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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Nitric oxide in brain contusion /

Gahm, Caroline, January 2005 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2005. / Härtill 5 uppsatser.
112

Factors influencing the risk of diabetic nephropathy : analyses of genes, smoking and diet /

Möllsten, Anna, January 2006 (has links)
Diss. (sammanfattning) Umeå : Umeå universitet, 2006. / Härtill 5 uppsatser.
113

Mechanisms of adenosine monophosphate-activated protein kinase-induced preconditioning in ischemia/reperfusion

Gaskin, F. Spencer, January 2007 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2007. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Vita. "August 2007" Includes bibliographical references.
114

Regulation of iNOS expression : in response to pressure in proximal tubule epithelial cells /

Broadbelt, Nalini V. January 2008 (has links)
Thesis (Ph. D.)--Cornell University, August, 2008. / Vita. Includes bibliographical references (leaves 116-140).
115

Modulation of the ACTH response to stress by IL-6, nitric oxide, diet and exercise

Jankord, Ryan, January 2006 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2006. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Vita. "December 2006" Includes bibliographical references.
116

Upregulation of COX-2 protein expression in porcine macula densa with L-NAME treatment

Kommareddy, Madhavi. January 2008 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2008. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Includes bibliographical references.
117

Interaction of metallic nanoparticles with biomedical enzyme target: neuronal nitric oxide synthase

Ngqwala, Nosiphiwe Patience January 2013 (has links)
Alzheimer's disease (AD) is the most common type of dementia characterized by intracellular appearance of neurofibrillary tangles, synaptic and neuronal loss; and extracellular accumulation of amyloid-β (Aβ) peptide in senile plaques. The initial causes leading to AD are unknown, and the available treatments are only effective at slowing the degeneration process. The accumulation of arginine in the brain of Alzheimer patients indicates a possible disruption of enzymes responsible for its metabolism. One such enzyme is neuronal nitric oxide synthase (nNOS) and controlling its activity by interacting with nanoparticles may lead to a delay in the onset of the disease. Neuronal nitric oxide synthase was purified using DEAE-Sephacel ion exchange resulting in 10 % yield, 0.43 fold recovery and specific activity 0.09 U/mg. The enzyme was found to be a dimer with a molecular mass of 150 kDa. Characterisation of the nNOS showed an optimum temperature and pH of 50°C and 7.5 respectively, and it was relatively stable at the optimum conditions (t½ = 100 min). The purity was analysed by SDS-PAGE followed by Western blot. Purified nNOS was challenged with 3-7 nm silver and 4-15 nm gold nanoparticles of between synthesized chemical using AgNO3 and either sodium borohydride or sodium citrate. Results showed that gold nanoparticles are more effective at low concentration (5 μM) than silver nanoparticles due to their size difference. Incubation of different concentration of nanoparticles (5, 15, 25, 50 μM) with the purified nNOS showed an initial decrease of 5% in enzyme activity which over time was restored to 80%. This suggests that different nanoparticles are produced in different sizes and interaction over a given time may result in enzyme association–dissociation mechanism. Inhibition studies showed a strong binding of both nanoparticles with Ki values of 1.4 μM and 0.2 μM for silver and gold, respectively. Both nanoparticles inhibited the activity of nNOS extensively as they bound strongly to the inhibition site on the enzyme and were more in contact with fluorophores nanoparticles. This was confirmed by fluorimetry with binding constants of 0.0084 μM and 0.01092 μM for silver and gold, respectively. Results of this study suggest that silver and gold nanoparticles competitively inhibit nNOS.
118

O papel do óxido nítrico na patogênese da leptospirose experimental em hamsters e camundongos

