Spelling suggestions: "subject:"choroidal revascularization"" "subject:"choroidal vascularization""
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Posouzení účinnosti fotodynamické terapie u pacientů s chronickou centrální serózní chorioretionopatií / Assessment of the Efficacy of Photodynamic Therapy in Patients with Chronic Central Serous ChorioretinopathyMyslík Manethová, Kateřina January 2021 (has links)
Assessment of the efficacy of photodynamic therapy in patients with chronic central serous chorioretinopathy The presented postgraduate thesis deals with the issue of macular edema based on central serous chorioretinopathy (CSC) and the current possibilities of therapeutic solution of this disease. Although in most cases central serous chorioretinopathy does not belong to frequent and vision-threatening diseases, it can, especially its chronic form, lead to impaired vision. The aim of the theoretical part of this work is to characterize this chorioretinal disease and describe the basic principles of treatment. The work also describes the pathogenesis of CSC, the examination methods, the up-to-date accepted CSC classification and the therapeutic modalities of the treatment of the disease. The clinical part of this work is a prospective study of 52 patients (54 eyes), aged 30- 75, with chronic form of central serous chorioretinopathy treated at the Eye Clinic of the 1st Faculty of Medicine of Charles University and Military University Hospital Prague in the years 2012 to 2018. The aim of this prospective study is to evaluate the anatomical and functional results of the treatment of 54 eyes with chronic form of central serous chorioretinopathy using photodynamic therapy in a reduced (half) dosing...
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CLINICAL AND GENETIC CHARACTERISTICS OF JAPANESE PATIENTS WITH AGE-RELATED MACULAR DEGENERATION AND PSEUDODRUSEN / 日本人における加齢黄斑変性とシュードドルーゼンの臨床的および遺伝学的特徴Sufian, Elfandi 26 March 2018 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第21002号 / 医博第4348号 / 新制||医||1027(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 山田 亮, 教授 Shohab YOUSSEFIAN / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
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Les effets anti-angiogéniques des microparticules dérivées des lymphocytes T sur la néovascularisation choroïdienneTahiri, Houda 08 1900 (has links)
No description available.
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Immunosenescence in Choroidal Neovascularization (CNV): Transcriptional Profiling of Naïve and CNV-Associated Retinal Myeloid Cells during AgingSchlecht, Anja, Thien, Adrian, Wolf, Julian, Prinz, Gabriele, Agostini, Hansjürgen, Schlunck, Günther, Wieghofer, Peter, Boneva, Stefaniya, Lange, Clemens 02 February 2024 (has links)
Immunosenescence is considered a possible factor in the development of age-related macular
degeneration and choroidal neovascularization (CNV). However, age-related changes of myeloid
cells (MCs), such as microglia and macrophages, in the healthy retina or during CNV formation are illdefined.
In this study, Cx3cr1-positive MCs were isolated by fluorescence-activated cell sorting from
six-week (young) and two-year-old (old) Cx3cr1GFP/+ mice, both during physiological aging and
laser-induced CNV development. High-throughput RNA-sequencing was performed to define the
age-dependent transcriptional differences in MCs during physiological aging and CNV development,
complemented by immunohistochemical characterization and the quantification of MCs, as well as
CNV size measurements. These analyses revealed that myeloid cells change their transcriptional
profile during both aging and CNV development. In the steady state, senescent MCs demonstrated
an upregulation of factors contributing to cell proliferation and chemotaxis, such as Cxcl13 and Cxcl14,
as well as the downregulation of microglial signature genes. During CNV formation, aged myeloid
cells revealed a significant upregulation of angiogenic factors such as Arg1 and Lrg1 concomitant
with significantly enlarged CNV and an increased accumulation of MCs in aged mice in comparison
to young mice. Future studies need to clarify whether this observation is an epiphenomenon or a
causal relationship to determine the role of immunosenescence in CNV formation.
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Mechanistic and therapeutic evaluation of a novel antiantiogenic small moleculeSulaiman, Rania S. 24 May 2016 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Choroidal neovascularization (CNV) is the vision-threatening characteristic of wet
age-related macular degeneration (AMD), a major cause of blindness affecting
almost 2 million elderly Americans. The current approved treatments target the
dominant angiogenic mediator, vascular endothelial growth factor (VEGF).
However, repeated injections of anti-VEGF drugs can cause ocular and systemic
side effects, and about 30% of wet AMD patients are non-responsive. There is
thus an unmet need to develop VEGF-independent antiangiogenic molecules to
complement or combine with existing medications.
