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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
191

Estudo comparativo entre o telescópio com lente de contato e o telescópio convencional em pacientes com baixa visão / Comparative study between contact lens telescope and conventional telescope in lowvision patients

Bellini, Luciano Porto January 2009 (has links)
Objetivos: comparar o telescópio com lente de contato (TLC) com o telescópio convencional (TC) em pacientes com degeneração macular relacionada à idade (DMRI) e baixa visão, com respeito a: acuidade visual (AV), campo de visão (CV), satisfação do paciente com a visão oferecida pelo telescópio (SV), dificuldade de uso do telescópio (DU) e satisfação do paciente com o aspecto estético do telescópio (SE). Materiais e Métodos: Em ensaio clínico randomizado mascarado, foram incluídos 12 pacientes com DMRI e baixa visão, formando 2 grupos de 6 pacientes cada: grupo 1 (uso de TLC) e grupo 2 (uso de TC). Os telescópios usados no estudo foram padronizados para que tivessem a mesma magnificação (2,8x). A AV e o CV foram aferidos antes e durante o uso do telescópio, enquanto a SV, a DU e a SE foram obtidas após a intervenção. Resultados: Não houve diferenças entre os grupos na linha de base. Os dois telescópios demonstraram melhora da AV em relação à linha de base (P=0,002 com o TLC e P<0,001 com o TC) e não houve diferença entre os grupos a este respeito. O CV foi reduzido em 15° com o TLC (P<0.001) e em 54.3° com o TC (P<0.001), em comparação com a linha de base, e tais diferenças também foram significativas entre os grupos durante a intervenção (P<0.001). Os escores de SV foram semelhantes entre os grupos testados. Já os escores de SE, foram maiores com o TLC (P<0.001), assim como os de DU (P=0.003), em relação ao TC. Conclusões: Os dois telescópios promoveram melhora semelhante da AV em pacientes com DMRI e baixa visão, mas o TLC acarretou menor perda de CV em relação ao TC. A SE foi maior com o TLC, mas a DU também foi maior com o TLC, em relação ao TC. / Purpose: To compare the conventional telescope (CT) with the contact lens telescope (CLT) in patients with age-related macular degeneration (AMD) and low-vision, with respect to visual acuity (VA), visual field (VF), patient satisfaction with the vision provided by the telescope (VS), telescope use difficulties (UD) and patient satisfaction with the cosmetic appearance of the telescope (CS). Methods: In a masked randomized clinical trial, 12 patients with AMD and low-vision were enrolled in 2 groups with 6 patients each: group 1 (CLT use) and group 2. (CT use) The telescopes used in this study were standardized to have the same magnification power. (2.8x) Visual field and VA were obtained before and during the telescope use, while VS, UD and CS were obtained after the telescope use. Results: There were no significant differences between groups at baseline. Both groups achieved VA improvement with telescopes compared to baseline (P=0.002 in CLT group and P<0.001 in CT group) and there were no significant differences between groups in this regard. Visual field was reduced by 15° in CLT group (P<0.001) and by 54.3° in CT group (P<0.001) compared to baseline, and VF differences between groups were also significant during telescope use. (P<0.001) Scores observed in both groups were similar in regard to VS. Telescope use difficulties were significant higher in CLT group (P=0.003) as well as CS scores (P<0.001) compared to CT group. Conclusions: Both telescopes provide similar improvement in VA in AMD patients with low-vision, but CLT caused less VF reduction than CT use. Patient satisfaction with the cosmetic appearance of the telescope was higher in CLT group, but UD was also higher in this group compared to CT group.
192

Estudo comparativo entre o telescópio com lente de contato e o telescópio convencional em pacientes com baixa visão / Comparative study between contact lens telescope and conventional telescope in lowvision patients