Santos, Cleiton Silva January 2014 (has links)
Submitted by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2015-03-06T17:21:16Z No. of bitstreams: 1 Cleiton Silva Santos O papel...2014.pdf: 3463624 bytes, checksum: e0ea46a25188ac23e355981d84456b5f (MD5) / Approved for entry into archive by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2015-03-06T17:44:04Z (GMT) No. of bitstreams: 1 Cleiton Silva Santos O papel...2014.pdf: 3463624 bytes, checksum: e0ea46a25188ac23e355981d84456b5f (MD5) / Made available in DSpace on 2015-03-06T17:44:04Z (GMT). No. of bitstreams: 1 Cleiton Silva Santos O papel...2014.pdf: 3463624 bytes, checksum: e0ea46a25188ac23e355981d84456b5f (MD5) Previous issue date: 2014 / Fundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, Brasil / A patogênese da leptospirose é pouco compreendida e os estudos com enfoque na resposta inflamatória sistêmica ou local são escassos, em especial no que se refere ao papel do óxido nítrico (NO) e da enzima óxido nítrico sintase induzível (iNOS). Dados de ensaios em culturas de células renais sugerem um papel importante da liberação de mediadores inflamatórios, tais como NO, na resposta às leptospiras e consequente nefrite intersticial. A transposição destes achados para o modelo in vivo foi pouco explorada. Por outro lado, estudos em humanos sugerem que a liberação sistêmica de NO correlaciona-se com a gravidade da doença renal e, portanto, pode ser um potencial alvo para terapia adjuvante à antibioticoterapia. O presente trabalho estudou a correlação da iNOS com distúrbios hidroeletrolíticos na patogênese da leptospirose. No modelo experimental de hamsters, avaliamos a associação da inibição dos efeitos do NO, através da terapia combinada de antibioticoterapia padrão e azul de metileno, com distúrbios eletrolíticos, alterações histopatológicas em hamsters e sobrevida. Nenhum benefício da terapia adjuvante com azul de metileno foi demonstrado. No modelo de camundongos transgênicos, investigamos o efeito da ausência do gene da iNOS na nefrite intersticial e na quantidade de bactérias observadas nos tecidos. A ausência do gene iNOS esteve associado a menor frequência de nefrite intersticial grave. Maiores estudos são necessários para investigar a função da inibição da produção de NO na patogenia da doença e da nefrite associada a leptospirose. / The pathogenesis of leptospirosis is poorly understood, and there are few studies fusing on the systemic or local inflammatory responses, especially referring to the role of nitric oxide (NO) and the enzyme inducible nitric oxide synthase (iNOS). Data from in vitro studies suggest an important role of inflammatory mediators, such as NO, in the response to leptospires in the development of interstitial nephritis. The transposition of these findings to an in vivo model was little explored. However, studies in humans suggest that systemic liberation of NO is correlated with severity of renal disease and therefore can be potential target to adjuvant therapy along with antibiotic therapy. The present work evaluated the correlation of iNOS with the pathogenesis of leptospirosis. In the experimental hamster model, we evaluated the effect of inhibiting downstream effects of NO on electrolytic disorders, histopathological changes and survival. No benefit of methylene blue treatment could be observed when compared to antibiotic (ampicillin) therapy only. In the mouse transgenic model, we investigated the effect of the absence of the Inos gene in interstitial nephritis and in the bacterial burden in target tissues. The absence of a functional iNOS gene was associated with lower frequency of severe interstitial nephritis.
119

Distribuição de celulas imunorreativas para sintase neuronal do oxido nitrico (nNOS) no hipocampo de pombos (Columba livia) apos aprendizagem de escolha alimentar / Distribution of neuronal nitric oxide synthase immunoreactive cells for neural in the hippocampus of pigeon after food-choice learning

