La néphropathie diabétique (ND), principale cause d’insuffisance rénale chronique, est caractérisée par une dysfonction des podocytes rénaux. Cette dysfonction podocytaire peut être causée par une résistance à l’insuline induite suite à l’exposition des podocytes aux acides gras libres (AGL). L’un des mécanismes par lequel les AGL réduisent les actions de l’insuline serait l’activation de la voie de Mammalian target of rapamycin (mTOR). Les objectifs sont de caractériser les mécanismes de résistance à l’insuline par les AGL dans les podocytes et d’étudier l’implication de la voie du complexe mTORC1 menant à la ND dans un modèle de diabète de type 2. In vivo, la fonction et la pathologie rénale des souris diabétiques de type 2 (db/db) ont été évaluées. Des podocytes murins ont été cultivés pendant 96 h en conditions normales (5,6 mM, NG) ou élevées (25 mM, HG) de glucose avec ou sans palmitate (25 μM) pour les dernières 24 h. In vitro, les podocytes exposés en HG ont montré une diminution de l’activation d’Akt induite par l’insuline. Le palmitate seul a diminué de 50% l’activation d’Akt alors que la combinaison HG + palmitate a accentué cette diminution en la réduisant de 72%. Cette inhibition se ferait via la phosphorylation en sérine d’IRS1. En effet, en présence de palmitate, la phosphorylation d’IRS1 (ser307) est augmentée d’environ 2 fois. De plus, la phosphorylation d’IRS1 par le palmitate est corrélée à une augmentation de la phosphorylation de mTOR (ser2448) et de son substrat S6 (ser240/244). L’inhibition de la voie de signalisation de l’insuline par la voie mTOR serait due à l’activation de la PKC-α suite à une stimulation au palmitate. Pour ce qui est de mTORC2, la phosphorylation inhibitrice de Rictor (thr1135) augmente de 47% en présence de palmitate. In vivo, dans les souris db/db, l’augmentation des marqueurs de la ND (albuminurie, expansion du mésangium, hypertrophie du glomérule et expression de TGF-beta) est associée à une élévation de la p-mTOR, p-Rictor et de p-S6 dans les glomérules rénaux. En conclusion, le phénomène de résistance à l’insuline par les AGL dans les podocytes serait causé par l’activation de PKC-α/mTORC1 menant à la phosphorylation d’IRS1 en sérine 307, un mécanisme complémentaire aux actions de l’hyperglycémie, et contribuant de façon indépendante à la progression de la ND. De plus, l’inhibition du complexe mTORC2 contribue à la diminution de la signalisation de la voie de l’insuline. / Abstract : Diabetic nephropathy (DN) is the leading cause of chronic renal failure in diabetic patients and is characterized by the dysfunction of podocytes. Our laboratory has shown that hyperglycemia caused podocyte insulin unresponsiveness and cell death via the upregulation of PKC- and SHP-1, a tyrosine phosphatase. In contrast, free fatty acids (FFA)-induced insulin resistance in podocytes is not associated with SHP-1 expression. Thus, other signaling pathways could be implicated including the activation of the Mammalian target of rapamycin (mTOR) complexes pathway. The aim of this study was to investigate the insulin resistance mechanisms caused by FFA in podocytes leading to DN in type 2 diabetes. In vitro, cultured podocytes were exposed to normal (5.6 mmol/L; NG) or high glucose (25 mmol/L; HG) levels for 96 h and to palmitate (25 µmol/L) the last 24h with or without insulin stimulation (10 nmol/L). As previously showed, podocytes exposed to HG decreased Akt activation upon insulin stimulation. Palmitate treatment alone reduced insulin-induced Akt phosphorylation by 50% while a combination of palmitate and HG blunted Akt activation by 72%. The inhibition of Akt by palmitate was associated with the increase of PKC- activation leading to mTOR phosphorylation and its substrate S6. Moreover, the mTORC1 complex activation enhanced the serine 307 phosphorylation of IRS1 known to de-activate IRS1. Furthermore, palmitate also mediated the mTORC2 complex inhibition via the Thr1135 phosphorylation of Rictor. In vivo, the implication of mTORC1 complex in DN development was evaluated using 25 weeks old type 2 diabetes mice (db/db). Mice developed increased albuminuria, mesangial cell expansion and glomerular hypertrophy compared to non-diabetic mice, which correlated with the phosphorylation of mTOR, Rictor and S6. In conclusion, elevated FFA levels caused activation of PKC-/mTORC1 pathway and inhibition of mTORC2 leading to insulin resistance in podocytes and DN progression.