I studied SH-11037, a novel homoisoflavonoid with potent and selective
antiangiogenic activity against human retinal endothelial cells. Intravitreal SH-
11037 dose-dependently suppressed angiogenesis in the laser-induced CNV (LCNV)
mouse model. These effects were prominent as early as 7 days post-laser
treatment as measured by a novel ellipsoid quantification method of optical
coherence tomography images in vivo. A supratherapeutic dose of 100 μM SH-
11037 was not associated with signs of murine ocular toxicity, and did not
interfere with pre-existing retinal vasculature or retinal function. SH-11037
synergized with anti-VEGF therapy in vitro and in vivo, suggesting a VEGFindependent
mechanism. By photoaffinity pulldown, I identified soluble epoxide hydrolase (sEH) as an SH-11037-binding target. sEH is a key enzyme in ω-3 and
ω-6 fatty acid metabolism. sEH levels were dramatically upregulated in retinal
sections from L-CNV mice and a specific sEH inhibitor, t-AUCB, significantly
suppressed L-CNV lesion volume. Additionally, SH-11037 inhibited sEH
enzymatic activity in vitro and in vivo in L-CNV mice. Given the role of sEH in the
metabolism of docosahexaenoic acids (DHA), inhibition of sEH using small
molecules like SH-11037 would enhance ocular DHA levels, with beneficial
antiangiogenic and anti-inflammatory effects. SH-11037 is thus a novel sEH
inhibitor, which could make it an alternative or additive therapy to existing anti-
VEGF drugs for treatment of neovascular diseases in the eye and other tissues.
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Caractérisation du jeûne intermittent dans un modèle de néovascularisation choroïdienne chez la sourisFaquette, Marie-Lou 11 1900 (has links)
La dégénérescence maculaire liée à l’âge (DMLA) est une des premières causes de cécité pour les personnes âgées de plus de 50 ans. Elle existe sous deux formes : sèche et humide. La forme causant les pertes de vision les plus sévères et rapides est DMLA humide où des nouveaux vaisseaux sanguins anormaux se forment dans la rétine; ce processus est appelé la néovascularisation choroïdienne. Celui-ci est causé par la dégradation des différentes membranes de la rétine et de l’augmentation du VEGF stimulant la croissance de ces vaisseaux. L’obésité, l’hypertension, le diabète et la cigarette sont connus pour être des facteurs modifiables et fortement corrélés avec la maladie. Avec l’arrivée des nombreuses diètes tendances, le jeûne intermittent pourrait être une intervention non-pharmacologique impactant l’obésité, l’hypertension et le diabète. En effet, cette diète est reconnue pour améliorer la santé, améliore la sensibilité à l’insuline et la tolérance glucose, diminuer le cholestérol sanguin et exercerait un effet bénéfique sur l’obésité.
Ce mémoire a été entrepris dans le but d’évaluer les avantages potentiels du cycle de diète, soit le jeûne intermittent, sur la néovascularisation choroïdienne dans un modèle de DMLA. Nous avons émis l’hypothèse que le jeûne intermittent permet la diminution de la néovascularisation choroïdienne. Nos résultats montrent que les souris sous le régime jeûne intermittent que nous avons utilisé, c’est-à-dire 2 jours d’alimentation pour 1 jour de jeûne, ne perdent pas de poids, et suivent le même schéma de prise de poids que les souris nourries à volonté. De plus, les souris sous jeûne intermittent n’ont pas d’avantage métabolique que ce soit au niveau du glucose et, encore, moins au niveau de l’insuline. Les résultats ne permettent pas de montrer une différence au niveau de la néovascularisation choroïdienne induit par notre modèle. Le modèle de jeûne intermittent choisit ne permet pas d’obtenir des avantages au niveau de la néovascularisation choroïdienne ni pour la sensibilité au glucose et à l’insuline / Age-related macular degeneration (AMD) is one of the most prominent causes of blindness for people over 50 years old. It exists in two forms: dry and wet. The form causing majority of loss of sight is caused by wet AMD from where new abnormal blood vessels form in retina. This process is called choroidal neovascularization. This is caused by degeneration of outer portion of the retina and an increase in VEGF that instigate the growth of the new blood vessels. Obesity, hypertension, diabetes and smoking are known to be modifiable factors and strongly correlated with the disease. The advent of a vast number of trendy diets has introduced the possibility of modulating chronic disease by modifying eating habits. As an example, intermittent fasting can impacting obesity, hypertension, and diabetes. Indeed, this diet has been known to improve health, increase sensitivity of insulin and glucose, lower cholesterol and to have beneficial effect in obesity.
