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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

Effect of proanthocyanidins and consumption frequency of sterols and fatty acids on lipoprotein metabolism in hamsters. / CUHK electronic theses & dissertations collection

January 2010 (has links)
Grape seed proanthocyanidins (GSP) as a cholesterol-lowering nutraceutical has been investigated in both humans and animals, however, little is known of how it interacts with the genes and proteins involved in lipoprotein metabolism in vivo. So the first objective of the present study was to investigate the effect of GSP supplementation on blood cholesterol level and gene expression of cholesterol-regulating enzymes in Golden Syrian hamsters maintained on a 0.1% cholesterol diet. / Hypercholesterolemia is one of the major proven risk factors for atherosclerosis. Decreasing blood total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) levels with cholesterol-lowering nutraceuticals and dietary intake modification could slow or reverse the progression of cardiovascular disease. / In conclusion, the present study confirmed that hypocholesterolemic activity of GSP was most likely mediated by enhancement of bile acid excretion and up-regulation of CYP7A1. The present study also demonstrated that frequent cholesterol and myristic acid intake is associated with elevation of plasma TC level, while beta-sitosterol intake frequency had no effect on plasma cholesterol for a given amount. / In the beta-sitosterol consumption frequency study, hamsters fed the basal diet with a gavage-administration of 3 mg cholesterol 3 times (control), or a gavage-administration of 3 mg beta-sitosterol with 3 mg cholesterol 3 times per day (high beta-sitosterol intake frequency), or a gavage-administration of 9 mg beta-sitosterol with 3 mg cholesterol for one time and 3 mg cholesterol for the other two times (low beta-sitosterol intake frequency). The results demonstrated that for a given dose of beta-sitosterol, the administration frequency had no or little effect on plasma lipoprotein profiles. The present study also found that cholesterol-lowering activity of beta-sitosterol was mediated by its inhibition on the intestinal cholesterol absorption with up-regulation of NPC1L1, ATP binding cassette transporters G5 and G8 (ABCG5/8) and MTP. / In the cholesterol consumption frequency study, hamsters were given daily 9 mg of cholesterol either in diet (high cholesterol intake frequency) or a gavage-administration of 3 times 3 mg (regular cholesterol intake frequency) and 1 time 9 mg (low cholesterol intake frequency). The results demonstrated that there was an increasing trend in concentrations of plasma TC, Non-HDL-C, TC/HDL-C ratio and TG in association with the cholesterol intake frequency. It is the first time to demonstrate that the increasing cholesterol intake frequency increased the apparent cholesterol absorption. Elevation of plasma TC and cholesterol absorption is most likely mediated by up-regulation of intestinal Niemann-Pick C1-like 1 (NPC1L1), acyl coenzyme A: cholesterol acyltransferase 2 (ACAT2), and microsomal triacylglycerol transport protein (MTP) gene expression. / In the myristic acid consumption frequency study, hamsters were given daily 210 mg of myristic acid either in diet (high myristic acid intake frequency) or a gavage-administration of 3 times 70 mg (regular myristic acid intake frequency) and 1 time 210 mg (low myristic acid intake frequency). The results showed that the increasing consumption frequency elevated plasma TC, Non-HDL-C and HDL-C levels. Elevation of plasma TC and HDL-C is most likely mediated by up-regulation of NPC1L1 and down-regulation of scavenger receptor BI (SR-BI) gene expression via enhancement of dietary myristic acid absorption. / The results affirmed supplementation of 0.5% or 1.0% GSP could decrease plasma TC, non-high density lipoprotein cholesterol (Non-HDL-C) and triglyceride (TG) levels. In addition, dietary GSP was able to increase the excretion of bile acids by 3--4 folds, this was partially mediated by up-regulation of Cholesterol 7 alpha-hydroxylase (CYP7A1) in both transcriptional and translational levels. It was concluded that the hypocholesterolemic activity of GSP was most likely mediated by enhancement of bile acid excretion and up-regulation of CYP7A1. / The second objective of the present study was to investigate the effect of cholesterol, myristic acid and beta-sitosterol consumption frequency on plasma lipoprotein profiles in hamsters. Numerous studies reported that dietary cholesterol and saturated fatty acids elevated plasma TC level, whereas dietary phytosterols in moderate and high doses favorably reduced plasma TC and LDL levels. However, it is still unknown whether consumption frequency of sterols and fatty acids could affect plasma cholesterol level and lipid profiles. / Jiao, Rui. / Adviser: Chen Zhen Yu. / Source: Dissertation Abstracts International, Volume: 73-02, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 123-150). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
62

