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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.
61

Influência da rutina na fotoestabilização da avobenzona (filtro UVA) e do ρ-metoxicinamato de octila (filtro UVB) / Influence of rutin in photostabilization of avobenzone (UVA filter) and octyl methoxycinnamate (UVB filter)

Pinto, Claudinéia Aparecida Sales de Oliveira 29 May 2014 (has links)
Com o intuito de promover proteção de amplo espectro, na maioria dos protetores solares estão associados pelo menos dois filtros orgânicos (UVA e UVB). A combinação da avobenzona (BMBM), filtro UVA, e do p--metoxicinamato de octila (EHMC), filtro UVB, é conhecida e muito utilizada em formulações manipulas e industrializadas, porém apresenta alteração na absorção espectral após exposição à radiação UV. A estratégia empregada com maior frequência para reduzir a instabilidade da combinação é baseada na adição de agentes fotoestabilizadores. A adição de substâncias naturais em formulações fotoprotetoras vem sendo explorada, especialmente o grupo dos flavonoides, como a rutina, que apresenta resultados positivos em relação à eficácia fotoprotetora. O objetivo principal desta pesquisa foi avaliar o potencial da rutina como substância fotoestabilizadora dos filtros EHMC e BMBM. Foram desenvolvidas formulações contendo os dois filtros associados ou não com rutina de acordo planejamento fatorial em três níveis. As formulações foram avaliadas quanto a eficácia fotoprotetora in vitro aplicadas em placas de PMMA e analisadas por espectrofotometria de refletância com esfera de integração antes e após a exposição à radiação UV. As interações moleculares dos filtros com a rutina foram avaliadas por 1H RMN, DSC, TG e análise qualitativa da supressão do estado energético singleto. A adição de rutina nas formulações contendo 5,0% (p/p) de BMBM e 10,0% (p/p) de EHMC promoveu elevação na conservação do FPS in vitro de 53,9% para 65,8 (0,1% de rutina) e 70,8% (1,0% de rutina). As curvas DSC e TG da rutina apresentaram alterações promovidas pela presença dos filtros BMBM e EHMC, indicando interação entre o flavonoide e os filtros. Após dose de 5760 J cm-2 de radiação UV o valor da razão trans/cis para o filtro EHMC em solução adicionado do filtro BMBM foi elevado de 5,5±0,1, sem adição de rutina, para 12,6±0,4, com adição da rutina. A análise qualitativa da supressão do estado singleto indicou que um dos mecanismos envolvidos na fotoestabilização dos filtros BMBM e EHMC é a supressão do estado energético singleto. Os resultados reportados neste estudo indicaram que a adição da rutina em formulações fotoprotetoras representa um caminho simples e efetivo para elevar a fotoestabilidade da combinação dos filtros BMBM e EHMC. A adição da rutina em formulações fotoprotetoras representa uma estratégia promissora, pois aliada a ação fotoestabilizadora, verificada nesse estudo, esse flavonoide possui propriedades antioxidante e quelante de metais que podem colaborar para o desenvolvimento de formulações fotoprotetoras de amplo espectro com aumento da segurança e eficácia. / In order to promote broad-spectrum protection, most sunscreens are associated with at least two organic filters (UVA and UVB). The combination of avobenzone (BMBM), UVA filter, and octyl methoxycinnamate (EHMC), UVB filter, is well known and widely used in industrial formulations and pharmaceutical compounding, but shows alteration in spectral absorption after UV radiation exposure. The most commonly used strategy to reduce the instability of the combination is based on the addition of photostabilizer agents. The addition of natural substances in sunscreen formulations has been explored, especially the group of flavonoids such as rutin, which shows positive results regarding photoprotective efficacy. The main objective of this research was to evaluate the potential of rutin as a photostabilizer substance of EHMC and BMBM. Formulations were developed containing the two filters associated or not with rutin, according to factorial design at three levels. The formulations were evaluated for in vitro photoprotective efficacy applied on PMMA plates and analyzed by spectrophotometer with integrating sphere reflectance before and after exposure to UV radiation. Molecular interactions of filters with rutin were evaluated by 1H NMR, DSC, TG and qualitative analysis of the suppression of singlet energy state. The addition of rutin in the formulations containing 5.0 % (w/w) BMBM and 10.0 % (w/w) EHMC promoted an increase in the preservation of in vitro SPF of 53.9% to 65.8 (0.1 % rutin) and 70.8 % (1.0% rutin). The DSC and TG curves of rutin showed changes promoted by the presence of BMBM and EHMC filters, indicating interaction between the flavonoid and filters. After 5760 J cm-2 of UV radiation the value of the trans/cis ratio for the EHMC filter added from the BMBM filter was increased from 5.5 ± 0.1 without addition of rutin, to 12.6 ± 0 4,with the addition of rutin. Qualitative analysis of the suppression of the singlet state indicated that one of the mechanisms involved in the photostabilization BMBM and EHMC filters is suppression of singlet excited state.The results reported in this study indicate that the addition of rutin in sunscreen formulations is a simple and effective way to increase the photostability of the combination of BMBM and EHMC. The addition of rutin in sunscreen formulations represents a promising strategy, for allied with the photostabilization action, observed in this study, this flavonoid has antioxidant and chelating properties of metals that can contribute to the development of broad-spectrum sunscreens formulations with increased safety and efficacy.
62

