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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.
161

Estudo fitoquímico e biológico da espécie vegetal Manilkara Subsericea (Mart.) Dubard

Fernandes, Caio Pinho 30 March 2017 (has links)
Submitted by Biblioteca da Faculdade de Farmácia (bff@ndc.uff.br) on 2017-03-30T16:59:58Z No. of bitstreams: 1 Fernandes, Caio Pinho [Dissertação, 2011].pdf: 2382170 bytes, checksum: 7a855b1da9b229c8c3803eccbfdf9be5 (MD5) / Made available in DSpace on 2017-03-30T16:59:58Z (GMT). No. of bitstreams: 1 Fernandes, Caio Pinho [Dissertação, 2011].pdf: 2382170 bytes, checksum: 7a855b1da9b229c8c3803eccbfdf9be5 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Manilkara subsericea (Mart.) Dubard (Sapotaceae) é popularmente cohecida no Brasil como “guracica”. Neste trabalho, é descrito o fracionamento bioguiado pelo ensaio para inibidores da acetilcolinesterase de uma mistura contendo acetato de beta-amirina e acetato de alfa-amirina e a obtenção de uma mistura de ácido ursólico e ácido oleanólico. Esta é a primeira vez que a atividade anticolinesterásica de uma mistura contendo acetato de beta amirina (76,3%) e acetato de alfa amirina (23,7%) é descrita. Também foi verificada a eficiência de extratos de polaridade distintas e da misturas dos acetatos de beta e alfa amirina no desenvolvimento de duas espécies de insetos (Oncopeltus fasciatus e Dysdercus peruvianus). O extrato etanólico de folhas e os extratos hexânico, diclorometânico, acetato de etila e butanólico provenientes da partição realizada com o extrato etanólico bruto de frutos foram capazes de induzir mortalidade, atraso no desenvolvimento e inibição da muda. Além disso, os extratos hexânico, diclorometânico e butanólico, causaram mal formação em insetos adultos. Estes resultados indicam que extratos de M. subsericea atuam como inibidores do crescimento de fitófagos e que o acetato de beta amirina e acetato de alfa amirina podem ser utilizados como potenciais marcadores químicos em possíveis formulações de produtos para controle de pragas agrícolas. Extratos e fração obtida de M. subsericea foram testados frente a Staphylococcus aureus ATCC 25923 e Escherichia coli ATCC 25922. O extrato etanólico de folhas, extrato etanólico de caules, extrato hexânico de caules, extrato diclorometânico de caules, extrato acetato de etila de caules, extrato butanólico de caules, extrato hexânico de frutos, extrato diclorometânico de frutos e a mistura dos acetatos de beta e alfa amirina mostraram atividade frente a S. aureus. Somente o extrato etanólico de caules apresentou atividade frente a E. coli. Este é o primeiro estudo sobre atividade biológicas e fitoquímico de M. subsericea e esperamos com estes resultados, contruir para a valorização desta espécie / Manilkara subsericea (Mart.) Dubard (Sapotaceae) is popularly known in Brazil as “guracica”. In the present study, it is reported the bioguided fractionation by the bioassay for anticholinesterase inhibitors of a mixture containing beta-amyrin acetate and alpha-amyrin acetate and the achievement of a mixture containing oleanolic acid and ursolic acid. This was the first time that the anticholinesterasic activity of a mixture containg the triterpenes beta-amyrin acetate (76.3%) and alpha-amyrin acetate (23.7%) was described. We also evaluated the efficacy of extracts with distinct polarity and of the mixture of beta- and alpha-amyrin acetate from Manilkara subsericea on the development of two species of agricultural pest insects (Oncopeltus fasciatus and Dysdercus peruvianus). The etanolic extract from leaves, the hexanic extract, dichloromethanic extract, ethyl acetate extract and buthanolic extract from fruits were able to induce mortality, delay development and molt inhibition. These results indicate that M. subsericea extracts acts as a potent growth inhibitor of phytophagous hemipteran nymphs and indicates that beta- and alpha-amyrin acetate can be used as chemical markers for possible formulations of products to be used in control programs against crop pests. On the present study we tested M. subsericea extracts against Staphylococcus aureus ATCC 25923 e Escherichia coli ATCC 25922. The ethanolic extract from leaves, ethanolic extract from stems, hexanic extract from stems, dichloromethanic extract from stems, ethyl acetate extract from stems, buthanolic extract from stems, hexanic extract from fruits, dichloromethanic extract from fruits and a mixture of beta- and alpha amyrin acetates showed activity against S. aureus, with exception of the the ethyl acetate extract and buthanol extract from fruits. Only the ethanolic extract from stems showed activity against E. coli. This is the first contribution about phytochemistry and biological activities of M. subsericea and we hope that these results contribute for preservation of this species
162

Avaliação de novos compostos sobre a atividade de colinesterases em modelos in silico e in vitro / Evaluation of new compounds on cholinesterases activity in models in silico and in vitro

