Dissertations / Theses: 'Enucleação ocular de animal'

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Hernandes, Marina Sorrentino. "Geração de espécies reativas de oxigênio e neuroinflamação induzidas por enucleação ocular no sistema visual de ratos." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/42/42137/tde-22072011-143301/.

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O modelo de enucleação ocular em roedores é frequentemente empregado para o estudo dos efeitos da desaferentação de estruturas retinorrecipientes. Avaliamos a geração de espécies reativas de oxigênio (EROs), no colículo superior (CS) e núcleo geniculado lateral dorsal do tálamo (GLD) após enucleação ocular. A oxidação da dihidroetidina revelou o aumento da geração de EROs no CS e no GLD após a lesão. Os resultados de RT-PCR revelaram aumento da expressão gênica de Nox 2 em ambas as estruturas avaliadas. Em contrapartida, observou-se aumento da expressão gênica de Nox 1 e 4 apenas no CS. Com a finalidade de avaliarmos o envolvimento de EROs no remodelamento estrutural após a lesão, animais foram tratados com apocinina e ensaios de imuno-histoquímica foram realizados utilizando-se anticorpos contra neurofilamentos (NFs) e proteínas associadas a microtúbulos-2 (MAP-2). Os resultados revelaram que a enucleação ocular produz um aumento na imunorreatividade para NFs e MAP-2 no CS e GLD, o que foi atenuado pelo tratamento com apocinina.
Unilateral ocular enucleation represents a useful model to study visual system plasticity. We evaluated the reactive oxygen species (ROS) generation in the main visual relays of the mammalian brain, namely the superior colliculus (SC) and the dorsal lateral geniculate nucleus (DLG), after ocular enucleation. Dihydroethidium oxidation revealed increased ROS generation in SC and DLG. ROS generation was decreased by the Nox inhibitors DPI and apocynin. Real-time PCR results revealed that Nox 2 was upregulated in both retinorecipient structures after deafferentation, whereas Nox 1 and Nox 4 were upregulated only in the SC. To evaluate the role of ROS in structural remodeling after the lesions, apocynin was given to enucleated rats and immunohistochemistry was conducted for markers of neuronal remodeling into SC and DLG. Immunohistochemical data showed that ocular enucleation produces an increase of neurofilament and microtubule-associated protein-2 immunostaining in both SC and DLG, which was markedly attenuated by apocynin treatment.

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Santos, Murillo Rezende [UNESP]. "Atividade elétrica dos músculos orbiculares antes e após a instalação de próteses oculares." Universidade Estadual Paulista (UNESP), 2013. http://hdl.handle.net/11449/97365.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
A perda do bulbo ocular compromete não só a estética, mas também a tonicidade muscular da região facial do paciente, uma vez que com a ausência do globo ocular os músculos orbiculares dos olhos podem sofrer atrofia. Desse modo, o objetivo do presente estudo foi verificar a atividade elétrica dos músculos orbiculares, antes e após a instalação de próteses oculares em pacientes que foram submetidos à enucleação unilateral do bulbo ocular. Foram selecionados, por meio de anamnese e exame clínico, 12 pacientes voluntários com indicação de prótese. O sinal eletromiográfico foi realizado com o auxílio do eletromiógrafo, em quatro situações clínicas: Repouso (R), Abertura e Fechamento Normal das Pálpebras (AFN), Abertura e Fechamento Rápido das Pálpebras (AFR) e Apertamento (A). Esses registros foram realizados antes da instalação da prótese ocular, e após 7, 30 e 60 dias da instalação e uso da mesma. Os mesmos ensaios foram realizados no músculo orbicular do olho sadio do paciente, resultados que serviram como controle do estudo. Os dados obtidos foram submetidos à análise estatística pelo programa SPSS (p<0.05) e o t-teste foi utilizado para comparar os músculos superior e inferior por período de tratamento (inicial, 7, 14, 30 e 60 dias), para as quatro condições clínicas. Nas quatro condições clínicas avaliadas foi verificado diferença estatisticamente significativa em relação ao período inicial e após 7 dias da instalação da prótese. O fascículo superior do músculo orbicular do olho apresentou maiores valores de atividade elétrica em relação ao fascículo inferior em todas as situações clínicas avaliadas. Os menores valores de atividade elétrica foram observados durante o período inicial para a condição de repouso (OS 8.418 / OI 5.933) e os maiores após 60 dias na condição...
The eye loss besides affecting patient’s aesthetics, it compromises the muscle tone of the facial region owing to the atrophy of orbicular muscles. Thus, although the use of ocular prosthesis does not return patient’s vision, it fills the anophtalmic cavity restoring the cosmetic and muscle tone. The aim of this present study was to evaluate the electrical activity of orbicular muscles before and after ocular prosthesis insertion of patients who underwent unilateral enucleation of eyeball. The electrical activity of the orbicular muscles was assessed through the Myosystem BR1 electromyograph in four clinical situations: (1) rest, (2) normal opening and closing of the eyelid, (3) fast opening and closing of the eyelids, and (4) clenching. The electrodes were placed in the fascicles of upper (UO) and lower (LO) orbicular muscles. Electromyographic examinations were performed before and after 7, 14, 30 and 60 days of prosthesis insertion. T-test (p<.05) was used to compare the upper and lower orbicular muscles for each period of evaluation in all clinical conditions. A total of 12 patients of both genders were treated and they aged from 42 to 80 years. Several factors were the cause of anophthalmia and the trauma during job accident was the main reason. A statistical significant difference in the electromyographic data was observed for all four clinical conditions when comparing the baseline with the 7-day prosthesis insertion periods. The UO exhibited higher values of electrical activity than LO for all clinical situations. The lowest electrical activity was noted for the baseline period during the rest condition (UO 8.418 /LO 5.933), while the greatest one after 60 days of prosthesis insertion during clenching (UO 131.504 / LO 117.123). After ocular prosthesis insertion, a significant increase in the electrical activity values of the orbicular muscles was observed.

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Santos, Murillo Rezende. "Atividade elétrica dos músculos orbiculares antes e após a instalação de próteses oculares /." Araçatuba, 2013. http://hdl.handle.net/11449/97365.

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Orientador: Daniela Micheline dos Santos
Co-orientador: Marcelo Coelho Goiato
Banca: Eduardo Piza Pellizzer
Banca: Aldiéris Alves Pesqueira
Resumo: A perda do bulbo ocular compromete não só a estética, mas também a tonicidade muscular da região facial do paciente, uma vez que com a ausência do globo ocular os músculos orbiculares dos olhos podem sofrer atrofia. Desse modo, o objetivo do presente estudo foi verificar a atividade elétrica dos músculos orbiculares, antes e após a instalação de próteses oculares em pacientes que foram submetidos à enucleação unilateral do bulbo ocular. Foram selecionados, por meio de anamnese e exame clínico, 12 pacientes voluntários com indicação de prótese. O sinal eletromiográfico foi realizado com o auxílio do eletromiógrafo, em quatro situações clínicas: Repouso (R), Abertura e Fechamento Normal das Pálpebras (AFN), Abertura e Fechamento Rápido das Pálpebras (AFR) e Apertamento (A). Esses registros foram realizados antes da instalação da prótese ocular, e após 7, 30 e 60 dias da instalação e uso da mesma. Os mesmos ensaios foram realizados no músculo orbicular do olho sadio do paciente, resultados que serviram como controle do estudo. Os dados obtidos foram submetidos à análise estatística pelo programa SPSS (p<0.05) e o t-teste foi utilizado para comparar os músculos superior e inferior por período de tratamento (inicial, 7, 14, 30 e 60 dias), para as quatro condições clínicas. Nas quatro condições clínicas avaliadas foi verificado diferença estatisticamente significativa em relação ao período inicial e após 7 dias da instalação da prótese. O fascículo superior do músculo orbicular do olho apresentou maiores valores de atividade elétrica em relação ao fascículo inferior em todas as situações clínicas avaliadas. Os menores valores de atividade elétrica foram observados durante o período inicial para a condição de repouso (OS 8.418 / OI 5.933) e os maiores após 60 dias na condição...
Abstract: The eye loss besides affecting patient's aesthetics, it compromises the muscle tone of the facial region owing to the atrophy of orbicular muscles. Thus, although the use of ocular prosthesis does not return patient's vision, it fills the anophtalmic cavity restoring the cosmetic and muscle tone. The aim of this present study was to evaluate the electrical activity of orbicular muscles before and after ocular prosthesis insertion of patients who underwent unilateral enucleation of eyeball. The electrical activity of the orbicular muscles was assessed through the Myosystem BR1 electromyograph in four clinical situations: (1) rest, (2) normal opening and closing of the eyelid, (3) fast opening and closing of the eyelids, and (4) clenching. The electrodes were placed in the fascicles of upper (UO) and lower (LO) orbicular muscles. Electromyographic examinations were performed before and after 7, 14, 30 and 60 days of prosthesis insertion. T-test (p<.05) was used to compare the upper and lower orbicular muscles for each period of evaluation in all clinical conditions. A total of 12 patients of both genders were treated and they aged from 42 to 80 years. Several factors were the cause of anophthalmia and the trauma during job accident was the main reason. A statistical significant difference in the electromyographic data was observed for all four clinical conditions when comparing the baseline with the 7-day prosthesis insertion periods. The UO exhibited higher values of electrical activity than LO for all clinical situations. The lowest electrical activity was noted for the baseline period during the rest condition (UO 8.418 /LO 5.933), while the greatest one after 60 days of prosthesis insertion during clenching (UO 131.504 / LO 117.123). After ocular prosthesis insertion, a significant increase in the electrical activity values of the orbicular muscles was observed.
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4

Matos, Rhowena Jane Barbosa de. "Expressão dos receptores metabotrópicos de glutamato no sistema visual de ratos e pintos após enucleação ocular." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/42/42137/tde-04012008-152915/.

