Global ETD Search

11	Relação entre biomarcadores inflamatórios, de adesão celular, de estresse oxidativo, de lesão endotelial, remodelamento tecidual e vascular e os diferentes estágios da doença venosa crônica primária (classes clínicas CEAP C0a, C2, C3, C4) / Relationship between biomarkers of inflammation, cell adhesion, oxidative stress, endothelial cell damage, vascular and tissue remodeling and the different stages of primary chronic venous disease (CEAP clinical classes C0a, C2, C3, C4) Maria das Graças Coelho de Souza 20 August 2013 (has links) A doença venosa crônica (DVC) é uma desordem complexa que compreende sinais e sintomas que variam das telangiectasias às úlceras ativas. A DVC é classificada de acordo com aspectos clínicos, etiológicos, anatômicos e fisiopatológicos (CEAP) em sete classes variando de C0 à C6. A principal causa da DVC é a hipertensão venosa que altera o fluxo venoso e, consequentemente, a força de cisalhamento que induz alterações fenotípicas nas células endoteliais que passam a expressar mediadores pró-inflamatórios e pró-trombóticos, que levam à adesão de leucócitos, ao aumento do estresse oxidativo, da permeabilidade vascular e do dano endotelial e ao remodelamento tecidual e vascular.Em virtude dos inúmeros mecanismos e da diversidade de moléculas envolvidas na patogênese e progressão da DVC, é essencial conhecer a interação entre elas e também saber quais são as moléculas (biomarcadores) que se correlacionam positivamente ou negativamente com a gravidade da doença. Foram avaliados os níveis de Interleucina-6 (IL-6), sL-selectina, sE-selectina, sP-selectina, molécula de adesão intercelular-1solúvel (sICAM-1), molécula de adesão das células vasculares-1 solúvel (sVCAM-1), ativador tecidual do plasminogênio (tPA), atividade do inibidor do ativador do plasminogênio-1 (PAI-1), trombomodulina solúvel (sTM), fator de von Willebrand (vWF), metaloproteinase de matriz (MMP)-2, MMP-3, MMP-9, inibidor tecidual das MMPs -1 (TIMP-1), angiopoietina-1 e -2, sTie-2 e s-Endoglina e fator de crescimento do endotélio vascular (VEGF) no sangue coletado da veia braquial de 173 mulheres com DVC primária divididas em grupos C2, C3, C4 e C4 menopausadas (C4m) e de 18 voluntárias saudáveis (grupo C0a). Foram também analisados os níveis urinários de ent-prostaglandina F2α nesses grupos. Não foram encontradas diferenças estatisticamente significativas com relação às concentrações sanguíneas e urinárias de sE-selectina, sP-selectina, sICAM-1, atividade de PAI-1, MMP-3, razão TIMP-1/MMP-3, angiopoietin-2, razão angiopoietina-1/angiopoietina-2, s-Endoglina e ent-prostaglandina F2α entre os grupos estudados, possivelmente devido à alta variabilidade na concentração desses biomarcadores entre as participantes do mesmo grupo. Entretanto, as concentrações sanguíneas de IL-6 sL-selectina, sVCAM-1, tPA, vWF, sTM, MMP2, MMP-9, TIMP-1, razão TIMP-1/MMP-2, razão TIMP-1/MMP-9, angiopoietina-1 e VEGF foram estatisticamente diferentes entre os grupos. Não foi identificado nenhum biomarcador que se correlacionasse diretamente ou inversamente com a progressão da DVC, provavelmente devido à diversidade de fatores envolvidos e à complexa interação entre eles durante o curso da doença. / Chronic Venous Disease (CVD) is a complex disorder, which encompasses signs and symptoms that vary from telangiectasias to active ulcers. The CVD is classified according Clinical, Etiologic, Anatomical and Pathophysiological (CEAP) aspects into seven classes varying from C0 to C6. The main cause of CVD is venous hypertension, which alters venous flow and consequently, shear stress. Abnormal shear stress induces phenotypic changes in endothelial cells that start to express pro-inflammatory and pro-thrombotic mediators that lead to leukocyte adhesion, oxidative stress, increased vascular permeability and endothelial cell damage and tissue and vascular remodeling. Due to several mechanisms and the diversity of molecules involved in the pathogenesis and progression of CVD, is essential to know the interplay between them and which are the molecules (biomarkers) that correlate positively and negatively with the severity of the disease. We investigated the levels of interleukin-6 (IL-6), sL-selectin, sE-selectin, sP-selectin, soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1), tissue plasminogen activator (tPA), plasminogen activator inhibitor-1 (PAI-1) activity, soluble thrombomodulin (sTM), von Willebrand