Bellini, Luciano Porto January 2009 (has links)
Objetivos: comparar o telescópio com lente de contato (TLC) com o telescópio convencional (TC) em pacientes com degeneração macular relacionada à idade (DMRI) e baixa visão, com respeito a: acuidade visual (AV), campo de visão (CV), satisfação do paciente com a visão oferecida pelo telescópio (SV), dificuldade de uso do telescópio (DU) e satisfação do paciente com o aspecto estético do telescópio (SE). Materiais e Métodos: Em ensaio clínico randomizado mascarado, foram incluídos 12 pacientes com DMRI e baixa visão, formando 2 grupos de 6 pacientes cada: grupo 1 (uso de TLC) e grupo 2 (uso de TC). Os telescópios usados no estudo foram padronizados para que tivessem a mesma magnificação (2,8x). A AV e o CV foram aferidos antes e durante o uso do telescópio, enquanto a SV, a DU e a SE foram obtidas após a intervenção. Resultados: Não houve diferenças entre os grupos na linha de base. Os dois telescópios demonstraram melhora da AV em relação à linha de base (P=0,002 com o TLC e P<0,001 com o TC) e não houve diferença entre os grupos a este respeito. O CV foi reduzido em 15° com o TLC (P<0.001) e em 54.3° com o TC (P<0.001), em comparação com a linha de base, e tais diferenças também foram significativas entre os grupos durante a intervenção (P<0.001). Os escores de SV foram semelhantes entre os grupos testados. Já os escores de SE, foram maiores com o TLC (P<0.001), assim como os de DU (P=0.003), em relação ao TC. Conclusões: Os dois telescópios promoveram melhora semelhante da AV em pacientes com DMRI e baixa visão, mas o TLC acarretou menor perda de CV em relação ao TC. A SE foi maior com o TLC, mas a DU também foi maior com o TLC, em relação ao TC. / Purpose: To compare the conventional telescope (CT) with the contact lens telescope (CLT) in patients with age-related macular degeneration (AMD) and low-vision, with respect to visual acuity (VA), visual field (VF), patient satisfaction with the vision provided by the telescope (VS), telescope use difficulties (UD) and patient satisfaction with the cosmetic appearance of the telescope (CS). Methods: In a masked randomized clinical trial, 12 patients with AMD and low-vision were enrolled in 2 groups with 6 patients each: group 1 (CLT use) and group 2. (CT use) The telescopes used in this study were standardized to have the same magnification power. (2.8x) Visual field and VA were obtained before and during the telescope use, while VS, UD and CS were obtained after the telescope use. Results: There were no significant differences between groups at baseline. Both groups achieved VA improvement with telescopes compared to baseline (P=0.002 in CLT group and P<0.001 in CT group) and there were no significant differences between groups in this regard. Visual field was reduced by 15° in CLT group (P<0.001) and by 54.3° in CT group (P<0.001) compared to baseline, and VF differences between groups were also significant during telescope use. (P<0.001) Scores observed in both groups were similar in regard to VS. Telescope use difficulties were significant higher in CLT group (P=0.003) as well as CS scores (P<0.001) compared to CT group. Conclusions: Both telescopes provide similar improvement in VA in AMD patients with low-vision, but CLT caused less VF reduction than CT use. Patient satisfaction with the cosmetic appearance of the telescope was higher in CLT group, but UD was also higher in this group compared to CT group.
193

Rôle de l'apolipoprotéine E dans l'inflammation sous-rétinienne impliquée dans la Dégénérescence Maculaire Liée à l'Age / Role of apolipoprotein E in subretinal inflammation involved in Age-related Macular Degeneration