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Os receptores glutamatérgicos metabotrópicos (mGluRs) estão envolvidos nos processos de plasticidade, neurodegeneração e neuroproteção. Avaliamos a expressão de mGluRs no sistema visual de ratos e pintos em diferentes tempos após enucleação ocular. Os animais foram avaliados pelo método de imuno-histoquímica, immunoblotting e RT-PCR, para detecção dos receptores mGluR1,2/3,5 e 7. Foi observado aumento da imunorreatividade (IR) de mGluR1, 5 e 7 no colículo superior, porém não foi observada diferença no núcleo geniculado lateral. Houve aumento na expressão protéica para mGluR1, 5 e 7 e aumento da expressão gênica para mGluR1,5 e 7; por outro lado, ocorreu uma diminuição de mGluR3. No TeO, foi observado aumento da IR para mGluR1 e 5 e diminuição para mGluR2/3. As análises de immunoblotting confirmaram o aumento observado de mGluR1 e diminuição de mGluR2/3. Os resultados indicam uma modulação diferencial na expressão gênica e protéica dos mGluRs, sugerindo a participação desses receptores em processos plásticos decorrentes de lesões no sistema visual adulto.
The metabotropic glutamate receptors (mGluRs) are involved in neuronal plasticity and neuroprotection. We analyzed the expression of mGluRs in the visual system of rats and chicks in several periods after ocular enucleation. The localization and expression of mGluR1, 5, 2/3 and 7 receptors were evaluated by standard immunoperoxidase, immunoblotting and real-time PCR protocols. The immunorreativity, protein and gene expression of mGluR1, 5 and 7 receptors in the superior colliculus showed an increase, whereas no changes were seen in the lateral geniculate nucleus. For mGluR3, gene expression was decreased. In the TeO, mGluR1 and 5 increased for all survival periods analyzed. Immunoblotting analyses confirmed the increases for mGluR1 and 5, decreases for mGluR2/3. These results indicate that the expression of mGluRs is regulated by the glutamatergic retinal input, and add data on a possible role of these receptors in neuroplasticity in adult animals.

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Lins, Otavio G. "Ocular artifacts in recording EEGs and event related potentials." Thesis, University of Ottawa (Canada), 1993. http://hdl.handle.net/10393/6889.

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The ocular artifacts derive from the potential difference between the cornea and the fundus of the eye. This can be represented by an equivalent dipole with its positive pole directed toward the cornea. The DC potential between the cornea and the forehead measures approximately +13 mV. The scalp-distribution of the ocular artifacts can be described in terms of propagation factors--the percentage of the EOG present at the EEG electrodes. These factors are significantly different for blinks and upward eye-movements. The source dipoles for blinks and saccades are different--blink dipoles point radially whereas saccade dipoles point tangentially, in the direction of the eye movement. Blink and eye movement potentials are generated by different mechanisms--blink potentials are generated by the eyelid sliding over the cornea, eye movement potentials by the rotation of the ocular dipole. A very small downward rotation of the eyes may occur during a normal blink. The "rider artifact" at the onset of upward saccade is caused by the eyelid as it lags behind the eyes at the beginning of the movement. Smaller rider artifacts, caused by the horizontal asymmetry of the eyelid, can be noted during horizontal but not downward saccades. Techniques that use scaled EOG to remove ocular artifacts from EEG recordings may remove some of the frontal EEG together with the ocular artifacts. Dipole source techniques allow the ocular generators to be distinguished from the nearby brain generators. A problem with dipole source techniques is that the head model used in the calculation is not accurate at the eyes. A new technique uses principal component analysis to estimate the ocular artifact at each electrode without using a head model. This technique is the most effective way to remove ocular artifacts from EEG recordings. (Abstract shortened by UMI.)

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Daviet, Philippe Marc Cyrille. "Models of ocular dominance stripes and orientational selectivity." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=60481.

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Neurons on layer IV of the primate visual cortex undego changes in connections before and after birth leading to the formation of ocular dominance and orientational selective stripes. We model these changes by an intra-cortical interaction which can in turn be represented by a one-component (Ising-like) model for ocular dominance and a two-component (XY-like) model orientational selectivity. We study these systems numerically by Monte Carlo simulation and by solving Langevin equations. Both models give evidence of stripe, hexagonal, and paramagnetic phases. We discuss the relationship of these phases and of defect formation to experimental results from physiology.

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Blanco, Paula L. "Characterization of ocular and metastatic uveal melanoma in an animal model." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=81599.

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Uveal melanoma is the most common primary malignant intraocular tumor in adults. The management of uveal melanoma remains a clinical dilemma, which reflects our poor understanding of this life-threatening disease. A major challenge facing researchers investigating this malignancy has been to develop a suitable animal model. The purpose of this work is to characterize, in detail, the processes of tumor development, malignant cell dissemination and metastasis in a 10-week albino rabbit model of uveal melanoma. Intraocular tumors successfully developed, and metastatic disease was present in all animals at the end of the experiment. For the first time using an animal model of uveal melanoma, the presence of circulating malignant cells in the bloodstream was demonstrated. Knowledge gained from this study has led to a better overall understanding of the progression of the disease in this experimental model and may facilitate the development of methods for the prevention, early detection and treatment of metastatic uveal melanoma.

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Ito, Célia Regina Malveste. "A avaliação do efeito de antissépticos na superfície ocular e o papel da gentamicina no controle microbiano de córneas doadas." Universidade Federal de Goiás, 2017. http://repositorio.bc.ufg.br/tede/handle/tede/8115.

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Decontamination of the surface of the donor eyeballs is part of the operational norms that eye banks advocate before preservation, and antisepsis procedures are effective, ensuring greater transplantation safety. The objective of the present study was to evaluate the antiseptic effect in reducing the microbiota of the ocular globe of donors of corneas prior to enucleation, with 5% povidone-iodine (PVP-I) and 0.05% chlorhexidine gluconate (GC), In the action times of 5, 10 and 15 minutes, as well as the susceptibility profile of the microbiota isolated from gentamicin. Thirty pairs of corneas received antiseptics, with PVP-I in the right eye and GC in the left, and for each time of action 10 pairs of eyeballs were used. Swabs were collected from the ocular surface before application of the solutions, after and at the time of preservation of the corneal tissue, to evaluate the reduction of the microbiota. After identification of the microbiota, an antibiogram test was performed with gentamicin. The data were computed and evaluated by Chi-square or Fisher's exact test, T-test and McNemar test paired, and the statistical significance level was 5% (p <0.05). In the second collection, after antisepsis, there was a reduction of 39,5% in the total of gram positive bacteria (G +), and of 76,5% in the gram negative (G-) bacteria, with no statistically significant difference (p = 0.183), which demonstrated that the bacterial elimination capacity of the antiseptics was similar. It was observed that, in the second collection, both were more effective for G-, with a statistically significant difference (p <0.001), than for G +, with no statistically significant difference (p = 0.494). In the third collection, after the residual effect of the antiseptics, there was a reduction of 99.1% of all the microorganisms. In the antibiogram test, 88% of the isolated microorganisms were sensitive to gentamicin. It was concluded that the use of antiseptics is essential for the effective decontamination of donated corneas prior to preservation. The residual time of the antiseptics increased the decontamination power of PVP-I and GC, being similar in reducing the microbiota of the ocular globe of the donor of corneas. Gentamycin contained in the cornea preservation medium complements the antisepsis of the donated tissues.
A descontaminação da superfície dos globos oculares doados são normas operacionais que os bancos de olhos preconizam antes da preservação e os procedimentos de antissepsia são eficazes, garantindo uma maior segurança ao transplante. O objetivo do presente estudo foi avaliar o efeito antisséptico na redução da microbiota do globo ocular de doadores de córneas antes da enucleação, com o povidona-iodo (PVP-I) a 5% e gluconato de clorexidina (GC) a 0,05%, nos tempos de ação de 5, 10 e 15 minutos, bem como o perfil de susceptibilidade da microbiota isolada à gentamicina. Trinta pares de córneas receberam antissépticos, sendo o PVP-I no olho direito e o GC no esquerdo, e para cada tempo de ação foram utilizados 10 pares de globos oculares. Foram colhidos swabs da superfície ocular antes da aplicação das soluções, após e no momento da preservação do tecido corneano, para avaliar a redução da microbiota. Após identificação da microbiota, foi realizado teste de antibiograma com gentamicina. Os dados foram computados e avaliados pelos testes Qui-Quadrado ou Exato de Fisher, teste T e Teste McNemar pareado, e o nível de significância estatística foi (p<0,05). Com relação aos dados obtidos na segunda coleta, após o uso de antissépticos, houve uma redução de 39,5% no total de bactérias gram positivas (G+) e de 76,5% nas gram negativas (G-), não havendo diferença estatística significativa (p=0,183), sendo semelhante a capacidade de eliminação bacteriana dos antissépticos. Observa-se que, na segunda coleta, ambos foram mais eficazes para as G-, com diferença estatisticamente significativa (p<0,001), do que para as G+, sem diferença estatisticamente significativa (p=0,494). Na terceira coleta, após o efeito residual dos antissépticos, houve redução de 99,1% de todos os micro-organismos. No teste de antibiograma, 88% dos micro-organismos isolados foram sensíveis à gentamicina. Concluiu-se que o uso de antissépticos é essencial para a efetiva descontaminação das córneas doadas antes da preservação. O tempo residual dos antissépticos aumentou o poder de descontaminação do PVP-I e GC, sendo semelhantes na redução da microbiota do globo ocular do doador de córneas. A gentamicina contida no meio de preservação de córnea complementa a antissepsia dos tecidos doados.

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Estanislau, Cristiane de Abreu. "Biometria ocular na espécie Cebus apella /." Botucatu, 2014. http://hdl.handle.net/11449/124011.

