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1

Mohammed, Hesham Hamada Taha. "Molecular analysis of adenylyl cyclase : bacillus anthracis edema factor exotoxin." kostenfrei, 2009. http://www.opus-bayern.de/uni-regensburg/volltexte/2010/1411/.

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2

Bhandari, Sanjeeb. "Real-world Treatment Outcomes for Diabetic Macular Edema." Thesis, University of Sydney, 2020. https://hdl.handle.net/2123/24071.

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Background Diabetic macular edema (DME) impairs vision and reduces the quality of life. Clinical trials of intravitreal vascular endothelial growth factor (VEGF) inhibitors and steroids for DME have reported remarkable improvements in visual acuity (VA) that had not been previously achieved with laser treatment. Aims This research was divided into three components with a common theme of evaluating real-world treatment outcomes of DME. The first component aimed to study the changes in the treatment patterns for DME in routine clinical practice from 2009 – 2019 and 5-year outcomes. The second component aimed to assess the outcomes of cataract surgery in eyes receiving intravitreal treatments for DME in routine clinical practice. The third aimed to compare the 12-month treatment outcomes of aflibercept with ranibizumab in eyes with DME. Methods These were retrospective analyses of data from a prospectively designed web-based outcomes registry – the Fight Retinal Blindness! Registry. The registry has implemented the DME module to collect data on eyes receiving intravitreal treatment for DME in routine clinical practice. Results Treatment choice changed to predominantly VEGF inhibitors from 2011 onwards. The choice of VEGF inhibitor changed from mainly off-label (bevacizumab) to mainly on-label (ranibizumab or aflibercept). The mean VA at baseline improved from 2009 to 2014 (58 and 68 letters) as did the mean VA change at 5 years (+4.5 and +5.3 letters). Eyes received fewer treatments than those in clinical trials throughout the period studied. The mean VA 6 months after cataract surgery improved and was similar to their matched phakic controls. The mean central subfield thickness (CST) both 6 months before (341μm) and after (360μm) surgery were similar (p=0.08). However, eyes which underwent cataract surgery had thicker maculae and received more injections than their matched controls both before and after surgery. Eyes receiving aflibercept or ranibizumab had improved vision and reduced macular thickness at 12 months when the 2 drugs were compared head to head for DME. Eyes receiving aflibercept had greater reduction in CST than those receiving ranibizumab. Among eyes with initial VA ≤ 20/50, larger VA gains were observed in eyes treated with aflibercept. Conclusions VEGF inhibitors became the preferred treatment for DME in real-world setting during the period studied, although they were given less often than in the pivotal clinical trials. Visual outcomes of cataract surgery in eyes with DME treatment were acceptable. Aflibercept outcomes were somewhat better than ranibizumab over the first 12 months of DME treatment. These findings may be a useful guide to clinicians as to the optimal management of eyes with DME.
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3

Gómez, Sánchez Sandra. "Influencia de la interfase vitreorretiniana en la evolución del edema macular diabético después del tratamiento con inyecciones intravítreas de inhibidores del factor de crecimiento endotelial vascular." Doctoral thesis, Universitat Autònoma de Barcelona, 2017. http://hdl.handle.net/10803/456317.

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JUSTIFICACIÓN: Uno de los tratamientos de primera línea del edema macular diabético (EMD) son las inyecciones intravítreas de fármacos inhibidores del factor de crecimiento endotelial vascular (antiVEGF). El alto impacto clínico, social y económico de esta patología ha hecho aumentar el interés en la detección de biomarcadores pronósticos de respuesta al tratamiento con el fin de mejorar la individualización del tratamiento disminuyendo la sobrecarga asistencial en los departamentos de oftalmología. El desprendimiento de vítreo (DVP) en pacientes diagnosticados de EMD es un acontecimiento poco estudiado, sin embargo, los estudios publicados coinciden en una menor tasa de DVP en pacientes con EMD que en pacientes sin EMD. OBJETIVOS: Demostrar que las inyecciones intravítreas de antiVEGF en pacientes con EMD inducen el DVP, demostrar que la presencia de DVP en pacientes con EMD mejora la eficacia del tratamiento con inyecciones de antivEGF, y demostrar que la presencia de DVP disminuye el número de inyecciones de antiVEGF necesarias para el tratamiento del EMD. MATERIAL Y MÉTODOS: Se ha realizado un estudio observacional, prospectivo y longitudinal, comparando dos grupos en función de la presencia (Grupo 1: 18 ojos) o ausencia (Grupo 2: 20 ojos) de adherencia vitreomacular (AVM) a los 12 meses de seguimiento. El protocolo de estudio consistía en visitas cada 2 meses durante 1 año, evaluando en todas las visitas la agudeza visual (AV), el grosor foveal (CFT) y el grado de DVP. El régimen de tratamiento consistió en una pauta fija de 3 inyecciones intravítreas de Ranibizumab cada 2 meses y después una pauta pro re nata bimestral. Se incluyó también un grupo control de 10 ojos de pacientes diabéticos sin EMD para analizar la incidencia de DVP al año de seguimiento. RESULTADOS: Al inicio, un 76.32% de los pacientes presentaban AVM, y al año se observó una tasa de acontecimiento del DVP del 37.9% en pacientes que habían recibido tratamiento con inyecciones intravítreas de antiVEGF mientras que no se observó ningún caso en el grupo control (p<0.001). La mejoría de AV fue de 6.94 letras en el Grupo 1 (p=0.03) y de 4.9 letras en el Grupo 2 (p=0.08), siendo esta diferencia no estadísticamente significativa (p=1.00). La reducción del CFT fue de 259±239.62μm en el Grupo 1 (p=0.0002) y de 118±148.33μm en el Grupo 2 (p=0.003), siendo esta diferencia no estadísticamente significativa (p=0.06). Los pacientes del Grupo 1 recibieron una media de 4.83±1.79 inyecciones de antiVEGF, y los del Grupo 2, 5.4±1.76 inyecciones, siendo esta diferencia no estadísticamente significativa (p=0.332). CONCLUSIONES: Las inyecciones intravítreas repetidas de antiVEGF en pacientes con EMD inducen el DVP en un 37.9% de los casos con AVM. La presencia de DVP no mejora la eficacia del tratamiento con antiVEGF, al contrario, encontramos una tendencia a una mayor reducción del CFT en pacientes con AVM. Los pacientes con EMD y DVP no requieren menos inyecciones de antiVEGF durante un año.
RATIONALE: One of the first-line treatments of diabetic macular edema (DME) are intravitreal injections of vascular endothelial growth factor inhibitor (antiVEGF) drugs. The high clinical, social and economic impact of this pathology has increased interest in the detection of prognostic biomarkers of response to treatment in order to improve the individualization of treatment, reducing the burden of care in ophthalmology departments. Posterior vitreous detachment (PVD) in patients diagnosed with DME is a poorly studied event, however, published studies agree on a lower rate of DVP in patients with DME than in patients without DME. OBJECTIVES: To demonstrate that intravitreal injections of antiVEGF drugs in patients with DME induce PVD, to demonstrate that the presence of PVD in patients with DME improves the efficacy of antivEGF injection therapy, and to demonstrate that the presence of PVD reduces the number of injections of Anti-VEGF necessary DME treatment. MATERIAL AND METHODS: An observational, prospective and longitudinal study was performed comparing two groups based on presence (Group 1: 18 eyes) or absence (Group 2: 20 eyes) of vitreomacular adhesion (VMA) at 12 months follow-up. The study protocol consisted of visits every 2 months for 1 year, evaluating visual acuity (VA), foveal thickness (CFT) and PVD grade in each visit. The treatment regimen consisted of a fixed regimen of 3 intravitreal injections of Ranibizumab every 2 months, followed by a bimonthly pro re nata regimen. We also included a control group of 10 eyes of diabetic patients without EMD to analyze the incidence of PVD at one year of follow-up. RESULTS: At baseline, 76.32% of the patients had VMA, and at month twelve, a PVD event rate of 37.9% was observed in patients who had received intravitreal injections of antiVEGF while no cases were seen in the control group (P <0.001). The VA improvement was 6.94 letters in Group 1 (p=0.03) and 4.9 letters in Group 2 (p=0.08), this difference being not statistically significant (p = 1.00). CFT reduction was 259±239.62μm in Group 1 (p = 0.0002) and 118±148.33μm in Group 2 (p = 0.003), this difference being not statistically significant (p = 0.06). Patients in Group 1 received an average of 4,83±1,79 injections of anti-VEGF, and those in Group 2, 5.4±1.76 injections, this difference being not statistically significant (p=0.332). CONCLUSIONS: Repeated intravitreal injections of antiVEGF in patients with DME induce PVD in 37.9% of cases with VMA. The presence of PVD does not improve the efficacy of antiVEGF treatment; on the contrary, we found a tendency towards a greater reduction of CFT in patients with VMA. Patients with DME and PVD do not require fewer injections of anti-VEGF for one year.
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Berk, Benjamin-Andreas. "Brain-derived neurotrophic factor-induzierte neuroprotektive Osmoregulation der Müller-Gliazelle der Rattenretina." Doctoral thesis, Universitätsbibliothek Leipzig, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-170385.