Les plastoglobules sont de petites particules localisées au niveau des plastes qui stockent des lipides neutres tels que les triacylglycérols (TAG), du tocophérol et des caroténoïdes. Leurs nombre et diamètre changent en fonction de l’espèce de plante, du type de plaste, du stade de développement et des conditions environnementales. Dans les chloroplastes, les plastoglobules sont liés physiquement aux thylacoïdes par une monocouche de lipides polaires en continuité avec le feuillet externe des thylacoïdes. Ceci suggère qu’il y a une dynamique d’échange de métabolites tels que les lipides entre les deux compartiments. Cependant, la composition lipidique des plastoglobules est mal décrite. L’objectif de ce travail a été d’établir la nature exacte des lipides des plastoglobules en condition de culture standard par TLC/GC-FID suivie d’une étude par LC-MS/MS. Ces travaux ont montré que les plastoglobules sont composés majoritairement d’acides gras libres et de phytyls esters. En plus des lipides neutres, ils sont composés de galactolipides, de la PC et du PG de composition spécifique, riche en acides gras saturés, différente de celle des thylacoïdes et de l’enveloppe. Le deuxième objectif a été de définir l’origine des lipides des plastoglobules par l’étude de la cinétique de marquage des lipides en condition de stress. Ainsi, pendant le stress, une partie des acides gras issus de la dégradation des galactolipides des thylacoïdes sera à l’origine de la formation des phytyl esters puis stockée dans les plastoglobules. En conclusion, ces résultats suggèrent la présence de micro-domaines au niveau des thylacoïdes qui favoriseraient la formation des plastoglobules. / Plastoglobules are small lipoprotein particles localized inside plastids. They are surrounded by a monolayer of polar lipids, proteins and they store neutral lipids such as triacylglycerol, carotenoids and tocopherol. During plastid development or in response to stress conditions, plastoglobules increase in number and size along with thylakoids disintegration, and reciprocally, their number and size decrease while thylakoids are developing. Plastoglobules are surrounded by a leaflet contiguous with the thylakoid outer leaflet and therefore share a physical link with thylakoids. This connection suggests exchange of molecules between these two compartments. The protein composition of plastoglobules is well known. However, the lipid composition of plastoglobules is still unknown. Thereby, the aim of our study is, at first, to establish the nature and the origin of plastoglobules from Arabidopsis and pea leaves. Using TLC/GC-FID analysis and by LC-MS/MS we identified nature of the lipids composing the plastoglobules. Moreover, doing pulse and chase analysis during stress condition, we obtained information about the origin of plastoglobules lipids. Our results show that plastoglobules are composed in majority from neutral lipids, principally free fatty acids and phytyl esters. Moreover, plastoglobules contain polar lipids such as galactolipids and phospholipids (PC and PG) have a specific lipid composition different from the thylakoid leaflet and envelope. In addition, during stress conditions plastoglobules store phytyl esters coming from fatty acids of galactolipides in degradation. To summarize, the specific composition of plastoglobules suggest that microdomains might exist in thylakoids that would favor plastoglobule formation.