Lugokenski, Thiago Henrique 04 June 2012 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The enzyme acetylcholinesterase (EC 3.1.1.7, AChE) is responsible to terminate acetylcholine activity in the terminal nervous junctions with its effector organs or post-synaptic sites. The activity of this enzyme could be inhibited by organophosphorus (OP) compounds, and this inactivation leads to an accumulation of acetylcholine in the cholinergic receptors, leading to a cholinergic crisis that may result in death. In this way, the OP compound methamidophos has been related to its broad use in various agriculture cultures in Brazil, with high intoxication rate. Actually, the only compounds able to revert the AChE inhibition by OP, are the oxime, such compounds may reactive the enzyme activity due its high nuclephilic power, attacking the phosphoryl group of the inhibited enzyme and displacing it. However, such compounds show toxic effects, and its use is limited by the high specificity, with each oxime acting only in the reactivation of AChE induced by specific OP coumponds. These limitations raise the need of development of new compounds with AChE reactivator potency, with minor side effects. In this way, have been utilized a series of computational tools (in silico models), with the aim of understand the interaction occurring at a molecular level and, so, rationalize the new compounds development. Thus, the aim of this thesis is to evaluate the activity of three new compounds in reactivate the AChE inhibited by methamidophos, in comparison with two others oximes used in clinical (obidoxime and pralidoxime), both in in silico and in vitro models. Our work demonstrate that the newly synthesized compounds are able to reactivate human erythrocyte AChE, however less efficiently than pralidoxime and obidoxime, and reactivate human plasma butyrylcholinesterase (BChE), where the classical oximes failed. We also show that pralidoxime, which obtained the best reactivation constant among all tested compounds, attack the phosphorus-oxygen moiety (formed between the methamidophos and the AChE catalytic triad residue Ser203) via a region known as oxyanion-hole , composed by the residues Gly120, Gly121 and Ala204. Such found may help in the development of new compounds with better reactivatory activity on AChE inhibited by OP compounds. Furthermore, we show for the first time the individual contribution of each amino acid of AChE, in a radii of 14 Å from the ligand, to the oxime bonding to its active site, using quantum chemistry methods. Here, we demonstrate the important of a quaternary nitrogen to the stabilization of the oximes into the active site; as well as, we obtained evidences that the active form of oximes should be the unprotonated one, instead the protonated, which has been target of debate in the scientific society. Particularly important, we show the critical contribution of amino acids that lies distant from the ligand to the adopted conformation and stabilization of the compounds into the active site of AChE, which has been neglected until far. Finally, our study also evaluates the toxic effects of the compound isatin-3-N4-benzilthiosemicarbazone (IBTC) in mice, which presented low toxicity, with median lethal dose superior at 500 mg/kg. Concluding, this study contributes significantly to the development of new drugs able to restore the AChE activity with minor toxic effects. / A enzima acetilcolinesterase (EC 3.1.1.7, AChE) é responsável por terminar a ação da acetilcolina nas junções das terminações nervosas com seus órgãos efetores ou sítios pós-sinaptícos. A atividade desta enzima pode ser inibida por compostos organofosforados (OP), e sua inativação resulta em um acúmulo de acetilcolina nos receptores colinérgicos, levando a crise colinérgica que pode levar a morte. No Brasil, se destaca o uso do composto OP metamidofós, que é largamente utilizado no controle de pragas em culturas agrícolas e tem sido relacionado com altas taxas de intoxicação. Atualmente, os únicos compostos capazes de reverter a inibição da AChE por OP são as oximas, tais compostos podem reativar a enzima devido a seu alto poder nucleofílico, podendo atacar e retirar o grupamento fosforil da enzima inibida. Porém, tais compostos apresentam efeitos tóxicos, e tem seu uso limitado pela alta especificidade, com cada oxima atuando na AChE inibida por apenas alguns compostos OP. Tais limitações criam a necessidade do desenvolvimento de novos fármacos com potencial reativador da AChE com menores efeitos colaterais. Neste sentido, se tem utilizado uma série de ferramentas computacionais (modelos in silico), com o objetivo de entender as interações que ocorrem em nível molecular e, desta forma, racionalizar o desenvolvimento de novos compostos. Sendo assim, o objetivo desta tese consiste em avaliar a atividade de três novos compostos, em comparação com duas oximas já utilizadas na clínica (obidoxima e pralidoxima), sobre a atividade da AChE inibida por metamidofós, tanto em modelos in silico como in vitro. Como resultados, observamos que os três novos compostos foram capazes de reativar a AChE de eritrócitos humanos inibida por metamidofós, contudo com menor eficiência que as oximas já utilizadas na clínica. Porém, todos os novos compostos foram capazes de reativar a enzima butirilcolinesterase (BChE), uma enzima acessória à AChE no sistema colinérgico, inibida por metamidofós, enquanto nenhumas das oximas clássicas tiveram qualquer atividade reativadora nesta enzima. Nosso trabalho também demonstrou que a pralidoxima, que obteve a melhor constante de reativação entre todos os compostos testados, ataca a ligação fosforo-oxigênio (formada entre o metamidofós e o resíduo Ser203, da tríade catalítica da AChE) via uma região conhecida como oxyanion-hole , que compreende os resíduos Gly120, Gly121 e Ala204. Tal achado pode ajudar no desenvolvimento de novos compostos com melhor atividade reativatória na AChE inibida por OPs. Além disso, mostramos aqui pela primeira vez, a contribuição de cada resíduo de aminoácido da AChE, num raio de 14 Å do ligante, para a ligação das oximas no seu sítio ativo, usando métodos de química quântica. Tais achados mostraram a importância da presença de um nitrogênio quaternário para a estabilização das oximas no sítio ativo; assim como colheu evidências que a forma ativa das oximas seria a sua forma desprotonada, ao invés da forma protonada, o que tem sido alvo de algum debate no meio cientifico. Particularmente importante, foi demonstrado a contribuição fundamental de aminoácidos que se encontram distantes do ligante, para a estabilização e conformação adotada pelos compostos, e que até o momento tem sido negligenciados em estudos in silico. Por fim, nosso estudo também avaliou os efeitos tóxicos do composto isatina-3-N4-benziltiosemicarbazona (IBTC) em camundongos, o qual apresentando baixa toxicidade, com valores de dose letal mediana (LD50) superiores a 500 mg/kg. Desta forma, este estudo contribui para a desenvolvimento de novos fármacos capazes de reativar a AChE e que apresentem menos efeitos tóxicos.
163

