degrade of Retinal neo-vascularization of fundus oculi and new vessels changes of iris and angles in Preoperative and postoperative 3 months ,6 months ,1 2 months .Result The Vision:3 months:(0 .0 4 ± 0 .0 4 ) ,6 months:(0 .0 6 ± 0 .0 5 ) ,1 2 months:(0 .0 5 ± 0 .0 4 ) ,4 eye’s Vision were improved 3 eye’s Vision werenot improved .The one eye is No light perception .IOP:3 months:(1 3 .2 4 ± 2 .2 3 )mmhg ,6 months:(1 5 .4 ± 2 3 .4 2 )mmhg ,1 2 months:(1 8 .2 5 ± 3 .1 5 ) mmhg ,6 patients can controled IOP under 2 1 mmhg ,postoperative one patient iop can be controled in normal in first 3 months ,give Alphagan eye water in rising to 2 1 mmhg of iop ,iop can be control in 1 8 mmhg ,6 months lat-er the iop rise to 1 9 mmhg ,in 9 months the iop rised to 2 1 mmhg ,Brinzolamide eye water was used ,iop can be control in 2 0 mmhg ,in 1 2 months ,iop is 2 2 mmhg ,2 2 mmhg ,in Process ,the patient Supplement Retinal photo-coagulation twice new vessels changes of iris and angles:5 cases degrade ,3 cases Reduce ,FFA :Capillary zone de-grade of 5 cases;Capillary zone degrade of 3 cases in Supplement Retinal laser photocoagulation ,CM T :Before treatment and1 week ,2 weeks ,4 weeks ,8 weeks ,1 2 weeks after Vitreous cavity injection was:(4 4 0 .3 6 ± 5 0

  4. Retinal vein occlusion

    Science.gov (United States)

    Central retinal vein occlusion; Branch retinal vein occlusion; CRVO; BRVO ... Retinal vein occlusion is most often caused by hardening of the arteries ( atherosclerosis ) and the formation of a blood clot. Blockage ...

  5. 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.

  6. Current perspectives of herpesviral retinitis and choroiditis.

    Science.gov (United States)

    Madhavan, H N; Priya, K; Biswas, J

    2004-10-01

    Vision-threatening viral retinitis are primarily caused by members of the herpesvirus family. The biology and molecular characterization of herpesviruses, clinical presentations of retinopathies, pathology and pathogenesis including the host responses, epidemiology and the laboratory methods of aetiological diagnosis of these diseases are described. Clinical syndromes are acute retinal necrosis (ARN), progressive outer retinal necrosis (PORN), cytomegalovirus (CMV) retinitis, multifocal choroiditis and serpiginous choroiditis besides other viral retinopathies. Herpes simplex virus (HSV) retinitis is more common in immunocompetent persons while varicella zoster virus (VZV) affects both immunocompetent and immunosuppressed patients equally. CMV retinitis is most common among patients with AIDS. The currently employed laboratory methods of antigen detection, virus isolation and antibody detection by enzyme linked immuno-sorbent assay (ELISA) have low sensitivity. Polymerase chain reaction (PCR) has increased the value of diagnosis due to its high clinical sensitivity and absolute specificity in detection of herpesviruses in intraocular specimens. PMID:16295367

  7. Retinal vein occlusion: current treatment.

    Science.gov (United States)

    Lattanzio, Rosangela; Torres Gimeno, Ana; Battaglia Parodi, Maurizio; Bandello, Francesco

    2011-01-01

    Retinal vein occlusion (RVO) is a pathology noted for more than 150 years. Although a lot has been written on the matter, it is still a frequent condition with multifactorial etiopathogenesis with many unclear aspects. The RVO pathogenesis has varied systemic and local implications that make it difficult to elaborate treatment guidelines. The management of the patient with RVO is very complex and a multidisciplinary approach is required in order to identify and correct the associated risk factors. Laser therapy remains the gold standard in RVO, but only modest functional improvement has been shown in branch retinal occlusion forms. Multicenter studies of intravitreal drugs present them as an option to combine with laser. Anti-vascular endothelial growth factor, corticosteroids and sustained-release implants are the future weapons to stop disease progression and get a better visual outcome. Consequently, it is useful to clarify some aspects of the pathology that allow a better patient management. PMID:20938213

  8. Low IGF-I suppresses VEGF-survival signaling in retinal endothelial cells: Direct correlation with clinical retinopathy of prematurity

    OpenAIRE

    Hellstrom, Ann; Perruzzi, Carole; Ju, Meihua; Engström, Eva; Hård, Anna-Lena; Liu, Jun-Li; Albertsson-Wikland, Kerstin; Carlsson, Björn; Niklasson, Aimon; Sjödell, Lena; LeRoith, Derek; Senger, Donald R.; Smith, Lois E. H.

    2001-01-01

    Retinopathy of prematurity is a blinding disease, initiated by lack of retinal vascular growth after premature birth. We show that lack of insulin-like growth factor I (IGF-I) in knockout mice prevents normal retinal vascular growth, despite the presence of vascular endothelial growth factor, important to vessel development. In vitro, low levels of IGF-I prevent vascular endothelial growth factor-induced activation of protein kinase B (Akt), a kinase critical for e...

  9. RNA-binding protein Hermes/RBPMS inversely affects synapse density and axon arbor formation in retinal ganglion cells in vivo.

    Science.gov (United States)

    Hörnberg, Hanna; Wollerton-van Horck, Francis; Maurus, Daniel; Zwart, Maarten; Svoboda, Hanno; Harris, William A; Holt, Christine E

    2013-06-19

    The RNA-binding protein Hermes [RNA-binding protein with multiple splicing (RBPMS)] is expressed exclusively in retinal ganglion cells (RGCs) in the CNS, but its function in these cells is not known. Here we show that Hermes protein translocates in granules from RGC bodies down the growing axons. Hermes loss of function in both Xenopus laevis and zebrafish embryos leads to a significant reduction in retinal axon arbor complexity in the optic tectum, and expression of a dominant acting mutant Hermes protein, defective in RNA-granule localization, causes similar defects in arborization. Time-lapse analysis of branch dynamics reveals that the decrease in arbor complexity is caused by a reduction in new branches rather than a decrease in branch stability. Surprisingly, Hermes depletion also leads to enhanced early visual behavior and an increase in the density of presynaptic puncta, suggesting that reduced arborization is accompanied by increased synaptogenesis to maintain synapse number. PMID:23785151

  10. 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.

  11. Vascular Cures

    Science.gov (United States)

    ... our CEO Board of Directors Scientific Advisory Board History of Vascular Cures Impact Contact Us Vascular Disease What is Vascular Disease? Education and Awareness Vascular Diseases Abdominal Aortic Aneurysm Aortic ...

  12. Aggressive retinal astrocytoma associated with tuberous sclerosis

    Directory of Open Access Journals (Sweden)

    Tomida M

    2012-05-01

    Full Text Available Machiko Tomida,1 Yoshinori Mitamura,1 Takashi Katome,1 Hiroshi Eguchi,1 Takeshi Naito,1 Takayuki Harada21Department of Ophthalmology, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima, 2Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, JapanAbstract: We report the case of a patient with an aggressive retinal astrocytoma accompanied with macular edema and neovascular vessels, who was initially treated with intravitreal bevacizumab injections. A 24-year-old male presented to our clinic complaining of visual disturbance in his right eye. At 8 years of age, he had been diagnosed as having tuberous sclerosis complex. Fundus examination demonstrated a retinal tumor accompanied with marked neovascular vessels on the surface, retinal hemorrhage, and macular edema. After six monthly intravitreal bevacizumab injections, fundus examination demonstrated marked regression of the macular edema and neovascular vessels. Two months later, a vitreous hemorrhage developed which necessitated pars plana vitrectomy. After additional intravitreal bevacizumab injection for preventing intraoperative bleeding, vitrectomy with endophotocoagulation for the tumor was performed. The vitreous sample was obtained during vitrectomy, and we measured the vascular endothelial growth factor concentration by enzyme-linked immunosorbent assay. The surgically removed epiretinal neovascular membrane and biopsied retinal tumor expressed vascular endothelial growth factor, although several intravitreal bevacizumab injections led to a vitreous vascular endothelial growth factor concentration of undetectable levels. The clinical course and immunohistochemical analyses indicate that intravitreal bevacizumab monotherapy may have been insufficient to treat the aggressive retinal astrocytoma with macular edema and that laser photocoagulation or photodynamic therapy for the tumor should be considered following intravitreal

  13. Arginase 2 deletion reduces neuro-glial injury and improves retinal function in a model of retinopathy of prematurity.

    Directory of Open Access Journals (Sweden)

    Subhadra P Narayanan

    Full Text Available BACKGROUND: Retinopathy of prematurity (ROP is a major cause of vision impairment in low birth weight infants. While previous work has focused on defining the mechanisms of vascular injury leading to retinal neovascularization, recent studies show that neurons are also affected. This study was undertaken to determine the role of the mitochondrial arginine/ornithine regulating enzyme arginase 2 (A2 in retinal neuro-glial cell injury in the mouse model of ROP. METHODS AND FINDINGS: Studies were performed using wild type (WT and A2 knockout (A2-/- mice exposed to Oxygen Induced Retinopathy (OIR. Neuronal injury and apoptosis were assessed using immunohistochemistry, TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labeling and Western blotting. Electroretinography (ERG was used to assess retinal function. Neuro-glial injury in WT ROP mice was evident by TUNEL labeling, retinal thinning, decreases in number of rod bipolar cells and glial cell activation as compared with room air controls. Significant reduction in numbers of TUNEL positive cells, inhibition of retinal thinning, preservation of the rod bipolar cells and prevention of glial activation were observed in the A2-/- retinas. Retinal function was markedly impaired in the WT OIR mice as shown by decreases in amplitude of the b-wave of the ERG. This defect was significantly reduced in A2-/- mice. Levels of the pro-apoptotic proteins p53, cleaved caspase 9, cytochrome C and the mitochondrial protein Bim were markedly increased in WT OIR retinas compared to controls, whereas the pro-survival Mitochondrial protein BCL-xl was reduced. These alterations were largely blocked in the A2-/- OIR retina. CONCLUSIONS: Our data implicate A2 in neurodegeneration during ROP. Deletion of A2 significantly improves neuronal survival and function, possibly through the regulation of mitochondrial membrane permeability mediated apoptosis during retinal ischemia. These molecular events are associated with

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

    Science.gov (United States)

    Wang, Haibo; Han, Xiaokun; Gambhir, Deeksha; Becker, Silke; Kunz, Eric; Liu, Angelina Jingtong; Hartnett, M Elizabeth

    2016-01-01

    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 inhibition

  15. Cre recombinase expression or topical tamoxifen treatment do not affect retinal structure and function, neuronal vulnerability or glial reactivity in the mouse eye.

    Science.gov (United States)

    Boneva, S K; Groß, T R; Schlecht, A; Schmitt, S I; Sippl, C; Jägle, H; Volz, C; Neueder, A; Tamm, E R; Braunger, B M

    2016-06-14

    Mice with a constitutive or tamoxifen-induced Cre recombinase (Cre) expression are frequently used research tools to allow the conditional deletion of target genes via the Cre-loxP system. Here we analyzed for the first time in a comprehensive and comparative way, whether retinal Cre expression or topical tamoxifen treatment itself would cause structural or functional changes, including changes in the expression profiles of molecular markers, glial reactivity and photoreceptor vulnerability. To this end, we characterized the transgenic α-Cre, Lmop-Cre and the tamoxifen-inducible CAGG-CreER™ mouse lines, all having robust Cre expression in the neuronal retina. In addition, we characterized the effects of topical tamoxifen treatment itself in wildtype mice. We performed morphometric analyses, immunohistochemical staining, in vivo ERG and angiography analyses and realtime RT-PCR analyses. Furthermore, the influence of Cre recombinase or topical tamoxifen exposure on neuronal vulnerability was studied by using light damage as a model for photoreceptor degeneration. Taken together, neither the expression of Cre, nor topical tamoxifen treatment caused detectable changes in retinal structure and function, the expression profiles of investigated molecular markers, glial reactivity and photoreceptor vulnerability. We conclude that the Cre-loxP system and its induction through tamoxifen is a safe and reliable method to delete desired target genes in the neural retina. PMID:27026593

  16. The factors affecting outcome after non-vascular bone grafting and internal fixation for nonunion of the scaphoid.

    Science.gov (United States)

    Ramamurthy, C; Cutler, L; Nuttall, D; Simison, A J M; Trail, I A; Stanley, J K

    2007-05-01

    This study identified variables which influence the outcome of surgical management on 126 ununited scaphoid fractures managed by internal fixation and non-vascular bone grafting. The site of fracture was defined by a new method: the ratio of the length of the proximal fragment to the sum of the lengths of both fragments, calculated using specific views in the plain radiographs. Bone healing occurred in 71% (89) of cases. Only the site of nonunion (p = 1 x 10(-6)) and the delay to surgery (p = 0.001) remained significant on multivariate analysis. The effect of surgical delay on the probability of union increased as the fracture site moved proximally. A prediction model was produced by stepwise logistic regression analysis, enabling the surgeon to predict the success of surgery where the site of the nonunion and delay to surgery is known. PMID:17540748

  17. 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.

  18. Multiple extra macular branch retinal vein occlusions in hyperhomocysteinemia

    Directory of Open Access Journals (Sweden)

    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.

  19. Cytometric analysis of retinopathies in retinal trypsin digests

    Science.gov (United States)

    Ghanian, Zahra; Staniszewski, Kevin; Sorenson, Christine M.; Sheibani, Nader; Ranji, Mahsa

    2014-03-01

    The objective of this work was to design an automated image cytometry tool for determination of various retinal vascular parameters including extraction of features that are relevant to postnatal retinal vascular development, and the progression of diabetic retinopathy. To confirm the utility and accuracy of the software, retinal trypsin digest from TSP1-/- and diabetic Akita/+; TSP1-/- mice were analyzed. TSP1 is a critical inhibitor of development of retinopathies and lack of TSP1 exacerbates progression of early diabetic retinopathies. Loss of vascular cells of and gain more acellular capillaries as two major signs of diabetic retinopathies were used to classify a retina as normal or injured. This software allows quantification and high throughput assessment of retinopathy changes associated with diabetes.

  20. The expression and function of vascular endothelial growth factor in retinal pigment epithelial (RPE) cells is regulated by 4-hydroxynonenal (HNE) and glutathione S-transferaseA4-4

    Energy Technology Data Exchange (ETDEWEB)

    Vatsyayan, Rit; Lelsani, Poorna Chandra Rao; Chaudhary, Pankaj; Kumar, Sushil; Awasthi, Sanjay [Department of Molecular Biology and Immunology, University of North Texas Health Science Center, Fort Worth, TX 76107 (United States); Awasthi, Yogesh C., E-mail: Yogesh.Awasthi@unthsc.edu [Department of Molecular Biology and Immunology, University of North Texas Health Science Center, Fort Worth, TX 76107 (United States)

    2012-01-06

    Highlights: Black-Right-Pointing-Pointer Low concentration of HNE (0.1-1.0 {mu}M) induced secretion of VEGF in RPE cells. Black-Right-Pointing-Pointer VEGF secreted medium of RPE cells promoted proliferation of endothelial cells. Black-Right-Pointing-Pointer VEGFR2 expression was attenuated with increasing concentrations of HNE. Black-Right-Pointing-Pointer These effects of HNE could be blocked by the over expression of GSTA4-4 in cells. -- Abstract: It is well established that 4-hydroxynonenal (HNE) plays a major role in oxidative stress-induced signaling and the toxicity of oxidants. Surprisingly our recent studies also demonstrate that low levels of HNE generated during oxidative stress promote cell survival mechanisms and proliferation. Since the expression and secretion of VEGF is known to be affected by Oxidative stress, during present studies, we have examined dose dependent effect of HNE on VEGF expression and secretion in a model of retinal pigment epithelial (RPE) cells in culture. Results of these studies showed that while inclusion of 0.1 {mu}M HNE in the medium caused increased secretion of VEGF, its secretion and expression was significantly suppressed in the presence of >5 {mu}M HNE in the media. These concentration dependent hormetic effects of HNE on VEGF secretion could be blocked by the over expression of GSTA4-4 indicating that these effects were specifically attributed to HNE and regulated by GSTA4-4. VEGF secreted into the media showed angiogenic properties as indicated by increased migration and tube formation of HUVEC in matrigel when grown in media from RPE cells treated with 1 {mu}M HNE. The corresponding media from GSTA4-4 over expressing RPE cells had no effect on migration and tube formation of HUVEC in matrigel. These results are consistent with earlier studies showing that at low concentrations, HNE promotes proliferative mechanisms and suggest that HNE induces VEGF secretion from RPE cells that acts in a paracrine fashion to induce

  1. Marfan Syndrome Presenting with Bilateral Retinal Detachment

    OpenAIRE

    Subrata Chakrabarti; Koushik Pan

    2014-01-01

    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...

  2. Automated measurement of retinal blood vessel tortuosity

    Science.gov (United States)

    Joshi, Vinayak; Reinhardt, Joseph M.; Abramoff, Michael D.

    2010-03-01

    Abnormalities in the vascular pattern of the retina are associated with retinal diseases and are also risk factors for systemic diseases, especially cardiovascular diseases. The three-dimensional retinal vascular pattern is mostly formed congenitally, but is then modified over life, in response to aging, vessel wall dystrophies and long term changes in blood flow and pressure. 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. We developed a new quantitative metric for vascular tortuosity, based on the vessel's angle of curvature, length of the curved vessel over its chord length (arc to chord ratio), number of curvature sign changes, and combined these into a unidimensional metric, Tortuosity Index (TI). In comparison to other published methods this method can estimate appropriate TI for vessels with constant curvature sign and vessels with equal arc to chord ratios, as well. We applied this method to a dataset of 15 digital fundus images of 8 patients with Facioscapulohumeral muscular dystrophy (FSHD), and to the other publically available dataset of 60 fundus images of normal cases and patients with hypertensive retinopathy, of which the arterial and venous tortuosities have also been graded by masked experts (ophthalmologists). The method produced exactly the same rank-ordered list of vessel tortuosity (TI) values as obtained by averaging the tortuosity grading given by 3 ophthalmologists for FSHD dataset and a list of TI values with high ranking correlation with the ophthalmologist's grading for the other dataset. Our results show that TI has potential to detect and evaluate abnormal retinal vascular structure in early diagnosis and prognosis of retinopathies.

  3. Prevention and treatment of peritoneal adhesions in patients affected by vascular diseases following surgery: a review of the literature

    Directory of Open Access Journals (Sweden)

    Rocca Aldo

    2016-06-01

    Full Text Available Intra-abdominal adhesions are the most frequently occurring postoperative complication following abdomino-pelvic surgery. Abdominal and pelvic surgery can lead to peritoneal adhesion formation causing infertility, chronic pelvic pain, and intestinal obstruction. Laparoscopy today is considered the gold standard of care in the treatment of several abdominal pathologies as well as in a wide range of vascular diseases. Laparoscopy has several advantages in comparison to open surgery. These include rapid recovery times, shorter hospitalisation, reduced postoperative pain, as well as cosmetic benefits. The technological improvements in this particular surgical field along with the development of modern techniques and the acquisition of specific laparoscopic skills have allowed for its wider utilization in operations with fully intracorporeal anastomoses. Postoperative adhesions are caused by aberrant peritoneal healing and are the leading cause of postoperative bowel obstruction. The use of anti-adherence barriers is currently being advocated for their prevention. The outcome of the investigation showed adhesion formation inhibition without direct detrimental effects on anastomotic healing. Poor anasto-motic healing can provoke adhesions even in the presence of anti-adhesion barriers. This review gives a short overview on the current evidence on the pathophysiology and prevention of peritoneal adhesions.

  4. Preferentially affected sites of cerebral arteriosclerosis in vascular dementia of Binswanger type. A study of MRI and MR angiography

    International Nuclear Information System (INIS)

    MRI and MR angiography (MRA) were analyzed to evaluate the preferential sites of cerebral arteriosclerosis in 129 normal controls and 27 patients with vascular dementia of Binswanger type (BVD; mean age 75.0 years). Small vessel disease, indicated as advanced high intensity areas on T2-weighted MRI, increased with advancing age, while large vessel sclerosis detected with MRA did not increase after the age of 80 years. Large vessel sclerosis was not always accompanied with advanced high intensity areas. Large vessel sclerosis was found in 12 (44.4%) of 27 patients with BVD, and was as common as that of the controls of the eighth decade. Large vessel sclerosis was frequently seen in the cases suffering from BVD below 70 years of age or with hypertension. In conclusion, patients with BVD develop cerebral arteriosclerosis more preferentially in the small vessels rather than the large vessels especially in aged cases, of which incidence is similar to that of the normal controls over 80 years of age. (author)

  5. 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....

  6. A Partial Intensity Invariant Feature Descriptor for Multimodal Retinal Image Registration

    OpenAIRE

    Chen, Jian; Tian, Jie; Lee, Noah; Zheng, Jian; Smith, R. Theodore; Laine, Andrew F

    2010-01-01

    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 inv...

  7. Endothelium Expression of Bcl-2 Is Essential for Normal and Pathological Ocular Vascularization.

    Directory of Open Access Journals (Sweden)

    Ismail S Zaitoun

    Full Text Available Bcl-2 is an anti-apoptotic protein with important roles in vascular homeostasis and angiogenesis. Mice globally lacking Bcl-2 (Bcl-2 -/- are small in stature and succumb to renal failure shortly after weaning as a result of renal hypoplasia/cystic dysplasia. We have shown that Bcl-2 -/- mice displayed attenuated retinal vascular development and neovascularization. In vitro studies indicated that in addition to modulating apoptosis, Bcl-2 expression also impacts endothelial and epithelial cell adhesion, migration and extracellular matrix production. However, studies delineating the cell autonomous role Bcl-2 expression plays in the endothelium during vascular development, pruning and remodeling, and neovascularization are lacking. Here we generated mice carrying a conditional Bcl-2 allele (Bcl-2Flox/Flox and VE-cadherin-cre (Bcl-2EC mice. Bcl-2EC mice were of normal stature and lifespan and displayed some but not all of the retinal vascular defects previously observed in global Bcl-2 deficient mice. Bcl-2EC mice had decreased numbers of endothelial cells, decreased retinal arteries and premature primary branching of the retinal vasculature, but unlike the global knockout mice, spreading of the retinal superficial vascular layer proceeded normally. Choroidal neovascularization was attenuated in Bcl-2EC mice, although retinal neovascularization accompanying oxygen-induced ischemic retinopathy was not. Thus, Bcl-2 expression in the endothelium plays a significant role during postnatal retinal vascularization, and pathological choroidal but not retinal neovascularization, suggesting vascular bed specific Bcl-2 function in the endothelium.

  8. Endothelium Expression of Bcl-2 Is Essential for Normal and Pathological Ocular Vascularization.

    Science.gov (United States)

    Zaitoun, Ismail S; Johnson, Ryan P; Jamali, Nasim; Almomani, Reem; Wang, Shoujian; Sheibani, Nader; Sorenson, Christine M

    2015-01-01

    Bcl-2 is an anti-apoptotic protein with important roles in vascular homeostasis and angiogenesis. Mice globally lacking Bcl-2 (Bcl-2 -/-) are small in stature and succumb to renal failure shortly after weaning as a result of renal hypoplasia/cystic dysplasia. We have shown that Bcl-2 -/- mice displayed attenuated retinal vascular development and neovascularization. In vitro studies indicated that in addition to modulating apoptosis, Bcl-2 expression also impacts endothelial and epithelial cell adhesion, migration and extracellular matrix production. However, studies delineating the cell autonomous role Bcl-2 expression plays in the endothelium during vascular development, pruning and remodeling, and neovascularization are lacking. Here we generated mice carrying a conditional Bcl-2 allele (Bcl-2Flox/Flox) and VE-cadherin-cre (Bcl-2EC mice). Bcl-2EC mice were of normal stature and lifespan and displayed some but not all of the retinal vascular defects previously observed in global Bcl-2 deficient mice. Bcl-2EC mice had decreased numbers of endothelial cells, decreased retinal arteries and premature primary branching of the retinal vasculature, but unlike the global knockout mice, spreading of the retinal superficial vascular layer proceeded normally. Choroidal neovascularization was attenuated in Bcl-2EC mice, although retinal neovascularization accompanying oxygen-induced ischemic retinopathy was not. Thus, Bcl-2 expression in the endothelium plays a significant role during postnatal retinal vascularization, and pathological choroidal but not retinal neovascularization, suggesting vascular bed specific Bcl-2 function in the endothelium. PMID:26444547

  9. Changes in vascular and transpiration flows affect the seasonal and daily growth of kiwifruit (Actinidia deliciosa) berry

    Science.gov (United States)

    Morandi, Brunella; Manfrini, Luigi; Losciale, Pasquale; Zibordi, Marco; Corelli Grappadelli, Luca

    2010-01-01

    Background and Aims The kiwifruit berry is characterized by an early stage of rapid growth, followed by a relatively long stage of slow increase in size. Vascular and transpiration flows are the main processes through which water and carbon enter/exit the fruit, determining the daily and seasonal changes in fruit size. This work investigates the biophysical mechanisms underpinning the change in fruit growth rate during the season. Methods The daily patterns of phloem, xylem and transpiration in/outflows have been determined at several stages of kiwifruit development, during two seasons. The different flows were quantified by comparing the diurnal patterns of diameter change of fruit, which were then girdled and subsequently detached while measurements continued. The diurnal courses of leaf and stem water potential and of fruit pressure potential were also monitored at different times during the season. Key Results Xylem and transpiration flows were high during the first period of rapid volume growth and sharply decreased with fruit development. Specific phloem import was lower and gradually decreased during the season, whereas it remained constant at whole-fruit level, in accordance with fruit dry matter gain. On a daily basis, transpiration always responded to vapour pressure deficit and contributed to the daily reduction of fruit hydrostatic pressure. Xylem flow was positively related to stem-to-fruit pressure potential gradient during the first but not the last part of the season, when xylem conductivity appeared to be reduced. Conclusions The fruit growth model adopted by this species changes during the season due to anatomical modifications in the fruit features. PMID:20382641

  10. 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

  11. 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.

  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. 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

  14. Macrovaso retiniano congênito: relato de caso Congenital retinal macrovessel: case report

    Directory of Open Access Journals (Sweden)

    Rodrigo Tavares Schueler

    2005-06-01

    Full Text Available O macrovaso retiniano congênito é rara anomalia vascular em que um vaso grande e suas tributárias cruzam a mácula. Descrevemos um caso de macrovaso retiniano em paciente com queixa de baixa acuidade visual.Congenital retinal macrovessel is a rare vascular anomaly in which a large vessel and its tributaries cross the macula. We describe a case of retinal macrovessel in a patient complaining of decrease in visual acuity.

  15. Prepapillary Vascular Loops Complicated by Suspected Macroaneurysm Rupture

    Directory of Open Access Journals (Sweden)

    Kei Akaiwa

    2014-01-01

    Full Text Available We present a case of prepapillary vascular loops complicated by a suspected macroaneurysm rupture which was treated with intravitreal bevacizumab (IVB. A 62-year-old woman presented with decreased vision and myodesopsia in her left eye. Her best-corrected visual acuity (BCVA was 0.6 in the left eye. Fundus examination disclosed an elevated, round, and reddish lesion, retinal hemorrhage at the superior aspect of the optic disc, retinal opacification along the superior branch retinal artery, and a small vitreous hemorrhage. Optical coherence tomography showed a serous retinal detachment, and indocyanine green angiography demonstrated prepapillary vascular loops and a hypofluorescent area with hyperfluorescent margins. These findings suggested the presence of a macroaneurysm. No filling of the dye in the aneurysm-like dilatation suggested a blockage of the lumen with a thrombus which might be associated with a branch retinal artery occlusion (BRAO. A diagnosis of prepapillary vascular loops complicated by a suspected macroaneurysm rupture and BRAO was made. Because of a persistent serous retinal detachment, IVB was performed. One month later, the BCVA improved to 1.0. Fundus examination disclosed an organized yellowish-white macroaneurysm and resolution of the serous retinal detachment. We recommend careful monitoring of patients with prepapillary vascular loops because of complications such as macroaneurysm rupture and BRAO.

  16. 孕期酒精暴露对子鼠视网膜双极细胞和水平细胞发育的影响%Prenatal alcohol exposure affects development of retinal bipolar and horizontal cells in mice

    Institute of Scientific and Technical Information of China (English)

    刘曦; 王永毅; 姚焕玲; 赵博; 于亚东; 胡馨; 邓锦波

    2012-01-01

    Objective To investigate effects of alcohol exposure during pregnancy on retinal bipolar and horizontal cells in filial mice. Methods The animal model of prenatal alcohol exposure was made. The development of bipolar cells and horizontal cells at prenatal days 7, 14 and 30 was investigated with immunofluorescent labeling and Dil scattering techniques. Results In all age groups, the density of the bipolar cells was significantly lower in the experiment groups than in the control groups. The dendritic field and the number of branches of horizontal cells were significantly lower in the experimental group than in the control group (P < 0. 01). Conclusion Alcohol exposure during pregnancy affects development of retinal bipolar and horizontal cells in mice.%目的 探讨孕期酒精暴露对子鼠视网膜双极细胞和水平细胞发育的影响.方法 建立孕期酒精暴露小鼠模型;采用免疫荧光染色和DiI散射技术,观察酒精对日龄7d(P7)、P14和P30子鼠视网膜双极细胞和水平细胞的影响.结果 各年龄组中,酒精组视网膜双极细胞的密度明显低于对照组,且呈剂量依赖性和长时程效应;水平细胞的树突野及树突数也明显低于对照组,呈剂量依赖性和长时程效应(P<0.01).结论 孕期酒精暴露影响子鼠视网膜双极细胞和水平细胞的发育.

  17. Modern retinal laser therapy

    OpenAIRE

    Kozak, Igor; Luttrull, Jeffrey K.

    2014-01-01

    Medicinal lasers are a standard source of light to produce retinal tissue photocoagulation to treat retinovascular disease. The Diabetic Retinopathy Study and the Early Treatment Diabetic Retinopathy Study were large randomized clinical trials that have shown beneficial effect of retinal laser photocoagulation in diabetic retinopathy and have dictated the standard of care for decades. However, current treatment protocols undergo modifications. Types of lasers used in treatment of retinal dise...

  18. Thrombolysis in vascular surgery

    OpenAIRE

    Smith, Linn

    2015-01-01

    Background and aims: Thrombolysis is in common use in the treatment of acute forms of vascular disease. It may be used both systemically and locally, in the latter case through an endovascular approach, socalled catheter-directed thrombolysis. The aims of this thesis were to investigate how thrombolysis affects performance-related outcomes pertaining to vascular patency after thrombolysis, and how it affects patient safety and the development of complications. Metho...

  19. The retinal ciliopathies.

    Science.gov (United States)

    Adams, N A; Awadein, Ahmed; Toma, Hassanain S

    2007-09-01

    While the functions of many of the proteins located in or associated with the photoreceptor cilia are poorly understood, disruption of the function of these proteins may result in a wide variety of phenotypes ranging from isolated retinal degeneration to more pleiotropic phenotypes. Systemic findings include neurosensory hearing loss, developmental delay, situs-inversus, infertility, disorders of limb and digit development, obesity, kidney disease, liver disease, and respiratory disease. The concept of "retinal ciliopathies" brings to attention the importance of further molecular analysis of this organelle as well as provides a potential common target for therapies for these disorders. The retinal ciliopathies include retinitis pigmentosa, macular degeneration, cone-dystrophy, cone-rod dystrophy, Leber congenital amaurosis, as well as retinal degenerations associated with Usher syndrome, primary ciliary dyskinesia, Senior-Loken syndrome, Joubert syndrome, Bardet-Biedl syndrome, Laurence-Moon syndrome, McKusick-Kaufman syndrome, and Biemond syndrome. Mutations for these disorders have been found in retinitis pigmentosa-1 (RP1), retinitis pigmentosa GTPase regulator (RPGR), retinitis pigmentosa GTPase regulator interacting protein (RPGR-IP), as well as the Usher, Bardet-Biedl, and nephronophthisis genes. Other systemic disorders associated with retinal degenerations that may also involve ciliary abnormalities include: Alstrom, Edwards-Sethi, Ellis-van Creveld, Jeune, Meckel-Gruber, Orofaciodigital Type 9, and Gurrieri syndromes. Understanding these conditions as ciliopathies may help the ophthalmologist to recognize associations between seemingly unrelated diseases and have a high degree of suspicion that a systemic finding may be present. PMID:17896309

  20. Overexpression of retinal degeneration slow (RDS protein adversely affects rods in the rd7 model of enhanced S-cone syndrome.

    Directory of Open Access Journals (Sweden)

    Dibyendu Chakraborty

    Full Text Available The nuclear receptor NR2E3 promotes expression of rod photoreceptor genes while repressing cone genes. Mice lacking NR2E3 (Nr2e3(rd7/rd7 referred to here as rd7 are a model for enhanced S-cone syndrome, a disease associated with increased sensitivity to blue light and night blindness. Rd7 retinas have reduced levels of the outer segment (OS structural protein retinal degeneration slow (RDS. We test the hypothesis that increasing RDS levels would improve the Rd7 phenotype. Transgenic mice over-expressing normal mouse peripherin/RDS (NMP in rods and cones were crossed onto the rd7 background. Disease phenotypes were assessed in NMP/rd7 eyes and compared to wild-type (WT and rd7 eyes at postnatal day 30. NMP/rd7 retinas expressed total RDS (transgenic and endogenous message at WT levels, and NMP protein was correctly localized to the OS. NMP/rd7 retinas have shorter OSs compared to rd7 and WT and significantly reduced number of rosettes. NMP/rd7 mice also exhibited significant deficits in scotopic ERG amplitudes compared to rd7 while photopic amplitudes remained unaffected. Protein levels of rhodopsin, RDS, and the RDS homologue ROM-1 were significantly reduced in the NMP/rd7 retinas compared to rd7. We show that correcting the levels of RDS gene expression does not improve the phenotype of the rd7 suggesting that RDS deficiency is not responsible for the defect in this model. We suggest that the specific rod defect in the NMP/rd7 is likely associated with ongoing problems in the rd7 that are related to the expression of cone genes in rod cells, a characteristic of the model.