ESTUDO DA ASSOCIAÇÃO ENTRE HESPERIDINA E ANFOTERICINA EM DANOS HEPÁTICO E RENAL E NAS OXIDAÇÕES BIOQUÍMICAS

Manente, Francine Alessandra 18 February 2013 (has links)
Made available in DSpace on 2017-07-21T14:13:09Z (GMT). No. of bitstreams: 1 Francine Alessandra Manente.pdf: 1212792 bytes, checksum: 5c5b36ad0ca624ee36b65879663b0362 (MD5) Previous issue date: 2013-02-18 / Amphotericin B (AmB) is drug "gold standard" for the treatment of invasive fungal infections since 1960. However, amphotericin B has high toxicity, which manifests itself most commonly in the kidneys (nephrotoxicity) and less frequently in the liver (liver toxicity). It is known since 1985 that self-oxidation of amphotericin B gives different forms of reactive oxidative species and these are responsible in part by toxicity. An antioxidant, such as hesperidin and rutin, could contribute, through the reduction of oxidative stress, and to protect against renal injury generated by ischemia. This fact and the involvement of amphotericin B in the generation of free radicals make it interesting to evaluate the effect of hesperidin, rutin and amphotericin B (alone or associated) against reactive oxygen species and free radicals, as well as the study of the same models in toxicity . In testing the antifungal combination with hesperidin showed synergism. In tests oxidative systems, opposite the ABTS+, the hesperidin showed IC50= 0,0044mg/mL, rutin IC50=0,0023mg/mL and amphotericin B IC50=0,0124mg/mL (isolated), IC50=0,0003mg/mL (associated with hesperidin) and IC50=0,0014mg/mL (associated with rutin). In the DPPH assay only rutin was action. Front HOCl, hesperidin showed IC50=0,0109, rutin IC50=0,0025 and amphotericin B showed IC50=0,0056 (isolated) IC50=0,0023mg/mL (associated with hesperidin) and IC50=0,0036 (associated with rutin). In the trial with O2 the samples were not effective. In inhibition kinetics MPO/H2O2/Guaiacol only rutin promote inhibition. Front to erythrocytes, amphotericin promoted lysis in a dose-dependent manner. HUVEC cells using the associations decreased cell viability. However, in the toxicity test with Artemia salina associated samples were able to lower the toxicity of amphotericin B. To conclude, in tests with animals amphotericin B caused leukopenia, monopenia generated and renal damage, which can be reversed using hesperidin in combination. With these results, we suggest that the combination of a natural product with amphotericin B could decrease the toxicity caused by this antinfúngico, and concomitant use could be promising. / A anfotericina B (AmB) é fármaco "padrão ouro" para o tratamento de infecções fúngicas invasivas desde 1960. Entretanto, a anfotericina B apresenta elevada toxicidade, que se manifesta mais freqüentemente nos rins (nefrotoxicidade) e com menor frequência no fígado (hepatotoxicidade). É sabido, desde 1985, que a auto-oxidação da anfotericina B origina diferentes formas de espécies reativas oxidativas e estas seriam responsáveis, em parte, pela toxicidade. Agentes antioxidantes, tais como a hesperidina e rutina, poderiam contribuir, por meio do decréscimo do estresse oxidativo, para a proteção renal e contra a injúria gerada pela isquemia. Tal fato e o envolvimento da anfotericina B na geração de radicais livres tornam interessante a avaliação do efeito da hesperidina, rutina e anfotericina B (isoladamente ou associadas) frente a espécies reativas do oxigênio e radicais livres, bem como o estudo das mesmas em modelos de toxicidade. No teste antifúngico a associação com a hesperidina mostrou sinergismo. Nos testes em sistemas oxidativos, frente ao ABTS+, a hesperidina apresentou IC50= 0,0044mg/mL, a rutina IC50=0,0023mg/mL e a anfotericina B IC50=0,0124mg/mL (isolada), IC50=0,0003mg/mL (associada à hesperidina) e IC50=0,0014mg/mL (associada à rutina). No ensaio do DPPH apenas a rutina mostrou ação. Frente ao HOCl, a hesperidina apresentou IC50=0,0109, a rutina IC50=0,0025 e a anfotericina B apresentou IC50=0,0056 (isolada), IC50=0,0023mg/mL (associada com a hesperidina) e IC50=0,0036 (associada com a rutina). No ensaio com o O2 - as amostras não foram efetivas. Na inibição da cinética da MPO/H2O2/Guaiacol somente a rutina promoveu inibição. Frente aos eritrócitos, a anfotericina promoveu lise de modo dose-dependente. Utilizando as células HUVEC, as associações diminuíram a viabilidade celular. Entretanto, no ensaio de toxicidade com a Artemia salina as amostras associadas foram capazes de diminuir a toxicidade da anfotericina B. Para finalizar, nos testes com os animais a anfotericina B causou leucopenia, monopenia e gerou dano renal, o qual pode ser revertido utilizando a hesperidina em associação. Com estes resultados pode-se sugerir que a associação de um produto natural com a anfotericina B poderia diminuir a toxicidade causada por este antinfúngico, sendo que sua utilização concomitante poderá ser promissora. Palavras-chave: hesperidina, anfotericina B, rutina, estresse oxidativo, citotoxicidade, nefrotoxicidade.
63