The purpose of the research in my master’s thesis is to evaluate the influence of diet cycle, intermittent fasting on choroidal neovascularization in a mouse model of AMD. We hypothesized that the intermittent fasting could be diminish the choroidal neovascularization. There are several experimental paradigms that reproduce intermittent fasting. We selected the intermittent fasting 2 days of eating for one day of fasting (IF 2:1). Our results show that mice on our selected intermittent fasting regimen did not lose weight and follow the same pattern of weight gain as the mice that fed ad libitum. Furthermore, the mice on this intermittent fasting diet paradigm didn’t have metabolic benefits on glucose or insulin tolerance. Our results also did not show any differences in choroidal neovascularization. Hence, the 2:1 paradigm of intermittent fasting didn’t show any benefits on choroidal neovascularization, nor glucose and insulin.
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Machine learning assisted decision support system for image analysis of OCTYacoub, Elias January 2022 (has links)
Optical Coherence Tomography (OCT) has been around for more than 30 years and is still being continuously improved. The department of ophthalmology is a part of Sahlgrenska Hospital that heavily uses OCT for helping people with the treatment of eye diseases. They are currently facing a problem where the time to go from an OCT scan to treatment is being increased due to having an overload of patient visits every day. Since it requires a trained expert to analyze each OCT scan, the increase of patients is too overwhelming for the few experts that the department has. It is believed that the next phase of this medical field will be through the adoption of machine learning technology. This thesis has been issued by Sahlgrenska University Hospital (SUH), and they want to address the problem that ophthalmology has by introducing the use of machine learning into their workflow. This thesis aims to determine the best suited CNN through training and testing of pre-trained models and to build a tool that a model can be integrated into for use in ophthalmology. Transfer learning was used to compare three different types of pre-trained models offered by Keras, namely VGG16, InceptionResNet50V2 and ResNet50V2. They were all trained on an open dataset containing 84495 OCT images categorized into four different classes. These include the three diseases Choroidal Neovascularization (CNV), Diabetic Macular Edema (DME), drusen and normal eyes. To further improve the accuracy of the models, oversampling, undersampling, and data augmentation were applied to the training set and then tested in different variations. A web application was built using Tensorflow.js and Node.js that the best-performed model later was integrated into. The VGG16 model performed the best with only oversampling applied out of the three. It yielded an average of 95% precision, 95% recall and got a 95% F1-score. The second was the Inception model with only oversampling applied that got an average of 93% precision, 93% recall and a 93% F1-score. Last came the ResNet model with an average of 93% precision, 92% recall and a 92% F1-score. The results suggest that oversampling is the overall best technique for this given dataset. The chosen data augmentation techniques only lead to models performing marginally worse in all cases. It also suggests that pre-trained models with more parameters, such as the VGG16 model, have more feature mappings and, therefore, achieve higher accuracy. On this basis, parameters and better mappings of features should be taken into account when using pre-trained models.
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Regulation of inflammation in choroidal neovascularization in age related macular degenerationAndriessen, Elisabeth MMA 10 1900 (has links)
La dégénérescence maculaire liée à l'âge (DMLA) est la cause la plus fréquente de déficience visuelle
centrale irréversible chez les personnes de plus de 50 ans dans les pays industrialisés, avec des
impacts sociétaux et financiers majeurs. La DMLA est une maladie à multiples facettes provoquée par
des interactions entre les facteurs de risque et les antécédents génétiques et l'inflammation joue un
rôle important. Les effets pro-inflammatoires provoquent une perturbation de l'environnement sousrétinien
physiologiquement immunosuppresseur. L'accumulation de phagocytes mononucléaires
(PM) dans l'espace sous-rétinien qui s'ensuit est au coeur de l'étiologie des formes atrophiques et
humides de la DMLA.
Après l’usage de tabac, l'obésité est l'un des facteurs de risque modifiables les plus importants. Nous
avons démontré que les régimes riches en graisses exacerbent la néovascularisation choroïdienne
(NVC) en modifiant le microbiote intestinal. La dysbiose intestinale entraîne une perméabilité
intestinale accrue, une inflammation chronique de bas grade, une augmentation des PM sur le site
de l'angiogenèse pathologique dans l'oeil et exacerbe finalement la NVC. La modification du
microbiote peut réduire l'inflammation et atténuer la NVC et peut ainsi fournir des traitements peu
intrusifs et rentables pour prévenir ou retarder la DMLA exsudative.
