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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.
31

Sintese enzimatica de lipidios estruturados : aplicação da tecnologia de membranas e CO2SC na obtenção e purificação / Enzymatic synthesis of structured lipids, application of membrane and SCCO2 technology for obtention and purification

Moura, Juliana Maria Leite Nobrega de 22 February 2006 (has links)
Orientador: Lireny Aparecida Guaraldo Gonçalves / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-05T16:44:27Z (GMT). No. of bitstreams: 1 Moura_JulianaMariaLeiteNobregade_D.pdf: 12204260 bytes, checksum: 81d1e3e2a50ff11707866a644a4ad381 (MD5) Previous issue date: 2006 / Resumo: Lipídios estruturados específicos (LE) constituem uma fonte lipídica de elevado valor nutricional em função das modificações ocorridas em sua composição e distribuição específica de ácidos graxos na molécula do glicerol, visando aplicações médicas, nutricionais e alimentícias. Este trabalho teve como objetivo a obtenção enzimática de LE a partir da interesterificação entre triacilgliceróis de cadeia média (TCM) e ésteres etílicos de ácidos graxos de cadeia longa (EEAGCL), aplicando a tecnologia de membranas, associada ou não à tecnologia de fluido supercrítico, durante a síntese e/ou purificação dos LE. As condições de obtenção dos EEAGCL, utilizados como substratos na obtenção dos LE, foram otimizadas através de planejamento experimental 23. Obteve-se taxa de conversão máxima de 95%, a 40°C, 1% de NaOH, 36% de etanol anidro, tempo de reação de 5 minutos e agitação de 600 rpm. Parâmetros reacionais como, diferentes valores de atividade de água (aw), uso de peneira molecular (10%p/p), razão molar de substratos de 1:2 e 1:4 (TCM/EEAGCL) e diferentes enzimas (Lipozyme TL 1Me RM 1M)foram avaliados na cinética de interesterificação do LE em reator por batelada, a 60°C. Verificou-se maior cinética para a enzima Lipozyme TL 1M,para aw entre 0,30 - 0,43 e razão molar de 1:4. O uso de peneira molecular (10% p/p) conferiu discreto aumento na incorporação de EEAGCL nos TCM. No sistema de reator de interesterificação piloto foram avaliados o efeito do condicionamento da enzima na mistura reacional (TCM + EEAGCL) e a influência da razão molar de substratos. A enzima agindo com aw original (0,33) conferiu maior incorporação quando comparada com a enzima previamente condicionada na mistura reacional, para 30 horas de reação, 67 e 48%, respectivamente. Quando se passou a razão molar dos substratos de 1:3 para 1:4 houve aumento no percentual de incorporação e o tempo necessário para a incorporação máxima no TCM (-66,6%) foi reduzido de 30 para 10 horas. A aplicação da tecnologia de membranas no sistema de obtenção enzimático de LE foi avaliada em reator de membrana plana (poliméricas) a 60°C, com agitação de 600 rpm, utilização da enzima Lipozyme TL 1M (5% peso/substrato) e razão molar de 1:3 - TCM/EEAGCLo. uso de membranas favoreceu a incorporação de EEAGCL nos TCM a partir de 54 horas de reação e ao final de 102 horas foi de 70 e 57%, com e sem membrana, respectivamente. Os teores de AGE w-6 e w-3 observados foram de 23,5 e 11,7%, respectivamente. No entanto, a razão entre os AGE ro-6/ro-3 não apresentou variação significativa. A associação do processo de membrana enzimática e fluidificação por dióxido de carbono supercrítico (C02SC) também foi avaliada. A enzima Candida antartica foi imobilizada por ligação covalente a uma camada de biopolímero (Gelatina/PEI), adsorvida na membrana tubular (aalumina). Os experimentos foram conduzidos a 60°C e pressão transmembrana de 0,05MPa. Pressões de C02 (PC02) de 6, 12 e 18MPa foram avaliadas. Verificou-se uma grande influência da PC02 sobre a cinética de interesterificação, tendo a PC02 de 18MPa permitido incorporação máxima de 34,5% de EEAGCL no TCM; dentre os quais 24,7% de ácidos graxos essenciais. Experimentos foram conduzidos com o objetivo de purificar o LE através da extração por C02SC dos subprodutos do meio reacional e retenção seletiva do LE através de membrana de osmose reversa. Foram avaliadas diferentes pressões de CO2 (9, 11 e 13MPa) e pressões transmembranas (1, 2, 3 e 4MPa), a 40°C. A membrana de osmose reversa BW-30 apresentou boa resistência às pressões utilizadas e maior retenção de triacilgliceróis nos testes seletivos. Incrementos na PC02 de 9 a 13MPa ocasionaram decréscimos no fator de retenção de triacilgliceróis devido ao aumento na solubilização dos solutos e consequente redução na seletividade da extração. O