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Orientador: José Joaquim Titton Ranzani
Banca: Cláudia Valéria Seullner Brandão
Banca: Antônio Carlos Rodrigues
Resumo: O objetivo deste trabalho foi determinar as dimensões oculares dos macacos-prego por meio de ultrassonografia modo-A e ceratometria, e determinar o poder dióptrico da lente intraocular empregando-se fórmulas de terceira e quarta geração. Foram utilizados 18 animais (36 olhos) da espécie Cebus apella. O cálculo da lente intraocular foi realizado utilizando-se o software Holladay IOL Consultant® e EyeCalculator 6.0®. As fórmulas empregadas para o cálculo foram Holladay 2, Haigis e Hoffer Q que possibilitaram prever lentes com poder dióptrico médio de 29,43 D; 31,25D e 46,71D, respectivamente. Não foi observado diferença estatística entre os valores dióptricos das lentes calculadas pelas fórmulas Holladay 2 e Haigis; no entanto, com a aplicação da fórmula Hoffer Q observou-se diferença estatística, determinando lentes mais potentes. Considerando os parâmetros biométricos oculares avaliados, e o poder dióptrico calculado por uma mesma fórmula não há diferenças significativas entre machos e fêmeas, e lateralidade dos olhos para um mesmo animal
Abstract: The aim of this study was to determine the ocular dimensions of capuchin monkeys using ultrasound A and keratometry, determining the refractive power of the IOL formulas employing third and fourth generation. Were used 18 animals (36 eyes) of the species Cebus apella. The calculation of intraocular lens was performed using the Holladay IOL Consultant ® and EyeCalculator ® 6.0 software. Holladay 2, Hoffer Q, and Haigis formulas were employed to do the calculus and determin lenses with an average refractive power of 29.43 D; 31.25 D and 46.71 D, respectively. No statistical difference was observed between the lens dioptric values calculated by formulas Holladay 2 and Haigis; however, we could see statistical difference between groups when the the formula Hoffer Q was applied, resulting in more powerful lenses. The reviews of ocular biometric parameters and the lens power calculated by the same formula showed neither significant differences between males and females, or between the right and left eyes of each animal
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Estanislau, Cristiane de Abreu [UNESP]. "Biometria ocular na espécie Cebus apella." Universidade Estadual Paulista (UNESP), 2014. http://hdl.handle.net/11449/124011.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
O objetivo deste trabalho foi determinar as dimensões oculares dos macacos-prego por meio de ultrassonografia modo-A e ceratometria, e determinar o poder dióptrico da lente intraocular empregando-se fórmulas de terceira e quarta geração. Foram utilizados 18 animais (36 olhos) da espécie Cebus apella. O cálculo da lente intraocular foi realizado utilizando-se o software Holladay IOL Consultant® e EyeCalculator 6.0®. As fórmulas empregadas para o cálculo foram Holladay 2, Haigis e Hoffer Q que possibilitaram prever lentes com poder dióptrico médio de 29,43 D; 31,25D e 46,71D, respectivamente. Não foi observado diferença estatística entre os valores dióptricos das lentes calculadas pelas fórmulas Holladay 2 e Haigis; no entanto, com a aplicação da fórmula Hoffer Q observou-se diferença estatística, determinando lentes mais potentes. Considerando os parâmetros biométricos oculares avaliados, e o poder dióptrico calculado por uma mesma fórmula não há diferenças significativas entre machos e fêmeas, e lateralidade dos olhos para um mesmo animal
The aim of this study was to determine the ocular dimensions of capuchin monkeys using ultrasound A and keratometry, determining the refractive power of the IOL formulas employing third and fourth generation. Were used 18 animals (36 eyes) of the species Cebus apella. The calculation of intraocular lens was performed using the Holladay IOL Consultant ® and EyeCalculator ® 6.0 software. Holladay 2, Hoffer Q, and Haigis formulas were employed to do the calculus and determin lenses with an average refractive power of 29.43 D; 31.25 D and 46.71 D, respectively. No statistical difference was observed between the lens dioptric values calculated by formulas Holladay 2 and Haigis; however, we could see statistical difference between groups when the the formula Hoffer Q was applied, resulting in more powerful lenses. The reviews of ocular biometric parameters and the lens power calculated by the same formula showed neither significant differences between males and females, or between the right and left eyes of each animal

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May, Leigh A. "The production and characterisation of transgenic disease models for retinal ocular neovascularisation." University of Western Australia. Centre for Ophthalmology and Visual Science, 2004. http://theses.library.uwa.edu.au/adt-WU2006.0047.

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[Truncated abstract] One of the barriers to understanding and preventing proliferative diabetic retinopathy in humans has been the lack of an appropriate animal model. Historically dog, rat and mouse models of diabetic retinopathy have been studied but none of these exhibit the later changes of proliferative diabetic retinopathy. Animals can be rendered diabetic by surgical pancreatectomy or the use of chemicals such as allozan or streptozotocin or by feeding of a high galactose diet. Alternatively, spontaneous rodent models of diabetes have been examined such as the BB rat, KK mouse or NOD mouse. However, in each case the retinal vascular changes observed are those of early nonproliferative diabetic retinopathy comprising at most saccular microaneurysms, increased thickness of the capillary basement membrane, acellular capillaries and pericyte ghosts. … Fluorecein angiography of this transgenic line clearly demonstrates the presence of leaky new vessels, by the appearance of leakage spots scattered throughout the retina from 1 month of age. These mice constitute a valuable model of diabetic retinopathy. Neovascularization in this animal model is induced by VEGF as in human diabetic retinopathy. The source of VEGF in human diabetic retinopathy is the ischemic inner retina. In this transgenic model the source of VEGF are the photoreceptor cells, which are situated just underneath the inner retina. The neovascularization is not dependent on a particular developmental stage and there is no spontaneous regression of new vessels. Thus any results generated in this model are highly relevant to human diabetic retinopathy.

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12

ARAÚJO, Sidcley Bernardino de. "Biointegração do gel celulósico produzido pela zoologleasp a partir do melaço da cana-de-açúcar em olhos eviscerados de coelhos." Universidade Federal de Pernambuco, 2016. https://repositorio.ufpe.br/handle/123456789/22397.

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Investigar características do processo de integração e biocompatibilidade de um implante de gel celulósico nas cavidades anoftálmicas de coelhos. Analisar a proliferação celular em geral, a angiogênese, a proliferação de células multinucleadas gigantes e a fibrogênese, por técnicas de histomorfométria e imunohistoquímica. Estudo experimental de intervenção empregando 18 coelhos divididos em 6 grupos. O olho direito de todos os animais foi eviscerado e os esquedo não sofreu nenhum tipo de intervenção. Após a evisceração a bolsa escleral foi suturada e preenchida com gel celulósico gel. Diariamente, todos os animais foram examinados clinicamente, sob biomicroscopia, até o 7º dia do implante e uma vez por semana até o dia da eutanásia. Os animais foram submetidos a eutanásia e enucleações dos olhos no 7º, 30º, 60º, 90º, 120º e 240º dia após o implante. Os olhos, inclusive os esquerdos, foram avaliados macroscopicamente e processados para análises histopatológica, histomorfométricas, imunohistoquímicas e imunofluorescência. Clinicamente, todos os animais, não exibiram sinais de alergias, intoxicação, extrusão e infecção. Em todos os grupos ao exame macroscópico, histopatológico e histomordo olho esquerdo, não revelou alterações anatômicas. No entanto, nesta análise, olho direito exibiu redução de 8% no volume do bulbo. O corte do saco escleral mostrou um conteúdo sólido, compacto, elástico, resistente à tração, com superfície lisa e brancacenta.Não foram observados sinais de necrose, ou liquefação. O tecido epiescleral estava algo hipertrofiado. As preparações histológicas estudadas, nas diversas colorações, revelaram uma infiltração linfomonomorfonuclear inicial, substituída posteriormente por uma proliferação fibrocitária e histiocitária com formação de células multinucleadas gigantes. Foram também encontrados poucos polimorfonucleares neutrófilos e eosinófilos. A partir do 30o dia houve proliferação vascular e deposição de colágeno em todos os espécimes estudados, embora, no 240º dia do experimento, a resposta inflamatória crônica, a neovascularização e a deposição do colágeno não tinham ainda atingido o centro do implante. Neste modelo, o gel da celulose produzido pela Zoogleia sp, mostrou-se biocompatível e integrado às órbitas. Fica, portanto, comprovado que o gel celulósico, utilizadoneste experimento, além de biocompatível, se integrou às órbitas dos coelhos.
To evaluate histologically the integration process of cellulose gel produced by Zoogloea sp when implanted into rabbits’ eviscerated eyes. This experimental study employed 36 eyes of 18 rabbits subjected toEvisceration of their right eyes. The sclerocorneal bag was sutured and filled withbiopolymer from sugar cane in the gel state. All animals were clinically examinedby biomicroscopy until the day of their sacrifice which occurred on the 7º, 30º, 60º, 90º, 120º, or 240º day. The eyeballs obtained, including the left eyes considered controls were sent for histopathological study by optical macroscopyand microscopy. Tissue staining techniques used included hematoxylin-eosin, Masson trichrome (with aniline), Gomori trichrome, Van Gienson, Picrosirius red and periodic acid-Schiff (PAS). No clinical signs of infection, allergy, toxicity, or extrusion were observed throughout the experiment. The corneas were relatively preserved. Macroscopic examination revealed a decrease of ~ 8% in the volume of the bulbs implanted with the biopolymer. After cutting, the sclerocorneal bag was solid, compact, elastic, and resistant to traction, with a smooth and whitish surface, and showed no signs of necrosis or liquefaction. The episcleral tissues were somewhat hypertrophied. The histological preparations studied in different colors revealed an initial lymphoplasmacytic infiltration, replaced by a fibroblastic response and proliferation of histiocytes, along with formation of giant cells. Few polymorphonuclearneutrophils and eosinophils were also found. Neovascularization and collagen deposition were present in all animals starting from day 30; although on the 240º day of the experiment the chronic inflammatory response, neovascularization and collagen deposition had not yet reached the center of the implant. In this model, the cellulose gel produced by Zoogloea sp proved to be biocompatible and integrated into the orbits.

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13

Banz, Kelly. "Calming the ocular storm : the effect of corticosteroids in inflammatory oedema." University of Western Australia. Faculty of Life and Physical Sciences, 2009. http://theses.library.uwa.edu.au/adt-WU2009.0093.

