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Estudo experimental avaliando os efeitos de nanopartículas naturais e transialidase - componentes do PTCTS - no combate à aterosclerose em coelhos / Experimental study evaluating the effects of natural nanoparticles and transialidase - PTCTS components - combating atherosclerosis in rabbitsGaravelo, Shérrira Menezes 21 November 2016 (has links)
A aterosclerose é um processo sistêmico crônico, caracterizado pela presença de lesões, espessamento da parede arterial com acúmulo de lipídeos, e resposta inflamatória e fibroproliferativa. Muitos processos associados à oxidação da LDL, ao aumento de expressão de fatores prótrombóticos, moléculas de adesão próinflamatórias, citocinas e fatores quimiotáticos estão envolvidos na fisiopatologia da doença aterosclerótica. Trabalhos anteriores mostraram a presença de Mycoplasma pneumoniae (Mic) em placas lipídicas vulneráveis, associada à liberação de micropartículas (MPs) capazes de interagir com o ambiente e influenciar o processo aterogênico. Assim, a H&S Ciência e Biotecnologia, desenvolveu o complexo PTCTS que tem em sua composição nanopartículas naturais provenientes de plantas medicinais (PTC) associadas à enzima transialidase (TS) para combater as MPs e o Mic, além de ter efeito antilipemiante e antiaterosclerótico. O presente estudo teve como objetivo verificar os efeitos dos diferentes componentes do PTCTS administrados por via oral em relação à eficácia, toxicidade e mecanismo de ação na terapia antiaterosclerótica em coelhos hipercolesterolêmicos. Foram estudados coelhos da raça Nova Zelândia separados randomicamente em 6 grupos de tratamento: Controle Negativo (CNeg n=6), Controle Positivo (CPos n=6), Partículas orgânicas (PTC n=6), Transialidase (TS n=5), Partículas orgânicas associadas à transialidase (PTCTS n=6), e PTCTS com adição de PDTC (n=6). Os animais foram alimentados com dieta enriquecida com colesterol por doze semanas, exceto o CNeg, e receberam seus respectivos tratamentos durante as últimas seis semanas, concomitantemente à dieta hipercolesterolêmica. Tiveram sangue coletado durante as fases basal, pré e pós tratamento, para avaliação bioquímica do perfil lipídico, transaminases hepáticas e quantificação de MPs associadas a antígenos de Mic e LDLox no soro. Ao fim do experimento, foram sacrificados, e tiveram a aorta colhida em conjunto com o monobloco de órgãos para análises morfométrica, histológica, e imunohistoquímica, de forma a verificarmos os efeitos do PTCTS e seus compostos. O composto PTCTS via oral se mostrou eficaz quanto a eliminação de MPs associadas tanto a antígenos de Mic como de LDLox, e apesar de não ter tido os efeitos antiateroscleróticos e antilipemiantes esperados, reduziu não significativamente a área de placa na porção abdominal da aorta, induziu a aorta ao remodelamento positivo, permitindo um fluxo livre mesmo com uma grande área de placa, e evitando assim a obstrução do vaso. Seus componentes, quando administrados isoladamente tiveram efeitos parciais, as PTC sobre o remodelamento do vaso e redução de placa na aorta abdominal, e a TS sobre a redução do colesterol total, comprovando que a associação de ambos possui atividade mais completa e balanceada. A adição do PDTC ao complexo levou ao efeito oposto, ao inibir a atividade de eliminação de MPs apresentada pelo PTCTS, bem como ao induzir remodelamento negativo dos vasos. Nenhum dos componentes apresentou toxicidade nos órgãos estudados. Os dados encontrados neste trabalho experimental reforçam a teoria infecciosa na patogenia da aterosclerose, bem como a de que MPs originadas de tais microorganismos possam estar induzindo a produção de radicais livres e influenciando a oxidação de lípides, de forma que a remoção de tais patógenos do sangue circulante pode ser um novo caminho terapêutico no tratamento da aterosclerose / Atherosclerosis is a chronic systemic process, characterized by lesions, thickening of the arterial wall with accumulation of lipids, inflammatory and fibroproliferative response. Many processes associated with the oxidation of LDL, increase expression of prothrombotic factors, adhesion molecules, proinflammatory cytokines and chemotactic factors are involved in the pathophysiology of atherosclerosis. Previous works have shown the presence of Mycoplasma pneumoniae (Mic) in vulnerable lipid plaques, associated with the release of microparticles (MPs) able to interact with the environment and influence the atherogenic process. Thus, H&S Science and Biotechnology developed the PTCTS complex, which has in its composition natural nanoparticles from medicinal plants (PTC) associated with transialidase enzyme (TS), to combat MPs and Mic, that together have antilipemiante and antiaterosclerotic effects. This study aimed to determine the effects of different