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Emprego de membrana de celulose microfibrilar na ceratoplastia lamelar em coelhos (O. cuniculus, Linnaeus, 1758) : aspectos clínicos, morfológicos e imunoistoquimicos /Macedo, Luciana Ricciardi. January 2008 (has links)
Orientador: José Luiz Laus / Banca: Auero Evangelista Santana / Banca: Thiago Luiz de Salles Gomes / Resumo: Avaliaram-se descritivamente, à clínica, à histopatologia e à imunoistoquímica (ki 67- marcador de proliferação celular) os resultados, da cicatrização da córnea, após ceratoplastias lamelares com membrana de celulose microfibrilar em coelhos. Para tal, utilizaram-se 30 coelhos , distribuídos em 5 grupos de 6 animais, avaliados por até 60 dias de pós operatório. A avaliação clínica revelou manifestações moderadas de edema, blefaroespasmos, fotofobia desde o segundo dia, evoluindo para formas discretas ou ausentes a partir do sétimo dia, onde observou-se clinicamente o reparo do defeito da córnea. A histopatologia revelou uma fina camada de células escamosas, recobrindo totalmente a área lesada, aos sete dias, e com leve infiltrado de células polimorfonucleares. Observou-se a presença de vasos no epitélio a partir do 15º dia , com regressão aos 48º dias .A imunoistoquímica mostrou aumento de células em proliferação aos 15 dias no epitélio (p= 0,049) e aos trinta dias no estroma (p= 0,042). Frente aos resultados obtidos, há como admitir que mesmo com o defeito corneal concluído, aos sete dias, o sistema de defesa celular ainda se manteve ativo, pois a proliferação celular no epitélio se mostrou mais intensa aos 15 dias de observação ,conforme demonstrado imunoistoquimicamente. Onde nesse período ocorreu remodelamento e adesão epitelial da córnea, características satisfatórias em ceratoplastia lamelar em coelhos . / Abstract: Were evaluated the clinic, the histopathology and immunohistochemistry (ki 67 - marker of cell proliferation), the results of the membrane of cellulose in lamellar keratoplasty in rabbits. To this end, 30 rabbits were used, divided into 5 groups of 6 animals, assessed by up to 60 days of post-operative. The assessment showed clinical manifestations of moderate swelling, blefarospasmos, photophobia since the second day, evolving into discrete forms or absent from the seventh day, where there was clinically repair the defect of the cornea. The histopathology revealed a thin layer of squamous cells, completely covering the injured area, the seven days, and with mild infiltration of polymorphonuclear cells. There was the presence of vessels in the epithelium from the 15 th day, with regression of days to 48. Immunohistochemistry showed increased cell proliferation in the 15 days in the epithelium (p = 0049) and the thirty days in the stroma (p = 0042) . Facing the results achieved, as there admit that even with the beginning of healing, and with the defect of the cornea closed to seven days, the system of defence cell remained active, as in the epithelial cell proliferation was more intense at 15 days, as shown imunoistochemistry. Where in that period showed epithelial remodeling and membership, characteristics satisfactory in lamellar keratoplasty in rabbits. / Mestre
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The Effects of Parkinson's on Fixational StabilityMallahan, Erin L. 01 January 2005 (has links)
Parkinson's disease (PD) is a progressive, neurological movement disorder. The stability of eye movements in PD is not well understood but many patients report difficulty doing tasks that require stabilized fixation and gaze. The ability to stabilize an image on the retina is critical is acquiring visual information. The purpose of this study was to compare the stability of fixational eye movements of PD patients to those of age-matched controls. Eye movements during simple fixation tasks were recorded from 66 subjects (ages 52 to 84), and 36 age-matched controls (ages 58-85). The absolute velocity of the fixational eye movements were recorded and correlated to a clinical measure of disease progression as measured by the Unified Parkinson's Disease Rating Scale (UPDRS). Unstable, non-rhythmic eye movements were seen in the PD patients. There were significant differences in the absolute velocity and standard deviation between the control group and the PD group in both the horizontal and vertical directions. The correlation of the absolute velocity to the UPDRS was not significant. Parkinson's disease does appear to affect the stability of eye movements. The instabilities in the eye movements appear to precede body tremor. This could lead to an early method for diagnosis and analysis of the disease.
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Etude de la transparence de greffons cornéens humains : imagerie OCT, analyse par diffusion et modélisation électromagnétique / Study of transparency loss in human corneal grafts : OCT, light scattering measurement and electromagnetic modellingCasadessus, Olivier 07 December 2012 (has links)
Prolongement central de la sclère, la cornée est la couche la plus externe de l'œil. Elle laisser pénétrer la lumière dans le globe oculaire grâce à sa propriété de transparence. Cette transparence repose sur une structure très organisée du tissu, maintenue en équilibre physiologique. Lorsque cet équilibre est rompu, notamment suite à une augmentation anormale de son taux d'hydratation et au développement d'un œdème, l'épaisseur du tissu augmente et il tend à s'opacifier. Lorsque l'œdème devient trop important, il est nécessaire de procéder à une greffe. Les cornées destinées à la greffe sont triées dans des banques de tissus, et sont en particulier soumises à une évaluation qualitative de leur transparence. Cette thèse s'inscrit dans le cadre d'un projet visant à étudier les propriétés de diffusion de greffons cornéens humains, afin d'améliorer l'évaluation quantitative de leur transparence en banque des tissus ou de mieux paramétrer les lasers de découpe lors des greffes de cornées, dont les performances sont altérées à cause du phénomène de diffusion. Le comportement diffusant de la cornée est mesuré dans l'espace réfléchi, afin d'évaluer à terme la possibilité d'une caractérisation in vivo. Conjointement à la mesure de diffusion, une imagerie du volume de la cornée est réalisée grâce à un dispositif de tomographie de cohérence optique apportant une caractérisation de la structure microscopique du tissu. L'œdème et son développement sont ainsi caractérisés par l'analyse de la diffusion du tissu, de sa transparence et des hétérogénéités à l'échelle du micron. / Along with the crystalline lens, the cornea is the unique tissue being transparent in the human body. With a transmission coefficient over 90% in the visible spectrum, the main function of the cornea is to transmit the light inside the eye. This property is due to an absence of blood vessels and a very regular organization of the corneal bulk. In the case of an edema development, the cornea swells because of an abnormally high hydration. This involves a disorganization of its internal structure and an increase of the light scattering, leading to cornea haziness. When the edema is too critical, a graft is then required. In tissue banks, several criteria, such as the evaluation of the transparency, are considered in order to choose only the tissues eligible for corneal transplantation. This thesis aims to study the scattering properties of human corneal grafts in order to improve transparency evaluation in tissue banks or to lead to a better calibration of laser cuts during surgery procedure. A characterization of the scattering properties of the tissues is performed in the reflective half-space. Indeed, backscattering characterization could be used in in-situ conditions. Moreover, 3D images of the bulk of the cornea are performed using a Optical Coherence Tomography set-up. Edema developement is studied through the analysis of the scattering behaviour and of the microscopic structure of the graft. Scattering properties and microstructure are linked together through the use of an electromagnetic modelling. Maxwell's equations are solved using Born approximation, and a numerical method was adapted to perform those calculations in the case of the cornea.