  1. Myocardial performance index is sensitive to changes in cardiac contractility, but is also affected by vascular load condition.

    Science.gov (United States)

    Uemura, Kazunori; Kawada, Toru; Zheng, Can; Li, Meihua; Shishido, Toshiaki; Sugimachi, Masaru

    2013-01-01

    Myocardial performance index (MPI), or Tei index, is measured by Doppler echocardiography in clinical practice. MPI has been shown to be useful in evaluating left ventricular (LV) performance and predicting prognosis in cardiac patients. However, the effects of LV load and contractile states on MPI remain to be thoroughly investigated. In 14 anesthetized dogs, we obtained LV pressure-volume relationship with use of sonomicrometry and catheter-tip manometry. MPI was determined from the time derivative of LV volume and pressure. LV end-systolic pressure-volume ratio (Ees'), effective arterial elastance (Ea) and LV end-diastolic volume (Ved) were used as indices of LV contractility, afterload and preload, respectively. Hemodynamic conditions were varied over wide ranges [heart rate (HR), 66-192 bpm; mean arterial pressure, 71-177 mmHg] by infusing cardiovascular agents, by inducing ischemic heart failure and by electrical atrial pacing. Multiple linear regression analysis of pooled data (66 data sets) indicated that MPI (0.6-1.8) significantly correlated with Ees' [1.5-17.5 mmHg · ml(-1), pVed (11-100 ml, p0.1). Theoretical analysis also indicated that MPI decreases following the increases in LV contractility and in preload, while it increases in response to an increase in LV afterload. We conclude that MPI sensitively detects changes in LV contractility. However, MPI is also affected by changes in LV afterload and preload. PMID:24109782

  2. Arginase 2 deficiency reduces hyperoxia-mediated retinal neurodegeneration through the regulation of polyamine metabolism.

    Science.gov (United States)

    Narayanan, S P; Xu, Z; Putluri, N; Sreekumar, A; Lemtalsi, T; Caldwell, R W; Caldwell, R B

    2014-01-01

    Hyperoxia treatment has been known to induce neuronal and glial death in the developing central nervous system. Retinopathy of prematurity (ROP) is a devastating disease in premature infants and a major cause of childhood vision impairment. Studies indicate that, in addition to vascular injury, retinal neurons are also affected in ROP. Using an oxygen-induced retinopathy (OIR) mouse model for ROP, we have previously shown that deletion of the arginase 2 (A2) significantly reduced neuro-glial injury and improved retinal function. In the current study, we investigated the mechanism of A2 deficiency-mediated neuroprotection in the OIR retina. Hyperoxia treatment has been known to induce neuronal death in neonates. During the hyperoxia phase of OIR, a significant increase in the number of apoptotic cells was observed in the wild-type (WT) OIR retina compared with A2-deficient OIR. Mass spectrometric analysis showed alterations in polyamine metabolism in WT OIR retina. Further, increased expression level of spermine oxidase was observed in WT OIR retina, suggesting increased oxidation of polyamines in OIR retina. These changes were minimal in A2-deficient OIR retina. Treatment using the polyamine oxidase inhibitor, N, N'-bis (2, 3-butadienyl)-1, 4-butanediamine dihydrochloride, significantly improved neuronal survival during OIR treatment. Our data suggest that retinal arginase is involved in the hyperoxia-induced neuronal degeneration in the OIR model, through the regulation of polyamine metabolism. PMID:24556690

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

    Directory of Open Access Journals (Sweden)

    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

  4. Functional and structural modifications during retinal degeneration in the rd10 mouse

    OpenAIRE

    Barhoum, Rima; Martínez Navarrete, Gema Concepción; Corrochano Sánchez, Silvia; Germain Martínez, Francisco; Fernández Sánchez, Laura; Rosa Cano, Enrique J. de la; Villa Polo, Pedro de la; Cuenca Navarro, Nicolás

    2008-01-01

    Mouse models of retinal degeneration are useful tools to study therapeutic approaches for patients affected by hereditary retinal dystrophies. We have studied degener- ation in the rd10 mice both by immunocytochemistry and TUNEL-labeling of retinal cells, and through electrophysiological recordings. The cell degeneration in the retina of rd10 mice produced appreciable morphological changes in rod and cone cells by P20. Retinal cell death is clearly observed in the central retina and it peaked...

  5. Human identification system based on the detection of optical Disc Ring in retinal images

    OpenAIRE

    Chihaoui, Takwa; Kachouri, Rostom; Jlassi, Hejer; Akil, Mohamed; Hamrouni, Kamel

    2015-01-01

    Retinal identification is being studied as a hot research topic in the biometric field. Many factors such as the poor quality of retinal images and the huge execution time can seriously affect the performance of the retinal identification systems. In this context, in order to compromise the quality and the processing time, this paper presents a human identification system based on a new preprocessing method of retinal images that we call optical Disc Ring detection method. The proposed ODR me...

  6. Compliance of the aorta in two diseases affecting vascular elasticity, familial hypercholesterolemia and diabetes: a MRI study

    Directory of Open Access Journals (Sweden)

    Sami Soljanlahti

    2008-08-01

    Full Text Available Sami Soljanlahti1, Taina Autti1, Laura Hyttinen2, Alpo F Vuorio3, Pekka Keto1, Kirsi Lauerma11Helsinki Medical Imaging Center, Helsinki University Central Hospital, Helsinki, Finland; 2Department of Internal Medicine, North Karelia Central Hospital, Joensuu, Finland; 3Division of Internal Medicine, Department of Medicine, University of Helsinki, Helsinki, FinlandAbstract: Arterial elasticity changes in familial hypercholesterolemia (FH and diabetes mellitus (DM with different but overlapping mechanisms. We compared aortic elasticity between 19 FH patients with the same mutation, 18 type 2 DM patients, and 30 controls, all aged 48 to 64. They underwent aortic magnetic resonance imaging, risk-factor assessment, and carotid and femoral ultrasound measurements. All patients were on adequate cardiovascular medication including statins and had established coronary heart disease (CHD. FH patients had longer-duration CHD (13.3 ± 7.7 years than did DM patients (5.0 ± 3.1. Aortic compliance in the descending thoracic (DM 0.38 ± 0.14 vs control 0.53 ± 0.19, P = 0.032 and abdominal aorta (DM 0.45 ± 0.20 vs control 0.66 ± 0.25, P = 0.011 was lower in DM patients than in controls, whereas no significant difference existed between FH patients and controls. Carotid and femoral intima-media thickness was greater in FH and DM patients than in controls with no difference between patient groups. Carotid or femoral plaques appeared in 15 (79% FH and in 10 (56% DM patients. One control had a femoral plaque. Five FH patients showed stenosis, occlusion or both in carotid arteries. In our opinion, DM patients’ lower compliance reflect mainly arterial media affecting arteriosclerosis, while FH patients’ plaque status and longer duration of CHD suggest more advanced atherosclerosis. The FH patients may therefore be at increased risk for atherothrombotic events. However, due to small patient material, larger confirmatory studies are needed.Keywords: MRI

  7. Automated retinal image quality assessment on the UK Biobank dataset for epidemiological studies.

    Science.gov (United States)

    Welikala, R A; Fraz, M M; Foster, P J; Whincup, P H; Rudnicka, A R; Owen, C G; Strachan, D P; Barman, S A

    2016-04-01

    Morphological changes in the retinal vascular network are associated with future risk of many systemic and vascular diseases. However, uncertainty over the presence and nature of some of these associations exists. Analysis of data from large population based studies will help to resolve these uncertainties. The QUARTZ (QUantitative Analysis of Retinal vessel Topology and siZe) retinal image analysis system allows automated processing of large numbers of retinal images. However, an image quality assessment module is needed to achieve full automation. In this paper, we propose such an algorithm, which uses the segmented vessel map to determine the suitability of retinal images for use in the creation of vessel morphometric data suitable for epidemiological studies. This includes an effective 3-dimensional feature set and support vector machine classification. A random subset of 800 retinal images from UK Biobank (a large prospective study of 500,000 middle aged adults; where 68,151 underwent retinal imaging) was used to examine the performance of the image quality algorithm. The algorithm achieved a sensitivity of 95.33% and a specificity of 91.13% for the detection of inadequate images. The strong performance of this image quality algorithm will make rapid automated analysis of vascular morphometry feasible on the entire UK Biobank dataset (and other large retinal datasets), with minimal operator involvement, and at low cost. PMID:26894596

  8. 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.

  9. A Case of Retinal Tear Associated with Use of Sorafenib

    OpenAIRE

    KellyM.Gaertner; OsamaRahma; StephenH.Caldwell

    2014-01-01

    Inhibition of angiogenesis is a target in the treatment of a variety of malignancies. Sorafenib is an oral inhibitor of multiple tyrosine kinases involved in tumor angiogenesis. A related case of ophthalmologic toxicity has been reported with another vascular endothelial growth factor receptor inhibitor, sunitinib. We report the first case of retinal tear possibly associated with sorafenib.

  10. Heritability of retinal vessel diameters and blood pressure

    DEFF Research Database (Denmark)

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

    2006-01-01

    , aged 20 to 46 years, interpolated diameter estimates for the central retinal artery (CRAE), the central retinal vein (CRVE), and the artery-to-vein diameter ratio (AVR) were assessed by analysis of digital gray-scale fundus photographs of right eyes. RESULTS: The heritability was 70% (95% CI: 54...... for CRVE, and 0.67 +/- 0.05 microm for AVR. No significant influence on artery or vein diameters was found for gender, smoking, body mass index (BMI), total cholesterol, fasting blood glucose, or 2-hour oral glucose tolerance test values. CONCLUSIONS: In healthy young adults with normal blood pressure...... 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 and the...

  11. 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

  12. 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.

  13. A case of CRB1-negative Coats-like retinitis pigmentosa.

    Science.gov (United States)

    Sarao, Valentina; Veritti, Daniele; Prosperi, Raffaele; Pignatto, Silvia; Lanzetta, Paolo

    2013-08-01

    Retinitis pigmentosa is a heterogeneous group of ocular diseases that causes progressive degeneration of the photoreceptor cells mainly affecting the rods of the peripheral retina. The association between retinitis pigmentosa and exudative retinopathy was first described in 1956 and has been called "Coats-like retinitis pigmentosa." Mutations in the Crumbs homolog 1 (CRB1) gene have been reported as a risk factor for developing Coats-like changes in patients with autosomal recessive retinitis pigmentosa. We report the case of a 15-year-old girl affected by CRB1 gene-negative retinitis pigmentosa and Coats-like exudative vasculopathy who was successfully treated with laser photocoagulation. PMID:23871396

  14. Laser photocoagulation for retinal vein occlusion

    Directory of Open Access Journals (Sweden)

    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. 

  15. Repetitive magnetic stimulation improves retinal function in a rat model of retinal dystrophy

    Science.gov (United States)

    Rotenstreich, Ygal; Tzameret, Adi; Levi, Nir; Kalish, Sapir; Sher, Ifat; Zangen, Avraham; Belkin, Michael

    2014-02-01

    Vision incapacitation and blindness associated with retinal dystrophies affect millions of people worldwide. Retinal degeneration is characterized by photoreceptor cell death and concomitant remodeling of remaining retinal cells. Repetitive Magnetic Stimulation (RMS) is a non-invasive technique that creates alternating magnetic fields by brief electric currents transmitted through an insulated coil. These magnetic field generate action potentials in neurons, and modulate the expression of neurotransmitter receptors, growth factors and transcription factors which mediate plasticity. This technology has been proven effective and safe in various psychiatric disorders. Here we determined the effect of RMS on retinal function in Royal College of Surgeons (RCS) rats, a model for retinal dystrophy. Four week-old RCS and control Spargue Dawley (SD) rats received sham or RMS treatment over the right eye (12 sessions on 4 weeks). RMS treatment at intensity of at 40% of the maximal output of a Rapid2 stimulator significantly increased the electroretinogram (ERG) b-wave responses by up to 6- or 10-fold in the left and right eye respectively, 3-5 weeks following end of treatment. RMS treatment at intensity of 25% of the maximal output did not significant effect b-wave responses following end of treatment with no adverse effect on ERG response or retinal structure of SD rats. Our findings suggest that RMS treatment induces delayed improvement of retinal functions and may induce plasticity in the retinal tissue. Furthermore, this non-invasive treatment may possibly be used in the future as a primary or adjuvant treatment for retinal dystrophy.

  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. Risk Factors for Central and Branch Retinal Vein Occlusion: A Meta-Analysis of Published Clinical Data

    OpenAIRE

    Kolar, Petr

    2014-01-01

    Retinal vein occlusion (RVO) is a major cause of vision loss. Of the two main types of RVO, branch retinal vein occlusion (BRVO) is 4 to 6 times more prevalent than central retinal vein occlusion (CRVO). A basic risk factor for RVO is advancing age. Further risk factors include systemic conditions like hypertension, arteriosclerosis, diabetes mellitus, hyperlipidemia, vascular cerebral stroke, blood hyperviscosity, and thrombophilia. A strong risk factor for RVO is the metabolic syndrome (hyp...

  18. Changes in retinal vessels related to varicocele: a pilot investigation.

    Science.gov (United States)

    Coşkun, M; Ilhan, N; Elbeyli, A; Rifaioğlu, M M; Inci, M; Davran, R; Tuzcu, E A; Yarbağ, A; Davarci, M; Gökçe, A

    2016-06-01

    The aim of this study was to investigate whether retinal vasculature changes had occurred (retinal artery diameter, retinal vein diameter and artery/vein ratio) in patients with varicocele. This pilot study included 50 healthy subjects with any eye disease apart from slight refractive errors and 55 patients with varicocele. Retinal arteriolar and venular diameters were measured and summarised as central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent (CRVE). Retinal microvascular diameters and the arteriolar-to-venular ratio (AVR) were assessed with a digital retinal camera. All measurements and calculations were performed using a computer-based program. The mean CRAE value was 151.8 ± 3.6 μm in the study group and 150.4 ± 4.5 μm in the control group. Mean CRVE value was 209.4 ± 5.9 μm in the study group and 200.1 ± 8.7 μm in the control group. AVR was found 0.72 ± 0.02 in the study group and 0.75 ± 0.03 in the control group. There were significant differences between groups in terms of CRVE and AVR. There were no significant differences between groups in terms of CRAE. The results of this study showed that the patients with varicocele showed significant changes on retinal vascular diameter. PMID:26314401

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

    Science.gov (United States)

    de Hoz, Rosa; Salazar, Juan J; Ramírez, Ana I; Rojas, Blanca; Gallego, Beatriz I.; Triviño, Alberto; Tejerina, Teresa

    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. PMID:27144842

  20. 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

    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......-promoting factor. The activation tagging of VAS only resulted in a specific increase in phloem (pro)cambial and pericycle cells. We conclude that activation tagging of LEP and VAS results in additive phenotypes. Insertional mutants for LEP and VAS display wild-type vascular development, indicating the relevance of...... activation tagging for functional analysis of novel genes involved in plant development....

  1. [Acute retinal necrosis].

    Science.gov (United States)

    Lucke, K; Reinking, U; el-Hifnawi, E; Dennin, R H; Laqua, H

    1988-12-01

    The authors report on three patients with acute retinal necrosis who were treated with the virostatic agent Acyclovir and who underwent vitreoretinal surgery with silicone oil filling for total retinal detachment. In two eyes the retina was reattached, but useful vision was only preserved in one patient. Titers from blood and the vitreous, as well as microscopic findings in retinal biopsies, support the view that the necrosis is caused by a herpes simplex virus infection. After therapy with Acyclovir was instituted no further progression on the necrosis was observed. However, the development of retinal detachment could not be prevented. Early diagnosis and antiviral therapy are essential to improve the otherwise poor prognosis in this rare syndrome. PMID:3221657

  2. Retinal laser optical aids

    Directory of Open Access Journals (Sweden)

    Das Traprasad

    1991-01-01

    Full Text Available Knowledge of optics, comparative magnification and working field of view is essential for rational use of ophthalmoscopic contact lenses for retinal photocoagulation. The three commonly used contact lenses are described and compared.

  3. Retinal Tears and Detachments

    Science.gov (United States)

    ... does not cause retinal damage. However, inflammation or myopia (nearsightedness) may cause the vitreous to pull away ... repaired? If your retina is only torn, prompt treatment may prevent detachment. Your eye surgeon will discuss ...

  4. Advances in retinal ganglion cell imaging.

    Science.gov (United States)

    Balendra, S I; Normando, E M; Bloom, P A; Cordeiro, M F

    2015-10-01

    Glaucoma is one of the leading causes of blindness worldwide and will affect 79.6 million people worldwide by 2020. It is caused by the progressive loss of retinal ganglion cells (RGCs), predominantly via apoptosis, within the retinal nerve fibre layer and the corresponding loss of axons of the optic nerve head. One of its most devastating features is its late diagnosis and the resulting irreversible visual loss that is often predictable. Current diagnostic tools require significant RGC or functional visual field loss before the threshold for detection of glaucoma may be reached. To propel the efficacy of therapeutics in glaucoma, an earlier diagnostic tool is required. Recent advances in retinal imaging, including optical coherence tomography, confocal scanning laser ophthalmoscopy, and adaptive optics, have propelled both glaucoma research and clinical diagnostics and therapeutics. However, an ideal imaging technique to diagnose and monitor glaucoma would image RGCs non-invasively with high specificity and sensitivity in vivo. It may confirm the presence of healthy RGCs, such as in transgenic models or retrograde labelling, or detect subtle changes in the number of unhealthy or apoptotic RGCs, such as detection of apoptosing retinal cells (DARC). Although many of these advances have not yet been introduced to the clinical arena, their successes in animal studies are enthralling. This review will illustrate the challenges of imaging RGCs, the main retinal imaging modalities, the in vivo techniques to augment these as specific RGC-imaging tools and their potential for translation to the glaucoma clinic. PMID:26293138

  5. 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

  6. [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. PMID:27011029

  7. Intraocular retinal prosthesis.

    OpenAIRE

    Humayun, M. S.

    2001-01-01

    PURPOSE: An electronic implant that can bypass the damaged photoreceptors and electrically stimulate the remaining retinal neurons to restore useful vision has been proposed. A number of key questions remain to make this approach feasible. The goal of this thesis is to address the following 2 specific null hypotheses: (1) Stimulus parameters make no difference in the electrically elicited retinal responses. (2) Just as we have millions of photoreceptors, so it will take a device that can gene...

  8. 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

  9. 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.

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

    Science.gov (United States)

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

    2016-01-01

    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. PMID:27511757

  11. 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...

  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. Hypoxia-ischemia and retinal ganglion cell damage

    Directory of Open Access Journals (Sweden)

    Charanjit Kaur

    2008-08-01

    Full Text Available Charanjit Kaur1, Wallace S Foulds2, Eng-Ang Ling11Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; 2Singapore Eye Research Institute, SingaporeAbstract: Retinal hypoxia is the potentially blinding mechanism underlying a number of sight-threatening disorders including central retinal artery occlusion, ischemic central retinal vein thrombosis, complications of diabetic eye disease and some types of glaucoma. Hypoxia is implicated in loss of retinal ganglion cells (RGCs occurring in such conditions. RGC death occurs by apoptosis or necrosis. Hypoxia-ischemia induces the expression of hypoxia inducible factor-1α and its target genes such as vascular endothelial growth factor (VEGF and nitric oxide synthase (NOS. Increased production of VEGF results in disruption of the blood retinal barrier leading to retinal edema. Enhanced expression of NOS results in increased production of nitric oxide which may be toxic to the cells resulting in their death. Excess glutamate release in hypoxic-ischemic conditions causes excitotoxic damage to the RGCs through activation of ionotropic and metabotropic glutamate receptors. Activation of glutamate receptors is thought to initiate damage in the retina by a cascade of biochemical effects such as neuronal NOS activation and increase in intracellular Ca2+ which has been described as a major contributing factor to RGC loss. Excess production of proinflammatory cytokines also mediates cell damage. Besides the above, free-radicals generated in hypoxic-ischemic conditions result in RGC loss because of an imbalance between antioxidant- and oxidant-generating systems. Although many advances have been made in understanding the mediators and mechanisms of injury, strategies to improve the damage are lacking. Measures to prevent neuronal injury have to be developed.Keywords: retinal hypoxia, retinal ganglion cells, glutamate receptors, neuronal injury, retina

  14. Retinal oxygen extraction in humans

    OpenAIRE

    René M. Werkmeister; Doreen Schmidl; Gerold Aschinger; Veronika Doblhoff-Dier; Stefan Palkovits; Magdalena Wirth; Gerhard Garhöfer; Linsenmeier, Robert A.; Rainer A. Leitgeb; Leopold Schmetterer

    2015-01-01

    Adequate function of the retina is dependent on proper oxygen supply. In humans, the inner retina is oxygenated via the retinal circulation. We present a method to calculate total retinal oxygen extraction based on measurement of total retinal blood flow using dual-beam bidirectional Doppler optical coherence tomography and measurement of oxygen saturation by spectrophotometry. These measurements were done on 8 healthy subjects while breathing ambient room air and 100% oxygen. Total retinal b...

  15. A novel registration method for retinal images based on local features

    OpenAIRE

    Chen, Jian; R Theodore Smith; Tian, Jie; Laine, Andrew F

    2008-01-01

    Sometimes it is very hard to automatically detect the bifurcations of vascular network in retinal images so that the general feature based registration methods will fail to register two images. In order to solve this problem, we developed a novel local feature based retinal image registration method. We first detect the corner points instead of bifurcations since corner points are sufficient and uniformly distributed in the overlaps. Second, a novel highly distinctive local feature is extract...

  16. 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.

  17. 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.

  18. Retinal vein occlusion in Benin City, Nigeria

    Directory of Open Access Journals (Sweden)

    Odarosa M Uhumwangho

    2016-01-01

    Full Text Available Background: Retinal vein occlusion (RVO is the most common occlusive retinal vascular disorder and results in varying degrees of visual loss. Aim: To determine the pattern of presentation, risk factors, and treatment outcomes in a group of patients with RVO seen in a tertiary hospital in Nigeria. Materials and Methods: Medical records of patients who presented to the University of Benin Teaching Hospital, Benin City, Nigeria in whom a diagnosis of RVO was made over a 5 years period were reviewed. Data obtained were analyzed with the GraphPad Instat Software, Inc. version V2.05a program, San Diego, Califonia and a P < 0.05 considered significant. Results: There were 20 patients made of 14 (70.0% males and 6 (30.0% females with a mean age of 62.7 ± 10.4 years. There were 15 (68.2% eyes with central RVO, 3 (13.6% eyes with branch RVO, and 4 (18.2% eyes with hemi RVO. Bilateral involvement occurred in 2 (10.0% patients. Risk factors included hypertension 14 (70.0%, diabetes mellitus 9 (45.0%, and glaucoma 5 (22.7%. Multiple risk factors were present in 14 (70.0% patients. Complications included macula edema 15 (68.2%, retinal neovascularization 5 (22.7%, neovascular glaucoma 3 (13.6%, and vitreous hemorrhage 2 (9.1%. Eyes which had definitive treatment with intravitreal antivascular endothelial growth factors and laser photocoagulation for macula edema and retinal neovascularization, respectively, had better visual acuity compared to eyes which did not receive these treatment, P = 0.002. Conclusion: The incidence and visual loss that occurs from RVO can be reduced by modifying known risk factors and early institution of appropriate therapy for complications that occur.

  19. Retinal Ganglion Cell Dendritic Atrophy in DBA/2J Glaucoma

    OpenAIRE

    Williams, Pete A.; Howell, Gareth R.; Barbay, Jessica M.; Braine, Catherine E.; Sousa, Gregory L.; John, Simon W. M.; Morgan, James E.

    2013-01-01

    Glaucoma is a complex disease affecting an estimated 70 million people worldwide, characterised by the progressive degeneration of retinal ganglion cells and accompanying visual field loss. The common site of damage to retinal ganglion cells is thought to be at the optic nerve head, however evidence from other optic neuropathies and neurodegenerative disorders suggests that dendritic structures undergo a prolonged period of atrophy that may accompany or even precede soma loss and neuronal cel...

  20. Good Epidemiologic Practice in Retinitis Pigmentosa: From Phenotyping to Biobanking

    OpenAIRE

    Chizzolini, Marzio; Galan, Alessandro; Milan, Elisabeth; Sebastiani, Adolfo; Costagliola, Ciro; Parmeggiani, Francesco

    2011-01-01

    Inherited retinal dystrophies, such as retinitis pigmentosa (RP), include a group of relatively rare hereditary diseases caused by mutations in genes that code for proteins involved in the maintenance and function of the photoreceptor cells (cones and rods). The different forms of RP consist of progressive neurodegenerative disorders which are generally related to various and severe limitations of visual performances. In the course of typical RP (rod-cone dystrophy), the affected individuals ...

  1. Risk factor profile in retinal detachment

    OpenAIRE

    Azad Raj; Nayak B; Sharma Y; Tiwari Hem; Khosla P

    1988-01-01

    150 cases of retinal detachment comprising 50 patients each of bilateral retinal detachment, unilateral retinal detachment without any retinal lesions in the fellow eve and unilateral retinal detachment with retinal lesions in the fellow eye were studied and the various associated risk factors were statistically analysed. The findings are discussed in relation to their aetiological and prognostic significance in the different types of retinal detachment. Based on these observations certain gu...

  2. Vascular MR

    International Nuclear Information System (INIS)

    This project investigates cardiac gated gradient echo pulses sequences for vascular MR imaging. These pulse sequences have been used to acquire and display MR projection angiograms. The authors have applied these methods in two distinct populations of patients for evaluation and comparison with standard angiography. Twenty patients with abdominal aortic aneurysms, and 35 patients with aortoiliac atherosclerotic disease or peripheral vascular disease were investigated using this method and the results are presented

  3. Vascular Dementia

    OpenAIRE

    Maria Alekseyevna Cherdak; O. V. Uspenskaya

    2015-01-01

    Vascular dementia is one of the most common causes of dementia after Alzheimer's disease, causing around 15% of cases. However, unlike Alzheimer's disease, there are no licensed treatments for vascular dementia. Progress in the specialty has been difficult because of uncertainties over disease classification and diagnostic criteria, controversy over the exact nature of the relation between cerebrovascular pathology and cognitive impairment, and the paucity of identifiable tractable treatment ...

  4. Alterations to retinal architecture prior to photoreceptor loss in a mouse model of retinitis pigmentosa.

    Science.gov (United States)

    Roche, Sarah L; Wyse-Jackson, Alice C; Byrne, Ashleigh M; Ruiz-Lopez, Ana M; Cotter, Thomas G

    2016-01-01

    Mouse models of retinitis pigmentosa (RP) are essential tools in the pursuit to understand fully what cell types and processes underlie the degeneration observed in RP. Knowledge of these processes is required if we are to develop successful therapies to treat this currently incurable disease. We have used the rd10 mouse model of RP to study retinal morphology prior to photoreceptor loss, using immunohistochemistry and confocal microscopy on cryosections, since little is known about how the mutation affects the retina during this period. We report novel findings that the mutation in the rd10 mouse results in retinal abnormalities earlier than was previously thought. Defects in rod and cone outer segments, bipolar cells, amacrine cells and photoreceptor synapses were apparent in the retina during early stages of postnatal retinal development and prior to the loss of photoreceptors. Additionally, we observed a dramatic response of glial cells during this period. Microglia responded as early as postnatal day (P) 5; ?13 days before any photoreceptor loss is detected with Müller glia and astrocytes exhibiting changes from P10 and P15 respectively. Overall, these findings present pathological aspects to the postnatal development of the rd10 retina, contributing significantly to our understanding of disease onset and progression in the rd10 mouse and provide a valuable resource for the study of retinal dystrophies. PMID:27160072

  5. 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.

  6. 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.

  7. Activation of retinal microglia rather than microglial cell density correlates with retinal neovascularization in the mouse model of oxygen-induced retinopathy

    Directory of Open Access Journals (Sweden)

    Martin Gottfried

    2011-09-01

    Full Text Available Abstract Background Retinal neovascularization has been intensively investigated in the mouse model of oxygen-induced retinopathy (OIR. Here, we studied the contribution of microglial cells to vascular regression during the hyperoxic phase and to retinal neovascularization during the hypoxic phase. Methods Mice expressing green fluorescent protein (GFP under the Cx3cr1 promoter labeling microglial cells were kept in 75% oxygen from postnatal day 7 (P7 to P12. Microglial cell density was quantified at different time points and at different retinal positions in retinal flat mounts. Microglial activation was determined by the switch from ramified to amoeboid cell morphology which correlated with the switch from lectin negative to lectin positive staining of GFP positive cells. Results Microglial cell density was constant in the peripheral region of the retina. In the deep vascular layer of the central region, however, it declined 14 fold from P12 to P14 and recovered afterwards. Activated microglial cells were found in the superficial layer of the central avascular zone from P8 to P12 and from P16 to P18. In addition, hyalocytes were found in the vitreal layer in the central region and their cell density decreased over time. Conclusion Density of microglial cells does not correlate with vascular obliteration or revascularization. But the time course of the activation of microglia indicates that they may be involved in retinal neovascularization during the hypoxic phase.

  8. Retinal tolerance to dyes

    OpenAIRE

    Lüke, C; Lüke, M; Dietlein, T S; Hueber, A; Jordan, J; Sickel, W.; Kirchhof, B

    2005-01-01

    Background: Dye solutions for intraoperative staining of epiretinal membranes and the internal limiting membrane improve the visualisation of these thin structures and facilitate their removal. In the present study the authors investigated the effects of indocyanine green 0.05%, trypan blue 0.15%, and patent blue 0.48% on bovine retinal function.

  9. Retinal artery occlusion

    Science.gov (United States)

    ... artery occlusion; Branch retinal artery occlusion; CRAO; BRAO Images Retina References Sanborn GE, Magargal LE. Arterial obstructive disease ... A.M. Editorial team. Related MedlinePlus Health Topics ... audit to verify that A.D.A.M. follows rigorous standards of quality and accountability. A.D.A.M. is among ...

  10. Radiation Retinopathy Is Treatable With Anti-Vascular Endothelial Growth Factor Bevacizumab (Avastin)

    International Nuclear Information System (INIS)

    Purpose: To report on bevacizumab treatment for radiation retinopathy affecting the macula. Patients and Methods: Twenty-one patients with radiation retinopathy (edema, hemorrhages, capillary dropout, and neovascularization) and a subjective or objective loss of vision were treated. Treatment involved intravitreal injection of bevacizumab (1.25 mg in 0.05 mL) every 6-12 weeks. Treatment was discontinued at patient request or if there was no measurable response to therapy. Main outcome measures included best corrected visual acuity, ophthalmic examination, retinal photography, and angiography. Results: Bevacizumab treatment was followed by reductions in retinal hemorrhage, exudation, and edema. Visual acuities were stable or improved in 86% (n = 18). Three patients discontinued therapy. Each was legally blind before treatment (n = 1), experienced little to no subjective improvement (n = 2), or was poorly compliant (n = 2). Three patients (14%) regained 2 or more lines of visual acuity. No ocular or systemic bevacizumab-related side effects were observed. Conclusions: Intravitreal bevacizumab can be used to treat radiation retinopathy. In most cases treatment was associated with decreased vascular leakage, stabilization, or improved vision. An anti-vascular endothelial growth factor strategy may reduce tissue damage associated with radiation vasculopathy and neuropathy

  11. Treatment of macular edema due to retinal vein occlusions

    Directory of Open Access Journals (Sweden)

    Channa R

    2011-05-01

    Full Text Available Roomasa Channa, Michael Smith, Peter A CampochiaroDepartments of Ophthalmology and Neuroscience, The Johns Hopkins University School of Medicine, Baltimore, MD, USA Abstract: Retinal vein occlusion (RVO is a prevalent retinal vascular disease, second only to diabetic retinopathy. Previously there was no treatment for central retinal vein occlusion (CRVO and patients were simply observed for the development of severe complications, generally resulting in poor visual outcomes. The only treatment for branch vein occlusion (BRVO was grid laser photocoagulation, which reduces edema very slowly and provides benefit in some, but not all patients. Within the past year, clinical trials have demonstrated the effects of three new pharmacologic treatments, ranibizumab, triamcinolone acetonide, and dexamethasone implants. The benefit/risk ratio is best for intraocular injections of ranibizumab, making this first-line therapy for most patients with CRVO or BRVO, while intraocular steroids are likely to play adjunctive roles. Standard care for patients with RVO has changed and will continue to evolve as results with other new agents are revealed.Keywords: vascular endothelial growth factor, triamcinolone acetonide, dexamethosone implant, sustained release, vascular leakage, ischemia

  12. Suppressing thyroid hormone signaling preserves cone photoreceptors in mouse models of retinal degeneration

    OpenAIRE

    Ma, Hongwei; Thapa, Arjun; Morris, Lynsie; Redmond, T Michael; Baehr, Wolfgang; Ding, Xi-Qin

    2014-01-01

    Photoreceptors degenerate in a wide array of hereditary retinal diseases and age-related macular degeneration. There is currently no treatment available for retinal degenerations. While outnumbered roughly 20:1 by rods in the human retina, it is the cones that mediate color vision and visual acuity, and their survival is critical for vision. In this communication, we investigate whether thyroid hormone (TH) signaling affects cone viability in retinal degeneration mouse models. TH signaling is...