Anestesisjuksköterskors erfarenheter av postoperativ smärtlindring av barn : En kvalitativ intervjustudie / Anesthesia nurses experiences of giving postoperative pain relief to children : A qualitative interview study

Dobrin, Leif, Wall, Niklas January 2009 (has links)
<p><strong>Bakgrund:</strong> Att förebygga, bedöma och behandla smärta är centralt i anestesisjuksköterskans arbete. Barns upplevelser och uttryckssätt vid smärta skiljer sig mycket från vuxnas. Det är därför en stor utmaning för anestesisjuksköterskor att tolka barns uttryck och känslor för att förstå barnet och kunna erbjuda trygghet och smärtlindring. Forskning har visat att barns postoperativa smärta underbehandlas, trots att kunskaperna om barns smärta ökat. Genom att belysa anestesisjuksköterskans upplevelser kan förståelsen för vad som bidrar till en god respektive mindre god postoperativ smärtlindring av barn öka.</p><p><strong>Syfte:</strong> Syftet med denna studie var att beskriva anestesisjuksköterskors erfarenheter i samband med postoperativ smärtlindring av barn.</p><p><strong>Metod:</strong> Semistrukturerade intervjuer genomfördes med åtta anestesisjuksköterskor från ett svenskt länssjukhus i mellersta Norrland.  Insamlad data analyserades med manifest innehållsanalys.</p><p><strong>Resultat:</strong> Utifrån analysen framkom tre kategorier och sju subkategorier. De tre kategorierna var: Att skapa kontakt är en utmaning, Helhetstänkande och Rutiner.  Det var en utmaning för anestesisjuksköterskan att skapa kontakt med ett barn som varit sövd. Det var viktigt att alla personalgrupper samt föräldrar samarbetade, och den egna erfarenheten var den viktigaste källan till kunskap samt att det fanns brister gällande skriftliga rutinbeskrivningar.Diskussion: Det är viktigt att det finns tydliga rutiner som underlättar smärtlindringen av barn postoperativt och barn bör bedöma den egna smärtan i så stor utsträckning som möjligt. Det var viktigt att ha en god planering t.ex. att påbörja smärtlindringen tidigt. Stress och oro innan operation kunde ge effekter långt tid efter. Föräldrarna var viktiga och skall involveras i vården för att vara ett stöd för sitt barn. Barn kan reagera kraftigt på anestesiläkemedel och därför bör de väckas långsamt och under lugna förhållanden.</p> / <p><strong>Background:</strong> To prevent, assess and treat pain is central to anesthesia nurses work. Children's experiences and expression of pain are very different from adults. It is therefore a major challenge for anesthesia nurses to interpret children's expressions and emotions in order to understand the child, and to offer security and pain relief. Research has shown that children's postoperative pain is undertreated, despite that the knowledge of children's pain has increased. By highlighting anesthesia nurses’ experiences the understanding may increase concerning factors that contributes to a good or not so good postoperative pain relief in children.</p><p><strong>Objective:</strong> The purpose of this study was to describe anesthesia nurses' experiences when caring for children with a need of postoperative pain relief.</p><p><strong>Method:</strong> Semi-structured interviews were carried out with eight anesthesia nurses at a county hospital in the north central part of Sweden. Collected data was analyzed with a manifest content analysis.</p><p><strong>Results:</strong> From the analysis three categories and seven sub-categories emerged. The three categories were: To create communication is a challenge, Holistic thinking and Routines.  It was a challenge for the anesthesia nurses to communicate with a child that has been put to sleep. It was also of importance that all healthcare staff and parents cooperated. The anesthesia nurses own experiences was the main source of knowledge and there was a shortage of written routine descriptions.Discussion: It is of importance to have clear procedures to facilitate pain relief of children postoperatively and children should assess their own pain as much as possible. To have a good planning e.g. to initiate pain relief before the operation was also of importance. Stress and anxiety before surgery may have an impact long time after the treatment was over. Parents are important and should be involved in the care so they can support their child. Children may react strongly to the anesthesia drugs and therefore they should be brought back slowly postoperatively and in calm conditions.</p>
64