fator máximo de retenção de triacilgliceróis foi obtido com baixa PCO2 (9MPa) e baixa pressão transmembrana (0,7MPa). A membrana apresentou, no período de estabilização, um fator de retenção de triacilgliceróis médio de 95% e máximo a partir de 3 horas de filtração. A utilização de baixa temperatura (40°C) na extração e purificação do LE confere boa proteção aos ácidos graxos poliinsaturados contra a oxidação e migração acila / Abstract: Specific-structured lipids (SL) are a lipid source with high nutritional value due to changes in its glycerol backbone's fatty acid composition and specific distribution aiming medical, nutritional and food applications. This study had as objective the production of SL through enzymatic interesterification between medium chain triacylglycerol (MCT) and long chain fatty acid ethyl esters (LCFAEt) applying membrane technology, with or without supercritical fluid technology for synthesis and/or SL purification. The production conditions of LCFAEt, used to obtain SL, were optimized according to an experimental planning (23). Ethyl esters' conversion rate was 95%, at 40°C, 1% NaOH, 36% ethanol, running 5 minutes under 600rpm stirring speed. Reaction parameters like water activity (aw), moisture absorbent (10%w/w), molar ratio between substrates of 1:2 e 1:4 (MCT/LCFAEt) and types of enzymes (Lipozyme TL 1Mand RM 1M)were evaluated according to their influences on the SL interesterification in the batch reactor, at 60°C. The best incorporation results were obtained using Lipozyme TL 1Mwith aw between 0,30- 0,43.and molar ratio of 1:4. 10% (p/p) of moisture absorbent the interesterification kinetic presented a discreet increase. The impact of the enzyme conditioning process in the blend and the influence of the molar ratio of substrates were evaluated in the pilot reactor system. The usage of the enzyme with original water activity (0,33) provided higher kinetic incorporation in comparison with the conditioned enzyme, for a reaction time of 30 hours, 67 and 48%, respectively. The increase in the molar ratio of substrates from 1:3 to 1:4 improved the kinetic incorporation and reduced the maximum incorporation reaction time (66,6%) from 30 to 10 hours. The usage of membrane technology in the enzymatic system to obtain SL was evaluated in a plain membrane reactor (polymeric) under 60°C temperature; 600rpm stirring speed; Lipozyme TL 1M enzyme (5% based on substrates' weight) and molar ratio of substrates of 1:3(MCT/LCFAEt). The application of membranes increased the kinetic incorporation of LCFAEt in the MCT afier 54 hours of reaction. In the end of 102 hours incorporation was 70 and 57%, with and without membrane in the reactor, respectively. The final SL, obtained with and without membrane, showed fatty essential acids composition of 23,5 and 11,7%, respectively. However, the ratio between the essential fatty acids 00-6/00-3was not significantly different. The coupling of the membrane filtration process and fluidification by supercritical carbon dioxide (SCCO2) was also evaluated. The enzyme (Candida antartica) was immobilized on the membrane support (a-alumina) by covalent attachment to a gelatin/PEI layer previously adsorbed. Tests were performed at 60°C and O,O5MPa of transmembrane pressure. CO2 pressures (PCO2) of 6, 12 and 18MPa were evaluated. This parameter showed a high influence in the kinetic interesterification, with highest incorporation value of LCFAEt in the MCT (34,5%) at 18MPa, being 24,7% of essential fatty acids. Tests to purify the SL by SCCO2extraction of the undesired solutes and triacylglycerol retention by reverse osmosis and nanofiltration membrane were also performed. PCO2 of 9, 11 and 13MPa and transmembrane pressure of 1, 2, 3 and 4MPa were evaluated at temperature of 40°C. Reverse osmosis membrane (BW-30) demonstrated good resistance to the pressure conditions and higher triacylglycerol retention. The increment in the PCO2 from 9 to 13MPa reduced the triacylglycerol retention factor by increasing solute's solubilization. The highest triacilglicerol retention factor was obtained at the lowest PCO2 (9MPa) and at low transmembrane pressure (O,7MPa). The membrane showed, in the initial time, triacylglycerol retention factor of 95% and the maximum value with 3 hours of filtration. The low temperature (40°C) usage in SL extraction and purification reactions provided good protection to the polyunsaturated fatty acids against the oxidation and acyl migration / Doutorado / Doutor em Tecnologia de Alimentos
32