factor (vWf), matrix metalloproteinase (MMP)-2, MMP-3, MMP-9, tissue inhibitor of metaloproteinases-1 (TIMP-1), angiopoietin-1 and -2, sTie-2, s-Endoglin, vascular endothelial growth factor (VEGF) in the blood taken from the brachial vein of 173 patients with primary CVD divided into C2, C3, C4 and menopaused C4 (C4m) groups and 18 healthy volunteers (C0a group).We also investigated the urinary levels of ent-prostaglandin F2α in these groups. There was no statistically significant difference between groups with respect to blood or urinary levels of sE-selectin, sP-selectin, sICAM-1, PAI-1 activity, MMP-3, TIMP-1/MMP-3 ratio, angiopoietin-2, angiopoietin-1/angiopoietin-2 ratio, s-Endoglin and ent-prostaglandin F2α, likely due to the high variability of these biomarkers concentration among participants within the same group. However, blood levels of IL-6, sL-selectin, sVCAM-1, tPA, vWF, sTM, MMP-2, MMP-9, TIMP-1, TIMP-1/MMP-2 ratio, TIMP-1/MMP-9 ratio, angiopoietin-1 and VEGF were statistically different between groups. It was not identified any biomarker that correlated directly or inversely with the progression of CVD, probably due to the diversity of factors involved and the complex interplay between them in the course of the disease. Inflamação Veias varicosas Lesão endotelial Remodelamento tecidual Remodelamento vascular Varicose veins Inflammation Endothelial cell damage Tissue remodeling Vascular remodeling FISIOLOGIA
12	Relação entre biomarcadores inflamatórios, de adesão celular, de estresse oxidativo, de lesão endotelial, remodelamento tecidual e vascular e os diferentes estágios da doença venosa crônica primária (classes clínicas CEAP C0a, C2, C3, C4) / Relationship between biomarkers of inflammation, cell adhesion, oxidative stress, endothelial cell damage, vascular and tissue remodeling and the different stages of primary chronic venous disease (CEAP clinical classes C0a, C2, C3, C4) Maria das Graças Coelho de Souza 20 August 2013 (has links) A doença venosa crônica (DVC) é uma desordem complexa que compreende sinais e sintomas que variam das telangiectasias às úlceras ativas. A DVC é classificada de acordo com aspectos clínicos, etiológicos, anatômicos e fisiopatológicos (CEAP) em sete classes variando de C0 à C6. A principal causa da DVC é a hipertensão venosa que altera o fluxo venoso e, consequentemente, a força de cisalhamento que induz alterações fenotípicas nas células endoteliais que passam a expressar mediadores pró-inflamatórios e pró-trombóticos, que levam à adesão de leucócitos, ao aumento do estresse oxidativo, da permeabilidade vascular e do dano endotelial e ao remodelamento tecidual e vascular.Em virtude dos inúmeros mecanismos e da diversidade de moléculas envolvidas na patogênese e progressão da DVC, é essencial conhecer a interação entre elas e também saber quais são as moléculas (biomarcadores) que se correlacionam positivamente ou negativamente com a gravidade da doença. Foram avaliados os níveis de Interleucina-6 (IL-6), sL-selectina, sE-selectina, sP-selectina, molécula de adesão intercelular-1solúvel (sICAM-1), molécula de adesão das células vasculares-1 solúvel (sVCAM-1), ativador tecidual do plasminogênio (tPA), atividade do inibidor do ativador do plasminogênio-1 (PAI-1), trombomodulina solúvel (sTM), fator de von Willebrand (vWF), metaloproteinase de matriz (MMP)-2, MMP-3, MMP-9, inibidor tecidual das MMPs -1 (TIMP-1), angiopoietina-1 e -2, sTie-2 e s-Endoglina e fator de crescimento do endotélio vascular (VEGF) no sangue coletado da veia braquial de 173 mulheres com DVC primária divididas em grupos C2, C3, C4 e C4 menopausadas (C4m) e de 18 voluntárias saudáveis (grupo C0a). Foram também analisados os níveis urinários de ent-prostaglandina F2α nesses grupos. Não foram encontradas diferenças estatisticamente significativas com relação às concentrações sanguíneas e urinárias de sE-selectina, sP-selectina, sICAM-1, atividade de PAI-1, MMP-3, razão TIMP-1/MMP-3, angiopoietin-2, razão angiopoietina-1/angiopoietina-2, s-Endoglina e ent-prostaglandina F2α entre os grupos estudados, possivelmente devido à alta variabilidade na concentração desses biomarcadores entre as participantes do mesmo grupo. Entretanto, as concentrações sanguíneas de IL-6 sL-selectina, sVCAM-1, tPA, vWF, sTM, MMP2, MMP-9, TIMP-1, razão TIMP-1/MMP-2, razão TIMP-1/MMP-9, angiopoietina-1 e VEGF foram estatisticamente diferentes entre os grupos. Não foi identificado nenhum biomarcador