Anestesisjuksköterskors erfarenheter av postoperativ smärtlindring av barn : En kvalitativ intervjustudie / Anesthesia nurses experiences of giving postoperative pain relief to children : A qualitative interview study

Dobrin, Leif, Wall, Niklas January 2009 (has links)
Bakgrund: Att förebygga, bedöma och behandla smärta är centralt i anestesisjuksköterskans arbete. Barns upplevelser och uttryckssätt vid smärta skiljer sig mycket från vuxnas. Det är därför en stor utmaning för anestesisjuksköterskor att tolka barns uttryck och känslor för att förstå barnet och kunna erbjuda trygghet och smärtlindring. Forskning har visat att barns postoperativa smärta underbehandlas, trots att kunskaperna om barns smärta ökat. Genom att belysa anestesisjuksköterskans upplevelser kan förståelsen för vad som bidrar till en god respektive mindre god postoperativ smärtlindring av barn öka. Syfte: Syftet med denna studie var att beskriva anestesisjuksköterskors erfarenheter i samband med postoperativ smärtlindring av barn. Metod: Semistrukturerade intervjuer genomfördes med åtta anestesisjuksköterskor från ett svenskt länssjukhus i mellersta Norrland.  Insamlad data analyserades med manifest innehållsanalys. Resultat: Utifrån analysen framkom tre kategorier och sju subkategorier. De tre kategorierna var: Att skapa kontakt är en utmaning, Helhetstänkande och Rutiner.  Det var en utmaning för anestesisjuksköterskan att skapa kontakt med ett barn som varit sövd. Det var viktigt att alla personalgrupper samt föräldrar samarbetade, och den egna erfarenheten var den viktigaste källan till kunskap samt att det fanns brister gällande skriftliga rutinbeskrivningar.Diskussion: Det är viktigt att det finns tydliga rutiner som underlättar smärtlindringen av barn postoperativt och barn bör bedöma den egna smärtan i så stor utsträckning som möjligt. Det var viktigt att ha en god planering t.ex. att påbörja smärtlindringen tidigt. Stress och oro innan operation kunde ge effekter långt tid efter. Föräldrarna var viktiga och skall involveras i vården för att vara ett stöd för sitt barn. Barn kan reagera kraftigt på anestesiläkemedel och därför bör de väckas långsamt och under lugna förhållanden. / Background: To prevent, assess and treat pain is central to anesthesia nurses work. Children's experiences and expression of pain are very different from adults. It is therefore a major challenge for anesthesia nurses to interpret children's expressions and emotions in order to understand the child, and to offer security and pain relief. Research has shown that children's postoperative pain is undertreated, despite that the knowledge of children's pain has increased. By highlighting anesthesia nurses’ experiences the understanding may increase concerning factors that contributes to a good or not so good postoperative pain relief in children. Objective: The purpose of this study was to describe anesthesia nurses' experiences when caring for children with a need of postoperative pain relief. Method: Semi-structured interviews were carried out with eight anesthesia nurses at a county hospital in the north central part of Sweden. Collected data was analyzed with a manifest content analysis. Results: From the analysis three categories and seven sub-categories emerged. The three categories were: To create communication is a challenge, Holistic thinking and Routines.  It was a challenge for the anesthesia nurses to communicate with a child that has been put to sleep. It was also of importance that all healthcare staff and parents cooperated. The anesthesia nurses own experiences was the main source of knowledge and there was a shortage of written routine descriptions.Discussion: It is of importance to have clear procedures to facilitate pain relief of children postoperatively and children should assess their own pain as much as possible. To have a good planning e.g. to initiate pain relief before the operation was also of importance. Stress and anxiety before surgery may have an impact long time after the treatment was over. Parents are important and should be involved in the care so they can support their child. Children may react strongly to the anesthesia drugs and therefore they should be brought back slowly postoperatively and in calm conditions.
65

Kvinnors upplevelser av brytpunkter och rutiner i karriären / Women´s experiences of Turning Points and Routines in Occupational Career