Even though edible oils undergo refining processes to remove undesirable components, commercial oils still contain small amounts of minor components that can contribute to either prooxidant and antioxidant pathways which ultimately affect the quality of the oils. The objective of this research was to determine the role of free fatty acids and mono- and diacylglycerols on the oxidative stability of oil-in-water emulsions. Free fatty acids acted as a strong prooxidants in stripped soybean oil-in-water emulsions. Concentrations as low as 0.1% of the lipid accelerated lipid oxidation rate by both shortening the lag phase of lipid hydroperoxide and hexanal formation. The results showed that the most likely mechanisms for the prooxidant activity of free fatty acids is through their ability to increase the negatively charge on emulsion droplets that in turn could attract the cationic transition metals to the emulsion droplet surface where they can interact with lipid and thus promote oxidation. The prooxidant activity of free fatty acids was dependent on fatty acid type with lipid oxidation rates being in the order of linolenic < linoleic < oleic. Surprisingly, an increase in the degree of unsaturation of the free fatty viii acids lowered the ability of the free fatty acids to promote oxidation which may be due to their differences in geometric shape thus influencing their ability to access the emulsion droplet interface and increase the negative charge. Overall, free fatty acids are strong prooxidants in oil-in-water emulsions. This prooxidant activity is dependent not only on their concentration but also on the molecular structure of the fatty acid. Addition of mono- and diacylglycerols in oil-in-water emulsions showed an antioxidative effect in both non-stripped and stripped soybean oil. Addition of 1-monooleoylglycerol only had a small impact on the oxidative stability of non-stripped soybean oil-in-water emulsions but did inhibit lipid oxidation in emulsions prepared with stripped soybean. Much stronger antioxidant activity was observed upon the addition of 1,2-dioleoyl-sn-glycerol to both non-stripped and stripped soybean oil-in-water emulsions. Both lipid hydroperoxide and hexanal formation decreased with increasing 1,2-dioleoyl-sn-glycerol concentrations with 2.5% 1,2-dioleoyl-sn-glycerol almost completely preventing hydroperoxide and hexanal production over the course of the study. Overall, these results suggest that diacylglycerols could be an effective antioxidant in oil-in-water emulsions which possibility due to their ability to form a liquid crystal phase which could form a physical barrier that decreases interactions between unsaturated fatty acids in the emulsion droplet core and prooxidants or oxygen in the aqueous phase of the emulsion. However, the antioxidant mechanism of diacylglycerols is not currently understood and needs further investigation.

京都大学 / 新制・課程博士 / 博士(農学) / 甲第23253号 / 農博第2460号 / 新制||農||1085(附属図書館) / 学位論文||R3||N5343(農学部図書室) / 京都大学大学院農学研究科応用生命科学専攻 / (主査)教授 小川 順, 教授 阪井 康能, 教授 栗原 達夫 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM

Thesis (MSc)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Background:Obesity is a growing global burden; current studies have projected the prevalence of obese / overweight individuals to increase to ~1.35 billion by 2030. A number of factors contribute to cardiovascular diseases, of which the focus of this study is what effect an increased level of free fatty acids has on the flux through the hexosamine biosynthetic pathway (HBP). It has been widely proven that an increased flux through the HBP causes an increase in protein O-GlcNAcylation, which leads to increased reactive oxygen species (ROS) production as well as an increase in cell death (apoptosis). Methods: For the purpose of this study a cell model was used. H9c2 cardiomyoblasts were cultured in 5ml Dulbecco‟s Modified Eagles Medium (DMEM) supplemented with 10% foetal bovine serum and 1% penicillin-streptomycin. The cells were then exposed to 0.25mM monounsaturated fatty acid (oleic acid) for 24, 48 and 72 hours respectively. The cultured cells were then evaluated to assess the degree ROS production, overall O-GlcNAcylation and cell death (apoptosis and necrosis), using flow cytometry and immunofluorescence microscopy. Results: We found that oleic acid causes a significant decrease in ROS production at the 48 hour time point when analysed on the flow cytometer, which indicates that oleic acid is metabolized by the cells in a independent manner. Oleic acid also caused a significant decrease in cell death at all the time intervals. With regard to the HBP, oleic acid activates this pathway but causes downstream cardioprotective effects that do not necessarily occur along this pathway. Conclusion: This study explored whether a monounsaturated fatty acid, oleic acid, is able to act as a novel cardioprotective agent. The in vitro data supports this concept and we showed that it is able to blunt oxidative stress and cell death. It was also found that although oleic acid activated the HBP, it did not mediate its protective effects via this pathway only. / AFRIKAANSE OPSOMMING: Agtergrond: Vetsug is 'n groeiende wêreldlas; huidige studies voorspel dat die voorkoms van vetsugtige / oorgewig individue toe sal neem tot ~1.35 biljoen teen 2030. Alhoewel verskeie faktore tot kardiovaskulêre siektes bydra is die fokus van hierdie studie om die effek van verhoogde vryvetsuurvlakke op die fluks deur die heksosamienbiosintestiese weg (HBW) te ondersoek. Dit is reeds bewys dat verhoogde fluks deur die HBW 'n verhoging in proteïen O-GlcNAsilering lei, wat verder tot verhoogde reaktiewe suusrtofspesies (ROS) vorming