O comprometimento macular na retinopatia diabética pode ocorrer devido a isquemia macular, hemorragias maculares intra-retinianas e pré-retinianas, descolamento macular tracional, neovascularização e mais freqüentemente o edema macular. Cerca de 10% da população total de pacientes com diabete melito (DM) e 25% daqueles com mais de 20 anos de evolução da doença apresentam edema macular, constituindo a principal causa de perda visual neste grupo de pacientes(1-3). Em pacientes com DM tipo 1, o edema macular é visto raramente antes dos primeiros nove anos após o diagnóstico de DM(4), ao contrário de pacientes diabéticos tipo 2 cujo início da maculopatia é mais precoce. A detecção e o tratamento precoce do edema macular podem resultar na melhora ou na estabilização da visão. Novas teorias sobre a fisiopatologia do edema macular surgiram nos últimos anos e novas terapias como a triancinolona sub-tenoneana ou intravítrea, os anti-VEGFs e implantes intravítreos de liberação lenta de dexametasona foram testadas a partir destes conhecimentos. Este manuscrito propõe a revisão destes conceitos e em especial, dos novos aspectos terapêuticos. / The macular commitment on diabetic retinopathy can occur due to macular ischaemia, intraretinal or preretinal haemorrhages, tractional detachment, neovascularization and more frequently, macular edema. About 10% of the diabetic population and 25% of those with more than 20 years of illness, present macular edema, constituting the main cause of visual loss in this group of patients (1-3). In diabetic type 1 patients, macular edema is rarely seen before 9 years after the diagnostic(4). On the other hand, in diabetic type 2 patients, the maculopathy appears earlier. The detection and the precocious treatment of macular edema can result a visual improvement or stabilization. New theories about the fisiopathology of macular edema had appeared in the last years and new therapies such as sub-tenonean or intravitreal triamcinolone, the anti- VEGFs and slow liberation intravitreal implants of dexametazone were tested since this knowledge. This article considers the revision of these concepts and specially, new therapeutic aspects.

Dissertação (mestrado) - Pontifícia Universidade Católica do Paraná, Curitiba, 2012 / Bibliografia: f. 53-63 / A degeneração macular relacionada à idade (DMRI) é uma doença ocular degenerativa. Alguns dos fatores causais desta doença são compartilhados pela doença aterosclerótica, sendo a origem de ambas relacionadas à alterações inflamatórias. OBJETIVO: avaliar, / Age-related macular degeneration (AMD) is a degenerative eye disease. Some of the causal factors of this disease are common to atherosclerotic diseases and the origin of both diseases is related to inflammatory changes. OBJECTIVE: To evaluate by histomorp

Dissertação (mestrado) - Pontifícia Universidade Católica do Paraná, Curitiba, 2012 / Bibliografia: f. 50-59 / O presente trabalho teve por objetivo investigar os principais efeitos da linhaça na retina, coróide e esclera de coelhos submetidos à dieta hipercolesterolêmica. A metodologia de trabalho que norteou a pesquisa observou os passos a seguir. Coelhos New Ze / The present study aims to investigate the main flaxseed effects on the retina, choroid and sclera of rabbits fed on a hypercholesterolemic diet. The research methodology was grounded on the following procedures. New Zealand rabbits were divided into three

In vitro disease models are powerful platforms for the development of drugs and novel therapies. Stem-cell based approaches have emerged as cutting-edge tools in disease modelling, allowing for deeper insights into previously unknown disease mechanisms. Hence the significant role of these disease-in-a-dish methods in therapeutics and translational medicine. Impedance sensing is a non-invasive, quantitative technique that can monitor changes in cellular behaviour and morphology in real-time. Bioimpedance measurements can be used to characterize and evaluate the establishment of a valid disease model, without the need for invasive end-point biochemical assays. In this work, two stem cell-based disease models-on-a-chip are proposed for acute liver failure (ALF) and age-related macular degeneration (AMD). The ALF disease model-on-a-chip integrates impedance sensing with the highly-differentiated HepaRG cell line to monitor in real-time quantitative and dynamic response to various hepatotoxins. Bioimpedance analysis and modelling has revealed an unknown mechanism of paracetamol hepatotoxicity; a temporal, dose-dependent disruption of tight junctions (TJs) and cell-substrate adhesion. This disruption has been