Silva, Maria Isabel 28 February 2007 (has links)
Orientadores: Elenice Aparecida de Moraes Ferrari, Claudio Antonio Barbosa de Toledo / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-10T10:38:58Z (GMT). No. of bitstreams: 1 Silva_MariaIsabel_M.pdf: 1381550 bytes, checksum: 9cb336aef794086ff363f071f8040818 (MD5) Previous issue date: 2007 / Resumo: O hipocampo exerce papel fundamental no processamento de aprendizagem e memória espaciais. Comparações das características funcionais, anatômicas e neuroquímicas do hipocampo são favorecidas por evidência oriunda de estudo sobre aprendizagem especial em mamíferos e aves. O objetivo do presente estudo foi analisar a marcação imunohistoquímica de células nNOS- positivas no hipocampo de pombos (C. lívia) após diferentes duração do treino em aprendizagem especial. Foram analisados grupos de animais não treinados (MAN), treinados em 1 sessão (EXP1), treinados em 5 sessões (EXP5), exposto à arena em 1 sessão (CONT1) ou em 5 sessões (CONT5). As sessões foram realizadas numa arena onde havia quatro comedouros, um dos quais com alimento. Em cada sessão, com seis tentativas, registrou-se a latência (seg) e a assertividade da escolha de um comedouro. Após os testes comportamentais, usou-se imunoistoquímica para a análise da marcação de células nNOS-positiva no hipocampo dorsal e ventral. O grupo EXP5 teve diminuição da latência de escolha ('F IND. 4,28¿= 23,74; p < 0,001) e aumento das respostas corretas ('F IND. 4,35¿= 8,66; p < 0,001) em função do treino. A marcação das células nNOS-positivas no hipocampo foi significativamente maior no hipocampo dorsal dos animais EXP5 em comparação com o hipocampo ventral ('F IND. 4,22¿= 104,79; p<0,001) e com os demais grupos ('F IND. 4,22¿= 10,17; p < 0,001). O aumento da imunorratividade de células nNOS- positivas no hipocampo dorsal de pombos após a aprendizagem da localização do comedouro correto sugere o envolvimento desta região e de processos mediados pro transmissão glutamatérgica nesse processo de aprendizagem e memória em pombos / Abstract: The hippocampus has fundamental role in spatial learning and memory processes. Functional and neurochemical analysis of the hippocampus are favored by evidence on spatial learning in mammals and birds. The present study examined the immunohistochemical expression of nNOS-positive cells in the hippocampus of pigeons (C. livia) after training in food location task. Animals were trained in one (EXP1) or five (EXP5) sessions or had one (CONT1) or five sessions (CONT5) of exposure to the experimental arena. The six trials sessions were conducted daily in one arena with 4 food bowls, one of which had food. Latency and accuracy of choise recorded. After behavioral tests, nNOS immunoractivity in hippocampal cells was analyzed. EXP 5 showed reduction imunoreactivity in hippocampal cells was analysed. EXP5 showed reduction in latency of choise ('F IND. 4,28¿= 23,74; p < 0,001) and increassis in correct choise ('F IND. 4,35¿= 8,66; p < 0,001) as function of the training. The expression of nNOS- positive cells was significantily higher in the dorsal hippocampus of EXP5 group as compared with the ventral hippocampus ('F IND. 4,22¿= 104,79; p < 0,001) and the other groups ('F IND. 4,28¿= 10,17; p < 0,001). The increases of nNOS immunoreactive neurons after learning of the food location suggest that nNOS is involved in processes of spatial learning and memory that are mediated by the dorsal hippocampus of pigeons / Mestrado / Fisiologia / Mestre em Biologia Funcional e Molecular
120

Efeito da administração aguda e cronica de inibidores das oxido nitrico sintases na infiltração de eosinofilos para as vias aereas de camundongos alergicos / Effect of acute and chronic administration of nitric oxide synthase inhibitors on the eosinophil infiltration into the always of allergic mice