aanleiding gee en ook seldood (apoptose) verhoog. Metodes:'n Selmodel is vir die doel van hierdie studie gebruik. H9c2 kardiomioblaste is in 5ml Dulbecco's Modified Eagles Medium (DMEM) gekweek en gesupplementeer met 10% fetale beesserum en 1% penisillien-streptomysien. Die selle is blootgestel aan 'n 0.25mM mono onversadigde vetsuur (oleïensuur ) vir 24, 48 en 72 uur onderskeidelik. Die gekweekte selle is gevolglik ondersoek vir die graad van ROS ontwikkeling, algehele O-GlcNAsilering en seldood (apoptosis en nekrose), deur van vloeisitometrie en immunofluoresensie mikroskopie gebruik te maak. Resultate: Ons het bevind dat oleïensuur 'n betekenisvolle verlaging in ROS ontwikkeling teen 48 uur soos bepaal deur die vloeisitometer, veroorsaak. Dit wys daarop dat oleïensuur deur die selle op 'n onafhanklike wyse gemetaboliseer is. Oleïensuur het ook 'n betekenisvolle verlaging in seldood by alle tydsintervalle veroorsaak. Met betrekking tot die HBW het oleïensuur hierdie weg geaktiveer maar afstroom kardiobeskermings effekte versoorsaak wat nie noodwendig langs hierdie weg onstaan nie. Gevolgtrekking:Hierdie studie het die moontlikheid van 'n mono-onversadige vetsuur, oleïensuur, om op te tree as 'n nuwe kardiobeskermingsmiddel ondersoek. Die in vitro data ondersteun hierdie konsep en hier is aangetoon dat dit wel oksidatiewe stres en seldood onderdruk. Daar is verder bevind dat alhoewel oleïensuur die HBW aktiveer dit nie die beskermings effekte alleenlik via hierdie weg medieer nie.

A caseína e os ácidos graxos livres (AGL) são importantes componentes do leite relacionados às suas características industriais e sensoriais. Alguns fatores são responsáveis por alterações em suas concentrações, dentre eles, pode-se destacar as condições de armazenamento, além da agitação e, principalmente, a contagem de células somáticas (CCS). Para estudar tais alterações, avaliou-se através do presente estudo o efeito da temperatura de armazenamento (- 20oC e 7oC) e da idade das amostras (3, 6, 9 e 12 dias), assim como da CCS (CCS1: 400 mil, CCS2:400-750 mil e CCS3: 750 mil células somáticas/mL de leite). O efeito das condições de armazenamento sobre a caseína e os AGL foi avaliado no primeiro estudo. O efeito da CCS sobre a caseína e os AGL, por outro lado, foi avaliado no segundo estudo. No primeiro estudo, observou-se aumento nos teores de AGL ao longo do tempo, ou seja, acompanhando o aumento do período de armazenamento, com médias superiores em amostras resfriadas (7oC), em relação às congeladas (-20oC). Desta forma, sugere-se que análises laboratoriais devem ser realizadas em até três dias para este componente, devido ao seu aumento progressivo em amostras resfriadas. Para a caseína, entretanto, não foi identificada interação entre os fatores idade e temperatura. As médias deste componente não diferiram considerando-se as condições de armazenamento avaliadas, indicando que as análises para este componente podem ser realizadas até doze dias após a coleta, independente da temperatura de armazenamento. No segundo estudo, identificou-se interação entre classes de CCS e época de coleta, para caseína. A partir dos resultados de AGL, pode-se concluir que o leite encontra-se com altas concentrações deste componente, quando coletado na propriedade rural, sendo também observada influência da CCS sobre as concentrações de caseína e AGL no leite cru. Os AGL apresentaram incrementos significativos comparando-se amostras coletadas em diferentes locais, no trajeto da fazenda à indústria. Por outro lado, comparando-se os mesmos locais: tanque, rota e silo, as médias de caseína não diferiram. Observou-se correlação entre as variáveis CCS e caseína e CCS e AGL. / The casein and the free fatty acids (FFA) are important milk components related to its industrial and sensory characteristics. Some factors are responsible for changes in their concentration among them can highlight the storage conditions, as well as agitation and, especially, the somatic cell count (SCC). To study such changes, we assessed through the present study the effect of storage temperature (-20oC and 7oC) and the age of samples (3, 6, 9 e 12 days), as well as the CCS (CCS1: 400 mil; CCS2: 400-750 mil; CCS3: 750 mil somatic cells/mL of milk). The effect of CCS storage conditions on casein and FFA was evaluated in the first study. The effect of CCS on casein and FFA moreover, was evaluated in the second study. In the first study, it was observed increased levels the AGL over time, ie, accompanying the increase of the storage period, with means higher in refrigerated samples (7oC), in relation to frozen samples (- 20oC). Thus, it is suggested that laboratory examinations shall be performed up to three days to this component, due to their progressive increase in refrigerated samples. For casein, however, was not identified interaction between the factors age and temperature. The mean of this component did not differ considering the storage conditions, indicating that the analyzes for this component can be made until twelve days after collection, regardless of storage temperature. In the second study, we identified interactions between CCS classes and seasons, for casein. From the FFA results, we can conclude that milk meets with high concentrations of this component, when collected in the rural property, being also observed influence of CCS on concentrations of casein and FFA in raw milk. The FFA showed significant increases compared to samples collected at different locations on the path from farm to industry. On the other hand, comparing the same locations, tank, route and silo, the casein average did not differ. Correlation was observed between the variables casein and CCS and FFA and CCS.