  13. Angiography reveals novel features of the retinal vasculature in healthy and diabetic mice.

    Science.gov (United States)

    McLenachan, Samuel; Magno, Aaron Len; Ramos, David; Catita, Joana; McMenamin, Paul G; Chen, Fred Kuanfu; Rakoczy, Elizabeth Piroska; Ruberte, Jesus

    2015-09-01

    The mouse retina is a commonly used animal model for the study of pathogenesis and treatment of blinding retinal vascular diseases such as diabetic retinopathy. In this study, we aimed to characterize normal and pathological variations in vascular anatomy in the mouse retina using fluorescein angiography visualized with scanning laser ophthalmoscopy and optical coherence tomography (SLO-OCT). We examined eyes from C57BL/6J wild type mice as well as the Ins2(Akita) and Akimba mouse models of diabetic retinopathy using the Heidelberg Retinal Angiography (HRA) and OCT system. Angiography was performed on three focal planes to examine distinct vascular layers. For comparison with angiographic data, ex vivo analyses, including Indian ink angiography, histology and 3D confocal scanning laser microscopy were performed in parallel. All layers of the mouse retinal vasculature could be readily visualized during fluorescein angiography by SLO-OCT. Blood vessel density was increased in the deep vascular plexus (DVP) compared with the superficial vascular plexus (SVP). Arteriolar and venular typologies were established and structural differences were observed between venular types. Unexpectedly, the hyaloid artery was found to persist in 15% of C57BL/6 mice, forming anastomoses with peripheral retinal capillaries. Fluorescein leakage was easily detected in Akimba retinae by angiography, but was not observed in Ins2(Akita) mice. Blood vessel density was increased in the DVP of 6 month old Ins2(Akita) mice, while the SVP displayed reduced branching in precapillary arterioles. In summary, we present the first comprehensive characterization of the mouse retinal vasculature by SLO-OCT fluorescein angiography. Using this clinical imaging technique, we report previously unrecognized variations in C57BL/6J vascular anatomy and novel features of vascular retinopathy in the Ins2(Akita) mouse model of diabetes. PMID:26122048

  14. Inhibition of the alternative complement pathway preserves photoreceptors after retinal injury.

    Science.gov (United States)

    Sweigard, J Harry; Matsumoto, Hidetaka; Smith, Kaylee E; Kim, Leo A; Paschalis, Eleftherios I; Okonuki, Yoko; Castillejos, Alexandra; Kataoka, Keiko; Hasegawa, Eiichi; Yanai, Ryoji; Husain, Deeba; Lambris, John D; Vavvas, Demetrios; Miller, Joan W; Connor, Kip M

    2015-07-22

    Degeneration of photoreceptors is a primary cause of vision loss worldwide, making the underlying mechanisms surrounding photoreceptor cell death critical to developing new treatment strategies. Retinal detachment, characterized by the separation of photoreceptors from the underlying retinal pigment epithelium, is a sight-threatening event that can happen in a number of retinal diseases. The detached photoreceptors undergo apoptosis and programmed necrosis. Given that photoreceptors are nondividing cells, their loss leads to irreversible visual impairment even after successful retinal reattachment surgery. To better understand the underlying disease mechanisms, we analyzed innate immune system regulators in the vitreous of human patients with retinal detachment and correlated the results with findings in a mouse model of retinal detachment. We identified the alternative complement pathway as promoting early photoreceptor cell death during retinal detachment. Photoreceptors down-regulate membrane-bound inhibitors of complement, allowing for selective targeting by the alternative complement pathway. When photoreceptors in the detached retina were removed from the primary source of oxygen and nutrients (choroidal vascular bed), the retina became hypoxic, leading to an up-regulation of complement factor B, a key mediator of the alternative pathway. Inhibition of the alternative complement pathway in knockout mice or through pharmacological means ameliorated photoreceptor cell death during retinal detachment. Our current study begins to outline the mechanism by which the alternative complement pathway facilitates photoreceptor cell death in the damaged retina. PMID:26203084

  15. Treatment with polyamine oxidase inhibitor reduces microglial activation and limits vascular injury in ischemic retinopathy.

    Science.gov (United States)

    Patel, C; Xu, Z; Shosha, E; Xing, J; Lucas, R; Caldwell, R W; Caldwell, R B; Narayanan, S P

    2016-09-01

    Retinal vascular injury is a major cause of vision impairment in ischemic retinopathies. Insults such as hyperoxia, oxidative stress and inflammation contribute to this pathology. Previously, we showed that hyperoxia-induced retinal neurodegeneration is associated with increased polyamine oxidation. Here, we are studying the involvement of polyamine oxidases in hyperoxia-induced injury and death of retinal vascular endothelial cells. New-born C57BL6/J mice were exposed to hyperoxia (70% O2) from postnatal day (P) 7 to 12 and were treated with the polyamine oxidase inhibitor MDL 72527 or vehicle starting at P6. Mice were sacrificed after different durations of hyperoxia and their retinas were analyzed to determine the effects on vascular injury, microglial cell activation, and inflammatory cytokine profiling. The results of this analysis showed that MDL 72527 treatment significantly reduced hyperoxia-induced retinal vascular injury and enhanced vascular sprouting as compared with the vehicle controls. These protective effects were correlated with significant decreases in microglial activation as well as levels of inflammatory cytokines and chemokines. In order to model the effects of polyamine oxidation in causing microglial activation in vitro, studies were performed using rat brain microvascular endothelial cells treated with conditioned-medium from rat retinal microglia stimulated with hydrogen peroxide. Conditioned-medium from activated microglial cultures induced cell stress signals and cell death in microvascular endothelial cells. These studies demonstrate the involvement of polyamine oxidases in hyperoxia-induced retinal vascular injury and retinal inflammation in ischemic retinopathy, through mechanisms involving cross-talk between endothelial cells and resident retinal microglia. PMID:27239699

  16. Duration of streptozotocin-induced diabetes differentially affects p38-mitogen-activated protein kinase (MAPK phosphorylation in renal and vascular dysfunction

    Directory of Open Access Journals (Sweden)

    Gupta Akanksha

    2005-03-01

    Full Text Available Abstract Background In the present study we tested the hypothesis that progression of streptozotocin (STZ-induced diabetes (14-days to 28-days would produce renal and vascular dysfunction that correlate with altered p38- mitogen-activated protein kinase (p38-MAPK phosphorylation in kidneys and thoracic aorta. Methods Male Sprague Dawley rats (350–400 g were randomized into three groups: sham (N = 6, 14-days diabetic (N = 6 and 28-days diabetic rats (N = 6. Diabetes was induced using a single tail vein injection of STZ (60 mg/kg, I.V. on the first day. Rats were monitored for 28 days and food, water intake and plasma glucose levels were noted. At both 14-days and 28-days post diabetes blood samples were collected and kidney cortex, medulla and aorta were harvested from each rat. Results The diabetic rats lost body weight at both 14-days (-10% and 28-days (-13% more significantly as compared to sham (+10% group. Glucose levels were significantly elevated in the diabetic rats at both 14-days and 28-days post-STZ administration. Renal dysfunction as evidenced by renal hypertrophy, increased plasma creatinine concentration and reduced renal blood flow was observed in 14-days and 28-days diabetes. Vascular dysfunction as evidenced by decreased carotid blood flow was observed in 14-days and 28-days diabetes. We observed an up-regulation of inducible nitric oxide synthase (iNOS, prepro endothelin-1 (preproET-1 and phosphorylated p38-MAPK in thoracic aorta and kidney cortex but not in kidney medulla in 28-days diabetes group. Conclusion The study provides evidence that diabetes produces vascular and renal dysfunction with a profound effect on signaling mechanisms at later stage of diabetes.

  17. Reduction of homocysteine in elderly with heart failure improved vascular function and blood pressure control but did not affect inflammatory activity

    DEFF Research Database (Denmark)

    Andersson, Sven; Edvinsson, Marie-Louise; Edvinsson, Lars

    2005-01-01

    the hyperhomocysteinaemia and if so, in turn, would improve the associated parameters. This was an open study without placebo control on heart failure patients with plasma homocysteine > 15 microM. Measurements of cutaneous vascular reactivity, blood pressure, inflammatory activity and endothelial function were performed...... before and after intervention with intra-individual comparisons. The treatment reduced homocysteine to near normal values and enhanced the hyperaemic response to acetylcholine related to the response to heat. The mean arterial blood pressure and pulse rate was reduced. There was no effect on inflammatory...

  18. 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.

  19. 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. PMID:21611771

  20. Small Animal Retinal Imaging

    Science.gov (United States)

    Choi, WooJhon; Drexler, Wolfgang; Fujimoto, James G.

    Developing and validating new techniques and methods for small animal imaging is an important research area because there are many small animal models of retinal diseases such as diabetic retinopathy, age-related macular degeneration, and glaucoma [1-6]. Because the retina is a multilayered structure with distinct abnormalities occurring in different intraretinal layers at different stages of disease progression, there is a need for imaging techniques that enable visualization of these layers individually at different time points. Although postmortem histology and ultrastructural analysis can be performed for investigating microscopic changes in the retina in small animal models, this requires sacrificing animals, which makes repeated assessment of the same animal at different time points impossible and increases the number of animals required. Furthermore, some retinal processes such as neurovascular coupling cannot be fully characterized postmortem.

  1. 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

  2. Retinal flow cytometer

    OpenAIRE

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

  3. Aphakic retinal detachment.

    OpenAIRE

    Le Mesurier, R; Vickers, S; Booth-Mason, S; Chignell, A H

    1985-01-01

    A study of 132 cases of aphakic retinal detachment (ARD) following mainly intracapsular cataract surgery has been made. Forty-nine cases (37%) were found to have vitreous incarcerated into the cataract section out of a total of 54 (41%) cases who had suffered a vitreous complication during cataract surgery. A study of the characteristics of ARD reveals that those cases having had a vitreous complication in the management of their cataracts are more likely to develop detachment within three mo...

  4. Spectral domain optical coherence tomography features of multiple subfoveal retinal pigment epithelial tears after intravitreal bevacizumab

    OpenAIRE

    Chalam Kakarla; Murthy Ravi; Gupta Shailesh; Brar Vikram

    2011-01-01

    Retinal pigment epithelial (RPE) tear has been described to occur spontaneously, after laser photocoagulation and in recent times, after intravitreal injection of anti-vascular endothelial growth factor (VEGF) agents. In the latter case, the rapid contraction of the choroidal vascular membrane underneath a serous RPE detachment is believed to be the underlying cause. Preservation of good visual acuity after the occurrence of RPE tear with continued use of intravitreal VEGF agents has been rep...

  5. 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.

  6. VEGF-B inhibits hyperglycemia- and Macugen-induced retinal apoptosis

    Science.gov (United States)

    Huang, Delong; Zhao, Chen; Ju, Rong; Kumar, Anil; Tian, Geng; Huang, Lijuan; Zheng, Lei; Li, Xianglin; Liu, Lixian; Wang, Shasha; Ren, Xiangrong; Ye, Zhimin; Chen, Wei; Xing, Liying; Chen, Qishan; Gao, Zhiqin; Mi, Jia; Tang, Zhongshu; Wang, Bin; Zhang, Shuping; Lee, Chunsik; Li, Xuri

    2016-01-01

    Vascular endothelial growth factor B (VEGF-B) was discovered a long time ago. However, its role in hyperglycemia- and VEGF-A inhibition-induced retinal apoptosis remains unknown thus far. Yet, drugs that can block VEGF-B are being used to treat patients with diabetic retinopathy and other ocular neovascular diseases. It is therefore urgent to have a better understanding of the function of VEGF-B in these pathologies. Here, we report that both streptozotocin (STZ)-induced diabetes in rats and Macugen intravitreal injection in mice leads to retinal apoptosis in retinal ganglion cell and outer nuclear layers respectively. Importantly, VEGF-B treatment by intravitreal injection markedly reduced retinal apoptosis in both models. We further reveal that VEGF-B and its receptors, vascular endothelial growth factor 1 (VEGFR1) and neuropilin 1 (NP1), are abundantly expressed in rat retinae and choroids and are upregulated by high glucose with concomitant activation of Akt and Erk. These data highlight an important function of VEGF-B in protecting retinal cells from apoptosis induced by hyperglycemia and VEGF-A inhibition. VEGF-B may therefore have a therapeutic potential in treating various retinal degenerative diseases, and modulation of VEGF-B activity in the eye needs careful consideration. PMID:27189805

  7. VEGF-B inhibits hyperglycemia- and Macugen-induced retinal apoptosis.

    Science.gov (United States)

    Huang, Delong; Zhao, Chen; Ju, Rong; Kumar, Anil; Tian, Geng; Huang, Lijuan; Zheng, Lei; Li, Xianglin; Liu, Lixian; Wang, Shasha; Ren, Xiangrong; Ye, Zhimin; Chen, Wei; Xing, Liying; Chen, Qishan; Gao, Zhiqin; Mi, Jia; Tang, Zhongshu; Wang, Bin; Zhang, Shuping; Lee, Chunsik; Li, Xuri

    2016-01-01

    Vascular endothelial growth factor B (VEGF-B) was discovered a long time ago. However, its role in hyperglycemia- and VEGF-A inhibition-induced retinal apoptosis remains unknown thus far. Yet, drugs that can block VEGF-B are being used to treat patients with diabetic retinopathy and other ocular neovascular diseases. It is therefore urgent to have a better understanding of the function of VEGF-B in these pathologies. Here, we report that both streptozotocin (STZ)-induced diabetes in rats and Macugen intravitreal injection in mice leads to retinal apoptosis in retinal ganglion cell and outer nuclear layers respectively. Importantly, VEGF-B treatment by intravitreal injection markedly reduced retinal apoptosis in both models. We further reveal that VEGF-B and its receptors, vascular endothelial growth factor 1 (VEGFR1) and neuropilin 1 (NP1), are abundantly expressed in rat retinae and choroids and are upregulated by high glucose with concomitant activation of Akt and Erk. These data highlight an important function of VEGF-B in protecting retinal cells from apoptosis induced by hyperglycemia and VEGF-A inhibition. VEGF-B may therefore have a therapeutic potential in treating various retinal degenerative diseases, and modulation of VEGF-B activity in the eye needs careful consideration. PMID:27189805

  8. Clinical and immunological features of retinal vasculitis in systemic diseases

    Directory of Open Access Journals (Sweden)

    Paović Jelena

    2009-01-01

    . Conclusion. Systemic diseases such as Behcet's syndrome, collagen vascular diseases, systemic granulomatous diseases (sarcoidosis and tuberculosis were the main causes of retinal vasculitis. Knowledge of the symptomatology and pathogenesis of retinal vasculitis is of the major significance for the diagnosis and therapy of the disease.

  9. What Is Vascular Disease?

    Science.gov (United States)

    ... our CEO Board of Directors Scientific Advisory Board History of Vascular Cures Impact Contact Us Vascular Disease What is Vascular Disease? Education and Awareness Vascular Diseases Abdominal Aortic Aneurysm Aortic ...

  10. Diabetes and Vascular Disease

    Science.gov (United States)

    ... our CEO Board of Directors Scientific Advisory Board History of Vascular Cures Impact Contact Us Vascular Disease What is Vascular Disease? Education and Awareness Vascular Diseases Abdominal Aortic Aneurysm Aortic ...

  11. Multifractal Analysis of Human Retinal Vessels

    CERN Document Server

    Stosic, T

    2004-01-01

    In this work it is shown that vascular structures of the human retina represent geometrical multifractals, characterized by a hierarchy of exponents rather then a single fractal dimension. A number of retinal images from the STARE database (www.parl.clemson.edu/stare) are analyzed, corresponding to both normal and pathological states of the retina. In all studied cases a clearly multifractal behavior is observed, where capacity dimension is always found to be smaller then the information dimension, which is in turn always smaller then the correlation dimension, all the three being significantly lower then the DLA (Diffusion Limited Aggregation) fractal dimension. We also observe a tendency of images corresponding to the normal state of the retina to have higher generalized dimensions and a wider spectrum range, in comparison with the pathological cases.

  12. Connective tissue growth factor is necessary for retinal capillary basal lamina thickening in diabetic mice.

    NARCIS (Netherlands)

    Kuiper, E.J.; Zijderveld, R van; Roestenberg, P.M.H.; Lyons, K.M.; Goldschmeding, R.; Klaassen, I.; Noorden, C.J.F. van; Schlingemann, R.O.

    2008-01-01

    Experimental prevention of basal lamina (BL) thickening of retinal capillaries ameliorates early vascular changes caused by diabetes. Connective tissue growth factor (CTGF) is upregulated early in diabetes in the human retina and is a potent inducer of expression of BL components. We hypothesize tha

  13. Quantitative Measurement of Changes in Retinal Vessel Diameter in Ocular Fundus Images

    DEFF Research Database (Denmark)

    Pedersen, Lars; Grunkin, Michael; Ersbøll, Bjarne Kjær;

    1999-01-01

    The Change in diameter of retinal vessels as a funcion of increasing distance to the optic disc is believed to be indicative of the risk level of various vascular diseases such as generalised arteriosclerosis and Diabetes Mellitus. In particular, Focal Arteriolar Narrowing (FAN) is considered...

  14. 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

  15. 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.

  16. 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

    AIMS/HYPOTHESIS: The purpose of the study was to evaluate the association between retinal vascular calibre and micro- and macrovascular complications in a population-based cohort of Danish type 1 diabetic patients. METHODS: This was a cross-sectional study of 208 long-surviving type 1 diabetic...... SD decrease in CRAE), but not neuropathy (OR 1.10, 95% CI 0.70-1.71, per SD decrease in CRAE). Retinal venular calibre was not associated with any micro- or macrovascular complications. CONCLUSIONS/INTERPRETATION: In type 1 diabetic patients, retinal arteriolar narrowing is associated with...... nephropathy and macrovascular disease independently of other clinical characteristics. If supported by further prospective studies, measurement of retinal vessel diameter may allow a non-invasive evaluation of the risk of diabetes-related complications....

  17. In vivo integrated photoacoustic ophthalmoscopy, optical coherence tomography, and scanning laser ophthalmoscopy for retinal imaging

    Science.gov (United States)

    Song, Wei; Zhang, Rui; Zhang, Hao F.; Wei, Qing; Cao, Wenwu

    2012-12-01

    The physiological and pathological properties of retina are closely associated with various optical contrasts. Hence, integrating different ophthalmic imaging technologies is more beneficial in both fundamental investigation and clinical diagnosis of several blinding diseases. Recently, photoacoustic ophthalmoscopy (PAOM) was developed for in vivo retinal imaging in small animals, which demonstrated the capability of imaging retinal vascular networks and retinal pigment epithelium (RPE) at high sensitivity. We combined PAOM with traditional imaging modalities, such as fluorescein angiography (FA), spectral-domain optical coherence tomography (SD-OCT), and auto-fluorescence scanning laser ophthalmoscopy (AF-SLO), for imaging rats and mice. The multimodal imaging system provided more comprehensive evaluation of the retina based on the complementary imaging contrast mechanisms. The high-quality retinal images show that the integrated ophthalmic imaging system has great potential in the investigation of blinding disorders.

  18. Knock-down of pantothenate kinase 2 severely affects the development of the nervous and vascular system in zebrafish, providing new insights into PKAN disease.

    Science.gov (United States)

    Zizioli, Daniela; Tiso, Natascia; Guglielmi, Adele; Saraceno, Claudia; Busolin, Giorgia; Giuliani, Roberta; Khatri, Deepak; Monti, Eugenio; Borsani, Giuseppe; Argenton, Francesco; Finazzi, Dario

    2016-01-01

    Pantothenate Kinase Associated Neurodegeneration (PKAN) is an autosomal recessive disorder with mutations in the pantothenate kinase 2 gene (PANK2), encoding an essential enzyme for Coenzyme A (CoA) biosynthesis. The molecular connection between defects in this enzyme and the neurodegenerative phenotype observed in PKAN patients is still poorly understood. We exploited the zebrafish model to study the role played by the pank2 gene during embryonic development and get new insight into PKAN pathogenesis. The zebrafish orthologue of hPANK2 lies on chromosome 13, is a maternal gene expressed in all development stages and, in adult animals, is highly abundant in CNS, dorsal aorta and caudal vein. The injection of a splice-inhibiting morpholino induced a clear phenotype with perturbed brain morphology and hydrocephalus; edema was present in the heart region and caudal plexus, where hemorrhages with reduction of blood circulation velocity were detected. We characterized the CNS phenotype by studying the expression pattern of wnt1 and neurog1 neural markers and by use of the Tg(neurod:EGFP/sox10:dsRed) transgenic line. The results evidenced that downregulation of pank2 severely impairs neuronal development, particularly in the anterior part of CNS (telencephalon). Whole-mount in situ hybridization analysis of the endothelial markers cadherin-5 and fli1a, and use of Tg(fli1a:EGFP/gata1a:dsRed) transgenic line, confirmed the essential role of pank2 in the formation of the vascular system. The specificity of the morpholino-induced phenotype was proved by the restoration of a normal development in a high percentage of embryos co-injected with pank2 mRNA. Also, addition of pantethine or CoA, but not of vitamin B5, to pank2 morpholino-injected embryos rescued the phenotype with high efficiency. The zebrafish model indicates the relevance of pank2 activity and CoA homeostasis for normal neuronal development and functioning and provides evidence of an unsuspected role for this

  19. New Wrinkles in Retinal Densitometry

    OpenAIRE

    Masella, Benjamin D.; Hunter, Jennifer J.; Williams, David R.

    2014-01-01

    Retinal densitometry has the potential to provide objective information about the function of the retina. However, a number of factors complicate the interpretation of retinal reflectance. We have discovered additional sources of reflectance change and have defined a method to minimize their impact.

  20. Genetics Home Reference: retinitis pigmentosa

    Science.gov (United States)

    ... by the combination of vision loss and hearing loss beginning early in life. Retinitis pigmentosa is also a feature of several other genetic syndromes, including Bardet-Biedl syndrome ; Refsum disease ; and neuropathy, ... for retinitis pigmentosa lead to a gradual loss of rods and cones in the retina. The ...

  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. 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.

  3. 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.

  4. IDENTIFYING ALL TRUE VESSELS FROM SEGMENTED RETINAL IMAGES

    Directory of Open Access Journals (Sweden)

    G. Delucta Mary

    2015-11-01

    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.

  5. Neuroprotective effect of minocycline in a rat model of branch retinal vein occlusion.

    Science.gov (United States)

    Sun, Chuan; Li, Xiao-Xin; He, Xiang-Jun; Zhang, Qi; Tao, Yong

    2013-08-01

    Branch retinal vein occlusion (BRVO) is the second most frequent retinal vascular disorder. Currently the first-line therapies for BRVO include anti-VEGF and dexamethasone implant treatment, however, with direct or indirect damage on retinal neurons, it has limited effect in improving patients visual acuity. Therefore, novel treatments with neuroprotective effect for BRVO retina were expected. Minocycline is a semisynthetic, broad spectrum tetracycline antibiotic with high penetration through the blood brain barrier. The neuroprotective effects of minocycline have been shown in various central nervous system (CNS) disease. Since both CNS and retina were composed of neurons and glials, it is reasonable to expect a neuroprotective effect by minocycline for BRVO retina. Therefore, the aim of the present study was to study whether minocycline has neuroprotective effect in branch retinal vein occlusion (BRVO) and the possible underlying molecular basis. We created BRVO in rats using laser photocoagulation. The animals were then randomly divided into 4 groups to evaluate the effect of minocycline: group A: minocycline 45 mg/kg intraperitoneal injection (i.p.), group B: minocycline 90 mg/kg i.p., group C: normal saline i.p., group D: sham injection. Fundus photography and fluorescein angiography (FA) were conducted. The changes in thickness of retinal layers were measured with optical coherence tomography (OCT) in vivo. We found that retinal edema occurred predominantly in the inner retinal layers. Intraperitoneal administration of minocycline significantly ameliorated retinal edema in the early stage of BRVO. We performed Full field Electroretinography (ffERG) to evaluate retinal function and found that the reduction of b wave amplitude decreased in the combined maximal response. The expressional levels of apoptosis related genes (Bax, Bcl-2) and inflammation related genes (IL-1 β, TNF α, MCP-1 and CCR2) were measured by real-time PCR, the results showed that

  6. Reduction of homocysteine in elderly with heart failure improved vascular function and blood pressure control but did not affect inflammatory activity.

    Science.gov (United States)

    Andersson, Sven E; Edvinsson, Marie-Louise; Edvinsson, Lars

    2005-11-01

    We have previously shown that hyperhomocysteinaemia is common in elderly heart failure patients, and is associated with endothelial dysfunction, impaired vasodilatory capacity and a low-grade inflammation. In the present study we examined if supplementation with B6, B12 and folate could normalize the hyperhomocysteinaemia and if so, in turn, would improve the associated parameters. This was an open study without placebo control on heart failure patients with plasma homocysteine > 15 microM. Measurements of cutaneous vascular reactivity, blood pressure, inflammatory activity and endothelial function were performed before and after intervention with intra-individual comparisons. The treatment reduced homocysteine to near normal values and enhanced the hyperaemic response to acetylcholine related to the response to heat. The mean arterial blood pressure and pulse rate was reduced. There was no effect on inflammatory activity, plasma levels of von Willebrand factor, subjective health quality or the hyperaemic responses to sodium nitroprusside or local warming. Hyperhomocysteinaemia in heart failure patients is multifactorial in origin. Folate deficiency, inflammatory activity and reduced renal function could be contributing. It is suggested that supplementation with B-vitamins can improve the vasodilatory capacity and reduce the blood pressure but additional studies are required to confirm this. PMID:16236143

  7. 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.

  8. Antisense Oligonucleotide Therapy for Inherited Retinal Dystrophies.

    Science.gov (United States)

    Gerard, Xavier; Garanto, Alejandro; Rozet, Jean-Michel; Collin, Rob W J

    2016-01-01

    Inherited retinal dystrophies (IRDs) are an extremely heterogeneous group of genetic diseases for which currently no effective treatment strategies exist. Over the last decade, significant progress has been made utilizing gene augmentation therapy for a few genetic subtypes of IRD, although several technical challenges so far prevent a broad clinical application of this approach for other forms of IRD. Many of the mutations leading to these retinal diseases affect pre-mRNA splicing of the mutated genes . Antisense oligonucleotide (AON)-mediated splice modulation appears to be a powerful approach to correct the consequences of such mutations at the pre-mRNA level , as demonstrated by promising results in clinical trials for several inherited disorders like Duchenne muscular dystrophy, hypercholesterolemia and various types of cancer. In this mini-review, we summarize ongoing pre-clinical research on AON-based therapy for a few genetic subtypes of IRD , speculate on other potential therapeutic targets, and discuss the opportunities and challenges that lie ahead to translate splice modulation therapy for retinal disorders to the clinic. PMID:26427454

  9. [Retinal venous obliteration and general pathology].

    Science.gov (United States)

    Aconiu, M; Mihălaş, G; Nemoianu, C

    1992-01-01

    The study of 148 retinal venous obliterations have shown 81 occlusions of central vein and 67 of I and II venous branch. A number of 90 was for the feminine gender (sex) and 59 for the masculine sex. The average age for the appearance of the venous occlusions was 62 years old, having extreme limits between 36-84 years old. Bilaterality has been for 3 cases. Concerning the associated medical affections, hypertension was for 67 patients, myocardiosclerosis have been mentioned for 67 patients, atherosclerosis for 21 patients, pulmonary scleroemphisis for 12 patients. Arterial hypertension with its aspersion that is arteriosclerosis are the main factors that have generated retinal circulation modifyings and have led to a degree of arterial insufficiency. Comparing the ophthalmological aspect to the pressure in the ophthalmic artery, most of the patients had a concordance of TACR and the retinal and choroidal angiosclerosis. The oscillometric examination to the inferior members has been effectuated for 21 patients and it has shown diminished values only for 3 cases. The forecast of the disease is still reserved. Following a group of 40 patients having OVR between 5 and 15 years old it has been established an average survival of 6.2 years. It is mentioned that 26% between these have dyed during the first six years. PMID:1520668

  10. Retinal vascular and structural dynamics during acute hyperglycaemia

    DEFF Research Database (Denmark)

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

    2015-01-01

    oximetry, macular perfusion velocities and optical coherence tomographic measurement of subfoveal choroidal thickness every 30 min during a 3-hr 75 g oral glucose tolerance test (OGTT). Patients paused antidiabetic therapy for 1 week prior to the OGTT. RESULTS: Plasma glucose (PG) and fluctuations in PG...

  11. 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.

  12. 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.

  13. Vascular endothelial growth factor trap-eye (Aflibercept) for the management of diabetic macular edema.

    Science.gov (United States)

    Moradi, Ahmadreza; Sepah, Yasir Jamal; Sadiq, Mohammad Ali; Nasir, Humzah; Kherani, Salima; Sophie, Raafay; Do, Diana V; Nguyen, Quan Dong

    2013-12-15

    Diabetic retinopathy (DR) is the most common cause of visual loss among working age individuals. Diabetic macular edema (DME) is an important complication of DR that affects around one third of the patients with DR. Several treatments have been approved for DME ranging from blood pressure and glycemic control to photocoagulation and more recently the use of vascular endothelial growth factor (VEGF) antagonists. The index review discusses aflibercept (EYLEA(®)-Regeneron Pharmaceuticals, Inc., Tarrytown, New York, NY, and Bayer Healthcare Pharmaceuticals, Berlin, Germany) in the context of other VEGF antagonists currently available for the treatment of DME. A systematic search of literature was conducted on PubMed, Scopus, and Google Scholar with no limitation on language or year of publication. Pre-clinical studies of aflibercept have shown a higher affinity of this molecule for vascular endothelial growth factor A (VEGF-A) along with a longer duration of action as compared to other VEGF antagonists. Recent clinical trials have shown visual outcome results for aflibercept to be similarly favorable as compared to other available agents with the added benefit of fewer required injections and less frequent monitoring. Aflibercept presents a potential exciting new addition to the armamentarium of current VEGF antagonists available for the treatment of DME and other retinal vascular diseases. However, further studies are indicated to confirm the role, safety, and efficacy of aflibercept for DME. PMID:24379921

  14. 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 ...

  15. CRB1 mutations in inherited retinal dystrophies.

    OpenAIRE

    Bujakowska, Kinga; Audo, Isabelle; Mohand-Saïd, Saddek; Lancelot, Marie-Elise; Antonio, Aline; Germain, Aurore; Léveillard, Thierry; Letexier, Mélanie; Saraiva, Jean-Paul; Lonjou, Christine; Carpentier, Wassila; Sahel, José-Alain; Bhattacharya, Shomi; Zeitz, Christina

    2012-01-01

    Mutations in the CRB1 gene are associated with variable phenotypes of severe retinal dystrophies, ranging from leber congenital amaurosis (LCA) to rod-cone dystrophy, also called retinitis pigmentosa (RP). Moreover, retinal dystrophies resulting from CRB1 mutations may be accompanied by specific fundus features: preservation of the para-arteriolar retinal pigment epithelium (PPRPE) and retinal telangiectasia with exudation (also referred to as Coats-like vasculopathy). In this publication, we...

  16. Retinal synaptic regeneration via microfluidic guiding channels

    OpenAIRE

    Ping-Jung Su; Zongbin Liu; Kai Zhang; Xin Han; Yuki Saito; Xiaojun Xia; Kenji Yokoi; Haifa Shen; Lidong Qin

    2015-01-01

    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 demon...

  17. Retinal Image Preprocessing: Background and Noise Segmentation

    OpenAIRE

    Usman Akram

    2012-01-01

    Retinal images are used for the automated screening and diagnosis of diabetic retinopathy. The retinal image quality must be improved for the detection of features and abnormalities and for this purpose preprocessing of retinal images is vital. In this paper, we present a novel automated approach for preprocessing of colored retinal images. The proposed technique improves the quality of input retinal image by separating the background and noisy area from the overall image. It contains coarse ...

  18. Vascular dysregulation in normal-tension glaucoma is not affected by structure and function of the microcirculation or macrocirculation at rest: a case-control study.