Souza Filho, Luis Gustavo de 1974- 08 June 2008 (has links)
Orientador: Edson Antunes / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-11T19:38:05Z (GMT). No. of bitstreams: 1 SouzaFilho_LuisGustavode1974-_M.pdf: 2079653 bytes, checksum: 497d01659ac0eed18bd9c81662ca0b59 (MD5) Previous issue date: 2008 / Resumo: Os inibidores das óxido nítrico sintases (NOS) são amplamente utilizados para avaliar a contribuição do NO na alergia pulmonar, mas os dados obtidos pela utilização de tais inibidores são controversos. Neste estudo, ensaios farmacológicos, bioquímicos e farmacocinéticos foram realizados para se avaliar os efeitos dos tratamentos agudo e crônico com o inibidor não seletivo da NOS, L-NAME, assim como do inibidor seletivo para NOS induzível (iNOS), aminoguanidina, sobre a inflamação das vias aéreas em camundongos BALB/c desafiados com ovalbumina (OVA). O tratamento crônico com L-NAME (50 e 150 mg/kg/dia, por três semanas) aumentou significativamente o número de eosinófilos no lavado broncoalveolar (LBA) de animais desafiados com ovalbumina (OVA; 0,19 ± 0,02 e 0,34 ± 0,03 x 106células/LBA, respectivamente; P<0,0001) em relação aos não tratados (0,13 ± 0,02 x 106 células/LBA). No parênquima pulmonar, o tratamento crônico com L-NAME (150 mg/kg/dia) também elevou significativamente o número de eosinófilos nos animais desafiados com OVA em relação aos animais não tratados (27,0 ± 5,1 e 18,2 ± 1,6 eosinófilos/brônquio, respectivamente; P<0,05). Contrariamente, os tratamentos agudo com L-NAME (50 mg/kg; gavagem 30 min antes do primeiro desafio com OVA) e crônico com aminoguanidina (20 mg/kg/dia, por três semanas) reduziram o número de eosinófilos no LBA (0,05 ± 0,01 e 0,04 ± 0,02 x 106 células/LBA, respectivamente; P<0,05) em relação ao controle. Os tratamentos agudo e crônico com L-NAME reduziram a atividade da NOS constitutiva (cNOS) no cérebro em relação aos animais não tratados (tratamento agudo: 5,8 ± 0,4 e 3,6 ± 0,2 pmol/min/mg de proteína; tratamento crônico: 5,7 ± 0,3 e 0,7 ± 0,2 pmol/min/mg de proteína, para controle e tratado, respectivamente; P<0,05). A atividade da NOS induzível (iNOS) pulmonar foi significativamente reduzida pelos tratamentos agudo com L-NAME e crônico com aminoguanidina (0,7 ± 0,05 e 0,04 ± 0,02 pmol/min/mg de proteína, respectivamente; P<0,05) em relação aos animais não tratados (1,2 ± 0,2 pmol/min/mg de proteína). Contudo, o tratamento crônico com L-NAME não afetou a atividade da iNOS pulmonar. Os níveis séricos de IgE mostraram-se elevados nos animais desafiados com OVA, mas não foram afetados por nenhum dos tratamentos. O tratamento crônico com aminoguanidina (mas não o tratamento crônico com L-NAME) reduziu os níveis elevados de eotaxina no LBA (3,4 ± 1,2 e 1,0 ± 0,5 pg/ml, para controle e tratado, respectivamente; P<0,05). As reduções dos níveis de NOx no LBA pelos tratamentos agudo com L-NAME e crônico com aminoguanidina (1,8 ± 0,4 e 0,6 ± 0,3 µM, respectivamente) foram maiores quando comparadas ao tratamento crônico com L-NAME (6,8 ± 0,6 µM) em relação aos animais não tratados (8,8 ± 0,8 µM). Os protocolos farmacocinéticos mostraram que o L-NAME não é biodisponível quando dado via oral. As concentrações séricas do metabólito do L-NAME, N?-nitro-L-arginina, diminuiram progressivamente de 30 min a 24 horas após a administração (72,0 a 32,1 ng/mL). No tratamento crônico com L-NAME, a concentração do N?-nitro-L-arginina (16,2 ng/mL) mostrou-se próxima do limite de detecção do método (10 ng/ml). Em conclusão, o tratamento crônico com L-NAME por três semanas produziu baixas concentrações séricas do N?