Óleo de soja na nutrição da tilápia-no-Nilo (Oreochromis niloticus) na fase de terminação / Soybean oil in nutrition of Nile tilapia (Oreochromis niloticus) in the finishing phase

Godoy, Antonio Cesar 27 February 2015 (has links)
Made available in DSpace on 2017-07-10T17:48:04Z (GMT). No. of bitstreams: 1 Antonio_Cesar_Godoy.pdf: 1296602 bytes, checksum: 2f9c21c86a5c20aae28ee9b79778df23 (MD5) Previous issue date: 2015-02-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The aim of this study was to evaluate the inclusion of different levels of soybean oil on the animal performance, hematological condition and evaluation of chemical composition of Nile tilapia fillets fed with increasing levels of soybean oil diets. 270 tilapia with average initial weight of 425.33 ± 32,37g and initial length of 25.53 ± 2.00 cm were used, at completely randomized design in 15 tanks. Diets were formulated to present isonitrogenous (30%) using different addition levels of soybean oil, a total of five treatments (0.00; 1.50; 3.00; 4.50 and 6.00%) and three replications. The parameters of zootechnical performance evaluated were: survival (S), daily weight gain (DWG) and feed conversion rate (FCR). The body parameters evaluated were: carcass yield (CY), fillet yield (FY), dressed out yield (DOY), visceral fat index (VFI) and hepatosomatic index (HSI). For hematological and biochemical parameters the concentrations of total protein mg/dL (TP), total cholesterol mg/dL (TC); glucose (GL), triglycerides (TG), hemoglobin, erythrocytes and hematocrit were analyzed. For the proximate studies nine fillets from each of the experimental units were used, in which it was determined the moisture (M), crude protein (CP), ether extract (EE) and ash (A). In animal performance, there were no statistical difference (p <0.05) for the daily weight gain (DWG), with higher value 4,13g.dia-1 and feed conversion (FC) with the lowest value (1.87) observed when included 4.50% soybean oil in the diet. Polynomial effect for carcass yield was observed and the highest value (90.07%) occurred in 3.95% soybean oil. The lowest value of the visceral fat index (VFI) obtained was 3.85% and the estimated polynomial effect LRP with 4.86% soybean oil addition. For the hepatosomatic index variable polynomial effect was observed with lower value (2.14%) to 3.22% soybean oil addition. The variable total cholesterol showed quadratic effect with the lowest value (117 mg.dL-1) at 0.80% soybean oil inclusion. The variable triglycerides showed LRP effect with the highest value (269.35 mg.dL-1) observed at 5.04% inclusion. Distinctions (p <0.05) were observed in crude protein and ether extract values with reduction to crude protein and increase of the ether extract with LRP effect for these variables in the near concentration of 4.50% soybean inclusion. In conclusion, data showed that diets with levels between 2.00 and 4.50% soybean oil inclusion allows better carcass yield (CY), daily weight gain (DWG), lower levels of visceral fat Index (VFI) and hepatossomatic index (HSI), also a deposition of intramuscular fat with consequent reduction in protein content / O objetivo desse estudo foi avaliar os diferentes níveis de inclusão de óleo de soja no desempenho zootécnico, condição hematológica e a avaliação da composição centesimal de files de tilápia-do-Nilo alimentadas com as dietas contendo níveis crescentes de óleo de soja. Foram utilizadas 270 tilápias com peso inicial médio de 425,33 ± 32,37g e comprimento inicial médio de 25,53 ± 2,00 cm, distribuídos inteiramente ao acaso em 15 tanques. As dietas foram formuladas de forma a apresentarem-se isoproteícas (30%) utilizando diferentes níveis de inclusão de óleo de soja, totalizando cinco tratamentos (0,00; 1,50; 3,00; 4,50 e 6,00%) e três repetições. Os parâmetros de desempenho zootécnicos avaliados foram: sobrevivência (SO), ganho em peso diário (GPD), conversão alimentar aparente (CAA). Os parâmetros corporais avaliados foram: rendimento de carcaça (RC), rendimento de file (RF), rendimento de tronco limpo (RTL), índice de gordura visceral (IGV) e índice hepatosomático (IHS). Para os parâmetros hematológicos e bioquímicos avaliou-se as concentrações de proteínas totais mg/dL (PT), colesterol total mg/dL (CT); glicose (GL), triglicerídeos (TG), hemoglobina, eritrócitos e hematócrito. Para as análises centesimais foram utilizados nove files de cada unidade experimental, onde foram determinados a umidade (UM), proteína bruta (PB), extrato etéreo (EE) e matéria mineral (MM). Nos parâmetros zootécnicos, houve diferença estatística (p<0,05) para ganho em peso diário (GPD), com maior valor de 4,13g.dia-1 e a conversão alimentar aparente (CAA) com o menor valor (1,87) observado quando incluído 4,50% de óleo de soja na dieta. Foi observado efeito polinomial para o rendimento de carcaça e o maior valor (90,07%) ocorreu com 3.95% de óleo de soja. O menor valor do índice de gordura visceral (IGV) obtido foi de 3,85% e estimado efeito polinomial LRP com 4,86% de inclusão de óleo de soja. Para a variável índice hepatosomático foi observado efeito polinomial com menor valor (2,14%) para 3,22% de inclusão de óleo de soja. A variável colesterol plasmático total apresentou efeito quadrático, com o menor valor (117 mg.dL-1) em 0,80% de inclusão de óleo de soja. A variável triglicerídeos, apresentou efeito LRP com o maior valor (269,35 mg.dL-1) observado em 5,04% de inclusão de óleo de soja. Pode-se observar distinções (p<0,05) nos teores de proteína bruta e extrato etéreo, com diminuição para proteína bruta e aumento para extrato etéreo com efeito LRP para estas variáveis na concentração próxima de 4,50% de inclusão. Conclui-se que dietas com teores entre 2,00 e 4,50% de inclusão óleo de soja, possibilitam melhores rendimento de carcaça (RC), ganho em peso diário (GPD), menor nível de Índice de Gordura visceral (IGV) e índice hepatosomático (IHS), também uma deposição de gordura intramuscular com consequente diminuição do teor de proteína
33