validated using ultrastructural imaging and immunostaining of the TJ-associated protein ZO-1. Age-related macular degeneration (AMD) is the leading cause of blindness in the developed world with a need for disease models for its currently incurable forms. Human induced pluripotent stem cells (hiPSCs) technology offers a novel approach for disease modelling, with the potential to impact translational retinal research and therapy. Recent developments enable the generation of Retinal Pigment Epithelial cells from patients (hiPSC-RPE), thus allowing for human retinal disease in vitro studies with great clinical and physiological relevance. In the current study, the development of a tissue-on- a-chip AMD disease model has been established using RPE generated from a patient with an inherited macular degeneration (case cell line) and from a healthy sibling (control cell line). A reproducible Electric Cell-substrate Impedance Sensing (ECIS) electrical wounding assay was conducted to mimic RPE damage in AMD. First, a robust and reproducible real-time quantitative monitoring over a 25-day period demonstrated the establishment and maturation of RPE layers on microelectrodes. A spatially-controlled RPE layer damage that mimicked cell loss in AMD was then initiated. Post recovery, significant differences in migration rates were found between case and control cell lines. Data analysis and modelling suggested this was due to the lower cell-substrate adhesion of the control cell line. These findings were confirmed using cell adhesion biochemical assays. Moreover, different-sized, individually-addressed square microelectrode arrays with high spatial resolution were designed and fabricated in-house. ECIS wounding assays were performed on these chips to study immortalized RPE migration. Migration rates comparable to those obtained with ECIS circular microelectrodes were determined. The two proposed disease-models-on-a-chip were then used to explore the therapeutic potential of the antioxidant N-Acetyl-Cysteine (NAC) on hiPSC-RPE and HepaRG cell recovery. Addition of 10 mM NAC at the end of a 24h paracetamol challenge caused a slight increase in the measured impedance, suggesting partial cell recovery. On the other hand, no effect on case hiPSC-RPE migration has been observed. More experiments are needed to examine the effect of different NAC concentrations and incubation periods. The therapeutic potential of electrical stimulation has also been explored. A preliminary study to evaluate the effect of electrical stimulation on RPE migration has been conducted. An externally applied direct current electric field (DC EF) of 300 mV/mm was found to direct the migration of the immortalized RPE cell line (hTERT-RPE1) perpendicular to the EF. The cells were also observed to elongate and to realign their long axes perpendicular to the applied EF. The proposed tissue-on-a-chip disease models are powerful platforms for translational studies. The potential of such platforms has been demonstrated through revealing unknown effects of acetaminophen on the liver as well as providing deeper insights into the underlying mechanisms of macular degeneration. Combining stem cell technology with impedance sensing provides a high throughput platform for studying patient-specific diseases and evaluating potential therapies.

1 Abstract Introduction The vitreoretinal (VR) interface of the eye is a dynamically evolving environment which significantly influences and indicates the course of macular disorders. The main topic of the presented paper is research on the VR interface in relation to surgery on diabetic macular edema (ME), partial macular defects (PMD) and idiopathic macular holes (IMH). Aims The aims of the research were to find out new knowledge about specific characteristics of and changes in the VR interface in eyes with diabetic ME, PMD and IMH, namely with main attention focused on the internal limiting membrane (ILM) of the retina and the epimacular membrane (EMM). Methods Histopathologic and morphometric analyses were carried out on samples of the ILM of the retina and the EMM which were taken during pars plana vitrectomy (PPV) of eyes of sets of patients with diabetic ME, PMD and IMH. The analytic results were statistically evaluated and interpreted in relation to clinical factors and anatomical results of the PPV. Results Treatment of diabetic ME with removal of the ILM resulted in improved visual acuity (VA), at minimum 2 lines on the ETDRS table, in 51.8% surgically treated eyes and remained the same in 33.9% of eyes. A comparison study confirmed that PPV with preserving of the ILM achieved a long-term...