Alterações metabólicas são muito frequentes em doentes graves. Sepse grave e choque séptico são condições clínicas muito prevalentes em unidades de terapia intensiva (UTI). A mortalidade da sepse grave e, especialmente do choque séptico, persiste alta, apesar das terapêuticas desenvolvidas nas últimas décadas. Controle rigoroso da glicemia parece ser uma terapia adjuvante muito importante, especialmente em doentes cirúrgicos graves. Ainda há controvérsias sobre o controle glicêmico rigoroso em doentes clínicos. Além da hiperglicemia, alguns estudos procuraram associar distúrbios no metabolismo de lipoproteínas e pior prognóstico para doentes graves. Também foi descrita a associação de hiperglicemia e quantidades mais baixas de lipoproteínas, sugerindo, possivelmente, o controle glicêmico rigoroso como fator importante para correção dos distúrbios do metabolismo de lipoproteínas. Neste estudo, dosamos LDL, HDL, triglicerídeos, colesterol total, ácidos graxos livres e Ox-LDL em 63 pacientes com diagnóstico de sepse grave ou choque séptico, divididos em dois grupos, sendo um grupo mantendo controle glicêmico rigoroso e outro grupo mantendo um controle glicêmico mais liberal, com internação em unidade de terapia intensiva (UTI) nas primeiras 72 horas de internação. Independentemente do grupo alocado, as concentrações séricas de LDL, HDL, colesterol total estiveram abaixo dos valores considerados normais. De outro modo, as concentrações séricas de ácidos graxos livres, triglicérides e Ox-LDL estiveram acima dos valores considerados normais. Ao longo das 72 horas houve manutenção das concentrações séricas de HDL e de colesterol total e das concentrações séricas elevados de ox-LDL e triglicérides. Houve um aumento progressivo das concentrações séricas de LDL e diminuição das concentrações séricas de ácidos graxos livres mais pronunciada nos doentes submetidos a controle glicêmico rigoroso. Ao longo do período de estudo, os pacientes sobreviventes apresentaram menores necessidades de insulina exógena, porém com concentrações séricas glicêmicas similares. As dosagens de Ox-LDL, LDL, HDL e PCR permaneceram similares entre os sobreviventes e os não sobreviventes / Metabolic disturbances are very frequent among critical care patients. Severe sepsis and septic shock are clinical conditions responsible for a great number of patients admitted to ICU. Severe sepsis and septic shock mortality rates remain high instead of new approaches developed in last decades. Intensive glycemic control appeared to be an important adjuvant therapy, especially among surgical intensive care patients. There are still some controversies about the benefits of intensive glycemic control among clinical intensive care patients. Beyond hyperglycemia, some studies have tried to associate lipid metabolism disturbances to worse prognosis. There are also descriptions of association between hyperglycemia and lower lipoproteins levels, suggesting the possible positive effects of intensive glycemic control and better control of lipid disturbances. In this study, we collected sequential serum LDL, HDL, triglycerides, total cholesterol, free fatty acids and Ox-LDL for 63 patients diagnosed as severe sepsis or septic shock admitted to ICU, in the first 72 hours after beginning of the symptoms. Patients were randomly allocated into two different groups, one for intensive glycemic control and the other maintaining more liberal glycemic levels. Results: Serum levels of LDL, HDL, and total cholesterol were below levels considered normal in both groups. Contrary, serum levels of free fatty acids, triglycerides and Ox-LDL were above normal levels in both groups. Along initial 72 hours we noticed a clear increase in LDL serum levels and decrease in free fatty acids serum levels more pronounced in the intensive glycemic control group. Survivors needed less dosages of exogenous insulin, despite of similar glycemic levels. Serum levels of Ox-LDL, LDL, HDL and CRP were similiar for survivors and non-survivors

O emprego de solventes no processo de obtenção de óleos de sementes oleaginosas é um processo amplamente empregado, sendo o hexano o solvente tradicionalmente adotado. O objetivo principal desta dissertação de mestrado foi avaliar a viabilidade da substituição do hexano por etanol no processo de extração de óleo de soja. A utilização de etanol apresenta vantagens bastante atrativas como: menor toxicidade, boa seguridade operacional além deste ser obtido de fonte biorenovável. A produção de etanol em larga escala no Brasil torna, ainda, o processo vantajoso do ponto de vista econômico, além de ser um solvente facilmente recuperado para posterior reutilização no processo devido às suas características físico-químicas. Desta forma, neste trabalho foram realizados experimentos de cinética de extração e experimentos de