que se correlacionasse diretamente ou inversamente com a progressão da DVC, provavelmente devido à diversidade de fatores envolvidos e à complexa interação entre eles durante o curso da doença. / Chronic Venous Disease (CVD) is a complex disorder, which encompasses signs and symptoms that vary from telangiectasias to active ulcers. The CVD is classified according Clinical, Etiologic, Anatomical and Pathophysiological (CEAP) aspects into seven classes varying from C0 to C6. The main cause of CVD is venous hypertension, which alters venous flow and consequently, shear stress. Abnormal shear stress induces phenotypic changes in endothelial cells that start to express pro-inflammatory and pro-thrombotic mediators that lead to leukocyte adhesion, oxidative stress, increased vascular permeability and endothelial cell damage and tissue and vascular remodeling. Due to several mechanisms and the diversity of molecules involved in the pathogenesis and progression of CVD, is essential to know the interplay between them and which are the molecules (biomarkers) that correlate positively and negatively with the severity of the disease. We investigated the levels of interleukin-6 (IL-6), sL-selectin, sE-selectin, sP-selectin, soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1), tissue plasminogen activator (tPA), plasminogen activator inhibitor-1 (PAI-1) activity, soluble thrombomodulin (sTM), von Willebrand factor (vWf), matrix metalloproteinase (MMP)-2, MMP-3, MMP-9, tissue inhibitor of metaloproteinases-1 (TIMP-1), angiopoietin-1 and -2, sTie-2, s-Endoglin, vascular endothelial growth factor (VEGF) in the blood taken from the brachial vein of 173 patients with primary CVD divided into C2, C3, C4 and menopaused C4 (C4m) groups and 18 healthy volunteers (C0a group).We also investigated the urinary levels of ent-prostaglandin F2α in these groups. There was no statistically significant difference between groups with respect to blood or urinary levels of sE-selectin, sP-selectin, sICAM-1, PAI-1 activity, MMP-3, TIMP-1/MMP-3 ratio, angiopoietin-2, angiopoietin-1/angiopoietin-2 ratio, s-Endoglin and ent-prostaglandin F2α, likely due to the high variability of these biomarkers concentration among participants within the same group. However, blood levels of IL-6, sL-selectin, sVCAM-1, tPA, vWF, sTM, MMP-2, MMP-9, TIMP-1, TIMP-1/MMP-2 ratio, TIMP-1/MMP-9 ratio, angiopoietin-1 and VEGF were statistically different between groups. It was not identified any biomarker that correlated directly or inversely with the progression of CVD, probably due to the diversity of factors involved and the complex interplay between them in the course of the disease. Inflamação Veias varicosas Lesão endotelial Remodelamento tecidual Remodelamento vascular Varicose veins Inflammation Endothelial cell damage Tissue remodeling Vascular remodeling FISIOLOGIA
13	Caracterização das propriedades antioxidantes, hipoglicemiantes e neuroprotetoras da erva mate em diferentes modelos Lima, Maria Eduarda de Lima 04 August 2017 (has links) Submitted by Marcos Anselmo (marcos.anselmo@unipampa.edu.br) on 2017-10-09T19:14:17Z No. of bitstreams: 1 MARIA EDUARDA DE LIMA.pdf: 3141919 bytes, checksum: f33f081cbf3931d572940d623c8c2074 (MD5) / Approved for entry into archive by Marcos Anselmo (marcos.anselmo@unipampa.edu.br) on 2017-10-09T19:14:51Z (GMT) No. of bitstreams: 1 MARIA EDUARDA DE LIMA.pdf: 3141919 bytes, checksum: f33f081cbf3931d572940d623c8c2074 (MD5) / Made available in DSpace on 2017-10-09T19:14:52Z (GMT). No. of bitstreams: 1 MARIA EDUARDA DE LIMA.pdf: 3141919 bytes, checksum: f33f081cbf3931d572940d623c8c2074 (MD5) Previous issue date: 2017-08-04 / A erva mate é o produto do processamento de folhas secas e moídas de uma espécie arbórea, conhecida como Ilex paraguariensis. A apresentação comercial da erva-mate é utilizada no preparo de uma bebida tradicional, muito consumida na América do Sul. Dados da literatura tem comprovado uma diversidade de efeitos benéficos da erva-mate, principalmente o antioxidante. Sabe-se que uma grande quantidade de patologias apresenta o estresse oxidativo como um dos seus mecanismos nocivos, desta maneira, a busca por compostos naturais que possam balancear tais situações foi intensificada nos últimos anos. Considerando os aspectos mencionados, o objetivo principal do presente estudo foi avaliar os possíveis efeitos protetores do extrato de Ilex paraguariensis em diferentes perspectivas com ênfase