Engström, Frida January 2011 (has links)
Brytpunkter innebär skiften mellan olika sysselsättningar och områden på utbildnings- och arbetsmarknaden. För att hantera en brytpunkt använder individen olika rutiner. Syftet med studien är att studera sex kvinnors berättelser om brytpunkter och rutiner i karriären. Sex semistrukturerade intervjuer har genomförts. Vid bearbetningen och analysen av kvinnornas berättelser har en hermeneutiskt ansats använts. Resultatet visar att de sex kvinnorna har upplevt ett flertal brytpunkter i sina karriärer samt att de har använt olika rutiner för att hantera dessa brytpunkter. De flesta brytpunkter är svåra att klassificera som frivilliga eller påtvingade, samt svåra att skilja från rutiner och tidigare brytpunkter. En slutsats blir att karriär kan beskrivas som en livslång process av brytpunkter och rutiner. / Turning points involves shifts between different occupations and areas of education and labor. The individual processes turning points using various routines. The purpose of this study is to examine six women's stories of turning points and routines in their careers. Six semi structured interviews were conducted. A hermeneutic approach has been used in processing and analyzing the stories. The results show that the six women have experienced several turning points in their career and that they have used several different routines to deal with these turning points. Most turning points have been difficult to classify as self-initiated or forced, as well as difficult to distinguish from routines and previous turning points. One conclusion is that career can be described as a lifelong process of turning points and routines.
66

戈爾巴喬夫、葉爾欽、普京政治改革的比較

陳立宗 Unknown Date (has links)
本論文把論述重心放在「比較」上,試圖去認識三位國家領導人對於政治改革理念以及改革實踐的不同之處,也希望透過這樣的比較,釐清三位領導人的改革各自&#29234;俄羅斯政治體制帶來什麼不一樣的影響,以及他們各自的政治選擇又是帶領俄羅斯朝哪個方向前進。其次,我們還要釐清國家領導人的性格和意志等因素是如何影響制度運行。俄羅斯的超級總統制(Super-Presidentialism)將領導人的個人因素突出,這樣的體制對俄羅斯的民主有什麼影響。最後,本論文將探討俄羅斯獨有的政治文化是如何影響三位領導人的政治選擇和發展。 / This article’s main purpose is comparison, it tries to tell the different side of political innovation and the way it practices of 3 Russian leaders. It also clarifies the 3 leader’s reformation has been done to Russian political system separately and which direction their political decision has brought Russia into. Moreover, we will point out how the leaders’ will and personality effect the system. Super- Presidentialism of Russia highlight leader’s individual factor, what kind of effect the Super- Presidentialism does to Russian democracy. Finally, the essay will discuss how do the 3 leader’s political decision and development has been effected by Russian unique political culture.
67

Biologicky aktivní fenolické látky v drobném ovoci. / Biologically active phenolic compounds in small fruit.

LAXOVÁ, Lenka January 2017 (has links)
This master´s thesis focuses at bioactive compounds in edible berries during its culinary processing. Elderberries (Sambucus nigra L.) were selected as a representative of edible berries variety. Elderberry is known for presence of significant bioactive compound content and usage in traditional medicine. Elderberries were processed acording to common culinary recipes. Amount od selected bioactive polyphenolic compounds (chlorogenic acid, quercetin, rutin, anthocyanes) was detected accordingly. Additionally content of ascorbic acid was determined. On the basis of the experimental determination, it was found that anthocyanes and rutin are the most common compounds found in elderberries. All analytes in juices and sirups gradually decreased during the treatments and long-term storage. On the contrary, the content of quercetin increased with gradual modifications and storage. The highest decrease was observed for vitamin C content. The lowest values in the products from elderberries were reached by quercetin and ascorbic acid.
68

EFEITO DA RUTINA SOBRE A ATIVIDADE DA ADENOSINA DEAMINASE EM RATOS DIABÉTICOS / EFFECT OF RUTIN ON THE ADENOSINE DEAMINASE ACTIVITY IN DIABETIC RATS