Atividades das colinesterases em ratos infectados experimentalmente por Sporothrix schenckii / Activities cholinesterase in rats experimentally infected by Sporothrix schenckii

Castro, Verônica Souza Paiva 19 August 2015 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Sporotrichosis is an implantation mycose, caused by species complex Sporothrix spp., considered the subcutaneous mycosis with higher occurrence and importance in the Americas, this thermally dimorphic fungus induces a chronic inflammatory granulomatous response in their hosts. The cholinesterase, acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) are the "key" enzimes signal in inflammatory and immune processes, for regulating the levels of ACh, the main neurotransmitter "cholinergic antiinflammatory pathway". The cholinesterase activity has been demonstrated in various inflammatory conditions; however, there is no evidence of his participation in sporotrichosis. The objective of this study was to report a case of feline sporotrichosis by natural infection; evaluate the activities of AChE in the lymphocytes and whole blood; evaluate the activity of BChE; cytokines (IL1, IL6, TNF, and IL-10 INFγ) and immunoglobulins (IgA, IgG, IgM, IgE) in serum of rats experimentally infected with S. schenckii. Sixty-three rats were divided into three groups, control group (CG), group by subcutaneous infection (GSC) and group by intraperitoneal infection (GIP). Blood collection for activities evaluation of cholinesterase, cytokines and immunoglobulins were held on 15, 30 and 40 post-infection (PI). The GIP, had an increase in the activity of AChE in the blood in all experimental times, the increase in lymphocytes occurred only on 30 and 40 days PI. The increase of the enzyme suggests a decrease in the levels of ACh with consequently increased IL-1, IL-6, TNF-α, INF-γ, as observed in this study. In the acute phase of infection wants an intense inflammatory response in an attempt to remove the agent. However, with the chronicity of infection if the stimulus is maintained can lead to remarkable tissue injury. Regarding the chronic process observed in GIP, 30 and 40 days PI, that IL-10 was shown to be increased, but not enough to contain inflammation, as pro cytokines, continued high levels. Conversely, what happened in the GIP, the SC group had reduced levels of IL-10 at all times PI, this decrease can lead to tissue damage by not blocking the inflammatory response. The activity of AChE in the GSC only statistically increased in lymphocytes, at 40 days PI. There was no significant activity when assessing the BChE, in both groups, except in the GSC 40 days PI. The BChE is not efficient in Ach s hydrolysis in low concentrations, but it can replace the AChE when itself is inhibited. High levels of immunoglobulins in all groups and at all times, shows the induction of humoral immune response in sporotrichosis. Thus, the increase in the AChE activity in whole blood and lymphocytes, together with high levels of serum immunoglobulins and cytokines, suggesting the involvement of cholinesterases, and in immune cell response against infection by S. schenckii. / A esporotricose é uma micose de implantação, causada pelo complexo de espécies Sporothrix spp., considerada a micose subcutânea com a maior ocorrência e importância nas Américas, esse fungo termodimórfico induz uma resposta inflamatória granulomatosa crônica em seus hospedeiros. As colinesterases, acetilcolinesterase (AChE) e butirilcolinesterase (BChE) desempenham um papel chave na sinalização de processos inflamatórios e imunes, por regular os níveis de ACh, o principal neurotransmissor da via colinérgica antiinflamatória . A atividade das colinesterases tem sido demonstrada em várias condições inflamatórias, contudo, não há evidencias de sua participação na esporotricose. O objetivo deste estudo foi relatar um caso de esporotricose felina por infecção natural; avaliar as atividades da AChE em linfócitos e no sangue total; avaliar a atividade da BChE; citocinas (IL1, IL6, TNFα, INFγ e IL10) e imunoglobulinas (IgA, IgG, IgM, IgE) no soro de ratos infectados experimentalmente por S. schenckii. Foram utilizados sessenta e três ratos distribuídos em três grupos, grupo controle (GC), grupo por infecção subcutânea (GSC) e grupo por infecção intraperitoneal (GIP). A coleta de sangue para avaliação das atividades das colinesterases, citocinas e imunoglobulinas foram realizadas nos dias 15, 30 e 40 pós-infecção (PI). No GIP, ocorreu um aumento na atividade das AChE no sangue em todos os tempos experimentais, nos linfócitos o aumento ocorreu apenas nos dias 30 e 40 dias PI. O aumento dessa enzima sugere uma diminuição nos níveis de ACh, com consequentemente aumento das IL-1, IL-6, TNFα, INFγ, como observado neste estudo. Na fase aguda da infecção deseja-se uma resposta inflamatória intensa na tentativa de eliminar o agente. Porém, com a cronicidade da infecção, se o estímulo for mantido pode acarretar marcante lesão tecidual. Com relação ao processo crônico observou no GIP, aos 30 e 40 dias PI, que a IL-10 mostrou-se aumentada, porém não sendo suficiente para conter a inflamação, pois as citocinas pró, continuaram com altos níveis. Inversamente o que aconteceu no GIP, o grupo SC obteve níveis reduzidos de IL 10 em todos s tempos PI, este decréscimo pode levar a danos teciduais pelo não bloqueio da resposta inflamatória. A atividade da AChE, no GSC só se mostrou estatisticamente aumentada nos linfócitos, aos 40 dias PI. Não houve atividade estatística significativa ao avaliar a BChE, em ambos os grupos, exceto no GSC 40 dias PI. A BChE não é eficiente em hidrolisar ACh em baixas concentrações, mas ela pode substituir a AChE na hidrolise da ACh quando a mesma estiver inibida. Os altos níveis evidenciados das imunoglobulinas em ambos os grupos e em todo os tempos, demonstra a indução da resposta imune humoral na esporotricose. Assim, o aumento na atividade da AChE em sangue total e em linfócitos, juntamente com os elevados níveis de citocinas e imunoglobulinas séricas, sugere-se o envolvimento dessa colinesterase, na resposta imune e celular frente a infecção por S. schenckii.
164