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Einleitung: Die Ausbildung eines Netzhautödems ist eine Hauptursache für die Verschlechterung des Sehvermögens bei ischämisch-hypoxischen und inflammatorischen Netzhauterkrankungen. Neben der erhöhten Permeabilität der Blut-Retina-Schranke trägt eine Wasserakkumulation in Netzhautzellen zur Ausbildung eines Netzhautödems bei. Müllerzellen regulieren die retinale Ionen- und Osmohomöostase, indem sie einen transzellulären Ionen- und Wassertransport vermitteln. Zudem kontrollieren Müllerzellen die Größe des Extrazellularraumes, indem sie bei neuronaler Aktivität eine Zellkörperschwellung – ausgelöst durch eine Verkleinerung der extrazellulären Osmolarität – verhindern. Unter pathologischen Bedingungen ist die Volumenregulation gestört, sodass Müllerzellen bei Hypoosmolarität anschwellen. Diese Müllerzellschwellung und eine Glutamat-induzierte Schwellung retinaler Neurone tragen zur Ausbildung eines zytotoxischen Netzhautödems bei. Neuroprotektive Faktoren wie BDNF (brain-derived neurotrophic factor) und bFGF (basic fibroblast growth factor) stimulieren das Überleben retinaler Neurone und verzögern so die retinale Degeneration. Zielstellung: Es war zu zu ermitteln, ob BDNF die zytotoxische Schwellung von Müller- und Bipolarzellen der Rattennetzhaut verhindert. Material und Methoden: Es wurden Netzhautschnitte und isolierte Müller- und Bipolarzellen von 55 adulten Long-Evans-Ratten (durchschnittlich 8-15 Zellen pro Versuchsreihe) verwendet. Eine osmotische Schwellung von Müller- und Bipolarzellen wurde durch eine Superfusion der Schnitte oder der Zellen mit einer 60%igen hypoosmolaren Lösung in Ab- oder Anwesenheit von Bariumchlorid induziert. Die maximale Querschnittsfläche von Müller- und Bipolarzellsomata wurde vor und nach einer vierminütigen Superfusion mit einem konfokalen Laserscanningmikroskop aufgezeichnet. Die nach der Superfusion ermittelte Querschnittsfläche wurde zu den anfänglich gemittelten Kontrollwerten in Beziehung gesetzt und prozentual als Mittelwert mit Standardfehler bestimmt. Mit Hilfe des Prism-Statistikprogramms (Graphpad) wurden die Ergebnisse mittels einem one-way ANOVA Test und einem nachfolgenden Bonferroni\'s multiple comparison Test sowie durch einen Mann-Whitney U Test statistisch analysiert. Ergebnisse: Bei Anwesenheit von BDNF wurde die osmotische Schwellung von Müllerzellen konzentrationsabhängig sowohl in Netzhautschnitten als auch in isolierten Zellen inhibiert. Ebenso inhibierte BDNF konzentrationsabhängig die Schwellung von Bipolarzellen in Netzhautschnitten, jedoch nicht in isolierten Zellen. In Schnitten von postischämischen Netzhäuten bewirkte BDNF eine Schwellungsinhibition von Müllerzellen, nicht aber von Bipolarzellen. Mit pharmakologischen Blockern wurde die durch BDNF induzierte Signalkaskade untersucht. Die BDNF-Schwellungsinhibition von Müllerzellen wurde durch eine Aktivierung von TrkB bewirkt. Die TrkB-Aktivierung führte in Müllerzellen zu einer Transaktivierung von FGF-Rezeptoren sowie zu einer Aktivierung einer glutamatergen-purinergen Signalkaskade, von der bekannt ist, dass sie die osmotische Müllerzellschwellung unterdrückt. Da bFGF die osmotische Müllerzellschwellung inhibiert, wird die Transaktivierung der FGF-Rezeptoren wahrscheinlich durch eine BDNF-induzierte Freisetzung von bFGF aus Müllerzellen vermittelt. Die Ergebnisse lassen vermuten, dass BDNF indirekt auf Bipolarzellen wirkt, indem es eine Freisetzung von Faktoren wie bFGF aus Müllerzellen induziert. Schlussfolgerungen: Die Schwellungsinhibition von Müller- und Bipolarzellen könnte ein neuroprotektiver Mechanismus von BDNF in der Netzhaut darstellen. Während BDNF direkt TrkB auf Müllerzellen aktiviert, ist die Inhibition der Bipolarzellschwellung indirekt und durch die Ausschüttung von glialen Faktoren wie bFGF vermittelt. Der Verlust des Effektes von BDNF auf die Bipolarzellschwellung in ischämischen Netzhäuten könnte darauf zurückzuführen sein, dass gliotische Müllerzellen keine glialen Faktoren mehr in Reaktion auf BDNF freisetzen. Der Verlust des glialen Einflusses auf die Bipolarzellvolumenhomöostase könnte zur Neurodegeneration in der ischämischen Netzhaut beitragen
Introduction: Tissue edema is a major blinding complication of ischemic-hypoxic and inflammatory retinal diseases. In addition to the hyperpemeability of the blood-retinal barrier, water accumulation in retinal cells resulting in cellular swelling may contribute to the development of retinal edema. Müller glial cells regulate the retinal ion and water homeostasis by allowing transcellular ion and water fluxes. During neuronal activity Müller cells control the extracellular space volume by autocrine inhibition of cellular swelling caused by the reduction of extracellular osmolarity. However, under pathological conditions, Müller cells are not capable to regulate their volume so that they swell rapidly under hypoosmolarity. The osmotic swelling of Müller glial cells and the glutamate induced swelling of retinal neurons contribute to the development of cytotoxic retinal edema. Various neuroprotective factors including brain-derived neurotrophic factor (BDNF) and basic fibroblast growth factor (bFGF) stimulate the survival of retinal neurons and thus delay the retinal degeneration. Objective: The objective of the study is to determine whether BDNF inhibits the osmotic swelling of Müller and bipolar cells of the rat retina. Material and Methods: Retinal slices and freshly isolated Müller and bipolar cells of 55 adult Long-Evans rats (in average 8-15 cells per trial) were used. Osmotic swelling of Müller and bipolar cells was induced by superfusion of retinal slices or isolated cells with a 60% hypoosmotic extracellular solution in the absence or presence of barium chloride. The maximal cross-sectional area of Müller and bipolar cell somata was recorded before and after a four minute-long superfusion by using a laser scanning microscope. To determine the extent of cell soma swelling, the cross-sectional area of the cell body extent after superfusion was related to the former averaged cross-sectional area. Results were given as means with standard error as percent values. Statistical analysis was made with Prism (Graphpad) and the significance was determined by the One-way ANOVA test followed by Bonferroni\'s multiple comparison test and the Mann-Whitney U test, respectively. Results: We found that BDNF inhibits dose-depending the osmotic swelling of Müller cells in retinal slices and of isolated cells. BDNF also inhibited dose-depending the osmotic swelling of bipolar cells in retinal slices; however, it did not inhibit the osmotic swelling in isolated bipolar cells. In slices of postischemic retinas, BDNF inhibited the swelling of Müller cells but not the swelling of bipolar cells. The BDNF induced signal transduction cascade was examined by simultaneous administration of blocking agents with the receptor agonists in the hypoosmotic solution. The BDNF-induced inhibition of the osmotic Müller cell swelling was mediated by activation of TrkB. Activation of TrkB in Müller cells results in transactivation of FGF receptors and in an activation of a glutamatergic-purinergic signal transduction cascade which is known to inhibit the osmotic swelling of the cells. Since bFGF also inhibits the osmotic swelling of Müller cells, it can be assumed that the transactivation of FGF receptors is mediated by a BDNF-induced release of bFGF from Müller cells. The results suggest that the effect of BDNF on bipolar cells is indirect by inducing a subsequent release of glial factor from Müller cells such as bFGF. Conclusion: The results show that BDNF inhibits the osmotic swelling of Müller and bipolar cells. The inhibition of cytotoxic cell swelling may contribute to the neuroprotective action of BDNF in the retina. While BDNF acts directly in Müller cells, the BDNF-induced inhibition of the bipolar cell swelling is indirect and mediated by the release of glial factors such as bFGF from Müller cells. The abrogation of the BDNF-induced inhibition of the osmotic bipolar cell swelling in the postischemic retina could be explained with the impairment of the release of glial factors by Müller cells. The abrogation of the Müller cell-mediated regulation of the bipolar cell volume could contribute to the neuronal degeneration in the ischemic retina
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RASSI, Alan Ricardo. "Estudo das alterações retinianas em olhos de coelhos após injeções intravítreas seriadas de infliximabe." Universidade Federal de Goiás, 2011. http://repositorio.bc.ufg.br/tede/handle/tde/1523.