On the possible use of oxysterols for the diagnosis and evaluation of patients with neurological and neurodegenerative diseases /

Leoni, Valerio, January 2005 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2005. / Härtill 5 uppsatser.
63

Ethyl N-bromo-alkylcarbamates as heterocyclic precursors and extractives from Oceanapia sp.

Dovey, Martin Charles. January 2001 (has links)
The synthesis of p-lactams has been of foremost importance since the discovery of penicillin by Sir Alexander Fleming, in 1928, and its susequent structure elucidation in 1945. Ethyl N-2-bromo-alkylcarbamates show considerable potential as precursors to p- lactams. In the past, p-lactams have been prepared by many methods, none of which have involved 2-3 bond formation. The proposed ring closure using ethyl N-2-bromoalkylcarbamate involves 2-3 bond formation, making this method of synthesis novel. This work describes two attempted methods of cyclisation. The first using a Grignard reagent, and the second, using abstraction of an acidic proton a to a phosphonate group. These methods of intramolecular cyclisation were based on analogous intermolecular additions, which are also described. The second method was also used to determine the general potential of ethyl N-bromo- alkylcarbamtes as precursors to other heterocyclic systems. / Thesis (M.Sc.)-University of Natal, Durban, 2001. / NRF & NRF/DEA & T.
64

Method development for the application of vibrational spectroscopy to complex organic-inorganic materials in astrobiology : a systematic development of Raman spectroscopy and related analytical methods to the structural chemistry at organic (biological) and inorganic (mineralogical) interfaces of material assemblies relevant to astrobiology and inter-planetary science

Whitaker, Darren Andrew January 2013 (has links)
In the search for the conformation of extant or extinct life in an extraterrestrial setting the detection of organic molecular species which may be considered diagnostic of life is a key objective. These molecular targets comprise a range of distinct chemical species, with recognisable spectroscopic features. This project aims to use these features to develop an in-situ molecular specific Raman spectroscopic methodology which can provide structural information about the organic–inorganic interface. The development of this methodology identified a surface enhanced Raman spectroscopic technique, that required minimal sample preparation, allowed for the detection of selected organic species immobilised on an inorganic matrix and was effective for quantities below those which conventional dispersive Raman spectroscopy would detect. For the first time spectral information was gained which allowed analysis of the organic–inorganic interface to be carried out, this gave an insight into the orientation with which molecules arrange on the surfaces of the matrices. Additionally a method for the detection of organic residues intercalated into the interlamellar space of smectite type clays was developed. An evaluation of the effectiveness of uni and multivariate methods for the analysis of large datasets containing a small number of organic features was also carried out, with a view to develop an unsupervised methodology capable of performing with minimal user interaction. It has been shown that a novel use of the Hotellings T2 test when applied to the principal component analysis of the datasets combined with SERS allows identification of a small number of organic features in an otherwise inorganic dominated dataset. Both the SERS and PCA methods hold relevance for the detection of organic residues within interplanetary exploration but may also be applied to terrestrial environmental chemistry.
65

Caracterização geoquímica orgânica em sedimentos presentes nos Pockmarks e Diápiros do talude sul do Brasil / Organic geochemical characterization in sediments present in the Pockmarks and Diapirs of the southern slope of Brazil