AVALIAÇÃO, IN VITRO, DOS PARÂMETROS CINÉTICOS DA ENZIMA ACETILCOLINESTERASE CEREBRAL DE RATOS FRENTE A ALGUNS COMPOSTOS AZÓIS / IN VITRO EVALUATION OF THE KINETIC PARAMETHERS OF THE CEREBRAL ACETYLCHOLINESTERASE ENZYME FROM RATS FACE TO SOME AZOLIC COMPOUNDS

Serres, Jonas Daci da Silva 09 September 2011 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The acetylcholinesterase enzyme is responsible for the acetylcholine hydrolisis in the synaptic cleft during the transmission of nervous impulse. The investigation of new inhibitors of this important enzyme is very relevant on tentative to minimize the effects due damages on cholinergic transmission, mainly in pathologies as Alzheimer s disease. Therefore, this work has investigated the inhibitory potencial of different classes of heterocyclic compounds (pyrazole, isoxazole and isoxazolinone), in vitro, on the acetylcholinesterase activity on different cerebral structures of rats (cortex, striatum and hippocampus). Among all tested compounds, only the 2c compound did not show any inhibition; all the remaining compounds showed significative inhibition (p<0,05), and the compounds 2a and 3c, that shown the best inhibitory efficacy (51 and 59 %, respectively), were the compounds selected to the kinetic enzimatic assays. From these results it was possible to characterize the kinetic parameters (Km and VMAX) and the inhibition type showed by every compound through the Lineweaver-Burk and Cornish-Bowden plots. The mentioned parameters to the compound 2a were Km = 0.2 mM and VMAX = 7.94 μmoles ASCh/h/mg of protein. The compound exihibited a competitive inhibition type with Ki = 1.46 mM. To the compound 3c, the values of Km and VMAX were 0.05 and 1.42 μmoles ASCh/h/mg of protein, respectively. This compound performed a noncompetitive inhibition type with Ki = 2.2 mM. All the compounds were previously diluted in methanol PA in concentrations of 0.031 mM, 0.0625 mM, 0.125 mM, 0.250 mM and 0.500 mM. The inhibitors selected to the kinetic assays were also diluted in methanol PA in the concentrations of 0.125, 0.250, 0.500 and 1.0 mM. / A enzima acetilcolinesterase é responsável pela hidrólise de acetilcolina na fenda sináptica durante a transmissão do impulso nervoso. A investigação de novos inibidores dessa importante enzima é de grande relevância na tentativa de minimizar os efeitos causados por danos na transmissão colinérgica, principalmente em patologias como a doença de Alzheimer. Frente a isto, este trabalho investigou o potencial inibitório de diferentes classes de compostos heterocíclicos (pirazóis, isoxazóis e isoxazolinonas), in vitro, sobre a atividade da enzima acetilcolinesterase de diferentes estruturas cerebrais de ratos (córtex, estriado e hipocampo). Dos onze compostos testados, apenas o denominado aqui como 2c, foi o único a não apresentar inibição significativa da enzima em nenhuma estrutura testada; todos os dez compostos restantes apresentaram inibição significativa (p< 0,05), sendo que os compostos 2a e 3c, por possuírem maior eficácia inibitória (53 e 59%, respectivamente) foram os compostos selecionados para os ensaios de cinética enzimática. A partir destes ensaios foi possível a caracterização dos parâmetros cinéticos (Km e VMÁX) e do tipo de inibição apresentada por cada composto através da plotagem dos dados em gráficos de Lineweaver-Burk e Cornish-Bowden, sendo que os parâmetros citados encontrados para o composto 2a foram: Km = 0,2 mM e VMÁX = 7,94 μmoles ASCh/h/mg de proteína. O composto apresentou inibição competitiva com um Ki = 1,46 mM. Já o composto 3c apresentou valores de Km e VMÁX iguais a 0,05 mM e 1,42 μmoles ASCh/h/mg de proteína, respectivamente. A inibição exercida por este composto foi do tipo não-competitiva com Ki = 2,2 mM. Todos os compostos foram diluídos em metanol PA, nas concentrações de 0,031; 0,062; 0,125; 0,250 e 0,500 mM. Os compostos selecionados para os ensaios de cinética enzimática foram diluídos também em metanol PA, nas concentrações de 0,125; 0,250; 0,500 e 1,0 mM.
165