    Science.gov (United States)

    Bossuyt, Jelle; Vandekerckhove, Gwendolijn; De Backer, Tine L M; Van de Velde, Sandrien; Azermai, Majda; Stevens, Anna-Maria; Kestelyn, Philippe; Raemdonck, Tia; Segers, Patrick; Vanmolkot, Floris; Van Bortel, Luc M

    2015-01-01

    In normal-tension glaucoma (NTG), optic nerve damage occurs despite a normal intraocular pressure. Studies implicating systemic blood pressure or, more recently, arterial stiffness in the pathophysiology of NTG have produced conflicting results. Our aim was to investigate whether NTG is associated with alterations in the macrocirculation or microcirculation, cardiac function, and peripheral and central hemodynamics. Thirty patients with NTG (mean age 65 years, range 46-79) and 33 healthy subjects (mean age 67 years, range 42-79) matched for age and sex were included in the study. Exclusion criteria (for both cases and controls) were history of cardiovascular disease, diabetes mellitus, severe hypertension, and hypercholesterolemia. Aortic stiffness was measured using carotid-femoral pulse wave velocity (PWV), central hemodynamics using carotid artery applanation tonometry, and diameter, stiffness, and intima-media thickness (IMT) of the carotid and femoral artery using echo-tracking. Total peripheral resistance index (TPRI) was derived from mean arterial pressure and cardiac index, measured using ultrasound. There were no statistically significant differences in arterial structure nor function between NTG patients and age and sex-matched controls. NTG versus controls, respectively: brachial blood pressure 126 ± 15/77 ± 8 versus 127 ± 16/76 ± 7 mm Hg, P = 0.81; carotid-femoral PWV 9.8 ± 2.1 versus 10.1 ± 1.9 m/s, P = 0.60; TPRI 1833 ± 609 versus 1779 ± 602 dyne.s/cm5/m2, P = 0.79; and carotid IMT 0.65 ± 0.14 versus 0.68 ± 0.13 mm, P = 0.39. This study could not show an association of NTG with altered IMT, arterial stiffness, total peripheral resistance, cardiac output, and peripheral or central hemodynamics at rest. Although the majority of these NTG patients do exhibit symptoms of vascular dysregulation, in the present study this was not translated into alterations in the microcirculation or macrocirculation at rest. PMID:25590850

  19. Retinal detachment following excimer laser

    OpenAIRE

    Charteris, D; Cooling, R; Lavin, M; McLeod, D

    1997-01-01

    AIMS—To report the clinical presentation, surgical management, and outcome of retinal detachment following excimer laser.
METHODS—Retrospective analysis of retinal detachments observed in 11 eyes of 10 myopic patients who had previously undergone photorefractive keratectomy (PRK) or phototherapeutic keratectomy (PTK) by excimer laser.
RESULTS—Symptoms of visual loss in two eyes were initially attributed to corneal haze. In 10 of 11 eyes visualisation of the retinal detachment and causative br...

  20. Evaluation of the Retinal Vasculature in Hypertension and Chronic Kidney Disease in an Elderly Population of Irish Nuns.

    Directory of Open Access Journals (Sweden)

    Amy McGowan

    Full Text Available Chronic kidney disease (CKD and hypertension are global public health problems associated with considerable morbidity, premature mortality and attendant healthcare costs. Previous studies have highlighted that non-invasive examination of the retinal microcirculation can detect microvascular pathology that is associated with systemic disorders of the circulatory system such as hypertension. We examined the associations between retinal vessel caliber (RVC and fractal dimension (DF, with both hypertension and CKD in elderly Irish nuns.Data from 1233 participants in the cross-sectional observational Irish Nun Eye Study (INES were assessed from digital photographs with a standardized protocol using computer-assisted software. Multivariate regression analyses were used to assess associations with hypertension and CKD, with adjustment for age, body mass index (BMI, refraction, fellow eye RVC, smoking, alcohol consumption, ischemic heart disease (IHD, cerebrovascular accident (CVA, diabetes and medication use.In total, 1122 (91% participants (mean age: 76.3 [range: 56-100] years had gradable retinal images of sufficient quality for blood vessel assessment. Hypertension was significantly associated with a narrower central retinal arteriolar equivalent (CRAE in a fully adjusted analysis (P = 0.002; effect size = -2.16 μm; 95% confidence intervals [CI]: -3.51, -0.81 μm. No significant associations between other retinal vascular parameters and hypertension or between any retinal vascular parameters and CKD were found.Individuals with hypertension have significantly narrower retinal arterioles which may afford an earlier opportunity for tailored prevention and treatment options to optimize the structure and function of the microvasculature, providing additional clinical utility. No significant associations between retinal vascular parameters and CKD were detected.

  1. Flexible retinal electrode array

    Energy Technology Data Exchange (ETDEWEB)

    Okandan, Murat (Albuquerque, NM); Wessendorf, Kurt O. (Albuquerque, NM); Christenson, Todd R. (Albuquerque, NM)

    2006-10-24

    An electrode array which has applications for neural stimulation and sensing. The electrode array can include a large number of electrodes each of which is flexibly attached to a common substrate using a plurality of springs to allow the electrodes to move independently. The electrode array can be formed from a combination of bulk and surface micromachining, with electrode tips that can include an electroplated metal (e.g. platinum, iridium, gold or titanium) or a metal oxide (e.g. iridium oxide) for biocompatibility. The electrode array can be used to form a part of a neural prosthesis, and is particularly well adapted for use in an implantable retinal prosthesis where the electrodes can be tailored to provide a uniform gentle contact pressure with optional sensing of this contact pressure at one or more of the electrodes.

  2. 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.

  3. Telangiectasia retiniana parafoveal unilateral Unilateral parafoveal retinal telangiectasis

    Directory of Open Access Journals (Sweden)

    Mário Martins dos Santos Motta

    2007-10-01

    Full Text Available Telangiectasia retiniana é um termo inicialmente proposto por Reese, em 1956. Caracteriza-se por uma anormalidade vascular retiniana, com dilatação irregular e incompetência dos vasos. E.L.S., 44 anos, sexo masculino, branco, do Rio de Janeiro, com queixa de perda progressiva da visão em olho esquerdo (OE. Ao exame observamos acuidade visual (AV corrigida de 20/20 em olho direito (OD e 20/100 em OE. À fundoscopia, OD normal e OE apresentando dilatação capilar e exsudatos duros com aspecto circinado na região macular. Angiografia fluoresceínica e, após o resultado, injeção intravítrea de triancinolona em OE (4mg/0,1ml. Após um mês da injeção de triancinolona a AV em OE passou a 20/40, os exsudatos duros tornaram-se mais visíveis e a angiografia mostrou diminuição do vazamento do corante. Foi possível a realização de fotocoagulação com laser. A AV final corrigida foi de 20/20 em ambos os olhos. O tratamento com laser está amplamente difundido na literatura, porém optamos inicialmente pela injeção intravítrea de triancinolona. Pode-se considerar a injeção intravítrea de triancinolona em casos de telangiectasia retiniana parafoveal com redução importante da visão e alterações muito próximas à região avascular foveal. Entretanto, os resultados em longo prazo não são conhecidos e precisam ser confrontados com as outras opções de tratamento.Retinal telangiectasis was first described by Reese, in 1956. It is an abnormality of the retinal vessels, with irregular dilation and vessel failure. ELS, 44 years old, male, white, from Rio de Janeiro. His complaining was progressive visual loss in the left eye (OS. Corrected visual acuity (VA was 20/20 in the right eye (OD and 20/100 in OS. Fundoscopy in OD was normal, and in OS showed capillaries dilation and hard exsudates (circinate in macular area. After fluorescein angiogram, we performed intravitreal injection of triamcinolone acetonide (4mg/0.1ml in OS. One

  4. Society for Vascular Medicine

    Science.gov (United States)

    ... and find out! Patient Information Pages from Vascular Medicine August 2016 The Vascular Laboratory More info for ... Learn more. Trending Now: Hot Topics in Vascular Medicine Video Series Fibromuscular Dysplasia (FMD) with Drs. Jeffrey ...

  5. Msx2 alters the timing of retinal ganglion cells fate commitment and differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Shao-Yun, E-mail: jiangshaoyun@yahoo.com [School of Dentistry, Tianjin Medical University, 12 Qi Xiang Tai Street, Tianjin 300070 (China); Wang, Jian-Tao, E-mail: wangjiantao65@hotmail.com [Eye Center, Tianjin Medical University, 64 Tongan Road, Tianjin 300070 (China); Dohney Eye Institute, Keck School of Medicine, University of Southern California, 1355 San Pablo Street, DOH 314, Los Angeles, CA 90033 (United States)

    2010-05-14

    Timing of cell fate commitment determines distinct retinal cell types, which is believed to be controlled by a tightly coordinated regulatory program of proliferation, cell cycle exit and differentiation. Although homeobox protein Msx2 could induce apoptosis of optic vesicle, it is unclear whether Msx2 regulates differentiation and cell fate commitment of retinal progenitor cells (RPCs) to retinal ganglion cells (RGCs). In this study, we show that overexpression of Msx2 transiently suppressed the expression of Cyclin D1 and blocked cell proliferation. Meanwhile, overexpression of Msx2 delayed the expression of RGC-specific differentiation markers (Math5 and Brn3b), which showed that Msx2 could affect the timing of RGCs fate commitment and differentiation by delaying the timing of cell cycle exit of retinal progenitors. These results indicate Msx2 possesses dual regulatory functions in controlling cell cycle progression of retinal RPCs and timing of RGCs differentiation.

  6. Msx2 alters the timing of retinal ganglion cells fate commitment and differentiation

    International Nuclear Information System (INIS)

    Timing of cell fate commitment determines distinct retinal cell types, which is believed to be controlled by a tightly coordinated regulatory program of proliferation, cell cycle exit and differentiation. Although homeobox protein Msx2 could induce apoptosis of optic vesicle, it is unclear whether Msx2 regulates differentiation and cell fate commitment of retinal progenitor cells (RPCs) to retinal ganglion cells (RGCs). In this study, we show that overexpression of Msx2 transiently suppressed the expression of Cyclin D1 and blocked cell proliferation. Meanwhile, overexpression of Msx2 delayed the expression of RGC-specific differentiation markers (Math5 and Brn3b), which showed that Msx2 could affect the timing of RGCs fate commitment and differentiation by delaying the timing of cell cycle exit of retinal progenitors. These results indicate Msx2 possesses dual regulatory functions in controlling cell cycle progression of retinal RPCs and timing of RGCs differentiation.

  7. 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.

  8. Blood-retinal barrier in hypoxic ischaemic conditions: basic concepts, clinical features and management.

    Science.gov (United States)

    Kaur, C; Foulds, W S; Ling, E A

    2008-11-01

    The blood-retinal barrier (BRB) plays an important role in the homeostatic regulation of the microenvironment in the retina. It consists of inner and outer components, the inner BRB (iBRB) being formed by the tight junctions between neighbouring retinal capillary endothelial cells and the outer barrier (oBRB) by tight junctions between retinal pigment epithelial cells. Astrocytes, Müller cells and pericytes contribute to the proper functioning of the iBRB. In many clinically important conditions including diabetic retinopathy, ischaemic central retinal vein occlusion, and some respiratory diseases, retinal hypoxia results in a breakdown of the iBRB. Disruption of the iBRB associated with increased vascular permeability, results in vasogenic oedema and tissue damage, with consequent adverse effects upon vision. Factors such as enhanced production of vascular endothelial growth factor (VEGF), NO, oxidative stress and inflammation underlie the increased permeability of the iBRB and inhibition of these factors is beneficial. Experimental studies in our laboratory have shown melatonin to be a protective agent for the iBRB in hypoxic conditions. Although oBRB breakdown can occur in conditions such as accelerated hypertension and the toxaemia of pregnancy, both of which are associated with choroidal ischaemia and in age-related macular degeneration (ARMD), and is a feature of exudative (serous) retinal detachment, our studies have shown that the oBRB remains intact in hypoxic/ischaemic conditions. Clinically, anti-VEGF therapy has been shown to improve vision in diabetic maculopathy and in neovascular ARMD. The visual benefit in both conditions appears to arise from the restoration of BRB integrity with a reduction of retinal oedema. PMID:18940262

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

    International Nuclear Information System (INIS)

    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

  10. Adult retinal stem cells revisited.

    OpenAIRE

    Bhatia, B; Singhal, S; Jayaram, H.; Khaw, P T; Limb, G A

    2010-01-01

    Recent advances in retinal stem cell research have raised the possibility that these cells have the potential to be used to repair or regenerate diseased retina. Various cell sources for replacement of retinal neurons have been identified, including embryonic stem cells, the adult ciliary epithelium, adult Müller stem cells and induced pluripotent stem cells (iPS). However, the true stem cell nature of the ciliary epithelium and its possible application in cell therapies has now been question...

  11. Light and inherited retinal degeneration

    OpenAIRE

    Paskowitz, D M; LaVail, M.M.; Duncan, J. L.

    2006-01-01

    Light deprivation has long been considered a potential treatment for patients with inherited retinal degenerative diseases, but no therapeutic benefit has been demonstrated to date. In the few clinical studies that have addressed this issue, the underlying mutations were unknown. Our rapidly expanding knowledge of the genes and mechanisms involved in retinal degeneration have made it possible to reconsider the potential value of light restriction in specific genetic contexts. This review summ...

  12. Cytomegalovirus retinitis mimicking intraocular lymphoma

    Directory of Open Access Journals (Sweden)

    Patrick Gooi

    2008-12-01

    Full Text Available Patrick Gooi1, James Farmer2, Bernard Hurley3, Elliott Brodbaker41Department of Ophthalmology, University of Calgary, Calgary, Alberta, Canada; 2Department of Pathology and Lab Medicine University of Ottawa and The Ottawa Hospital, Ottawa, Ontario, Canada; 3Department of Ophthalmology, University of Ottawa Eye Institute and The Ottawa Hospital, Ottawa, Ontario, Canada; 4Faculty of Medicine, University of Ottawa, Ottawa, Ontario, CanadaAbstract: We present a case of an unusual retinal infiltrate requiring retinal biopsy for definitive diagnosis. A 62-year-old man with treated lymphoma presented with decreased vision in the right eye associated with a white retinal lesion, which extended inferonasally from an edematous disc. Intraocular lymphoma was considered as a diagnosis; thus, the patient was managed with vitrectomy and retinal biopsy. Cytological analysis of the vitreous aspirate could not rule out a lymphoproliferative disorder. The microbial analysis was negative. Histology of the lesion showed extensive necrosis and large cells with prominent nucleoli. To rule out lymphoma, a battery of immunostains was performed and all were negative. However the limited amount of tissue was exhausted in the process. Subsequently, a hematoxylin and eosin (H/E slide was destained, on which a CMV immunostain was performed. This revealed positivity in the nuclei and intranuclear inclusions within the large atypical cells. A diagnosis of CMV retinitis was made. Retinal biopsy may provide a definitive diagnosis and direct patient care toward intravenous gancyclovir in the case of CMV or toward radiation and chemotherapy for intraocular lymphoma. When faced with a limited amount of tissue, destaining regular H/E slides is a possible avenue to performing additional immunohistochemical studies.Keywords: CMV retinitis, retinal biopsy, immunohistochemistry, destaining

  13. An automated vessel segmentation of retinal images using multiscale vesselness

    International Nuclear Information System (INIS)

    The ocular fundus image can provide information on pathological changes caused by local ocular diseases and early signs of certain systemic diseases, such as diabetes and hypertension. Automated analysis and interpretation of fundus images has become a necessary and important diagnostic procedure in ophthalmology. The extraction of blood vessels from retinal images is an important and challenging task in medical analysis and diagnosis. In this paper, we introduce an implementation of the anisotropic diffusion which allows reducing the noise and better preserving small structures like vessels in 2D images. A vessel detection filter, based on a multi-scale vesselness function, is then applied to enhance vascular structures.

  14. Can retinal microtrauma by internal limiting membrane peeling cause retinal angiomatosis proliferans?

    Directory of Open Access Journals (Sweden)

    Pukhraj Rishi

    2011-01-01

    Full Text Available A 32-year-old male presented with decreased vision in right eye since 1 month following trauma with plastic ball. Best-corrected visual acuity (BCVA was 20/160 in right eye and 20/20 in left. Right eye examination revealed angle recession, choroidal rupture, and macular hole. He underwent vitrectomy, internal limiting membrane (ILM peeling, and 14% C3F8 gas injection. After 6 weeks, BCVA was 20/30; fundus showed macular hole closure. Six months after surgery, fundus revealed retinal vascular lesions suggestive of stage I RAP-like lesions; vision was maintained. Clinical findings were confirmed on Video ICGA, FFA, and OCT. The patient was periodically reviewed and lesions were nonprogressive until last follow-up, 13 months after surgery. It seems quite probable that ILM peeling may have caused retinal microtrauma leading to the formation of RAP-like lesions. What factors lead to such an event is as yet not clearly understood. Hence, larger studies with a longer follow-up are warranted to better understand these findings.

  15. Retinal oxygen extraction in humans

    Science.gov (United States)

    Werkmeister, René M.; Schmidl, Doreen; Aschinger, Gerold; Doblhoff-Dier, Veronika; Palkovits, Stefan; Wirth, Magdalena; Garhöfer, Gerhard; Linsenmeier, Robert A.; Leitgeb, Rainer A.; Schmetterer, Leopold

    2015-01-01

    Adequate function of the retina is dependent on proper oxygen supply. In humans, the inner retina is oxygenated via the retinal circulation. We present a method to calculate total retinal oxygen extraction based on measurement of total retinal blood flow using dual-beam bidirectional Doppler optical coherence tomography and measurement of oxygen saturation by spectrophotometry. These measurements were done on 8 healthy subjects while breathing ambient room air and 100% oxygen. Total retinal blood flow was 44.3 ± 9.0 μl/min during baseline and decreased to 18.7 ± 4.2 μl/min during 100% oxygen breathing (P < 0.001) resulting in a pronounced decrease in retinal oxygen extraction from 2.33 ± 0.51 μl(O2)/min to 0.88 ± 0.14 μl(O2)/min during breathing of 100% oxygen. The method presented in this paper may have significant potential to study oxygen metabolism in hypoxic retinal diseases such as diabetic retinopathy. PMID:26503332

  16. 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......-domain optical coherence tomography (OCT) at the baseline visit (ClinicalTrials.gov identifier: NCT01145599). Automated segmentation of the retinal layers of the eyes with subclinical and clinical macular edema was compared with a sample of 31 eyes from diabetic patients with normal OCT and an age......-matched control group of 58 healthy eyes. RESULTS: From the 194 eyes in the study, 62 had subclinical macular edema and 12 had clinical macular edema. The highest increases in retinal thickness (RT) were found in the inner nuclear layer (INL; 33.6% in subclinical macular edema and 81.8% in clinical macular edema...

  17. Concomitant multiple myeloma spectrum diagnosis in a central retinal vein occlusion: a case report and review.

    Science.gov (United States)

    Borgman, Christopher J

    2016-07-01

    Multiple myeloma is a neoplastic plasma-cell disorder resulting from malignant plasma cells in the bone marrow. It can cause a hyperviscosity syndrome secondary to the paraproteinaemia associated with the disease. The increased hyperviscosity can lead to retinal vein occlusions and other ocular problems that may challenge clinicians. In patients with multiple myeloma and hypertension and/or diabetes mellitus, retinal changes appear similar and changes due to one disease or the other may be difficult to determine. A 48-year-old white female presented to the clinic with a complaint of blurry vision in her left eye. A full comprehensive ocular examination revealed a central retinal vein occlusion presumably from the patient's history of hypertension, diabetes mellitus and hypercholesterolaemia. Further bloodwork revealed monoclonal protein in the patient's serum and an increased percentage of plasma cells in the bone marrow. She was diagnosed with monoclonal gammopathy of undetermined significance, part of the multiple myeloma disease spectrum. She was referred to a retinal specialist for initiation of intravitreal injections of anti-vascular endothelial growth factor. Multiple myeloma has been implicated in younger patients as an underlying cause of retinal vein occlusions. Multiple myeloma should be considered as a differential diagnosis in young patients with retinal vein occlusions, even if other risk factors for venous occlusion like hypertension, diabetes mellitus and hypercholesterolaemia are present. Timely referral to the patient's primary care physician and haematologist is important for appropriate treatment and control of underlying systemic conditions. PMID:27079282

  18. Ectopic expression of foxtail millet zip-like gene,SiPf40,in transgenic rice plants causes a pleiotropic phenotype affecting tillering,vascular distribution and root development

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Plant architecture determines grain production in rice(Oryza sativa) and is affected by important agronomic traits such as tillering,plant height,and panicle morphology.Many key genes involved in controlling the initiation and outgrowth of axillary buds,the elongation of stems,and the architecture of inflorescences have been isolated and analyzed.Previous studies have shown that SiPf40,which was identified from a foxtail millet(Setaria italica) immature seed cDNA library,causes extra branches and tillers in SiPf40-transgenic tobacco and foxtail millet,respectively.To reconfirm its function,we generated transgenic rice plants overexpressing SiPf40 under the control of the ubiquitin promoter.SiPf40-overexpressing transgenic plants have a greater tillering number and a wider tiller angle than wild-type plants.Their root architecture is modified by the promotion of lateral root development,and the distribution of xylem and phloem in the vascular bundle is affected.Analysis of hormone levels showed that the ratios of indole-3-acetic acid/zeatin(IAA/ZR) and IAA/gibberellic acid(IAA/GA) decreased in SiPf40-transgenic plants compared with wild-type plants.These findings strongly suggest that SiPf40 plays an important role in plant architecture.

  19. Glucose-6-Phosphate Dehydrogenase Deficiency and Diabetes Mellitus with Severe Retinal Complications in a Sardinian Population, Italy

    OpenAIRE

    Pinna, Antonio; Contini, Emma Luigia; Carru, Ciriaco; Solinas, Giuliana

    2013-01-01

    Background: Glucose-6-Phosphate Dehydrogenase (G6PD) deficiency is one of the most common human genetic abnormalities, with a high prevalence in Sardinia, Italy. Evidence indicates that G6PD-deficient patients are protected against vascular disease. Little is known about the relationship between G6PD deficiency and diabetes mellitus. The purpose of this study was to compare G6PD deficiency prevalence in Sardinian diabetic men with severe retinal vascular complications and in age-matched non-d...

  20. 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.

  1. Quantification of blood vessel calibre in retinal images of multi-ethnic school children using a model based approach.

    Science.gov (United States)

    Fraz, M M; Remagnino, P; Hoppe, A; Rudnicka, A R; Owen, C G; Whincup, P H; Barman, S A

    2013-01-01

    Changes and variation in retinal vessel width are related to vascular risk factors and prospectively related to cardiovascular disease in later life. Hence, assessment of vessel width may be a useful physio-marker and potential predictor of cardiovascular status. However, measurement of vessel calibre from retinal images is a challenging process to automate. This paper proposes an automated system to measure vessel calibre in retinal images, which is demonstrated in images of multi-ethnic school children. The diameter measurement is based on the detection of the centreline pixels from a vessel probability map image, determining the vessel orientation at these pixels, extracting the vessel segments and later using a two-dimensional model, which is optimized to fit various types of intensity profiles of vessel segments. The width is then estimated from parameters of the optimized model. The method is also quantitatively analyzed using monochromatic representations of different colour spaces. The algorithm is evaluated on a recently introduced public database CHASE_DB1, which is a subset of retinal images of multi-ethnic children from the Child Heart and Health Study in England (CHASE) dataset. Moreover, the precise estimation of retinal vascular widths is critical for epidemiologists to identify the risk factors. This work also introduces an interactive software tool for epidemiologists, with which retinal vessel calibre can be precisely marked. PMID:23410507

  2. Preliminary investigation of multispectral retinal tissue oximetry mapping using a hyperspectral retinal camera.

    Science.gov (United States)

    Desjardins, Michèle; Sylvestre, Jean-Philippe; Jafari, Reza; Kulasekara, Susith; Rose, Kalpana; Trussart, Rachel; Arbour, Jean Daniel; Hudson, Chris; Lesage, Frédéric

    2016-05-01

    Oximetry measurement of principal retinal vessels represents a first step towards understanding retinal metabolism, but the technique could be significantly enhanced by spectral imaging of the fundus outside of main vessels. In this study, a recently developed Hyperspectral Retinal Camera was used to measure relative oximetric (SatO2) and total hemoglobin (HbT) maps of the retina, outside of large vessels, in healthy volunteers at baseline (N = 7) and during systemic hypoxia (N = 11), as well as in patients with glaucoma (N = 2). Images of the retina, on a field of view of ∼30°, were acquired between 500 and 600 nm with 2 and 5 nm steps, in under 3 s. The reflectance spectrum from each pixel was fitted to a model having oxy- and deoxyhemoglobin as the main absorbers and scattering modeled by a power law, yielding estimates of relative SatO2 and HbT over the fundus. Average optic nerve head (ONH) saturation over 8 eyes was 68 ± 5%. During systemic hypoxia, mean ONH saturation decreased by 12.5% on average. Upon further development and validation, the relative SatO2 and HbT maps of microvasculature obtained with this imaging system could ultimately contribute to the diagnostic and management of diseases affecting the ONH and retina. PMID:27060375

  3. Retinal detachment in paediatric patients

    International Nuclear Information System (INIS)

    Objective: To assess the causes of retinal detachment in children and the various operative procedures requiring vitreoretinal surgical intervention for the same. Study Design: Case series. Place and Duration of Study: Department of Ophthalmology, Al-Shifa Trust Eye Hospital, Rawalpindi, from January 2006 to May 2009. Methodology: A total of 281 eyes of 258 patients, (aged 0 - 18 years) who underwent vitreo-retinal surgical intervention for retinal detachment were included. Surgical log was searched for the type of retinal detachment and its causes. Frequencies of various interventions done in these patients viz. vitrectomy, scleral buckle, use of tamponading agents, laser photocoagulation and cryotherapy were noted. Results were described as descriptive statistics. Results: Myopia was the cause in 62 (22.1%) and trauma in 51 (18.1%) of the eyes. Total retinal detachment (RD) was treated in 94 (33.5%) eyes, sub total RD in 36 (12.8%), recurrent RD in 32 (11.4%), giant retinal tear in 28 (10%), tractional RD in 15 (5.3%) and exudative RD in 2 (0.7%). Prophylactic laser or cryotherapy was applied in 74 (26.3%) of the eyes. Pars plana vitrectomy (PPV) was carried out in 159 (56.6%) eyes while scleral buckle procedure was done in 129 (45.9%) eyes. Silicon oil was used in 149 (53%), perfluorocarbon liquid in 32 (11.4%) and gas tamponade in 20 (7.1%) eyes. Conclusion: The most common cause of retinal detachment in paediatric patients was myopia, followed by trauma. Total RD was more common as compared to the other types. The most common procedure adopted was pars plana vitrectomy followed by scleral buckle procedure. (author)

  4. Protective effect of magnesium acetyltaurate against endothelin-induced retinal and optic nerve injury.

    Science.gov (United States)

    Arfuzir, N N N; Lambuk, L; Jafri, A J A; Agarwal, R; Iezhitsa, I; Sidek, S; Agarwal, P; Bakar, N S; Kutty, M K; Yusof, A P Md; Krasilnikova, A; Spasov, A; Ozerov, A; Mohd Ismail, N

    2016-06-14

    Vascular dysregulation has long been recognized as an important pathophysiological factor underlying the development of glaucomatous neuropathy. Endothelin-1 (ET1) has been shown to be a key player due to its potent vasoconstrictive properties that result in retinal ischemia and oxidative stress leading to retinal ganglion cell (RGC) apoptosis and optic nerve (ON) damage. In this study we investigated the protective effects of magnesium acetyltaurate (MgAT) against retinal cell apoptosis and ON damage. MgAT was administered intravitreally prior to, along with or after administration of ET1. Seven days post-injection, animals were euthanized and retinae were subjected to morphometric analysis, TUNEL and caspase-3 staining. ON sections were stained with toluidine blue and were graded for neurodegenerative effects. Oxidative stress was also estimated in isolated retinae. Pre-treatment with MgAT significantly lowered ET1-induced retinal cell apoptosis as measured by retinal morphometry and TUNEL staining. This group of animals also showed significantly lesser caspase-3 activation and significantly reduced retinal oxidative stress compared to the animals that received intravitreal injection of only ET1. Additionally, the axonal degeneration in ON was markedly reduced in MgAT pretreated animals. The animals that received MgAT co- or post-treatment with ET1 also showed improvement in all parameters; however, the effects were not as significant as observed in MgAT pretreated animals. The current study showed that the intravitreal pre-treatment with MgAT reduces caspase-3 activation and prevents retinal cell apoptosis and axon loss in ON induced by ET1. This protective effect of ET1 was associated with reduced retinal oxidative stress. PMID:27012609

  5. Carotid ultrasonographic and brain computerized tomographic findings in patients with vascular ocular syndromes

    Energy Technology Data Exchange (ETDEWEB)

    Iwamoto, Toshihiko; Matsushima, Chikage; Shimizu, Souichirou; Takasaki, Masaru; Iwasaki, Takuya; Usui, Masahiko [Tokyo Medical Coll. (Japan)

    2002-02-01

    To clarify the characteristics of cerebrovascular lesions in subtypes of vascular ocular syndrome, including amaurosis fugax (AF), retinal artery occlusion (RAO), and retinal vein occlusion (RVO), 93 patients with vascular ocular syndrome were studied by means of carotid ultrasonography (US) and brain computerized tomography (CT). The subjects comprised 21 patients with AF, 37 with RAO, and 35 with RVO who were sequentially given these diagnoses by the department of ophthalmology. On the basis of US findings, carotid lesions were defined as the presence of plaque or stenotic changes. CT findings were assessed for the presence and distribution of low-density areas (LDAs). Mean age was similar in each group, ranging from 64.5 to 67.4 years. The RAO group had high rates of men, hypertension, and smokers. US showed that the prevalence of carotid lesions ipsilateral to the affected eye was high in the RAO group and that severe stenosis and ulcerated plaque were present in 28.6% of the AF group and 45.9% of the RAO group. On CT examination, cerebral infarctions appeared as LDAs in about 10% of the patients in each group, and the incidence and distribution of LDAs were similar. Of 13 patients with cerebral infarction, only 2 were presumably due to carotid lesions; the others had a variety of causes. The discrepancy between US and CT findings was attributed to the small number of patients with cerebral infarction, since most patients had visual defects as an initial symptom. Our results suggest that extracranial carotid lesions, considered to be a major risk factor for stroke, should be carefully assessed in patients with AF or RAO to prevent further stroke. (author)

  6. Carotid ultrasonographic and brain computerized tomographic findings in patients with vascular ocular syndromes

    International Nuclear Information System (INIS)

    To clarify the characteristics of cerebrovascular lesions in subtypes of vascular ocular syndrome, including amaurosis fugax (AF), retinal artery occlusion (RAO), and retinal vein occlusion (RVO), 93 patients with vascular ocular syndrome were studied by means of carotid ultrasonography (US) and brain computerized tomography (CT). The subjects comprised 21 patients with AF, 37 with RAO, and 35 with RVO who were sequentially given these diagnoses by the department of ophthalmology. On the basis of US findings, carotid lesions were defined as the presence of plaque or stenotic changes. CT findings were assessed for the presence and distribution of low-density areas (LDAs). Mean age was similar in each group, ranging from 64.5 to 67.4 years. The RAO group had high rates of men, hypertension, and smokers. US showed that the prevalence of carotid lesions ipsilateral to the affected eye was high in the RAO group and that severe stenosis and ulcerated plaque were present in 28.6% of the AF group and 45.9% of the RAO group. On CT examination, cerebral infarctions appeared as LDAs in about 10% of the patients in each group, and the incidence and distribution of LDAs were similar. Of 13 patients with cerebral infarction, only 2 were presumably due to carotid lesions; the others had a variety of causes. The discrepancy between US and CT findings was attributed to the small number of patients with cerebral infarction, since most patients had visual defects as an initial symptom. Our results suggest that extracranial carotid lesions, considered to be a major risk factor for stroke, should be carefully assessed in patients with AF or RAO to prevent further stroke. (author)

  7. Temperature controlled retinal photocoagulation

    Science.gov (United States)

    Schlott, Kerstin; Koinzer, Stefan; Baade, Alexander; Birngruber, Reginald; Roider, Johann; Brinkmann, Ralf

    2013-06-01

    Retinal photocoagulation lacks objective dosage in clinical use, thus the commonly applied lesions are too deep and strong, associated with pain reception and the risk of visual field defects and induction of choroidal neovascularisations. Optoacoustics allows real-time non-invasive temperature measurement in the fundus during photocoagulation by applying short probe laser pulses additionally to the treatment radiation, which excite the emission of ultrasonic waves. Due to the temperature dependence of the Grüneisen parameter, the amplitudes of the ultrasonic waves can be used to derive the temperature of the absorbing tissue. By measuring the temperatures in real-time and automatically controlling the irradiation by feedback to the treatment laser, the strength of the lesions can be defined. Different characteristic functions for the time and temperature dependent lesion sizes were used as rating curves for the treatment laser, stopping the irradiation automatically after a desired lesion size is achieved. The automatically produced lesion sizes are widely independent of the adjusted treatment laser power and individual absorption. This study was performed on anaesthetized rabbits and is a step towards a clinical trial with automatically controlled photocoagulation.

  8. DNA Damage and Repair in Vascular Disease.

    Science.gov (United States)

    Uryga, Anna; Gray, Kelly; Bennett, Martin

    2016-01-01

    DNA damage affecting both genomic and mitochondrial DNA is present in a variety of both inherited and acquired vascular diseases. Multiple cell types show persistent DNA damage and a range of lesions. In turn, DNA damage activates a variety of DNA repair mechanisms, many of which are activated in vascular disease. Such DNA repair mechanisms either stall the cell cycle to allow repair to occur or trigger apoptosis or cell senescence to prevent propagation of damaged DNA. Recent evidence has indicated that DNA damage occurs early, is progressive, and is sufficient to impair function of cells composing the vascular wall. The consequences of persistent genomic and mitochondrial DNA damage, including inflammation, cell senescence, and apoptosis, are present in vascular disease. DNA damage can thus directly cause vascular disease, opening up new possibilities for both prevention and treatment. We review the evidence for and the causes, types, and consequences of DNA damage in vascular disease. PMID:26442438

  9. Risk Factors for Giant Retinal Tears

    Directory of Open Access Journals (Sweden)

    Morteza Mehdizadeh

    2010-01-01

    Full Text Available Purpose: To evaluate the risk factors associated with giant retinal tears. Methods: This retrospective study was performed on medical records of 150 patients who had undergone retinal detachment surgery. Age, sex, history of trauma, lens status (phakic, pseudophakic, or aphakic, and high myopia were evaluated in association with giant retinal tears. Results: Of 150 patients with retinal detachments, 99 subjects (66% were older than 30 years while 51 (34% were 30 years of age or younger. Overall, 26 (17.3% patients had giant retinal tears. Controlling for all variables, only age had a significant correlation with giant retinal tears. Each year of advancing age was associated with a 6% decrease in the incidence of giant retinal tears. Conclusion: Young age is a significant risk factor for development of giant retinal tears.