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Avaliação do potencial da associação de dendrímeros e iontoforese para a administração ocular de fármacos / Evaluation of the combination of dendrimers and iontophoresis for ocular drug administrationSouza, Joel Gonçalves de 22 September 2014 (has links)
A administração tópica de colírios é a maneira mais conveniente de se tratar doenças oculares. O grande desafio para a tecnologia farmacêutica é garantir que o fármaco administrado nessa forma farmacêutica chegue ao local de ação em concentrações adequadas, com efeitos adversos reduzidos, tempo de ação prolongado e dose única. Para tanto, o desenvolvimento de sistemas de liberação e de estratégias adequadas de administração tornam-se necessários. Assim, o objetivo deste trabalho foi avaliar a influência da iontoforese na penetração ocular de dendrímeros de poliamidoamina (PAMAM) de geração 4, com diferentes grupos superficiais (PAMAM G4, catiônico e PAMAM G3.5, aniônico), preparar complexos desses dendrímeros com um anti-inflamatório modelo, a dexametasona (Dexa), e avaliar a influência da associação de dendrímeros e iontoforese na penetração corneal da Dexa em modelos ex vivo e in vivo. Complexos Dexa-PAMAM foram obtidos e caracterizados por espectroscopia de infravermelho e ressonância magnética nuclear (H1-RMN, 13C-RMN e DOSY), espalhamento dinâmico de luz e espectroscopia UV/vis para avaliar a formação dos complexos, seu tamanho e potencial zeta, além de alterações na solubilidade da Dexa. A velocidade de liberação da Dexa dos complexos foi verificada por estudos de liberação in vitro utilizando membrana sintética. A penetração e distribuição dos PAMAMs na córnea e sua influência na penetração da Dexa foi avaliada ex vivo utilizando córnea de porco, microscopia confocal de varredura a laser (MCVL) e cromatografia de ultra performance aliada a um detector de massas para quantificação do fármaco permeado. A citotoxicidade dos PAMAMs foi avaliada em cultura de células epiteliais da retina e células epiteliais da córnea. Por fim, verificou-se in vivo a influência da iontoforese e dos PAMAMs sobre a quantidade de Dexa no humor aquoso de olhos de coelhos. Os estudos de caracterização indicaram que a Dexa foi incorporada aos PAMAMs e que esses complexos apresentaram cerca de 50 nm de tamanho médio pela técnica de NTA, com a presença de partículas pequenas e agregadas quando dispersos em meio fisiológico e potencial zeta de + 6,4 mV e -18,5 mV para Dexa-PAMAM G4 e Dexa-PAMAM G3.5, respectivamente. A solubilidade aparente da Dexa aumentou 3,9 e 10,3 vezes nos complexos com PAMAM G4 e PAMAM G3.5, respectivamente. O PAMAM G3.5 e PAMAM G4 diminuiram 82 e 1,7 vezes, respectivamente, o coeficiente de difusão da Dexa. Os estudos ex vivo indicaram que a iontoforese foi capaz de direcionar os dendrímeros para dentro da córnea, além de aumentar 2,9, 5,6 e 3,0 vezes a quantidade de Dexa permeada a partir das formulações que continham Dexa livre, Dexa-PAMAM G4 e Dexa-PAMAM G3.5, respectivamente. Aumentou também a quantidade de Dexa retida na córnea em aproximadamente 2 vezes para todas as formulações. Os experimentos de citotoxicidade evidenciaram a maior toxicidade do PAMAM G4 e sua dependência da concentração e tempo de incubação. Por fim, os experimentos in vivo mostraram que a iontoforese aumentou a concentração de Dexa no humor aquoso cerca de 2, 2,5 e 6,6 para a Dexa livre, Dexa-PAMAM G4 e Dexa-PAMAM G3.5, respectivamente. Portanto, a associação de dendrímeros PAMAM com a iontoforese representa uma estratégia promissora para a administração tópica direcionada e sustentada de fármacos na córnea. / Topical administration of eye drops is the most convenient way for treatment of eye diseases. The challenge for the pharmaceutical technology is to ensure that the drug administered in the eye drops reaches the site of action in appropriate concentrations with reduced side effects, prolonged effect and single dose. Therefore, the development of drug delivery systems and appropriate strategies become necessary. The objective of this work was to evaluate the influence of iontophoresis in the ocular penetration of generation 4 polyamidoamine dendrimers (PAMAM) with different surface groups (PAMAM G4, cationic, and PAMAM G3.5, anionic), prepare complexes of these dendrimers with an anti-inflammatory drug model, dexamethasone (Dexa), and evaluate the influence of dendrimers and iontophoresis association on Dexa cornea penetration using ex vivo and in vivo models. Dexa-PAMAM complexes were obtained and characterized by infrared spectroscopy, nuclear magnetic resonance (H1-NMR, 13C-NMR and DOSY), dynamic light scattering and UV/VIS spectroscopy to evaluate the formation of the complexes, their size and zeta potential, as well as changes in drug