components of PTCTS administered orally regarding the efficacy, toxicity and mechanism of action in antiatherosclerotic therapy in hypercholesterolemic rabbits. It was studied White New Zealand rabbits separated randomly into six treatment groups: Negative Control (CNeg n=6), Positive Control (CPos n=6), organic particles (PTC n=6), transialidase (TS n=5) organic particles attached to transialidase (PTCTS n=6) and PTCTS with addition of PDTC (n=6). The animals were fed with a diet enriched with cholesterol for twelve weeks, except the CNeg, and received their treatments during the last six weeks, concurrently with hypercholesterolemic diet. Blood samples were taken during the baseline, pre and post treatment phases for biochemical evaluation of the lipid profile, liver transaminases and quantification of MPs associated with Mic antigens and oxLDL in the serum. At the end of the experiment they were sacrificed and the aorta was harvested together with the monoblock of organs for morphometric analysis, histology and immunohistochemistry, so we could check the effects of PTCTS and their compounds. The compound PTCTS orally is effective at removing MPs associated with both Mic and oxLDL antigens, and despite not having had the expected antiatherosclerotic and antilipemiantes effects, reduced not significantly plaque area in the abdominal portion of aorta, and induced its ascendant portion to positive remodeling, allowing a free flow even with large plate area, avoiding obstruction of the vessel. Its components when administered alone had partial effects, PTC on the remodeling of the vessel and plaque reduction in the abdominal aorta, and TS on the reduction of total cholesterol, proving that the combination of both has more complete and balanced activity. The addition of PDTC to the complex led to the opposite effect to inhibit MPs scavenging activity displayed by PTCTS as well as to induce negative remodeling of vessels. None of the components presented toxicity in the organs studied. The data found in experimental work reinforce the infectious theory on the pathogenesis of atherosclerosis as well as that originating MPs such microorganisms may be inducing the production of free radicals and oxidation of lipids, so that the removal of such pathogens from circulating blood may be a new therapeutic approach in the treatment of atherosclerosis
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Estudo experimental avaliando os efeitos de nanopartículas naturais e transialidase - componentes do PTCTS - no combate à aterosclerose em coelhos / Experimental study evaluating the effects of natural nanoparticles and transialidase - PTCTS components - combating atherosclerosis in rabbitsShérrira Menezes Garavelo 21 November 2016 (has links)
A aterosclerose é um processo sistêmico crônico, caracterizado pela presença de lesões, espessamento da parede arterial com acúmulo de lipídeos, e resposta inflamatória e fibroproliferativa. Muitos processos associados à oxidação da LDL, ao aumento de expressão de fatores prótrombóticos, moléculas de adesão próinflamatórias, citocinas e fatores quimiotáticos estão envolvidos na fisiopatologia da doença aterosclerótica. Trabalhos anteriores mostraram a presença de Mycoplasma pneumoniae (Mic) em placas lipídicas vulneráveis, associada à liberação de micropartículas (MPs) capazes de interagir com o ambiente e influenciar o processo aterogênico. Assim, a H&S Ciência e Biotecnologia, desenvolveu o complexo PTCTS que tem em sua composição nanopartículas naturais provenientes de plantas medicinais (PTC) associadas à enzima transialidase (TS) para combater as MPs e o Mic, além de ter efeito antilipemiante e antiaterosclerótico. O presente estudo teve como objetivo verificar os efeitos dos diferentes componentes do PTCTS administrados por via oral em relação à eficácia, toxicidade e mecanismo de ação na terapia antiaterosclerótica em coelhos hipercolesterolêmicos. Foram estudados coelhos da raça Nova Zelândia separados randomicamente em 6 grupos de tratamento: Controle Negativo (CNeg n=6), Controle Positivo (CPos n=6), Partículas orgânicas (PTC n=6), Transialidase (TS n=5), Partículas orgânicas associadas à transialidase (PTCTS n=6), e PTCTS com adição de PDTC (n=6). Os animais foram alimentados com dieta enriquecida com colesterol por doze semanas, exceto o CNeg, e receberam seus respectivos tratamentos durante as últimas seis semanas, concomitantemente à dieta hipercolesterolêmica. Tiveram sangue coletado durante as fases basal, pré e pós tratamento, para avaliação bioquímica do perfil lipídico, transaminases hepáticas e quantificação de MPs associadas a antígenos de Mic e LDLox no soro. Ao fim do experimento, foram sacrificados, e tiveram a aorta colhida em conjunto com o monobloco de órgãos para análises morfométrica, histológica, e imunohistoquímica, de