Nagaoka, Doris 18 May 2018 (has links)
Os marcadores orgânicos moleculares (hidrocarbonetos alifáticos, esteróis e álcoois) em amostras de sedimentos superficiais e de testemunhos curtos coletados em diápiros e pockmarks localizados no talude sul do Brasil, foram utilizados para identificar as possíveis contribuições biogênicas (autóctones / alóctones). De modo geral, tanto nas amostras superficiais como ao longo dos testemunhos, o maior acúmulo de carbono orgânico total nos pockmarks foi observado, indicando o possível aprisionamento de sedimentos e de matéria orgânica no interior das concavidades. A presença de β-sitosterol, campesterol, álcoois e n-alcanos pesados, indicaram contribuições terrígenas para a área de estudo, que pode ser advinda da descarga continental do Rio da Prata, uma vez que a predominância terrígena é proveniente das pradarias, típica vegetação do Uruguai e do sul do Rio Grande do Sul. O transporte de sedimentos terrígenos ocorre em direção ao norte, ao longo da plataforma continental sul brasileira, pela Corrente Costeira do Brasil. A presença de detritos de fitoplâncton e zooplâncton também ocorre devido à influência dos nutrientes do Rio da Prata. As possíveis liberações de gás/fluido, que sustentaram ecossistemas quimiossintéticos em diferentes intervalos de dois testemunhos em pockmark e diápiro foram constatadas através da presença relativamente maior de n-alcanos leves com número par de carbonos. / Organic molecular markers (aliphatic hydrocarbons, sterols and alcohols) in superficial and short cores sediment samples collected in diapirs and pockmarks located in the southern slope of Brazil were used in order to identify the possible biogenic contributions (autochthonous / allochthonous). In general, in surface samples and throughout the cores samples, the greatest accumulation of total organic carbon in the pockmarks was observed, indicating the possible entrapment of sediments and organic matter inside the concavities. The presence of β-sitosterol, campesterol, alcohols and heavy n-alkanes indicated terrigenous contributions to the study area, which may be due to the continental discharge of Río de la Plata, since the terrigenous predominance is due to the prairies, a typical vegetation of Uruguay and the south of Rio Grande do Sul. The terrigenous sediments transport is carried through the North, along the Brazilian continental shelf, by the Coastal Stream of Brazil. The presence of phytoplankton and zooplankton debris is also due to the influence of the nutrients contribution from Río de la Plata. Possible gas / fluid releases, which sustained chemosynthetic ecosystems at different intervals of two pockmark and diaper cores, were verified by the relative predominance of even-numbered carbon n-alkanes.
66

"Avaliação de introdução de esteróis fecais e hidrocarbonetos marcadores geoquímicos em sedimentos da Baía do Almirantado, Península Antártica" / Evaluation of fecal sterols and geochemical markers hydrocarbons in sediments from Admiralty Bay, Antartica.