solubility. Dexa release rate from complexes was determined from the in vitro release studies using synthetic membrane. The penetration and distribution of PAMAMs into the cornea and their influence in the ex vivo Dexa penetration was assessed using pig\'s cornea, confocal scanning laser microscopy (CSLM) and ultra performance chromatography coupled to a mass spectrometer for quantification of the drug permeated. PAMAMs cytotoxicity was assessed in culture of retina epithelial cells and cornea epithelial cells. Finally, the influence of iontophoresis and PAMAMs on Dexa concentration in the aqueous humor of rabbit eyes was evaluated in vivo. The characterization results showed that Dexa was incorporated to PAMAMs and that these complexes had an average size of approximately 50 nm using the NTA technique, with the distribution of small particles and aggregates when dispersed in physiological medium. The zeta potential of Dexa-PAMAM G4 and Dexa PAMAM G3.5 complexes were +6.4 mV and -18.5 mV, respectively. PAMAM G4 and G3.5 PAMAM enhanced Dexa solubility by 3.9 and 10.3-fold, respectively. PAMAM G3.5 and PAMAM G4 decreased by 82 and 1.7-fold Dexa diffusion coefficient. The ex vivo studies indicated that iontophoresis directed dendrimers into the cornea, increasing the amount of Dexa permeated by 2.9, 5.6 and 3.0-fold for the formulations containing free Dexa, Dexa-PAMAM G4 and Dexa-PAMAM G3.5, respectively. Iontophoresis also increased approximately 2-fold the amount of drug retained into the cornea for all formulations. The cytotoxicity experiments revealed that PAMAM G4 toxicity was dependent on the concentration and incubation time. Finally, the in vivo experiments showed that iontophoresis increased Dexa concentration in the aqueous humor by 2, 2.5 and 6.6-fold for free Dexa, Dexa-PAMAM G4 and Dexa-PAMAM-G3.5, respectively. Therefore, the combination of iontophoresis with PAMAM dendrimers represents a promising strategy for targeted and sustained topical drug delivery to the cornea.
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Efeito do S-nitroso-N-acetilpenicilamina sobre receptores vaniloide de potencial transitório 1 em córnea de camundongos / Effect of S-nitroso-N-acetylpenicillamine on transient receptors potencial vanilloid type 1 in córnea of miceLarissa Domenegueti Ferreira 10 June 2016 (has links)
Introdução: Receptores TRPV1 são canais catiônicos nociceptivos não seletivos. Eles desempenham um papel na sensação de dor na córnea. No presente trabalho, descreveremos a resposta do TRPV1 na córnea de camundongos e TRPV1 -/- a estímulos químicos e o efeito do SNAP sobre este receptor. Métodos: camundongos C57BL/6 e TRPV1 -/- foram comparados. As observações incluíram o influxo de cálcio na cultura, observação direta e o comportamento de limpeza do olho após o desafio na córnea com 1µM da capsaicina (CAP) com ou sem 1mM do colírio SNAP. Resultados: As características da superfície ocular não eram diferentes entre ambos os genótipos, exceto que a sensibilidade para CAP é inferior em TRPV1 -/- (p = 0,0019 e 0,0095, respectivamente). A imunocoloração revelou que TRPV1 é expresso na camada basal do epitélio da córnea, apenas nos camundongos C57BL/6. CAP estimula o influxo de cálcio em cultura de células epiteliais e a sensibilidade corneana em C57BL/6 in vivo foi reduzida na presença do SNAP (p = 0,0329 e 0,01, respectivamente). Conclusão: A ausência dos receptores TRPV1 no epitélio da córnea não afeta o fenótipo da superfície ocular de camundongos. A resposta para tirar colírios revelou que ela poderia funcionar como uma terapia analgésica devido ao seu antagonismo com o TRPV1. / TRPV-1 receptors are non-selective nocioceptive cation channels. They play a role in cornea sensation. In the present work we describe the response of corneas of TRPV1-/- and mice to chemical stimuli and the effect of SNAP on this receptor. TRPV1-/- and C57BL/6 mice were compared. The observations included the calcium influx in culture, direct observation and the behavior of eye wipe after corneal challenge with 1?M Capsaicin (CAP) with or not 1mM SNAP eye drops. Ocular surface characteristics were not different between both genotypes, except that the sensitivity to CAP is lower in TRPV1-/- (p=0.0019 and 0.0095, respectively). Immunostaining revealed that TRPV 1 is expressed in the basal layer of the cornea epithelia, only in the C57 mice. CAP stimulated calcium influx in epithelial cells in culture and cornea sensitivity in C57 mice in vivo was reduced in the presence of SNAP (p=0.0329 and 0.01, respectively). The absence of TRPV-1 receptors in the cornea epithelia did not affect the ocular surface phenotype in mice. The response to SNAP eye drops revealed that it could work as an analgesic therapy due to its antagonism to the TRPV1.
