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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

Ensaio clínico randomizado duplo cego com resveratrol no tratamento da dor por endometriose

Silva, Daniel Mendes da January 2017 (has links)
Resveratrol, um fitoestrógeno natural tem sido visto como um opção potencial de tratamento para mulheres com endometriose, porém nenhum estudo clínico adequado foi realizado. Objetivo: Em comparação com placebo, o resveratrol (40mg/dia) reduz níveis de dor após 42 dias de uso em mulheres com endometriose usando pílula anticoncepcional monofásica (PAM). Delineamento do estudo: Neste estudo clínico randomizado, duplo-cego, controlado com placebo clínico, as mulheres com endometriose foram randomizados para receber PAM por 42 dias, para ser tomado com 42 cápsulas idênticas contendo 40 mg de resveratrol ou placebo em frascos codificados Os escores médios de dor foram medidos utilizando uma escala visual analógica (EVA) nos dias 0, 7, 21 e 42. Resultados: Este estudo decorreu entre Junho e Setembro de 2015 envolvendo 44 pacientes. Um software foi utilizado para a geração da sequência da randomização. Foram utilizados envelopes opacos selados e codificados para o cegamento. O tamanho da amostra foi calculada para ter uma chance de 95% de detectar, como significativa ao nível de 1%, uma redução de 90% em comparação com placebo e resveratrol em uma escala de 0 a 10 dor. Uma redução significativa nos níveis de dor foi encontrada entre o dia 0 e o dia 42, no grupo placebo (P = 0.02- de Equações estimação generalizada - GEE) e no grupo de resveratrol (P = 0,003 -GEE). (95% IC) Os escores médios de dor no dia 0 foram de 5,4 (4,2-6,6) no placebo e 5,7 (4,8-6,6) no grupo de resveratrol. Após 42 dias de tratamento, os valores de dor mediana foram [3,5 (2,2-4,9); n = 22] e [2,9 (1,8 a 4); n = 22] em relação ao placebo e resveratrol, respectivamente (p = 0,8 - GEE); diferença média entre os grupos (95% CI) foi de 0,75 (-1,6 a 2,3). Conclusão: Em mulheres com endometriose fazendo uso de pílula anticoncepcional monofásica, os escores de dor após 42 dias de utilização diária de 40 mg de resveratrol não foram significativamente diferentes do placebo. / Background: Resveratrol, a natural phytoestrogen, has been suggested as a possible treatment option for women with endometriosis, but there are no proper randomized clinical trial. Objective : Compared to placebo, does resveratrol (40 mg/day) reduce pain scores after 42 days of use in women with endometriosis using monophasic contraceptive pill (COC). Study Design: In this randomized double-blinded, placebo controlled clinical trial, women with endometriosis were randomized to receive COC for 42 days, to be taken with 42 identical capsules containing 40 mg of resveratrol or placebo in coded bottles. Median pain scores measured with an analog visual scale (AVS) on day 42 was the primary outcome. Results: This trial took place between June and September 2015 and enrolled 44 subjects. A software generated the randomization sequence. Allocation sequence was concealed in coded sequenced opaque sealed envelopes. Sample size was calculated to have a 95% chance of detecting, as significant at the 1% level, a 90% reduction comparing placebo and resveratrol in a 0 to 10 pain scale. A significant reduction in pain levels was found between day 0 and day 42, in placebo ( P =0.02- Generalized Estimating Equations - GEE) and in the resveratrol group ( P =0.003 -GEE). Mean (95%CI) pain scores at day 0 were 5.4 (4.2 to 6.6) in placebo and 5.7(4.8 to 6.6) in resveratrol groups. After 42 days of treatment, median pain values were [3.5 (2.2 to 4.9); n=22] and [2.9 (1.8 to 4); n=22] in the placebo and in the resveratrol groups, respectively ( P =0.8 - GEE); median difference between groups (95%CI) was 0.75 ( -1.6 to 2.3). Conclusion : In women with endometriosis in use of monophasic contraceptive pill, pain scores after 42 days of daily use of 40 mg of resveratrol are not significantly different from placebo.
62