Martins, César de Castro 01 February 2002 (has links)
Esgoto e hidrocarbonetos provenientes de atividades humanas são as principais fontes de poluição para o meio ambiente marinho antártico. Esteróis e hidrocarbonetos como n-alcanos, policíclicos aromáticos (PAHs) e alquilbenzenos lineares (LABs) foram investigados em sedimentos superficiais coletados na Baía do Almirantado, Antártica durante o verão de 1997/1998 e 1999/2000. Estes compostos são citados como traçadores de dejetos humanos e introdução de óleos ao longo de áreas costeiras de todo o mundo. As técnicas analíticas utilizadas foram a cromatografia a gás com detector de ionização de chama (GC-FID) e espectrômetro de massa (GC-MS). Análises de esteróis indicaram que o esgoto atinge até 700 metros desde a saída de efluentes, mas somente o ponto de descarga pode ser considerado poluído. Dados de LABs concordaram com os resultados obtidos para os esteróis indicando que dejetos humanos chegam até 1 Km desde a estação brasileira e que esteróis encontrados em pontos distantes são provenientes de fontes naturais. Os níveis obtidos para n-alcanos e PAHs foram similares àqueles obtidos em outros estudos envolvendo regiões antárticas. Contribuições biogênicas e pequenas introduções antropogênicas são as fontes dos n-alcanos detectados. PAHs encontrados em pontos distantes são associados como pequena contribuição de óleos enquanto que amostras coletadas na saída de esgoto e até 50 metros apresentam PAHs de origem pirolítica ou de esgotos. Este estudo concluiu que apenas a saída de efluentes pode ser considerada ponto altamente poluído e verificou a presença de uma substancial diminuição do aporte de esgoto com o aumento da distância desde a fonte. / Sewage and oil contribution are the main sources of pollution from the scientific stations to the antarctic marine environment. Sterols and hydrocarbons such as n-alkanes, polyciclic aromatics (PAHs) and linear alkylbenzenes (LABs) were investigated on surface sediments from Admiralty Bay, King George Island, Antarctica, collected during austral summer of 1997/1998 and 1999/2000 It has been previously used as a tracer from human waste and oil inputs along the coastal areas around the world. The analytical techniques used were gas chromatography with flame ionization detection (GC-FID) or attached with a mass spectrometer (GC-MS). Analyses of sterols showed that sewage moves until 700 meters since sewer outfall, but only the discharge point can be considered polluted. Data from LABs agreed with sterols results indicating that human wastes arrive until 1 Km from brazilian station and sterols found in remote areas were from natural contributions. N-alkanes and PAHs showed the same levels than previous studies from pristine areas in antarctic continent. Biogenic and little antropogenic sources are the origins from n-alkanes. PAHs found in distant points are associated with small oil contribution while samples collected in sewer outfall and until 50 meters far presented PAHs from combustion process and sewage. This study concluded that only the sewage discharge point is very polluted however there is a substantial sewage input decrease with the increase of distance from outfall.
67

O óleo de abacate (Persea americana Mill) como matéria-prima para a indústria alimentícia / The avocado oil (Persea americana Mill) as raw material for food industry

Danieli, Flávia 01 September 2006 (has links)
Hábitos de vida saudáveis e uma dieta balanceada aliados ao alto consumo de frutas e vegetais, estão associados a redução do risco de doenças e à manutenção da saúde. O óleo de abacate possui em sua composição substâncias bioativas capazes de prevenir e controlar as dislipidemias. Como existem poucas pesquisas científicas avaliando o potencial deste óleo para consumo humano, o presente trabalho estudou os processos de extração e refino do óleo de abacate, bem como suas propriedades funcionais. Os resultados mostraram que os processos de extração e refino do óleo a partir da variedade Margarida são tecnicamente viáveis, o que o torna excelente matéria-prima para a indústria alimentícia. Além disso, possui um perfil de ácidos graxos muito semelhantes ao azeite de oliva, predominando em ambos o ácido oléico, que em conjunto com os esteróis vegetais e a vitamina E presentes, é capaz de influenciar positivamente o controle metabólico do colesterol, prevenindo ou retardando as doenças cardiovasculares. / Healthy life habits and an equilibrate diet, associated with a high fruit and vegetable intake, are joined with the prevention of diseases and health maintenance. The avocado oil has in these composition bioactives substances that can help in the prevention and control of hyperlipidemia. As there are a few scientific researches evaluating the oil potential for human consumption, the present proposal studied the extraction and refining process of avocado oil and its functional properties. The results have been showed that extraction and refining process of Margarida's variety are technically possible, became it an excellent raw material for food industry. Besides, the fatty acid composition of avocado oil are similar to olive oil, predominating in both, the oleic acid, that together of sterols and vitamin E presents, can to influence to metabolic control of cholesterol, preventing or delaying the cardiovascular disease.
68

"Metodologia para determinação de biomarcadores geoquímicos orgânicos em sedimentos - Hidrocarbonetos Alifáticos e Aromáticos, Esteróis e Alquenonas" / "Methodology for determination of organic geochemistry biomarkers in sediment - Aliphatic hydrocarbons, PAHs, Sterols and Alkenones"