Design, synthesis and biological evaluation of novel uncharged bifunctional hybrid reactivators for organophosphorus nerve agent-inhibited human acetylcholinesterare / Design, synthèse et évaluation biologique de nouveaux réactivateurs de l'Acétylcholinestérase humaine empoissonnée par des agents neurotoxiques organophosphorés

Sousa, Julien de 08 December 2015 (has links)
Ce projet à caractère dual civil et militaire vise à développer de nouvelles contre-mesures médicales d’urgences hautement efficaces en cas d’intoxications accidentelles ou volontaires aux organophosphorés toxiques (gaz de combat et pesticides). Ces poisons agissent comme des inhibiteurs irréversibles de l’acétylcholinestérase, enzyme clé principalement localisé dans notre système nerveux, par phosphorylation du site actif enzymatique. Cependant, un nucléophile puissant capable de pénétrer jusqu’au site actif de la protéine peut également l’hydrolyser. Notre recherche réside sur l’élaboration de molécules hybrides possédant deux systèmes clés : une partie réactivatrice neutre capable de restaurer l’activité enzymatique et un ligand du site périphérique capable de vectoriser la structure hybride à l’entrée du site actif. Une librairie de nouveaux hybrides bifonctionnels a ainsi été synthétisée, évaluée et décrite dans ces travaux de thèse. L’ensemble de ces hybrides démontre une activité égale ou supérieure à celle des réactivateurs de référence. Nous avons même découvert le premier hybride universel surpassant l’activité de réactivation des antidotes actuellement commercialisés pour des intoxications aux gaz de combat et aux pesticides. / Remediation of both acute and chronic intoxications by organophosphorus nerve agents, both chemical warfare agents and pesticides, continues to be a challenge of paramount importance. These manmade poisons act as covalent and irreversible inhibitors of acetylcholinesterase, a key enzyme mostly located in the nervous system, through phosphylation of its active site. The phosphylated active site residues do not undergo spontaneous hydrolysis. However, hydrolysis can be achieved through the use of strong nucleophiles able to enter the buried active site of the protein. Our research is based on the rational design of hybrid structures containing two key elements: a neutral reactivator to restore the enzyme activity, and a peripheral site ligand giving selectivity by targeted binding to a site at the entrance of the enzyme active site gorge. A library of novel reactivators based on acridine, quinoline and original oxoassoanine analogues was synthesised, evaluated and is herein described. Delightfully, most of these hybrids proved to be equally or more potent than the drugs currently in use. Outstandingly, we have discovered the first broad-spectrum reactivator that outperformed all known reactivators for both chemical warfare agent and pesticide intoxications.
166

Efeito da curcumina sob a atividade das enzimas ntpdase e acetilcolinesterase em linfócitos de ratos expostos à fumaça do cigarro / Effect of curcumin in the ntpdase and acetylcholinesterase activity in cigarette smoke exposed rats