  10. Intravitreal steroids for the treatment of retinal diseases.

    Science.gov (United States)

    Sarao, Valentina; Veritti, Daniele; Boscia, Francesco; Lanzetta, Paolo

    2014-01-01

    Diabetic macular edema (DME), pseudophakic cystoid macular edema (CME), age-related macular degeneration (AMD), retinal vascular occlusion (RVO), and uveitis are ocular conditions related to severe visual impairment worldwide. Corticosteroids have been widely used in the treatment of these retinal diseases, due to their well-known antiangiogenic, antiedematous, and anti-inflammatory properties. Intravitreal steroids have emerged as novel and essential tools in the ophthalmologist's armamentarium, allowing for maximization of drug efficacy and limited risk of systemic side effects. Recent advances in ocular drug delivery methods led to the development of intraocular implants, which help to provide prolonged treatment with controlled drug release. Moreover, they may add some potential advantages over traditional intraocular injections by delivering certain rates of drug directly to the site of action, amplifying the drug's half-life, contributing in the minimization of peak plasma levels of the drug, and avoiding the side effects associated with repeated intravitreal injections. The purpose of this review is to provide an update on the use of intravitreal steroids as a treatment option for a variety of retinal diseases and to review the current literature considering their properties, safety, and adverse events. PMID:24526927

  11. Intravitreal Steroids for the Treatment of Retinal Diseases

    Directory of Open Access Journals (Sweden)

    Valentina Sarao

    2014-01-01

    Full Text Available Diabetic macular edema (DME, pseudophakic cystoid macular edema (CME, age-related macular degeneration (AMD, retinal vascular occlusion (RVO, and uveitis are ocular conditions related to severe visual impairment worldwide. Corticosteroids have been widely used in the treatment of these retinal diseases, due to their well-known antiangiogenic, antiedematous, and anti-inflammatory properties. Intravitreal steroids have emerged as novel and essential tools in the ophthalmologist’s armamentarium, allowing for maximization of drug efficacy and limited risk of systemic side effects. Recent advances in ocular drug delivery methods led to the development of intraocular implants, which help to provide prolonged treatment with controlled drug release. Moreover, they may add some potential advantages over traditional intraocular injections by delivering certain rates of drug directly to the site of action, amplifying the drug’s half-life, contributing in the minimization of peak plasma levels of the drug, and avoiding the side effects associated with repeated intravitreal injections. The purpose of this review is to provide an update on the use of intravitreal steroids as a treatment option for a variety of retinal diseases and to review the current literature considering their properties, safety, and adverse events.

  12. Vascular Dysfunction in Diabetes and Glaucoma: A Complex Relationship Reviewed.

    Science.gov (United States)

    Gerber, Austin L; Harris, Alon; Siesky, Brent; Lee, Eric; Schaab, Tara J; Huck, Andrew; Amireskandari, Annahita

    2015-08-01

    Open-angle glaucoma (OAG) is a multifactorial disease characterized by progressive retinal ganglion cell death and visual field loss. Intraocular pressure, ocular perfusion pressure, and systemic vascular irregularities have all been identified as contributing factors for glaucoma onset and progression. Focal and systemic vascular abnormalities have also been well documented in diabetic patients. The relationship between diabetes mellitus and OAG remains enigmatic in the literature. As the pathogenesis of both diabetes mellitus and OAG involves compromised vascular regulation, this review was undertaken to further investigate their precise relationship. A literature review of published population-based studies was performed, with a focus on studies regarding blood flow abnormalities. Although current studies support the role of vascular contributions to both diseases, the association between glaucoma and diabetes yields contrasting results. PMID:25264988

  13. Risk Factors for Giant Retinal Tears

    OpenAIRE

    Morteza Mehdizadeh; Mehrdad Afarid; Mohammad Shabanpour Haqiqi

    2010-01-01

    Purpose: To evaluate the risk factors associated with giant retinal tears. Methods: This retrospective study was performed on medical records of 150 patients who had undergone retinal detachment surgery. Age, sex, history of trauma, lens status (phakic, pseudophakic, or aphakic), and high myopia were evaluated in association with giant retinal tears. Results: Of 150 patients with retinal detachments, 99 subjects (66%) were older than 30 years while 51 (34%) were 30 years of age or you...

  14. Risk Factors for Giant Retinal Tears

    OpenAIRE

    Mehdizadeh, Morteza; Afarid, Mehrdad; Haqiqi, Mohammad Shabanpour

    2010-01-01

    Purpose To evaluate the risk factors associated with giant retinal tears. Methods This retrospective study was performed on medical records of 150 patients who had undergone retinal detachment surgery. Age, sex, history of trauma, lens status (phakic, pseudophakic, or aphakic), and high myopia were evaluated in association with giant retinal tears. Results Of 150 patients with retinal detachments, 99 subjects (66%) were older than 30 years while 51 (34%) were 30 years of age or younger. Overa...

  15. 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;

    blood pressure was 152/84mmHg. Retinal arterial and venous saturation was 96.7% and 67.4%, respectively. Patients in Group 1 and 2 did not differ in baseline retinal arterial and venous oxygen saturation, number of laser spots delivered, total laser energy delivered, or change in retinal arterial oxygen...... 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.......®; OD-OS GmbH, Berlin, Germany). At follow-up, WFA was used to evaluate PDR activity and patients were categorized into two groups: progression (Group 1, n=10) or stability/regression of PDR (Group 2, n=29). Retinal oximetry measurements were performed on optic disc centered images using the in...

  16. Long-term control of CMV retinitis in a patient with idiopathic CD4+ T lymphocytopenia.

    Science.gov (United States)

    Yashiro, Shigeko; Fujino, Yujiro; Tachikawa, Natsuo; Inamochi, Kazuya; Oka, Shinichi

    2013-04-01

    Cytomegalovirus (CMV) retinitis with idiopathic CD4(+) T lymphocytopenia (ICL) is rare and difficult to control. We report a first case for long-term control of CMV retinitis with ICL using interleukin-2 (IL-2) therapy and succeeded in discontinuation of anti-CMV therapy. A 49-year-old Japanese woman was diagnosed with ICL based on low CD4(+) count (72/μl), negative for HIV-1 and -2 antibodies, and absence of any defined immunodeficiency diseases or immunosuppressive therapy. PCR test of the aqueous humor in the right eye was suggestive of CMV retinitis. She was treated with systemic ganciclovir, but after several relapses of CMV retinitis, rhegmatogenous retinal detachment appeared in the right eye and she became blind in that eye. Three years later, she developed CMV retinitis in the left eye. Although she received systemic and focal anti-CMV treatments, the retinitis showed no improvement. Finally, retinal detachment occurred, and she underwent vitrectomy. IL-2 was injected to increase CD4(+) counts. Because of hyperpyrexia, blepharedema, central scotoma, and color anomaly, we changed to low-dose IL-2 therapy with no side effects. Finally, we succeeded in increasing the CD4(+) count to more than 200/μl after discontinuation of low-dose IL-2 therapy. CMV retinitis never recurred after discontinuation of anti-CMV therapy, with good visual acuity of 20/20 in the left eye. She developed blindness of the first affected right eye, whereas the visual acuity of the left eye remains excellent more than 12 years after the onset of CMV retinitis through the combined use of anti-CMV therapy, IL-2 therapy, and vitrectomy. PMID:22935818

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

    Directory of Open Access Journals (Sweden)

    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

  18. Endothelium Expression of Bcl-2 Is Essential for Normal and Pathological Ocular Vascularization

    OpenAIRE

    Ismail S Zaitoun; Johnson, Ryan P.; Jamali, Nasim; Almomani, Reem; Wang, Shoujian; Sheibani, Nader; Sorenson, Christine M.

    2015-01-01

    Bcl–2 is an anti-apoptotic protein with important roles in vascular homeostasis and angiogenesis. Mice globally lacking Bcl–2 (Bcl–2 -/-) are small in stature and succumb to renal failure shortly after weaning as a result of renal hypoplasia/cystic dysplasia. We have shown that Bcl–2 -/- mice displayed attenuated retinal vascular development and neovascularization. In vitro studies indicated that in addition to modulating apoptosis, Bcl–2 expression also impacts endothelial and epithelial cel...

  19. Retinal Optical Coherence Tomography Imaging

    Science.gov (United States)

    Drexler, Wolfgang; Fujimoto, James G.

    The eye is essentially transparent, transmitting light with only minimal optical attenuation and scattering providing easy optical access to the anterior segment as well as the retina. For this reason, ophthalmic and especially retinal imaging has been not only the first but also most successful clinical application for optical coherence tomography (OCT). This chapter focuses on the development of OCT technology for retinal imaging. OCT has significantly improved the potential for early diagnosis, understanding of retinal disease pathogenesis, as well as monitoring disease progression and response to therapy. Development of ultrabroad bandwidth light sources and high-speed detection techniques has enabled significant improvements in ophthalmic OCT imaging performance, demonstrating the potential of three-dimensional, ultrahigh-resolution OCT (UHR OCT) to perform noninvasive optical biopsy of the living human retina, i.e., the in vivo visualization of microstructural, intraretinal morphology in situ approaching the resolution of conventional histopathology. Significant improvements in axial resolution and speed not only enable three-dimensional rendering of retinal volumes but also high-definition, two-dimensional tomograms, topographic thickness maps of all major intraretinal layers, as well as volumetric quantification of pathologic intraretinal changes. These advances in OCT technology have also been successfully applied in several animal models of retinal pathologies. The development of light sources emitting at alternative wavelengths, e.g., around #1,060 nm, not only enabled three-dimensional OCT imaging with enhanced choroidal visualization but also improved OCT performance in cataract patients due to reduced scattering losses in this wavelength region. Adaptive optics using deformable mirror technology, with unique high stroke to correct higher-order ocular aberrations, with specially designed optics to compensate chromatic aberration of the human eye, in

  20. Suitability of UK Biobank Retinal Images for Automatic Analysis of Morphometric Properties of the Vasculature.

    Directory of Open Access Journals (Sweden)

    Thomas J MacGillivray

    Full Text Available To assess the suitability of retinal images held in the UK Biobank--the largest retinal data repository in a prospective population-based cohort--for computer assisted vascular morphometry, generating measures that are commonly investigated as candidate biomarkers of systemic disease.Non-mydriatic fundus images from both eyes of 2,690 participants--people with a self-reported history of myocardial infarction (n=1,345 and a matched control group (n=1,345--were analysed using VAMPIRE software. These images were drawn from those of 68,554 UK Biobank participants who underwent retinal imaging at recruitment. Four operators were trained in the use of the software to measure retinal vascular tortuosity and bifurcation geometry.Total operator time was approximately 360 hours (4 minutes per image. 2,252 (84% of participants had at least one image of sufficient quality for the software to process, i.e. there was sufficient detection of retinal vessels in the image by the software to attempt the measurement of the target parameters. 1,604 (60% of participants had an image of at least one eye that was adequately analysed by the software, i.e. the measurement protocol was successfully completed. Increasing age was associated with a reduced proportion of images that could be processed (p=0.0004 and analysed (p<0.0001. Cases exhibited more acute arteriolar branching angles (p=0.02 as well as lower arteriolar and venular tortuosity (p<0.0001.A proportion of the retinal images in UK Biobank are of insufficient quality for automated analysis. However, the large size of the UK Biobank means that tens of thousands of images are available and suitable for computational analysis. Parametric information measured from the retinas of participants with suspected cardiovascular disease was significantly different to that measured from a matched control group.

  1. 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

  2. IGFBP3 suppresses retinopathy through suppression of oxygen-induced vessel loss and promotion of vascular regrowth

    OpenAIRE

    Lofqvist, Chatarina; Chen, Jing; Connor, Kip M.; Smith, Alexandra C. H.; Aderman, Christopher M.; Liu, Nan; Pintar, John E.; Ludwig, Thomas; Hellstrom, Ann; Smith, Lois E. H.

    2007-01-01

    Vessel loss precipitates many diseases. In particular, vessel loss resulting in hypoxia induces retinal neovascularization in diabetic retinopathy and in retinopathy of prematurity (ROP), major causes of blindness. Here we define insulin-like growth factor binding protein-3 (IGFBP3) as a new modulator of vascular survival and regrowth in oxygen-induced retinopathy. In IGFBP3-deficient mice, there was a dose-dependent increase in oxygen-induced retinal vessel loss. Subsequent to oxygen-induced...

  3. 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.

  4. 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.

  5. Retinal Targets ALDH Positive Cancer Stem Cell and Alters the Phenotype of Highly Metastatic Osteosarcoma Cells

    Directory of Open Access Journals (Sweden)

    Xiaodong Mu

    2015-01-01

    Full Text Available Aldehyde dehydrogenase (ALDH is a cancer stem cell marker. Retinoic acid has antitumor properties, including the induction of apoptosis and inhibition of proliferation. Retinal, the precursor of retinoic acid, can be oxidized to retinoic acid by dehydrogenases, including ALDH. We hypothesized that retinal could potentially be transformed to retinoic acid with higher efficiency by cancer stem cells, due to the higher ALDH activity. We previously observed that ALDH activity is greater in highly metastatic K7M2 osteosarcoma (OS cells than in nonmetastatic K12 OS cells. We also demonstrated that ALDH activity correlates with clinical metastases in bone sarcoma patients, suggesting that ALDH may be a therapeutic target specific to cells with high metastatic potential. Our current results demonstrated that retinal preferentially affected the phenotypes of ALDH-high K7M2 cells in contrast to ALDH-low K12 cells, which could be mediated by the more efficient transformation of retinal to retinoic acid by ALDH in K7M2 cells. Retinal treatment of highly metastatic K7M2 cells decreased their proliferation, invasion capacity, and resistance to oxidative stress. Retinal altered the expression of metastasis-related genes. These observations indicate that retinal may be used to specifically target metastatic cancer stem cells in OS.

  6. Outer retinal tubulation in diabetic macular edema following anti-VEGF treatment

    OpenAIRE

    Al-Halafi, Ali M.

    2015-01-01

    Background To address the presence and features of outer retinal tubulation (ORT) found in diabetic macular edema (DME) treated with anti-vascular endothelial growth factor (anti-VEGF) and to differentiate between ORT and cystoid DME, which have different plans of management. Methods This was a retrospective review of a total of 514 patients investigated with spectral domain optical coherence tomography (OCT) in patients with diabetic macular edema treated with anti-VEGF. ORT was seen in 12 e...

  7. A MATLAB Based Algorithm Design for New Structural Feature of Retinal Image Vasculature Pattern

    Directory of Open Access Journals (Sweden)

    Udaya Kumar Naluguru

    2013-01-01

    Full Text Available In this paper we illustrate the different point types in retinal images. The bifurcation structure is composed of a master bifurcation point and three connected neighbors. In this paper we present the illustration of featured based method, which is explained in detail and further image registration results are also discussed in detail. The advantage of the proposed structure-matching approach is the ability to handle translation, rotation and scaling with the available vascular trees of image pairs.

  8. Spectral domain optical coherence tomography features of multiple subfoveal retinal pigment epithelial tears after intravitreal bevacizumab

    Directory of Open Access Journals (Sweden)

    Chalam Kakarla

    2011-01-01

    Full Text Available Retinal pigment epithelial (RPE tear has been described to occur spontaneously, after laser photocoagulation and in recent times, after intravitreal injection of anti-vascular endothelial growth factor (VEGF agents. In the latter case, the rapid contraction of the choroidal vascular membrane underneath a serous RPE detachment is believed to be the underlying cause. Preservation of good visual acuity after the occurrence of RPE tear with continued use of intravitreal VEGF agents has been reported. In this case report, we describe the occurrence of multiple RPE tears with the use of intravitreal bevacizumab and also correlate the preservation of visual acuity with features seen on spectral domain optical coherence tomography.

  9. MicroRNA-126 contributes to Niaspan treatment induced vascular restoration after diabetic retinopathy.

    Science.gov (United States)

    Wang, Yang; Yan, Hua

    2016-01-01

    Diabetic retinopathy (DR) is a serious microvascular complication of diabetes and a major cause of blindness in the developing world. Early diabetic retinopathy is characterized by a loss of pericytes and vascular endothelial cells, a breakdown of the blood-retinal barrier, vascular dysfunction and vascular-neuroinflammation. However, optimal treatment options and related mechanisms are still unclear. MicroRNA-126 (miR-126) plays a potential role in the pathogenesis in DR, which may regulate VEGF, Ang-1 and VCAM-1 expressions. This study investigated the therapeutic effects and mechanisms of Niaspan treatment of DR in diabetes (DM) rats. DM rats exhibits significantly decreased miR-126 and tight junction Claudin-5/Occludin/ZO-1 genes expression, and increased Blood retinal-barrier (BRB) breakdown, retinal apoptosis and VEGF/VEGFR, as well as VCAM-1/CD45 expressions in the retina compared to normal control group. Niaspan treatment significantly improved clinical and histopathological outcomes; decreased the expressions of VEGF/VEGFR, VCAM-1/CD45, apoptosis and BRB breakdown, significantly increased tight junction proteins and Ang-1/Tie-2 expressions, as well as increased retinal miR-126 expression compared to non-treatment diabetic rats. These data are the first to show that Niaspan treatment ameliorates DR through its repair vascular and inhibits inflammatory effects, and also suggest that the miR-126 pathway may contribute to Niaspan treatment induced benefit effects. PMID:27225425

  10. 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

  11. Retinitis Pigmentosa and Education Issues

    Science.gov (United States)

    Brown, Thomas J.

    2005-01-01

    Retinitis Pigmentosa includes a number of inherited diseases which usually result in blindness. The disease is progressive in nature and begins with the deterioration of cells in the eye responsible for peripheral vision. As the condition worsens there is a gradual loss of peripheral vision and night blindness. Proper educational planning requires…

  12. Confocal scanning laser ophthalmoscopic imaging resolution of secondary retinal effects induced by laser radiation

    Science.gov (United States)

    Zwick, Harry; Lund, David J.; Stuck, Bruce E.; Zuclich, Joseph A.; Elliot, Rowe; Schuschereba, Steven T.; Gagliano, Donald A.; Belkin, M.; Glickman, Randolph D.

    1996-02-01

    We have evaluated secondary laser induced retinal effects in non-human primates with a Rodenstock confocal scanning laser ophthalmoscope. A small eye animal model, the Garter snake, was employed to evaluate confocal numerical aperture effects in imaging laser retinal damage in small eyes vs. large eyes. Results demonstrate that the confocal image resolution in the Rhesus monkey eye is sufficient to differentiate deep retinal scar formation from retinal nerve fiber layer (NFL) damage and to estimate the depth of the NFL damage. The best comparison with histological depth was obtained for the snake retina, yielding a ratio close to 1:1 compared to 2:1 for the Rhesus. Resolution in the Garter snake allows imaging the photoreceptor matrix and therefore, evaluation of the interrelationship between the primary damage site (posterior retina), the photoreceptor matrix, and secondary sites in the anterior retina such as the NFL and the epiretinal vascular system. Alterations in both the retinal NFL and epiretinal blood flow rate were observed within several minutes post Argon laser exposure. Unique aspects of the snake eye such as high tissue transparency and inherently high contrast cellular structures, contribute to the confocal image quality. Such factors may be nearly comparable in primate eyes suggesting that depth of resolution can be improved by smaller confocal apertures and more sensitive signal processing techniques.

  13. Glio-vascular modifications caused by Aquaporin-4 deletion in the mouse retina.

    Science.gov (United States)

    Nicchia, Grazia Paola; Pisani, Francesco; Simone, Laura; Cibelli, Antonio; Mola, Maria Grazia; Dal Monte, Massimo; Frigeri, Antonio; Bagnoli, Paola; Svelto, Maria

    2016-05-01

    Aquaporin-4 (AQP4) is the Central Nervous System water channel highly expressed at the perivascular glial domain. In the retina, two types of AQP4 expressing glial cells take part in the blood-retinal barrier (BRB), astrocytes and Müller cells. The aim of the present study is to investigate the effect of AQP4 deletion on the retinal vasculature by looking at typical pathological hallmark such as BRB dysfunction and gliotic condition. AQP4 dependent BRB properties were evaluated by measuring the number of extravasations in WT and AQP4 KO retinas by Evans blue injection assay. AQP4 deletion did not affect the retinal vasculature, as assessed by Isolectin B4 staining, but caused BRB impairment to the deep plexus capillaries while the superficial and intermediate capillaries were not compromised. To investigate for gliotic responses caused by AQP4 deletion, Müller cells and astrocytes were analysed by immunofluorescence and western blot, using the Müller cell marker Glutamine Synthetase (GS) and the astrocyte marker GFAP. While GS expression was not altered in AQP4 KO retinas, a strong GFAP upregulation was found at the level of AQP4 KO astrocytes at the superficial plexus and not at Müller cells at the intermediate and deep plexi. These data, together with the upregulation of inflammatory markers (TNF-α, IL-6, IL-1β and ICAM-1) in AQP4 KO retinas indicated AQP4 deletion as responsible for a gliotic phenotype. Interestingly, no GFAP altered expression was found in AQP4 siRNA treated astrocyte primary cultures. All together these results indicate that AQP4 deletion is directly responsible for BRB dysfunction and gliotic condition in the mouse retina. The selective activation of glial cells at the primary plexus suggests that different regulatory elements control the reaction of astrocytes and Müller cells. Finally, GFAP upregulation is strictly linked to gliovascular crosstalk, as it is absent in astrocytes in culture. This study is useful to understand the role

  14. Learning about Retinitis Pigmentosa

    Science.gov (United States)

    ... sighted individuals encounter when entering a dark movie theatre on a bright, sunny day. However, patients with ... the same defective gene. The chances of a child being affected is one in four. This means ...

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

    OpenAIRE

    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 mutation may show a striking phenotypic variability. Best vitelliform macular dystrophy, caused by mutations in the BEST1 gene, and retinal dystrophies caused by peripherin/RDS gene mutations, are g...

  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. Coronary-Heart-Disease-Associated Genetic Variant at the COL4A1/COL4A2 Locus Affects COL4A1/COL4A2 Expression, Vascular Cell Survival, Atherosclerotic Plaque Stability and Risk of Myocardial Infarction.

    Science.gov (United States)

    Yang, Wei; Ng, Fu Liang; Chan, Kenneth; Pu, Xiangyuan; Poston, Robin N; Ren, Meixia; An, Weiwei; Zhang, Ruoxin; Wu, Jingchun; Yan, Shunying; Situ, Haiteng; He, Xinjie; Chen, Yequn; Tan, Xuerui; Xiao, Qingzhong; Tucker, Arthur T; Caulfield, Mark J; Ye, Shu

    2016-07-01

    Genome-wide association studies have revealed an association between coronary heart disease (CHD) and genetic variation on chromosome 13q34, with the lead single nucleotide polymorphism rs4773144 residing in the COL4A2 gene in this genomic region. We investigated the functional effects of this genetic variant. Analyses of primary cultures of vascular smooth muscle cells (SMCs) and endothelial cells (ECs) from different individuals showed a difference between rs4773144 genotypes in COL4A2 and COL4A1 expression levels, being lowest in the G/G genotype, intermediate in A/G and highest in A/A. Chromatin immunoprecipitation followed by allelic imbalance assays of primary cultures of SMCs and ECs that were of the A/G genotype revealed that the G allele had lower transcriptional activity than the A allele. Electrophoretic mobility shift assays and luciferase reporter gene assays showed that a short DNA sequence encompassing the rs4773144 site interacted with a nuclear protein, with lower efficiency for the G allele, and that the G allele sequence had lower activity in driving reporter gene expression. Analyses of cultured SMCs from different individuals demonstrated that cells of the G/G genotype had higher apoptosis rates. Immunohistochemical and histological examinations of ex vivo atherosclerotic coronary arteries from different individuals disclosed that atherosclerotic plaques with the G/G genotype had lower collagen IV abundance and thinner fibrous cap, a hallmark of unstable, rupture-prone plaques. A study of a cohort of patients with angiographically documented coronary artery disease showed that patients of the G/G genotype had higher rates of myocardial infarction, a phenotype often caused by plaque rupture. These results indicate that the CHD-related genetic variant at the COL4A2 locus affects COL4A2/COL4A1 expression, SMC survival, and atherosclerotic plaque stability, providing a mechanistic explanation for the association between the genetic variant and CHD

  18. Collagen vascular disease

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/001223.htm Collagen vascular disease To use the sharing features on this page, ... were previously said to have "connective tissue" or "collagen vascular" disease. We now have names for many of many ...

  19. Heart and vascular services

    Science.gov (United States)

    ... branch of medicine that focuses on the cardiovascular system. ... Circulatory system; Vascular system; Cardiovascular system ... to diagnose, monitor or treat diseases of the circulatory and vascular system include: Cardiac CT for calcium scoring Cardiac MRI ...

  20. 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

    OpenAIRE

    Shimizu, Kazuhiro; Yamamoto, Tomoyuki; Shirai, Kohji

    2016-01-01

    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 ...

  1. Novel mutations in two Saudi patients with congenital retinal dystrophy

    OpenAIRE

    Leen Abu Safieh; Humoud M Al-Otaibi; 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...

  2. Contrast-based sensorless adaptive optics for retinal imaging

    OpenAIRE

    Zhou, Xiaolin; Bedggood, Phillip; Bui, Bang; Nguyen, Christine T. O.; He, Zheng; Metha, Andrew

    2015-01-01

    Conventional adaptive optics ophthalmoscopes use wavefront sensing methods to characterize ocular aberrations for real-time correction. However, there are important situations in which the wavefront sensing step is susceptible to difficulties that affect the accuracy of the correction. To circumvent these, wavefront sensorless adaptive optics (or non-wavefront sensing AO; NS-AO) imaging has recently been developed and has been applied to point-scanning based retinal imaging modalities. In thi...

  3. 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.

  4. Vasoproliferative retinal tumor. Report of two cases

    International Nuclear Information System (INIS)

    Vasoproliferative retinal tumor is a rare and benign condition that presents as an exudative lesion in the peripheral retina. The lesion can be classified in primary (idiopathic) or secondary to other ocular processes. Therapeutic options include observation, cryotherapy, laser photocoagulation, surgical removal by pars plana vitrectomy, photodynamic therapy and epiescleral brachytheraphy with radio-active isotopes associated or not to the use of anti-angiogenic or anti-inflammatory drugs. The selection of a particular management modality depends on the type of case. Two female patients affected with this condition were presented; the most important characteristics in their clinical pictures, as well as the results of other tests as retinography, fluorescent and ICG angiography and echography were described. The management and the therapeutical and evolutive course of both patients were also discussed

  5. Bilateral retinal cyst accompanying with renal and thyroidal multiorgan cyst

    OpenAIRE

    Amber Şenel; Rıfat Rasier; Alper Şengül; Erdal Yüzbaşıoğlu; Özgür Artunay; Halil Bahçecioğlu

    2011-01-01

    Although retinal cysts are commonly seen in von Hippel Lindau syndrome, bilateral retinal cysts can occasionally appear unrelated to this syndrome. Retinal cysts can be confused with retinal tumours and infectious diseases of retina. In this report we represent a patient demonstrating bilateral retinal cyst accompanying with renal and thyroidal multiorgan cysts without Von-Hippel Lindau syndrome.

  6. High quality optical microangiography of ocular microcirculation and measurement of total retinal blood flow in mouse eye

    Science.gov (United States)

    Zhi, Zhongwei; Yin, Xin; Dziennis, Suzan; Alpers, Charles E.; Wang, Ruikang K.

    2013-03-01

    Visualization and measurement of retinal blood flow (RBF) is important to the diagnosis and management of different eye diseases, including diabetic retinopathy. Optical microangiography (OMAG) is developed for generating 3D dynamic microcirculation image and later refined into ultra-high sensitive OMAG (UHS-OMAG) for true capillary vessels imaging. Here, we present the application of OMAG imaging technique for visualization of depth-resolved vascular network within retina and choroid as well as measurement of total retinal blood flow in mice. A fast speed spectral domain OCT imaging system at 820nm with a line scan rate of 140 kHz was developed to image mouse posterior eye. By applying UHS-OMAG scanning protocol and processing algorithm, we achieved true capillary level imaging of retina and choroid vasculature in mouse eye. The vascular pattern within different retinal layers and choroid was presented. An en face Doppler OCT approach [1] without knowing Doppler angle was adopted for the measurement of total retinal blood flow. The axial blood flow velocity is measured in an en face plane by raster scanning and the flow is calculated by integrating over the vessel area of the central retinal artery.

  7. Altered astrocyte morphology and vascular development in dystrophin-Dp71-null mice.

    Science.gov (United States)

    Giocanti-Auregan, Audrey; Vacca, Ophélie; Bénard, Romain; Cao, Sijia; Siqueiros, Lourdes; Montañez, Cecilia; Paques, Michel; Sahel, José-Alain; Sennlaub, Florian; Guillonneau, Xavier; Rendon, Alvaro; Tadayoni, Ramin

    2016-05-01

    Understanding retinal vascular development is crucial because many retinal vascular diseases such as diabetic retinopathy (in adults) or retinopathy of prematurity (in children) are among the leading causes of blindness. Given the localization of the protein Dp71 around the retinal vessels in adult mice and its role in maintaining retinal homeostasis, the aim of this study was to determine if Dp71 was involved in astrocyte and vascular development regulation. An experimental study in mouse retinas was conducted. Using a dual immunolabeling with antibodies to Dp71 and anti-GFAP for astrocytes on retinal sections and isolated astrocytes, it was found that Dp71 was expressed in wild-type (WT) mouse astrocytes from early developmental stages to adult stage. In Dp71-null mice, a reduction in GFAP-immunopositive astrocytes was observed as early as postnatal day 6 (P6) compared with WT mice. Using real-time PCR, it was showed that Dp71 mRNA was stable between P1 and P6, in parallel with post-natal vascular development. Regarding morphology in Dp71-null and WT mice, a significant decrease in overall astrocyte process number in Dp71-null retinas at P6 to adult age was found. Using fluorescence-conjugated isolectin Griffonia simplicifolia on whole mount retinas, subsequent delay of developing vascular network at the same age in Dp71-null mice was found. An evidence that the Dystrophin Dp71, a membrane-associated cytoskeletal protein and one of the smaller Duchenne muscular dystrophy gene products, regulates astrocyte morphology and density and is associated with subsequent normal blood vessel development was provided. GLIA 2016;64:716-729. PMID:26711882

  8. How to Prevent Vascular Disease

    Science.gov (United States)

    ... our CEO Board of Directors Scientific Advisory Board History of Vascular Cures Impact Contact Us Vascular Disease What is Vascular Disease? Education and Awareness Vascular Diseases Abdominal Aortic Aneurysm Aortic ...

  9. NADPH Oxidases in Vascular Pathology

    OpenAIRE

    Konior, Anna; Schramm, Agata; Czesnikiewicz-Guzik, Marta; Tomasz J. Guzik

    2014-01-01

    Significance: Reactive oxygen species (ROS) play a critical role in vascular disease. While there are many possible sources of ROS, nicotinamide adenine dinucleotide phosphate (NADPH) oxidases play a central role. They are a source of “kindling radicals,” which affect other enzymes, such as nitric oxide synthase endothelial nitric oxide synthase or xanthine oxidase. This is important, as risk factors for atherosclerosis (hypertension, diabetes, hypercholesterolemia, and smoking) regulate the ...

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

    International Nuclear Information System (INIS)

    Highlights: ► Zic transcription factors expressed early retinal progenitor cells. ► Zics sustain proliferation activity of retinal progenitor cells. ► Overexpression of Zic in retinal progenitors perturbed rod differentiation. ► 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.

  11. 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.

  12. Automatic diagnosis of retinal diseases from color retinal images

    OpenAIRE

    Jayanthi, D.; N. Devi; 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...

  13. 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.

  14. Retinal Image Preprocessing: Background and Noise Segmentation

    Directory of Open Access Journals (Sweden)

    Usman Akram

    2012-07-01

    Full Text Available Retinal images are used for the automated screening and diagnosis of diabetic retinopathy. The retinal image quality must be improved for the detection of features and abnormalities and for this purpose preprocessing of retinal images is vital. In this paper, we present a novel automated approach for preprocessing of colored retinal images. The proposed technique improves the quality of input retinal image by separating the background and noisy area from the overall image. It contains coarse segmentation and fine segmentation. Standard retinal images databases Diaretdb0, Diaretdb1, DRIVE and STARE are used to test the validation of our preprocessing technique. The experimental results show the validity of proposed preprocessing technique.

  15. Inner Retinal Oxygen Delivery and Metabolism in Streptozotocin Diabetic Rats

    OpenAIRE

    Wanek, Justin; Teng, Pang-yu; Blair, Norman P.; Shahidi, Mahnaz

    2014-01-01

    Measurements of inner retinal oxygen delivery and oxygen metabolism in streptozotocin diabetic rats indicate that oxygen supplied by the retinal circulation and consumed by the inner retinal tissue were not altered within 6 weeks of diabetes.