Une autre option thérapeutique qui pourrait réduire la NVC par modulation inflammatoire consiste
à piéger localement les ligands de NRP1 avec un piège dérivé de NRP1. Les ligands de NRP1 sont
élevés dans le vitré des patients atteints de DMLA. Nous avons constaté que les PM exprimant NRP1
favorisaient la NVC en atténuant la production de facteurs inflammatoires et en favorisant l'activation
alternative, donnant aux PM un caractère pro-angiogénique. Les PM moins inflammatoires et plus de
type M2 qui sont enrichis avec l'âge et exacerbent la NVC peuvent être modulés et devenir moins
nuisibles en empêchant l'activation de NRP1.
Cette thèse explore deux angles dans lesquels la régulation de l'inflammation peut influencer la
formation de NVC et jette les bases du développement futur de nouveaux traitements préventifs
primaires et secondaires efficaces dans le contexte de la DMLA. / Age related macular degeneration (AMD) is the most common cause of irreversible central vision
impairment in people over 50 in industrialized countries, with major societal and financial
impacts. AMD is a multifaceted disease provoked by interactions among environmental risk
factors and genetic backgrounds in which inflammation plays an important role. Proinflammatory
effects cause a disruption of the physiologically immunosuppressive subretinal environment. The
ensuing accumulation of mononuclear phagocytes in the subretinal space is central to the
etiology of both atrophic and wet forms of AMD.
After smoking, obesity is one of the most important modifiable risk factors. We demonstrate that
high-fat diets exacerbate choroidal neovascularisation (CNV) by altering gut microbiota. Gut
dysbiosis leads to heightened intestinal permeability and chronic low-grade inflammation,
increases recruitment of microglia and macrophages to the site of pathological angiogenesis in
the eye and ultimately exacerbates CNV. Modifying microbiota can reduce systemic and local
choroidal inflammation and attenuate pathological neovascularization and may thus provide
minimally intrusive and cost-effective paradigms to prevent or delay exudative AMD.
Another therapeutic option that could reduce CNV through inflammatory modulation is locally
trapping ligands of NRP1 with a NRP1-derived trap. Ligands for NRP1 are elevated in the vitreous
of patients with AMD at times of active CNV. We found that NRP1-expressing MPs promote CNV
by mitigating production of inflammatory factors and promoting alternative activation, giving the
MPs a pro-angiogenic character. The less inflammatory and more M2-like MPs that are enriched
with age and exacerbate CNV can be rendered less detrimental by hindering NRP1 activation.
This thesis explores two angles wherein regulation of inflammation can influence the formation
of CNV and lays the groundwork for future development of novel effective primary and secondary
preventive treatments for AMD.
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Exploring the link between adipose tissue, obesity and age-related macular degenerationDiaz Marin, Roberto 08 1900 (has links)
L’obésité est en croissance rapide à l’échelle mondiale et représente un facteur de risque important pour plusieurs pathologies, dont la dégénérescence maculaire liée à l’âge (DMLA). Dans l’obésité, le tissu adipeux blanc (WAT) subi un remodelage pathologique caractérisé par le recrutement de macrophages pro-inflammatoires facilitant l’établissement de l’inflammation stérile systémique. Contrairement au WAT, les tissus adipeux brun (BAT) et beige (BgAT) participent à la thermogénèse, un processus qui libère de la chaleur en métabolisant les lipides. En raison de leurs potentiels effets physiologiques bénéfiques, le recrutement d’adipocytes et l’activation de ces types spécifiques de tissu adipeux (AT) ont fait l’objet de multiples recherches et débats. Malgré les avancées considérables dans le domaine, les mécanismes impliqués dans l’activation du BAT et du BgAT ainsi que les mécanismes impliqués dans le développement de l’obésité et leur contribution à des maladies comme la DMLA, restent mal définis.