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The primary aim of this research is to test the therapeutic potential of certain new generation corticosteroid drugs in order to develop safe and effective treatment for eye diseases that result in oedema, or swelling. The rising incidence of diabetes and the ageing population of developed countries mean that the prevalence of uveitis, diabetic retinopathy and age related macular degeneration will rise. Often, oedema is one of the reasons for vision loss. Corticosteroids are often used to reduce inflammation. Inflammation is one of several sources of oedema. Glucocorticoids, a class of corticosteroids that have anti-inflammatory properties, are thus used to treat ocular oedema. There is an unmet need to support clinical experience of the efficacy of steroids for ocular inflammation and oedema with more substantial scientific evidence. None of the drugs under investigation, with the exceptions of dexamethasone and triamcinolone, have been used for any ocular therapeutic purpose before. This thesis investigates repurposing fludrocortisone to the ophthalmic area. 11-Desoxycorticosterone (11D) and Deoxycorticosterone (DCS), other potentially valuable mineralocorticoids, remain completely untested. Lastly, Kenacort ®, or triamcinolone acetonide (TCA), is only used off-label by ophthalmologists. Methods: In the first study, corticosteroids, and especially mineralocorticoids, were investigated for their treatment efficacy in experimental uveitis, or intraocular inflammation (using a model known as endotoxin induced uveitis). In the second study, endothelial cells from choroidal blood vessels in the back of the eye were used in vitro to study whether corticosteroids reduce paracellular (between cells) permeability. Lastly, since endophthalmitis due to frequent injections is a side effect of corticosteroid use, the pharmacokinetics of different size formulations of corticosteroids were studied in an effort to find a formula that would have a prolonged dwell time within the eye.

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14

Fuoco, Gabriel. "Objective and clinical assessment of vestibular function using new vestibulo-ocular and vestibulospinal tests : net gaze stabilization and active comfortable torsal-head rotation." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=22732.

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There exists no adequate objective measure of vestibular function and consequently clinicians cannot easily estimate degree of vestibular dysfunction or dizziness. This study aimed to evaluate new objective measures of vestibular function by determining (1) how these measures relate to subjective clinical estimates of vestibular function and (2) whether these measures can identify patients with true vestibular dizziness.
Net $ {$slow-phase + saccadic$ }$ gaze stabilization and active comfortable torsal-head rotation were used to objectively characterize vestibulo-ocular and vestibulospinal function, respectively, in 39 dizzy patients and 30 normals. Blinded clinical ranking of apparent vestibular function of the patients was obtained from history and clinical examination.
It was found (1) that clinical rankings were significantly correlated (r$ rm sb{s}$:0.39, p $<$ 0.02) to a new objective parameter based on both vestibulo-ocular and vestibulospinal measures, and (2) that an objective measure of both vestibulo-ocular and vestibulospinal function permitted most dizzy patients and normal subjects to be identified (sensitivity: 87%, specificity: 83%).

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15

LIMA, Aline Maria Vasconcelos. "Produção lacrimal e densidade de células caliciformes conjuntivais em cães da raça SHIH-TZU." Universidade Federal de Goiás, 2008. http://repositorio.bc.ufg.br/tede/handle/tde/842.

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Considering the relevance of tear production and tear quality to the conservation of the corneal health, the present study aimed to evaluate tear production and conjunctival goblet cells density in Shih-tzu dogs. Thirty five grownup Shih-tzu dogs, including 33 females and 2 males, were subjected to Schirmer tear test 1 (STT-1) and Schirmer tear test 2 (STT-2). Among these dogs, fourteen females and one male were underwent to conjunctival biopsy for histologic evaluation of goblet cell density (GCD) and goblet cell index (GCI). The STT-1 mean values found were 19,66 ± 7,3 mm/min for left eye (LE) and 21,97 ± 5,7 mm/min for right eye (RE). The STT-2 mean values were 10,71 ± 6,1 mm/min and 9,14 ± 4,78 mm/min for LE and RE, respectively. The GCD mean values found were 13,64 ± 3,44 goblet cells/50 epithelial cells for LE and 13, 64 ± 4,07 goblet cells/50 epithelial cells for RE. The GCIs correspondent were 0,27 ± 0,069 and 0,27 ± 0,081 for LE and RE, respectively. There was significant difference between LE and RE STT-1 values. There was not significant difference between eyes for STT-2, GCD and GCI values. STT-1 and STT-2 values did not influence significantly GCI values. STT-1 and STT-2 values are within of the pattern considered normal, but the GCD and GCI mean values are lower than those values described in literature for healthy dogs of other breeds. The conjunctival specimens histological evaluation was accepted as convenient, which demonstrated squamous metaplasic areas in 83,3% of the specimens. Within 44% of these, squamous metaplasia was predominantly associated with mononuclear inflammatory infiltrate.
Considerando a importância da produção e qualidade lacrimal para a manutenção de uma córnea saudável, o presente trabalho objetivou avaliar a produção lacrimal e a densidade de células caliciformes conjuntivais em cães da raça Shih-tzu. Trinta e cinco cães Shih-tzu, sendo 33 fêmeas e dois machos, adultos, foram submetidos aos testes lacrimais de Schirmer 1 (TLS-1) e 2 (TLS-2). Destes animais, quatorze fêmeas e um macho foram submetidos à biópsia conjuntival para avaliação histológica da densidade e índice de células caliciformes conjuntivais (DCC e ICC). Os valores médios obtidos de TLS-1 para os cães estudados foram de 19,66 ± 7,3 mm/min para o olho esquerdo (OE) e de 21,97 ± 5,7 mm/min para o direito (OD). Os valores do TLS-2 foram de 10,71 ± 6,1 mm/min e de 9,14 ± 4,78 mm/min para OE e OD, respectivamente. A densidade média de células caliciformes (células caliciformes / 50 células epiteliais) encontrada foi de 13,64 ± 3,44 e 13, 64 ± 4,07 para os olhos esquerdo e direito, respectivamente. Os índices de células caliciformes médios correspondentes foram de 0,27 ± 0,069 para o olho esquerdo e de 0,27 ± 0,081 para o olho direito. Houve diferença significativa entre os olhos esquerdo e direito para TLS-1. Não houve diferença significativa entre os olhos para TLS-2, DCC e ICC. Os valores de TLS-1 e TLS-2 não influenciaram significativamente os valores de ICC. Os valores de TLS-1 e 2 encontrados para os animais avaliados se encontram dentro dos padrões considerados normais, mas os valores médios de ICC e DCC são inferiores aos valores descritos na literatura para cães hígidos de outras raças. Admitiu-se como oportuna a avaliação histológica dos fragmentos conjuntivais biopsiados, a qual revelou presença de áreas de metaplasia escamosa em 83,3% das lâminas avaliadas. Destas, 44% apresentavam metaplasias associadas a infiltrados inflamatórios predominantemente mononucleares.

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16

Green, Andrea Michelle. "Visual-vestibular interaction in a bilateral model of the rotational and translational vestibulo-ocular reflexes : an investigation of viewing-context-dependent reflex performance." Thesis, McGill University, 2000. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=36810.

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Traditionally, the vestibulo-ocular reflex (VOR) has been considered a stereotyped ocular counterrotation response to head movement that stabilizes a visual image on the retinae. However, during natural head movements, the appropriate magnitudes and directions of compensatory ocular deviations depend on viewing context. Moment-to-moment adjustments in VOR performance are required as gaze is redirected towards different viewing locations.
This thesis presents an investigation of viewing-context-dependent VOR performance through the development of a physiologically and anatomically based bilateral model structure. Previous theoretical studies of visual-vestibular interactions during head-centered rotation are extended by simulating both ocular responses and those of individual premotor brainstem neuron types in an integrated binocular controller for slow eye movements. Central sensitivities to vestibular canal signals are modulated as a function of instantaneous binocular fixation state to simulate appropriate viewing-location-dependent changes in monocular rotational VOR performance and distinct premotor cell behaviors.
A new hypothesis for the central dynamic processing of sensory otolith signals in the translational VOR is presented. Previous proposals suggested that the unique dynamic characteristics of otolith and canal afferent signals imply additional central processing in the translational as compared to the rotational VOR pathways. The strategy presented here demonstrates that projecting canal and otolith signals onto a shared premotor circuit at unique sites is sufficient to reproduce observed ocular and central behaviors without introducing additional central filters. By implementing this simple strategy in the bilateral model structure the ability to achieve appropriate compensatory responses for different translation directions and viewing locations in the horizontal plane is demonstrated.
Finally, the model is extended to incorporate brainstem-cerebellar interactions. Current conclusions surrounding potential central sites for plasticity underlying long-term VOR gain adaptation are evaluated. The work makes new suggestions for vestibulo-ocular system organization and proposes directions for experimental work in addressing the following general themes: (1) Sensory convergence onto a shared premotor controller; (2) The role of a bilateral topology in motor pattern selection and binocular coordination; (3) The role of central connectivity in the appearance of distinct premotor cell types; (4) The ability to localize central sites for modifications underlying viewing-location-dependent and long-term adaptive changes in reflex performance.

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Piveta, Lidiana Cândida. "Uso da tenecteplase no transoperatório de coelhos hígidos tratados com facoemulsificação." Universidade Federal de Goiás, 2016. http://repositorio.bc.ufg.br/tede/handle/tede/6463.