forma a verificarmos os efeitos do PTCTS e seus compostos. O composto PTCTS via oral se mostrou eficaz quanto a eliminação de MPs associadas tanto a antígenos de Mic como de LDLox, e apesar de não ter tido os efeitos antiateroscleróticos e antilipemiantes esperados, reduziu não significativamente a área de placa na porção abdominal da aorta, induziu a aorta ao remodelamento positivo, permitindo um fluxo livre mesmo com uma grande área de placa, e evitando assim a obstrução do vaso. Seus componentes, quando administrados isoladamente tiveram efeitos parciais, as PTC sobre o remodelamento do vaso e redução de placa na aorta abdominal, e a TS sobre a redução do colesterol total, comprovando que a associação de ambos possui atividade mais completa e balanceada. A adição do PDTC ao complexo levou ao efeito oposto, ao inibir a atividade de eliminação de MPs apresentada pelo PTCTS, bem como ao induzir remodelamento negativo dos vasos. Nenhum dos componentes apresentou toxicidade nos órgãos estudados. Os dados encontrados neste trabalho experimental reforçam a teoria infecciosa na patogenia da aterosclerose, bem como a de que MPs originadas de tais microorganismos possam estar induzindo a produção de radicais livres e influenciando a oxidação de lípides, de forma que a remoção de tais patógenos do sangue circulante pode ser um novo caminho terapêutico no tratamento da aterosclerose / Atherosclerosis is a chronic systemic process, characterized by lesions, thickening of the arterial wall with accumulation of lipids, inflammatory and fibroproliferative response. Many processes associated with the oxidation of LDL, increase expression of prothrombotic factors, adhesion molecules, proinflammatory cytokines and chemotactic factors are involved in the pathophysiology of atherosclerosis. Previous works have shown the presence of Mycoplasma pneumoniae (Mic) in vulnerable lipid plaques, associated with the release of microparticles (MPs) able to interact with the environment and influence the atherogenic process. Thus, H&S Science and Biotechnology developed the PTCTS complex, which has in its composition natural nanoparticles from medicinal plants (PTC) associated with transialidase enzyme (TS), to combat MPs and Mic, that together have antilipemiante and antiaterosclerotic effects. This study aimed to determine the effects of different components of PTCTS administered orally regarding the efficacy, toxicity and mechanism of action in antiatherosclerotic therapy in hypercholesterolemic rabbits. It was studied White New Zealand rabbits separated randomly into six treatment groups: Negative Control (CNeg n=6), Positive Control (CPos n=6), organic particles (PTC n=6), transialidase (TS n=5) organic particles attached to transialidase (PTCTS n=6) and PTCTS with addition of PDTC (n=6). The animals were fed with a diet enriched with cholesterol for twelve weeks, except the CNeg, and received their treatments during the last six weeks, concurrently with hypercholesterolemic diet. Blood samples were taken during the baseline, pre and post treatment phases for biochemical evaluation of the lipid profile, liver transaminases and quantification of MPs associated with Mic antigens and oxLDL in the serum. At the end of the experiment they were sacrificed and the aorta was harvested together with the monoblock of organs for morphometric analysis, histology and immunohistochemistry, so we could check the effects of PTCTS and their compounds. The compound PTCTS orally is effective at removing MPs associated with both Mic and oxLDL antigens, and despite not having had the expected antiatherosclerotic and antilipemiantes effects, reduced not significantly plaque area in the abdominal portion of aorta, and induced its ascendant portion to positive remodeling, allowing a free flow even with large plate area, avoiding obstruction of the vessel. Its components when administered alone had partial effects, PTC on the remodeling of the vessel and plaque reduction in the abdominal aorta, and TS on the reduction of total cholesterol, proving that the combination of both has more complete and balanced activity. The addition of PDTC to the complex led to the opposite effect to inhibit MPs scavenging activity displayed by PTCTS as well as to induce negative remodeling of vessels. None of the components presented toxicity in the organs studied. The data found in experimental work reinforce the infectious theory on the pathogenesis of atherosclerosis as well as that originating MPs such microorganisms may be inducing the production of free radicals and oxidation of lipids, so that the removal of such pathogens from circulating blood may be a new therapeutic approach in the treatment of atherosclerosis