Dans un premier temps, nous avons développé le protocole RELi pour permettre une extraction et une quantification fiable des protéines du AT murin saturé en lipides. Notre protocole élimine les lipides contaminants en excès, réduit la variabilité du chargement de protéines pour le western blot et l’usage de gènes de ménage standards (Article #1). Ensuite, nous avons étudié l’inflammation au niveau du BAT dans un modèle d’obésité induite par l’alimentation. La délétion de la Neuropiline 1 (NRP1) chez les macrophages résidents du tissu adipeux (ATMs) a provoqué une diminution des densités de la vasculature et de l’innervation. De plus ces souris sont devenues plus sensibles à l’exposition au froid suggérant un rôle des ATMs-Nrp1+ dans la régulation de l’homéostasie du BAT et de la température corporelle (Article #2). Finalement, nous avons exploré l’axe BgAT-DMLA; plus spécifiquement son impact potentiel sur la néovascularization choroïdienne (CNV) en utilisant des approches in vivo et in vitro. Nous avons démontré que la délétion génétique de PRD1-BF1-RIZ1 homologous domain containing 16 (PRDM16), un gène impliqué dans la thermogénèse, conduit à une réduction de la CNV, et que la réintroduction d’AT-PRDM16+ exacerbe la formation de CNV pathologique. Le traitement d’explants de choroïde avec du milieu conditionné par des adipocytes-PRDM16+ augmente la croissance des vaisseaux sanguins. Ensemble, les données suggèrent un rôle sécrétoire potentiel pour le BgAT-PRDM16+ capable d’influencer la formation distale de CNV qui pourrait être pertinente pour la DMLA (Article #3).
Les travaux présentés dans cette thèse établissent les bases d’un protocole permettant l’obtention de résultats reproductibles dans l’étude du AT, soulignent l’importance des ATMs- Nrp1+ dans la régulation de l’homéostasie du BAT et explorent pour la première fois l’implication du BgAT-PRDM16+ chez la DMLA neovasculaire. Ce travail établit les bases de la compréhension des mécanismes moléculaires reliant la régulation du AT thermogénique et les pathologies caractérisées par un excès de gras. Ce travail souligne également l’importance d’évaluer l’activation du BgAT chez les patients atteints de la DMLA. / Obesity is rapidly growing worldwide and represents a significant risk factor to several pathologies, including age-related macular degeneration (AMD). In obesity, the white adipose tissue (WAT) undergoes a strong remodeling characterized by the recruitment of pro- inflammatory macrophages, facilitating low-grade chronic inflammation. Unlike WAT, brown (BAT) and beige (BgAT) adipose tissues participate in thermogenesis, a process that releases heat by metabolizing lipids. Due to the likely beneficial physiological effects of BAT and BgAT, the recruitment of adipocytes and activation of these specific types of adipose tissue (AT) has been the subject of much research and debate. Despite considerable advances in the field, the mechanisms involved in BAT- and BgAT-activation as well as mechanisms involved in the development of obesity and their contribution to diseases such as AMD, remain ill-defined.
First, we developed the RELi protocol to allow a reliable extraction and quantification of proteins from murine AT saturated with lipids. Our protocol eliminates excess contaminating lipids, reduces the variability of protein loading in Western blot and stabilizes expression of housekeeping genes (Article #1). Next, we investigated the inflammatory component of BAT in a diet-induced obesity model. The deletion of NRP1 in resident adipose tissue macrophages (ATMs) led to the expansion of the BAT and affected the densities of the vasculature and the innervation. Moreover, these mice became more sensitive to cold exposure, suggesting a role of ATMs-Nrp1+ in the regulation of BAT homeostasis and body temperature (Article #2). Lastly, we explored the axis of BgAT and AMD; more specifically, its potential impact on choroidal neovascularization (CNV) using in vivo and in vitro approaches. We demonstrated that the genetic deletion in BgAT of PRD1-BF1-RIZ1 homologous domain containing 16 (PRDM16), a gene involved in thermogenesis, leads to a reduction of CNV, and that the reintroduction of BgAT-PRDM16+ via AT transplantation exacerbates the formation of pathological CNV. Treatment of choroid explants with PRDM16+-adipocyte-conditioned medium augmented blood vessel growth. Altogether, the data suggest a potential secretory role for BgAT-PRDM16+ to influence distal CNV formation that could be relevant to AMD (Article #3).
The work presented in this thesis establishes the basis of a protocol allowing reproducible results in the study of AT, underlines the importance of ATMs-Nrp1+ in the regulation of BAT homeostasis and explores, for the first time, the involvement of BgAT-PRDM16+ in neovascular AMD. This work sets the basis for the understanding of the molecular mechanisms linking the regulation of thermogenic AT and pathologies characterized by an excess of fat. This work also highlights the importance of assessing the activation of BgAT in patients with AMD.
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The Effects of Lactate Receptor G Protein-Coupled Receptor 81 (GPR81) on the Integrity of the Choroidal VasculatureYang, Xiaojuan 02 1900 (has links)
No description available.
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