O comprometimento macular na retinopatia diabética pode ocorrer devido a isquemia macular, hemorragias maculares intra-retinianas e pré-retinianas, descolamento macular tracional, neovascularização e mais freqüentemente o edema macular. Cerca de 10% da população total de pacientes com diabete melito (DM) e 25% daqueles com mais de 20 anos de evolução da doença apresentam edema macular, constituindo a principal causa de perda visual neste grupo de pacientes(1-3). Em pacientes com DM tipo 1, o edema macular é visto raramente antes dos primeiros nove anos após o diagnóstico de DM(4), ao contrário de pacientes diabéticos tipo 2 cujo início da maculopatia é mais precoce. A detecção e o tratamento precoce do edema macular podem resultar na melhora ou na estabilização da visão. Novas teorias sobre a fisiopatologia do edema macular surgiram nos últimos anos e novas terapias como a triancinolona sub-tenoneana ou intravítrea, os anti-VEGFs e implantes intravítreos de liberação lenta de dexametasona foram testadas a partir destes conhecimentos. Este manuscrito propõe a revisão destes conceitos e em especial, dos novos aspectos terapêuticos. / The macular commitment on diabetic retinopathy can occur due to macular ischaemia, intraretinal or preretinal haemorrhages, tractional detachment, neovascularization and more frequently, macular edema. About 10% of the diabetic population and 25% of those with more than 20 years of illness, present macular edema, constituting the main cause of visual loss in this group of patients (1-3). In diabetic type 1 patients, macular edema is rarely seen before 9 years after the diagnostic(4). On the other hand, in diabetic type 2 patients, the maculopathy appears earlier. The detection and the precocious treatment of macular edema can result a visual improvement or stabilization. New theories about the fisiopathology of macular edema had appeared in the last years and new therapies such as sub-tenonean or intravitreal triamcinolone, the anti- VEGFs and slow liberation intravitreal implants of dexametazone were tested since this knowledge. This article considers the revision of these concepts and specially, new therapeutic aspects.

O comprometimento macular na retinopatia diabética pode ocorrer devido a isquemia macular, hemorragias maculares intra-retinianas e pré-retinianas, descolamento macular tracional, neovascularização e mais freqüentemente o edema macular. Cerca de 10% da população total de pacientes com diabete melito (DM) e 25% daqueles com mais de 20 anos de evolução da doença apresentam edema macular, constituindo a principal causa de perda visual neste grupo de pacientes(1-3). Em pacientes com DM tipo 1, o edema macular é visto raramente antes dos primeiros nove anos após o diagnóstico de DM(4), ao contrário de pacientes diabéticos tipo 2 cujo início da maculopatia é mais precoce. A detecção e o tratamento precoce do edema macular podem resultar na melhora ou na estabilização da visão. Novas teorias sobre a fisiopatologia do edema macular surgiram nos últimos anos e novas terapias como a triancinolona sub-tenoneana ou intravítrea, os anti-VEGFs e implantes intravítreos de liberação lenta de dexametasona foram testadas a partir destes conhecimentos. Este manuscrito propõe a revisão destes conceitos e em especial, dos novos aspectos terapêuticos. / The macular commitment on diabetic retinopathy can occur due to macular ischaemia, intraretinal or preretinal haemorrhages, tractional detachment, neovascularization and more frequently, macular edema. About 10% of the diabetic population and 25% of those with more than 20 years of illness, present macular edema, constituting the main cause of visual loss in this group of patients (1-3). In diabetic type 1 patients, macular edema is rarely seen before 9 years after the diagnostic(4). On the other hand, in diabetic type 2 patients, the maculopathy appears earlier. The detection and the precocious treatment of macular edema can result a visual improvement or stabilization. New theories about the fisiopathology of macular edema had appeared in the last years and new therapies such as sub-tenonean or intravitreal triamcinolone, the anti- VEGFs and slow liberation intravitreal implants of dexametazone were tested since this knowledge. This article considers the revision of these concepts and specially, new therapeutic aspects.