Jaques, Jeandre Augusto dos Santos 19 August 2010 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The exposure to the cigarette smoke xenobiotics is related with a compromised immune system and the development of many diseases such as Chronic Obstructive Pulmonary Disease (COPD) and lung cancer. The NTPDase and acetylcholinesterase (AChE) are important enzymes involved in the regulation of immune system and alterations in their activities have been showed in many diseases including the related with cigarette smoke-exposure. The curcumin (Cur), polyphenol isolated from the rhizomes of Curcuma longa and widely employed in the culinary and oriental traditional medicine, has many biological activities such as antioxidant, anticarcinogenic and antiinflammatory. Considering the relevance of lymphocytes in the establishment and progression of immune responses, the purpose of this study was to evaluate the effect of curcumin in the NTPDase and AChE activities in peripheral lymphocytes (PL) and lung lymphocytes (LL) from rats exposed to cigarette smoke. The establishment of a protocol to lung lymphocytes separation using the lung tissue was performed with the objective of optimize the cellular viability and the purity of separation, using as references the protocols for separation of human peripheral and lung lymphocytes. The experimental procedure to evaluate the effect of curcumin on the NTPDase and AChE in lymphocytes from rats exposed to the cigarette smoke was divided in two sets of experiments. In the first set, the animals were randomly divided into four groups: Vehicle; Cur 12.5 mg/kg; Cur 25 mg/kg; Cur 50 mg/kg. In the second experimental set, the animals were divided into 5 groups: Vehicle; smoke exposed; smoke and Cur 12.5 mg/kg; smoke and Cur 25 mg/kg; smoke and Cur 50 mg/kg. Curcumin was diluted with corn oil, administered by oral gavage, not exceeding 1 ml/kg body weight. The treatment with curcumin and cigarette smoke was carried out once a day, 5 days each week, during 30 days. It was administered the curcumin or corn oil, and approximately 10 minutes later, the smoking groups were exposed to the sidestream smoke of four commercial cigarettes (nicotine 0.9 mg, tar 10 mg each) inside a whole-body smoke exposure chamber. Control animals were placed in an equal chamber for the same amount of time. After thirty days, the animals were euthanized, the lung was removed and the peripheral blood collected for separation of lymphocytes. With the standardization of the protocol to the separation of lung lymphocytes it was achieved a percentage of lymphocytes higher than 82% and it was observed a strong correlation between the enzyme activity using ATP and ADP as substrates, which indicates that the results can be expressed in milligram of protein, millions of cells and millions of viable cells. The results from the experiments with the cigarette smoke exposure demonstrated that the treatment with curcumin prevented the alterations observed in the cigarette smoke-exposed animals such as the decrease of ATP and ADP hydrolysis in PL and LL, and the increase of AChE activity in PL. We suggest that the treatment with curcumin was protective, since the high concentrations of ATP are positively related with inflammation and tissue damage, and the emphysematous damages observed in cigarette smoke-exposed was not observed in the groups treated with curcumin. / A exposição aos xenobióticos da fumaça do cigarro está relacionada com o comprometimento do sistema imune e o desenvolvimento de diversas doenças como a Doença Pulmonar Obstrutiva Crônica (DPOC) e câncer de pulmão. A NTPDase e a acetilcolinesterase (AChE) são importantes enzimas envolvidas na regulação do sistema imune e alterações nas suas atividades tem sido descritas em várias doenças incluindo as relacionadas à exposição à fumaça do cigarro. A curcumina (Cur), polifenol obtido a partir de rizomas de Curcuma longa e amplamente utilizado na culinária e na medicina tradicional oriental, possui muitas atividades biológicas como antioxidante, anticarcinogênica e antiinflamatória. Tendo em vista a relevância dos linfócitos no estabelecimento e progressão de respostas imunes, o objetivo deste estudo foi avaliar o efeito da curcumina na atividade das enzimas NTPDase e AChE em linfócitos periféricos (PL) e linfócitos pulmonares (LL) de ratos expostos à fumaça do cigarro. A padronização da separação dos linfócitos a partir de tecido pulmonar foi realizada com o objetivo de otimizar a viabilidade celular e a pureza da separação, utilizando-se como base os protocolos de separação de linfócitos periféricos e pulmonares de seres humanos. Os procedimentos experimentais para a avaliação do efeito da curcumina sob a atividade das enzimas NTPDase e AChE em linfócitos de ratos expostos à fumaça do cigarro foram divididos em duas etapas. Primeiramente, os animais foram divididos aleatoriamente em quatro grupos: veículo; Cur 12.5 mg/kg, Cur 25 mg/kg; Cur 50 mg/kg. Na segunda etapa experimental os animais foram divididos aleatoriamente em cinco grupos: veículo; cigarro; cigarro e Cur 12.5 mg/kg; cigarro e Cur 25 mg/kg; cigarro e Cur 50 mg/kg. A curcumina foi diluída em óleo de milho, administrada por gavagem oral, não excedendo 1 ml/kg de massa corpórea. O tratamento com a curcumina e com a fumaça do cigarro foi realizada uma vez por dia, cinco dias por semana, durante trinta dias. A curcumina foi administrada e, após aproximadamente dez minutos, os grupos fumantes eram expostos à fumaça de quatro cigarros comerciais (0,9 mg nicotina, 10 mg alcatrão cada) dentro de uma câmara de exposição. Os animais não expostos à fumaça do cigarro foram colocados em uma câmara equivalente, pelo mesmo período. Após trinta dias, os animais foram eutanasiados, os pulmões removidos e o sangue periférico coletado para a separação dos linfócitos. Com a padronização da técnica para a separação de linfócitos pulmonares foi obtido um percentual de linfócitos superior a 82% e ainda observou-se uma forte correlação entre a atividade da enzima usando ATP e ADP como substrato o que indica que os resultados podem ser expressos tanto em miligramas de proteína, quanto em milhões de células quanto em milhões de células viáveis. Os resultados dos experimentos com a fumaça do cigarro demonstraram que o tratamento com a curcumina preveniu as alterações observadas nos animais expostos à fumaça do cigarro como a diminuição na hidrólise de ATP e ADP em PL e LL, e o aumento da atividade da AChE em PL. Analisando os resultados obtidos, sugere-se que o tratamento com a curcumina foi protetor, uma vez que as altas concentrações de ATP estão positivamente relacionadas com inflamação e dano tecidual, e as lesões enfisematosas observadas no grupo exposto à fumaça do cigarro não foram observadas com os tratamentos com a curcumina.
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Alkaloidy Papaver rhoeas L. (Papaveraceae) a jejich biologická aktivita vztažená k Alzheimerově chorobě I. / Alkaloids of Papaver rhoeas L. (Papaveraceae) and their biological activity related to Alzheimerʼs disease I.