Vasculoprotective Effects of Insulin and Resveratrol In Vivo

Breen, Danna 23 February 2011 (has links)
Atherosclerosis is a leading cause of morbidity and mortality worldwide and type 2 diabetes and obesity-associated metabolic syndrome, both characterized by insulin resistance, are potent risk factors. These conditions also increase the risk for restenosis after revascularization procedures used for treatment of atherosclerosis. Studies have shown that insulin and resveratrol (RSV), a red wine polyphenol, decrease neointimal growth after vessel injury in models of restenosis, demonstrating a protective effect on the vasculature. However, oral glucose and sucrose were used in insulin studies to maintain normoglycemia, and their effect on neointimal formation was not assessed. Several studies have shown that nitric oxide (NO) production is stimulated by insulin and RSV, and since NO can decrease neointimal growth, the objective of this thesis was to address the mechanism of action of insulin or RSV to protect against restenosis, and determine whether NO production mediates these effects. To examine this, we treated rats with insulin or RSV and performed arterial balloon injury. In Study 1, insulin reduced neointimal area after injury in rats receiving oral glucose but not oral sucrose. Oral glucose alone had no effect on neointimal formation or insulin sensitivity whereas oral sucrose increased neointimal growth and induced insulin resistance. In Study 2, insulin decreased neointimal area and cell migration, and increased re-endothelialization. These effects were abolished by nitric oxide synthase (NOS) inhibition. In addition, insulin increased eNOS protein expression in the vessel. In Study 3, RSV reduced neointimal growth, cell proliferation, and migration after injury, without affecting re-endothelialization. Most of these effects were abolished by NOS inhibition, except for the decrease in cell migration. Insulin sensitivity and systolic blood pressure were not affected by RSV. Together, the results demonstrate that insulin, independent of glycemic effects, and RSV have a protective effect on the vessel against restenosis, which is mediated by NO. Since both insulin and RSV decrease neointimal formation without negatively impacting re-endothelialization, insulin or RSV treatment could provide some advantage over anti-mitogenic agents currently used in drug-eluting stents, which delay re-endothelialization. These studies suggest that insulin or RSV may have clinical potential in the prevention of restenosis after angioplasty.
63

Vasculoprotective Effects of Insulin and Resveratrol In Vivo

Breen, Danna 23 February 2011 (has links)
Atherosclerosis is a leading cause of morbidity and mortality worldwide and type 2 diabetes and obesity-associated metabolic syndrome, both characterized by insulin resistance, are potent risk factors. These conditions also increase the risk for restenosis after revascularization procedures used for treatment of atherosclerosis. Studies have shown that insulin and resveratrol (RSV), a red wine polyphenol, decrease neointimal growth after vessel injury in models of restenosis, demonstrating a protective effect on the vasculature. However, oral glucose and sucrose were used in insulin studies to maintain normoglycemia, and their effect on neointimal formation was not assessed. Several studies have shown that nitric oxide (NO) production is stimulated by insulin and RSV, and since NO can decrease neointimal growth, the objective of this thesis was to address the mechanism of action of insulin or RSV to protect against restenosis, and determine whether NO production mediates these effects. To examine this, we treated rats with insulin or RSV and performed arterial balloon injury. In Study 1, insulin reduced neointimal area after injury in rats receiving oral glucose but not oral sucrose. Oral glucose alone had no effect on neointimal formation or insulin sensitivity whereas oral sucrose increased neointimal growth and induced insulin resistance. In Study 2, insulin decreased neointimal area and cell migration, and increased re-endothelialization. These effects were abolished by nitric oxide synthase (NOS) inhibition. In addition, insulin increased eNOS protein expression in the vessel. In Study 3, RSV reduced neointimal growth, cell proliferation, and migration after injury, without affecting re-endothelialization. Most of these effects were abolished by NOS inhibition, except for the decrease in cell migration. Insulin sensitivity and systolic blood pressure were not affected by RSV. Together, the results demonstrate that insulin, independent of glycemic effects, and RSV have a protective effect on the vessel against restenosis, which is mediated by NO. Since both insulin and RSV decrease neointimal formation without negatively impacting re-endothelialization, insulin or RSV treatment could provide some advantage over anti-mitogenic agents currently used in drug-eluting stents, which delay re-endothelialization. These studies suggest that insulin or RSV may have clinical potential in the prevention of restenosis after angioplasty.
64