Stanovení mastných kyselin v lidských tkáních / Determination of fatty acids in human tissues

Turňová, Ivana January 2017 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Candidate: Ivana Turňová Supervisor of Diploma Thesis: Mgr. Monika Kuchařová, Ph.D. Consultant: prof. MUDr. Zdeněk Zadák, CSc. Title of Diploma Thesis: Determination of fatty acids in human tissues The fatty acids are non-negligible component of lipids as one of the basic nutrients. This thesis in its theoretical part presents above all the group of polyunsaturated fatty acids (PUFA), which are important structural units of the cell membranes, they are also the precursors to several significant biologically active substances. In the human organism PUFA participate in many physiological and pathological processes this way, where they cause the large spectrum of actions. Onwards the thesis describes the gas chromatography method that is used in chemical analysis of lipids for the fatty acid determination as the gold standard. Experimentally, the fatty acid representation was determined in the blood, muscle, heart, liver and kidney among 26 cadavers divided into two groups according to the presence/absence of inflammatory process at the time of death. The data obtained were statistically analysed. The results were descriptively evaluated and there were indicated possible explanations of differences...
34

Stanovení spektra mastných kyselin u pacientů podstupujících léčbu taxany / Determination of the fatty acids spectrum in patients undergoing treatment with taxanes