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Características clínicas e imunológicas de pacientes com ceratocone e alergia ocular: um estudo transversal com ênfase na análise da inflamação da superfície ocular / Clinical and immunological characteristics of patients with keratoconus and ocular allergy: a cross sectional study with emphasis on the analysis of ocular surface inflammationSandrin, Leda das Neves Almeida 15 December 2016 (has links)
Objetivo: Comparar as características inflamatórias da superfície ocular de pacientes com ceratocone (CE) às de pacientes com alergia ocular (AO). Métodos: Realizou-se um estudo transversal, envolvendo 134 participantes, divididos em três grupos: alergia ocular (AO)(n=55), ceratocone com ou sem alergia ocular associada (CE) (n=61) e controle (CO) (n=18). Os participantes do estudo foram recrutados e avaliados em clínica privada na cidade de Chapecó-SC, no período de polinização, em dezembro de 2013 e de outubro de 2014 a janeiro de 2015. Para análise dos grupos, todos os pacientes foram avaliados clinicamente por especialistas em alergia e oftalmologia e submetidos a exame de tomografia de córnea com tecnologia de Scheimpflug (Pentacam HRR), medida da osmolaridade da lágrima por impedanciometria (TearLabR) em ambos os olhos e preenchimento de questionários padronizados para alergia ocular (QA) e para doença de superfície ocular (OSDI). Em 107 de 134 pacientes (CE=50, AO=42, CO=15) foram dosadas as citocinas IL-1beta, IL-2, IL-4, IL-5, IL-6, IL-10, IL-12p70, IL-13, IL-15, IL-31, IL-33, IL-17 A, IL-23, TNF-alfa, TNF-beta e INF-gama na lágrima, por meio de tecnologia multiplex com beads magnéticas. A coleta das amostras de lágrimas (5 microlitros no mínimo) foi realizada por meio de aspiração no menisco lacrimal temporal inferior, com capilares de vidro em um único olho. As amostras foram congeladas imediatamente após coleta e mantidas a -80 oC, até o momento da dosagem e análise em agosto de 2016. Resultados: Constatou-se alta prevalência de alergia no grupo com ceratocone 68,85% (42/61), sendo que 42,62% (26/61) dos pacientes desse grupo apresentaram alergia ocular. A intensidade do prurido ocular foi maior nos pacientes AO e no grupo CE, do que no grupo controle (p < 0,001 e p=0,047) e maior no grupo AO do que no CE (p < 0,001). As citocinas INF-gama, IL-13, IL-15, IL-17A, IL-1beta, IL-2, IL-4, IL-5, IL-31, TNF-beta foram estatisticamente mais elevadas no grupo AO, quando comparadas ao grupo CE. No grupo controle, houve correlação direta da diferença absoluta da osmolaridade (delta osmol) com o nível encontrado para todas as citocinas dosadas. Observou-se, ainda, correlação direta entre níveis de IL-1beta, IL-6 e TNF-alfa com OSDI (p=0,044, p=0,010 e p=0,047) no grupo CE. A osmolaridade foi maior no grupo CE, quando comparado ao AO (p=0,043). Conclusões: Pacientes com ceratocone apresentaram alterações inflamatórias na superfície ocular, tais como: correlação direta do índice OSDI com IL-1beta, IL-6 e TNF-alfa na lágrima; intensidade de prurido mais elevada que no grupo controle e osmolaridade maior que no grupo com AO. No grupo AO, observou-se índices OSDI maiores que no grupo controle e aumento de várias citocinas dosadas, quando comparadas ao grupo CE. Nos pacientes controle, a instabilidade no filme lacrimal (delta osmol), correlacionou-se diretamente com a inflamação ocular (citocinas dosadas). Observou-se alta prevalência de formas leves de alergia ocular no grupo CE (40,98%) e apenas um caso de alergia ocular grave (ceratoconjuntivite atópica [1,3%]), esses dados estão em desacordo com a maior parte da literatura disponível sobre o assunto. Em conjunto, os achados do presente estudo podem estar relacionados a características específicas da região estudada / Purpose: To compare the inflammatory profile of the ocular surface of patients with keratoconus with that of patients with ocular allergy. Methods: A cross sectional study was carried out and involved 134 participants, divided into three groups: ocular allergy group (OA) (N=55), keratoconus with or without ocular allergy (KC) (N=61) and a control group (CO) (N=18). The study participants were recruited and evaluated in a private clinic in the city of Chapecó-SC, during the pollination period in 2013 (December) and from 2014 to 2015 (October to January). In order to analyze the three groups, all patients were evaluated clinically by allergy and ophthalmology specialists, submitted to a corneal tomography exam with Scheimpflug technology (Pentacam HRR), to impedanciociometry to assess tear osmolarity (Tear LabR) of both eyes and to standardized questionnaire rates for ocular allergy (AQ) and for ocular surface disease index (OSDI). Cytokines (IL-1beta, IL-2, IL-4, IL-5, IL-6, IL-10, IL-12p70, IL-13, IL-15, IL-31, IL-33, IL-17 A, IL-23, TNF-alfa, TNF-beta and INF-gama) levels were assessed in 107 out of 134 patients using multiplex technology with magnetic beads. Tear collection of at least 5 microliters was carried out on a single eye by suction in the inferior temporal lacrimal