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The objective of this study was to determine the levels of toxicity of two and three intravitreous injections of infliximab to the retina and choroid of albino rabbits by means of histological, electroretinographic and clinical ophthalmological tests. Twelve New Zealand albino rabbits (24 eyes) were used in the study. Each eye was given two (n=10) or three (n=10) serial intravitreous 2 mg injections of infliximab dissolved in 0.06 ml of saline, at monthly intervals. A separate group of rabbits (n=4 eyes) served as a control group. Ninety days after the first injection, the rabbits underwent electroretinographic and clinical ophthalmological tests. After being enucleated, the eyes underwent histological examination. No clinical ophthalmologic abnormalities were detected in the 24 eyes studied. The histological change noted was the presence of rare lymphocytes and eosinophiles in the posterior vitreous of four eyes subjected to two injections and six eyes subjected to three injections of infliximab, but it was not considered clinically significant. One clinically significant abnormality was found, a severe inflammatory reaction with vitreous exudates and ganglion cell edema in both eyes of a single rabbit, subjected to two to three injections of infliximab. The electroretinographic tests showed amplitudes that were on the average 12% smaller than those obtained before the treatment. However, there were no statistically significant differences when comparing amplitude or the implicit time between the pre and post-treatment electroretinographic findings, in all groups examined. Then, two and three intravitreous 2 mg injections of infliximab in eyes of rabbits at monthly intervals did not cause any changes after a 90-day follow-up, according to histological, electroretinographic tests and clinical ophthalmological evaluation. It was concluded that serial intravitreous infliximab doses to rabbits is a safe procedure.
O objetivo deste trabalho foi determinar os níveis de toxicidade de duas e três aplicações intravítreas de infliximabe na retina e coroide de coelhos albinos, por meio de exames clínicos oftalmológicos, eletrorretinográficos e histológicos. Foram utilizados doze coelhos albinos (24 olhos) da raça New Zealand. Cada olho recebeu duas (n=10 olhos) ou três (n=10 olhos) injeções intravítreas seriadas de 2 mg de infliximabe dissolvidos em 0,06 ml de solução salina, em intervalos mensais. Um grupo separado de olhos (n=4 olhos) serviu como controle. Noventa dias após a primeira injeção, os coelhos foram novamente submetidos a exames clínicos oftalmológicos e eletrorretinográfico e, após enucleados, os olhos foram submetidos a exame histológico. Nos 24 olhos estudados, não foram detectadas alterações clínicas oftalmológicas. A alteração histológica notada foi a presença de raros linfócitos e eosinófilos na região posterior do vítreo de quatro olhos submetidos a duas aplicações e de seis olhos que receberam três aplicações de infliximabe, mas sem significado clínico. Foi encontrada uma única alteração clinicamente significante, caracterizada como reação inflamatória grave, com presença de exsudatos vítreos nos dois olhos de um coelho, que foi submetido a duas e três aplicações de infliximabe. Os exames eletrorretinográficos mostraram amplitudes em média 12% menores do que aquelas obtidas antes do tratamento, porém sem diferenças estatisticamente significantes, comparando-se a amplitude ou o tempo implícito entre os achados eletrorretinográficos pré e pós-tratamento em todos os grupos examinados. Assim, duas e três aplicações intravítreas de infliximabe em olhos de coelhos em intervalos mensais, na dosagem de 2 mg, não provocaram alterações após seguimento de noventa dias, quer no exame histológico, na eletrorretinografia ou na avaliação clínica oftalmológica. Conclui-se que doses seriadas de infliximabe por via intravítrea em coelhos é um procedimento seguro.
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Pitard, Irène. "Analyse du mécanisme d'action d'inhibiteurs ciblant l'activation allostérique du facteur œdématogène de Bacillus anthracis." Electronic Thesis or Diss., Sorbonne université, 2020. http://www.theses.fr/2020SORUS420.

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Le facteur œdémateux (EF), une toxine majeure de Bacillus anthracis, est activé par la calmoduline de l’hôte (CaM) pour produire des concentrations supra physiologiques d'AMP cyclique (AMPc) conduisant à une perturbation des voies de signalisation. L'interaction EF-CaM induit des changements conformationnels dans une région switch allostérique de EF conduisant à la formation du site catalytique fonctionnel. Des études antérieures in silico ciblant cette région switch, complétées par des données expérimentales, ont montré que les uréidoacides thiophènes (TUA) inhibent l’activité enzymatique de EF. Cependant, les connaissances sur le site de liaison et sur l'interaction étaient manquantes. Nous présentons ici une étude de l'interaction du TUA-diCl, le composé le plus actif, avec les protéines EF, CaM et le complexe EF-CaM à l'aide d’essais biochimiques couplés à des méthodes biophysiques et de modélisations moléculaires. Le TUA-diCl interagit avec EF isolé, le complexe EF-CaM et de manière inattendue avec CaM. L’étude du site de liaison entre le composé TUA-diCl et la protéine CaM par RMN indique que le composé se lie aux patchs hydrophobes de CaM qui deviennent accessibles lorsque la CaM est complexée par les ions calciums. Ceci entraîne un compactage de la structure de CaM et des changements de la dynamique interne de la protéine. Les données enzymatiques, de fluorescence et de RMN montrent que l'inhibition d'EF est due à l'interaction du composé sur EF et ne dépend pas de la présence de CaM. Des expériences de compétition entre le TUA-diCl et l’inhibiteur du site catalytique EF 2’-MANT-3’-dATP, indiquent que TUA-diCl est un inhibiteur allostérique de EF. Les expériences HDX-MS ont révélé que le TUA-diCl se lierait au domaine hélicoïdal de EF, une région critique pour l'insertion de CaM. De plus, des approches in silico ont mis en évidence plusieurs sites de liaison possible dans le domaine hélicoïdal. Par conséquent, TUA-diCl représente une nouvelle classe d'inhibiteurs de EF avec un mécanisme d'action allostérique et ouvrant la voie vers la conception de molécules thérapeutiques innovantes
Edema factor (EF), a major Bacillus anthracis toxin, is activated by host calmodulin (CaM) to produce supraphysiological concentrations of cyclic AMP (cAMP) thus perturbing intracellular signaling. The EF-CaM interaction induces conformational changes in an allosteric switch region of EF that lead to the formation of the catalytic site. Previous in silico studies targeting this switch region, complemented with experimental data, showed that thiophen ureidoacids (TUA) inhibit the enzyme catalytic activity. However, knowledge of the binding site and inhibition mode of TUA compounds are still lacking. Here, we characterize the interaction of the most active TUA compound (TUA-diCl) with EF, CaM and EF-CaM using biochemical assays coupled to biophysical methods and molecular modeling. We show that TUA-diCl interacts with EF, EF-CaM and unexpectedly with CaM. Mapping of the binding site by NMR, showed that TUA-diCl binds to the exposed hydrophobic patches of calcium loaded CaM, causing the compaction and changes in internal dynamics of the protein. Importantly, enzymatic, fluorescence and NMR data show that EF inhibition is due to the interaction of the compound with EF and is CaM-independent. Furthermore, competition experiments between TUA-diCl and the EF catalytic-site inhibitor 2’-MANT-3’-dATP, indicate that TUA-diCl is an allosteric inhibitor of EF. HDX-MS identifies a putative binding site of TUA-diCl on the helical domain of EF, a critical region for CaM insertion. Several possible binding pockets in the helical domain are analyzed in silico. TUA-diCl represents a new class of EF inhibitors with an allosteric mechanism, opening the way towards the design of innovative therapeutic compounds
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Sandra, Jovanović. "Uloga inhibitora vaskularnog endotelnog faktora rasta u terapiji dijabetičnog makularnog edema." Phd thesis, Univerzitet u Novom Sadu, Medicinski fakultet u Novom Sadu, 2015. http://www.cris.uns.ac.rs/record.jsf?recordId=91828&source=NDLTD&language=en.