Chielle, Eduardo Ottobelli 12 July 2012 (has links)
Diabetes mellitus (DM) is a metabolic disorder of multiple etiology characterized by chronic hyperglycemia resulting from deficiency of insulin production and/or action. This state of hyperglycemia may cause a variety of cardiovascular, renal, neurological and eye complications. Adenosine deaminase (ADA) is an important enzyme responsible for regulation the levels of adenosine (ado) an important component of the system purinergic nucleoside. Changes in ADA activity has been demonstrated in several diseases, including DM. The Rutin (RT) is an abundant polyphenolic flavonoid found in food that exhibits multiple pharmacological activities including antibacterial, antitumoural, vasodilator and hepatoprotective activities. The objective of this study was to investigate the effect of RT on the activity of ADA in serum, tissues and biochemical parameters in models of diabetes induced by streptozotocin (STZ). Diabetes was induced in rats by an intraperitoneal injection of streptozotocin (STZ). RT (100 mg/kg/day) and glibenclamide (10mg/kg/day) were administered for 30 days, except for control groups (non diabetic and diabetic). Six groups of rats were used in the study and grouped based on fasting blood glucose levels after diabetes induction. The results showed an increase in ADA activity in serum and liver of diabetic rats, like transaminases (AST, ALT), -glutamyltransferase (-GT) and glucose. The RT at a concentration of 100 mg/kg was able to reduce the ADA activity in serum and liver tissue when compared with the diabetic control. The protective effect of RT was also observed increases the activity of enzymes ALT and -GT. Significant reductions were also observed in total cholesterol and LDL-cholesterol as well as in blood glucose levels in the diabetic group treated with RT. The results suggest that RT can improve hyperglycemia and hyperlipidemia, and restoring damaged liver function, as well as prevents the increase in ADA activity in serum and liver tissue on diabetic rats treated with this flavonoid. / O Diabetes mellitus (DM) é uma disfunção metabólica de múltipla etiologia caracterizado por hiperglicemia crônica resultante da deficiência da produção e/ou ação da insulina. Esse estado de hiperglicemia pode provocar uma série de complicações cardiovasculares, renais, neurológicas e oculares. A Adenosina deaminase (ADA) é uma importante enzima responsável por regular os níveis de adenosina (ado), um importante nucleosídeo componente do sistema purinérgico. Alterações na atividade da ADA têm sido demonstradas em várias doenças, incluindo o DM. A rutina (RT) é um flavonoide polifenólico abundante nos alimentos que exibe múltiplas atividades farmacológicas como atividade antibacteriana, antitumoral, vasodilatadora e hepatoprotetora. O objetivo deste estudo foi verificar o efeito da RT sobre a atividade da ADA sérica e tecidual e parâmetros bioquímicos em modelos de diabetes induzidos por estreptozotocina (STZ). O diabetes foi induzido através de injeção única intraperitoneal (i.p.) de 55 mg/kg de STZ. A RT (100 mg / kg / dia) e a glibenclamida (10mg/kg/dia) foram administradas durante 30 dias, com exceção dos grupos controles (não diabéticos e diabéticos). Seis grupos de ratos foram utilizados no estudo e agrupados com base nos níveis de glicose em jejum após a indução de diabetes. Os resultados demonstraram um aumento na atividade da ADA no soro e no fígado de ratos diabéticos, assim como das transaminases (AST, ALT), -glutamiltransferase (-GT) e glicose. A RT na concentração de 100 mg/kg foi capaz de reduzir a atividade sérica e em tecido hepático da ADA quando comparado com o controle. O efeito protetor da RT também foi observado sobe a atividade das enzimas ALT e -GT. Reduções significativas foram observadas no colesterol total e LDL-colesterol, bem como, na concentração sérica de glicose no grupo diabético tratado com RT. Os resultados sugerem que a RT pode melhorar a hiperglicemia e dislipidemia, restabelecer danos à função hepática, bem como é capaz de prevenir o aumento da atividade da ADA no soro e no fígado de ratos diabéticos tratados com este flavonoide.
69

EFEITOS DA RUTINA SOBRE A ATIVIDADE DA ACETICOLINESTERASE E SOBRE O COMPORTAMENTO EM RATOS EXPOSTOS AO CÁDMIO / EFFECTS OF RUTIN ON THE ACTIVITY OF THE ACETYLCHOLINESTERASE AND ON THE BEHAVIOR OF RATS EXPOSED TO CADMIUM