Levy, Olivier 23 January 2014 (has links)
La Dégénérescence Maculaire Liée à l'Age (DMLA) constitue dans les pays industrialisés la 1ère cause de cécité chez les personnes de plus de 50 ans, et représente un enjeu majeur de santé publique d'autant plus important que le vieillissement de la population ne fait que s'accroître. La forme atrophique de cette maladie, pour laquelle il n'existe actuellement aucun traitement, est notamment caractérisée par une inflammation sous-rétinienne associée une dégénérescence des photorécepteurs, et conduit à une perte progressive de la vision centrale pouvant aller jusqu'à la cécité. Nos résultats montrent qu'au stade précoce de la maladie (MLA) on peut déjà observer de nombreux phagocytes mononucléaires (PM) dans l'espace sous-rétinien, en contact avec les drusen. Ces PM expriment de l'apolipoprotéine E (APOE), protéine impliquée dans l'homéostasie lipidique et la régulation de réponses inflammatoires, qui est retrouvée dans les drusen des patients atteints de DMLA, et dont le variant génétique APOε2 est associé à un risque élevé de développer une DMLA. Grâce à l'utilisation de souris Cx3cr1GFP/GFP déficientes en CX3CR1, un récepteur de chimiokine, et de souris humanisées APOε2, les travaux présentés ici démontrent que l'APOE exerce un rôle pro-inflammatoire conduisant de manière dose-dépendante à une altération du privilège immun sous-rétinien. Cet environnement immunosuppresseur est dépendant du FasL exprimé par l'épithélium pigmentaire rétinien (EPR), et empêche en condition physiologique la présence de cellules inflammatoires dans la rétine externe. Nos résultats montrent que l’APOE stimule de manière autocrine la sécrétion d’IL-6 par les PM, possiblement par un mécanisme impliquant une activation des Toll-like receptors (TLR) et de leur corécepteur CD36. Nous montrons que l’IL-6 inhibe l’expression de FasL sur l’EPR et altère sa capacité de clairance sous-rétinienne, ce qui facilite la survie des PM infiltrants au contact des photorécepteurs. La persistance de cette inflammation pathologique dans la rétine externe conduit au cours du vieillissement à une dégénérescence des photorécepteurs, phénomène qui peut est inhibé chez des souris déficientes en APOE. Ensemble, ces résultats permettent d’apporter une explication inédite au risque élevé de développer une DMLA pour les porteurs de l’allèle APOε2, et pourrait ouvrir la voie vers de nouvelles perspectives thérapeutiques. / Age-related Macular Degeneration (AMD) is the first cause of blindness in people over 50 year old in industrialized countries, and represents a major public health concern as the population of elderly is more and more increasing. The atrophic form of the disease, for which there is currently no treatment available, is characterized by subretinal inflammation associated with photoreceptor degeneration and leads to a progressive loss of central vision that can lead to blindness. Our results show many mononuclear phagocytes (MP) are already present at the early stage of the disease (MLA), in the subretinal space and in apposition with drusen. These PM express apolipoprotein E (APOE), a protein involved in lipid homeostasis and the regulation of inflammatory responses, which is found in drusen in patients with AMD, and whose genetic APOε2 variant is associated with a high risk of developing AMD. Using Cx3cr1GFP/GFP mice (deficient in CX3CR1, a chemokine receptor) and humanized APOε2 mice, the work presented herein demonstrates that APOE exerts a pro-inflammatory role leading to a dose-dependent alteration of the subretinal immune privilege. This immunosuppressive environment is dependent upon FasL expression by the retinal pigment epithelium (RPE), and prevents in physiological condition the presence of inflammatory cells in the outer retina. Our results show that APOE stimulates in an autocrine fashion the secretion of IL -6 by PM, possibly through a mechanism involving activation of Toll- like receptors (TLR) and their coreceptor CD36. We show that IL-6 inhibits the expression of FasL on the RPE and impairs its subretinal clearance capacity, which facilitates the survival of infiltrating PM in contact with photoreceptors. The persistence of a pathological inflammation in the outer retina leads to age-dependent photoreceptor degeneration, which can be inhibited in APOE-deficient mice. Taken together, these results provide novel rationale for the higher risk of developing AMD for APOε2allele carriers, and could allow the emergence of new therapeutic perspectives.
194

Macular Pigment and Lens Optical Density Measurements-Evaluating a Flicker Machine with Novel Features

Mukherjee, Anirbaan 02 July 2015 (has links)
Age related macular degeneration (AMD) is one of the leading causes of blindness amongst the elderly. Macular pigment (MP) in the retina has been established to protect individuals against AMD. Improving levels of MP by diet or supplements is the constant quest of clinical practitioners and researchers, thus necessitating development of instruments capable of repeatable and reliable MP measurement. Cataract, a consequence of the rising opacity levels of the lens with age is one of the other major causes of blindness in the world. Mapcatsf, a LED-based microprocessor-controlled heterochromatic flicker photometer (HFP) using photopic vision is capable of measuring the levels of MP and the opacity of the lens in terms of optical density. Test-retest measurements conducted on 83 subjects were analyzed for repeatability in macular pigment optical density (MPOD) measurements. Reliability of the lens optical density (LOD) measurements were tested and compared with those obtained at absolute scotopic thresholds for 25 individuals. A supplement study with 32 individuals both in the young (50) age groups for 6 months further established Mapcatsf’s capacity to monitor changing levels of MP in individuals. As an overall outcome, high levels of repeatability and reliability were obtained in MPOD and LOD measurements establishing Mapcatsf as an instrument for use in clinical settings in the future.
195