Kuříková, Barbora January 2018 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Author of Diploma Thesis: Bc. Barbora Kuříková Supervisor of Diploma Thesis: Mgr. Monika Kuchařová, Ph.D. Consultant: prof. MUDr. Zdeněk Zadák, CSc. Title of Diploma Thesis: Determination of the fatty acids spectrum in patients undergoing treatment with taxanes The diploma thesis deals with the determination of fatty acids spectrum in erythrocytes in patients treated with taxanes. The theoretical part describes general features of fatty acids, their synthesis and degradation. Then it is focused on the topic of breast cancer, taxane treatment and negative side effects associated with taxane treatment, especially polyneuropathy. The gas chromatography, which is commonly used in practice, is also described in this part. The experimental part is divided into three parts. The first part describes working process, chromatographic analysis and evaluation of this analysis. In the second part there is comparing of spectrum of fatty acids of patients without and with polyneroupathy. And in the last part there is a comparing of spectrum of fatty acids of patients before taxane treatment, closely after treatment and about month after the treatment. Results of the experimental part are evaluated at the end...
35

Fluktuace hladin mastných kyselin v tkáních náhle zemřelých osob a srovnání s hodnotami u patologických stavů / The fluctuation of fatty acids levels in the tissues of suddenly deceased persons and comparison with values in pathological states

Čunátová, Alena January 2020 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Candidate: Alena Čunátová Supervisor of Diploma Thesis: Mgr. Monika Kuchařová, Ph.D. Title of Diploma Thesis: The fluctuation of fatty acids levels in the tissues of suddenly deceased persons and comparison with values in pathological states Fatty acids and their metabolites are significantly involved in many physiological and pathological processes. This thesis monitors the levels of selected fatty acids in human tissues and the effect of long-term disease on their stores. In addition to the general characteristics, the theoretical part focuses on the intake of polyunsaturated fatty acids and their importance in the human body. It also deals with the effects of eicosanoids and other fatty acid metabolites. Methods used in fatty acid bioanalysis are also described. In the experimental part, the proportion of fatty acids in seven tissue types was compared between two groups of donors. One of them included 8 relatively young, healthy, suddenly deceased individuals. The second group included 12 elderly polymorbid patients. The obtained tissue samples were adjusted using extraction and derivatization techniques. Gas chromatography with flame ionization detection was used for analysis. The measured...
36

Stanovení hladin mastných kyselin ve vybraných tkáních / The determination of fatty acids level in chosen tissues

Kynclová, Kamila January 2021 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Candidate: Kamila Kynclová Supervisor of Diploma Thesis: Mgr. Monika Kuchařová, Ph.D. Title of Diploma Thesis: Determination of fatty acids levels in selected human tissues Fatty acid are an essential part of many metabolic processes in the body. The theoretical part of the the thesis presents primarily omega-3 and omega-6 fatty acids, their general characteristics, metabolism and their effect on various disease. The roles of fatty acid in cancer, neuropsychiatric and inflammatory diseases are described here. The thesis also mentions the method of gas chromatography, which was used to determine the levels of fatty acids. The experimental part of the thesis includes method, chromatographic analysis and results. 13 fatty acids in 7 different tissues were analyzed: subendocardial tissue, liver parenchymal tissue, kidney and adrenal tissue, skeletal muscle tissue, adipose and brain tissue. Tissues were collected from 20 healthy, suddenly deceased, cadavers. Donors were divided into two groups according to age. The obtained data were statistically processed and divided according to individual fatty acids. In the end the results between the two groups were evaluated with a possible explanation of the...
37

Assessing EPA + DHA requirements of Sparus aurata and Dicentrarchus labrax : impacts on growth, composition and lipid metabolism

Houston, Sam James Silver January 2018 (has links)
The gilthead seabream (Sparus aurata) and European seabass (Dicentrarchus labrax) require n-3 long-chain polyunsaturated fatty acids (LC-PUFA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), for optimal growth and health. Due to the rapid growth of global aquaculture the quantity of marine oils used in aquafeeds has been limited, yet the overall quantity of oil in an aquafeed has increased by the addition of vegetable oil (VO) to supply dietary energy. For aquaculture to continue to grow more fish must be produced with less marine ingredients, yet EPA and DHA must be maintained at levels above fish requirements. This project set out to re-evaluate the requirement for EPA and DHA in gilthead seabream and European seabass. Two dose-response studies were designed and executed where juvenile seabream and seabass were fed one of six levels of EPA+DHA (0.2 – 3.2 % as fed). Biometric data were collected and analysed to determine new requirement estimates for EPA+DHA for fish of two weight ranges (24 – 80 g and 80 – 200 g). The effects of the dietary LC-PUFA gradient on lipid composition and metabolism were also considered.
38