no estresse oxidativo. Inicialmente, foi realizada a caraterização do extrato por HPLC, seguido por uma comparação in vitro em sinaptossomas, do extrato (200 mg/mL) com o seu composto majoritário, ácido clorogênico CGA (2 mg/mL), quanto a produção de ROS, peroxidação de lipídios, função mitocondrial por MTT e a razão GSH/GSSG. Por conseguinte, foi realizada a avaliação in vivo, onde ratos Wistar machos (300-330 g) foram submetidos a estresse por restrição de movimentos, associado a outros estímulos estressantes, por 21 dias, 6h por dia (crônico) e tratados, por via oral, concomitantemente com extrato (200 mg/mL) ou CGA (2 mg/mL) e foram analisados parâmetros comportamentais de atividade locomotora e ansiedade, bem como, aspectos de dano celular, em córtex, hipocampo e estriado. Por fim, em um modelo de camundongos diabéticos, induzido com estreptozotocina (100 mg/kg), foram verificados os efeitos do extrato de erva mate (850 mg/kg), por via oral, sobre os níveis de glicose, neuropatia diabética e marcadores de estresse oxidativo, em rim, fígado e cérebro. O extrato de erva mate mostrou-se mais efetivo que o ácido clorogênico na proteção do dano oxidativo em sinaptossomas, reduzindo a formação de ROS, peroxidação de lipídios e depleção de glutationa, fatos que podem explicar o efeito do extrato em prevenir a disfunção mitocondrial avaliada. Da mesma maneira, no modelo de estresse por restrição de movimentos, o extrato de erva mate foi mais efetivo que o ácido clorogênico em prevenir as alterações comportamentais dos animais. O grupo que recebeu o extrato como tratamento, apresentou atividade locomotora igual ou superior a do grupo controle. Os animais tratados com extrato também se mostraram menos ansiosos que os do grupo estressado que não recebeu tratamento. Além disso, o extrato exibiu efeito de proteção do dano celular de córtex, hipocampo e estriado, pois os animais tratados apresentaram um maior número de células viáveis nesses tecidos. Com relação aos efeitos do extrato no modelo induzido de diabetes, verificou-se que a erva mate possui atividade de proteção ao estresse oxidativo envolvido na patogênese dessa patologia, além de reduzir de maneira significativa o nível glicêmico dos animais e apresentar efeito protetor à neuropatia diabética. Com base nos resultados encontrados, é possível dizer que, de modo geral, a erva mate atua na proteção de diferentes aspectos do estresse oxidativo devido ao sinergismo dos seus componentes, tendo em vista que o ácido clorogênico isolado não apresentou efeito protetor igual ou superior ao do extrato. Através do seu efeito antioxidante, apresenta benefícios à redução dos danos causados pela hiperglicemia crônica no diabetes mellitus e também, na modulação de efeitos neuroprotetores e função mitocondrial. / Yerba mate is the product of the processing of dried and ground leaves of a tree species, known as Ilex paraguariensis. The commercial presentation of yerba mate is used in the preparation of a traditional drink, widely consumed in South America. Data from the literature has proven a variety of beneficial effects of yerba mate, especially the antioxidant. It is known that a great number of pathologies present oxidative stress as one of its harmful mechanisms, in this way, the search for natural compounds that can balance such situations has intensified in recent years. Considering the mentioned aspects, the main objective of the present study was evaluate the possible protective effects of Ilex paraguariensis extract in different perspectives with emphasis on oxidative stress. Initially, was made the characterization of HPLC extract, followed by an in vitro comparison in synaptosomes, of the extract (200 mg / mL) with its major compound, chlorogenic acid CGA (2 mg / mL) in ROS formation, lipid peroxidation, mitochondrial function by MTT and the GSH / GSSG ratio. Therefore, in vivo evaluation was performed, where male Wistar rats (300-330 g) underwent movement restriction stress associated with other stress stimuli for 21 days, 6 hours per day (chronic) and treated with extract (200 mg / mL) or CGA (2 mg / mL) and behavioral parameters of locomotor activity and anxiety were analyzed, as well as aspects of cellular damage in the cortex, hippocampus and striatum. Finally, in a model of diabetic mice, induced with streptozotocin (100 mg / kg), were verified the effects of yerba mate extract (850 mg / kg) on glucose levels, diabetic neuropathy