meniscus with glass capillaries. The samples were frozen at -800C, immediately after collection to the time of dosing and analysis in August 2016. Results: The prevalence of allergy in the keratoconus group was 68.85% (42/61), within the same group 42.62% (26/61) of the patients had ocular allergy. Ocular pruritus intensity was higher in the OA group and in the KC group than in the control group (p < 0,001 e p=0,047), and higher in the OA group than in the KC group (p < 0,001). Cytokines INF-gama, IL-13, IL-15, IL-17A, IL-1beta, IL-2, IL-4, IL-5, IL-31, TNF-beta were statiscally higher in the OA group in comparision to the KC group. In the control group, there was a positive correlation of the difference measurement of osmolarity (osmol delta) between the eyes with all cytokines dosed. In the KC group, IL-1beta, IL-6 e TNF-alfa correlated positively with OSDI (p=0,044, p=0,010 e p=0,047). Tear osmolarity was higher in the KC group than in the OA group (p=0,043). Conclusions: Patients with keratoconus had inflammatory changes in the ocular surface, such as: direct correlation between OSDI and tear IL-1beta, IL-6 and TNF-alpha levels; higher pruritus intensity than the control group and higher osmolarity than the OA group. In the OA group, OSDI levels were higher than in the control group and some cytokines had higher levels than the KC group. In the control patients, tear film instability (delta osmol) was direct correlated to ocular inflammation (dosed cytokines). In the KC group, there was a high prevalence of mild forms of ocular allergy (40.98%) and only one case of severe ocular allergy (atopic keratoconjunctivitis [1.3%]). However, most studies avaiable have associated keratoconus with severe forms of ocular allergy. Together, these findings may be related to specific characteristics of the region of study
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Avaliação do endotélio da córnea de coelhos (oryctolagus cuniculus) em diferentes faixas etárias utilizando a microscopia especularBrambatti, Gustavo January 2013 (has links)
O endotélio é uma monocamada de células achatadas, poligonais e interligadas que recobrem a superfície posterior da córnea, sendo fundamental na manutenção da transparência desta estrutura. Apesar dos coelhos (Orictolagus cuniculus) serem amplamente utilizados em pesquisas oftálmicas, não existem avaliações detalhadas referentes ao endotélio da córnea desta espécie em diferentes idades. Objetivou-se estudar os parâmetros morfológicos e morfométricos do endotélio da córnea de coelhos de diferentes idades, utilizando-se a microscopia especular. Foram estudados 36 bulbos oculares de 18 coelhos, machos ou fêmeas, de diferentes faixas etárias divididos em três grupos com seis animais cada, designados por: G I (animais com idade de seis meses); G II (animais com 1 ano de idade) e G III (animais com quatro anos de idade). A densidade celular endotelial média nos animais dos grupos G I, G II e G III foi de respectivamente 2307,16± 319,04, 1894,75 ± 170,81 e 1818,66 ± 245,11 células/mm2. A área celular média foi de respectivamente 364,43 ± 39,36, 374,79 ± 48,46 e de 378.50 ± 02,97 μm2 para G I, G II e G III. O pleomorfismo médio ou porcentagem de células hexagonais no endotélio central do olho direito e esquerdo de coelhos foi respectivamente de 65,40 ± 23,39% e de 75,15 ± 10,44%, com variação de 42,01 a 88,80% e de 60,71 a 81,60%. Os resultados apontam decréscimo da densidade, do pleomorfismo, e aumento da área celular média com o aumento da idade. O endotélio da córnea de coelhos sofre alterações decorrentes do avanço da idade. / The corneal endothelium is a monolayer of interconnected flattened polygonal cells that cover the back surface of the cornea, it is essential for the maintenance of its transparency. Due to the complete lack of data on the endothelial cells of rabbits (Orictolagus cuniculus) it`s ophthalmic widely used in research, no data relating to corneal endothelium in this species correlating their age. Therefore aimed to assess cell density, the average cell area and morphology of the corneal endothelium of rabbits at different ages. It was studied 36 eyes of 18 rabbits, male or female, of different ages. Rabbits were divided into three groups with 6 animals each, designated by: G I (animals aged six months), G II (animals with 1 year) and G III (animals with four years of age). The mean endothelial cell density in the animals of G I, G II and G III were respectively 2307,16± 319,04, 1894,75 ± 170,81 e 1818,66 ± 245,11 células/mm2. The average cell area was respectively 364,43 ± 39,36, 374,79 ± 48,46 e de 378.50 ± 02,97 μm2 for GI, G II and G III. The pleomorphism medium or percentage of hexagonal cells in the endothelium of the central right and left eyes of rabbits was respectively 65.40 ± 23.39% and 75.15 ± 10.44%, ranging from 42.01 to 88.80 %, and 60.71 to 81.60%. The results indicate a decrease in density, pleomorphism, and increased in average cell area with increasing age. The corneal endothelium of rabbits changes with advancing age.