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Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq
Cataracts is the treatable eye diseases that cause most blindness in the world. The effective treatment is surgical and phacoemulsification the most applied technique. Some complications are associated with the procedure as corneal opacities, uveitis and fibrin deposits. The presence of fibrin in the anterior chamber is associated with the formation of synechia and secondary glaucoma low visual recovery of patients. Some medications, as TPA (Tissue Plasminogen Activator) which acts in the degradation of fibrin, seeing being used to soften these deposits. Tenecteplase is a third generation of the synthetic TPA and have a longer half-life than the others with application in ophthalmology without damage to the cornea and retina of rabbits and humans. The study was conducted on 15 rabbits of New Zealand race, share in three groups GC, GT and GNT. The GNT and GT were surgery by phacoemulsification technics, GT was treated with 0.1 ml intracameral tenecteplase (50 μg) transoperative. The rabbits were evaluated in M0 moments - when selected, underwent phacoemulsification surgery and reassessed in M1d – 1th day M3d – 3th day M7d – 7th day M15d - 15th day and M21d – 21th days. In the clinical evaluation of the use of intracameral tenecteplase in transoperative and postoperative complications were observed, emphasizing the change in IOP, the corneal edema, fibrin deposits, hyphema, aqueous flare and synechia incidences. In the M21d animals were sacrificed, and samples of aqueous humor were collected for physical-chemical analysis (pH, density, concentration of chloride ions and total proteins). No statistical differences were observed in the clinical evaluation of the GC and GNT within the recommended parameters. In physical-chemical analysis of aqueous humor showed no statistical difference between the three groups in terms of pH and concentration of chloride ion. The density values and total protein concentration between the GC and the other groups.
A catarata está entre as oftalmopatias tratáveis que mais causam cegueira no mundo. O único tratamento efetivo é cirúrgico, sendo a facoemulsificação a técnica mais aplicada. Algumas complicações estão associadas ao procedimento como opacidades corneanas, uveítes e depósitos de fibrinas. A presença de fibrina na câmara anterior esta associada à formação de sinéquias, glaucoma secundário e baixa recuperação visual dos pacientes. Algumas medicações vêm sendo usadas para amenizar esses depósitos como os TPA, que atua na degradação da fibrina. A tenecteplase é um TPA sintético de terceira geração que apresenta um tempo de meia vida maior que as outras gerações, com aplicação na oftalmologia sem danos à córnea e retina de coelhos e humanos. O estudo foi realizado com 15 coelhos da raça Nova Zelândia, divididos em três grupos GC, GNT e GT. Os grupos GNT e GT foram operados pela técnica de facoemulsificação, GT recebeu tratamento com 0,1 ml de tenecteplase intracameral (50μg) no transoperatório. Os coelhos foram avaliados nos momentos M0 - quando selecionados, submetidos ao procedimento cirúrgico de facoemulsificação e reavaliados em M1d - 1° dia, M3d - 3°dia, M7d - 7 °dia, M15d - 15° dia e M21d - 21°dia. Na avaliação clínica do uso da tenecteplase intracameral no transoperatório foram observadas as complicações pós-operatórias, dando ênfase à variação da pressão intraocular (PIO), ao edema de córnea, depósito de fibrina, hifema, flare aquoso e incidências de sinéquias. No M5 os animais foram eutanasiados, e coletado amostras do humor aquoso para avaliação físico-química (pH, densidade, concentração de íons de cloreto e proteínas totais). Não foram observadas diferenças estatísticas na avaliação clínica entre o GNT e GT dentro dos parâmetros preconizados. Na avaliação físico-química do humor aquoso não apresentou diferença estatística entre os três grupos quanto aos valores de pH e concentração do íon cloreto. Os valores de densidade e concentração de proteínas totais entre o GC e os demais grupos.

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18

Kezic, Jelena Marie. "A study of the monocyte-derived cell populations of the uveal tract and retina in homeostatic conditions and during the early stages of ocular autoimmune disease." University of Western Australia. School of Anatomy and Human Biology, 2008. http://theses.library.uwa.edu.au/adt-WU2009.0084.

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The eye contains closely related but widely different tissues, offering a unique opportunity to investigate the phenotype and function of monocyte-derived cell populations within functionally unique microenvironments in a single complex organ. The uveal tract and retina contain rich networks of immune cells that reside and traffic through the eye, these cells having been implicated in various ocular inflammatory processes and immune-mediated diseases. One such inflammatory condition is human posterior uveitis, an autoimmune disease mainly affecting the retina. As current treatments for posterior uveitis only serve to slow down disease progression, studies using animal models, namely, experimental autoimmune uveoretinitis (EAU), have focused on determining the key cellular and molecular mediators involved in disease initiation in order to expand the potential for novel therapeutic applications. The overall purpose of experiments in this thesis was to explore monocyte-derived cell populations of the uveal tract and retina, this being achieved by utilising a novel transgenic mouse model. Cx3cr1gfp/gfp transgenic mice on both BALB/c and C57Bl/6 backgrounds contain an enhanced green fluorescent protein (eGFP) encoding cassette knocked into the Cx3cr1 gene, disrupting its expression but facilitating GFP expression under the control of the Cx3cr1 promoter. Heterozygous (Cx3cr1+/gfp) mice were generated by crossing Cx3cr1gfp/gfp mice to wild-type (WT) mice. This transgenic model allowed for the exquisite visualisation of Cx3cr1-bearing monocyte-derived dendritic cells (DC) and macrophages in ocular tissues, whilst also enabling the investigation of a potential role for Cx3cr1 in recruiting monocyte-derived cells to the eye in steady-state and inflammatory conditions.

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19

Lacordia, Marta Halfeld Ferrari Alves. "Estudo comparativo da ação da toxina botulínica tipo A e da crotoxina sobre as células satélites da musculatura extrínseca ocular em modelo animal." Universidade Federal de Minas Gerais, 2007. http://hdl.handle.net/1843/RRSA-7BMFCV.

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Introduction: When muscle lesions occur, the satellite cells spring into action, by dividing and either repairing damaged fibers or forming new myofibers. Unlike skeletal muscle which is postmitotic, the extraocular muscles are in a continuous process of cellular regeneration, due to these satellite cells. Surgical treatment of strabismus attempts to balance the forces generated by extraocular muscles. However, this procedure modifies the normal muscle dynamics and unavoidably causes scarring, incomitant gaze and, occasionally, secondarystrabismus. The need to discover pharmacological treatment for strabismus, which does not cause permanent muscle weakening, but has a longer lasting effect than botulinum toxin, has stimulated the scientific community to seek alternative substances. Recent studies haveverified that crotoxin was successful in inducing temporary paralysis in the superior rectus muscles of rabbits and that its action and effects were similar to those produced by botulinum toxin A.Purpose: To evaluate the effect of botulinum toxin A and crotoxin on satellite cell activation in the muscle fibers of superior rectus muscles of rabbits.Material and Methods: The superior rectus muscles in the right eyes of 29 male, albino, New Zealand rabbits were inoculated with different doses of botulinum toxin A or crotoxin. The contra-lateral superior rectus muscles in each rabbit were inoculated with the same volume of saline solution only. The animals were sacrificed either 12, 18 or 25 days after theinoculation. The eyes were enucleated, maintaining the superior rectus muscles intact. Subsequently, each muscle was prepared for immunohistochemical analysis, using satellite cell markers Myo D and PCNA. The positive nuclei, revealed by the markers in each 100myofibers, were counted.Results: The application of the botulinum toxin A and crotoxin triggered a more significant increase satellite cell activation and proliferation in right superior rectus muscles in rabbits when compared with a saline solution inoculation in the contralateral muscles. Greater cell activation was observed after crotoxin application, although, statistically, the difference in the effects of this activation between the botox and crotoxin groups was not significant. There was no statistically significant correlation between the dose applied and resulting cell activation in the botox and crotoxin groups. Similarly, no correlation was found between the volume of the applied substance and cell activation in the botox, crotoxin and control groups. Post-application survival time contributed to the increase in activated satellite cells in all groups. Histological examination revealed more accentuated disorganization in muscle fibre architecture and more evidence of regeneration in the crotoxin group.Conclusion: The observed increase in disorganization in the muscle structure together with more obvious signs of regeneration in the crotoxin group suggests a correlation with the increase in satellite cell activation. It may be concluded that the process of muscle-fibre regeneration after the crotoxin application is slower than that which occurs after the botulinum toxin A application, which may explain the longer lasting action of crotoxin.
Introdução: Quando ocorre uma lesão muscular, as células satélites tornam-se ativas, dividem-se e reparam as fibras lesadas ou formam novas miofibras. Ao contrário da musculatura esquelética, que é pós-mitótica, os músculos extrínsecos oculares apresentam-se em contínua renovação celular, devido às células satélites. O tratamento cirúrgico do estrabismo visa equilibrar as forças geradas pelos músculos oculares extrínsecos, porém compromete a dinâmica muscular normal e, inevitavelmente, provoca cicatrizes,incomitâncias e, ocasionalmente, estrabismos secundários. A necessidade de se descobrir um tratamento farmacológico para o estrabismo que não cause enfraquecimento muscular permanente, mas que tenha uma duração maior que a da toxina botulínica, estimula acomunidade científica a pesquisar novas substâncias. Estudos recentes verificaram que a crotoxina é capaz de induzir uma paralisia transitória em músculo reto superior de coelhos e que sua ação e seu efeito foram semelhantes aos da toxina botulínica do tipo A.Objetivo: Avaliar o efeito da toxina botulínica do tipo A e da crotoxina na ativação de células satélites das fibras musculares de músculos retos superiores de coelhos.Material e métodos: Os músculos retos superiores do olho direito de 29 coelhos machos albinos neozelandeses foram inoculados com toxina botulínica do tipo A, ou com crotoxina, em diferentes doses. Os músculos retos superiores contralaterais de cada coelho foraminoculados com solução salina em volume igual ao das toxinas. Os animais foram sacrificados 12, 18 e 25 dias após as aplicações. Os olhos foram enucleados, mantendo-se os músculos retos superiores intactos. Cada músculo foi preparado para análise imunoistoquímica, com marcadores de células satélites Myo D e PCNA. Foi realizada contagem dos núcleos corados pelos marcadores a cada cem miofibras.Resultados: A aplicação de toxina botulínica e de crotoxina provocou um aumento no número de células satélites ativadas e em proliferação nos músculos retos superiores dos coelhos. A inoculação de solução salina nos músculos contralaterais não causou aumento significativo. Uma maior ativação celular foi observada após a aplicação de crotoxina embora, estatisticamente, a diferença do efeito de ativação entre os grupos botox e crotoxina não tenha sido considerável. Nos grupos botox e crotoxina, não houve correlação estatisticamente significativa entre a dose e o aumento na ativação das células. Da mesma forma, não foiencontrada correlação entre o volume de substância aplicada e a ativação celular nos grupos botox, crotoxina e controle. O tempo de vida após a aplicação contribuiu para o aumento de células satélites ativadas em todos os grupos. No estudo histológico, o grupo crotoxina revelou acentuado desarranjo na arquitetura das fibras musculares e mais evidências de regeneração.Conclusão: A observação de maior desorganização na estrutura muscular e de sinais de regeneração mais evidentes no grupo crotoxina parece estar correlacionada ao aumento de células satélites ativadas. Supõe-se que o processo de regeneração das fibras musculares apósa aplicação da crotoxina seja mais lento que após a aplicação da toxina botulínica, o que explicaria a ação mais duradoura da crotoxina.