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Dijabetesna retinopatija je među vodećim uzročnicima stečenog slepila, kako u razvijenim zemljama, tako i zemljama u razvoju. Dijabetesna retinopatija je jedna odnajčešćih komplikacija Dijabetes Mellitus-a. U sklopu dijabetesne retinopatije jedan od najranijih razloga koji dovodi do pada vidne oštrine je dijabetični makularni edem (DME). Pad vidne oštrine kod pacijenata sa dijabetesom narušava njihov kvalitet života i umanjuje radnu sposobnost. Dosadašnji oblik lečenja laserfotokoaguacijom makule, nije dao zadovoljavajuće rezultate. U novije vreme sve više je zastupljeno farmakološko lečenje edema koje podrazumeva intrvitrealnu aplikaciju lekova iz grupe inhibitora vaskularnog endotelnog faktora rasta (VEGF inhibitori), koji dovodi do stabilizacije zidova krvnih sudova. Cilj ove studije je da se ispita efikasnost lečenja DME uz pomoć intravitrealno aplikovanih lekova iz grupe inhibitora vaskularnog endotelnog faktora rasta u odnosu na konvencionalno do sada priznato lečenje laserfotokogulacijom makule. Efikasnost lečenja je procenjivana na dva načina: anatomski, na osnovu smanjenja centralne makularne debljine izražene u μm, merene metodom optičke koherentne tomografije, i funkcionalno, na osnovu poboljšanja vidne oštrine koja je izražavana u log MAR jedinicama. U ovoj prospektivnoj, randomiziranoj kliničkoj studiji sa minimumom praćenja od 6 meseci, u eksperimentalnoj grupi tretiran je 51 pacijent,odnosno 84 oka aplikacijom bevacizumaba (anti VEGF agens) u dozi od 1,25 mg, sa ili bez dodatnog laser tretmana. Uz prosečno 2,46 inekcije postignuta je prosečna redukcija centralne makularne debljine od 139,15 μm.  Dobijene vrednosti su nakon svake aplikovane doze su značajno bolje u odnosu na početnu. Edemi sa većom centralnom makularnom debljinom su zahtevali tretman sa većim brojem inekcija. Kod većih edema je postignuta i veća redukcija centralne makularne debljine. U odnosu na vidnu oštrinu u eksperimentalnoj grupi postignuto je poboljšanje od 0,135 log MAR jedinica. Efekat lasera kao samostalne terapije u kontrolnoj grupi (50 pacijenata, 92 oka) nije bioznačajan ni u pogledu smanjenja centralne makularne debljine kao ni na osnovu poboljšnja vidne oštrine. Tretman bevacizumabom samostalno ili u kombinaciji sa laserom je efikasniji u tretmanu DME u odnosu na konvencionalni tretman laserfotokoaguacijom koji potvrđeno dovodi do stabilizacije stanja. Značaj ove studije je potvrda efikasnosti i bezbednosti jednog novog oblika lečenja koji samostalno ili u kombinaciji sa laser tretmanom predstavlja novi protokol lečenja dijabetičnog makularnog edema.
Diabetic retinopathy is among the leading causes of acquired blindness in developed countries, as well as in developing countries. Diabetic retinopathy is one of the most frequent Diabetes Mellitus complications. Within diabetic retinopathy, diabetic macular edema (DME) is one of the earliest causes of the loss of visual acuity. Impaired vision causes decline in life quality in diabetic patients and it decreases theirworking ability. Up to this date, laser photocoagulation treatment has not givensatisfactory results. Recently, new promising treatment forms have emerged, including the intravitreal application of vascular endothelium growth factor (VEGF inhibitors), which lead to stabilization of the vessel wall. The aim of this study is to evaluate the efficacy of DME treatment consisting of intravitreal  VEGF inhibitor application alone or as a part of combined treatment (intravitreal VEGF inhibitor plus laser photocoagulation) compared with conventional laser treatment alone. The effect of treatment was evaluated according to morphological parameters by measuring central macular thickness (CMT) in μm with optical coherence tomography, and according to functional parameter by visual acuity in log MAR scale. In this prospective randomized clinical trial, with minimum follow up of 6 months, in experimental group 51 patient, or 84 eyes were treated with bevacizumab (VEGF inhibitor) in 1.25 mg dosage, alone or in combination with laser. The mean reduction in was 139.15 μm, which was achieved with 2.46 doses on average. The difference between the final and initial CMT values after each dos age was tatistically significant.Edemas with high central macular thickness required high number of intravitealaplicatons and the reduction was higher. In our study, mean visual acuity improved significantly in 0.135 log MAR. In control group (50 patient, 92 eyes) treated with laserphotocolagulation alone, the effect on visual acuity and central acular thickness was not statistically significant. The treatment with bevacizumab alone or in combinedtreatment is more effective in treating DME than conventional macular laser treatment alone, from both - anatomical and functional perspective. The importance of this study is confirmation of the efficacy and safety of a new form of treatment and the introduction of a new protocol for the treatment of diabetic macular edema.
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McCafferty, Sean, April Harris, Corin Kew, Tala Kassm, Lisa Lane, Jason Levine, and Meisha Raven. "Pseudophakic cystoid macular edema prevention and risk factors; prospective study with adjunctive once daily topical nepafenac 0.3% versus placebo." BIOMED CENTRAL LTD, 2017. http://hdl.handle.net/10150/623120.

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Background: Define the effectiveness of a topical non-steroidal anti-inflammatory drug (NSAID) added to topical steroid use after uncomplicated phacoemulsification for the prevention of pseudophakic cystoid macular edema (PCME) using a prospective, randomized, double-masked, placebo-controlled clinical study. Methods: Eyes (1000) were randomized to placebo (497) or nepafenac 0.3% (503) used once daily, post-operatively for 5 weeks at two ophthalmology clinics. Diagnosis of PCME was made by clinical, ocular coherence tomography (OCT), and with fluorescein angiography confirmation. Correlation of PCME to NSAID use and the presence of pre-operative risk factors for PCME were assessed including, contralateral PCME, diabetic retinopathy, retinal vein occlusion, macular hole, epiretinal membrane, macular degeneration, retinal detachment repair, and prostaglandin use. Results: PCME was the most common complication associated with routine cataract surgery (4.2% with PCME risk factors, 2.0% with risk factors excluded). Topical nepafenac 0.3% significantly reduces the incidence of PCME compared to placebo when used after routine cataract surgery (p = .0001). When patients with pre-operative risk factors are excluded, the incidence of PCME between treatment and placebo groups is equivalent (p = 0.31). PCME relative risk (RR) was most significant in contralateral PCME (RR 19.5), diabetic retinopathy (RR 13.1), retinal vein occlusion (RR 12.9), macular hole (RR 7.7), and epiretinal membrane (RR 5.7). Prostaglandin use and previous retinal detachment were not shown to increase risk. Conclusion: Pseudophakic cystoid macular edema is common after phacoemulsification cataract surgery. Topical nepafenac 0.3% reduces PCME in patients with pre-operative risk factors for PCME compared to placebo but shows no benefit in patients without pre-operative risk factors.
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Rud, Nicole Ann. "Environmental factors influencing the physiological disorders of edema on ivy geranium (Pelargonium peltatum) and intumescences on tomato (Solanum lycopersicum)." Thesis, Manhattan, Kan. : Kansas State University, 2009. http://hdl.handle.net/2097/2380.

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Figueras, Roca Marc. "Caracterització dels Factors Clínics i Biològics Associats a l’Edema Macular Diabètic en la Diabetis Mellitus Tipus II." Doctoral thesis, Universitat de Barcelona, 2018. http://hdl.handle.net/10803/663845.

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INTRODUCCIÓ: L'edema macular diabètic (EMD) és una complicació clínica associada a la retinopatia diabètica (RD) i és la primera causa de pèrdua visual en diabètics en el món desenvolupat. Implica l'extravasació de fluids i lípids en l'àrea macular, la regió de la retina responsable de la visió central. Alguns dels seus factors de risc, com la hiperglucèmia crònica, són comuns amb la RD. Tanmateix, altres agents claus en la seva etiopatogènia, com els mediadors moleculars de la inflamació i diferents factors de creixement, no han estat estudiats en profunditat, especialment en relació amb la seva presència diferencial lligada a l'existència d'EMD. OBJECTIU: Estudiar l'associació entre factors metabòlics i inflamatoris en sang perifèrica i la presència d'EMD així com la seva associació a certes característiques intraoculars. MATERIALS I MÈTODE: Es planteja un estudi observacional de tall transversal sobre pacients diabètics amb RD en dos grups, aquells amb EMD associat (n=58) i aquells sense EMD (n=18). Es va realitzar un estudi detallat de la presentació oftalmològica en aquests grups d'acord als criteris d'inclusió i exclusió establerts, incloent diferents paràmetres qualitatius i quantitatius de tomografia de coherència òptica macular (OCT) a tots els pacients i angiografia fluoresceínica retinal de camp ampli (AFCA) en els casos d'EMD. A més a més, es va dur a terme un estudi complet de factors metabòlics (glicèmia, creatinina, colesterol total, LDL colesterol, HDL colesterol, triglicèrids, enzims hepàtics, hemoglobina i hemoglobina glicada) mitjançant anàlisi sanguínia així com de mediadors inflamatoris sèrics (citocines, quimiocines i factors de creixement), també en tots els pacients. El panell de mediadors inflamatoris estudiat, d'acord al coneixement previ disponible tant en mostres sanguínies com intraoculars, inclogué: IL-1β, IL-3, IL-6, IL-8, IL-10, MCP-1, IP-10, IFN-γ, TNF-α i VEGF. RESULTATS: Els paràmetres metabòlics i inflamatoris sèrics estudiats no s'han associat directament a la presència d'EMD. Tanmateix, quan aquesta complicació intraocular està present, certes característiques de la mateixa s'associen de forma estadísticament significativa a determinats mediadors sistèmics: la presència d'engruiximent difús de la retina per OCT es relaciona amb majors xifres sèriques d'IL-6; l'existència d'edema macular quístic per OCT s'associa a menors nivells en sang perifèrica d'IL-10; i, finalment, s'han objectivat majors xifres sèriques d'IL-8 i VEGF en aquells casos amb augment de la zona avascular foveal mesurada per AFCA. CONCLUSIÓ: El desenvolupament d'EMD no s'associa aparentment a patrons diferenciats de mediadors inflamatoris o metabòlics pel que fa a sang perifèrica. Tanmateix, certes característiques anatòmiques de l'EMD sí que es relacionen amb determinades molècules en l'àmbit sistèmic. Tot i el seu caràcter pilot, aquests resultats aporten valuosa informació sobre les que proposar estratègies futures en el maneig individualitzat del pacient amb EMD.
INTRODUCTION: Diabetic macular edema (DME) represents a clinical complication of diabetic retinopathy (DR) and is the major cause of vision loss in diabetic patients in the developed world. It implies fluid and lipid extravasation in the macular area of the retina, which is accountable of main visual acuity. Several DME risk factors, as chronic hyperglycemia, are common to DR. However, other etiopathogenic agents such as inflammatory molecules and growth factors have not been widely studied, specially regarding its differential association to DME. AIMS: To study the association between peripheral blood metabolic and inflammatory factors and presence of diabetic macular edema (DME) and its related anatomic features in type 2 diabetic mellitus (T2DM) patients. MATERIAL AND METHODS: Observational cross-sectional study on a proof of concept basis. Seventy-six T2DM included patients were divided based on the presence (n = 58) or absence of DME (n = 18) according to optical coherence tomography (OCT). Ultra-widefield fluorescein angiography (UWFA) was performed in DME patients. Fasting peripheral blood sample testing included glycemia, glycated hemoglobin, creatinin and lipid levels among others. Serum levels of a broad panel of cytokines and inflammatory mediators were also analyzed. OCT findings included central subfoveal thickness, diffuse retinal thickness (DRT), cystoid macular edema (CME), serous retinal detachment and epirretinal membrane. UWFA items included pattern of DME, presence of peripheral retinal ischemia and enlarged foveal avascular zone (FAZ). RESULTS: Metabolic and inflammatory factors did not statistically differ between groups. However, several inflammatory mediators did associate to certain ocular items of DME cases: IL-6 was significantly higher in patients with DRT (p = 0.044), IL-10 was decreased in patients with CME (p = 0.012), and higher IL-8 (p = 0.031) and VEGF levels (p = 0.031) were observed in patients with enlarged FAZ. CONCLUSION: Inflammatory and metabolic peripheral blood factors in T2DM may not be differentially associated to DME when compared to non-DME cases. However, some OCT and UWFA features of DME such as DRT, CME and enlarged FAZ may be associated to certain systemic inflammatory mediators.
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Correia, Diogo Jorge Durais. "AVC Hemorrágico." Master's thesis, Universidade da Beira Interior, 2009. http://hdl.handle.net/10400.6/906.