The Relationship between Age-Related Macular Degeneration and Olfactory Function

Kar, Taner, Yildirim, Yildiray, Altundağ, Aytuğ, Sonmez, Murat, Kaya, Abdullah, Colakoglu, Kadir, Tekeli, Hakan, Cayonu, Melih, Hummel, Thomas 20 May 2020 (has links)
Background: Olfactory dysfunction is a common symptom of many neurodegenerative diseases, and age-related macular degeneration (AMD) is a late-onset neurodegenerative disease. Objective: Thus, the aim of this study was to investigate olfactory functions in patients with AMD. Methods: A total of 69 subjects with AMD and 69 age- and sex-matched healthy controls were enrolled. After a complete ophthalmic evaluation, the AMD patients were subclassified as earlyand late-stage AMD. Psychophysical testing of olfactory function was performed using the validated Sniffin’ Sticks test. Results: This study was carried out in 138 subjects, with a mean age of 74.3 ± 8.9 years (range 51–89). The current investigation showed the following two major findings: (1) patients with AMD had decreased olfactory abilities, especially in odor discrimination and odor identification, even at early stages compared to controls, whereas patients had decreased olfactory abilities in all subtasks of olfactory testings in advanced stages of AMD disease, and (2) as the visual acuity of AMD patients decreased, the olfactory abilities of these patients worsened. Conclusion: This study demonstrated that AMD had significant negative effects on all orthonasal olfactory tasks, particularly in advanced stages. Similar to other neurodegenerative diseases, odor discrimination and identification seemed to be more affected than odor detection threshold tasks.
196

Predictors of lost to follow up among patients with ischemic retinopathies: a retrospective cohort study

Swartz, Sinjin Charles 29 November 2020 (has links)
PURPOSE: Retinal and choroidal ischemic retinopathies such as retinal-vein occlusion (RVO), diabetic retinopathy (DR), and age-related macular degeneration (AMD) are ocular diseases caused by abnormal changes in the microvasculature. The ischemia can lead to macular edema or neovascularization, which can affect vision. Intravitreal injections (IVI) of anti-vascular endothelial growth factor (anti-VEGF) can help to reduce macular edema and improve visual acuity. Lost to follow-up (LTFU) after anti-VEGF injections increases the risk of vision loss in patients with RVO, DR, and AMD. METHODS: Patients scheduled for an IVI of anti-VEGF between September 2009 and September 2019 with either RVO, DR, or AMD were included in the analysis. LTFU was defined as missing an appointment without another evaluation for at least one interval exceeding 180 days. All patients were seen by a single provider at an urban, hospital-based, single-site retina practice in Boston, MA. RESULTS: Among the 698 patients (mean [SD] age, 70.23 [14.2] years; 373 [53.4%] female) identified as receiving an IVI, 121 (17.3%) were LTFU. Age was not found to be statistically different between the LTFU and not LTFU groups (mean difference, -1.67; 95% CI, -4.66¬–1.32; P=.27). Odds of LTFU was lower among patients with AMD (odds ratio [OR], 0.57; 95% CI, 0.36-0.92; P=.02). Odds of LTFU was greater among patients with Medicaid insurance (OR, 2.31; 95% CI, 1.22-4.33; P=.01), compared with patients with Medicare insurance. A trend towards higher risk of LTFU was seen in patients with DR (OR, 1.42; 95% CI, 0.94-2.15; P=.09) and a toward lower risk in patients with two or more eye diseases (OR, 0.53; 95% CI, 0.24-1.15; P=.10). Medicaid insurance was the only significant (P=.02) independent risk factor of LTFU in the multivariate regression. CONCLUSION: We found a high rate of LTFU after anti-VEGF injections among patients with RVO, DR, AMD, and identified risk and protective factors associated with LTFU among this population. Although our results may not be generalizable, data on LTFU in a clinical practice setting are needed to understand the scope of the problem so that interventions may be designed to improve outcomes.
197