  16. Spectrophotometric retinal oximetry in pigs

    DEFF Research Database (Denmark)

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

    2013-01-01

    PURPOSE: To assess the validity of spectrophotometric retinal oximetry, by comparison to blood gas analysis and intra-vitreal measurements of partial pressure of oxygen (pO2). METHODS: Female domestic pigs were used for all experiments (n=8). Oxygen fraction in inspired air was changed using a......, 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......-measurements in three pigs. This relationship was approximately linear (R(2) = 0.45, p = 0.04). CONCLUSIONS: Non-invasive spectrophotometric oximetry is sensitive to changes in oxygen saturation in pigs and correlated with intravitreal pO2-measurements and with femoral artery pO2. Pigs present a higher intra...

  17. Review: Interventional radiology in peripheral vascular disease

    International Nuclear Information System (INIS)

    Peripheral vascular diseases (PVD) are referred to as diseases affecting the blood vessels other than the heart and the brain. Interventional endovascular treatment whenever feasible has become the first line of management in the treatment of PVD. Interventions may be aimed at either revascularization or deliberate occlusion of a diseased vessel(s). This article reviews the various peripheral vascular diseases with their appropriate endovascular management

  18. Review: Interventional radiology in peripheral vascular disease

    OpenAIRE

    Cherian, Mathew P; Mehta, Pankaj; Tejas M Kalyanpur; Gupta, Prashanth

    2008-01-01

    Peripheral vascular diseases (PVD) are referred to as diseases affecting the blood vessels other than the heart and the brain. Interventional endovascular treatment whenever feasible has become the first line of management in the treatment of PVD. Interventions may be aimed at either revascularization or deliberate occlusion of a diseased vessel(s). This article reviews the various peripheral vascular diseases with their appropriate endovascular management.

  19. Retinal detachment following cataract surgery with capsulorhexis.

    OpenAIRE

    Kelley, J S; Doxanas, M T

    1995-01-01

    PURPOSE: To estimate the incidence of retinal detachment after cataract surgery with capsulorhexis. METHODS: A consecutive series of 2,150 cataract operations were followed for incidence of retinal detachment. A series of 1,000 patients from this group were analyzed for high risk factors: myopia, age, sex, operative complications and capsulotomy. RESULTS: With minimum one year follow up in 90% of patients the incidence of retinal detachment was 0.25% (5 cases). CONCLUSION: The true incidence ...

  20. Chronic granulomatous disease presenting as retinal mass

    OpenAIRE

    Ahmad M. Mansour; Al Dairy, Mays; Hamam, Rola; Hidayat, Ahmed A

    2008-01-01

    1-year-old girl was admitted for fever of unknown origin. Funduscopy revealed juxtapapillary retinal inflammatory mass in one eye with a differential diagnosis of sarcoidosis, tuberculosis, retinoblastoma or metastatic disease. Retinal biopsy showed necrotizing granulomatous retinitis. Extensive workup and therapeutic trials failed to confirm the diagnosis of tuberculosis or sarcoidosis. Her 7-month brother and 4-year-old male cousin presented with nystagmus, poor vision, paravascular pigment...

  1. Cytomegalovirus retinitis mimicking intraocular lymphoma

    OpenAIRE

    Gooi, Patrick

    2008-01-01

    Patrick Gooi1, James Farmer2, Bernard Hurley3, Elliott Brodbaker41Department of Ophthalmology, University of Calgary, Calgary, Alberta, Canada; 2Department of Pathology and Lab Medicine University of Ottawa and The Ottawa Hospital, Ottawa, Ontario, Canada; 3Department of Ophthalmology, University of Ottawa Eye Institute and The Ottawa Hospital, Ottawa, Ontario, Canada; 4Faculty of Medicine, University of Ottawa, Ottawa, Ontario, CanadaAbstract: We present a case of an unusual retinal infiltra...

  2. Astigmatism following retinal detachment surgery.

    OpenAIRE

    Goel, R.; Crewdson, J; Chignell, A H

    1983-01-01

    Eighty-three patients on whom successful retinal detachment had been performed were studied to note astigmatic changes following surgery. In the majority of cases the errors following such surgery are of no great clinical importance. However, in some situations a high degree of astigmatism may be produced. This study showed that these sequelae are particularly likely after radial buckling procedures, and surgeons favouring these techniques should be aware that astigmatic errors can be induced...

  3. 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.

  4. 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.

  5. Retinal Macroglial Responses in Health and Disease

    Science.gov (United States)

    de Hoz, Rosa; Rojas, Blanca; Ramírez, Ana I.; Salazar, Juan J.; Gallego, Beatriz I.; Triviño, Alberto; Ramírez, José M.

    2016-01-01

    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.

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

    Science.gov (United States)

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

    2015-02-01

    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. PMID:25324231

  7. Clinical features and etiology of retinal vasculitis in Northern Thailand

    Directory of Open Access Journals (Sweden)

    Supanut Apinyawasisuk

    2013-01-01

    Full Text Available Purpose: To report on the clinical features and etiology of patients with retinal vasculitis (RV. Materials and Methods: We reviewed medical records of 47 patients (75 affected eyes diagnosed with RV. Clinical presentations, ocular complications, associated systemic diseases, and treatment regimens were registered. Results: Etiology of RV included infectious causes in 10/47, (21% while an association with systemic and/or ocular non-infectious disorders was noted in 22/47 (47%. Eales′ disease and Behcet′s disease represented the most common clinical entities in non-infectious group while tuberculosis-associated RV was diagnosed in 6/10 (60% among those with infectious disorders. RV was bilateral in 28/47 (60% patients. Retinal veins were most commonly affected (72%, 34/47. Involvement of arteries was present in 12/47 (25% and was associated with viral infections and Behcet′s disease. Ocular complications developed in 60/75 (80% eyes. The most common complications were elevated intraocular pressure and/or glaucoma (33/75, 44%. Retinal detachment, vitreous hemorrhage, and cystoid macular edema developed in similar percentages (15%. Conclusions: RV in Thailand manifested mostly in male patients, was typically bilateral and involved mostly veins. Involvement of arteries was observed in patients with viral infections and Behcet′s disease. Tuberculosis was the most common infectious cause.

  8. Complications of emulsified silicone oil after retinal detachment repair.

    Science.gov (United States)

    Miller, John B; Papakostas, Thanos D; Vavvas, Demetrios G

    2014-01-01

    Intraocular silicone oil has several important indications in vitreoretinal surgery, particularly the repair of complicated retinal detachments. Emulsification is a clinically significant complication of using silicone oil tamponade. There are several factors that can promote or prevent silicone oil emulsification after retinal detachment repair, including protein surfactants, contaminants, and shear forces. However, the duration of tamponade remains the most significant one. After emulsification has occurred, keratopathy and glaucoma are the most common complications. However, recent work has shown that emulsification can also affect the retina, optic nerve, and even extraocular structures. Limiting the amount of time the silicone oil remains in the eye is the most important factor in reducing its complications. PMID:25325856

  9. Retinal Endothelial Cell Apoptosis Stimulates Recruitment of Endothelial Progenitor Cells

    Science.gov (United States)

    Bhatwadekar, Ashay D.; Glenn, Josephine V.; Curtis, Tim M.; Grant, Maria B.; Stitt, Alan W.; Gardiner, Tom A.

    2013-01-01

    Purpose Bone marrow–derived endothelial progenitor cells (EPCs) contribute to vascular repair although it is uncertain how local endothelial cell apoptosis influences their reparative function. This study was conducted to determine how the presence of apoptotic bodies at sites of endothelial damage may influence participation of EPCs in retinal microvascular repair. Methods Microlesions of apoptotic cell death were created in monolayers of retinal microvascular endothelial cells (RMECs) by using the photodynamic drug verteporfin. The adhesion of early-EPCs to these lesions was studied before detachment of the apoptotic cells or after their removal from the wound site. Apoptotic bodies were fed to normal RMECs and mRNA levels for adhesion molecules were analyzed. Results Endothelial lesions where apoptotic bodies were left attached at the wound site showed a fivefold enhancement in EPC recruitment (P < 0.05) compared with lesions where the apoptotic cells had been removed. In intact RMEC monolayers exposed to apoptotic bodies, expression of ICAM, VCAM, and E-selectin was upregulated by 5- to 15-fold (P < 0.05– 0.001). EPCs showed a characteristic chemotactic response (P < 0.05) to conditioned medium obtained from apoptotic bodies, whereas analysis of the medium showed significantly increased levels of VEGF, IL-8, IL-6, and TNF-α when compared to control medium; SDF-1 remained unchanged. Conclusions The data indicate that apoptotic bodies derived from retinal capillary endothelium mediate release of proangiogenic cytokines and chemokines and induce adhesion molecule expression in a manner that facilitates EPC recruitment. PMID:19474402

  10. Visual cortex controls retinal output in the rat.

    Science.gov (United States)

    Molotchnikoff, S; Tremblay, F

    1986-07-01

    The first objective of the present investigation was to shed more light on corticofugal influences on the retina by providing an analysis of the type and proportion of retinal ganglion cells that are affected by cooling the visual cortex in rats. The second question was to determine if the pretectum participates in functional cortico-retinal relationships. In urethane-anesthetized and paralyzed hooded rats, axonal activity of retinal ganglion cells was recorded with glass micropipettes at optic chiasm level. Units were classified as ON, OFF, suppressed-by-light and concentric. The visual cortex was inactivated by cooling its surface with a 4 mm2 steel probe using the Peltier effect. The pretectum was blocked with microinjections of 50 to 100 nanoliters of cobalt ions, lidocaine hydrochloride or KCl. The inactivations and recoveries at both sites were monitored by simultaneously recording evoked field potentials. Interrupting corticofugal impulses caused modifications of the evoked discharge pattern in all types of cells. The concentric type was the group least affected by cortical cooling. A common trend emerged suggesting that cooling of the visual cortex led to an enhancement of the initial evoked excitation. This was often followed by an enhanced post-excitatory inhibition. The Pearson coefficient allowed us to measure the degree of similarity between two histograms. When all data were pooled, a weak correlation between control and test histograms (r = 0.29, N = 56) was found, while the control and recovery patterns averaged a correlation of more than twice that size (r = 0.68). In a second series of experiments, the pretectum and visual cortex (VC) were simultaneously inactivated. It is shown that both sites summed their influence and acted synergistically upon the pattern of ganglion cell responses. The results strongly suggest that the visual cortex exerts a major control over the response pattern of thirty percent of retinal ganglion cells, and that the

  11. Effect of bevacizumab (Avastin™) on mitochondrial function of in vitro retinal pigment epithelial, neurosensory retinal and microvascular endothelial cells

    Science.gov (United States)

    Luthra, Saurabh; Sharma, Ashish; Dong, Joyce; Neekhra, Aneesh; Gramajo, Ana L; Seigel, Gail M; Kenney, M Cristina; Kuppermann, Baruch D

    2013-01-01

    Purpose: To evaluate the effect of bevacizumab on the mitochondrial function of human retinal pigment epithelial (ARPE-19), rat neurosensory retinal (R28) and human microvascular endothelial (HMVEC) cells in culture. Materials and Methods: ARPE-19 and R28 cells were treated with 0.125, 0.25, 0.50 and 1 mg/ml of bevacizumab. The HMVEC cultures were treated with 0.125, 0.25, 0.50 and 1 mg/ml of bevacizumab or 1 mg/ml of immunoglobulin G (control). Mitochondrial function assessed by mitochondrial dehydrogenase activity (MDA) was determined using the WST-1 assay. Results: Bevacizumab doses of 0.125 to 1 mg/ml for 5 days did not significantly affect the MDA of ARPE-19 cells. Bevacizumab treatment at 0.125 and 0.25 mg/ml (clinical dose) did not significantly affect the MDA of R28 cells; however, 0.50 and 1 mg/ml doses significantly reduced the R28 cell mitochondrial function. All doses of bevacizumab significantly reduced the MDA of proliferating and non-proliferating HMVEC. Conclusion: Bevacizumab exposure for 5 days was safe at clinical doses in both ARPE-19 and R28 retinal neurosensory cells in culture. By contrast, bevacizumab exposure at all doses show a significant dose-dependent decrease in mitochondrial activity in both the proliferating and non-proliferating HMVEC in vitro. This suggests a selective action of bevacizumab on endothelial cells at clinical doses. PMID:24413824

  12. Loss of Bmi1 causes anomalies in retinal development and degeneration of cone photoreceptors.

    Science.gov (United States)

    Barabino, Andrea; Plamondon, Vicky; Abdouh, Mohamed; Chatoo, Wassim; Flamier, Anthony; Hanna, Roy; Zhou, Shufeng; Motoyama, Noboru; Hébert, Marc; Lavoie, Joëlle; Bernier, Gilbert

    2016-05-01

    Retinal development occurs through the sequential but overlapping generation of six types of neuronal cells and one glial cell type. Of these, rod and cone photoreceptors represent the functional unit of light detection and phototransduction and are frequently affected in retinal degenerative diseases. During mouse development, the Polycomb group protein Bmi1 is expressed in immature retinal progenitors and differentiated retinal neurons, including cones. We show here that Bmi1 is required to prevent post natal degeneration of cone photoreceptors and bipolar neurons and that inactivation of Chk2 or p53 could improve but not overcome cone degeneration in Bmi1(-/-) mice. The retinal phenotype of Bmi1(-/-) mice was also characterized by loss of heterochromatin, activation of tandem repeats, oxidative stress and Rip3-associated necroptosis. In the human retina, BMI1 was preferentially expressed in cones at heterochromatic foci. BMI1 inactivation in human embryonic stem cells was compatible with retinal induction but impaired cone terminal differentiation. Despite this developmental arrest, BMI1-deficient cones recapitulated several anomalies observed in Bmi1(-/-) photoreceptors, such as loss of heterochromatin, activation of tandem repeats and induction of p53, revealing partly conserved biological functions between mouse and man. PMID:26965367

  13. Changes in ganglion cell physiology during retinal degeneration influence excitability by prosthetic electrodes

    Science.gov (United States)

    Cho, Alice; Ratliff, Charles; Sampath, Alapakkam; Weiland, James

    2016-04-01

    Objective. Here we investigate ganglion cell physiology in healthy and degenerating retina to test its influence on threshold to electrical stimulation. Approach. Age-related Macular Degeneration and Retinitis Pigmentosa cause blindness via outer retinal degeneration. Inner retinal pathways that transmit visual information to the central brain remain intact, so direct electrical stimulation from prosthetic devices offers the possibility for visual restoration. Since inner retinal physiology changes during degeneration, we characterize physiological properties and responses to electrical stimulation in retinal ganglion cells (RGCs) of both wild type mice and the rd10 mouse model of retinal degeneration. Main results. Our aggregate results support previous observations that elevated thresholds characterize diseased retinas. However, a physiology-driven classification scheme reveals distinct sub-populations of ganglion cells with thresholds either normal or strongly elevated compared to wild-type. When these populations are combined, only a weakly elevated threshold with large variance is observed. The cells with normal threshold are more depolarized at rest and exhibit periodic oscillations. Significance. During degeneration, physiological changes in RGCs affect the threshold stimulation currents required to evoke action potentials.

  14. 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.

  15. 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.

  16. Parental history of hypertension is associated with narrower retinal arteriolar caliber in young girls.

    Science.gov (United States)

    Gopinath, Bamini; Baur, Louise A; Hardy, Louise L; Wang, Jie Jin; Teber, Erdahl; Wong, Tien Y; Mitchell, Paul

    2011-09-01

    We aimed to assess the associations between parental history of hypertension and indicators of cardiovascular risk (retinal vessel diameter, presence of obesity, and elevated blood pressure) in prepubertal children. There were 1739 (77.7% of those eligible) 6-year-old students (863 girls and 876 boys) who were examined from a random cluster sample of 34 Sydney schools. Parents completed questionnaires about their medical conditions, including whether they have/had hypertension. Retinal images were taken with a digital fundus camera, and retinal vessel caliber was quantified using computer software. Anthropometric (height, weight, percentage of body fat, and body mass index) and blood pressure measures were collected. There were 160 children (9.2%) with a positive parental history of hypertension (either biological mother and/or father). Children with a positive versus negative parental history of hypertension had significantly higher body mass index (16.8 versus 16.5 kg/m(2); P=0.04) and systolic blood pressure (101.3 versus 99.8 mm Hg; P=0.01). Girls with positive versus negative parental history of hypertension had significantly higher diastolic blood pressure (≈3.1 mm Hg; P=0.01) and narrower retinal arteriolar caliber (≈4.3 μm; P=0.0004). Positive parental history of hypertension was not associated with mean retinal vascular caliber among boys. We show that a positive parental history of hypertension in healthy prepubertal girls, but not boys, is associated with narrower retinal arteriolar vessels, likely conveying a predisposition to develop hypertension later in life. These findings may indicate the need for cardiovascular disease prevention measures starting early in life among offspring of hypertensive parents. PMID:21768527

  17. Imaging Pediatric Vascular Lesions

    Science.gov (United States)

    Nguyen, Tuyet A.; Krakowski, Andrew C.; Naheedy, John H.; Kruk, Peter G.

    2015-01-01

    Vascular anomalies are commonly encountered in pediatric and dermatology practices. Most of these lesions are benign and easy to diagnose based on history and clinical exam alone. However, in some cases the diagnosis may not be clear. This may be of particular concern given that vascular anomalies may occasionally be associated with an underlying syndrome, congenital disease, or serious, life-threatening condition. Defining the type of vascular lesion early and correctly is particularly important to determine the optimal approach to management and treatment of each patient. The care of pediatric patients often requires collaboration from a multitude of specialties including pediatrics, dermatology, plastic surgery, radiology, ophthalmology, and neurology. Although early characterization of vascular lesions is important, consensus guidelines regarding the evaluation and imaging of vascular anomalies does not exist to date. Here, the authors provide an overview of pediatric vascular lesions, current classification systems for characterizing these lesions, the various imaging modalities available, and recommendations for appropriate imaging evaluation. PMID:26705446

  18. Imaging Pediatric Vascular Lesions.

    Science.gov (United States)

    Nguyen, Tuyet A; Krakowski, Andrew C; Naheedy, John H; Kruk, Peter G; Friedlander, Sheila Fallon

    2015-12-01

    Vascular anomalies are commonly encountered in pediatric and dermatology practices. Most of these lesions are benign and easy to diagnose based on history and clinical exam alone. However, in some cases the diagnosis may not be clear. This may be of particular concern given that vascular anomalies may occasionally be associated with an underlying syndrome, congenital disease, or serious, life-threatening condition. Defining the type of vascular lesion early and correctly is particularly important to determine the optimal approach to management and treatment of each patient. The care of pediatric patients often requires collaboration from a multitude of specialties including pediatrics, dermatology, plastic surgery, radiology, ophthalmology, and neurology. Although early characterization of vascular lesions is important, consensus guidelines regarding the evaluation and imaging of vascular anomalies does not exist to date. Here, the authors provide an overview of pediatric vascular lesions, current classification systems for characterizing these lesions, the various imaging modalities available, and recommendations for appropriate imaging evaluation. PMID:26705446

  19. 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

  20. TNFSF15 Inhibits Blood Retinal Barrier Breakdown Induced by Diabetes.

    Science.gov (United States)

    Jiang, Feng; Chen, Qingzhong; Huang, Liming; Wang, Ying; Zhang, Zhuhong; Meng, Xiangda; Liu, Yuanyuan; Mao, Chunjie; Zheng, Fang; Zhang, Jingkai; Yan, Hua

    2016-01-01

    Tumor necrosis factor superfamily 15 (TNFSF15) is an endogenous neovascularization inhibitor and an important negative regulator of vascular homeostasis. This study aimed to explore the potential role of TNFSF15 in diabetic retinopathy. Vitreous TNFSF15 and VEGF levels in proliferative diabetic retinopathy (PDR) patients were detected by ELISA. Retinal expression of TNFSF15 and the content of tight junction proteins (TJPs) in rats were detected by immunohistochemistry and Western blot, respectively. The blood retinal barrier (BRB) permeability was evaluated using Evans Blue (EB) dye. The TNFSF15/VEGF ratio was decreased in the vitreous fluid of patients with PDR relative to the controls, even though the expression levels of TNFSF15 were higher. TNFSF15 was dramatically decreased one month later after diabetes induction (p treatment significantly protected the BRB in the diabetic animals. Diabetes decreased TJPs levels in the retina, and these changes were inhibited by TNFSF15 treatment. Moreover, TNFSF15 decreased activation of VEGF both in mRNA and protein levels caused by diabetes. These results indicate that TNFSF15 is an important inhibitor in the progression of DR and suggest that the regulation of TNFSF15 shows promise for the development of diabetic retinopathy treatment strategies. PMID:27120595

  1. A dominant mutation in MAPKAPK3, an actor of p38 signaling pathway, causes a new retinal dystrophy involving Bruch's membrane and retinal pigment epithelium.

    Science.gov (United States)

    Meunier, Isabelle; Lenaers, Guy; Bocquet, Béatrice; Baudoin, Corinne; Piro-Megy, Camille; Cubizolle, Aurélie; Quilès, Mélanie; Jean-Charles, Albert; Cohen, Salomon Yves; Merle, Harold; Gaudric, Alain; Labesse, Gilles; Manes, Gaël; Péquignot, Marie; Cazevieille, Chantal; Dhaenens, Claire-Marie; Fichard, Agnès; Ronkina, Natalia; Arthur, Simon J; Gaestel, Matthias; Hamel, Christian P

    2016-03-01

    Inherited retinal dystrophies are clinically and genetically heterogeneous with significant number of cases remaining genetically unresolved. We studied a large family from the West Indies islands with a peculiar retinal disease, the Martinique crinkled retinal pigment epitheliopathy that begins around the age of 30 with retinal pigment epithelium (RPE) and Bruch's membrane changes resembling a dry desert land and ends with a retinitis pigmentosa. Whole-exome sequencing identified a heterozygous c.518T>C (p.Leu173Pro) mutation in MAPKAPK3 that segregates with the disease in 14 affected and 28 unaffected siblings from three generations. This unknown variant is predicted to be damaging by bioinformatic predictive tools and the mutated protein to be non-functional by crystal structure analysis. MAPKAPK3 is a serine/threonine protein kinase of the p38 signaling pathway that is activated by a variety of stress stimuli and is implicated in cellular responses and gene regulation. In contrast to other tissues, MAPKAPK3 is highly expressed in the RPE, suggesting a crucial role for retinal physiology. Expression of the mutated allele in HEK cells revealed a mislocalization of the protein in the cytoplasm, leading to cytoskeleton alteration and cytodieresis inhibition. In Mapkapk3-/- mice, Bruch's membrane is irregular with both abnormal thickened and thinned portions. In conclusion, we identified the first pathogenic mutation in MAPKAPK3 associated with a retinal disease. These findings shed new lights on Bruch's membrane/RPE pathophysiology and will open studies of this signaling pathway in diseases with RPE and Bruch's membrane alterations, such as age-related macular degeneration. PMID:26744326

  2. Vascularity in thyroid neoplasms

    DEFF Research Database (Denmark)

    Larsen, Karen Kjaer; Andersen, Niels Frost; Melsen, Flemming;

    2006-01-01

    The aim of the present study was to evaluate the reliability of four different methods (vascular grading, Chalkley count, microvessel density (MVD) and stereological estimation) for quantifying intratumoral microvascularity in thyroid neoplasms, by comparing the variability within and between...... count should be the preferred method for assessing microvascularity in thyroid neoplasms. The diagnostic evaluation revealed a tendency towards higher degree of vascularity in FA compared to both FC and PC for all methods. No statistically significant association was seen between vascular density and...

  3. 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. PMID:25127660

  4. Probabilistic graphical modeling of speckle statistics in laser speckle contrast imaging for noninvasive and label-free retinal angiography.

    Science.gov (United States)

    Basak, Kausik; Dey, Goutam; Sheet, Debdoot; Mahadevappa, Manjunatha; Mandal, Mahitosh; Dutta, Pranab K

    2015-08-01

    This paper introduces a noninvasive and label-free approach for retinal angiography using Laser speckle contrast imaging (LSCI). Retinal vessel structure is segmented using a Hidden Markov Random Field (HMRF) based model. Prior to that, k-means clustering is used to obtain initial parameter set and labels for HMRF. Final parameter set for HMRF is estimated using expectation-maximization (EM) algorithm and final labeling is achieved using maximum aposteriori (MAP) algorithm. Clique energy for HMRF is computed from eigenvalue analysis of structure tensor for each pixel. This helps to get connectivity in the direction of strongest tangents in its neighborhood, facilitating the tracking of fine vessels in retinal vascular network. Quantitative evaluation shows an average vessel segmentation accuracy of 96.41% in normal condition with substantial improvement in tracking capability of fine vessels. Changes in blood flow can be tracked and observed at segmented output; particularly applicable for the study of different pathological conditions. PMID:26737719

  5. Role of calcium-activated potassium channels with small conductance in bradykinin-induced vasodilation of porcine retinal arterioles

    DEFF Research Database (Denmark)

    Dalsgaard, Thomas; Kroigaard, Christel; Bek, Toke;

    2009-01-01

    PURPOSE: Endothelial dysfunction and impaired vasodilation may be involved in the pathogenesis of retinal vascular diseases. In the present study, the mechanisms underlying bradykinin vasodilation were examined and whether calcium-activated potassium channels of small (SK(Ca)) and intermediate (IK......(Ca)) conductance are involved in regulation of endothelium-dependent vasodilation in retinal arterioles was investigated. METHODS: Porcine retinal arterioles (diameter approximately 112 microm, N = 119) were mounted in microvascular myographs for isometric tension recordings. The arterioles were contracted with...... the thromboxane analogue, U46619, and concentration-response curves were constructed for bradykinin and a novel opener of SK(Ca) and IK(Ca) channels, NS309. RESULTS: In U46619-contracted arterioles, bradykinin and NS309 induced concentration-dependent relaxations. In vessels without endothelium...

  6. 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.

  7. 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.

  8. 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.

  9. Fundus autofluorescence applications in retinal imaging

    OpenAIRE

    Andrea Gabai; Daniele Veritti; Paolo Lanzetta

    2015-01-01

    Fundus autofluorescence (FAF) is a relatively new imaging technique that can be used to study retinal diseases. It provides information on retinal metabolism and health. Several different pathologies can be detected. Peculiar AF alterations can help the clinician to monitor disease progression and to better understand its pathogenesis. In the present article, we review FAF principles and clinical applications.

  10. Fundus autofluorescence applications in retinal imaging

    Directory of Open Access Journals (Sweden)

    Andrea Gabai

    2015-01-01

    Full Text Available Fundus autofluorescence (FAF is a relatively new imaging technique that can be used to study retinal diseases. It provides information on retinal metabolism and health. Several different pathologies can be detected. Peculiar AF alterations can help the clinician to monitor disease progression and to better understand its pathogenesis. In the present article, we review FAF principles and clinical applications.

  11. Fundus autofluorescence applications in retinal imaging.

    Science.gov (United States)

    Gabai, Andrea; Veritti, Daniele; Lanzetta, Paolo

    2015-05-01

    Fundus autofluorescence (FAF) is a relatively new imaging technique that can be used to study retinal diseases. It provides information on retinal metabolism and health. Several different pathologies can be detected. Peculiar AF alterations can help the clinician to monitor disease progression and to better understand its pathogenesis. In the present article, we review FAF principles and clinical applications. PMID:26139802

  12. 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. PMID:26855177

  13. Retinal vein occlusion: pathophysiology and treatment options

    OpenAIRE

    Karia, Niral

    2010-01-01

    Niral KariaDepartment of Ophthalmology, Southend Hospital, Prittlewell Chase, Westcliff on Sea, Essex, United KingdomAbstract: This paper reviews the current thinking about retinal vein occlusion. It gives an overview of its pathophysiology and discusses the evidence behind the various established and emerging treatment paradigms.Keywords: central, hemispheric, branch, retinal vein occlusion, visual loss

  14. Retinal vein occlusion: pathophysiology and treatment options

    Directory of Open Access Journals (Sweden)

    Niral Karia

    2010-07-01

    Full Text Available Niral KariaDepartment of Ophthalmology, Southend Hospital, Prittlewell Chase, Westcliff on Sea, Essex, United KingdomAbstract: This paper reviews the current thinking about retinal vein occlusion. It gives an overview of its pathophysiology and discusses the evidence behind the various established and emerging treatment paradigms.Keywords: central, hemispheric, branch, retinal vein occlusion, visual loss

  15. Prevalence of generalized retinal dystrophy in Denmark

    DEFF Research Database (Denmark)

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

    2014-01-01

    PURPOSE: Generalized retinal dystrophy is a frequent cause of visual impairment and blindness in younger individuals and a subject of new clinical intervention trials. Nonetheless, there are few nation-wide population-based epidemiological data of generalized retinal dystrophy. The purpose of thi...

  16. 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

  17. Role of aflibercept for macular edema following branch retinal vein occlusion: comparison of clinical trials

    Directory of Open Access Journals (Sweden)

    Oellers P

    2016-03-01

    Full Text Available Patrick Oellers,1,2 Dilraj S Grewal,1,2 Sharon Fekrat1,2 1Duke Eye Center, Duke University Medical Center, 2Surgical Service, Durham Veterans Affairs Medical Center, Durham, NC, USA Abstract: For years, the standard of care for branch-retinal-vein-occlusion-associated macular edema was initial observation followed by grid-pattern laser photocoagulation for persistent edema. Newer pharmacologic options have revolutionized the management of branch-retinal-vein-occlusion-associated macular edema, and the visual outcomes of these eyes are better than ever. However, a variety of available treatment options including intravitreal corticosteroids and intravitreal anti-vascular endothelial growth factor agents have established novel challenges with regard to appropriate drug selection. This review summarizes the available clinical studies with special emphasis on the comparison of intravitreal aflibercept with ranibizumab, bevacizumab, and steroid agents. Keywords: branch retinal vein occlusion, BRVO, macular edema, cystoid macular edema, grid-pattern laser photocoagulation, triamcinolone, dexamethasone implant, ranibizumab, bevacizumab, pegaptanib, anti-vascular endothelial growth factor

  18. Preparation and features of polycaprolactone vascular grafts with the incorporated vascular endothelial growth factor

    Science.gov (United States)

    Sevostyanova, V. V.; Khodyrevskaya, Y. I.; Glushkova, T. V.; Antonova, L. V.; Kudryavtseva, Y. A.; Barbarash, O. L.; Barbarash, L. S.

    2015-10-01

    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.

  19. 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.

  20. Preparation and features of polycaprolactone vascular grafts with the incorporated vascular endothelial growth factor

    International Nuclear Information System (INIS)

    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

  1. 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

  2. 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.

  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. PMID:25733527

  4. 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. PMID:27114552

  5. Retinal Artery Occlusion Treatment with Hyperbaric Oxygen

    Directory of Open Access Journals (Sweden)

    Harun Cakmak

    2016-01-01

    Full Text Available Retinal artery occlusion is one of the vision-threating emergency situations in ophthalmology. In this paper, a case of retinal artery occlusion is presented. Fifty seven year- old female patient presented with a sudden onset visual loss in her left eye. Best corrected visual acuity (BCVA levels were 1.0 and 0.7 in the right and left eye, respectiveley. Dilated fundus examination revealed no pathological finding in the right eye. Whereas calcified plaque was seen in upper arquat artery bifurcation in the left eye. Pallorness with retinal edema was seen in this arterial trace. Retinal artery occlusion was diagnosed and patient was referred for hyperbaric oxygen therapy. After a total of 20 sessions of hyperbaric oxygen therapy, the calcified plaques disappeared and her BCVA increased to 20/20. Hyperbaric oxygen treatment is vision-saving method which should be considered in retinal artery occlusion.

  6. Texton-based segmentation of retinal vessels

    Science.gov (United States)

    Adjeroh, Donald A.; Kandaswamy, Umasankar; Odom, J. Vernon

    2007-05-01

    With improvements in fundus imaging technology and the increasing use of digital images in screening and diagnosis, the issue of automated analysis of retinal images is gaining more serious attention. We consider the problem of retinal vessel segmentation, a key issue in automated analysis of digital fundus images. We propose a texture-based vessel segmentation algorithm based on the notion of textons. Using a weak statistical learning approach, we construct textons for retinal vasculature by designing filters that are specifically tuned to the structural and photometric properties of retinal vessels. We evaluate the performance of the proposed approach using a standard database of retinal images. On the DRIVE data set, the proposed method produced an average performance of 0.9568 specificity at 0.7346 sensitivity. This compares well with the best-published results on the data set 0.9773 specificity at 0.7194 sensitivity [Proc. SPIE5370, 648 (2004)].

  7. Lower limb vascular dysfunction in cyclists

    Directory of Open Access Journals (Sweden)

    Thiago Ayala Melo Di Alencar

    2013-06-01

    Full Text Available Sports-related vascular insufficiency affecting the lower limbs is uncommon, and early signs and symptoms can be confused with musculoskeletal injuries. This is also the case among professional cyclists, who are always at the threshold between endurance and excess training. The aim of this review was to analyze the occurrence of vascular disorders in the lower limbs of cyclists and to discuss possible etiologies. Eighty-five texts, including papers and books, published from 1950 to 2012, were used. According to the literature reviewed, some cyclists receive a late diagnosis of vascular dysfunction due to a lack of familiarity of the medical team with this type of dysfunction. Data revealed that a reduced blood flow in the external iliac artery, especially on the left, is much more common than in the femoral and popliteal arteries, and that vascular impairment is responsible for the occurrence of early fatigue and reduced performance in cycling.

  8. 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.