Bulvová, Leontina January 2017 (has links)
Bulvová, L.: Alkaloids of Papaver rhoeas L. (Papaveraceae) and their biological activity related to Alzheimerʼs disease I. Diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology, Hradec Králové 2017. The aim of this study was to process the summary alkaloidal extract of aerial parts of Papaver rhoeas L.; to isolate contained alkaloids using chromatographical methods; to identify them and to determine their inhibitory activity towards human enzymes acetylcholinesterase, butyrylcholinesterase and prolyloligopeptidase. Two alkaloids (+)-rhoeagenine and LB-2 were isolated, and the structure of LB-2 (its absolute configuration) is being determined nowadays. In vitro biological assays of these alkaloids found the following results: (+)-rhoeagenine (IC50 AChE ˃ 1000 μM, IC50 BuChE = 230 ± 10 μM, IC50 POP = 878 ± 45 μM) and LB-2 (IC50 AChE ˃ 1000 μM, IC50 BuChE = 314 ± 13 μM, IC50 POP = 706 ± 2 μM). The determined IC50 values of isolated alkaloids were compared with inhibitory standards of cholinesterases galanthamine (IC50 AChE = 1,71 ± 0,065 μM, IC50 BuChE = 42,30 ± 1,30 μM), huperzine A (IC50 AChE = 0,033 ± 0,001 μM, IC50 BuChE > 1000 μM, IC50 POP > 1000 μM) and rivastigmine (IC50 AChE = 0,037 ± 0,001 μM, IC50 BuChE = 0,0033 ± 0,0003...
168

Alkaloidy Papaver rhoeas L. (Papaveraceae) a jejich biologická aktivita vztažená k Alzheimerově chorobě II. / Alkaloids of Papaver rhoeas L. (Papaveraceae) and their biological activity related to Alzheimerʼs disease II.

Čakurdová, Marta January 2017 (has links)
Čakurdová, M.: Alkaloids of Papaver rhoeas L. (Papaveraceae) and their biological activity related to Alzheimer's disease II. Diploma thesis, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology, Hradec Králové, 2017. The aim of this work was focused on isolation of alkaloids from the fraction 1 (joined fractions 20-27), which was obtained from the summary alkaloid extract of Papaver rhoeas L. (Papaveraceae). The alkaloids were identified by structural analysis NMR, GC-MS, optical activity and melting point. Two alkaloids were identified as (-)-stylopine and (+)-rhoeadine. Isolated substances were tested on ability to inhibit the enzymes acetylcholinesterase, butyrylcholinesterase and prolyloligopeptidase. Obtained data were expressed as IC50 values: (-)-stylopine (IC50 AChE = 522 ± 67 µM, IC50 BuChE = >1000 µM, IC50 POP = >790 µM); (+)-rhoeadine (IC50 AChE = 915 ± 64 µM, IC50 BuChE = >1000 µM, IC50 POP = >790 µM). None of the isolated substances showed so potent cholinesterase inhibitory activity as the alkaloids galanthamine (IC50 AChE = 1.71± 0.065 µM, IC50 BuChE =42.30 ± 1.30 µM) and huperzine A (IC50 AChE = 0.033 ± 0.001 µM, IC50 BuChE = >1000 µM) or rivastigmine (IC50 AChE = 0.037 ± 0.001 µM, IC50 BuChE = 3.3 ± 0.3 nM)....
169

Magnetické částice jako reverzibilní nosič pro enzymové elektrody / Magnetic particles as a reversible carrier for enzyme electrodes

Janíček, Zdeněk January 2012 (has links)
Master’s thesis contains information about the enzymes, biosensors, enzyme biosensors and magnetic particles. Cholinesterasa (ChE) is the generally name for the two related enzymes, mutually differing appearance and biological functions. Acetylcholinesterasa (AChE) is necessary for the transmission of nervous excitement. AChE is located at cholinergic synapses, where is the hydrolysis of the neurotransmitter acetylcholine and this termination by the nervous excitement. Butyrylcholinesterasa (BChE) is related to AChE and it is present in serum. Experimental part was focused on electrochemical biosensors with cholinesterase enzyme using magnetic particles for reversible reconstruction layer. Cholinesterase immobilization was carried out on the magnetic particles by covalent binding after glutaraldehyde activated. The measurement of activity take place with acetylthiocholin as a substrate in a flow system, magnetic particles were captured before the platinum electrode and produced by thiocholin is detected amperometric. The aim was to measure inhibition of AChE. Significant inhibition ChE is caused by certain drugs and pesticides based on organophosphates. There was tested by inhibition of AChE pesticide dichlorvos. Emphasis was on finding possible experimental conditions for the creation of the automated procedure to measure the AChE activity, which was based on auto-injector and pumps of Gilson, together with a 735 programme for the definition of the working configuration, preparation of measurement scripts and implementation of application methods.
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Demenzspezifische medikamentöse Behandlung mit Acetylcholinesterase-Hemmern und Memantine – Unter- und Fehlversorgung?