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Modélisation des particules organiques dans l'atmosphère / Modelling organic particles in the atmosphereCouvidat, Florian 15 November 2012 (has links)
La formation des aérosols organiques dans l'atmosphère est étudiée via le développement d'un nouveau modèle de formation d'aérosols organiques secondaires nommé H²O (Hydrohilic/Hydrophobic Organics). Dans un premier temps, une paramétrisation de la formation d'aérosols via l'oxydation de l'isoprène est développée. Cette paramétrisation prend notamment en compte l'influence des concentrations d'oxydes d'azote sur la formation d'aérosols et leurs propriétés hydrophiles. Ensuite, H²O incluant cette paramétrisation et d'autres développements est évalué par comparaison aux mesures de carbone organique sur l'Europe. Prendre en compte les émissions de composés semi-volatils primaires gazeux (qui peuvent former des aérosols organiques secondaires après oxydation ou se condenser lors de baisses de température) améliore les performances du modèle de manière significative. En revanche, si les émissions de ces composés ne sont pas prises en compte, il en résulte une très forte sous-estimation des concentrations d'aérosols organiques en hiver. La formation d'aérosols organiques secondaires sur l'Île-de-France durant la campagne d'été de Megapoli (juillet 2009) a aussi été simulée pour évaluer les performances du modèle en zone urbaine. H²O donne de bons résultats sur l'Île-de-France bien que le modèle prévoit un pic d'aérosols organiques, provenant des émissions du trafic durant les heures de pointe, qui n'apparaît pas dans les mesures. La présence de ce pic dans les résultats du modèle peut être due à la sous-estimation de la volatilité des composés semi-volatils primaires. Il est aussi possible que les composés organiques primaires et les composés organiques secondaires ne se mélangent pas et que les composés semi-volatils primaires ne peuvent pas se condenser sur un aérosol organique majoritairement secondaire et très oxydé. Enfin, l'impact de la chimie aqueuse est étudié. Le mécanisme utilisé inclue notamment, la formation d'aérosols organiques secondaires dans la phase aqueuse des nuages par oxydation du glyoxal, du méthylglyoxal, de la méthacroleine et de la méthyl-vinyl-cétone, la formation de méthyltétrols dans la phase aqueuse des particules ou des gouttes d'eau des nuages et le vieillissement des aérosols organiques dans un nuage. L'impact des dépôts humides sur la formation d'aérosols est aussi étudié pour mieux caractériser l'impact des nuages sur les concentrations d'aérosols organiques / Rganic aerosol formation in the atmosphere is investigated via the developpement of a new model named H²O (Hydrohilic/Hydrophobic Organics). First, a parameterization is developped to take into account secondary organic aerosol formation from isoprene oxidation. It takes into account the effect of nitrogen oxides on organic aerosol formation and the hydrophilic properties of the aerosols. This parameterization is then implemented in H²O along with some other developments and the results of the model are compaired to organic carbon measurements over Europe. Model performance is greatly improved by taking into account emissions of primary semi-volatile compounds, which can form secondary organic aerosols after oxidation or can condense when temperature decreases. If those emissions are not taken into account, a significant underestimation of organic aerosol concentrations occurs in winter. The formation of organic aerosols over an urban area was also studied by simulating organic aerosols concentration over the Paris area during the summer campaign of Megapoli (July 2009). H²O gives satisfactory results over the Paris area, although a peak of organic aerosol concentrations from traffic, which does not appear in the measurements, appears in the model simulation during rush hours. It could be due to an underestimation of the volatility of organic aerosols. It is also possible that primary and secondary organic compounds do not mix well together and that primary semi volatile compounds do not condense on an organic aerosol that is mostly secondary and highly oxidized. Finally, the impact of aqueous-phase chemistry was studied. The mechanism for the formation of secondary organic aerosol includes in-cloud oxydation of glyoxal, methylglyoxal, methacrolein and methylvinylketone, formation of methyltetrols in the aqueous phase of particles and cloud droplets, and the in-cloud aging of organic aerosols. The impact of wet deposition is also studied to better estimate the impact of clouds on organic aerosol concentrations
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Design, Synthesis and Applications of Novel Two-Component Gels and Soft-NanocompositesBhattacharjee, Subham January 2014 (has links) (PDF)
No description available.
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