Lourenço, Rafael André 18 June 2003 (has links)
O destino de grande parte da matéria orgânica presente nos oceanos é o sedimento marinho. Essa matéria orgânica, que vai sendo armazenada ao longo dos anos, produz uma reserva única de informações sobre os processos biogeoquímicos ocorridos no passado e como esses processos responderam às mudanças ambientais. Certas moléculas orgânicas são sintetizadas apenas por organismos marinhos ou somente por plantas superiores terrestres. A abundância relativa desses compostos em sedimentos marinhos pode ser usada para determinar a contribuição de matéria orgânica terrestre ou marinha que foi depositada. Outros compostos, cujas fontes naturais são raras ou inexistem, encontrados em sedimentos, refletem a influência antrópica no meio. Há ainda compostos, com origem biológica especifica, cujas estruturas são influenciadas pelo controle enzimático dos organismos que os produzem, que são influenciados pelo meio. Esses compostos, cuja presença pode fornecer evidências inequívocas da sua fonte ou informações sobre condições oceanográficas recebem o nome de marcadores biológicos e são comumentemente abreviados como biomarcadores. Esse trabalho produziu uma metodologia analítica para identificação e quantificação de biomarcadores como os hidrocarbonetos alifáticos, hidrocarbonetos policíclicos aromáticos, esteróis e alquenonas através de uma única extração lipídica. Essa metodologia foi avaliada por diversos critérios analíticos e validada através de materiais de referência e de exercícios de comparação entre laboratórios. A metodologia foi aplicada em um testemunho de sedimento marinho obtido em Cabo Frio. A quantificação das alquenonas nas amostras do testemunho permitiu estimar a variação da temperatura da superfície oceânica ao longo dos anos e correlacioná-la com variações na intensidade da ressurgência, além de permitir verificar como os demais biomarcadores variaram em função da variação da temperatura do meio onde foram sintetizados. / The fate of most organic matter in the oceans is the marine sediment. This preserved organic matter became an unique reservoir of information about the operation of biogeochemical processes in the geological past, and how these processes responded to environmental changes. Some molecules are only synthesized by sea organisms, others only by higher plants. The relative abundance among these compounds in sea sediments can be used to determine the source of the organic matter. Other organic compounds, without natural sources, are an indicative of anthropogenic influence. The marine sediment also can accumulate compounds with the specific biological sources, which structures are influenced by the enzymatic control of the precursor organisms. All of these compounds, which can provide clear evidences of its sources or information about oceanographic conditions, are called biological markers or biomarkers. The present work put out an analytic method to identify and quantify biomarkers like aliphatic hydrocarbons, PAHs, sterols and alkenones with only one lipidic extraction. This method was evaluated by several analytic criteria and validated by reference material and by interlaboratory comparison study. The method was used to analyze a marine sediment core from Cabo Frio. The alkenones quantification in this core allowed not only appreciate changes in the sea surface temperature (SST) along the years and correlate them with changes in the upwelling, but also verify how the other biomarkers responded to SST changes.
69

Effects of phytosterols and phytosterol oxidation products on the vasculature.