extração sólido-líquido na condição de equilíbrio, nos quais foram avaliadas as variáveis: temperatura (40 a 90 &deg;C) e hidratação do solvente (0 a 12%). Através da execução destes experimentos e a avaliação estatística dos resultados foi possível determinar os rendimentos de óleo e proteína, monitorar o comportamento dos compostos minoritários (ácidos graxos livres) e da água presente na matéria-prima, avaliar a qualidade da fração proteica resultante do processo de extração, além da composição química dos óleos obtidos. Assim, os resultados mostraram que o aumento do teor de água no etanol suprimiu fortemente a extração de óleo enquanto que a elevação da temperatura favoreceu a extração. Já a proteína exibiu um comportamento contrário ao óleo, sendo que o aumento da hidratação do solvente elevou a extração destes compostos e o aumento da temperatura diminuiu o teor de proteínas na fase extrato. Quanto à hidratação da fase extrato, pôde-se notar que esta foi independente da temperatura e que existe um equilíbrio entre a umidade do sólido e o nível de hidratação do etanol. A elevação da temperatura também aumentou a extração de ácidos graxos livres e a avaliação do perfil químico e da composição em AGL dos óleos obtidos via etanol mostrou que estes apresentaram composição típica de óleo de soja, independente da condição adotada. A qualidade da fração proteica resultante da extração do óleo, avaliada na forma de solubilidade de nitrogênio e análise térmica (DSC), mostrou que a proteína também foi fortemente influenciada pela presença da água no solvente e pelo aumento da temperatura, apresentando menores valores de solubilidade conforme o aumento do teor de água no etanol e da temperatura do processo. Diante dos resultados, pode-se inferir que é viável tecnicamente a utilização de etanol no processo de extração de óleo de soja, no entanto as condições de hidratação do solvente e temperatura devem ser consideradas devido à influência destas sobre as características da fração proteica do farelo desengordurado. / The use of solvents in the extraction of oil from oilseeds is a widely employed process and the hexane is the solvent traditionally adopted. The aim of this work was to evaluate the feasibility of replacing hexane by ethanol in the soybean oil extraction process. The use of ethanol has very attractive advantages such as: low toxicity, good operational security, as well as being obtained from a biorenewable source. The large scale production of ethanol in Brazil also makes the process advantageous from the economics point of view, besides being a solvent easily recovered for reuse in the process due to its physicochemical characteristics. Thus, in this work were performed experiments of kinetics of extraction and experiments of solid-liquid extraction in equilibrium condition in which the variables evaluated were: temperature (ranging from 40 to 90 &deg;C) and solvent hydration (0 to 12% of water). The accomplishment of these experiments and the statistical evaluation of the results made possible to determine the yields of oil and protein, monitor the behavior of minor compounds (free fatty acids) and of the water present in raw material, evaluate the quality of the protein fraction resulting from oil extraction process, and the chemical composition of the extracted oils. Then, the results showed that increasing in water content of ethanol suppresses strongly the extraction of oil while the increase of temperature increases the extraction. About protein, it exhibits an opposite behavior to the oil, with the rise in water content of the solvent increasing the extraction of such compounds and the rise of temperature decreases in the protein content of extract phase. Regarding the hydration of the extract phase, it can be seen that this is temperature independent and that there is equilibrium between the solid matrix and the moisture level of the solvent ethanol. The increase in temperature also increases the extraction of free fatty acids and the evaluation of the chemical profile and composition in FFA of oils obtained via ethanol showed that they had typical composition of soybean oil, regardless the condition adopted. The quality of the protein fraction resulting from oil extraction evaluated as nitrogen solubility and thermal analysis (DSC) showed that the protein is also strongly influenced by the presence of water in the solvent and by increasing the temperature, with lower values of solubility with increasing water content in the ethanol and the process temperature. From the results, it can be inferred that it is technically feasible to use ethanol in the soybean oil extraction process, however hydration conditions of the solvent and temperature must be considered due to the influence of these on the protein fraction characteristics of the defatted meal.