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Estudo sobre a deformação da córnea utilizando o sistema de tonometria de não contato integrado a uma câmera de Scheimpflug em olhos saudáveis / Evaluation of corneal deformation analyzed with non-contact tonometer system integrated with an ultra-high-speed (UHS) Scheimpflug camera in healthy eyesValbon, Bruno de Freitas 23 September 2016 (has links)
OBJETIVOS: 1) Avaliar os parâmetros de biomecânica ocular provenientes do Corvis ST (Oculus Corvis ST, Scheimpflug Technology; Wetzlar, Germany) obtidos de olhos saudáveis de uma população de pacientes brasileiros. 2) Correlacionar os parâmetros derivados do Corvis ST com a idade de pacientes jovens saudáveis. 3) Verificar se as técnicas de facoemulsificação (FC) e do laser de femtosegundo (LFS), empregadas na correção cirúrgica de catatara, influenciam os parâmetros de biomecânica ocular provenientes do Corvis ST. 4) Analisar as alterações da deformação da córnea observadas em um caso de ectasia pós LASIK com flap espesso. MÉTODOS: 1) Estudo clínico transversal conduzido em 90 pacientes (90 olhos saudáveis). Foram avaliados 11 parâmetros derivados do sistema de tonometria de não contato integrado com a câmera ultrarrápida de Scheimpflug (Oculus Corvis ST, Scheimpflug Technology; Wetzlar, Germany), a saber: deformidade de amplitude (DA); pressão intraocular; 1st A time; tempo de concavidade máxima; 2nd A time; 1st A Length (tempo da primeira aplanação); 2nd A Length (tempo da segunda aplanação); raio de curvatura de maior alcance; raio de curvatura normal; velocidade de entrada (Vin) e de saída (Vout). Estes parâmetros foram correlacionados com a espessura central corneana mensurada pela Tomografia de Córnea e Segmento Anterior (Pentacam® - Oculus, Wetzlar, Germany). 2) Estudo clínico observacional, retrospectivo, conduzido em 89 pacientes (89 olhos saudáveis). Os parâmetros derivados do Corvis ST foram correlacionados com a idade dos pacientes. 3) Estudo clínico prospectivo, envolvendo 151 olhos de 127 pacientes com diagnóstico de catarata nuclear. Setenta e cinco olhos de 65 pacientes foram submetidos à técnica do laser de femtosegundo (AlconLenSx, Aliso Viejo, USA) e 76 olhos de 62 pacientes à facoemulsificação convencional (Alcon Infinit, Fort Worth, USA). Foram avaliados os 11 parâmetros de biomecânica ocular derivados do Corvis ST antes (Pré) e após as cirurgias de catarata (D1, primeiro dia de pósoperatório). A densitometria do cristalino (scattering) foi realizada pelo PNS (Pentacam Nucleus Staging). 4) Avaliação com tomografia de coerência óptica de espessura dos flaps corneanos pós Lasik e análise dos parâmetros biomecânicos provenientes do Corvis ST em uma córnea com ectasia pós Lasik. RESULTADOS: 1) A média de idade dos pacientes foi de 35,80 ± 12,83 anos. A média do equivalente esférico foi de -3,29 ± 3,69 dioptrias. A média da espessura central corneana foi de 547,50 ± 32,00 ?m Os valores dos 11 parâmetros biomecânicos obtidos de olhos saudáveis, foram os seguintes: deformidade de amplitude 1,05 ± 0,08 mm; tempo de concavidade máxima 18,38 ± 0,93 ms; pressão intraocular 16,43 ± 2,15 mmHg; tempo da primeira aplanação (1st A time) 8,32 ± 0,33 ms; tempo da segunda aplanação 23,80 ± 0,44 ms; raio de curvatura de maior alcance 11,09 ± 2,06 mm; raio de curvatura normal 7,59 ± 0,67 mm; tempo da primeira aplanação (1st A Length) 2,07 ± 0,38 mm; tempo da segunda aplanação (2nd A Length) 2,37 ± 0,47 mm; velocidade de entrada (Vin) 0,21 ± 0,05 m/s e velocidade de saída (Vout) -0,33 ± 0,07 m/s. 2) A média de idade dos pacientes foi de 27,50 ± 6,30 anos. O tempo de concavidade máxima alcançada da córnea (HC-time) foi o único dos 11 parâmetros que apresentou correlação significativa com a idade (p=0,04, rs=0,18). 3) A média de idade dos pacientes dos grupos LFS (laser de femtosegundo) e FC (facoemulsificação convencional) foram, respectivamente, 67,6 ± 9,9 anos e 68,4 ± 11,8 anos. No grupo LFS, 9 dos 11 parâmetros foram estatisticamente significativos entre o Pré e D1; e no grupo FC, 7 dos 11 parâmetros foram estatisticamente significativos entre o Pré e D1. Entre os 11 parâmetros biomecânicos avaliados, somente o tempo de concavidade máxima da córnea (HC-time) foi significativamente diferente entre os dois grupos em D1 (p=0,0387). 4) Paciente do sexo feminino, 45 anos, submetida à Lasik em ambos os olhos. Com a utilização da tomografia de coerência óptica (OCT Rtvue, OptoVue, Fremont, CA,USA) foram identificados: um flap com espessura central de 392 ?m no OD e dois cortes, sendo um flap incompleto profundo e o outro mais fino superiormente, no OE. Os parâmetros derivados do Corvis ST como a deformidade de amplitude são diferentes em ambos os olhos. CONCLUSÕES: 1) Os valores de 8 dos 11 parâmetros derivados do Corvis ST foram influenciados pela espessura central da córnea, porém esta influência foi baixa. 2) Em olhos saudáveis de pacientes jovens foi obtida correlação significativa entre a idade e o tempo de concavidade máxima, que é o tempo do início de aplanação até a concavidade máxima alcançada da córnea. 3) O laser de femtosegundo para cirurgia de catarata e a técnica de facoemulsificação convencional induziram alterações nas propriedades biomecânicas da córnea no D1. Dos 11 parâmetros biomecânicos estudados apenas o tempo de concavidade máxima da córnea apresentou diferença significativa entre os grupos (LFS e FC) no D1. 4) A ectasia unilateral após LASIK pode ocorrer devido a flap espesso com falência biomecânica da córnea / PURPOSE: 1) To evaluate ocular biomechanical metrics given by the CorVis ST (Oculus, Inc., Berlin, Germany) in a population of healthy Brazilian patients. 2) To correlate parameters derived from corneal deformation resulting from non-contact tonometry integrated with an ultra-high-speed (UHS) Scheimpflug camera (Oculus Corvis ST, Scheimpflug Technology; Wetzlar, Germany) with age in normal eyes from young patients. 3) To evaluate the changes of corneal biomechanical after femtosecond laser - assisted cataract (FS) and to compare the parameters derived by Corvis ST between standard phacoemulsification (SP) and femtosecond laser - assisted in cataract surgery. 4) To report a case of post-LASIK corneal ectasia due to a thick flap, while the contralateral eye did not develop ectasia after an incomplete deep flap cut, followed by a thinner flap Lasik procedure. METHODS: 1) An observational and cross-sectional study involving 1 eye randomly selected from 90 healthy patients. Studied parameters (including deformation amplitude, first applanation time, highest concavity time, second applanation time, first applanation length, second applanation length, curvature radius highest concavity, curvature radius normal, velocity in, and velocity out) derived from the CorVis ST were correlated to central corneal thickness from the Pentacam (Oculus, Inc.). Differences between data on the basis of gender were evaluated. 