and markers Of oxidative stress, in kidney, liver and brain. The yerba mate extract was shown to be more effective than chlorogenic acid in the protection of oxidative damage in synaptosomes, by reducing ROS formation, lipid peroxidation and glutathione depletion, which may explain the effect of the extract in preventing mitochondrial dysfunction evaluated. Likewise, in the model of stress by restriction of movement, the extract of mate grass was more effective than the chlorogenic acid in preventing the behavioral alterations of the animals. The group that received extract as treatment had locomotor activity equal to or greater than the control group. The animals treated with extracts were also less anxious than those of the stressed group that did not receive treatment. In addition, the extract exhibited a protective effect on cell damage in cortex, hippocampal and striatum, as treated animals had a higher number of viable cells in these tissues. Regarding the effects of the extract in the induced model of diabetes, it was verified that the yerba mate has activity of protection to the oxidative stress involved in the pathogenesis of this pathology, in addition to significantly reduce the glycemic level of the animals and present protective effect to diabetic neuropathy. Based on the results found, it is possible to say that, in general, yerba mate acts in the protection of different aspects of oxidative stress due to the synergism of its components, considering that the isolated chlorogenic acid did not present a protective effect equal or greater than of the extract. Through its antioxidant effect, present benefits in reducing the damage caused by chronic hyperglycemia in diabetes mellitus, in the modulation of neuroprotective effects and mitochondrial function. CNPQ::CIENCIAS BIOLOGICAS Bioquímica Ilex paraguariensis Estresse oxidativo Antioxidantes Estresse crônico Dano celular Ilex paraguariensis Antioxidants Oxidative stress Cell damage Chronic stress
14	Tracking Cyanobacteria Cell Integrity through Chemical and Mechanical Stressors in the Water Treatment Process Elliott, Dane 30 September 2022 (has links) No description available. Civil Engineering Environmental Engineering Cyanobacteria harmful algal blooms drinking water treatment phycocyanin microcystis planktothrix cell damage lysis chemical oxidants permanganate chlorine mechanical shear
15	Valorization of apple by-products by the extraction and purification of polyphenols : impact of the ultrasound / Valorisation des sous-produits de pomme par extraction et purification de polyphénols : impact des ultrasons Wang, Lu 18 October 2019 (has links) Cette thèse porte sur l'intensification de l'extraction de polyphénols à partir de produits à base de pomme (chair, peau et marc) par ultrasons (US) et sur la purification d'extraits de peau de pomme par adsorption/désorption et technologie membranaire. L'extraction sélective des polyphénols issus des produits de la pomme a été analysée. Les données obtenues ont démontré la possibilité d’une régulation fine de l’extraction sélective de la matière soluble, de la catéchine et des composés polyphénoliques totaux en utilisant différentes températures, protocoles UAE, mélanges éthanol/aqueux. La sélectivité de l'extraction de la catéchine dépendait également du type de tissu (chair, peau ou marc) et de la variété de pomme (verte ou rouge). Le phénomène de cavitation généré par les ultrasons pourrait augmenter l'extraction de composants précieux des pelures de fruits en endommageant les membranes cellulaires des échantillons et en accélérant ainsi le transfert de chaleur et de masse. D’autre part, les solvants eau-gaz pourraient améliorer l'efficacité d'extraction des polyphénols des peaux de pomme en renforçant le phénomène de cavitation généré par les ultrasons. L'efficacité de la purification de polyphénols d'extraits de pelure de pomme par adsorption/désorption assisté par ultrasons (adsorbant polyaromatique Amberlite XAD-16) et par électrofiltration sur membrane a été mise en évidence. Les données obtenues ont démontré que la sonication facilitait significativement la cinétique d’adsorption, la capacité d’adsorption accrue et augmentation de l’énergie d’activation de l’adsorption des polyphénols. En outre, le taux de désorption a été positivement affecté par la sonication au cours de l'étape d'adsorption. Par ailleurs, les résultats ont montré que l’électrofiltration sur membrane