  9. Bone marrow-derived cells are differentially involved in pathological and physiological retinal angiogenesis in mice

    International Nuclear Information System (INIS)

    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 137Cs 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 bone

  10. Sildenafil alters retinal function in mouse carriers of retinitis pigmentosa.

    Science.gov (United States)

    Nivison-Smith, Lisa; Zhu, Yuan; Whatham, Andrew; Bui, Bang V; Fletcher, Erica L; Acosta, Monica L; Kalloniatis, Michael

    2014-11-01

    Sildenafil, the active ingredient in Viagra, has been reported to cause transient visual disturbance from inhibition of phosphodiesterase 6 (PDE6), a key enzyme in the visual phototransduction pathway. This study investigated the effects of sildenafil on the rd1(+/-) mouse, a model for carriers of Retinitis Pigmentosa which exhibit normal vision but may have a lower threshold for cellular stress caused by sildenafil due to a heterozygous mutation in PDE6. Sildenafil caused a dose-dependent decrease in electroretinogram (ERG) responses of normal mice which mostly recovered two days post administration. In contrast, rd1(+/-) mice exhibited a significantly reduced photoreceptor and a supernormal bipolar cell response to sildenafil within 1 h of treatment. Carrier mice retinae took two weeks to return to baseline levels suggesting sildenafil has direct effects on both the inner and outer retina and these effects differ significantly between normal and carrier mice. Anatomically, an increase in expression of the early apoptotic marker, cytochrome C in rd1(+/-) mice indicated that the effects of sildenafil on visual function may lead to degeneration. The results of this study are significant considering approximately 1 in 50 people are likely to be carriers of recessive traits leading to retinal degeneration. PMID:25239397

  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. Identification of two novel mutations in CDHR1 in consanguineous Spanish families with autosomal recessive retinal dystrophy

    OpenAIRE

    Konstantinos Nikopoulos; Almudena Avila-Fernandez; Marta Corton; Maria Isabel Lopez-Molina; Raquel Perez-Carro; Lara Bontadelli; Silvio Alessandro Di Gioia; Olga Zurita; Blanca Garcia-Sandoval; Carlo Rivolta; Carmen Ayuso

    2015-01-01

    Inherited retinal dystrophies present extensive phenotypic and genetic heterogeneity, posing a challenge for patients’ molecular and clinical diagnoses. In this study, we wanted to clinically characterize and investigate the molecular etiology of an atypical form of autosomal recessive retinal dystrophy in two consanguineous Spanish families. Affected members of the respective families exhibited an array of clinical features including reduced visual acuity, photophobia, defective color vision...

  13. 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

  14. Design and optimization of a retinal exposure detector

    Science.gov (United States)

    Van Derlofske, John F.; Bierman, Andrew; Rea, Mark S.; Maliyagoda, Nishantha

    2000-10-01

    The design and optimization of a retinal exposure detector for measuring the total amount of light entering the human eye and falling on the retina is presented. The retinal exposure device was designed by first determining the spatial efficiency function of the human eye system. This is accomplished by combining the spatial response function of the average human eye with a standard facial cutoff function. The eye's spatial efficiency function is ascertained through ray trace analysis with optical modeling software of published theoretical and biometric wide-angle eye models. All major factors affecting light propagation, such as volume attenuation, the gradient index of the lens, aspheric surface curvatures, partial reflection, and vignetting are included in the simulation. A practical metering device that mimics the calculated total eye system spatial response function was designed and optimized by again employing optical simulation software. The final design consisted of baffles, a lens system, a decentered aperture, an optical diffuser, optical filters, and a silicon photodiode. The response of the prototype retinal exposure detector device design was shown to match that of the theoretical eye response to within three percent.

  15. 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

  16. 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.

  17. Poikiloderma vasculare atrophicans

    OpenAIRE

    Padmavathy L; Prasad PVS; Prasanna K; Rao L

    1994-01-01

    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.

  18. Isolipidic diets differing in their essential fatty acid profiles affect the deposition of unsaturated neutral lipids in the intestine, liver and vascular system of Senegalese sole larvae and early juveniles

    OpenAIRE

    Boglino, A.; Gisbert, E.; Darias, Maria Jose; Estevez, A; Andree, K. B.; Sarasquete, C; Ortiz-Delgado, J.B.

    2012-01-01

    How lipid content and composition in the diet is utilized by the various organs and tissues of fish is reflected in their structure, such as the intestine through which dietary lipids are digested and absorbed, the vascular system which is involved in their transport, and the liver where lipids are stored and metabolized. However, no study has been conducted to compare the effect of different diets containing different levels of highly unsaturated fatty acids (HUFA) and essential fatty acids ...

  19. 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. PMID:25770055

  20. Vascular grading of angiogenesis

    DEFF Research Database (Denmark)

    Hansen, S; Grabau, D A; Sørensen, Flemming Brandt; Bak, M; Vach, W; Rose, C

    2000-01-01

    The study aimed to evaluate the prognostic value of angiogenesis by vascular grading of primary breast tumours, and to evaluate the prognostic impact of adding the vascular grade to the Nottingham Prognostic Index (NPI). The investigation included 836 patients. The median follow-up time was 11...... years and 4 months. The microvessels were immunohistochemically stained by antibodies against CD34. Angiogenesis was graded semiquantitatively by subjective scoring into three groups according to the expected number of microvessels in the most vascular tumour area. The vascular grading between observers...... had clinical impact for 24% of the patients, who had a shift in prognostic group, as compared to NPI, and implied a better prognostic dissemination. We concluded that the angiogenesis determined by vascular grading has independent prognostic value of clinical relevance for patients with breast cancer....

  1. [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. PMID:26597554

  2. Macrophages promote vasculogenesis of retinal neovascularization in an oxygen-induced retinopathy model in mice.

    Science.gov (United States)

    Gao, Xiang; Wang, Yu-Sheng; Li, Xiao-Qin; Hou, Hui-Yuan; Su, Jing-Bo; Yao, Li-Bo; Zhang, Jian

    2016-06-01

    To investigate the role of macrophages in oxygen-induced retinal neovascularization (NV) in mice, particularly the involvement of bone marrow-derived cells (BMCs) and the underlying mechanisms, BMCs from green fluorescent protein (GFP) transgenic mice were transplanted into postnatal day (P) 1 mice after irradiation. The mice were exposed to 75 % oxygen from P7 to P12 to initiate oxygen-induced retinopathy (OIR). The macrophages were depleted by injection of clodronate-liposomes (lip) intraperitoneally. The eyes were collected at P12 and P17. Retinal flatmounts and histopathological cross-sections were performed to analyze the severity of retinal NV and BMC recruitment. BMCs immunopositive for CD31 (PECAM-1; endothelial cell marker) and α-SMA (smooth muscle cell marker) antigens were detected using a confocal microscope. Expression of vascular endothelial growth factor (VEGF) and stromal cell-derived factor-1 (SDF-1) mRNA was detected by RT-PCR. The VEGF, SDF-1, CXCR4 and CD45 protein expression was detected by western blot examination. The retinal avascular area in OIR mice at P12 was unaffected after macrophage depletion carried out twice (38.27 ± 1.92 % reduction) using clodronate-lip. The retinal avascular area and the NV area at P17 were reduced after macrophage depletion four times (79.53 ± 1.02 % reduction); these findings were supported by retinal flatmounts and histopathological cross-sections. Macrophage depletion led to significant inhibition of BMC recruitment into the NV tufts at P17, with decreased expression of retinal VEGF, SDF-1, CXCR4 and CD45. The recruited BMCs differentiated primarily into CD31-positive endothelial cells (ECs) and α-SMA-positive smooth muscle cells (SMCs). This study suggested that macrophages promoted the vasculogenesis of retinal NV, particularly the contribution of BMCs in the mouse OIR model, which might be triggered by VEGF and SDF-1 production. PMID:26841878

  3. 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.

  4. 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.

  5. The effect of Delta-like ligand 4 monoclonal antibody on retinal neovascularization and vascular endothelial growth factor expression%Delta样配体4单克隆抗体对视网膜新生血管形成和血管内皮生长因子表达的影响

    Institute of Scientific and Technical Information of China (English)

    史少阳; 李迅; 裴存文; 陈晓隆

    2013-01-01

    .6±11.6)个/张,PBS对照组为(35.1±5.2)个/张,差异有统计学意义(t=-7.879,P=0.000). 结论 Dll4在视网膜新生血管形成的过程中发挥重要作用,并可能通过对VEGFR的反馈抑制发挥抑制病理性新生血管过度形成的作用.%Background Studieshowed thaDelta-like ligand 4 (Dll4) participatein the deveopmenof retinal celland angiogenesis.The Dll4-Notch pathway and vasculaendothelial growth facto(VEGF) are thoughto be critical mediatorof neovascularization undehypoxiconditions.The relationship between Dll4 and VEGF inovery cleaand furtheresearch ineeded.Objective Thistudy wato observe the inhibition of Dll4 on experimental retinal neovascularization and VEGF expression.MethodThe retinal neovascularization animal model wainduced by oxygen-induced retinopathy (OIR) in 5-day-old SPF SD ratby rearing the new postnatal ratwith the motherattogethein closed box with oxygen level a(80±2) % till 12-day-old.The ratwere then raised in normal aifo5 days.Aftethat,2.5μl (0.5 μg) of Dll4 monoclonal antibody wainjected into the mid-vitreoucavity in the righeye(Dll4 injected group) and PBwaused in the same way in the fellow eye(PBcontrol group) in the 12-day-old rats.Retinawere isolated in the 17-day-old rats,and retinal vasculamorphology waexamined by adenosine diphosphatease (ADPase) staining of retinal flatmounts,and the endotheliocyte nuclei above the internal limiting membrane were counted in the retinal tissue-slices.Reverse transcription PC(RT-PCR) waused to detecthe mRNexpression level of Dll4,VEGF,VEGF receptor-1 (VEGFR-1),VEGFR-2 and neuropilin-1 mRNin the retinas.Statistical analysiwaperformed by the paired t-test.The care and use of the animalcomplied with the Guidance Suggestion issued by the Ministry of Science and Technology of Chinin 2006.ResultThe Dll4 mRNexpression in the retin(Dll4 mRNA/β-actin mRNA) wa0.22± 0.06 and 0.98 ± 0.13 in the Dll4 injected group and the PBcontrol group,respectively,with statistically

  6. Vascular Complications of Cancer Chemotherapy.

    Science.gov (United States)

    Cameron, Alan C; Touyz, Rhian M; Lang, Ninian N

    2016-07-01

    Development of new anticancer drugs has resulted in improved mortality rates and 5-year survival rates in patients with cancer. However, many of the modern chemotherapies are associated with cardiovascular toxicities that increase cardiovascular risk in cancer patients, including hypertension, thrombosis, heart failure, cardiomyopathy, and arrhythmias. These limitations restrict treatment options and might negatively affect the management of cancer. The cardiotoxic effects of older chemotherapeutic drugs such as alkylating agents, antimetabolites, and anticancer antibiotics have been known for a while. The newer agents, such as the antiangiogenic drugs that inhibit vascular endothelial growth factor signalling are also associated with cardiovascular pathology, especially hypertension, thromboembolism, myocardial infarction, and proteinuria. Exact mechanisms by which vascular endothelial growth factor inhibitors cause these complications are unclear but impaired endothelial function, vascular and renal damage, oxidative stress, and thrombosis might be important. With increasing use of modern chemotherapies and prolonged survival of cancer patients, the incidence of cardiovascular disease in this patient population will continue to increase. Accordingly, careful assessment and management of cardiovascular risk factors in cancer patients by oncologists and cardiologists working together is essential for optimal care so that prolonged cancer survival is not at the expense of increased cardiovascular events. PMID:26968393

  7. Vascular oxidative stress: the common link in hypertensive and diabetic vascular disease

    OpenAIRE

    Cohen, Richard A.; Tong, XiaoYong

    2010-01-01

    Vascular disease in hypertension and diabetes is associated with increased oxidants. The oxidants arise from NADPH oxidase, xanthine oxidase, and mitochondria. Superoxide anion and hydrogen peroxide are produced by both leukocytes and vascular cells. Nitric oxide is produced in excess by inducible nitric oxide synthase, and the potent oxidant, peroxynitrite, is formed from superoxide and nitric oxide. The damage to proteins caused by oxidants is selective, affecting specific oxidant-sensitive...

  8. Neural remodeling in retinal degeneration.

    Science.gov (United States)

    Marc, Robert E; Jones, Bryan W; Watt, Carl B; Strettoi, Enrica

    2003-09-01

    Mammalian retinal degenerations initiated by gene defects in rods, cones or the retinal pigmented epithelium (RPE) often trigger loss of the sensory retina, effectively leaving the neural retina deafferented. The neural retina responds to this challenge by remodeling, first by subtle changes in neuronal structure and later by large-scale reorganization. Retinal degenerations in the mammalian retina generally progress through three phases. Phase 1 initiates with expression of a primary insult, followed by phase 2 photoreceptor death that ablates the sensory retina via initial photoreceptor stress, phenotype deconstruction, irreversible stress and cell death, including bystander effects or loss of trophic support. The loss of cones heralds phase 3: a protracted period of global remodeling of the remnant neural retina. Remodeling resembles the responses of many CNS assemblies to deafferentation or trauma, and includes neuronal cell death, neuronal and glial migration, elaboration of new neurites and synapses, rewiring of retinal circuits, glial hypertrophy and the evolution of a fibrotic glial seal that isolates the remnant neural retina from the surviving RPE and choroid. In early phase 2, stressed photoreceptors sprout anomalous neurites that often reach the inner plexiform and ganglion cell layers. As death of rods and cones progresses, bipolar and horizontal cells are deafferented and retract most of their dendrites. Horizontal cells develop anomalous axonal processes and dendritic stalks that enter the inner plexiform layer. Dendrite truncation in rod bipolar cells is accompanied by revision of their macromolecular phenotype, including the loss of functioning mGluR6 transduction. After ablation of the sensory retina, Müller cells increase intermediate filament synthesis, forming a dense fibrotic layer in the remnant subretinal space. This layer invests the remnant retina and seals it from access via the choroidal route. Evidence of bipolar cell death begins in

  9. Chickenpox Chorioretinitis with Retinal Exudates and Periphlebitis

    Directory of Open Access Journals (Sweden)

    Hirokuni Kitamei

    2012-05-01

    Full Text Available Background: Chickenpox is rarely associated with posterior segment inflammation. We report on a case of unilateral chickenpox chorioretinitis with retinal exudates and periphlebitis. Case Presentation: A 21-year-old healthy man, who suffered from chickenpox 2 weeks prior to symptom development, exhibited mild anterior chamber cells, vitreous opacity, sheathing of retinal veins, and yellow-white exudates in his right eye. Varicella zoster virus DNA was detected by polymerase chain reaction in the aqueous humor. He was treated with intravenous acyclovir followed by oral prednisolone and valaciclovir. Aqueous cells quickly disappeared and retinal exudates diminished within 1 month, leaving faint retinal scarring. Retinal arteritis had never been observed in this patient. Conclusions: Although the ocular findings in this case were similar to acute retinal necrosis (ARN, the clinical features differed from ARN in the following points: (1 mild anterior chamber inflammation, (2 absence of retinal arteritis, and (3 prompt resolution of inflammatory findings. The distinctive clinical features indicated that chorioretinitis associated with chickenpox may not have the same pathological conditions as ARN.

  10. 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

  11. 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.

  12. HIF-1alpha and HIF-2alpha are differentially activated in distinct cell populations in retinal ischaemia.

    Directory of Open Access Journals (Sweden)

    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

  13. Pediatric vascular access

    International Nuclear Information System (INIS)

    Pediatric interventional radiologists are ideally suited to provide vascular access services to children because of inherent safety advantages and higher success from using image-guided techniques. The performance of vascular access procedures has become routine at many adult interventional radiology practices, but this service is not as widely developed at pediatric institutions. Although interventional radiologists at some children's hospitals offer full-service vascular access, there is little or none at others. Developing and maintaining a pediatric vascular access service is a challenge. Interventionalists skilled in performing such procedures are limited at pediatric institutions, and institutional support from clerical staff, nursing staff, and technologists might not be sufficiently available to fulfill the needs of such a service. There must also be a strong commitment by all members of the team to support such a demanding service. There is a slippery slope of expected services that becomes steeper and steeper as the vascular access service grows. This review is intended primarily as general education for pediatric radiologists learning vascular access techniques. Additionally, the pediatric or adult interventional radiologist seeking to expand services might find helpful tips. The article also provides education for the diagnostic radiologist who routinely interprets radiographs containing vascular access devices. (orig.)

  14. Pediatric vascular access

    Energy Technology Data Exchange (ETDEWEB)

    Donaldson, James S. [Northwestern University, Feinberg School of Medicine, Department of Medical Imaging, Children' s Memorial Hospital, Chicago, IL (United States)

    2006-05-15

    Pediatric interventional radiologists are ideally suited to provide vascular access services to children because of inherent safety advantages and higher success from using image-guided techniques. The performance of vascular access procedures has become routine at many adult interventional radiology practices, but this service is not as widely developed at pediatric institutions. Although interventional radiologists at some children's hospitals offer full-service vascular access, there is little or none at others. Developing and maintaining a pediatric vascular access service is a challenge. Interventionalists skilled in performing such procedures are limited at pediatric institutions, and institutional support from clerical staff, nursing staff, and technologists might not be sufficiently available to fulfill the needs of such a service. There must also be a strong commitment by all members of the team to support such a demanding service. There is a slippery slope of expected services that becomes steeper and steeper as the vascular access service grows. This review is intended primarily as general education for pediatric radiologists learning vascular access techniques. Additionally, the pediatric or adult interventional radiologist seeking to expand services might find helpful tips. The article also provides education for the diagnostic radiologist who routinely interprets radiographs containing vascular access devices. (orig.)

  15. 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.

  16. Whole genome assessment of the retinal response to diabetes reveals a progressive neurovascular inflammatory response

    Directory of Open Access Journals (Sweden)

    Brucklacher Robert M

    2008-06-01

    Full Text Available Abstract Background Despite advances in the understanding of diabetic retinopathy, the nature and time course of molecular changes in the retina with diabetes are incompletely described. This study characterized the functional and molecular phenotype of the retina with increasing durations of diabetes. Results Using the streptozotocin-induced rat model of diabetes, levels of retinal permeability, caspase activity, and gene expression were examined after 1 and 3 months of diabetes. Gene expression changes were identified by whole genome microarray and confirmed by qPCR in the same set of animals as used in the microarray analyses and subsequently validated in independent sets of animals. Increased levels of vascular permeability and caspase-3 activity were observed at 3 months of diabetes, but not 1 month. Significantly more and larger magnitude gene expression changes were observed after 3 months than after 1 month of diabetes. Quantitative PCR validation of selected genes related to inflammation, microvasculature and neuronal function confirmed gene expression changes in multiple independent sets of animals. Conclusion These changes in permeability, apoptosis, and gene expression provide further evidence of progressive retinal malfunction with increasing duration of diabetes. The specific gene expression changes confirmed in multiple sets of animals indicate that pro-inflammatory, anti-vascular barrier, and neurodegenerative changes occur in tandem with functional increases in apoptosis and vascular permeability. These responses are shared with the clinically documented inflammatory response in diabetic retinopathy suggesting that this model may be used to test anti-inflammatory therapeutics.

  17. Choroidal mast cells in retinal pathology: a potential target for intervention.

    Science.gov (United States)

    Bousquet, Elodie; Zhao, Min; Thillaye-Goldenberg, Brigitte; Lorena, Viera; Castaneda, Beatriz; Naud, Marie Christine; Bergin, Ciara; Besson-Lescure, Bernadette; Behar-Cohen, Francine; de Kozak, Yvonne

    2015-08-01

    Mast cells are important in the initiation of ocular inflammation, but the consequences of mast cell degranulation on ocular pathology remain uncharacterized. We induced mast cell degranulation by local subconjunctival injection of compound 48/80. Initial degranulation of mast cells was observed in the choroid 15 minutes after the injection and increased up to 3 hours after injection. Clinical signs of anterior segment inflammation paralleled mast cell degranulation. With the use of optical coherence tomography, dilation of choroidal vessels and serous retinal detachments (SRDs) were observed and confirmed by histology. Subconjunctival injection of disodium cromoglycate significantly reduced the rate of SRDs, demonstrating the involvement of mast cell degranulation in posterior segment disorders. The infiltration of polymorphonuclear and macrophage cells was associated with increased ocular media concentrations of tumor necrosis factor-α, CXCL1, IL-6, IL-5, chemokine ligand 2, and IL-1β. Analysis of the amounts of vascular endothelial growth factor and IL-18 showed an opposite evolution of vascular endothelial growth factor compared with IL-18 concentrations, suggesting that they regulate each other's production. These findings suggest that the local degranulation of ocular mast cells provoked acute ocular inflammation, dilation, increased vascular permeability of choroidal vessels, and SRDs. The involvement of mast cells in retinal diseases should be further investigated. The pharmacologic inhibition of mast cell degranulation may be a potential target for intervention. PMID:26166807

  18. 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.

  19. Retinal isomerization dynamics in dry bacteriorhodopsin films

    Science.gov (United States)

    Colonna, Anne; Groma, Géza I.; Vos, Marten H.

    2005-10-01

    The primary photoprocesses in neutral and acid forms of oriented dried bacteriorhodopsin films were investigated by femtosecond absorption spectroscopy. The excitation energy dependence of the signals was used to distinguish photochemistry from processes involving photophysics of photocycle intermediates. Both the kinetics and the quantum yield of all- trans excited state decay by retinal photoisomerization and subsequent J → K transition were found to be very similar as in hydrated environments. Therefore, unlike slower photocycle phases, communication of the retinal with the environment does not play a role in retinal isomerization. Our results are important for understanding recent nonlinear optical applications of such films.

  20. Concurrent central retinal artery occlusion and branch retinal vein occlusion in giant cell arteritis

    OpenAIRE

    Chu, Edward

    2010-01-01

    Edward R Chu, Celia S ChenDepartment of Ophthalmology, Flinders Medical Centre and Flinders University, Bedford Park, SA, AustraliaAbstract: Ophthalmic involvement in giant cell arteritis can manifest in a number of ways. Central retinal artery occlusion is one of the common causes of visual loss in giant cell arteritis. On the contrary, branch retinal vein occlusion is rarely associated with the latter. We report an 89-year-old lady with acute left central retinal artery occlusion on a backg...

  1. 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.

  2. 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.

  3. Sequential occlusion of the branch retinal artery and branch retinal vein in a patient with hypertension: an interventional case report

    OpenAIRE

    Okamoto, Norio; Matsumoto, Chota; Shimomura, Yoshikazu

    2014-01-01

    Background There are some cases that reported central retinal vein occlusion accompanied by ciliary artery occlusion, however, combined branch retinal artery and vein occlusion is a rare condition that has been infrequently reported. We describe in this report one case of retinal vein occlusion and branch retinal artery occlusion occurring simultaneously. Case presentation A 50 year-old woman presented with acute visual loss in her right eye. Fundus photography showed retinal ischemia and tor...

  4. Retinal Remodeling in the Tg P347L Rabbit, a Large-Eye Model of Retinal Degeneration

    OpenAIRE

    Jones, Bryan William; Kondo, Mineo; Terasaki, Hiroko; Watt, Carl Brock; Rapp, Kevin; Anderson, James; Lin, Yanhua; Shaw, Marguerite Victoria; Yang, Jia-Hui; Marc, Robert Edward

    2011-01-01

    Retinitis pigmentosa (RP) is an inherited blinding disease characterized by progressive loss of retinal photo-receptors. There are numerous rodent models of retinal degeneration, but most are poor platforms for interventions that will translate into clinical practice. The rabbit possesses a number of desirable qualities for a model of retinal disease including a large eye and an existing and substantial knowledge base in retinal circuitry, anatomy, and ophthalmology. We have analyzed degenera...

  5. Glucocorticoids induce transactivation of tight junction genes occludin and claudin-5 in retinal endothelial cells via a novel cis-element.

    Science.gov (United States)

    Felinski, Edward A; Cox, Amy E; Phillips, Brett E; Antonetti, David A

    2008-06-01

    Tight junctions between vascular endothelial cells help to create the blood-brain and blood-retinal barriers. Breakdown of the retinal tight junction complex is problematic in several disease states including diabetic retinopathy. Glucocorticoids can restore and/or preserve the endothelial barrier to paracellular permeability, although the mechanism remains unclear. We show that glucocorticoid treatment of primary retinal endothelial cells increases content of the tight junction proteins occludin and claudin-5, co-incident with an increase in barrier properties of endothelial monolayers. The glucocorticoid receptor antagonist RU486 reverses both the glucocorticoid-stimulated increase in occludin content and the increase in barrier properties. Transcriptional activity from the human occludin and claudin-5 promoters increases in retinal endothelial cells upon glucocorticoid treatment, and is dependent on the glucocorticoid receptor (GR) as demonstrated by siRNA. Deletion analysis of the occludin promoter reveals a 205bp sequence responsible for the glucocorticoid response. However, this region does not possess a canonical glucocorticoid response element and does not bind to the GR in a chromatin immunoprecipitation (ChIP) assay. Mutational analysis of this region revealed a novel 40bp occludin enhancer element (OEE), containing two highly conserved regions of 10 and 13 base pairs, that is both necessary and sufficient for glucocorticoid-induced gene expression in retinal endothelial cells. These data suggest a novel mechanism for glucocorticoid induction of vascular endothelial barrier properties through increased occludin and claudin-5 gene expression. PMID:18501346

  6. The pleiotropic effects of simvastatin on retinal microvascular endothelium has important implications for ischaemic retinopathies.

    Directory of Open Access Journals (Sweden)

    Reinhold J Medina

    Full Text Available BACKGROUND: Current guidelines encourage the use of statins to reduce the risk of cardiovascular disease in diabetic patients; however the impact of these drugs on diabetic retinopathy is not well defined. Moreover, pleiotropic effects of statins on the highly specialised retinal microvascular endothelium remain largely unknown. The objective of this study was to investigate the effects of clinically relevant concentrations of simvastatin on retinal endothelium in vitro and in vivo. METHODS AND FINDINGS: Retinal microvascular endothelial cells (RMECs were treated with 0.01-10 microM simvastatin and a biphasic dose-related response was observed. Low concentrations enhanced microvascular repair with 0.1 microM simvastatin significantly increasing proliferation (p<0.05, and 0.01 microM simvastatin significantly promoting migration (p<0.05, sprouting (p<0.001, and tubulogenesis (p<0.001. High concentration of simvastatin (10 microM had the opposite effect, significantly inhibiting proliferation (p<0.01, migration (p<0.01, sprouting (p<0.001, and tubulogenesis (p<0.05. Furthermore, simvastatin concentrations higher than 1 microM induced cell death. The mouse model of oxygen-induced retinopathy was used to investigate the possible effects of simvastatin treatment on ischaemic retinopathy. Low dose simvastatin (0.2 mg/Kg promoted retinal microvascular repair in response to ischaemia by promoting intra-retinal re-vascularisation (p<0.01. By contrast, high dose simvastatin(20 mg/Kg significantly prevented re-vascularisation (p<0.01 and concomitantly increased pathological neovascularisation (p<0.01. We also demonstrated that the pro-vascular repair mechanism of simvastatin involves VEGF stimulation, Akt phosphorylation, and nitric oxide production; and the anti-vascular repair mechanism is driven by marked intracellular cholesterol depletion and related disorganisation of key intracellular structures. CONCLUSIONS: A beneficial effect of low

  7. 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.

  8. Comparative proteomic analysis of histone post-translational modifications upon ischemia/reperfusion-induced retinal injury

    DEFF Research Database (Denmark)

    Zhao, Xiaolu; Sidoli, Simone; Wang, Leilei; Wang, Wenjun; Guo, Lin; Jensen, Ole Nørregaard; Zheng, Ling

    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...... provides a sensitive and accurate way to dissect the changes in the histone code after retinal injury. Specifically, DNA damage associated histone PTMs may contribute to neurovascular degeneration during the process of ischemia/reperfusion injury....

  9. Optimizing the treatment of rhegmatogenous retinal detachment.

    Science.gov (United States)

    Hajari, Javad Nouri

    2016-03-01

    Surgical approaches for rhegmatogenous retinal detachment (RRD) have evolved rapidly in the past century. This has resulted in an increase in the anatomical success rate from zero per cent in the beginning of the 1900s to now almost 100 per cent. Rhegmatogenous retinal detachment is regarded as an acute eye disease that needs immediate treatment. With the increasing number of cataract surgeries and an increased elderly population, the numbers of RRD occurrences are increasing. The aim of this thesis is to create knowledge on how treatment and care of RRD patients can be optimized. In the first paper, data on the incidence of RRD in Denmark are presented based on data from a nation register the National Patient Registry (NPR). It was discovered that the incidence of RRD in Denmark is similar to previous reported numbers and that the incidence has been increasing due to increasing numbers of cataract surgeries and an increased elderly population. Using data from the NPR, we estimated that the risk of a RRD occurring on the fellow eye is 100 times larger than on the first eye and that middle aged men have the highest risk. Having an increase in the incidence of RRD we need to ensure that the patients are also treated in the most optimal way. To ensure this, an indicator is needed to monitor the quality at the different centres. This indicator presented in the second paper is based in the occurrence of redetachment. We define a detachment to be caused by poor surgery if the retina detaches within one year after initial surgery with pneumatic retinopexy, scleral buckling and VTX with gas, and one and a half years after surgery with VTX with oil. Also lack of oil removal within the first year is a failed operation. It is widely accepted that RRD is an acute disease but when should surgery be performed to attain the most optimal result? In the third paper, we evaluated the progression of posterior RRD with an optical coherence tomography to make an objective assessment of

  10. Congenital Vascular Malformation

    Science.gov (United States)

    ... clots, obstruction of major vessels, causing progressive limb asymmetry by overgrowth, and for cosmetic indications or because ... t he Vascular Disease Foundation (VDF) develops educational information and initiatives for patients, their families and friends, ...

  11. Vascular Access for Hemodialysis

    Science.gov (United States)

    ... for short-term use. [ Top ] What is an arteriovenous fistula? An AV fistula is a connection, made by ... to remove and return blood during hemodialysis. An arteriovenous (AV) fistula is a connection, made by a vascular surgeon, ...

  12. Heart and vascular services

    Science.gov (United States)

    ... Repair of aneurysms (dilated/enlarged portions) of the aorta and its branches Procedures may also be used ... Nutrition and lifestyle counseling, including smoking cessation and diabetes education Supervised exercise Alternative Names Circulatory system; Vascular ...

  13. Management of Vascular Malformations

    Directory of Open Access Journals (Sweden)

    Sadanori Akita, MD, PhD

    2014-03-01

    Conclusions: Treatment of vascular malformations is an integral part of multidisciplinary approaches. Venous malformations are more frequent in combination surgery, and if there are fewer complications, the patients’ satisfaction increases.

  14. 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.

  15. Acute Retinal Necrosis in Childhood

    Directory of Open Access Journals (Sweden)

    Yoav Y. Pikkel

    2014-05-01

    Full Text Available Background: Acute retinal necrosis (ARN is a viral syndrome consisting of uveitis/vitritis, occlusive vasculitis and peripheral necrosis. Few incidents are reported in children. The etiology is reactivated herpes simplex virus (HSV or varicella-zoster virus (VZV. Treatment with acyclovir is often used. The administration of oral glucocorticosteroids is of unproven benefit. Prognosis is variable but poor. Methods: Three weeks after contracting mild chickenpox, a healthy 4-year-old girl developed blurred vision in her right eye. Severely reduced visual acuity was noted, together with anterior uveitis, ‘mutton-fat' precipitates and vitral flare. Retinal vasculitis with necrosis was present. Serology for toxoplasma, cytomegalovirus and HIV was negative, while HSV and VZV IgG antibodies were positive. She was treated with 30 mg/kg of intravenous methylprednisolone (3 days, 30 mg of oral prednisone (3 days, and tapering for 8 weeks. Intravenous acyclovir was given for 10 days, followed by oral acyclovir for 4 months. Aspirin (100 mg/day was given for 4 months. Results: At 12 months, the girl felt good. Her right eye acuity was 6/9, with an intraocular pressure of 17 mm Hg. The peripheral retina showed scarring but no detachment. Conclusions: This is the first report of a once-daily high-dose methylprednisolone pulse therapy in one of the youngest known ARN cases. Pulsed steroid therapy was based on its known effectiveness in vasculitis, which is the main pathophysiology in ARN. There was no evidence of steroid-related viral over-replication. Our case achieved an excellent clinical and ophthalmic recovery in spite of the poor prognosis. The positive result of this case report provides a basis for further evaluation of high-dose steroid pulse therapy in ARN.

  16. Vascular Effects of Histamine.

    Science.gov (United States)

    Ebeigbe, Anthony B; Talabi, Olufunke O

    2014-01-01

    Four subtypes of receptors (H1, H2, H3 and H4) mediate the actions of histamine. In the vascular wall, the effects of histamine are mediated via H1 and H2 receptors and the actions are modulated by H3 receptor subtype located on presynaptic neurones. Alterations in vascular responses to histamine are associated with experimental as well as a human form of hypertension, suggesting a role for histanine in cardiovascular regulation. PMID:26196559

  17. Digital vascular imaging (DVI)

    International Nuclear Information System (INIS)

    Digitization of the video signals from an image intensifier/TV chain, followed by subtraction, contrast enchancement and reconversion to analogue signals, enables high quality angiographic images to be obtained from an intravenous injection of contrast medium. As the examination is basically noninvasive it can be used in outpatients. The possibilities of Digital Vascular Imaging are demonstrated by images obtained from the various vascular regions using a triple-mode 14 in. image intensifier with a Plumbicon. TV tube. (Auth.)