Nürnberg, Ingo Maximilian 06 December 2017 (has links)
Rezente Studien zur Versorgung von Patienten mit Antidementiva deuten auf deutliche Defizite hin. Ziel der vorliegenden Untersuchung war die Erfassung der leitliniengerechten bzw. zulassungsübergreifenden Versorgung mit Acetylcholinesterase-Hemmern (AChEI) und Memantine bei hausärztlich betreuten Alzheimer- bzw. Demenzpatienten. Des Weiteren sollten Determinanten auf ihre Assoziation mit einer Einnahme/Verschreibung von Antidementiva identifiziert werden. Die vorliegende Untersuchung basiert auf Daten, welche im Rahmen der prospektiven longitudinalen AgeCoDe-Studie (German Study on Aging, Cognition and Dementia in Primary Care Patients) erfasst wurden. Die Datenerhebung erfolgte an 6 Studienzentren über 5 Follow-up Perioden (FUP). Insgesamt wurde der Verlauf von 3.327 initial demenzfreien Patienten über 5 Follow-up Perioden zwischen Januar 2003 (Basisdokumentation) bis November 2012 (FUP-5) untersucht. Patienten die innerhalb dieser Zeit eine Alzheimer- bzw. Demenzdiagnose erhielten wurden im Hinblick auf ihre medikamentöse Versorgungssituation analysiert. Eine leitliniengerechte medikamentöse Therapie erfolgte bei 12,4% (AChEI) und 4,8% (Memantine) der inzidenten AD-Patienten bzw. bei 12,1% (AChEI) und 3,9% (Memantine) der inzidenten Demenzpatienten. Innerhalb der einzelnen FUP erfolgte eine leitliniengerechte medikamentöse Therapie bei 8,8 - 22,6% (AChEI) und 7,7 - 14.8% (Memantine) der prävalenten AD-Patienten bzw. bei 7,4 - 21,2% (AChEI) und 8,8 - 13,4% (Memantine) der prävalenten Demenzpatienten. Die Off-Label Therapie mit AChEI bei prävalenten Patienten mit schwerer Krankheitsausprägung konnte bei 8 - 29,2% der AD-Patienten und 6,9 - 25% der Demenzpatienten festgestellt werden. Fehlbehandlungen mit Memantine bei inzidenten Patienten mit leichtem Schweregrad ließen sich bei 4,4% der AD-Patienten und 3,8% der Demenzpatienten feststellen. Bei prävalenten Patienten lag eine Fehlbehandlung mit Memantine innerhalb des Untersuchungszeitraums bei 3,3 - 9,3% der AD-Patienten und 2,6 - 7,4% der Demenzpatienten vor. Anhand der Daten kann festgestellt werden, dass die Einnahme von AChEI mit einem höheren Alter sowie schlechteren MMSE-Werten assoziiert ist. Eine Einnahme von Memantine ist mit einem höheren Bildungsstand, schlechteren MMSE bzw. IADL-Werten assoziiert. Es konnte gezeigt werden, dass eine leitliniengerechte medikamentöse Therapie mit AChEI und Memantine bei hausärztlichen Alzheimer- und Demenzpatienten nur im geringen Umfang erfolgt. Fehlbehandlungen mit Memantine konnten nur bei einem gleichbleibend geringen Anteil der Patienten mit leichtem Demenzschweregrad nachgewiesen werden.:Inhaltsverzeichnis Abkürzungsverzeichnis III Abbildungsverzeichnis V Tabellenverzeichnis IX 1 Einleitung 1 2 Stand der Forschung 3 2.1 Formen der Demenzerkrankung und aktuelle Klassifikationssysteme 3 2.2 Demenzspezifische Medikation 9 2.3 Versorgungssituation mit demenzspezifischer Medikation 15 3 Fragestellung 20 4 Material und Methoden 21 4.1 Stichprobenbeschreibung und Studiendesign 21 4.2 Befragung der Studienteilnehmer, Befragung der Angehörigen und Hausärzte 23 4.2.1 Instrumente zur Erfassung der kognitiven Leistung und der Alltagskompetenz 23 4.2.2 Definition der milden kognitiven Beeinträchtigungen 25 4.2.3 Definition der Demenz und der Demenz-Schweregrade 25 4.2.4 Erfassung der Medikation 26 4.2.5 Soziodemographische Merkmale 27 4.3 Datenanalyse 28 5 Ergebnisse 30 5.1 Schweregradspezifische medikamentöse Therapie bei inzidenten Alzheimer- und Demenzpatienten 33 5.2 Schweregradspezifische medikamentöse Therapie bei prävalenten Alzheimer- und Demenzpatienten 41 5.3 Medikamentöse Therapie bei nicht-dementen Patienten 47 5.4 Determinanten einer medikamentösen Therapie. 51 6 Diskussion 63 6.1 Studienpopulation 63 6.2 Antidementive Therapie bei inzidenten und prävalenten Alzheimer- und Demenzpatienten 65 6.3 Antidementive Therapie bei nicht-dementen Patienten 69 6.4 Determinanten einer antidementiven Behandlung 70 6.5 Stärken und Limitationen der Studie 72 7 Schlussfolgerung 75 Zusammenfassung der Arbeit 76 Literaturverzeichnis 78 Anlagen 86 Cox-Regressionsanalyse für Acetylcholinesterase-Hemmer 86 Cox-Regressionsanalyse für Memantine 87 Ethikvotum 88 Erklärung über die eigenständige Abfassung der Arbeit 89 Lebenslauf 90 Danksagung 91

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