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AMARAL, Andréia Vitor Couto do. "Levobupivacaína, ropivacaína ou lidocaína na anestesia palpebral em equinos: avaliação da pressão intra-ocular, da produção lacrimal e da eficácia do bloqueio anestésico." Universidade Federal de Goiás, 2009. http://repositorio.bc.ufg.br/tede/handle/tde/1193.

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Corneal anesthesia is required in order to evaluate the intraocular pressure (IOP) and eyelid blockades may also be necessary, using local anesthetic agents in horses. The aim of this study was to evaluate the IOP and the corneal touch threshold (CTT) at the central area of the cornea, after eyelid blockades with anesthetic 0.75% ropivacaine, 0.75% levobupivacaine and 2% lidocaine. Nine adult female animals of undefined breed horses, which received 2.0 ml of anesthetic for supraorbitary blockade and 2.5 ml for auriculopalpebral blockagde. All animals were anesthetized with the three anesthetic drugs, with an interval period of seven days between drugs, performing a Latin square 3x3x3. The IOP and CTT were measured before and 10, 20, 40, 60, 80 and 100 minutes after the blockades. The PIO was maintained within the limits considered normal in all three anesthetic drug groups evaluated. After 10 minutes, there was significantly CTT values decrease for all three anesthetics. The recovery time of CTT was higher in 30 the animals anesthetized with lidocaine than those anesthetized with levobupivacaine and ropivacaine
Os agentes anestésicos locais possuem ampla utilização e aplicação na oftalmologia de grandes animais, uma vez que os eqüinos e os bovinos apresentam o músculo orbicular potente, exercendo vigoroso fechamento das pálpebras na presença de dor ou pela simples tentativa de manipulação pelo examinador. Sendo assim, os bloqueios palpebrais são requeridos desde a realização de exame clínico oftálmico de rotina a procedimentos cirúrgicos locais em cavalos. Nesse estudo, foram avaliados os efeitos de soluções anestésicas a base de cloridrato de ropivacaína a 0,75%, cloridrato de levobupivacaína a 0,75% e cloridrato de lidocaína a 2% na pressão intraocular (PIO), no limiar de sensibilidade ao toque corneal (LSTC), na produção lacrimal e na movimentação e sensibilidade palpebral em nove eqüinos, adultos, fêmeas, submetidas ao bloqueio auriculopalpebral e supraorbitário. A PIO e o LSTC foram mensurados antes e aos 10, 20, 40, 60, 80 e 100 minutos após os bloqueios palpebrais. Foi possível observar que a ropivacaína a 0,75% e a levobupivacaína a 0,75% acarretam em diminuição da pressão intra-ocular quando se comparada com a lidocaína a 2%, porém com flutuações dentro da faixa de PIO considerada normal para eqüinos. Verificou-se também que a ropivacaína e levobupivacaína diminuem de forma significativa LSTC, da área central da córnea, e o mantém em níveis que proporcionam anestesia corneal por até 100 minutos. A produção lacrimal foi mensurada utilizando-se o Teste Lacrimal de Schirmer 1 (STT-1) e Teste de Schirmer 2 (STT-2) antes dos bloqueios e o STT foi mensurado aos 20, 60 e 100 minutos após os bloqueios anestésicos palpebrais. Foi observado que valores de STT nos bloqueios palpebrais com ropivacaína a 0,75%, levobupivacaína a 0,75% e lidocaína a 2% foram significativamente maiores quando comparados ao STT-2 e que não houve diferença significativa entre STT-1 e STT, após bloqueio anestésico do auriculopalpebral e supra-orbitário, não sendo observadas também diferenças da produção lacrimal relativamente aos diferentes fármacos anestésicos. A movimentação e a sensibilidade palpebrais foram avaliadas utilizando os testes neurológicos de reflexos de ameaça e palpebrais Foi possível concluir que, a ropivacaína a 0,75% e a levobupivacaína a 0,75% promoveram semelhantes bloqueios motor e sensitivo, enquanto que, a lidocaína 2% determinou um rápido retorno da movimentação e da sensibilidade palpebral em cavalos submetidos aos bloqueios do supraorbitário e auriculopalpebral

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Moura, Christiane Montenegro Coimbra. "Investigações oftámicas em morcegos microquirópteros e levantamento dos diagnósticos histopatológicos em laboratório de patologia ocular animal = Ophthalmic investigations of microchiropteran bats and a survey of hinstopathological diagnostics in a comparative ophthalmology laboratory." reponame:Repositório Institucional da UFPR, 2015. http://hdl.handle.net/1884/46345.

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Orientador : Prof. Dr. Fabiano Montiani-Ferreira
Dissertação (mestrado) - Universidade Federal do Paraná, Setor de Ciências Agrárias, Programa de Pós-Graduação em Ciências Veterinárias. Defesa: Curitiba, 24/03/2015
Inclui referências : f. 18-19;72-74;75-79
Área de concentração : Ciências veterinárias
Resumo: A presente dissertação está dividida em quatro capítulos. O primeiro capítulo introduz brevemente o leitor à história natural dos morcegos, apresentando esses animais e diferenciando-os em megaquirópteros e microquirópteros, tendo em vista que este animal será abordado nos dois capítulos seguintes. O Capítulo 2 descreve a presença da espinha óptica do alisfenóide em duas espécies de microquirópteros. A referida estrutura anatômica havia sido descrita somente no morcego-das-frutas (Artibeus lituratus). Poucos são os dados disponíveis na literatura no que diz respeito à oftalmologia de morcegos. Assim, o terceiro capítulo apresenta valores para produção lacrimal, tonometria e comprimento horizontal da fenda palpebral para as espécies Artibeus lituratus e Anoura caudifer. Esses dados poderão servir de valores de referência para pesquisas futuras nessa ordem dos mamíferos. Já o Capítulo 4 apresenta o levantamento de casos diagnosticados histopatologicamente pelo Laboratório de Oftalmologia Comparada (LABOCO) da Universidade Federal do Paraná. Dentre eles estão bulbos oculares e pálpebras de cães, gatos, cavalos e diferentes espécies de animais selvagens. Palavras-chave: Oftalmologia comparada, morcegos, patologia ocular.
Abstract: The present study is divided in four chapters. The first one briefly introduces the reader to the natural history of bats, showing these animals and differentiating them in megachiroptera and microchiroptera, since bats will be adressed in the next two chapters. Chapter 2 describes the presence of optic spine of the alisphenoid bone in two species of microbats. This anatomic structure had only been described in the large fruit-eating bat (Artibeus lituratus). There are very few studies available in the literature concerning bat ophthalmology. Thus, the third chapter provides values for tear production, tonometry and measurement of the horizontal length of the palpebral fissure for two species of microbats: Artibeus lituratus and Anoura caudifer. These data may serve as reference values for future research in this order of mammals. Chapter 4 presents the survey of eye diseases histopathologically diagnosed by Comparative Ophthalmology Laboratory (LABOCO) of the Federal University of Paraná. These include eyeballs and eyelids of dogs, cats, horses and different species of wildlife. Key-words: Comparative ophthalmology, bats, ocular patology

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CUNHA, Cristiane Honorato. "A influ?ncia da abla??o unilateral do ped?nculo ocular e a reprodu??o do camar?o de ?gua doce Macrobrachium acanthurus (Wiegmann, 1836) em cativeiro." Universidade Federal Rural do Rio de Janeiro, 2008. https://tede.ufrrj.br/jspui/handle/jspui/2382.

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Macrobrachium acanthurus is the freshwater prawn species that is find in almost whole coastal rivers in Brazilian coast. This work was carried out to get information about reproductive aspects of Macrobrachium acanthurus in captivity and the influence on unilateral eyestalk ablation technique. 48 females and 24 males were captured in Sahy river at Mangaratiba/RJ and kept in adaptation for 15 days. Then, the animals carapace length and total length were measured. They were distributed into 20 liters aquariums, each of them with two males and four females. Two females in each aquarium were ablated. Abiotic factors such as pH, ammonia, nitrite and oxygen levels were checked weekly and the water temperature daily. Every day the occurrence of ovigerous females were checked in each aquarium. After three days incubating, the ovigerous females were separated until the larvae eclosion. And then, they were returned to the aquarium for a new phase of reproduction. The animals were fed with ration pellets and pieces of fish. The U test (Mann-Whitney) showed a significant difference among laying intervals between the ablated and non-ablated females. The Pearson correlation showed temperature influence on incubation period on non-ablated females, but on ablated females there was no dependency relationship. The t-test showed no significant difference on fertility, between ablated and non-ablated M. acanthurus.
Macrobrachium acanthurus ? uma esp?cie de camar?o de ?gua doce encontrado em quase todos os rios litor?neos da costa brasileira. Este trabalho foi realizado com o objetivo de obter informa??es sobre a influ?ncia da t?cnica de abla??o unilateral do ped?nculo ocular na reprodu??o de Macrobrachium acanthurus em cativeiro. Foram utilizados no experimento 48 f?meas e 24 machos, que foram coletados no Rio Sahy, Mangaratiba/RJ e foram mantidas durante 15 dias para a adapta??o. Posteriormente, os animais foram medidos em rela??o ao comprimento da carapa?a e comprimento total, distribu?dos na propor??o de dois machos para quatro f?meas em doze aqu?rios com capacidade de 20 litros. Das quatro f?meas de cada aqu?rio, duas foram abladas. Os fatores abi?ticos como o pH, am?nio, nitrito e oxig?nio dissolvido foram verificados semanalmente e a temperatura da ?gua diariamente. Todos os dias foram verificados a ocorr?ncia de exterioriza??o dos ovos em cada f?mea. As f?meas ov?geras ap?s tr?s dias de incuba??o foram individualizadas at? a eclos?o das larvas. Ap?s a eclos?o das larvas, as f?meas retornaram para o aqu?rio para uma nova fase de reprodu??o. Os animais foram alimentados com ra??o peletizada e peixe fresco. Atrav?s do teste U (Mann-Whitney) foi verificado que houve diferen?a significativa para o intervalo entre as desovas entre f?meas abladas e n?o abladas. Atrav?s da Correla??o de Pearson verificou-se que houve influ?ncia da temperatura no tempo de incuba??o nas f?meas n?o abladas, mas nas f?meas abladas n?o houve rela??o dependente. Atrav?s do teste t foi verificado que n?o houve diferen?a significativa para fertilidade entre as f?meas abladas e n?o abladas de M. acanthurus.