-nitro-L-arginina, causando inibição preferencial da atividade da cNOS. Portanto, a potenciação do influxo de eosinófilos pelo tratamento crônico com L-NAME supostamente remove o NO protetor derivado da cNOS, com nenhuma interferência sobre o agravamento da inflamação devido ao NO oriundo da iNOS / Abstract: Nitric oxide synthase (NOS) inhibitors are largely used to evaluate the NO contribution to pulmonary allergy, but contrasting data have been obtained. In this study, pharmacological, biochemical and pharmacokinetic studies were performed to evaluate the effects of acute and chronic treatment of BALB/C mice with non-selective (L-NAME) and selective (aminoguanidine) NOS inhibitors in ovalbumin (OVA)-challenged mice. Long-term L-NAME treatment (50 and 150 mg/kg/day, three weeks) significantly increased the eosinophil number in bronchoalveolar lavage (BAL) fluid (0.19 ± 0.02 and 0.34 ± 0.03 x 106 cells / BAL, respectively; P<0.0001) in comparison with non-treated animals (0.13 ± 0.02 x 106 cells / BAL). In the bronchiolar parenchyma, chronic L-NAME treatment (150 mg/kg/day) also increased the eosinophil number (18.2 ± 1.6 and 27.0 ± 5.1 eosinophils/bronchio, for treated and untreated, respectively; P<0.05). On the other hand, acute L-NAME (50 mg/kg, given by gavage 30 min prior to the first OVA challenge) and aminoguanidine (20 mg/kg/day, three weeks) rather reduced the eosinophil number (0.05 ± 0.0 and 0.04 ± 0.02 x 106 cells / BAL, respectively; P<0.05). Chronic and acute L-NAME treatments markedly reduced the constitutive NOS (cNOS) activity in brain (0.7 ± 0.2 and 3.6 ± 0.2 pmol/min/mg of protein, respectively; P<0.05) in comparison with untreated animals (5.7 ± 0.3 and 5.8 ± 0.4 pmol/min/mg of protein, respectively). The inducible pulmonary NOS (iNOS) activity was markedly reduced by acute L-NAME and aminoguanidine (0.7 ± 0.05 and 0.04 ± 0.02 pmol/min/mg of protein, respectively; P<0.05) compared with untreated animals (1.2 ± 0.2 pmol/min/mg of protein). In contrast, chronic L-NAME failed to affect the iNOS activity. The increased serum IgE levels seen in OVA-challenged animals were not affected by any treatment. Aminoguanidine (but not chronic L-NAME) restored the increased eotaxin levels in BAL (3.4 ± 1.2 and 1.0 ± 0.5 pg/ml; P<0.05). The NOx- levels in BAL fluid were reduced by both acute and chronic L-NAME, as well as by aminoguanidine (1.8 ± 0.4, 6.8 ± 0.6 and 0.6 ± 0.3 µM, respectively; P<0.05) compared with untreated animals (8.8 ± 0.8 µM); however, the reductions of NOx- levels by acute L-NAME and aminoguanidine were significantly higher than the chronic L-NAME treatment. The pharmacokinetic protocols showed that L-NAME per se is not bioavailable when given per os. The serum concentrations of its metabolite N?-nitro-L-arginine decreased from 30 min to 24 h (72.0 to 32.1 ng/mL) after acute L-NAME intake. In chronic treatment, N?-nitro-L-arginine concentration (16.2 ng/mL) was close to the detection limit (10 ng/mL). In conclusion, 3-week treatment with L-NAME yields low serum N?-nitro-L-arginine concentrations, causing a preferential inhibition of cNOS activity. Therefore, potentiation of eosinophil influx by chronic L-NAME reflects a removal of protective cNOS-derived NO, with no interference on the ongoing inflammation due to iNOS-derived NO / Mestrado / Mestre em Farmacologia

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