Fiorenza, Amanda Maino 09 September 2011 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / This study investigated the effect of administration of cadmium (Cd), Rutin (Rut), or both, on lipid peroxidation in different brain structures, memory, anxiety and activity of the enzyme acetylcholinesterase (AChE) (ex vivo, in vitro and kinetic). The rats received Cd (2 mg / kg) and Rut (40 and 80 mg / kg) by gavage for 21 administrations on alternate days. To the ex vivo study, the animals were divided into six groups (n = 10): saline/saline, saline/Rut40, saline/Rut80, Cd/saline, Cd/Rut40 and Cd/Rut80. The trials of AChE in vitro were performed at concentrations of 1, 5, 10, 25 and 50 mM of Rut in rat brain homogenate controls. The same concentrations were used for kinetic analysis of Electroforus electricus (E.e.AChE). Cd increased lipid peroxidation in all structures analyzed except in the striatum. Rut reversed this effect only in the hypothalamus and hippocampus. Cd caused a decrease in test step-down latency and administration of Rut (40 and 80 mg/kg) reversed this effect of Cd. Cd increased the number and the percent of entries in enclosed arms of plus-maze, suggesting an anxiogenic effect of Cd. Rut (40 and 80 mg/kg) reversed the anxiogenic effect of Cd. Rats that were exposed to Cd and/or treated with Rut showed no altered sensitivity to shock, nor the locomotor activity. The ex vivo activity of the enzyme AChE increased in the cortex and hypothalamus of rats that received only Cd. Rut reversed this increase in both doses. In vitro activity of the enzyme AChE was inhibited at all concentrations of synaptosome cortex, cerebellum, striatum, hippocampus and hypothalamus. The kinetic analysis of the interaction between the Rut and E.e.AChE showed a competitive inhibition. The findings show that treatment with Rut decreased oxidative damage to the membrane, prevented the increase in AChE activity, reversed the memory deficit and anxiety caused by Cd. Moreover, characterized Rut as an inhibitor of AChE, showing that this flavonoid may modulate cholinergic neurotransmission and, consequently, improve cognition. / O presente estudo investigou o efeito da administração de Cádmio (Cd), de Rutina (Rut) ou de ambos, na peroxidação lipídica em diferentes estruturas encefálicas, na memória e ansiedade e na atividade da acetilcolinesterase (AChE) (ex vivo, in vitro e cinética) em ratos. Os animais receberam Cd (2 mg / kg) e Rut (40 e 80 mg / kg) por gavagem diariamente por 21 administrações em dias alternados. Os ratos do estudo ex vivo, foram divididos em seis grupos (n = 10): salina/salina, salina/Rut40, salina/Rut80, Cd/salina, Cd/Rut40 e Cd/Rut 80. Os ensaios da AChE in vitro foram realizados nas concentrações de 1, 5, 10, 25 e 50 μM de Rut em homogeneizado de encéfalo de ratos controles. As mesmas concentrações foram utilizadas para a análise cinética de Electroforus electricus (E.e. AChE). O metal aumentou a peroxidação lipídica em todas as estruturas analisadas exceto no estriado. A Rut reverteu esse efeito somente no hipotálamo e hipocampo. Houve uma piora da memória no grupo que recebeu somente Cd, porém a Rut reverteu essa diminuição de memória tanto nas doses de 40 quanto na de 80 mg/kg. O Cd teve efeito ansiogênico e a Rut reverteu esse comportamento em ambas as doses. A sensibilidade ao choque e a atividade locomotora não foram alteradas nos ratos que foram expostos ao Cd e/ou tratados com Rut. A atividade ex vivo da enzima AChE aumentou no córtex e no hipotálamo dos ratos que receberam somente cádmio. A Rut reverteu esse aumento em ambas as doses. A atividade in vitro da enzima AChE foi inibida em todas as concentrações em sinaptossoma de córtex, no cerebelo, no estriado, no hipocampo e hipotálamo. A análise cinética da interação entre Rut e E.e.AChE caracterizou uma inibição competitiva. Os achados do presente estudo demonstram que o tratamento com Rut diminuiu os danos oxidativos à membrana, impediu o aumento da atividade da AChE, reverteu o déficit de memória e a ansiedade causados pelo Cd. Além disso, caracterizou o composto como um inibidor da AChE , demonstrando que este flavonóide pode modular a neurotransmissão colinérgica e, conseqüentemente, melhorar a cognição.
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Proposta de duas novas terapêuticas, extrato aquoso de Chrysobalanus icaco e rutina, em modelos experimentais de obesidade e resistência à insulina / Proposal of two new therapies, aqueous extract of Chrysobalanus icaco and rutin, on experimental models of obesity and insulin resistance