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Guo, Peiyi. "A Glia-Mediated Feedback Mechanism for the Termination of Drosophila Visual Response: A Dissertation." eScholarship@UMMS, 2010. https://escholarship.umassmed.edu/gsbs_diss/499.

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High temporal resolution of vision relies on the rapid kinetics of the photoresponse in the light-sensing photoreceptor neurons. It is well known that the rapid recovery of photoreceptor membrane potential at the end of light stimulation depends on timely deactivation of the visual transduction cascade within photoreceptors. Whether any extrinsic factor contributes to the termination speed of the photoresponse is unknown. In this thesis, using Drosophilaas a model system, I show that a feedback circuit mediated by both neurons and glia in the visual neuropile lamina is required for rapid repolarization of the photoreceptor at the end of the light response. In the first part of my thesis work, I provide evidence that lamina epithelial glia, the major glia in the visual neuropile, is involved in a retrograde regulation that is critical for rapid repolarization of the photoreceptor at the end of light stimulation. I identified the gene affected in a slrp (slow receptor potential) mutant that is defective in photoreceptor response termination, and found it needs to be expressed in both neurons and epithelial glia to rescue the mutant phenotype. The gene product SLRP, an ADAM (a disintegrin and metalloprotease) protein, is localized in a special structure of epithelial glia, gnarl, and is required for gnarl formation. This glial function of SLRP is independent of the metalloprotease activity. In the second part of my thesis work, I demonstrate that glutamatergic transmission from lamina intrinsic interneurons, the amacrine cells, to the epithelial glia is required for the rapid repolarization of photoreceptors at the end of the light response. From an RNAi-based screen, I identified a vesicular glutamate transporter (vGluT) in amacrine cells as an indispensable factor for the rapid repolarization of the photoreceptor, suggesting a critical role of glutamatergic transmission from amacrine cells in this retrograde regulation. Further, I found that loss of a glutamate-gated chloride channel GluCl phenocopies vGluT downregulation. Cell specific knockdown indicates that GluCl functions in both neurons and glia. In the lamina, a FLAG-tagged GluCl colocalized with the SLRP protein in the gnarl-like structures, and this localization pattern of GluCl depends on SLRP, suggesting that lamina epithelial glia receive glutamatergic input from amacrine cells through GluCl at the site of gnarl. Since the amacrine cell itself is innervated by photoreceptors, these observations suggest that a photoreceptor — amacrine cell — epithelial glia — photoreceptor feedback loop facilitates rapid repolarization of photoreceptors at the end of the light response. In summary, my thesis research has revealed a feedback regulation mechanism that helps to achieve rapid kinetics of photoreceptor response. This visual regulation contributes to the temporal resolution of the visual system, and may be important for vision during movement and for motion detection. In addition, this work may also advance our understanding of glial function, and change our concept about the effect of glutamatergic transmission.

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Koon, Alex C. "Autoregulatory and Paracrine Control of Synaptic and Behavioral Plasticity by Dual Modes of Octopaminergic Signaling: A Dissertation." eScholarship@UMMS, 2011. https://escholarship.umassmed.edu/gsbs_diss/572.

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Synaptic plasticity—the ability of a synapse to change—is fundamental to basic brain function and behavioral adaptation. Studying the mechanisms of synaptic plasticity benefits our understanding of the formation of neuronal connections and circuitry, which has great implications in the field of learning and memory and the studies of numerous human diseases. The Drosophila larval neuromuscular junction (NMJ) system is a powerful system for studying synaptic plasticity. The NMJ consists of at least two different types of motorneurons innervating the body wall muscles. Type I motorneurons controls muscle contraction using glutamate as the neurotransmitter, while type II are modulatory neurons that contain octopamine. Octopamine is a potent modulator of behavior in invertebrates. Nevertheless, its function at the synapse is poorly understood. In my thesis research, I investigated the role of octopamine in synaptic plasticity using the Drosophila NMJ system. Preliminary observations indicate that increased larval locomotion during starvation results in an increase of filopodia-like structures at type II terminals. These structures, which we termed as “synaptopods” in our previous studies, contain synaptic proteins and can mature into type II synapses. I demonstrated that this outgrowth of type II terminals is dependent on activity and octopamine. Mutations and genetic manipulations affecting the production of octopamine decrease synaptopods, whereas increase of type II activity or exogenous application of octopamine increase synaptopods. Interestingly, I found that the type II octopaminergic neurons have an absolute dependence on activity for their innervation of the muscles. Blocking activity in these neurons throughout development results in no type II synapses at the NMJ, whereas blocking activity after the formation of synapses results in gradual degradation of type II terminals. Next, I examined the autoregulatory mechanism underlying the octopamine-induced synaptic growth in octopaminergic neurons. I discovered that this positive-feedback mechanism depends on an octopamine autoreceptor, Octß2R. This receptor in turn activates a cAMP- and CREB-dependent pathway that is required in the octopamine-induction of synaptopods. Furthermore, I demonstrated that this octopaminergic autoregulatory mechanism is necessary for the larva to properly increase its locomotor activity during starvation. Thirdly, I investigated the possibility that type II innervation might regulate type I synaptic growth through octopamine. We found that ablation, blocking of type II activity, or the absence of octopamine results in reduced type I outgrowth, and this paracrine signaling is mediated by Octß2R which is also present in type I motorneurons. Lastly, the function of another octopamine receptor, Octß1R, was examined. In contrast to Octß2R, Octß1R is inhibitory to synaptic growth. I demonstrated that the inhibitory effect of this receptor is likely accomplished through the inhibitory G-protein Goα. Similar to Octß2R, Octß1R also regulates the synaptic growth of both type I and type II motorneurons in a cell-autonomous manner. The inhibitory function of this receptor potentially breaks the positive feedback loop mediated by Octß2R, allowing the animal to reset its neurons when the environment is favorable. In summary, the research presented in this thesis has unraveled both autoregulatory and paracrine mechanisms in which octopamine modulates synaptic and behavior plasticity through excitatory and inhibitory receptors.

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Tikh, Eugene I. "Regulation of Contractility by Adenosine A₁ and A_2A Receptors in the Murine Heart: Role of Protein Phosphatase 2A: A Dissertation." eScholarship@UMMS, 2006. https://escholarship.umassmed.edu/gsbs_diss/130.

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Adenosine is a nucleoside that plays an important role in the regulation of contractility in the heart. Adenosine receptors are G-protein coupled and those implicated in regulation of contractility are presumed to act via modulating the activity of adenylyl cyclase and cAMP content of cardiomyocytes. Adenosine A1 receptors (A1R) reduce the contractile response of the myocardium to β-adrenergic stimulation. This is known as anti adrenergic action. The A2A adenosine receptor (A2AR) has the opposite effect of increasing contractile responsiveness of the myocardium. The A2AR also appears to attenuate the effects of A1R. The effects of these receptors have been primarily studied in the rat heart and with the utilization of cardiomyocyte preparations. With the increasing use of receptor knockout murine models and murine models of various pathological states, it is of importance to comprehensively study the effects of adenosine receptors on regulation of contractility in the murine heart. The following studies examine the adenosinergic regulation of myocardial contractility in isolated murine hearts. In addition, adenosinergic control of contractility is examined in hearts isolated from A2AR knockout animals. Responses to adenosinergic stimulation in murine isolated hearts are found to be comparable to those observed in the rat, with A1R exhibiting an anti adrenergic action and A2AR conversely enhancing contractility. A significant part of the A2AR effect was found to occur via inhibition of the A1R antiadrenergic action. A part of the anti adrenergic action of A1R has previously been shown to be the result of protein phosphatase 2A activation and localization to membranes. Additional experiments in the present study examine the effect of adenosinergic signaling on PP2A in myocardial extracts from wild type and A2AR knockout hearts. A2AR activation was found to decrease the activity of PP2A and enhance localization of the active enzyme to the cytosol; away from its presumed sites of action. In the A2AR knockout the response to A1R activation was enhanced compared with the wild type and basal PP2A activity was reduced. It is concluded that A2AR modulation of PP2A activity may account for the attenuation of the A1R effect by A2AR observed in the contractile studies.

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Henninger, Nils. "Inhibiting Axon Degeneration in a Mouse Model of Acute Brain Injury Through Deletion of Sarm1." eScholarship@UMMS, 2017. http://escholarship.umassmed.edu/gsbs_diss/900.