Association of Vascular Versus Avascular Subretinal Hyperreflective Material With Aflibercept Response in Age-related Macular Degeneration / 加齢黄斑変性に伴うsubretinal hyperreflective materialの血流シグナルと抗VEGF治療反応性

Kawashima, Yu 23 March 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第22323号 / 医博第4564号 / 新制||医||1041(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 大森 孝一, 教授 横出 正之, 教授 山下 潤 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
198

Elucidating the Role of Photoreceptors in Age-Related Macular Degeneration and the Discovery of Potential Therapies

Cheng, Shun-Yun 30 September 2021 (has links)
Age-related macular degeneration (AMD) is the leading cause for visual impairment in the elderly. The etiology of AMD remains unclear. Clinical and histopathological studies suggest that photoreceptors play a role in disease progression. Here, we found that photoreceptors of AMD patients show adaptive changes in gene expression, suggestive of a nutrient shortage. To study the effect of these changes, we mimicked the metabolic alteration in mouse photoreceptors, by disruption of the Tuberous Sclerosis Complex (TSC). This led to AMD hallmarks, including the advanced stages of geographic atrophy (GA) and choroidal neovascularization (CNV). Furthermore, we found that disease onset requires the activity of the mammalian target of rapamycin complex 1 (mTORC1). To study the contribution of photoreceptors to disease, we profiled retinal phospholipids as photoreceptors are rich in phospholipids. We found a reduction in two docosahexaenoic acid (DHA)-containing phospholipids. Feeding DHA to mutant mice, alleviated most AMD-associated hallmarks. To study the inflammatory complications seen with current anti-vascular endothelial growth factor (VEGF) treatments for CNV we used rAAV-mediated gene transfer to overexpress an anti-VEGF protein. We found that inhibition of VEGF can promote retinal inflammation. The data suggests that targeting photoreceptor metabolism may provide novel therapies to treat AMD.
199

Long-term results regarding healing andcomplications after 25-gauge pars planavitrectomy for large full-thickness macularholes

Berggren, Amanda January 2021 (has links)
Introduction A full-thickness macular hole (FTMH) is a round deformity in the fovea that involve alllayers of the neurosensory retina. The condition is usually symptomatic and is associatedwith a decreased visual acuity (VA). Large FTMHs are associated to a larger decrease in VA.To treat FTMH pars plana vitrectomy (PPV) is performed to repair the hole. There aredifferent dimensions of instruments in PPV but limited information on the outcome usingeach dimension. Aim This study aims to assess the healing rate of large FTMHs after 25-gauge vitrectomy. Methods The study is a retrospective record review. Patients were identified through the surgicalintervention registry at the Department of Ophthalmology, USÖ. The study included largeFTMHs (diameter &gt; 400 μm) who underwent 25-gauge PPV at USÖ between 2015-2017. Results After 25-gauge PPV 19 (82.6%) out of 23 included eyes healed. No significant difference inhealing rate between subgroups of different sized FTMHs was discovered. Out of 4 eyes thatfailed to heal, 1 patient underwent a reoperation and the other 3 either chose not to or it wasdeemed not indicated. A statistically significant increase in mean VA postoperatively wasobserved. The most reported complications postoperatively were gas cataract and atemporary increase in intraocular pressure. In 7 cases the PPV led to an accelerateddevelopment of cataract and cataract surgery. Conclusion The majority of FTMHs healed after 25-gauge PPV and the mean VA increased after surgery.The most common complications were secondary cataract and temporary increase in IOP.
200