Mechanisms of aryl hydrocarbon receptor and estrogen receptor action in breast cancer cells

Lee, Jeong Eun 12 April 2006 (has links)
In MCF7 and T47D cells cotreated with 1 nM 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) plus 0.1-10 μM 3’,4’-dimethoxy flavone (DMF), there was a concentration-dependent decrease in the TCDD-induced ethoxyresorufin O-deethylase (EROD) activity. Gel mobility shift assays showed that 3’,4’-DMF inhibited TCDD-induced aryl hydrocarbon receptor (AhR) transformation in rat liver cytosol and blocked TCDD-induced formation of the nuclear AhR complex in MCF7 and T47D cells. The antiestrogenic activity of TCDD in estrogen-induced transactivation assays in MCF7 cells was reversed by 3’,4’-DMF, confirming the AhR antagonist activity of this compound in breast cancer cells. Cotreatment of T47D and MCF7 cells with TCDD and 10 μM resveratrol inhibited induction of CYP1A1 mRNA and EROD activity. Resveratrol did not inhibit TCDD-induced AhR transformation and reporter gene activity. Actinomycin D chase experiments in T47D cells showed that the mechanism of inhibition of CYP1A1 mRNA and EROD activity is due to an increased rate of CYP1A1 mRNA degradation, suggesting that resveratrol inhibits CYP1A1 via an AhR-independent post-transcriptional pathway. Vitamin D receptor-interacting protein 150 (DRIP150) coactivated estrogen receptor α (ER α)-mediated transactivation and the response was AF2-dependent in ZR75 breast cancer cells. C-and N-terminal NR-boxes (amino acids 1186-1182 and 73-69, respectively) were not necessary for coactivation of ERα. Analysis of DRIP150 deletion mutants identified a 23 amino acid sequence (811-789) required for coactivation. The 23 amino acid contained two regions at amino acids 789-794 and 795-804 which resembled α-helical motifs identified in Lanuguinosa lipase/histamine N-methyl transferase and hepatocyte nuclear factor 1, respectively. A squelching assay using specific point mutations within each α-helix showed that the NIFSEVRVYN (795-804) region was the critical sequence required for the coactivator activity of DRIP150.
65

An investigation into the anti-tumour properties and underlying mechanisms of natural polyphenols against ovarian cancer.

Tino, Alexandria January 2014 (has links)
Ovarian cancer is the deadliest gynaecologic cancer in New Zealand. Its high mortality rate is due to the fact that it is usually diagnosed at an advanced stage. Advanced ovarian cancer is less responsive to current cytotoxic treatment. Thus, there is an urgent need for novel anti-cancer drugs that can improve patient longevity and quality of life. One of the clinical features of advanced ovarian cancer is the growth of secondary tumours due to the highly metastatic nature of the disease. Cancer cells disseminate from the ovary, some form cell clusters that travel through the abdominal cavity by physiological movement of body fluid and then deposit on the abdominal wall and internal organs to generate secondary tumours. The exact mechanisms of how these cells metastasize are unclear, but prognosis typically worsens if levels of vascular endothelial growth factor (VEGF) are elevated. This study investigated the anti-tumour activities of naturally occurring food compounds resveratrol, acetyl resveratrol and (-)-Epicatechin-3-gallate (EGCG), in cell spheroids/clusters of ovarian cancer. It also examined the protein expression of various proteins involved in the NF-κB signalling pathway. This pathway has been suggested to mediate the secretion of VEGF and is a possible target for the naturally occurring compounds. Results show that resveratrol and acetyl resveratrol reduce cell growth and cellular metabolism in a dose-, time- and cell line- dependent fashion. In addition, the reduction of VEGF is also dose-, time- and cell line- dependent. Paradoxically, another angiogenic protein interleukin-8 (IL-8) secretion is increased. Resveratrol and acetyl resveratrol attenuate the expression of NF-κB but this effect is cell line specific. EGCG has limited effect on cell growth, cellular metabolism and the secretion of VEGF and IL-8. These findings suggest that resveratrol and its derivative may have the ability to supress the angiogenic activity of ovarian cancer cells and warrant further in vivo study.
66

Regulation of Vascular Endothelial Growth Factor in endometrial cancer cells by food compounds