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Traumatic brain injury (TBI) is a leading cause of disability worldwide. Annually, 150 to 200/1,000,000 people become disabled as a result of brain trauma. Axonal degeneration is a critical, early event following TBI of all severities but whether axon degeneration is a driver of TBI remains unclear. Molecular pathways underlying the pathology of TBI have not been defined and there is no efficacious treatment for TBI. Despite this significant societal impact, surprisingly little is known about the molecular mechanisms that actively drive axon degeneration in any context and particularly following TBI. Although severe brain injury may cause immediate disruption of axons (primary axotomy), it is now recognized that the most frequent form of traumatic axonal injury (TAI) is mediated by a cascade of events that ultimately result in secondary axonal disconnection (secondary axotomy) within hours to days. Proposed mechanisms include immediate post-traumatic cytoskeletal destabilization as a direct result of mechanical breakage of microtubules, as well as catastrophic local calcium dysregulation resulting in microtubule depolymerization, impaired axonal transport, unmitigated accumulation of cargoes, local axonal swelling, and finally disconnection. The portion of the axon that is distal to the axotomy site remains initially morphologically intact. However, it undergoes sudden rapid fragmentation along its full distal length ~72 h after the original axotomy, a process termed Wallerian degeneration. Remarkably, mice mutant for the Wallerian degeneration slow (Wlds) protein exhibit ~tenfold (for 2–3 weeks) suppressed Wallerian degeneration. Yet, pharmacological replication of the Wlds mechanism has proven difficult. Further, no one has studied whether Wlds protects from TAI. Lastly, owing to Wlds presumed gain-of-function and its absence in wild-type animals, direct evidence in support of a putative endogenous axon death signaling pathway is lacking, which is critical to identify original treatment targets and the development of viable therapeutic approaches. Novel insight into the pathophysiology of Wallerian degeneration was gained by the discovery that mutant Drosophila flies lacking dSarm (sterile a/Armadillo/Toll-Interleukin receptor homology domain protein) cell-autonomously recapitulated the Wlds phenotype. The pro-degenerative function of the dSarm gene (and its mouse homolog Sarm1) is widespread in mammals as shown by in vitro protection of superior cervical ganglion, dorsal root ganglion, and cortical neuron axons, as well as remarkable in-vivo long-term survival (>2 weeks) of transected sciatic mouse Sarm1 null axons. Although the molecular mechanism of function remains to be clarified, its discovery provides direct evidence that Sarm1 is the first endogenous gene required for Wallerian degeneration, driving a highly conserved genetic axon death program. The central goals of this thesis were to determine (1) whether post-traumatic axonal integrity is preserved in mice lacking Sarm1, and (2) whether loss of Sarm1 is associated with improved functional outcome after TBI. I show that mice lacking the mouse Toll receptor adaptor Sarm1 gene demonstrate multiple improved TBI-associated phenotypes after injury in a closed-head mild TBI model. Sarm1-/- mice developed fewer beta amyloid precursor protein (βAPP) aggregates in axons of the corpus callosum after TBI as compared to Sarm1+/+ mice. Furthermore, mice lacking Sarm1 had reduced plasma concentrations of the phosphorylated axonal neurofilament subunit H, indicating that axonal integrity is maintained after TBI. Strikingly, whereas wild type mice exhibited a number of behavioral deficits after TBI, I observed a strong, early preservation of neurological function in Sarm1-/- animals. Finally, using in vivo proton magnetic resonance spectroscopy, I found tissue signatures consistent with substantially preserved neuronal energy metabolism in Sarm1-/- mice compared to controls immediately following TBI. My results indicate that the Sarm1-mediated prodegenerative pathway promotes pathogenesis in TBI and suggest that anti-Sarm1 therapeutics are a viable approach for preserving neurological function after TBI.

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Lai, Li Ju, and 賴麗如. "Studies on mechanism of ocular injury by chemical burn and gene therapy in animal model." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/23384034201084661808.

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博士
長庚大學
臨床醫學研究所
101
The corneal clarity and avascularity are important for the proper optical performance of the cornea. Chemical burn on the ocular surface usually causes abundant cornea inflammation and neovascularization (NV). Corneal NV is a severe debilitating condition that results in the loss of immune privilege of the cornea and in visual impairment. The goal for ophthalmologists is to understand the mechanism of tissue response during chemical burn, and to find the optimal treatment. This study evaluated the pathophysiology of cornea and ocular surface after chemical burn by formaldehyde (FA) and silver nitrate (AgNO3) and the treatment by gene therapy using recombinant adeno-associated virus carrying endostatin and angiostatin genes. The molecular basis of cornea avascularity during chemical burn and the role of anti-angiogenic factors in the corneal neovascularization were evaluated. FA with different concentrations and duration was used for chemical burn experiments on the ex vivo cultured rabbit cornea epithelium and New Zealand rabbits in vivo. Cell survival and MTT cell activity were evaluated. Mitochondria activity and flow cytometry were evaluated to show the cornea response to chemical toxicity. Western blottings were used to determine the ERK and JNK activations at 2 months after treatment. Angiogensis was generated by silver nitrate on mice and rat cornea. Gene transfer by subconjunctival injection with recombinant adeno-associated virus carrying green fluorescence protein, endostatin or angiostatin was evaluated for their effects on neovascularization. The percentage of neovascularization area was measured and compared with the controlled group. The expression of endostatin was detected by immunohistochemistry of CD31 and endostatin. The cornea damage by FA concentration higher than 5 ppm was found to be irreversible. JNK activation in vivo in conjunctiva tissue could be detected even two months after a 5 min transient exposure to FA. Mitochondria activity was decreased and showed dose-dependent to FA. Apoptosis and cell cycle arrest at sub-G1 phase could be observed in FA treated cells. Subconjunctival injection of rAAV-angiostatin and rAAV-endostatin successfully suppressed the corneal neovascularization induced by silver nitrate chemical burns. FITC-conA angiography analysis indicated a significant suppression of neovascularization. The area of suppression of corneal neovascularization correlated to the sites of virus injection. Subconjunctival injection of rAAV-angiostatin led to the suppression of the corneal neovascularization during the whole 12 weeks of our observation, and the rAAV-GFP could be stably observed in the subconjunctival cells for more than 6 months. Following corneal injury, wound healing often shows permanent scarring and proceeds without neovascularization. However, cornea neovascularization may be induced during severe inflammatory, infectious, degenerative, and traumatic corneal disorders. Subconjunctival injection of rAAV-endostatin or rAAV-angiostatin provides a safe treatment modality in the treatment of cornea NV induced by ocular surface disorder.

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28

"Pathogenesis of retinoic acid-induced developmental ocular defects studied using mouse models." Thesis, 2009. http://library.cuhk.edu.hk/record=b6074726.

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As exogenously administered RA suppressed the expression of the RA synthesizing enzymes, further investigation on whether this would lead to deficiency in endogenous RA concentrations was conducted. Results showed that exogenously administered RA significantly reduced the endogenous RA level in the head region with C57 embryos showing a greater reduction than ICR embryos.
In addition, detailed morphological and histological studies were conducted to determine if RA treatment caused early embryonic changes with strain difference. When compared with ICR embryos, C57 embryos exhibited more pronounced responses to RA, including developmental retardation, underdevelopment of the anterior neural plate and absence of or smaller optic pit/optic vesicle formation. However, RA treatment did not cause abnormal apoptosis in the early stages in both strains.
Since the teratogenic effect of RA is highly developmental stage-dependent, it is possible that there is a difference in the developmental stage between these 2 mouse strains at the time of RA injection. Indeed, it was found that the developmental stage of ICR embryos was approximately 6 hours ahead of C57 embryos. However, the role that this factor plays in the differential strain susceptibility to RA can be excluded since C57 fetuses were still 3 times more susceptible to developing anophthalmia/microphthalmia than ICR fetuses that were subject to RA treatment at equivalent developmental stages. Comparison of susceptibility to RA-induced anophthalmia/microphthalmia was also made among heterozygous fetuses obtained from reciprocal matings between C57 and ICR male and female mice, and those in homozygous ICR and C57 fetuses. Results showed that the C57 strain has conferred both genetic predisposition and maternal effects in increasing the embryo's susceptibility to RA-induced ocular defects.
Since the type of RA-induced ocular defects mimic those that developed in Raldh2 null mutant embryos, the effect of RA treatment on the expression of RA synthesizing enzymes, Raldh2 and Raldh3, and the RA-inducible gene Cyp26a1, as well as some early eye development genes were examined. Exogenously administered RA reduced the mRNA expression levels of Raldh2, Raldh3 and Cyp26a1 in the head region, with C57 embryos showing a greater reduction than ICR embryos.
Taken together, results of this thesis suggest that there is a strain difference in susceptibility to RA-induced ocular defects in which exogenously applied RA suppresses the expression of RA synthesizing enzymes and leads to endogenous RA deficiency. This finding may shed light on understanding why both excess and deficiency of RA can lead to similar types of ocular defects.
To determine if there are strain differences in the susceptibility to RA-induced ocular defects, two mouse strains were used. They are C57BL/6J (C57), mice that spontaneously develop ocular defects and ICR mice, which are not prone to developing ocular defects. Detailed time and dose response studies were conducted and eye defects were examined in near-term fetuses. C57 fetuses were found to be significantly more susceptible to RA-induced anophthalmia/microphthalmia than ICR fetuses.
Vitamin A (retinol) and its most active metabolite, all- trans retinoic acid (RA) is essential for vision in the adult and for eye development in the embryo. It is well documented that in humans, excess intake or deficiency of vitamin A or RA is associated with congenital ocular defects such as microphthalmia. However, the underlying mechanism remains unclear. The aim of this study is to examine the pathogenic mechanism of RA-induced developmental ocular defects.
Lau, Wing Sze Josephine.
Source: Dissertation Abstracts International, Volume: 71-01, Section: B, page: 0240.
Thesis (Ph.D.)--Chinese University of Hong Kong, 2009.
Includes bibliographical references (leaves 186-211).
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.
Abstracts in English and Chinese.

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29

McCanna, David. "Development of Sensitive In Vitro Assays to Assess the Ocular Toxicity Potential of Chemicals and Ophthalmic Products." Thesis, 2009. http://hdl.handle.net/10012/4338.

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The utilization of in vitro tests with a tiered testing strategy for detection of mild ocular irritants can reduce the use of animals for testing, provide mechanistic data on toxic effects, and reduce the uncertainty associated with dose selection for clinical trials. The first section of this thesis describes how in vitro methods can be used to improve the prediction of the toxicity of chemicals and ophthalmic products. The proper utilization of in vitro methods can accurately predict toxic threshold levels and reduce animal use in product development. Sections two, three and four describe the development of new sensitive in vitro methods for predicting ocular toxicity. Maintaining the barrier function of the cornea is critical for the prevention of the penetration of infections microorganisms and irritating chemicals into the eye. Chapter 2 describes the development of a method for assessing the effects of chemicals on tight junctions using a human corneal epithelial and canine kidney epithelial cell line. In Chapter 3 a method that uses a primary organ culture for assessing single instillation and multiple instillation toxic effects is described. The ScanTox system was shown to be an ideal system to monitor the toxic effects over time as multiple readings can be taken of treated bovine lenses using the nondestructive method of assessing for the lens optical quality. Confirmations of toxic effects were made with the utilization of the viability dye alamarBlue. Chapter 4 describes the development of sensitive in vitro assays for detecting ocular toxicity by measuring the effects of chemicals on the mitochondrial integrity of bovine cornea, bovine lens epithelium and corneal epithelial cells, using fluorescent dyes. The goal of this research was to develop an in vitro test battery that can be used to accurately predict the ocular toxicity of new chemicals and ophthalmic formulations. By comparing the toxicity seen in vivo animals and humans with the toxicity response in these new in vitro methods, it was demonstrated that these in vitro methods can be utilized in a tiered testing strategy in the development of new chemicals and ophthalmic formulations.

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