2) Observational, retrospective study involving one eye randomly selected from study participants, totaling 89 healthy eyes. The Scheimpflug images were taken with an ultra-high-speed camera during each measurement by the Corvis ST. The deformation amplitude (DA) and other parameters (e.g., pachy apex, intraocular pressure, 1st A time, highest concavity-time, 2nd A time, 1st A Length, 2nd A Length, Wing-Dist, curvature radius highest concavity, curvature radius normal, Vin, Vout) measured by the corvis ST were correlated with age. 3) Prospective study: 151 eyes of 127 patients were underwent cataract surgery. 75 eyes of 65 patients were with femtosecond laser-assisted (FS)(Alcon Len Sx, Aliso Viejo,USA) and 76 eyes of 62 patients with standard phacoemulsification (SP) (Alcon Infinit, FortWorth, USA). 4) Case Report. RESULTS: 1) About the first study: Mean patient age was 35.80 ± 12.83 years (range: 21.07 to 78.84 years). Mean central corneal thickness was 547.50 ± 32.00 ?m (range: 490 to 647 ?m) and mean spherical equivalent refraction was -3.29 ± 3.69 diopters (range: -9.50 to +10.37 diopters). Mean deformation amplitude was 1.05 ± 0.08 mm (range: 0.91 to 1.26 mm). Highest concavity time was 18.38 ± 0.93 ms (range: 16.95 to 21.07 ms). Intraocular pressure was 16.43 ± 2.15 mm Hg (range: 11.50 to 21.0 mm Hg). First applanation time was 8.32 ± 0.33 ms (range: 7.53 to 9.12 ms) and second applanation time was 23.80 ± 0.44 ms (range: 22.76 to 24.95 ms). First applanation length (max) was 2.07 ± 0.38 mm (range: 1.20 to 3.10 mm) and second applanation length (max) was 2.37 ± 0.47 mm (range: 1.33 to 4.12 mm). Curvature radius highest concavity was 11.09 ± 2.06 mm (range: 7.58 to 15.98 mm) and curvature radius normal was 7.59 ± 0.67 mm (range: 6.82 to 11.02 mm). Velocity in was 0.21 ± 0.05 m/s (range: 0.16 to 0.72 m/s) and velocity out was -0.33 ± 0.07 m/s (range: - 0.72 to -0.20 m/s). Studied parameters were not associated with gender. 2) Mean patient age was 27.50 ± 6.30 years. The highest concavity-time was the only studied parameter statistically significantly correlated to age (i.e., p=0.04, rs=0.18). 3) In relation the surgery of cataract: In group of FS, 9 of 11 parameters derived from Corvis ST were statistically significant (ss). In group of SP, 7 of 11 parameters derived from Corvis ST were ss. Only the HC - time was statistically significant between two groups (FS;SP) with p = 0.0387. 4) Corneal OCT identified a deep meniscos-shaped Lasik flap, with a central thickness of a 392 ?m in the right eye, and a incomplete deep peripheral cut in the left eye with a thinner meniscos-shaped LASIK flap. CONCLUSIONS: 1) Eight of 11 ocular biomechanical metrics given by the CorVis ST were associated with central corneal thickness, but the influence of central corneal thickness on these measurements was low. 2) In healthy eyes, age and pressure or biomechanics as derived from the Corvis ST parameters were not associated with exception to highestconcavity-time, i.e., the time from starting until the highest concavity is reached. 3) The use of the femtosecond laser- assisted system for cataract surgery and standard phacoemulsification induzed changes of biomechanical properties of the cornea by Corvis ST. Only 1 of 11 parameters studied was different statistically in two groups. 4) Unilateral ectasia after LASIK may occur due to a thick flap which leads to biomechanical failure of the cornea
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Efeito do S-nitroso-N-acetilpenicilamina sobre receptores vaniloide de potencial transitório 1 em córnea de camundongos / Effect of S-nitroso-N-acetylpenicillamine on transient receptors potencial vanilloid type 1 in córnea of miceFerreira, Larissa Domenegueti 10 June 2016 (has links)
Introdução: Receptores TRPV1 são canais catiônicos nociceptivos não seletivos. Eles desempenham um papel na sensação de dor na córnea. No presente trabalho, descreveremos a resposta do TRPV1 na córnea de camundongos e TRPV1 -/- a estímulos químicos e o efeito do SNAP sobre este receptor. Métodos: camundongos C57BL/6 e TRPV1 -/- foram comparados. As observações incluíram o influxo de cálcio na cultura, observação direta e o comportamento de limpeza do olho após o desafio na córnea com 1µM da capsaicina (CAP) com ou sem 1mM do colírio SNAP. Resultados: As características da superfície ocular não eram diferentes entre ambos os genótipos, exceto que a sensibilidade para CAP é inferior em TRPV1 -/- (p = 0,0019 e 0,0095, respectivamente). A imunocoloração revelou que TRPV1 é expresso na camada basal do epitélio da córnea, apenas nos camundongos C57BL/6. CAP estimula o influxo de cálcio em cultura de células epiteliais e a sensibilidade corneana em C57BL/6 in vivo foi reduzida na presença do SNAP (p = 0,0329 e 0,01, respectivamente). Conclusão: A ausência dos receptores TRPV1 no epitélio da córnea não afeta o fenótipo da superfície ocular de camundongos. A resposta para tirar colírios revelou que ela poderia funcionar como uma terapia analgésica devido ao seu antagonismo com o TRPV1. / TRPV-1 receptors are non-selective nocioceptive cation channels. They play a role in cornea sensation. In the present work we describe the response of corneas of TRPV1-/- and mice to chemical stimuli and the effect of SNAP on this receptor. TRPV1-/- and C57BL/6 mice were compared. The observations included the calcium influx in culture, direct observation and the behavior of eye wipe after corneal challenge with 1?M Capsaicin (CAP) with or not 1mM SNAP eye drops. Ocular surface characteristics were not different between both genotypes, except that the sensitivity to CAP is lower in TRPV1-/- (p=0.0019 and 0.0095, respectively). Immunostaining revealed that TRPV 1 is expressed in the basal layer of the cornea epithelia, only in the C57 mice. CAP stimulated calcium influx in epithelial cells in culture and cornea sensitivity in C57 mice in vivo was reduced in the presence of SNAP (p=0.0329 and 0.01, respectively). The absence of TRPV-1 receptors in the cornea epithelia did not affect the ocular surface phenotype in mice. The response to SNAP eye drops revealed that it could work as an analgesic therapy due to its antagonism to the TRPV1.