January 2011 (has links)
Yang, Chao. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 137-146). / Abstracts in English and Chinese. / Thesis Committee --- p.i / Acknowledgements --- p.ii / Contents --- p.iii / Declaration --- p.vii / Abstract --- p.viii / 摘要 --- p.xi / Abbreviations --- p.xiii / Chapter CHAPTER ONE: --- INTRODUCTION / Chapter 1.1 --- Occurrence and Structure of Phytosterols in Plants --- p.P.1 / Chapter 1.2 --- Biological Effects of Phytosterols / Chapter 1.2.1 --- Cholesterol-lowering Effect of Phytosterols --- p.P.3 / Chapter 1.2.2 --- Anti-cancer Effect of Phytosterols --- p.P.5 / Chapter 1.2.3 --- Anti-proliferative Effect of Phytosterols --- p.P.5 / Chapter 1.3 --- Intake and Absorption of Phytosterols in Human Beings --- p.P.6 / Chapter 1.4 --- Occurrence and Physiological Levels of Phytosterol Oxidation Products (POPs) / Chapter 1.4.1 --- Occurrence of POPs --- p.P.8 / Chapter 1.4.2 --- Physiological Levels of POPs --- p.P.8 / Chapter 1.5 --- Endothelium and the Vascular Tone / Chapter 1.5.1 --- Role of Endothelium in the Control of Vascular Tone --- p.P.11 / Chapter 1.5.2 --- "Endothelial Dysfunction, Cholesterol Oxidation Products (COPs) and Phytosterol Oxidation Products (POPs)" --- p.P.12 / Chapter 1.6 --- Calcium Homeostasis in the Vascular Smooth Muscle Cells (VSMCs) / Chapter 1.6.1 --- Modes of Ca2+ Entry in VSMCs --- p.P.15 / Chapter 1.6.2 --- Modes of Ca2+ Efflux in VSMCs --- p.P.18 / Chapter 1.7 --- Objectives of the Study --- p.P.19 / Chapter CHAPTER TWO: --- β-SITOSTEROL OXIDATION PRODUCTS ATTENUATE VASORELAXATION BY INCREASING REACTIVE OXYGEN SPECIES AND CYCLOOXYGENASE-2 / Chapter 2.1 --- Introduction --- p.P.21 / Chapter 2.2 --- Materials and Methods / Chapter 2.2.1 --- Preparation of SOPs --- p.P.24 / Chapter 2.2.2 --- Gas Chromatography -mass Spectrometry (GC-MS) Identification of SOPs --- p.P.24 / Chapter 2.2.3 --- Analysis of SOPs --- p.P.25 / Chapter 2.2.4 --- Vessel Preparation --- p.P.25 / Chapter 2.2.5 --- Isometric Force Measurement --- p.P.26 / Chapter 2.2.6 --- Western Blotting --- p.P.27 / Chapter 2.2.7 --- Primary Culture of Rat Aortic Endothelial Cell --- p.P.28 / Chapter 2.2.8 --- Measurement of SOPs-induced Intracellular Oxidative Stress --- p.P.29 / Chapter 2.2.9 --- Drugs --- p.P.30 / Chapter 2.2.10 --- Data Analysis --- p.P.30 / Chapter 2.3 --- Results / Chapter 2.3.1 --- GC-MS Identification of SOPs --- p.P.32 / Chapter 2.3.2 --- Analysis of SOPs --- p.P.34 / Chapter 2.3.3 --- SOPs But Not β-Sitosterol Impaired ACh- and A23187-induced relaxations --- p.P.36 / Chapter 2.3.4 --- Inhibition of COX Pathway Reversed SOPs-induced Impairment in Relaxation --- p.P.39 / Chapter 2.3.5 --- SOPs Elevated Endothelial COX-2 Expression --- p.P.42 / Chapter 2.3.6 --- SOPs Increased COX-2 Expression via An Oxidative Stress-sensitive Pathway --- p.P.45 / Chapter 2.4 --- Discussion --- p.P.52 / Chapter 2.5 --- Conclusion --- p.P.56 / Chapter CHAPTER THREE: --- β-SITOSTEROL OXIDATION PRODUCTS POSSESS POTENTIAL VOCC BLOCKING EFFECT IN VSMCs / Chapter 3.1 --- Introduction / Chapter 3.1.1 --- 2+ Modes of Ca Entry and Efflux in Vascular Smooth Muscle Cells (VSMCs) --- p.P.57 / Chapter 3.1.2 --- Effect of Cholesterol and COPs on VSMCs --- p.P.57 / Chapter 3.2 --- Methodology and Materials / Chapter 3.2.1 --- Vessel Preparation --- p.P.59 / Chapter 3.2.2 --- Isometric Force Measurement iv --- p.P.59 / Chapter 3.2.3 --- Drugs --- p.P.60 / Chapter 3.2.4 --- Data Analysis --- p.P.61 / Chapter 3.3 --- Results / Chapter 3.3.1 --- SOPs but not β-Sitosterol