Made available in DSpace on 2014-06-12T18:28:59Z (GMT). No. of bitstreams: 2 arquivo3535_1.pdf: 4497210 bytes, checksum: aa2e672b4d17f24b8c8446cc122032b6 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2009 / A hipomelanose macular progressiva é uma dermatose caracterizada por máculas hipocrômicas localizadas principalmente em tronco, que tendem a confluir na linha média. Em pacientes melanodérmicos, as lesões contrastam com a pele normal prejudicando a auto-estima dos pacientes. Sua etiologia permanece especulativa, sendo sugerida a participação do Propionibacterium acnes, um membro da flora cutânea normal. Objetivo: Avaliar a presença do Propionibacterium acnes na pele lesional e não lesional de pacientes com hipomelanose macular progressiva, por meio da reação em cadeia da polimerase em tempo real quantitativa e cultura bacteriológica de fragmento de pele e, determinar o ponto de corte para o número de cópias de genoma de Propionibacterium acnes, como marcador de sua positividade na pele lesional de pacientes com hipomelanose macular progressiva, utilizando a reação em cadeia da polimerase em tempo real quantitativa e considerando a cultura como padrão-ouro. Pacientes e Métodos: Estudo exploratório, observacional com grupo de comparação foi realizado envolvendo 36 pacientes, atendidos nos ambulatórios de dermatologia do Hospital Universitário Oswaldo Cruz, Recife, Pernambuco, Brasil, entre março e maio de 2008. Todos os pacientes foram submetidos a exame sob luz de Wood, pesquisa micológica e biópsias de pele lesional e não lesional do dorso. Os fragmentos de biópsia de pele foram submetidos a exame histopatológico, cultura bacteriológica e reação em cadeia da polimerase em tempo real quantitativa, utilizando oligoiniciadores específicos para a região 16S do RNA ribossomal do Propionibacterium acnes. A pele lesional foi comparada a não lesional quanto à positividade da reação em cadeia da polimerase em tempo real quantitativa e da cultura, considerada padrão-ouro. Com o programa Statistical Package for Social Sciences, versão 12.0, procedeu-se à determinação de associação com os testes de Wilcoxon e de McNemar, em nível de significância de 0,05, e do ponto de corte com a curva ROC para valores máximos. Resultados: Houve predomínio significante do Propionibacterium acnes na pele lesional, comparada com a pele não lesional (p<0,001), demonstrado por cultura bacteriológica e reação em cadeia da polimerase em tempo real quantitativa. O ponto de corte para o número de cópias de genoma de Propionibacterium acnes como marcador de sua positividade na pele lesional de pacientes com hipomelanose macular progressiva igualou-se a 1.333, com sensibilidade de 87,9% e especificidade de 100,0%. Conclusão: Apesar do Propionibacterium acnes ser um saprófita do folículo pilossebáceo, ele esta mais presente em pele lesional dos pacientes com hipomelanose macular progressiva, sugerindo sua participação no desenvolvimento dessa dermatose

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L’œdème maculaire est une complication majeure de nombreuses pathologies rétiniennes induisant la cécité. Les traitements actuels ne sont pas curatifs. Ce sont des injections intraoculaires de corticostéroïdes et d'anti-VEGF. Les mécanismes d'action de ces médicaments sont mal connus dans l'œil car ces thérapies ont été initialement développées pour des pathologies non-oculaires (tels que l'asthme et les maladies auto-immunes pour les corticostéroïdes et les cancers pour certains anti-VEGF). De plus, les effets bénéfiques de ces molécules sont contrebalancés par des effets secondaires graves (glaucomes et cataractes pour les corticostéroïdes) et la résistance au traitement. Le projet vise à élucider les mécanismes d'action oculaires des corticostéroïdes et anti-VEGF; dans le but d'identifier de nouvelles cibles thérapeutiques pour le traitement de l’œdème maculaire. Ce travail a porté sur : 1) La compréhension des mécanismes des corticostéroïdes et de leurs récepteurs (le récepteur aux glucocorticoïdes ou GR et le récepteur aux minéralocorticoïdes ou MR) suite à l’injection intravitréene de corticostéroïdes ou d’aldostérone chez le rat. Nous avons ainsi : -1.1. Identifier les protéines partenaires du GR et du MR avant et après traitements par une approche protéomique (immunoprécipitations endogènes suivies d’une analyse par spectrométrie de masse). -1.2. Identification les gènes cibles dont l'expression est modulée par les corticostéroïdes ou l’aldostérone par ARN-sequencing. 