Osmotische Induktion des Komplementfaktors C9 in retinalen Pigmentepithelzellen

Ackmann, Charlotte 16 March 2017 (has links)
Ackmann, Charlotte Osmotische Induktion des Komplementfaktors C9 in retinalen Pigmentepithelzellen Universität Leipzig, Dissertation 98 Seiten, 208 Literaturangaben, 28 Abbildungen, 8 Tabellen Die altersbedingte Makuladegeneration (AMD) ist die häufigste Ursache für Erblindung bei Erwachsenen in den industrialisierten Ländern. Die AMD ist unter anderem eine chronisch entzündliche Erkrankung, bei der die Aktivierung der alternativen Komplementkaskade eine Rolle spielt. Daneben erhöht Bluthochdruck, der auch durch eine salzreiche Ernährung getriggert wird, das Risiko an einer AMD zu erkranken. Untersucht wurde die Genexpression des Komplementfaktors C9 unter verschiedenen pathologischen Bedingungen in humanen retinalen Pigmentepithel (RPE)-Zellen sowie deren Wirkung auf die physiologischen Eigenschaften der Zellen. Gezeigt wird, dass die Expression des C9 Gens in humanen RPE-Zellen spezifisch durch Hyperosmolarität, Hypoxie und oxidativen Stress induziert wird. Die Menge an C9 Protein wurde durch Hyperosmolarität leicht aber signifikant erhöht. Die hyperosmotische Induktion der C9 mRNA ist abhängig von der Aktivierung der Signalproteine p38 MAPK, ERK1/2, JNK, PI3K, sowie der Transkriptionsfaktoren STAT3 und NFAT5 während für die Hypoxie-induzierte C9 mRNA Expression nur eine Beteiligung des Transkriptionsfaktors STAT3 nachgewiesen wurde. Die Aktivierung verschiedener Signalwege durch Hyper-osmolarität und Hypoxie lässt vermuten, dass eine hohe Kochsalzaufnahme auch unter normoxischen Verhältnissen die Eigenschaften RPE-Zellen verändert. Hyperosmolarität hemmt die Proliferation und Migration der RPE-Zellen, während chemische Hypoxie nur die Proliferationsrate verringert. Die Wirkung einer erhöhten extrazellulären NaCl-Konzentration auf die C9 mRNA Expression wird über zwei Mechanismen vermittelt: über die Erhöhung der extrazellulären Osmolarität und über die Veränderung des NaCl-Gradienten über der Plasmamembran. Die NaCl Wirkung über den veränderten NaCl-Gradienten lässt vermuten, dass eine übermäßige Aufnahme von Kochsalz nicht nur über die Erhöhung des Blutdruckes die Pathogenese der AMD stimuliert, sondern dass Kochsalz auch eine direkte stimulierende Wirkung auf RPE-Zellen besitzt. Diese Vermutung könnte erklären, weshalb hoher Blutdruck ein Risikofaktor der AMD ist, aber Medikamente zur Behandlung des Bluthochdruckes das Risiko der AMD nicht verändert.:Inhaltsverzeichnis Bibliographische Beschreibung IV Abkürzungsverzeichnis V 1. EINLEITUNG 1 1.1. Das retinale Pigmentepithel (RPE) 1 1.2. Die altersbedingte Makuladegeneration (AMD) 2 1.2.1. Die atrophe AMD 3 1.2.2. Die exsudative AMD 4 1.2.3. Die Aktivierung des Komplementsystems bei der exsudativen AMD 5 1.3. Risikofaktoren der AMD 7 1.4. Einfluss von Hypertonie auf die AMD 9 1.4.1. Hypertonie 9 1.4.2. Hypertonie als Risikofaktor der AMD 10 1.5. Therapie der AMD 11 2. FRAGESTELLUNG 13 3. MATERIAL UND METHODEN 14 3.1. Arbeitsmaterialien 14 3.1.1. Substanzen 14 3.1.2. Medien 15 3.1.3. Kits 15 3.1.4. Primer 16 3.1.5. Längenstandards 16 3.1.6. Antikörper 16 3.1.7. Rekombinante humane Proteine 17 3.1.8. Selektive Hemmer 17 3.1.9. Geräte 17 3.2. Zellbiologische