Alterações metabólicas são muito frequentes em doentes graves. Sepse grave e choque séptico são condições clínicas muito prevalentes em unidades de terapia intensiva (UTI). A mortalidade da sepse grave e, especialmente do choque séptico, persiste alta, apesar das terapêuticas desenvolvidas nas últimas décadas. Controle rigoroso da glicemia parece ser uma terapia adjuvante muito importante, especialmente em doentes cirúrgicos graves. Ainda há controvérsias sobre o controle glicêmico rigoroso em doentes clínicos. Além da hiperglicemia, alguns estudos procuraram associar distúrbios no metabolismo de lipoproteínas e pior prognóstico para doentes graves. Também foi descrita a associação de hiperglicemia e quantidades mais baixas de lipoproteínas, sugerindo, possivelmente, o controle glicêmico rigoroso como fator importante para correção dos distúrbios do metabolismo de lipoproteínas. Neste estudo, dosamos LDL, HDL, triglicerídeos, colesterol total, ácidos graxos livres e Ox-LDL em 63 pacientes com diagnóstico de sepse grave ou choque séptico, divididos em dois grupos, sendo um grupo mantendo controle glicêmico rigoroso e outro grupo mantendo um controle glicêmico mais liberal, com internação em unidade de terapia intensiva (UTI) nas primeiras 72 horas de internação. Independentemente do grupo alocado, as concentrações séricas de LDL, HDL, colesterol total estiveram abaixo dos valores considerados normais. De outro modo, as concentrações séricas de ácidos graxos livres, triglicérides e Ox-LDL estiveram acima dos valores considerados normais. Ao longo das 72 horas houve manutenção das concentrações séricas de HDL e de colesterol total e das concentrações séricas elevados de ox-LDL e triglicérides. Houve um aumento progressivo das concentrações séricas de LDL e diminuição das concentrações séricas de ácidos graxos livres mais pronunciada nos doentes submetidos a controle glicêmico rigoroso. Ao longo do período de estudo, os pacientes sobreviventes apresentaram menores necessidades de insulina exógena, porém com concentrações séricas glicêmicas similares. As dosagens de Ox-LDL, LDL, HDL e PCR permaneceram similares entre os sobreviventes e os não sobreviventes / Metabolic disturbances are very frequent among critical care patients. Severe sepsis and septic shock are clinical conditions responsible for a great number of patients admitted to ICU. Severe sepsis and septic shock mortality rates remain high instead of new approaches developed in last decades. Intensive glycemic control appeared to be an important adjuvant therapy, especially among surgical intensive care patients. There are still some controversies about the benefits of intensive glycemic control among clinical intensive care patients. Beyond hyperglycemia, some studies have tried to associate lipid metabolism disturbances to worse prognosis. There are also descriptions of association between hyperglycemia and lower lipoproteins levels, suggesting the possible positive effects of intensive glycemic control and better control of lipid disturbances. In this study, we collected sequential serum LDL, HDL, triglycerides, total cholesterol, free fatty acids and Ox-LDL for 63 patients diagnosed as severe sepsis or septic shock admitted to ICU, in the first 72 hours after beginning of the symptoms. Patients were randomly allocated into two different groups, one for intensive glycemic control and the other maintaining more liberal glycemic levels. Results: Serum levels of LDL, HDL, and total cholesterol were below levels considered normal in both groups. Contrary, serum levels of free fatty acids, triglycerides and Ox-LDL were above normal levels in both groups. Along initial 72 hours we noticed a clear increase in LDL serum levels and decrease in free fatty acids serum levels more pronounced in the intensive glycemic control group. Survivors needed less dosages of exogenous insulin, despite of similar glycemic levels. Serum levels of Ox-LDL, LDL, HDL and CRP were similiar for survivors and non-survivors

Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-09-16T14:17:18Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação_Andréa Leão_Ver_Final.pdf: 2849890 bytes, checksum: cd4d0770cfce99861e2cf216c67ed0fb (MD5) / Made available in DSpace on 2016-09-16T14:17:18Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação_Andréa Leão_Ver_Final.pdf: 2849890 bytes, checksum: cd4d0770cfce99861e2cf216c67ed0fb (MD5) Previous issue date: 2016-02-23 / ANP / O presente estudo propõe a separação entre os triacilgliceróis (TAGs), principais constituintes dos óleos vegetais, e ácidos graxos livres (AGLs) através do processo de destilação a vácuo. A possibilidade dessa separação consiste na considerável diferença de volatilidade entre os AGLs e os TAGs. Foram preparadas misturas modelo aos óleos residuais, ou seja, combinações em diferentes proporções em massa de óleo de soja refinado (OS) e o reagente ácido oleico p.a (AO). As misturas foram destiladas nas pressões reduzidas de 0,13; 0,40; 0,67 e 1,33 kPa, sendo o processo realizado em batelada em um único estágio, sem refluxo. As amostras foram caracterizadas antes e após o processo de destilação a vácuo quanto: à massa específica, ao teor de água, ao teor de AGL (%) e à composição de ácidos graxos por cromatografia gasosa. Posteriormente, foram definidos os componentes modelo de TAG e AO e a estimativa dos parâmetros termofísicos das misturas para a simulação do processo de destilação a vácuo no software Aspen Plus V8.8, utilizando tanques flash não adiabáticos em série. O modelo termodinâmico usado foi o Non-Random Two-Liquid (NRTL). As curvas de destilação experimentais da mistura de 89,45% de OS e 10,55% de AO em massa foram melhor representadas pelas curvas de destilação simuladas, apresentando o percentual de desvios médios quadráticos de 2,5; 2,2; 2,4 e 2,5% para operações realizadas em pressões reduzidas de 0,13; 0,40; 0,67 e 1,33 kPa, respectivamente. Os dados de massa específica a 20°C dos produtos das destilações, resíduos e destilados, foram semelhantes aos do OS e AO, respectivamente. Os teores de água dos destilados (0,024% a 0,059%) e dos resíduos (0,001% a 0,014%) estão em níveis adequados para o emprego das reações de esterificação e transesterificação para a produção de biodiesel. Os teores de ácidos graxos livres dos resíduos obtidos após as destilações ficaram dentro da faixa de 0,4% a 1,2%, indicando processo de separação por destilação a vácuo efetivo. / This study proposes the separation of triacylglycerols (TAG), main constituent of vegetable oils, and free fatty acids (FFA) through the vacuum distillation process. The possibility of this separation is the considerable difference in volatility between the FFA and the TAG. Mixtures were prepared with model waste oil, or combinations of different mass ratios of refined soybean oil (SO) and the reagent oleic acid (OA). The mixtures were distilled at reduced pressures of 0.13; 0.40; 0.67 and 1.33 kPa, the process being carried out in batches in a single stage, without reflux. The samples were characterized before and after the vacuum distillation process as: the specific gravity, the water content, the FFA content (%) and the fatty acid composition by gas chromatography. Subsequently, the components were defined template TAG and OA and the estimation of parameters of mixtures thermophysical to simulate the vacuum distillation process in Aspen Plus v8.8 software using non-adiabatic flash tanks in series. The thermodynamic model used was the Non-Random Two-Liquid (NRTL). Experimental distillation curves of mixing 89.45% of SO and 10.55% of mass OA were best represented by simulated distillation curves, showing the percentage of mean deviation squared of 2.5; 2.2; 2.4 and 2.5% for operations in reduced pressures of 0.13; 0.40; 0.67 and 1.33 kPa, respectively. The specific mass of data at 20°C the distillation of the products, residues and distillates were similar to SO and OA, respectively. The content of distilled water (0.024% to 0.059%) and waste (0.001% to 0.014%) were at adequate levels for the use of esterification and transesterification reactions for biodiesel production. The contents of free fatty acids from residues obtained after distillations were within the range of 0.4% to 1.2%, indicating a separation process by distillation under vacuum effective.