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Introdução: O acidente vascular cerebral hemorrágico pela sua epidemiologia, e pelos seus altos índices de mortalidade, exige uma resposta rápida e incisiva para que os doentes recebam o melhor tratamento possível. Para que a resposta seja efectiva, há que reconhecer os factores de risco e os factores passíveis de alterar a mortalidade precoce (primeira semana) por esta causa. Foi neste sentido que o estudo foi desenhado, para identificar factores de risco passíveis de alterar o resultado final perante doentes com acidente vascular cerebral hemorrágico, dando especial atenção ao volume inicial de hemorragia e edema como factores de mau prognóstico. Métodos: Recolheram-se os dados do suporte informático da tomografia computorizada crâneo-encefálica de entrada e dos processos clínicos dos doentes internados na Unidade de Acidentes Vasculares Cerebrais do Hospital Pêro da Covilhã entre o dia 1 de Setembro de 2007 e o dia 31 de Agosto de 2008. Resultados: O estudo envolveu 45 doentes, 33 destes sobreviveram e 12 resultaram em óbito. A mortalidade deste grupo de estudo foi de 26,7%. Os doentes que faleceram apresentaram um valor médio de volume de hemorragia de 31,4cc, enquanto os restantes doentes tinham um valor médio de 15,7cc. O valor médio de volume de edema nos doentes que faleceram foi de 31,4cc, e nos outros doentes a média foi de 12,8cc. Discussão: Maior volume inicial de edema nas primeiras 24 horas está associado a risco independente de mortalidade precoce por acidente vascular cerebral hemorrágico. Contagem de plaquetas e nível aumentado de glicemia à admissão hospitalar, bem como história de diabetes mellitus, de fibrilhação auricular e de uso prévio de medicação antiagregante, estão também independentemente associados a pior prognóstico.
Introduction: Taking into account hemorrhagic stroke epidemiology, and its high mortality rate, a quick and incisive response is needed so that patients can receive the best possible treatment. In order to do so, it’s vital to recognize risk factors and the factors that can alter early death (first week) in this context. This study was designed to respond to that need, to identify risk factors capable of altering the outcome of hemorrhagic stroke patients, with special attention given to initial hemorrhagic volume and initial oedema volume as poor prognostic factors. Methods: The data was collected from the digital support of the cranial computerized tomography and from the clinical records of the patients admitted on “Unidade de Acidentes Vasculares” of Pêro da Covilhã Hospital between September 1, 2007 and October 31, 2008. Results: The study included 45 patients, 33 of which survived and 12 died. The mortality of the group was 26,7%. The patients that died showed a mean volume of haemorrhage of 31,4cc, while the others stayed with a mean volume of 15,7cc. The mean value for oedema volume in the deceased patients was 31,4cc, and 12,8 in the ones who survived. Discussion: Higher volume of oedema in the first 24 hours is associated with independent risk for early mortality following hemorrhagic stroke. Platelet count and higher glucose level on admission, as well as history of diabetes mellitus, atrial fibrillation and prior use of antiplatelet agents are also independently associated with worst prognosis.
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Der, Nigoghossian Marilyn. "Vers l’élucidation des mécanismes d’action des molécules utilisées contre l’oedème maculaire." Thesis, Paris 5, 2014. http://www.theses.fr/2014PA05P634.

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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
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Sentenac, Pierre. "Hypertension pulmonaire et remodelage cardiaque en lien avec l’hyper-débit survenant après chirurgie de résection pulmonaire : physiopathologie, mécanismes cellulaires et moléculaires, nouvelles thérapies ciblées." Thesis, Montpellier, 2020. http://www.theses.fr/2020MONTT034.