permettait de purifier les polyphénols dans l’espace anodique (+) et d’obtenir un volume plus important de filtrats. / This thesis focuses on the intensification of polyphenols extraction from apple products (flesh, peel, and pomace) by ultrasound (US) and the purification of apple peel extracts by adsorption/desorption and membrane technology. The selective extraction of phenolic contents from apple products has been analyzed. The obtained data evidenced the possibility of fine regulation of selective extraction of soluble matter, catechin and total polyphenolic compounds using different temperatures, ultrasound-assisted extraction (UAE) protocols, ethanol/aqueous mixtures. The selectivity of catechin extraction was also depended on the type of the tissue (flesh, peel or pomace) and apple variety (green or red). The cavitation phenomenon generated by ultrasound could increase extraction of valuable components from fruit peels by damaging cell membranes of samples and accelerating heat and mass transfer by disrupted cell walls of samples. Meanwhile, the gas water solvents could enhance the extraction efficiency of polyphenols and antioxidant activity from apple peels by enhancing cavitation phenomenon generated by ultrasound. The efficiency of polyphenols purification from apple peel extracts with adsorption/desorption process by ultrasound treatment with the polyaromatic amberlite adsorbent XAD-16 and with membrane electro-filtration were studied. The obtained data demonstrated that the sonication significantly facilitated adsorption kinetics and increased activation energy of polyphenols adsorption. In addition, the desorption ratio was positively affected by the sonication during the adsorption step. On the other hand, the results demonstrated that the membrane electro-filtration allowed the purification of polyphenols in the anode (+) space and obtaining larger volume of filtrates. Peau de pomme Extraction sélective Endommagement cellulaire Désorption Filtration sur membrane Technologie membranaire Phénomène de cavitation Electrofiltration sur membrane Apple peel Polyphenols Ultrasound Selective extraction Cavitation phenomenon Cell damage Menbrane electro-filtration Sonochemistry Adsorption Desorption
16	Development of Sensitive In Vitro Assays to Assess the Ocular Toxicity Potential of Chemicals and Ophthalmic Products McCanna, David January 2009 (has links) 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. in vitro Alternative Methods alamarBlue rhodamine tight junctions bovine lens viability toxicity mitochondria mitochondria integrity benzalkonium chloride sodium dodecyl sulphate sodium lauryl sulfate scanning electron microscopy Draize Draize maximal average scores zonula occludens cosmetic directive PETA humane society animal league ICCVAM ECVAM JaCVAM BCOP bovine cornea ocular irritants ocular irritation ocular toxicity human corneal epithelial cells vitro confocal confocal microscopy metabolic activity optical quality reactive oxygen species contact lens contact lens care solutions barrier function microbial keratitis mulitipurpose solutions tight junction cell damage claudin ZO-1 occludin MDCK Madin Madin-Darby canine kidney cells cornea human cornea human corneal epithelium epithelial cell line human corneal epithelial cell line sodium fluorescein sodium fluorescein permeability fluorescein permeability ocular surface cell monolayer Araki-Sasaki cell physiology risk assessment safety assessment ScanTox scanning laser lens epithelium corneal cells in vitro model ophthalmic formulations multiple instillation back vertex animal testing rabbit testing alternatives to animal testing cultured bovine lens toxicity of chemicals irritation irritants laser scanner organ culture delayed toxicity toxins hydrogen peroxide cornea toxicity cornea toxicity models prediction of human toxicity no observable adverse effect level lowest observable adverse effect level NOAEL LOAEL toxicity thresholds safety factors cornea uncertainty factors preservatives disinfectants ophthalmic products preclinical preclinical testing epithelial barrier drug penetration clinical confocal microscopy animal rights rabbit cornea human cornea human clinical effects toxic animal rights activist sensitive measures toxic effect toxicity threshold agar overlay agar diffusion agar overlay method agar diffusion method cytochrome cytochrome c apoptosis necrotic apoptotic necrosis caspase rhodamine 123 resazuran