  18. Cost and Selection of Ophthalmic Anti-Vascular Endothelial Growth Factor Agents.

    Science.gov (United States)

    Li, Emily; Greenberg, Paul B; Voruganti, Indu; Krzystolik, Magdalena G

    2016-01-01

    Anti-vascular endothelial growth factor (anti-VEGF) drugs - ranibizumab, aflibercept, and off-label bevacizumab - are vital to the treatment of common retinal diseases, including exudative age-related macular degeneration (AMD), diabetic macular edema (DME), and macular edema (ME) associated with retinal vein occlusion (RVO). Given the high prevalence of AMD and retinal vascular diseases, anti-VEGF agents represent a large cost burden to the United States (US) healthcare system. Although ranibizumab and aflibercept are 30-fold more expensive per injection than bevacizumab, the two more costly medications are commonly used in the US, even though all three have been shown to be effective and safe for treatment of these retinal diseases. We investigated the availability and content of professional ophthalmic guidelines on cost consideration in the selection of anti-VEGF agents. We found that current professional guidelines were limited in availability and lacked specific guidance on cost-based anti-VEGF drug selection. This represents a missed opportunity to encourage the practice of value-based medicine. [Full article available at http://rimed.org/rimedicaljournal-2016-05.asp, free with no login]. PMID:27128510

  19. 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.

  20. 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.; Hannibal, Jens; Munarini, A; Mantovani, V; Bardoni, P; Cantalupo, G; Tozer, K.R.; Sancisi, E; Salomao, S.R.; Moraes, M.N.; Moraes-Filho, M.N.; Heegaard, Steffen; Milea, Dan; Kjer, Poul; Montagna, P; Carelli, V

    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...... 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...... subjects as in controls, indicating that the retinohypothalamic tract is sufficiently preserved to drive light information detected by melanopsin retinal ganglion cells. We then investigated the histology of post-mortem eyes from two patients with Leber hereditary optic neuropathy and one case with...

  1. [Zaidemberg's vascularized radial graft].

    Science.gov (United States)

    Saint-Cast, Y

    2010-12-01

    In 1991, Carlos Zaidemberg described a new technique to repair scaphoid non-unions with a vascularized bone graft harvested from the radial styloid process. An anatomic study based on 30 dissections after colorized latex injection established the constancy of the radial styloid process's artery, while showing that its origin, course and length were subject to variations. In a retrospective series of 38 cases over a period of 10 years, the vascularized bone graft was indicated for: (1) scaphoid non-union with the presence of avascular changes of the proximal fragment (23 cases); (2) failed prior reconstruction with bone graft and internal fixation (nine cases); (3) degenerative styloid-scaphoid arthritis (three cases); (4) fracture on Preiser dystrophy (three cases). The five steps of the simplified operative technique without dissection of the vascular pedicle include: (1) longitudinal dorso-radial approach, identification of the periosteal portion of the radial styloid process artery; (2) incision of the first and second compartments, longitudinal arthrotomy under the second compartment; (3) styloidectomy and transversal resection of the scaphoid non-union and sclerotic bone; (4) elevation of the vascularized bone graft; (5) transversal and radial insertion of the vascularized bone graft, osteosynthesis by two or three K-wire touching the scaphoid's radial edge. Scaphoid union was obtained in 33 cases out of 38. The only postoperative complications were two transient radial paresthesia. The standardized surgical procedure using vascularized bone graft harvested from the radial styloid process provides an efficient scaphoid reconstruction. PMID:21087882

  2. Novel Transgenic Mouse Models Develop Retinal Changes Associated with Early Diabetic Retinopathy Similar to Those Observed in Rats with Diabetes Mellitus

    Science.gov (United States)

    Guo, Changmei; Zhang, Zifeng; Zhang, Peng; Makita, Jun; Kawada, Hiroyoshi; Blessing, Karen; Kador, Peter F.

    2014-01-01

    Retinal capillary pericyte degeneration has been linked to aldose reductase (AR) activity in diabetic retinopathy (DR). Since the development of DR in mice and rats has been reported to differ and that this may be linked to differences in retinal sorbitol levels, we have established new murine models of early onset diabetes mellitus as tools for investigating the role of AR in DR. Transgenic diabetic mouse models were developed by crossbreeding diabetic C57BL/6-Ins2Akita/J (AK) with transgenic C57BL mice expressing green fluorescent protein (GFP), human aldose reductase (hAR) or both in vascular tissues containing smooth muscle actin-α (SMAA). Changes in retinal sorbitol levels were determined by HPLC while changes of growth factors and signaling were investigated by Western Blots. Retinal vascular changes were quantitatively analyzed on elastase-digestion flat mounts. Results show that sorbitol levels were higher in neural retinas of diabetic AK-SMAA-GFP-hAR compared to AK-SMAA-GFP mice. AK-SMAA-GFP-hAR mice showed induction of the retinal growth factors VEGF, IGF-1, bFGF and TGFβ, as well as signaling changes in P-Akt, P-SAPK/JNK, and P-44/42 MAPK. Increased loss of nuclei per capillary length and a significant increase in the percentage of acellular capillaries presented in 18 week old AK-SMAA-GFP-hAR mice. These changes are similar to those observed in streptozotocin-induced diabetic rats. Retinal changes in both mice and rats were prevented by inhibition of AR. These studies confirm that the increased expression of AR in mice results in the development of retinal changes associated with the early stages of DR that are similar to those observed in rats. PMID:24370601

  3. Complete Blood Count and Retinal Vessel Calibers

    OpenAIRE

    Liew, Gerald; Wang, Jie Jin; Rochtchina, Elena; Wong, Tien Yin; Mitchell, Paul

    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 at...

  4. Retinal Prosthetics, Optogenetics, and Chemical Photoswitches

    OpenAIRE

    Marc, Robert; Pfeiffer, Rebecca; Jones, Bryan

    2014-01-01

    Three technologies have emerged as therapies to restore light sensing to profoundly blind patients suffering from late-stage retinal degenerations: (1) retinal prosthetics, (2) optogenetics, and (3) chemical photoswitches. Prosthetics are the most mature and the only approach in clinical practice. Prosthetic implants require complex surgical intervention and provide only limited visual resolution but can potentially restore navigational ability to many blind patients. Optogenetics uses viral ...

  5. 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.

  6. Delayed appearance of high altitude retinal hemorrhages.

    Directory of Open Access Journals (Sweden)

    Daniel Barthelmes

    Full Text Available BACKGROUND: Retinal hemorrhages have been described as a component of high altitude retinopathy (HAR in association with altitude illness. In this prospective high altitude study, we aimed to gain new insights into the pathophysiology of HAR and explored whether HAR could be a valid early indicator of altitude illness. METHODOLOGY/PRINCIPAL FINDINGS: 28 mountaineers were randomly assigned to two ascent profiles during a research expedition to Mt. Muztagh Ata (7546 m/24,751 ft. Digital fundus photographs were taken prior to expedition at 490 m (1,607 ft, during expedition at 4497 m (14,750 ft = base camp, 5533 m (18,148 ft, 6265 m (20,549 ft, 6865 m (22,517 ft and 4.5 months thereafter at 490 m. Number, size and time of occurrence of hemorrhages were recorded. Oxygen saturation (SpO₂ and hematocrit were also assessed. 79% of all climbers exhibited retinal hemorrhages during the expedition. Number and area of retinal bleeding increased moderately to medium altitudes (6265 m. Most retinal hemorrhages were detected after return to base camp from a high altitude. No post-expeditional ophthalmic sequelae were detected. Significant negative (SpO₂ Beta: -0.4, p<0.001 and positive (hematocrit Beta: 0.2, p = 0.002, time at altitude Beta: 0.33, p = 0.003 correlations with hemorrhages were found. CONCLUSIONS/SIGNIFICANCE: When closely examined, a very large amount of climbers exhibit retinal hemorrhages during exposure to high altitudes. The incidence of retinal hemorrhages may be greater than previously appreciated as a definite time lag was observed between highest altitude reached and development of retinal bleeding. Retinal hemorrhages should not be considered warning signs of impending severe altitude illness due to their delayed appearance.

  7. Multimodal Imaging in Hereditary Retinal Diseases

    OpenAIRE

    Francesco Pichi; Mariachiara Morara; Chiara Veronese; Paolo Nucci; Ciardella, Antonio P.

    2013-01-01

    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...

  8. Effects of aging in retinal image quality.

    OpenAIRE

    Artal, Pablo; Ferro, Manuel; Miranda, Ismael; Navarro, Rafael

    1993-01-01

    The retinal image quality characterized by the modulation-transfer function of the eye was measured for two groups of subjects aged in the late twenties and mid sixties, respectively. In both groups, we obtained modulation transfer functions by using a double-pass method under the same experimental conditions: 4-mm artificial pupil, paralyzed accommodation, and objective control of the refractive state and centering. Results showed lower values of modulation in the retinal image for older ...

  9. Retinal Macroglial Responses in Health and Disease

    OpenAIRE

    de Hoz, Rosa; Rojas, Blanca; Ramírez, Ana I.; Salazar, Juan J; Gallego, Beatriz I.; Triviño, Alberto; Ramírez, José M.

    2016-01-01

    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 removin...

  10. 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.

  11. Retinal blood flow in diabetic retinopathy.

    OpenAIRE

    Patel, V.; Rassam, S; NEWSOM, R.; Wiek, J; Kohner, E.

    1992-01-01

    OBJECTIVES--(a) To report on the basic parameters of retinal blood flow in a population of diabetic patients with and without retinopathy and non-diabetic controls; (b) to formulate a haemodynamic model for the pathogenesis of diabetic retinopathy from this and other studies. DESIGN--Laser-Doppler velocimetry and computerised image analysis to determine retinal blood flow in a large cross sectional study. SETTING--Diabetic retinopathy outpatient clinic. SUBJECTS--24 non-diabetic controls and ...

  12. 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

  13. Vascular and Cardiac Target Organ Damage in Type 2 Diabetics With and Without Diabetic Retinopathy

    OpenAIRE

    Francisco Leon-Garrigosa; Jessica M Schrieber; J. Javier Servat; Luis Garcia-Ortiz; Jose Ignacio Recio-Rodriguez; Ma Carmen Patino-Alonso; Cristina Agudo-Conde; Emiliano Rodriguez Sanchez; Manuel Angel Gomez-Marcos

    2013-01-01

    Objective: In this study, we sought to assess the differences in cardiac and vascular end-organ damage in type 2 diabetics, with and without diabetic retinopathy. Methods: A cross-sectional study of 131 diabetic patients (44 with diabetic retinopathy and 87 without diabetic retinopathy). Retinography was performed with a Topcon TRC NW 200 non-mydriatic retinal camera. Using the Early Treatment of Diabetic Retinopathy Study Severity Scale, two independent observers graded the retinopathy. P...

  14. 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

    2015-01-01

    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. PMID:26314276

  15. Digital imaging-based retinal photocoagulation system

    Science.gov (United States)

    Barrett, Steven F.; Wright, Cameron H. G.; Oberg, Erik D.; Rockwell, Benjamin A.; Cain, Clarence P.; Rylander, Henry G., III; Welch, Ashley J.

    1997-05-01

    Researchers at the USAF Academy and the University of Texas are developing a computer-assisted retinal photocoagulation system for the treatment of retinal disorders (i.e. diabetic retinopathy, retinal tears). Currently, ophthalmologists manually place therapeutic retinal lesions, an acquired technique that is tiring for both the patient and physician. The computer-assisted system under development can rapidly and safely place multiple therapeutic lesions at desired locations on the retina in a matter of seconds. Separate prototype subsystems have been developed to control lesion depth during irradiation and lesion placement to compensate for retinal movement. Both subsystems have been successfully demonstrated in vivo on pigmented rabbits using an argon continuous wave laser. Two different design approaches are being pursued to combine the capabilities of both subsystems: a digital imaging-based system and a hybrid analog-digital system. This paper will focus on progress with the digital imaging-based prototype system. A separate paper on the hybrid analog-digital system, `Hybrid Retinal Photocoagulation System', is also presented in this session.

  16. Antioxidants and vascular health.

    Science.gov (United States)

    Bielli, Alessandra; Scioli, Maria Giovanna; Mazzaglia, Donatella; Doldo, Elena; Orlandi, Augusto

    2015-12-15

    Oxygen free radicals and other reactive oxygen species (ROS) are common products of normal aerobic cellular metabolism, but high levels of ROS lead to oxidative stress and cellular damage. Increased production of ROS favors vascular dysfunction, inducing altered vascular permeability and inflammation, accompanied by the loss of vascular modulatory function, the imbalance between vasorelaxation and vasoconstriction, and the aberrant expression of inflammatory adhesion molecules. Inflammatory stimuli promote oxidative stress generated from the increased activity of mitochondrial nicotinamide adenine dinucleotide phosphate oxidase, particularly of the Nox4 isoform, with the consequent impairment of mitochondrial β-oxidation. Vascular dysfunction due to the increase in Nox4 activity and ROS overproduction leads to the progression of cardiovascular diseases, diabetes, inflammatory bowel disease, and neurological disorders. Considerable research into the development of effective antioxidant therapies using natural derivatives or new synthetic molecules has been conducted. Antioxidants may prevent cellular damage by reducing ROS overproduction or interfering in reactions that involve ROS. Vitamin E and ascorbic acid are well known as natural antioxidants that counteract lipid peroxidative damage by scavenging oxygen-derived free radicals, thus restoring vascular function. Recently, preliminary studies on natural antioxidants such as goji berries, thymus, rosemary, green tea ginseng, and garlic have been conducted for their efficacy in preventing vascular damage. N-acetyl-cysteine and propionyl-L-carnitine are synthetic compounds that regulate ROS production by replacing endogenous antioxidants in both endothelial and smooth muscle cells. In this review, we consider the molecular mechanisms underlying the generation of oxidative stress-induced vascular dysfunction as well as the beneficial effects of antioxidant therapies. PMID:26585821

  17. Protein kinase C in porcine retinal arteries and neuroretina following retinal ischemia-reperfusion

    DEFF Research Database (Denmark)

    Gesslein, Bodil; Gustafsson, Lotta; Wackenfors, Angelica;

    2009-01-01

    Identification of the intracellular signal-transduction pathways activated in retinal ischemia may be important in revealing novel pharmacological targets. To date, most studies have focused on identifying neuroprotective agents. The retinal blood vessels are key organs in circulatory failure, an...

  18. Regulation of Taurine transporter activity in cultured rat retinal ganglion cells and rat retinal Muller Cells

    International Nuclear Information System (INIS)

    Diabetic retinopathy is one of the most common complications of diabetes. The amino acid taurine is believed to play an antioxidant protective role in diabetic retinopathy through the scavenging of the reactive species. It is not well established whether taurine uptake is altered in retina cells during diabetic conditions. Thus, the present study was designed to investigate the changes in taurine transport in cultures of rat retinal Muller cells and rat retinal ganglion cells under conditions associated with diabetes. Taurine was abundantly taken up by retinal Muller cells and rat retinal ganglion cells under normal glycemic condition. Taurine was actively transported to rat Muller cells and rat retinal ganglion cells in a Na and Cl dependant manner. Taurine uptake further significantly elevated in both type of cells after the incubation with high glucose concentration. This effect could be attributed to the increase in osmolarity. Because Nitric Oxide (NO) is a molecule implicated in the pathogenesis of diabetes, we also determined the activity of taurine transporter in cultured rat retinal Muller cells and rat retinal ganglion cells in the presence of the NO donors, SIN-1 and SNAP. Taurine uptake was elevated above control value after 24-h incubation with low concentration of NO donors. We finally investigated the ability of neurotoxic glutamate to change taurine transporter activity in both types of cells. Uptake of taurine was significantly increased in rat retinal ganglion cells when only incubated with high concentration of glutamate. Our data provide evidence that taurine transporter is present in cultured rat retinal ganglion and Muller cells and is regulated by hyperosmolarity. The data are relevant to disease such as diabetes and neuronal degeneration where retinal cell volume may dramatically change. (author)

  19. 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

  20. Effects of intravitreal injection of netrin-1 in retinal neovascularization of streptozotocin-induced diabetic rats

    Directory of Open Access Journals (Sweden)

    Yu Y

    2015-12-01

    Full Text Available Yao Yu,1,2,* Jing Zou,3,* Yun Han,4 Luowa Quyang,4 Hui He,4 Peihong Hu,2 Yi Shao,2 Ping Tu11Nanchang Key Laboratory of Diabetes, Department of Endocrinology and Metabolism, The Third Hospital of Nanchang, Jiangxi, People’s Republic of China; 2Department of Ophthalmology, The First Affiliated Hospital of Nanchang University, Jiangxi Province Clinical Ophthalmology Institute, Jiangxi, People’s Republic of China; 3Department of Ophthalmology, Xiangya Hospital, Central South University, Hunan, People’s Republic of China; 4Fujian Provincial Key Laboratory of Ophthalmology and Visual Science, Eye Institute of Xiamen University, Fujian, People’s Republic of China*These authors have contributed equally to this workBackground: In a previous study, we confirmed that netrin-1 acts as an antiangiogenic factor by inhibiting alkali burn-induced corneal neovascularization in rats. Here, we continue working on the role of netrin-1 in retinal neovascularization.Methods: Using an in vitro angiogenesis assay, we detected the effects of netrin-1 on human umbilical vein endothelial cell tube formation, viability and proliferation, migration, and invasion at concentrations of 0.1 µg/mL or 5 µg/mL. We intravitreally injected 0.1 µg/mL or 5 µg/mL netrin-1 into streptozotocin-induced rats to assess retinal neovascularization using retinal electrophysiology and electroretinography, enzyme-linked immunosorbent assay, fundus fluoresce in angiography, measurement of inner blood retinal barrier, retinal hematoxylin-eosin staining, and retinal flat-mount fluorescence assays.Results: Human umbilical vein endothelial cell tube formation, viability and proliferation, migration, and invasion were upregulated by netrin-1 at a concentration of 0.1 µg/mL (P<0.05, while 5 µg/mL netrin-1 had an opposite effect (P<0.05 in our in vitro angiogenesis assay. Retinal electrophysiology testing revealed that intravitreal injection of netrin-1 affected the amplitude of a- and b

  1. Toward high-resolution optoelectronic retinal prosthesis

    Science.gov (United States)

    Palanker, Daniel; Huie, Philip; Vankov, Alexander; Asher, Alon; Baccus, Steven

    2005-04-01

    It has been already demonstrated that electrical stimulation of retina can produce visual percepts in blind patients suffering from macular degeneration and retinitis pigmentosa. Current retinal implants provide very low resolution (just a few electrodes), while several thousand pixels are required for functional restoration of sight. We present a design of the optoelectronic retinal prosthetic system that can activate a retinal stimulating array with pixel density up to 2,500 pix/mm2 (geometrically corresponding to a visual acuity of 20/80), and allows for natural eye scanning rather than scanning with a head-mounted camera. The system operates similarly to "virtual reality" imaging devices used in military and medical applications. An image from a video camera is projected by a goggle-mounted infrared LED-LCD display onto the retina, activating an array of powered photodiodes in the retinal implant. Such a system provides a broad field of vision by allowing for natural eye scanning. The goggles are transparent to visible light, thus allowing for simultaneous utilization of remaining natural vision along with prosthetic stimulation. Optical control of the implant allows for simple adjustment of image processing algorithms and for learning. A major prerequisite for high resolution stimulation is the proximity of neural cells to the stimulation sites. This can be achieved with sub-retinal implants constructed in a manner that directs migration of retinal cells to target areas. Two basic implant geometries are described: perforated membranes and protruding electrode arrays. Possibility of the tactile neural stimulation is also examined.

  2. Deficiency of aldose reductase attenuates inner retinal neuronal changes in a mouse model of retinopathy of prematurity.

    Science.gov (United States)

    Fu, Zhongjie; Nian, Shen; Li, Suk-Yee; Wong, David; Chung, Sookja K; Lo, Amy C Y

    2015-09-01

    Retinopathy of prematurity (ROP) is a leading cause of childhood blindness where vascular abnormality and retinal dysfunction are reported. We showed earlier that genetic deletion of aldose reductase (AR), the rate-limiting enzyme in the polyol pathway, reduced the neovascularization through attenuating oxidative stress induction in the mouse oxygen-induced retinopathy (OIR) modeling ROP. In this study, we further investigated the effects of AR deficiency on retinal neurons in the mouse OIR. Seven-day-old wild-type and AR-deficient mice were exposed to 75 % oxygen for 5 days and then returned to room air. Electroretinography was used to assess the neuronal function at postnatal day (P) 30. On P17 and P30, retinal cytoarchitecture was examined by morphometric analysis and immunohistochemistry for calbindin, protein kinase C alpha, calretinin, Tuj1, and glial fibrillary acidic protein. In OIR, attenuated amplitudes and delayed implicit time of a-wave, b-wave, and oscillatory potentials were observed in wild-type mice, but they were not significantly changed in AR-deficient mice. The morphological changes of horizontal, rod bipolar, and amacrine cells were shown in wild-type mice and these changes were partly preserved with AR deficiency. AR deficiency attenuated the Müller cell gliosis induced in OIR. Our observations demonstrated AR deficiency preserved retinal functions in OIR and AR deficiency could partly reduce the extent of retinal neuronal histopathology. These findings suggested a therapeutic potential of AR inhibition in ROP treatment with beneficial effects on the retinal neurons. PMID:25921391

  3. Rod Photopigment Kinetics After Photodisruption of the Retinal Pigment Epithelium

    OpenAIRE

    Masella, Benjamin D.; Hunter, Jennifer J.; Williams, David R.

    2014-01-01

    Advances in retinal imaging have led to the discovery of disruption of the RPE caused by light exposures below published safety limits. To investigate the functional consequences of this RPE disruption, we combined adaptive optics ophthalmoscopy with retinal densitometry.

  4. 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...

  5. 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 ...

  6. The porcine retinal vasculature accessed using an endovascular approach

    DEFF Research Database (Denmark)

    Morén, Håkan; Undrén, Per; Gesslein, Bodil;

    2009-01-01

    The aim of this study was to examine whether the retinal circulation in the pig can be accessed using interventional neuroradiology and to explore the possibility of creating occlusions that result in experimental retinal ischemia....

  7. Neoplasia versus hyperplasia of the retinal pigment epithelium

    DEFF Research Database (Denmark)

    Heegaard, Steffen; Larsen, J.N.B.; Fledelius, Hans C.;

    2001-01-01

    ophthalmology, retinal pigment epithelium, adenoma, tumor-like hyperplasia, histology, immunohistochemistry, tumor, neoplasm, ultrasonography......ophthalmology, retinal pigment epithelium, adenoma, tumor-like hyperplasia, histology, immunohistochemistry, tumor, neoplasm, ultrasonography...

  8. 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.

  9. 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

  10. Lithium chloride protects retinal neurocytes from nutrient deprivation by promoting DNA non-homologous end-joining

    International Nuclear Information System (INIS)

    Lithium chloride is a therapeutic agent for treatment of bipolar affective disorders. Increasing numbers of studies have indicated that lithium has neuroprotective effects. However, the molecular mechanisms underlying the actions of lithium have not been fully elucidated. This study aimed to investigate whether lithium chloride produces neuroprotective function by improving DNA repair pathway in retinal neurocyte. In vitro, the primary cultured retinal neurocytes (85.7% are MAP-2 positive cells) were treated with lithium chloride, then cultured with serum-free media to simulate the nutrient deprived state resulting from ischemic insult. The neurite outgrowth of the cultured cells increased significantly in a dose-dependent manner when exposed to different levels of lithium chloride. Genomic DNA electrophoresis demonstrated greater DNA integrity of retinal neurocytes when treated with lithium chloride as compared to the control. Moreover, mRNA and protein levels of Ligase IV (involved in DNA non-homologous end-joining (NHEJ) pathway) in retinal neurocytes increased with lithium chloride. The end joining activity assay was performed to determine the role of lithium on NHEJ in the presence of extract from retinal neurocytes. The rejoining levels in retinal neurocytes treated with lithium were significantly increased as compared to the control. Furthermore, XRCC4, the Ligase IV partner, and the transcriptional factor, CREB and CTCF, were up-regulated in retinal cells after treating with 1.0 mM lithium chloride. Therefore, our data suggest that lithium chloride protects the retinal neural cells from nutrient deprivation in vitro, which may be similar to the mechanism of cell death in glaucoma. The improvement in DNA repair pathway involving in Ligase IV might have an important role in lithium neuroprotection. This study provides new insights into the neural protective mechanisms of lithium chloride.

  11. Long non-coding RNA MALAT1 regulates retinal neurodegeneration through CREB signaling.

    Science.gov (United States)

    Yao, Jin; Wang, Xiao-Qun; Li, Yu-Jie; Shan, Kun; Yang, Hong; Wang, Yang-Ning-Zhi; Yao, Mu-Di; Liu, Chang; Li, Xiu-Miao; Shen, Yi; Liu, Jing-Yu; Cheng, Hong; Yuan, Jun; Zhang, Yang-Yang; Jiang, Qin; Yan, Biao

    2016-01-01

    The nervous and vascular systems, although functionally different, share many common regulators of function maintenance. Long non-coding RNAs (lncRNAs) are important players in many biological processes and human disorders. We previously identified a role of MALAT1 in microvascular dysfunction. However, its role in neurodegeneration is still unknown. Here, we used the eye as the model to investigate the role of MALAT1 in retinal neurodegeneration. We show that MALAT1 expression is significantly up-regulated in the retinas, Müller cells, and primary retinal ganglion cells (RGCs) upon stress. MALAT1 knockdown reduces reactive gliosis, Müller cell activation, and RGC survival in vivo and in vitro MALAT1-CREB binding maintains CREB phosphorylation by inhibiting PP2A-mediated dephosphorylation, which leads to continuous CREB signaling activation. Clinical and animal experimentation suggests that MALAT1 dysfunction is implicated in neurodegenerative processes and several human disorders. Collectively, this study reveals that MALAT1 might regulate the development of retinal neurodegeneration through CREB signaling. PMID:26964565

  12. Associations of blood pressure variability and retinal arteriolar diameter in participants with type 2 diabetes.

    Science.gov (United States)

    Veloudi, Panagiota; Blizzard, Leigh; Srikanth, Velandai K; McCartney, Paul; Lukoshkova, Elena V; Hughes, Alun D; Head, Geoffrey A; Sharman, James E

    2016-07-01

    Blood pressure variability is associated with macrovascular complications and stroke, but its association with the microcirculation in type II diabetes has not been assessed. This study aimed to determine the relationship between blood pressure variability indices and retinal arteriolar diameter in non-diabetic and type II diabetes participants. Digitized retinal images were analysed to quantify arteriolar diameters in 35 non-diabetic (aged 52 ± 11 years; 49% male) and 28 type II diabetes (aged 61 ± 9 years; 50% male) participants. Blood pressure variability was derived from 24-h ambulatory blood pressure. Arteriolar diameter was positively associated with daytime rate of systolic blood pressure variation (p = 0.04) among type II diabetes participants and negatively among non-diabetics (p = 0.008; interaction p = 0.001). This finding was maintained after adjusting for age, sex, body mass index and mean daytime systolic blood pressure. These findings suggest that the blood pressure variability-related mechanisms underlying retinal vascular disease may differ between people with and without type II diabetes. PMID:27056406

  13. 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. PMID:22683799

  14. 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.

  15. Hesperidin Prevents Retinal and Plasma Abnormalities in Streptozotocin-Induced Diabetic Rats

    Directory of Open Access Journals (Sweden)

    Chunfeng Zhang

    2012-11-01

    Full Text Available Diabetic retinopathy is a complex disease that potentially involves increased production of advanced glycosylation end products (AGEs and elevated aldose reductase (AR activity, which are related with oxidative stress and inflammation. The aim of this study was to investigate the effects of hesperidin on retinal and plasma abnormalities in streptozotocin-induced diabetic rats. Hesperidin (100, 200 mg/kg daily was given to diabetic rats for 12 weeks. The blood-retina breakdown (BRB was determined after 2 weeks of treatment followed by the measurement of related physiological parameters with ELISA kits and immunohistochemistry staining at the end of the study. Elevated AR activity and blood glucose, increased retinal levels of vascular endothelial growth factor (VEGF, ICAM-1, TNF-α, IL-1β and AGEs as well as reduced retina thickness were observed in diabetic rats. Hesperidin treatment significantly suppressed BRB breakdown and increased retina thickness, reduced blood glucose, AR activity and retinal TNF-α, ICAM-1, VEGF, IL-1β and AGEs levels. Furthermore, treatment with hesperidin significantly reduced plasma malondialdehyde (MDA levels and increased SOD activity in diabetic rats. These data demonstrated that hesperidin attenuates retina and plasma abnormalities via anti-angiogenic, anti-inflammatory and antioxidative effects, as well as the inhibitory effect on polyol pathway and AGEs accumulation.

  16. Genetic linkage studies in autosomal recessive retinitis pigmentosa

    Energy Technology Data Exchange (ETDEWEB)

    Mansfield, D.C.; Teague, P.W.; Barber, A. [Western General Hospital, Edinburgh (United Kingdom)] [and others

    1994-09-01

    Autosomal recessive retinitis pigmentosa (arRP) is a severe retinal dystrophy characterized by night blindness, progressive constriction of the visual fields and loss of central vision in the fourth or fifth decades. The frequency of this form of retinitis pigmentosa (RP) varies in different populations. Mutations within the rhodopsin, cyclic GMP phosphodiesterase-{beta} subunit and cGMP-gated channel genes have been reported in some arRP families. The genetic loci responsible for the majority of cases have yet to be identified. Genetic heterogeneity is likely to be extensive. In order to minimize the amount of genetic heterogenity, a set of arRP families was ascertained within the South-Central Sardinian population, in which 81% of families with a known mode of inheritance show an autosomal recessive form of RP. The Sardinian population is an ethnic {open_quotes}outlier{close_quotes}, having remained relatively isolated from mainland and other cultures. Genetic linkage data has been obtained in a set of 11 Sardinian arRP kindreds containing 26 affected members. Under the assumption of genetic homogeneity, no evidence of linkage was found in the arRP kindreds using 195 markers, which excluded 62% of the genome (Z<-2). Positive lod scores were obtained with D14S80 which showed no recombination in a subset of 5 families. Heterogeneity testing using D14S80 and arRP showed no significant evidence of heterogeneity (p=0.18) but evidence of linkage ({chi}{sup 2}=3.64, p=0.028). We are currently screening the neural retina-specific leucine zipper gene (NRL) in 14q11 for mutations as a candidate locus.

  17. MR detection of retinal hemorrhages: correlation with graded ophthalmologic exam

    Energy Technology Data Exchange (ETDEWEB)

    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

  18. MR detection of retinal hemorrhages: correlation with graded ophthalmologic exam

    International Nuclear Information System (INIS)

    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

  19. Relation of Blood Pressure to Retinal Vessel Diameter in Type 1 Diabetes Mellitus

    Science.gov (United States)

    Klein, Ronald; Myers, Chelsea E.; Klein, Barbara E. K.; Zinman, Bernard; Gardiner, Robert; Suissa, Samy; Sinaiko, Alan R.; Donnelly, Sandra M.; Goodyer, Paul; Strand, Trudy; Mauer, Michael

    2009-01-01

    Objective To examine the relationship of blood pressure (BP) and use of angiotensin receptor blocker (ARB) or angiotensin converting enzyme inhibitor (ACEI) to retinal vessel diameter in normotensive, normoalbuminuric persons with type 1 diabetes mellitus (T1DM). Design Randomized controlled clinical trial. Participants Persons with T1DM and gradable fundus photographs both at baseline (n=147) and 5-year follow-up (n=124). Methods Clinic and 24-hour ambulatory BPs (ABP) were measured. Retinal arteriolar and venular diameters were measured using a computer-assisted technique. Individual arteriolar and venular measurements were combined into summary indices that reflect the average retinal arteriolar (central retinal arteriolar equivalent [CRAE]) and venular (central retinal venular equivalent [CRVE]) diameter of an eye, respectively. Main Outcome Measures CRAE and CRVE. Results While controlling for age, study site, glycosylated hemoglobin and ambulatory pulse rate, daytime ambulatory systolic (-0.29 μm effect per 1mmHg, P=.02) and daytime ambulatory diastolic (-0.44 μm effect per 1mmHg, P=.04), nighttime ambulatory systolic (-0.27 μm effect per 1mmHg, P=.03), and 24-hour ambulatory systolic BP (-0.31 μm effect per 1mmHg, P=.03) were cross-sectionally associated with a smaller CRAE. While controlling for age, study site, glycosylated hemoglobin, ambulatory pulse rate and baseline CRAE, no BP measure was associated with a change in CRAE or CRVE over 5 years of follow-up. Treatment with losartan or enalapril was not associated with a statistically significant change in CRAE or CRVE. Conclusions ACEI or ARB therapy does not affect retinal arteriolar or venular diameter in normotensive persons with T1DM. PMID:20142543

  20. Rapid glutamate receptor 2 trafficking during retinal degeneration

    OpenAIRE

    Lin Yanhua; Jones Bryan W; Liu Aihua; Vazquéz-Chona Félix R; Lauritzen J Scott; Ferrell W Drew; Marc Robert E

    2012-01-01

    Abstract Background Retinal degenerations, such as age-related macular degeneration (AMD) and retinitis pigmentosa (RP), are characterized by photoreceptor loss and anomalous remodeling of the surviving retina that corrupts visual processing and poses a barrier to late-stage therapeutic interventions in particular. However, the molecular events associated with retinal remodeling remain largely unknown. Given our prior evidence of ionotropic glutamate receptor (iGluR) reprogramming in retinal ...