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L'objectif était d'étudier le remodelage vasculaire pulmonaire après pneumonectomie droite (PN) chez le rat, et d'explorer in vitro les mécanismes impliqués sur des cellules humaines soumises à un shear stress. Chez les patients, l'objectif était de déterminer l'incidence de dysfonctionnement ventriculaire droite (VD) précoce après résection pulmonaire majeure, évaluée par le strain longitudinal de la paroi latérale du VD (RVLW).Soixante rats mâles Sprague-Dawley ont subi soit une PN droite ou une chirurgie sham. Dix rats par groupe ont été sacrifiés au 3ème, 7ème et 28ème jours postopératoires (J3, J7, J28). Les altérations cardio-pulmonaires ont été étudiées par des analyses échocardiographiques, hémodynamiques et histologiques. Un antagoniste compétitif du récepteur β du facteur de croissance dérivé des plaquettes (PDGFR- β), appelé inhibiteur A4, a été administré entre J0 et J28 chez dix rats en prévention de l’HTP. In vitro, le shear stress a été reproduit à l'aide d'un système FlexCell ™ Tension. Un étirement cyclique pathologique (allongement de 18%) a été appliqué sur des cellules endothéliales pulmonaires (P-ECs) humaines pour évaluer l'impact sur la croissance des cellules musculaires lisses artérielles pulmonaires (PA-SMCs). Une étude prospective a été menée au CHU de Montpellier (France). Tous les patients opérés d’une chirurgie de résection pulmonaire majeure, sans hypertension pulmonaire ni dysfonction VD préexistante, étaient éligibles. Une échocardiographie standardisée (GE® Vivid iq ™) a été réalisée en préopératoire puis aux jours 1, 2 et 3 postopératoires par le même examinateur. Le critère d'évaluation était la survenue d'une dysfonction VD définie par un RVLW longitudinal strain supérieur à -15%. La pression artérielle pulmonaire (PAP) moyenne a progressivement augmenté dans le groupe PN pour atteindre 35 ±7 mmHg à J28 vs 18 ±4 (sham) (P=0.001), de même que la proportion d'artères pulmonaires distales muscularisées, 83 ±1% vs 5 ±1 respectivement (P<0.001), liée à une prolifération in situ de PA-SMC. La surface télé-diastolique du VD et l'épaisseur de la paroi latérale VD étaient doublées dans le groupe PN à J28. La fraction d'éjection du ventricule gauche était diminuée à J7 et J28 tandis que la fonction systolique VD était préservée. In vitro, la croissance des PA-SMCs humaines était significativement plus élevée avec le milieu de culture des P-ECs « stretchées » vs « non stretchées ». Cela a permis de mettre en évidence le rôle du shear stress sur la fonction paracrine de la P-EC. Le PDGF était le principal facteur de croissance impliqué. Chez le rat, un traitement par antagoniste du PDGFR-β a diminué la PAP systolique après PN, de 69 ±10 (PN) à 46 ±6 mmHg (PN+A4) (P=0.0005), et l'indice d'hypertrophie du VD de 0.52 ±0.09 à 0.42 ±0.06 respectivement (P=0.004). Entre Février 2017 et Juillet 2018, 110 patients ont été inclus, 92 ont été analysés, âge moyen 65 ±10 ans, 59% d'hommes, BPCO dans 41% des cas, 74 lobectomie (80%), 8 pneumonectomie (9%), 6 bilobectomie (7%). Le RVLW longitudinal strain s’altérait dans les trois premiers jours chez 55% des patients (IC 0.44—0.66), passant de -20 ±7% (J0) à -16 ±6 (J3) (P=0.002). Le strain des segments de la RVLW (basal, moyen et apex) était altéré de manière homogène. Un TAPSE altéré a été observé chez 15% des patients, préférentiellement après pneumonectomie ou bilobectomie qu'après lobectomie (P=0.04). Une HTP survenait chez 11% des patients. CONCLUSIONS: Chez le rat, la pneumonectomie droite a conduit à une HTP liée à une forte muscularisation des artères pulmonaires distales et associait un remodelage sélectif du VD. In vitro, le shear stress a modifié le contrôle paracrine des P-ECs sur la croissance des PA-SMCs. L'inhibitionsélective du PDGFR-β pourrait être une cible thérapeutique. Après chirurgie de résection pulmonaire majeure, le RVLW strain a montré un dysfonction précoce du VD chez environ 50% des patients
The objective was to investigate the consequences of right pneumonectomy (PN) on the pulmonary vascular bed in rats, and to explore in vitro the involved mechanisms in human cells. In patients, the objective was to determine the incidence of right ventricular (RV) dysfunction during the first three days after major pulmonary resection surgery, assessed by the RV lateral wall (RVLW) longitudinal strain, a new marker of RV function.Sixty Sprague-Dawley male rats randomly underwent either a right PN or sham surgery. Ten rats per group were sacrificed on postoperative days 3, 7 and 28 (D3, D7, D28). Cardiopulmonary alterations were investigated by echocardiographic, hemodynamic and histological analyses. A competitive antagonist of the platelet-derived growth factor (PDGF)-receptor β (named A4 inhibitor) was administered between D0 and D28 in ten rats to prevent PH development. In vitro, the shear stress was reproduced using a FlexCell™ Tension system. A pathological cyclic stretch (18% elongation) was applied on cultured human pulmonary endothelial cells (P-ECs) to investigate the impact on pulmonary artery smooth muscle cell (PA-SMC) growth. Growth factors were dosed in P-ECs using qRT-PCR. A prospective study was conducted in the Montpellier University Hospital (France). All patients undergoing a major pulmonary resection surgery, without pre-existing PH or RV dysfunction, were eligible. A standardized echocardiography (GE® Vivid iq™) was performed preoperatively and then on postoperative days 1, 2 and 3 by the same examiner. The endpoint was the occurrence of a RV dysfunction, defined by a RV lateral wall (RVLW) longitudinal strain greater than -15%.Mean pulmonary arterial pressure (mPAP) gradually increased in the PN group to reach 35 ±7 mmHg on D28 vs 18 ±4 in sham (P = 0.001), likewise the proportion of muscularized distal pulmonary arteries, 83 ±1% vs 5 ± 1 respectively (P < 0.001), related to in situ PA-SMC proliferation. The RV enddiastolic area and RV lateral wall thickness were doubled in the PN group on D28. The left ventricle ejection fraction decreased on D7 and D28 while the RV systolic function was maintained. In vitro, the human PA-SMC growth was significantly greater when seeded with stretched vs non stretched P-EC media, highlighting the role of shear stress on the P-EC paracrine function. The qRT PCR highlighted that the PDGF was the main growth factor involved. In rats, a treatment by PDGFR-β antagonist decreased the systolic PAP after pneumonectomy, from 69 ±10 (PN) to 46 ±6 mmHg (PN+A4) (P = 0.0005), and the RV hypertrophy index from 0.52 ± 0.09 to 0.42 ± 0.06 respectively (P = 0.004). Between February 2017 and July 2018, 110 patients were included, 92 were analyzed, mean age 65 ±10 years, 59% male, COPD in 41% of cases, 74 lobectomy (80%), 8 pneumonectomy (9%), 6 bilobectomy (7%). In the early postoperative period, the RVLW longitudinal strain was altered in 55% of patients (CI 0.44—0.66), and dropped from -20 ±7% (D0) to -16 ±6 (D3) (P = 0.002). The longitudinal strain of the RVLW segments (basal, middle and apex) was homogeneously altered. An altered TAPSE (less than 17 mm) was observed in 15% of patients, preferentially after pneumonectomy or bilobectomy than after lobectomy (P = 0.04). Pulmonary hypertension (defined by systolic PAP >35 mmHg) occurred in 11% of patients, and the systolic PAP increased from 19 ±9 (D0) to 21 ±11 (D3) mmHg (P = 0.006). CONCLUSIONS: In rats, right pneumonectomy led to PH related to high muscularisation of distal pulmonary arteries, and was associated with a selective RV remodeling. In vitro, the shear stress related to high blood flow altered the pulmonary endothelial paracrine control of SMC growth. Selective PDGFR-β inhibition could be a therapeutic target. After major pulmonary resection surgery, the RVLW longitudinal strain showed an early RV dysfunction in approximately 50% of patients
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14

Yu-KueiLee and 李昱逵. "Comparative effectiveness research of anti-vascular endothelial growth factor drugs in diabetic macular edema." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/nfum23.

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碩士
國立成功大學
公共衛生研究所碩士在職專班
107
SUMMARY The study analyzes the patient data from the Department of Ophthalmology in National Cheng Kung University Hospital from 2015 to 2017. Three anti–vascular endothelial growth factor (anti-VEGF) medications are Lucentis (ranibizumab), Eylea (aflibercept) and Avastin (bevacizumab). The purposes of the study are comparing the effect of three anti-VEGF medications in treating the patient with diabetic macular edema, finding out the effect of drug half-life, and the possible risk factors which can influence the effect of treatment. The result showed that the effect of drug half-life may be little. Aflibercept is better than ranibizumab in improving best corrected visual acuity (BCVA), logarithm minimal angle resolution (LogMAR), central macular thickness (CMT), and average macular thickness (AMT). There is no significant difference between bevacizumab and ranibizumab. Patients with panretinal photocoagulation may have decline in BCVA and LogMAR and thicker AMT. Patients with tractional macular edema have worse improvement in CMT. INTRODUCTION In the Wisconsin Epidemiologic Study of Diabetic Retinopathy cohort, after 20 years of diabetes mellitus, nearly 99% of patients with type 1 and 60% with type 2 disease demonstrated some degree of diabetic retinopathy. Nowadays, the mainstream treatment for diabetic macular edema is intravitreal anti-VEGF. However, ranibizumab and aflibercept are really expensive. There is another choice: bevacizumab, which is off-label use but much cheaper than ranibizumab and aflibercept. The three goals for this study are as follows: First, compare the effect of three anti-VEGF medications in treating the patients with diabetic macular edema. Second, find out the effect of drug half-life. Third, find out the possible risk factors which can influence the effect of treatment. MATERIALS AND METHODS The study analyzes the patient data from the Department of Ophthalmology in National Cheng Kung University Hospital from 2015 to 2017. Three anti-VEGF medications are ranibizumab, aflibercept and bevacizumab. The study compares the change of visual acuity and macular thickness in different anti-VEGF medications. The study adopts mixed effect model and analyzes the data in two ways. One is to find out the effect of drug half-life. The dependent variable is the difference of data measured before and after the injection. The other is to find out the effect of interaction between three medications and treatment duration time without drug half-life effect. The dependent variable is the data measured after the injection. RESULTS AND DISCUSSION In the model with drug half-life, there is no significant difference in BCVA and LogMAR per injection. In CMT, ranibizumab decreases 101um (P=0.003), aflibercept decreases 102um (P=0.002)、bevacizumab decreases 79um (P=0.014) per injection. In AMT, ranibizumab decreases 42um (P=0.002), aflibercept decreases 42um (P=0.002)、bevacizumab decreases 39um (P=0.011) per injection. In the model without drug half-life, before the treatment start, aflibercept is worse 0.114 in BCVA (P〈0.001), worse 0.165 in LogMAR (P〈0.001), thicker 20 um (P=0.026) in CMT than ranibizumab and no significant difference in AMT with ranibizumab. Bevacizumab is worse 0.079 in LogMAR (P=0.015), thicker 32 um (P=0.001) in CMT, thicker 12 um (P=0.008) in AMT than ranibizumab and no significant difference in BCVA with ranibizumab. The interaction between aflibercept and treat duration time is better than the interaction between ranibizumab and treat duration time in BCVA 0.0002, LogMAR 0.004 (-0.008+0.004), CMT 3.002 um and AMT 1.523 um per month. CONCLUSION In the model with drug half-life, there is no significant difference in BCVA and LogMAR per injection but significant macular thickness decline in CMT and AMT. The difference of macular thickness decline between three drugs needs further test. In the model without drug half-life, aflibercept is better than ranibizumab in improving BCVA, LogMAR, CMT and AMT. There is no significant difference between bevacizumab and ranibizumab. Patients with panretinal photocoagulation may have decline in BCVA and LogMAR and thicker AMT. Patients with tractional macular edema have worse improvement in CMT.
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15

Lee, Po-Yen, and 李柏延. "Amantadine use as a risk factor for corneal edema: a nationwide cohort study in Taiwan." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/93893832988056563109.