Induced Relaxation in 60 mM K+ -preconstricted Endothelium-denuded Aorta --- p.P.62 / Chapter 3.3.2 --- Both SOPs and β-Sitosterol did not Relax U46619-preconstricted Endothelium-denuded Aorta --- p.P.64 / Chapter 3.3.3 --- Both SOPs and β-Sitosterol did not Relax PDA -preconstricted Endothelium-denuded Aorta --- p.P.66 / Chapter 3.3.4 --- SOPs Attenuated 60 mM K+-induced Contraction --- p.P.68 / Chapter 3.3.5 --- SOPs Attenuated Phenylephrine-induced Contraction --- p.P.70 / Chapter 3.3.6 --- Effect of SOPs on Concentration-dependent Responses to U46619 --- p.P.72 / Chapter 3.3.7 --- Preincubation with Bay K 8644 Abolished SOPs-induced Relaxation in 60 mM K+ -preconstricted Rings --- p.P.74 / Chapter 3.3.8 --- Preincubation with Thapsigargin did not Affect SOPs-induced Relaxation in 60 mM K+ -preconstricted Rings --- p.P.76 / Chapter 3.3.9 --- Preincubation with Ouabain did not Affect SOPs-induced Relaxation in 60 mM K+ -preconstricted Rings --- p.P.78 / Chapter 3.3.10 --- Preincubation with Nickel Potentiated SOPs-induced Relaxation in 60 mM K+ -preconstricted Rings --- p.P.80 / Chapter 3.4 --- Discussion --- p.P.84 / Chapter 3.5 --- Conclusion and Future Work --- p.P.88 / Chapter CHAPTER FOUR: --- INVOLEMENT OF NITRIC OXIDE IN THE PROTECTIVE EFFECTS OF PHYTOSTEROLS AGAINST HOMOCYSTEINE-INDUCED IMPAIRMENT OF ENDOTHELIUM-DEPENDENT RELAXATIONS OF RAT AORTA / Chapter 4.1 --- Introduction --- p.P.89 / Chapter 4.2 --- Materials and Method / Chapter 4.2.1 --- Vessel Preparation --- p.P.93 / Chapter 4.2.2 --- Isometric Force Measurement --- p.P.93 / Chapter 4.2.3 --- Western Blotting --- p.P.94 / Chapter 4.2.4 --- "1,1 -diphenyl-2-picrylhydrazyl (DPPH) Radical Scavenging Capacity" --- p.P.96 / Chapter 4.2.5 --- Primary Culture of Rat Aortic Endothelial Cells V --- p.P.96 / Chapter 4.2.6 --- Measurement Intracellular Oxidative Stress --- p.P.97 / Chapter 4.2.7 --- Nitric Oxide (NO) Measurement --- p.P.97 / Chapter 4.2.8 --- Drugs --- p.P.98 / Chapter 4.2.9 --- Data Analysis --- p.P.99 / Chapter 4.3 --- Results / Chapter 4.3.1 --- Impairment of Endothelium-dependent Relaxation by HC was Reversed by ROS Scavenger --- p.P.100 / Chapter 4.3.2 --- Brassicasterol Reversed HC-induced Endothelial Dysfunction In a Dose-dependent Manner --- p.P.102 / Chapter 4.3.3 --- β-Sitosterol and Stigmasterol Reversed HC-induced Endothelial Dysfunction --- p.P.104 / Chapter 4.3.4 --- Effects of β-Sitosterol Oxidation Products (SOPs) on HC-induced Endothelial Dysfunction --- p.P.106 / Chapter 4.3.5 --- Effects of Brassicasterol and β-Sitosterol on H2O2-induced Impairment of Endothelium-dependent Relaxation --- p.P.108 / Chapter 4.3.6 --- Phytosterols did not Directly Scavenge Free Radicals --- p.P.110 / Chapter 4.3.7 --- "HC and Brassicasterol did not Affect the Expression of SOD-1, SOD-2, eNOS, COX-1 and COX-2 in Aorta" --- p.P.112 / Chapter 4.3.8 --- HC Increased ROS Production in Primary Rat Aortic Endotelial Cells --- p.P.116 / Chapter 4.3.9 --- Brassicasterol did not Reverse the ROS Production by HC treatment In the Endothelial Cells --- p.P.120 / Chapter 4.3.10 --- Effect of L-NAME on Reversing the Effect of Brassicasterol on ACh-induced Relaxation --- p.P.123 / Chapter 4.3.11 --- Brassicasterol Reversed the Inhibitory Effect of HC on ACh-induced NO Production in Endothelial Cells --- p.P.125 / Chapter 4.4 --- Discussion --- p.P.128 / Chapter 4.5 --- Conclusion and Future Work --- p.P.132 / Chapter CHAPTER FIVE: --- CONCLUSIONS AND FUTURE WORK --- p.P.134 / Chapter CHAPTER SIX: --- REFERENCES --- p.P.137
70