Dann, James MacBeth January 2008 (has links)
Endometrial cancer is one of the most significant gynaecological malignancies that affect women from New Zealand and the rest of the world. One of the critical stages in the development of a tumour is the onset of hypoxia. The malignancy responds by having raised levels of Hypoxia Inducible Factor (HIF) that in turn induces increased production of Vascular Endothelial Growth Factor (VEGF). VEGF is a potent angiogenic factor that will mediate vascular supply of nutrients and oxygen to the developing tumour. The aim of this study was to investigate whether two compounds found in extracts of plant materials, Resveratrol (Resveratrol) and Epigallocatechin gallate (EGCG), altered the levels of VEGF in the supernatant of cultured endometrial cancer cells. Resveratrol is a phytoalexin that is found in many foods, such as grapes, nuts and berries, as well as in high concentrations in some red wines. 100 µM of resveratrol was added to cell cultures for 24 hours. VEGF levels in the supernatant were then analysed using ELISA. Resveratrol was found to have significant inhibitory effects in both primary endometrial cancer cell cultures and immortalised endometrial cancer cell cultures. Resveratrol was also shown to reverse the increase in VEGF caused by the hypoxia mimic cobalt chloride (CoCl₂). Epigallocatechin gallate (EGCG) is an antioxidant catechin extracted from green tea. The effect of EGCG was analysed using the same method as for resveratrol. 100 µM of EGCG was also shown to have a significant inhibitory effect on the level of VEGF in the supernatant of cultured endometrial cancer cells, as well as reducing the effect of CoCl₂. These results suggest that selected food compounds, resveratrol and EGCG, can reduce VEGF levels by inhibiting HIF. Further investigation This may have anti-tumour effects in women with endometrial cancer.
67

Wirkung von Resveratrol auf die Biologie humaner Fettzellen

Kukulus, Vera, January 2008 (has links)
Ulm, Univ., Diss., 2008.
68

A novel resveratrol analog its cell cycle inhibitory, pro-apoptotic and anti-inflammatory activities on human tumor cells /

Lin, Boren. January 2006 (has links)
Thesis (Ph.D.)--Kent State University, 2006. / Title from PDF t.p. (viewed Sept. 14, 2006). Advisor: Chun-Che Tsai. Includes bibliographical references (p. 133-151).
69

Reações de acoplamento C-C : desenvolvimento de sistemas catalíticos, estudo do mecanismo e aplicação na síntese do trans-resveratrol

Nobre, Sabrina Madruga January 2008 (has links)
Esta tese de doutorado trata de reações de acoplamento C-C em termos do desenvolvimento de novos sistemas catalíticos (primeira parte), estudo do mecanismo (segunda parte) e da aplicação dessas reações na síntese de moléculas com atividade biológica (terceira parte). Foram sintetizados e caracterizados dois novos complexos de paládio. O primeiro composto organometálico de paládio sintetizado corresponde ao intermediário da etapa de adição oxidativa do haleto de arila ao paládio zerovalente das reações de acoplamento C-C em geral. O segundo complexo é um iminopaladaciclo catiônico, obtido a partir do ciclopaladato de enxofre. Estes compostos organometálicos se mostraram excelentes precursores para a reação de Suzuki, bem como o sistema Pd(OAc)2/iminofosfina, para o qual foi feito um estudo de otimização detalhado. A segunda parte do trabalho consistiu no estudo da formação da espécie cataliticamente ativa na reação de acoplamento Suzuki para diferentes sistemas catalíticos. Para o ciclopaladato contendo enxofre foi possível mostrar que o Pd(0) pode ser formado pela redução direta do precursor catalítico, ou através das reações de transmetalação-eliminação redutiva na presença de ácido arilborônico. Enquanto que na ausência de fosfina somente parte do paládio é ativa e há formação de nanopartículas (~3 nm), a adição de fosfina levou a sistemas onde todo o paládio fica ativo na solução. Finalmente, foi desenvolvido um protocolo one pot para a síntese seletiva de estilbenos não simétricos utilizando duas reações de Heck em seqüência com o mesmo catalisador. Este protocolo foi aplicado para a síntese de um precursor do resveratrol, com rendimento global de 95% e regioespecífico e estereoseletiva para o trans-estilbeno (trans/cis = 95:5). / In this thesis it was described the results on the Pd-catalyzed C-C coupling reactions. In the first part a new catalytic system based on iminophosphine ligands for the Suzuki reaction was developed. The second part was devoted to the mechanistic aspects of Suzuki reaction and in the third part Heck coupling reaction was applied for the selective synthesis of molecules with biological activity. Two new palladium organometallics containing iminophosphine ligand were synthesized, characterized and evaluated as catalyst for the Suzuki reaction. The first organomettalic corresponds to the intermediate of oxidative addition step in the general catalytic cycle for coupling reactions. The second one is a cationic sulfur-containing paladacycle. These organomettalic compounds gave similar activity compared with the system Pd(OAc)2/iminophosphine, for which we have made a detailed optimization. In the case of the free-phosphine sulfur-containing paladacycle the Pd(0) can be formed by the direct reduction of the catalytic precursor, or by the reductive transmetallation-elimination reactions in the presence of arylboronic acid. In the absence of phosphine, only part of the palladium is active. Pd nanoparticles (~3 nm) were observed and are problaby the only reservoir of active species. On the other hand, a clear homogeneous catalysis took place in the presence of iminophosphine ligand with all palladium dissolved in solution as palladium-phosphine complexes. Finally, starting from ethylene, a one-pot protocol based in two consecutive Heck reactions was developed for the selective synthesis of non symmetrical trans-stilbenes. In this protocol, the ethylene was selectively double-arylated in the presence of the same palladium catalyst, and a precursor of the resveratrol was obtained in high yield (95%) and stereoselectivity (trans:cis = 95:5).
70