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碩士
高雄醫學大學
醫學研究所碩士班
105
Purpose: To evaluate the association between amantadine use and corneal toxicity in a nationwide population. Preface: Few studies have examined the association between the use of amantadine and corneal toxicity. Until now, there are more and more serious studies around the world mentioned this side effect. Specifically, severe corneal edema develops soon after initiation of amantadine therapy and resolves within a few weeks after cessation of amantadine. We previously reported four cases of reversible corneal edema and permanent endothelial loss caused by amantadine use. We hypothesized that use of amantadine may damage the corneal endothelium in a dose-dependent manner. Therefore, this study used the Taiwan Longitudinal Health Insurance Database to investigate the association between amantadine use and corneal edema and to determine the dose that has toxic effects on the endothelium. Design: Retrospective study of nationwide population-based administrative database. Methods: This study analyzed data in the Taiwan Longitudinal Insurance Database for a group of 8195 patients diagnosed with Parkinson''s disease during a 15-year period (January 1, 1996 to December 31, 2010). A control group of 8195 patients without Parkinson’s disease was randomly matched with the Parkinson’s group by age, gender, and comorbidity index. The Kaplan-Meier method was used to calculate the cumulative incidence of corneal edema. Incident rate ratios and Cox proportional hazard regressions were estimated to compare the risk of corneal edema. The same methods were then used to compare the risk between patients with and without amantadine treatment. Results : The incidence of corneal edema in the Parkinson’s group (123 patients; 1.50%) was significantly higher than that in the control group (82 patients; 1.0%) (p = 0.004). The incidence ratio for corneal edema in the Parkinson’s group versus the controls was 5.77. When the Parkinson’s group was further subgrouped by use and non-use of amantadine, the hazard ratio for corneal edema was 1.79 times higher in the amantadine subgroup. Analyses of the amantadine subgroup by cumulative dose revealed that, the 30-day hazard ratio for corneal edema was 2.05 times higher in patients given moderate doses (2000-4000mg) of amantadine, and 2.84 times higher in the subgroup of patients given high doses (>4000 mg). Conclusions: Continuous use of Amantadine increases the risk of corneal edema in a dose-dependent manner. This nationwide, case-control study of a Taiwan cohort found that amantadine treatment is a significant risk factor for corneal edema in patients with Parkinson’s disease. Specifically, a high dose (4000mg) of amantadine administered in a short period (1 month) causes a nearly 3-fold increase in the risk of corneal edema.
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Mohammed, Hesham Hamada Taha [Verfasser]. "Molecular analysis of adenylyl cyclase : Bacillus anthracis edema factor exotoxin / presented by Hesham Hamada Taha Mohammed." 2009. http://d-nb.info/999756400/34.

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17

Leitão, Ricardo Alexandre Gomes. "Role of aquaporin-4 in methamphetamine-induced blood-brain barrier dysfunction and cerebral edema formation." Doctoral thesis, 2017. http://hdl.handle.net/10316/40920.

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Tese de doutoramento em Engenharia Biomédica, apresentada à Faculdade de Ciências e Tecnologia da Universidade de Coimbra
Methamphetamine (METH) is a powerful psychostimulant drug of abuse that has gained worldwide popularity, and its use originates severe health problems. Despite extensive characterization of METH-induced neurotoxicity over the last years, many questions remain unanswered. Several reports have demonstrated that oxidative stress, mitochondrial dysfunction, and neuroinflammation are some of the neurotoxic features of METH. More recently, it was shown that METH compromises the blood-brain barrier (BBB) and causes a disturbance in the water homeostasis leading to brain edema. Additionally, it is well known that astrocytes play a crucial role in modulating BBB structure and function, as well as in regulating brain water content. However, the effect of METH on the crosstalk between brain endothelial cells (ECs) and astrocytes has never been addressed before. Also, water fluxes that take place between the different compartments of the brain, and between brain parenchyma and the blood are highly controlled. Thus, disturbances in this well-regulated homeostasis cause brain edema, which will have deleterious effects on brain function. Importantly, the water transport at BBB is regulated by water channels, aquaporins (AQPs), and AQP4 is the most important at the Central Nervous System, being express on astrocytic endfeet in contact with brain vessels. Brain edema is a hallmark of several neuropathologies, and METH consumption is not an exception. Yet, to date, nothing is known about the role of AQP4 under METH conditions. Furthermore, AQP4 has two isoforms, M1 and M23, and the ratio M1/M23 regulates water homeostasis since M23 stabilizes the channel function but M1 disrupts the AQP4 structure. Taking into consideration all the gaps in this field, it is urgent to clarify the role of AQP4 in METH-induced BBB dysfunction and brain edema formation. The present thesis is divided into 5 chapters. In chapter 1 is presented a review of the literature about the different themes that were explored in the laboratory and detailed in the following chapters. In chapter 2, the impact of METH on astrocytes-ECs crosstalk was investigated with a particular interest in the role of tumor necrosis factor alpha (TNF-α). After observing that METH increased TNF-α released by both astrocytes and ECs, it was also proved that this proinflammatory cytokine was responsible for endothelial permeability through the activation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathway. These in vitro results were corroborated by animal studies showing an increase of BBB permeability and TNF-α levels in the mice striatum, which was prevented by NF-κB pathway blockade. Overall, it was shown that TNF-α/NF-κB signaling pathway has a key role in METH-induced BBB dysfunction. Next, in chapter 3, it was investigated the direct effect of METH on AQP4 system concluding that METH, besides BBB dysfunction, is also able to induce a cytotoxic brain edema and depressive-like behavior. Curiously, AQP4 was shown to have a predominant role of such alterations since its inhibition prevented all the effects observed in mice. Moreover, AQP4 via reactive oxygen species (ROS) production was involved in cell swelling and altered astrocyte morphology triggered by METH since AQP4 knockdown or its pharmacological blockade, as well as an antioxidant treatment (namely vitamin C) were able to prevent METH effects in astrocytes. In conclusion, AQP4 was identified as a new target against METH-induced neurogliovascular dysfunction and depressive-like behavior. Following the results observed in chapter 2 and 3, a new strategy to counteract the negative effects of METH was applied by using a natural flower product. Thus, in chapter 4, it was proved that parthenolide (PTL), a feverfew plant extract, has an anti-inflammatory role and prevented METH-induced BBB permeability and brain edema. Additionally, TNF-α via activation of its receptor 1 (TNFR1) was involved in astrocytic swelling induced by METH. In sum, PTL plays a beneficial role against neuroinflammation and neurogliovascular dysfunction triggered by METH. Finally, in chapter 5, a general discussion is presented. Overall, the present work shows that METH interferes with brain water homeostasis and BBB function, culminating in behavioral abnormalities. Moreover, both neuroinflammation and oxidative stress are involved in such negative effects of METH, and new strategies to counteract these deleterious consequences were identified, such as AQP4 blockade and the use of PTL.
A metanfetamina (MET) é uma droga de abuso muito viciante com grande popularidade mundial, e que causa sérios problemas de saúde. Apesar da extensa caracterização da sua neurotoxicidade nos últimos anos, muitas questões continuam sem resposta. Alguns estudos têm mostrado que o stresse oxidativo, a disfunção mitocondrial e a neuroinflamação são alguns dos efeitos nefastos da MET. Mais recentemente demonstrou-se que a MET interfere com a função normal da barreira hematoencefálica (BHE), causando alterações na homeostase da água o que pode levar a uma situação de edema cerebral. Para além disso, sabe-se também que os astrócitos têm um papel muito importante na modulação da estrutura e função da BHE, bem como na regulação do conteúdo de água cerebral. No entanto, o efeito da MET na comunicação entre as células endoteliais (CEs) e os astrócitos nunca foi estudado anteriormente. Por outro lado, o movimento de moléculas de água entre os diferentes compartimentos do cérebro e entre o parênquima cerebral e a corrente sanguínea ocorre de forma controlada. Assim, distúrbios nesta homeostase irão causar uma situação de edema, o qual terá um impacto negativo na função cerebral. O transporte de água na BHE é regulado por canais de água, denominados aquaporinas (AQPs), sendo que a AQP4 é a mais importante no Sistema Nervoso Central, e encontra-se expressa nas terminações dos astrócitos que contactam com os vasos cerebrais. De facto, o edema cerebral ocorre em muitas neuropatologias, e o consumo de MET não é exceção. No entanto, o papel da AQP4 nos efeitos da MET é ainda desconhecido. Além disso, a AQP4 tem duas isoformas, a M1 e a M23, e é a sua proporção que regula a homeostase da água, uma vez que a presença da isoforma M23 estabiliza a função do canal de água enquanto a isoforma M1 causa alterações na função da AQP4. Deste modo, é importante esclarecer o papel da AQP 4 na disfunção da barreira hematoencefálica e na formação do edema cerebral induzidos por MET. A presente tese está dividida em 5 capítulos. No capítulo 1 é apresentada uma revisão da literatura sobre os diversos temas estudados no laboratório e detalhados nos capítulos seguintes. No capítulo 2 investigou-se o efeito da MET na comunicação entre astrócitos e CEs com particular interesse no papel do fator de necrose tumoral alfa (TNF-α). Depois de mostrar um aumento da libertação de TNF-α induzido por MET, quer pelos astrócitos quer pelas CEs, provou-se que esta citocina pró-inflamatória estava envolvida no aumento da permeabilidade das CEs através da ativação da via de sinalização do fator nuclear kappa B (NF-κB). Estes resultados foram corroborados por estudos em animais onde se observou um aumento da permeabilidade da BHE e dos níveis de TNF-α no estriado de murganho, efeitos estes que foram prevenidos pelo bloqueio da via do NF-κB. Deste modo, conclui-se que a via de sinalização do TNF-α/NF-κB está envolvida na disfunção da BHE induzida por MET. De seguida, no capítulo 3 avaliou-se o impacto direto da MET no sistema da AQP4 e foi possível demonstrar que esta droga de abuso, para além de induzir uma disfunção da BHE, também originou um edema cerebral citotóxico e comportamento do tipo depressivo. Curiosamente, a AQP4 teve um papel predominante nestas alterações já que o seu bloqueio preveniu todos os efeitos observados nos murganhos. In vitro foi também possível comprovar o papel importante da AQP4 via produção de espécies reactivas de oxigénio já que o silenciamento deste canal de água ou a sua inibição farmacológica, bem como a exposição a um antioxidante (vitamina C) preveniram as alterações morfológicas induzidas pela MET nos astrócitos. Em conclusão, a AQP4 foi identificada como um alvo importante para prevenir as alterações neurogliovasculares e comportamento depressivo induzidos por MET. Na sequência dos efeitos negativos da MET observados nos capítulos 2 e 3, colocou-se a hipótese de uma nova abordagem com um produto natural de origem vegetal. Deste modo, no capítulo 4 concluíu-se que o partenolídeo (PTL), um extrato obtido da artemísia dos prados (Tanacetum parthenium), tem um papel anti-inflamatório e preveniu o aumento da permeabilidade da BHE e formação de edema cerebral induzidos por MET. Mais ainda, foi possível demonstrar que o TNF-α, através da ativação do seu recetor TNFR1, estava envolvido no aumento de volume dos astrócitos observado na presença de MET. Assim, este trabalho permitiu concluir que o PTL tem um feito benéfico em condições de neuroinflamação e disfunção neurogliovascular induzidos por MET. Por último, o capítulo 5 inclui uma discussão geral sobre os resultados obtidos nos capítulos anteriores. Em conclusão, esta tese permitiu mostrar que a MET interfere não só com a homeostase da água no cérebro, mas também com a função da BHE, e que estes efeitos podem conduzir a alterações comportamentais. Para além disso, demonstrou-se ainda que a neuroinflamação e o stresse oxidativo estão subjacentes aos efeitos negativos causados pela MET e foram identificadas duas abordagens para prevenir estes efeitos, tais como o bloqueio da AQP4 e o uso do partenolídeo.
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18