Caracterização geoquímica orgânica em sedimentos presentes nos Pockmarks e Diápiros do talude sul do Brasil / Organic geochemical characterization in sediments present in the Pockmarks and Diapirs of the southern slope of Brazil

Doris Nagaoka 18 May 2018 (has links)
Os marcadores orgânicos moleculares (hidrocarbonetos alifáticos, esteróis e álcoois) em amostras de sedimentos superficiais e de testemunhos curtos coletados em diápiros e pockmarks localizados no talude sul do Brasil, foram utilizados para identificar as possíveis contribuições biogênicas (autóctones / alóctones). De modo geral, tanto nas amostras superficiais como ao longo dos testemunhos, o maior acúmulo de carbono orgânico total nos pockmarks foi observado, indicando o possível aprisionamento de sedimentos e de matéria orgânica no interior das concavidades. A presença de β-sitosterol, campesterol, álcoois e n-alcanos pesados, indicaram contribuições terrígenas para a área de estudo, que pode ser advinda da descarga continental do Rio da Prata, uma vez que a predominância terrígena é proveniente das pradarias, típica vegetação do Uruguai e do sul do Rio Grande do Sul. O transporte de sedimentos terrígenos ocorre em direção ao norte, ao longo da plataforma continental sul brasileira, pela Corrente Costeira do Brasil. A presença de detritos de fitoplâncton e zooplâncton também ocorre devido à influência dos nutrientes do Rio da Prata. As possíveis liberações de gás/fluido, que sustentaram ecossistemas quimiossintéticos em diferentes intervalos de dois testemunhos em pockmark e diápiro foram constatadas através da presença relativamente maior de n-alcanos leves com número par de carbonos. / Organic molecular markers (aliphatic hydrocarbons, sterols and alcohols) in superficial and short cores sediment samples collected in diapirs and pockmarks located in the southern slope of Brazil were used in order to identify the possible biogenic contributions (autochthonous / allochthonous). In general, in surface samples and throughout the cores samples, the greatest accumulation of total organic carbon in the pockmarks was observed, indicating the possible entrapment of sediments and organic matter inside the concavities. The presence of β-sitosterol, campesterol, alcohols and heavy n-alkanes indicated terrigenous contributions to the study area, which may be due to the continental discharge of Río de la Plata, since the terrigenous predominance is due to the prairies, a typical vegetation of Uruguay and the south of Rio Grande do Sul. The terrigenous sediments transport is carried through the North, along the Brazilian continental shelf, by the Coastal Stream of Brazil. The presence of phytoplankton and zooplankton debris is also due to the influence of the nutrients contribution from Río de la Plata. Possible gas / fluid releases, which sustained chemosynthetic ecosystems at different intervals of two pockmark and diaper cores, were verified by the relative predominance of even-numbered carbon n-alkanes.

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