Methoden 19 3.2.1. Zellkultivierung 19 3.2.2. Zellstimulation 20 3.2.3. Bestimmung der Proliferationsrate 21 3.2.4. Zellmigration 22 3.3. Molekularbiologische Methoden 23 3.3.1. RNA-Präparation 23 3.3.2. RNA Quantifizierung 24 3.3.3. cDNA-Synthese 24 3.3.4. Real-Time PCR 24 3.3.5. Agarose-Gel-Elektrophorese 26 3.3.6. Untersuchungen mit short interfering (si) RNA 27 3.4. Immunologische Methoden 28 3.4.1. Western Blot 28 3.4.1.1. Extraktherstellung aus RPE-Zellen 28 3.4.1.2. Proteinkonzentrationsbestimmung nach Bradford 29 3.4.1.3. SDS-Gelektrophorese 30 3.4.1.4. Western Blot 32 3.5. Statistische Auswertung 33 4. ERGEBNISSE 34 4.1. Regulation der Genexpression von Komplementfaktoren in RPE-Zellen 34 4.1.1. Hyperosmolarität erzeugt durch NaCl 34 4.1.2. Hyperosmolarität erzeugt durch Sucrose 36 4.1.3. Wirkung von Hypoosmolarität und oxidativem Stress 37 4.1.4. Wirkung von Hypoxie 38 4.1.5. Gemeinsame Wirkung von CoCl2 und NaCl 38 4.1.6. Wirkung von Zytokinen 39 4.1.7. Wirkung von Serum- und Gerinnungsfaktoren sowie Glukose 40 4.1.8. Wirkung von Entzündungsmediatoren 40 4.1.9. Wirkung von Matrixmetalloproteinase und Triamcinolon 41 4.2. Wirkung von Hyperosmolarität auf die Transkription und die Stabilität der C9 mRNA 42 4.3. Beteiligung intrazellulärer Signalwege und Transkriptionsfaktoren an der Induktion der C9 mRNA unter Hyperosmolarität und Hypoxie in RPE-Zellen 43 4.3.1. Beteiligung intrazellulärer Signalwege und Transkriptionsfaktoren an der NaCl-induzierten C9 mRNA Expression in RPE-Zellen 43 4.3.2. Hyperosmolare Induktion der C9 mRNA: Einfluss des Transkriptionsfaktors NFAT5 44 4.3.3. Beteiligung intrazellulärer Signalwege und Transkriptionsfaktoren an der Hypoxie-induzierten C9 mRNA Expression bei RPE-Zellen 46 4.4. Aktivierung intrazellulärer Signalproteine durch Hyperosmolarität bzw. Hypoxie 47 4.5. Wirkung von Hyperosmolarität auf das C9 Protein 48 4.6. Wirkung von Hyperosmolarität auf die physiologischen Eigenschaften der RPE- Zellen 50 4.6.1. Wirkung von Hyperosmolarität auf die Zellproliferation 50 4.6.2. Wirkung von Hyperosmolarität auf die Zellmigration 51 4.6.3. Wirkung von Hyperosmolarität auf die Zellvitalität 51 5. DISSKUSION 53 5.1. Wirkung von Hyper-, Hypoosmolarqität, Hypoxie und oxidativem Stress auf die Genexpression von C9 in humanen RPE-Zellen 53 5.3. Wirkung von Hyperosmolarität auf die Stabilität der C9 mRNA 56 5.4. Beteiligung intrazellulärer Signalwege und Transkriptionsfaktoren an der NaCl- bzw. CoCl2-induzierten C9 mRNA Expression in RPE-Zellen 56 5.5. Einfluss des Transkriptionsfaktors NFAT5 auf die hyperosmolare C9 Induktion 58 5.6. Aktivierung intrazellulärer Signalproteine durch Hyperosmolarität bzw. Hypoxie 58 5.7. Wirkung von Hyperosmolarität auf das C9 Protein 59 5.8. Wirkung des Komplementfaktors C9 und der Hyperosmolarität auf die physiologischen Eigenschaften von RPE-Zellen 60 5.8.1. Wirkung auf die Zellproliferation 60 5.8.2. Wirkung auf die Zellmigration 60 5.8.3. Wirkung auf die Zellvitalität 61 5.9. Bedeutung für das Verständnis der Pathogenese der AMD 61 6. ZUSAMMENFASSUNG 63 7. LITERATURVERSZEICHNIS 68 8. TABELLENVERZEICHNIS 85 9. ABBILDUNGSVERZEICHNIS 86 10. ANHANG 88 10.1. Eigenständigkeitserklärung 88 10.2. Lebenslauf 89 10.3. Danksagung 90

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