Tsai, Ming-Che, and 蔡明哲. "Part IMLC601, a Traditional Chinese Medicine attenuates traumatic brain injury in rats by reducing early microglial expression of tumor necrosis factor-αPart IIHigh-altitude pulmonary edema can be prevented by heat shock protein-70-mediated hyperbaric oxygen preconditioning." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/q4c3vn.

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博士
中山醫學大學
醫學研究所
103
Part I Objective: Traumatic brain injury (TBI) causes increased release of several mediators from injured and dead cells and elicits microglial activation. Activated microglia change morphology, migrate to injury sites, and release tumor necrosis factor-alpha (TNF-α) and others. In this study we used a controlled fluid percussion injury model of TBI in the rat to determine whether immediate treatment with MLC601, a traditional Chinese medicine, would affect microglial activation and improve recovery. MLC was chosen for this study because it is beneficial in treating stroke patients and it has been approved for clinical trials. Methods and Materials: A controlled fluid percussion injury model of TBI in the rat was used to determine early treatment (1 h post-injury) or late treatment (4 days postinjury) with MLC 601, would affect microglial activation and improve recovery. Rats were randomly divided into three groups: Sham operation group, TBI with vehicle group, TBI with MLC601 treatment group. Rats with induced TBI were treated with a single intraperitoneal injection of MLC 601 (4 mg/kg) 1h after injury, and then with one injection per day for 2 days. Acute neurological and motor deficits were assessed in all rats the day before and 4 days after injury. An immunofluorescence microscopy method was used to count the numbers of the cells colocalized with neuron- and apoptosis-specific markers, and the cells colocalized with microglia- and TNF-α-specific markers, in the contused brain regions 4 days post-injury. An immunohistochemistry methods was used to evaluate both the number and the morphological transformation of microglia in the injured areas. Results: It was found that early treatment with MLC 601 had better effects in reducing TBI-induced cerebral contusion than did the late therapy with MLC 601. Cerebral contusion caused by TBI was associated with neurological motor deficits, brain apoptosis, and activated microglia (e.g., microgliosis, amoeboid microglia, and microglial overexpression of TNF-α), which all were significantly attenuated by MLC 601 therapy. Conclusion and Suggestion: These results suggest that early MLC601 therapy may improve outcomes of TBI in rats by attenuating microgliosis, morphological transformation of microglia, and microglial overexpression of TNF-α. Part II Objective:HBO2P (hyperbaric oxygen preconditioning) induces the overexpression of HSP70 (heat-shock protein 70) and attenuates brain edema in rats during simulated high-altitude exposure. However, it is not known whether the increased lung injury scores and the decreased levels of both aquaporin (AQP1) and AQP5 proteins and messenger RNA (mRNA) expression in the lung caused by HAE can be affected by HSP70-mediated HBO2P in rats. In the present study, we hypothesized that HBO2P would protect against HAE-induced acute lung injury and edema via promoting HSP70 in lungs prior to the onset of HAE. Methods and Materials: Rats were randomly divided into four groups: the non-HBO2P+ non-HAE group, the non-HBO2P+HAE group, the HBO2P+HAE group, and the HBO2P+HSP-70 antibodies (Abs)+HAE group. The HBO2P groups were given 100% O2 at 2.0 absolute atmospheres for 1 hour per day for 5 consecutive days. The HAE groups were exposed to simulated HAE (9.7% O2 at 0.47 absolute atmospheres of 6,000 m) in a hypobaric chamber for 3 days, polyclonal rabbit anti-mouse HSP-70-neutralizing Abs were intravenously injected 24 hours before the HAE experiments. Immediately after returning to normal atmosphere, the rats were overdosed with a general anesthetic, and then their bungs were excised en bloc for both histologic and molecular evaluation and analysis. Results: In non-HBO2P+HAE group, the animals displayed higher scores of alveolar edema, neutrophil infiltration, and hemorrhage compared with those of non-HBO2P+non-HAE controls. In contrast, the levels of both aquaporin (AQP) 1 and AQP 5 proteins and mRNA expression in the lung in the non-HBO2P+HAE group were significantly lower than those of non-HBO2P controls. The increased lung injury scores and the decreased levels of both AQP1 and AQP5 proteins and mRNA expression in the lung caused by HAE was significantly reduced by HBO2P+HAE. Furthermore, HSP70 Abs, in addition to reducing lung HSP70 proteins, significantly attenuated the beneficial effects of HBO2P in HAE. Conclusion and Suggestion: Our results suggest that high-altitude lung edema can be prevented by HSP-70-mediated HBO2P in rats.
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19

Bshouty, Zoheir. "Factors affecting pulmonary vascular pressures and edema formation." 1990. http://hdl.handle.net/1993/17036.

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20

Křížová, Libuše. "Výzkum sklivce a vitreoretinálního rozhraní u mikrovaskulárních chorob sítnice se zaměřením na oční komplikace diabetes mellitus." Doctoral thesis, 2016. http://www.nusl.cz/ntk/nusl-347500.

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In this work I present conclusions of clinical-laboratory research focused on the patients with diabetic macular edema (DME). We performed biochemical and immunochemical analyses of vitreous samples that were collected during the pars plana vitrectomy. Moreover, at patients with non-proliferative diabetic retinopathy (NPDR) we assessed morphological characteristics of DME using optical coherence tomography (OCT). According to our findings, the vitreous and serum concentrations of uric acid and glucose were significantly higher in patients with diabetic retinopathy and DME compared to controls. Also total ratio (serum/ vitreous concentration) of uric acid and glucose was in diabetics significantly higher than in controls. The most important determinant of increasing concentration of both uric acid and glucose in the vitreous was the grade of diabetic retinopathy. Moreover, we demonstrated significant correlation between vitreous concentration of uric acid and concentration of the vascular endothelial growth factor (VEGF) in patients with DME and NPDR. We found further, that the volume of the macula (cube volume - CV) computed with the software of Cirrus HD-OCT correlates in diabetics significantly with the vitreous VEGF concentration, but not with uric acid. This OCT parameter could be used to...
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DULEBO, Alexander. "Mechanizmy podílející se na aktivaci sodíkového transportu TIP peptidem odvozeným z faktoru nádorové nekrózy." Doctoral thesis, 2012. http://www.nusl.cz/ntk/nusl-85701.

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The Tumor Necrosis Factor derived-TIP peptide is a small 17 amino acids cyclic peptide with lectin-like activity, that possesses several therapeutically relevant biological activities, among which is activation of alveolar liquid clearance in both healthy and injured lungs in vivo. Accumulation of fluid in the lungs? alveoli and interstitial spaces is a life-threatening condition called pulmonary edema. The mortality rate due permeability pulmonary edema, accompanied by a dysfunction of the alveolar/capillary barrier, is high because no effective treatment lacking side effects exists nowadays. It is known that the TIP peptide is able to activate vectorial Na+ transport ? which mediates lung liquid clearance. However, the mechanism of action of remains elusive. The aim of this thesis was to investigate the initial steps of interaction between the TIP peptide and airway epithelial cells. Numerous novel methods and single-molecule techniques were used to unravel: (i) how the TIP peptide interacts with the molecules on the apical side of the lung epithelial cells; (ii) whether the TIP peptide need to be internalized inside of the cells to trigger its effects; (iii) the nature of the interaction between the TIP peptide and its putative receptor(s); (iv) the putative receptor(s) for the TIP peptide on the apical surface of the lung epithelial cells.
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