Efeito do trans-resveratrol sobre a longevidade e o metabolismo de glicogênio de Drosophila melanogaster em diferentes idades

Fernandes, Felipe Amorim January 2006 (has links)
O trans-resveratrol é uma fitoalexina natural encontrada em uvas, amoras, amendoim e muitas espécies de plantas. Em uvas o trans-resveratrol é responsável pela proteção natural contra doenças e sua concentração depende da origem geográfica, da variedade e dos métodos de fabricação do vinho; sendo considerado por muitos autores como um geroprotetor. O objetivo do presente trabalho foi verificar o efeito do transresveratrol na longevidade e no metabolismo de carboidratos (glicogênio, atividade e expressão da enzima glicogênio fosforilase - GFT) de Drosophila melanogaster em diferentes idades (0, 7, 14, 18 e 21 dias). Para a análise da longevidade espécimes de D. melanogaster com idade de 10 dias foram colocados em vidros contendo meio de cultura padrão acrescido de água ou dimetilsulfóxido (DMSO) 0,03%, ou trans-resveratrol nas concentrações de 1, 10 ou 20μM para ovoposição durante 24 horas, a prole recebeu os seus respectivos tratamentos durante toda a vida. Para as análises do metabolismo de glicogênio os espécimes de D. melanogaster foram colocados em meio de cultura padrão adicionado de água ou dimetilsulfóxido 0,03% (DMSO) ou ainda, trans-resveratrol na concentração de 1μM dissolvido em DMSO (0,03%) para ovoposição; seus ovos foram mantidos até a eclosão, durante a fase adulta os animais continuaram a receber os seus respectivos tratamentos até os pontos em que foram feitas as determinações bioquímicas e moleculares. Os resultados indicam que o tratamento com trans-resveratrol modulou o metabolismo de carboidratos em fêmeas e em machos de forma diferenciada; contudo, este composto não foi capaz de alterar a expressão gênica da GFT. Nas fêmeas tratadas com trans-resveratrol 1μM verificou-se um aumento de 127% na longevidade quando comparado ao grupo controle. Já nos machos tratados com trans-resveratrol 1μM observou-se um acréscimo de 50% na longevidade quando comparado ao grupo controle. Em ambos sexos tratados com Trans-resveratrol 10 e 20μM não houve aumento significativo da longevidade. Com base nos resultados podemos sugerir que o trans-resveratrol como outros antioxidantes descritos na literatura tem seus efeitos benéficos na menor dose administrada, podendo nas doses mais elevadas estar atuando como um pró-oxidante. Os resultados obtidos sugerem que o trans-resveratrol modula o metabolismo do glicogênio tanto em machos como em fêmeas e aumenta a longevidade do modelo experimental testado.

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