resorufin cell death cell viability metabolic dye microsomal microsomal enzymes cytotoxicity cytotoxic cytotoxic effect MTT XTT WST-1 plasma membrane mitochondrial mitochondrial morphology ocular toxicity potential ocular toxicity human corneal epithelial cell line confocal analysis corneal epithelium cell fluorescence alamarBlue assay rhodamine dye animal welfare toxic injury degraded mitochondria epithelial monolayer disinfectants membrane integrity eye toxicity eye viability dye toxicity in humans human toxicity effects on the mitochondria mitochondrial toxicity in vitro battery in vitro test battery ophthalmic eye drop direct contact product safety cytotoxicity potential molecular molecular biology refine reduce replace sensitivity and relevance sensitivity relevance rabbit ocular irritation test product development cytotoxicity models cytotoxicity alternative methods replacements for animal testing three r's beagle tiered testing tiered testing strategy replacements animal testing mechanistic toxicity cornea mitochondria dose response threshold Vision Science and Biology
17	Development of Sensitive In Vitro Assays to Assess the Ocular Toxicity Potential of Chemicals and Ophthalmic Products McCanna, David January 2009 (has links) 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. in vitro Alternative Methods alamarBlue rhodamine tight junctions bovine lens viability toxicity mitochondria mitochondria integrity benzalkonium chloride sodium dodecyl sulphate sodium lauryl sulfate scanning electron microscopy Draize Draize maximal average scores zonula occludens cosmetic directive PETA humane society animal league ICCVAM ECVAM JaCVAM BCOP bovine cornea ocular irritants ocular irritation ocular toxicity human corneal epithelial cells vitro confocal confocal microscopy metabolic activity optical quality reactive oxygen species contact lens contact lens care solutions barrier function microbial keratitis mulitipurpose solutions tight junction cell damage claudin ZO-1 occludin MDCK Madin Madin-Darby canine kidney cells cornea human cornea human corneal epithelium epithelial cell line human corneal epithelial cell line sodium fluorescein sodium fluorescein permeability fluorescein permeability ocular surface cell monolayer Araki-Sasaki cell physiology risk assessment safety assessment ScanTox scanning laser lens epithelium corneal cells in vitro model ophthalmic formulations multiple instillation back vertex animal testing rabbit testing alternatives to animal testing cultured bovine lens toxicity of chemicals irritation irritants laser scanner organ culture delayed toxicity toxins hydrogen peroxide cornea toxicity cornea toxicity models prediction of human toxicity no observable adverse effect level lowest observable adverse effect level NOAEL LOAEL toxicity thresholds safety factors cornea uncertainty factors preservatives disinfectants ophthalmic products preclinical preclinical testing epithelial barrier drug penetration clinical confocal microscopy animal rights rabbit cornea human cornea human clinical effects toxic animal rights activist sensitive measures toxic effect toxicity threshold agar overlay agar diffusion agar overlay method agar diffusion method cytochrome cytochrome c apoptosis necrotic apoptotic necrosis caspase rhodamine 123 resazuran resorufin cell death cell viability metabolic dye microsomal microsomal enzymes cytotoxicity cytotoxic cytotoxic effect MTT XTT WST-1 plasma membrane mitochondrial mitochondrial morphology ocular toxicity potential ocular toxicity human corneal epithelial cell line confocal analysis corneal epithelium cell fluorescence alamarBlue assay rhodamine dye animal welfare toxic injury degraded mitochondria epithelial monolayer disinfectants membrane integrity eye toxicity eye viability dye toxicity in humans human toxicity effects on the mitochondria mitochondrial toxicity in vitro battery in vitro test battery ophthalmic eye drop direct contact product safety cytotoxicity potential molecular molecular biology refine reduce replace sensitivity and relevance sensitivity relevance rabbit ocular irritation test product development cytotoxicity models cytotoxicity alternative methods replacements for animal testing three r's beagle tiered testing tiered testing strategy replacements animal testing mechanistic toxicity cornea mitochondria dose response threshold Vision Science and Biology

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