2) L'identification des mécanismes d’action des aux anti-VEGFs et leur comparaison avec des molécules de même nature physico-chimique. 3) L’identification des gènes différentiellement exprimés entre la rétine périphérique et la macula (zone d’acuité visuelle susceptible à la formation d’œdèmes) chez le singe (modèle qui possède, comme l’homme, une macula). Ceci afin de comprendre pourquoi la macula est particulièrement sensible. 4) L’analyse et la comparaison de ces différents traitements. Ces études ont permis d’identifier les cofacteurs des récepteurs aux corticostéroïdes, ainsi que la dynamique de leurs interactions avant et après traitement à la corticostérone et à l’aldostérone; ainsi que les gènes dont l’expression est régulée par les corticostéroïdes et les anti-VEGF. L’analyse croisée des données, des analyses bioinformatiques ainsi que l’étude bibliographique des protéines et gènes identifiés nous ont permis d’établir une liste restreinte de cibles potentielles des traitements anti-œdémateux, dans le but final de potentialiser l’effet de ces traitements, trop souvent associés à des effets secondaires qui limitent considérablement leur(s) action(s) bénéfique(s) sur la fonction visuelle dans le traitement de l’œdème maculaire. / Macular Edema is a major complication of numerous retinal pathologies that lead the blindness. The available treatments (intra-ocular injection of corticosteroids and anti-VEGF) do not cure this disease. The ocular mechanisms of action of these drugs are not very well understood. In fact, these molecules have been initially developed for non-ocular pathologies, such as asthma, auto-immune diseases (for corticosteroid) and cancers (for anti-VEGF). In addition, the beneficial effects of these drugs are counteracted by their side effects (cataracts and glaucoma for corticosteroids) as well as resistance to treatment. The project aims at unraveling the ocular mechanisms of action of corticosteroids and anti-VEGF; in order to identify new therapeutic targets for the treatment of macular edema. The project focused on: 1) The understanding of the mechanisms of the corticosteroids and their receptors after an intravitreal injection of Corticosterone or Aldosterone in the rat model. We therefore: 1.1. Identified the partner proteins of the glucocorticoid and mineralocorticoid receptors before and after treatment, using a proteomic approach. 1.2. Identified the target genes which expression is modulated by the corticosteroid using the RNA-Sequencing technique. 2) The identification of the mechanisms of action of anti-VEGF molecules and their comparison with molecules that have similar physico-chemical structure. 3) The identification of differentially expressed genes between the retina and the macula in the monkey model. This aimed at understanding why the macula is particularly sensitive to edemas. 4) The analysis and comparison of these treatments. We were able to identify co-factors for corticosteroids receptors as well as the dynamics of these interactions (before and after treatment), as well as the genes which expression is regulated by the corticosteroids or anti-VEGF. The analysis of the bio-informatic data as well as the bibliographic study of the identified proteins and genes allowed us to establish a list of partiMacularly interesting genes that are potentially therapeutic targets for the treatment of macular edema.