White, Pollyanna Alves Secundo 13 August 2015 (has links)
Adiposity is a severe risk factor and it´s directly related to the development of several chronic diseases, especially obesity and type 2 diabetes. Numerous trials have been conducted to find and develop new anti-obesity drugs through herbal sources to minimize adverse reactions associated with the present drugs used for obesity and type 2 diabetes treatment. Researches conducted with the aqueous extract of Chrysobalanus icaco L (AECI) have demonstrated decrease in blood glucose levels and prevention of weight gain and fat accumulation in mice liver. The aim of this thesis was to develop new study basis for the development of new therapies and investigate the role of AECI and rutin in the treatment of obesity and type 2 diabetes. The first chapter addresses the action of AECI on the adipose and glycemic profile of obese mice high-fat diet induced. To this end, a group of 34 male C57BL/6J mice were randomly assigned to standard chow or high-fat diet and and further treated with the AECI in two concentrations, 0,35 mg/mL e 0,7 mg/mL. Food intake, feed efficiency, metabolic efficiency, body weight, fat pads weight, serum lipid, fecal lipid excretion, locomotor activity and insulin and glucose sensitivity were evaluated at the end of the 14 weeks of experiment. Results showed that the AECI in the lower concentration increased locomotor activity (p<0.01) and lean mass (p<0.05), decreased fat mass gain (p<0.01), TG levels (p<0.05), and fecal lipid excretion (p<0.01), and normalized insulin (p<0.05) and glucose sensitivity (p<0.05). On the other hand, the AECI in the higher concentration increased food intake (p <0.0001 vs. SC SCA p <0.0001 vs. HFA2 HFD) and the feed efficiency (p <0.05 vs. SC SCA p <0.05 vs. HFA2 HFD), hindering the loss of the body fat and glucose homeostasis. These findings indicates that AECI in lower doses can prevent fat storage or enhance fat utilization, in part, due to the increase of locomotor activity, favoring the glucose homeostasis through the normalization of insulin sensitivity and glucose tolerance. These effects may be related to the antioxidant activity and polyphenol content of the extract. The second chapter addresses the development of a model of insulin resistance TNF-α induced in neuron cells. In this study N2a were treated for 30 minutes with TNF-α, rutin or vehicle and then stimulated with insulin for 15 minutes. The protein lysate was extracted and total and p-Akt were measured, as well as total IkBα through Western blot. Results showed degradation of total IkBα protein in 64.2% (p<0.05) and significant decrease on p-Akt of 36.1% (p<0.001). The rutin, on the other hand, wasn´t able to prevent NF-κB activation, however, it tended to minimize the attenuation of Akt phosphorylation induced by the TNF- α. These findings indicates that TNF-α generated a N2a model of inflammation induced insulin resistance. Furthermore, rutin can contribute with the Akt activation reducing TNF- α damage in these cells. / A adiposidade é um grave fator de risco e está relacionada diretamente ao desenvolvimento de diversas doenças crônicas, em especial a obesidade e o diabetes tipo 2. Diversas pesquisas têm sido conduzidas a fim de desenvolver novas drogas anti-obesidade por meio de fontes à base de plantas, favorecendo a minimização de reações adversas normalmente associadas às drogas mais comumente utilizadas. Estudos prévios com o extrato aquoso da Chrysobalanus icaco (AECI) demonstraram redução dos níveis de glicemia e prevenção do ganho de peso e acúmulo de gordura no fígado de camundongos. O objetivo dessa tese foi de desenvolver meios de estudo para o desenvolvimento de novas terapêuticas e investigar o papel do AECI e da rutina nos respectivos modelos de obesidade e resistência à insulina. O primeiro capítulo trata da ação do AECI no perfil adiposo e glicêmico de camundongos obesos induzidos por dieta hiperlipídica. Para isso, 34 camundongos C57BL/6J machos foram aleatoriamente designados à dieta padrão ou à dieta hiperlipídica e posteriormente tratados com o AECI em duas concentrações, 0,35 mg/mL e 0,7 mg/mL. Consumo, eficiência energética, eficiência metabólica, peso corpóreo, peso dos coxins adiposos, lipídios séricos, excreção fecal lipídica, atividade locomotora, sensibilidade à insulina e tolerância à glicose foram avaliados ao final do experimento. Os resultados mostraram que o AECI em sua menor concentração promoveu o aumento da atividade locomotora (p<0,01) e massa muscular (p<0,05), redução da massa adiposa (p<0,01), dos níveis de triglicérides sanguíneos (p<0.05) e excreção fecal de lipídios (p<0.01), e, normalizou a sensibilidade dos tecidos à ação da insulina (p<0.05) e tolerância à glicose (p<0.05). Por outro lado, o AECI em sua maior concentração promoveu aumento do consumo (p<0.0001 SCA vs SC e p<0.0001 HFA2 vs. HFD) e da eficiência energética (p<0.05 SCA vs SC e p<0.05 HFA2 vs. HFD), não favorecendo, dessa forma, à perda de gordura corporal e homeostase glicêmica. Esses achados indicam que o AECI, em concentrações menores, pode prevenir o armazenamento de gordura ou favorecer o gasto energético, em parte, por meio do aumento da atividade locomotora, promovendo também normalização da sensibilidade à ação da insulina e tolerância à glicose. Esses efeitos podem estar ligados à atividade antioxidante do extrato e seu conteúdo polifenólico. O segundo capítulo trata do desenvolvimento de um modelo de células neuronais resistentes à ação da insulina TNF-α induzida e investigação da ação da rutina sobre esse modelo. Neste trabalho células N2a foram tratadas com TNF-α, rutina ou veículo por 30 minutos e em seguida estimuladas com insulina ou veículo por 15 minutos. Foi extraído o lisato de proteínas e quantificada a Akt fosforilada e total, assim como a IkBα total por meio de Western blot. Os resultados mostraram degradação da proteína IkBα em 64.2% (p<0.05) e redução significativa da fosforilação da Akt em 36.1% (p<0.001) após estimulação com TNF-α. A rutina, por sua vez, não foi capaz de prevenir a ativação da via NF-κB, entretanto tendeu a minimizar a atenuação da fosforilação da Akt induzida pelo TNF-α. Esses dados indicam que o TNF-α gerou um modelo de resistência insulínica mediada por inflamação em células N2a. Ademais, a rutina pode contribuir com a ativação da via Akt na minimização dos dados causados pelo TNF-α.

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