5
views
0
recommends
+1 Recommend
1 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Vitrectomia farmacológica e descolamento do vítreo posterior Translated title: Pharmacological vitreolysis and posterior vitreous detachment

      other

      Read this article at

      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          O vítreo exerce papel crucial na patogênese de vários distúrbios vitreoretinianos. As alterações moleculares e estruturais fisiológicas do gel vítreo evoluem para a liquefação e culminam com o descolamento do córtex vítreo posterior (DVP). A ocorrência do descolamento do vítreo posterior influencia positivamente o prognóstico de pacientes diabéticos, com maculopatias e vasculopatias. Abordaremos o conceito da vitrectomia farmacológica que se refere ao uso de agentes que alteram a organização molecular do vítreo, num esforço de reduzir ou eliminar seu papel na gênese de doenças vítreo-retinianas, sendo o seu objetivo final, o descolamento total do vítreo posterior. Vários agentes têm sido estudados durante a última década, porém, existem várias limitações na aplicabilidade clínica destes compostos. Nesse artigo de revisão, iremos abordar os diferentes agentes e os seus mecanismos de ação sobre a matriz extracelular e a interface vítreo-retiniana.

          Translated abstract

          The vitreous plays an important role in the pathogenesis of several vitreoretinal diseases. The physiological molecular and structural modifications of the vitreous gel lead to liquefaction and posterior vitreous detachment, which positively influence the vision of patients with diabetic retinopathy, maculopathies and vasculopathies. This review article will approach the concept of pharmacological vitreolysis that refers to the use of different agents, which modify the molecular vitreous organization, in order to reduce or eliminate its role in the genesis of several vitreoretinal diseases, having a posterior vitreous detachment as its final goal. In the last decade, several agents have been extensively studied but there are some limitations in their clinical applicability. We will discuss such agents and their effects on different sites of the vitreoretinal extracellular matrix and vitreoretinal interface.

          Related collections

          Most cited references27

          • Record: found
          • Abstract: found
          • Article: not found

          Integrins as mechanochemical transducers.

          D. Ingber (1991)
          A recent resurgence of interest in mechanical forces and cell shape as biological regulators has revealed extracellular matrix as the site at which forces are transmitted both to and from cells. at the same time, great advances have been made in terms of defining cell-surface integrin receptors as transmembrane molecules that mediate cell attachment and physically interlink extracellular matrix with the intracellular cytoskeleton. Convergence of these two lines of research has begun to elucidate the molecular mechanism by which cells sense physical forces and transduce mechanical signals into a biochemical response.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Influence of stereochemistry of the sequence Arg-Gly-Asp-Xaa on binding specificity in cell adhesion.

            Peptides containing the tripeptide sequence Arg-Gly-Asp can duplicate or inhibit the cell attachment-promoting effects of fibronectin and vitronectin. Peptides analogous to a prototype peptide, Gly-Arg-Gly-Asp-Ser-Pro-Cys, the sequence of which was taken from the cell attachment site of fibronectin, were assayed for their relative abilities to inhibit the attachment of cells to a fibronectin or vitronectin substrate. A peptide having the L-Arg residue replaced with D-Arg showed no difference in this capacity, whereas substituting Gly with D-Ala or L-Asp with D-Asp resulted in completely inactive peptides. Replacement of L-Ser with D-Ser drastically reduced the influence that the resulting peptide had on the vitronectin interaction, but this peptide showed little difference in its effect on the binding of cells to fibronectin when compared with the prototype peptide. Furthermore, substitution of the Ser with L-Asn resulted in a peptide that had an apparent increased preference for the fibronectin receptor and decreased preference for the vitronectin receptor. Conversely, threonine in this position gave a peptide with increased preference for the vitronectin receptor, whereas L-Pro in this position gave a completely inactive peptide. Finally, by cyclicizing the prototype peptide to restrict its conformational flexibility, a peptide was obtained that was a much improved inhibitor of attachment of cells to vitronectin and yet nearly inactive with respect to the interactions of cells with fibronectin substrates. These studies lend support to the hypothesis that different Arg-Gly-Asp-directed adhesion receptors can recognize differences in the conformation and environment of the Arg-Gly-Asp tripeptide, and they establish the feasibility of obtaining synthetic probes that are more selective for individual receptors than are the peptides modeled after the natural sequences of adhesive extracellular matrix molecules.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Optical coherence tomography of the vitreoretinal interface in macular hole formation.

              To image the vitreoretinal interface and provide further information on the pathogenesis of idiopathic macular hole formation. Prospective recruitment of 80 eyes of 41 consecutive patients referred with a diagnosis of idiopathic full thickness macular hole (FTMH) to a teaching hospital retinal clinic. Both eyes of each patient underwent optical coherence tomography (OCT) imaging with vertical and horizontal scans centred on the fovea. A total of 30 eyes had stage 2 or 3 FTMHs and, of these, 21 had persistent vitreofoveal attachment and associated prefoveal opacities. 18 prefoveal opacities were identified by Goldmann contact lens examination and confirmed on OCT examination. Three prefoveal opacities were identified only on OCT examination. 10 eyes had stage 4 FTMHs and four cases were identified in whom the OCT appearance was consistent with impending, aborted, or lamellar macular holes. The wide range in OCT appearance of macular holes and associated prefoveal opacities suggests that, in at least some cases, a significant amount of retinal tissue is torn from the foveal area during macular hole formation. OCT imaging provides additional information on macular hole pathogenesis and is valuable in the planning of surgical intervention.
                Bookmark

                Author and article information

                Journal
                abo
                Arquivos Brasileiros de Oftalmologia
                Arq. Bras. Oftalmol.
                Conselho Brasileiro de Oftalmologia (São Paulo, SP, Brazil )
                0004-2749
                1678-2925
                December 2004
                : 67
                : 6
                : 973-976
                Affiliations
                [01] orgnameUniversidade de São Paulo orgdiv1Faculdade de Medicina de Ribeirão Preto
                [02] orgnameUniversidade de São Paulo orgdiv1Faculdade de Medicina de Ribeirão Preto orgdiv2Departamento de Oftalmologia, Otorrinolaringologia e Cirurgia de Cabeça e Pescoço
                [03] orgnameUniversidade de São Paulo orgdiv1Faculdade de Medicina de Ribeirão Preto orgdiv2Hospital das Clínicas
                Article
                S0004-27492004000600026 S0004-2749(04)06700626
                22ee77d8-ffed-42c3-94c4-19acac054270

                This work is licensed under a Creative Commons Attribution 4.0 International License.

                History
                : 11 October 2004
                : 06 October 2004
                Page count
                Figures: 0, Tables: 0, Equations: 0, References: 28, Pages: 4
                Product

                SciELO Brazil

                Categories
                Atualização Continuada

                Vitreous detachment,Vitrectomy,Doenças retinianas,Retinal diseases,Extracellular matrix,Vitreous body,Matriz extracelular,Corpo vítreo,Descolamento do vítreo,Vitrectomia

                Comments

                Comment on this article