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Anatomical and functional analysis of microRNAs in human cornea epithelial progenitor cells. / MicroRNA在人角膜上皮祖細胞的解剖及功能分析 / CUHK electronic theses & dissertations collection / MicroRNA zai ren jiao mo shang pi zu xi bao de jie pou ji gong neng fen xiJanuary 2010 (has links)
By performing microRNA microarrays to globally detect any novel miRNAs in the limbus, eleven microRNAs (hsa-miR-136, hsa-miR-373*, hsa-miR-150, hsa-miR-143, hsa-miR-455, hsa-miR-145, hsa-miR-381, hsa-miR-224, hsa-miR-338, hsa-miR-154, hsa-miR-377) were found to be upregulated while two microRNAs (hsa-miR-122a and hsa-miR-425-3p) were identified as downregulated by more than 2 folds. Among these, hsa-miR-143 and hsa-miR-145 were distingushed to be the most significantly up-regulated limbal miRNAs. Individual assessement of the microarray results of a recently reported stem cell specific microRNA, hsa-miR-21, were also upregulated by more than two thousand fold when comparing limbus and cornea. miR-21, miR-143 and miR-145 were therefore selected as the most likely microRNA candidates in the present study. The expression level of these miRNA candidates were validated and confirmed by quantitative reverse transcription polymerase chain reaction (qRT-PCR). To localize these candidates, we performed in situ hybridization on frozen corneal rim sections using locked nucleic acid (LNA)-modified oligonucleotide probes. Results showed that miR-2I, 143 and 145 were confined in the limbal region with gradation of expression level along the basal-suprabasal line. / Functional roles of these microRNAs were then deciphered by overexpressing human corneal epithelial cell line (HCE) with precursor microRNAs (pre-miRs) through lipophilic transfection. Results showed that high endogenous level of miR-145 could inhibit cell proliferation by 3.5 fold as shown from MTT proliferation assay at day 5, and could generate discrete spherical colonies that resembles the morphology of holoclones at day 8, but not the other two candidate miRNAs. / In conclusion, 1 have identified three novel microRNAs (hsa-miR-21, 143, 145) which were precisely upregulated in the limbus region, while miR-145 was being the most limbal specific. In addition, the functions of miR-145 were found to be inhibitory on cell proliferation, possibly through the indirect regulation of IFNB1. These unprecedented results may suggest a therapeutic potential of miR-145 on limbal stem cell deficiency and limbal tumors because miR-145 can affect cell survival and proliferation. / MicroRNAs is a family of small non-coding RNAs that, in human, binds imperfectly to the 3' untranslated region (UTR) of target mRNAs for translational repression or negative regulation. Recent studies have shown that such negative regulatory pathways may play pivotal roles in the maintenance of asymmetric cell division in embryonic and tissue specific stem cells. Human corneal epithelial progenitor cells (CEPC), a tissue specific stem cell lineage residing between cornea and conjunctiva in the Palisade of Vogt of the limbus region, is known to maintain corneal homeostasis throughout human life. They respond to injury and normal wearing by rapid proliferation and differentiation into transit amplifying cells (TACs) and eventually corneal epithelial cells, though the biological factors controlling this homeostatic switch are still largely unknown. Here I hypothesized that microRNAs can participate in CEPC regulation. Experiments elucidating the anatomical distribution and functional roles of microRNAs on the human cornea rims were performed to testify this proposition. / Protocols aim at enriching the CEPC population were then devised. For the first time a four parameter cell sorting system utilizing ABCG2, Connexin 43, Notch 1 and pyronin Y as markers was established for the prospective in vitro study. Nevertheless, manual microdissection isolating the limbus region and the cornea region was employed for the present study of microRNAs. / This study begins with the phenotypic validation of human cornea rims recruited from the Chinese Hong Kong population using immunohistochemistry. Conventional CEPC markers (p63, EGFR, cytochrome oxidase and cytokeratin 15), embryonic stem cell marker (stat1) and cancer stem cell markers (p73, MDM2 and pStat1) were expressed in the limbus region, suggesting that these specimens contained a source of CEPC for attesting our hypothesis. / To determine the mRNA targets of candidate microRNAs in HCE cells, Whole Human Genome Oligo Microarray Kits (Agilent Technologies) which contained 41K human genes and transcripts were employed. When compared to the scrambled control, HCE cells over-expressed with hsa-miR-21, 143 or 145 revealed differential expression of genes that participate in cell activation, motility and proliferation. Of note, interferon beta 1 fibroblast (IFNB1), a gene that is often deleted or rearranged in cancers, was significantly upregulated by a medium of 1093 fold in pre-miR-145 treated cells as confirmed by real time PCR assays. / Lee, Sharon Ka-wai. / "December 2009." / Advisers: Calvin Chi-Pui Pang; Gary Hin Fai Yam. / Source: Dissertation Abstracts International, Volume: 72-01, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 216-252). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
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