INFLUÊNCIA DO ÔMEGA 3 SOBRE SINTOMAS EXTRAPIRAMIDAIS, DEFICIÊNCIA COGNITIVA E PARÂMETROS DE ESTRESSE OXIDATIVO EM ANIMAIS TRATADOS COM NEUROLÉPTICOS

Barcelos, Raquel Cristine Silva 17 July 2009 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Haloperidol and fluphenazine are typical neuroleptics widely used in the treatment of mental illness, whose chronic use is associated with adverse effects that affect the motor function and memory, among others. The motor disturbances can be moderate, and include parkinsonism, akathisia, dystonia, but also a more severe syndrome, known as tardive dyskinesia (TD). Studies have shown that essential polyunsaturated fatty acids (EPUFAs) may affect physiological functions involved in movement and memory disorders through of the membrane phospholipid composition of neuronal cells. This study investigated the effects of supplementation of EPUFA (omega-3) on orofacial dyskinesia and memory dysfunction induced by haloperidol and fluphenazine, designated as experiment 1 and 2, respectively. In both experiments, male Wistar rats received in place of drinking water, a suspension with capsules of fish oil (FO), whose composition was determined by gas chromatography (EPA-20%, DHA- 6%, linolenic acid- 0, 4%), or vehicle (C). After 8 weeks of treatment, half the animals of each experimental group received a weekly administration of neuroleptic (12mg/kg/mL-im) (H-haloperidol or F-fluphenazine in experiments 1 and 2, respectively) or vehicle for 4 weeks. The intake of omega-3 ad libitum in the drinking water was maintained during this time. The animals were observed weekly for the quantification of orofacial dyskinesia (OD), (vacuous chewing movements frequency- VCM) in 7th, 14th, 21st and 28th days after the first dose of neuroleptic/vehicle. Immediately after each orofacial observation, the rats treated with neuroleptic (H and FO+H, experiment 1, F and FO+F, experiment 2) were submitted to catalepsy-time quantifications. In the last week of treatment, the rats of both experiments were previously trained for 4 consecutive days and submitted to memory test in water-maze task. On the 8th day after the last dose of neuroleptic/vehicle, the rats were sacrificed by exsanguinations (by cardiac puncture), with blood collection and removal of brain tissue (hippocampus and substantia nigra) for determination of lipid peroxidation. Data of OD (VCMs) and catalepsy time were analyzed by three-way and one way ANOVA with repeated measure, respectively, followed by Duncan s test (VCMs only) and paired T test; Data of water-maze task and assessments of lipid peroxidation (TBARs) were evaluated by two way ANOVA followed by Duncan s test. Statistical significances were considered for P <0.05 values for all assessments. The omega-3 decreased the motor disorders (VCMs and catalepsy time), the loss of memory and parameters of lipid peroxidation induced by neuroleptics, suggesting that these effects are related to the anti-apoptotic properties of EPUFAs. Our results emphasize the importance of including fatty acids n-3 from diet or its supplementation, which may prevent or reduce motor and memory disorders, often related to chronic treatment with typical neuroleptics, which until now has no effective treatment. / Neurolépticos típicos como haloperidol e flufenazina são amplamente empregados no tratamento das doenças mentais, cujo uso crônico está associado a efeitos adversos que afetam as funções motoras e de memória, entre outras. Os distúrbios motores podem ser mais brandos, e incluem tremores, acatisia, distonias, como também uma síndrome mais grave, a discinesia tardia (DT). Estudos têm demonstrado que os ácidos graxos poliinsaturados (AGPIs) podem afetar as funções fisiológicas envolvidas nos distúrbios do movimento e de memória, através da composição da membrana fosfolipídica das células neuronais. O objetivo deste estudo foi investigar os efeitos da suplementação dos AGPIs n-3 (ômega-3) sobre a discinesia orofacial e a disfunção de memória induzidas por haloperidol e flufenazina, designados como experimento 1 e 2, respectivamente. Em ambos os experimentos, ratos Wistar machos receberam no lugar da água de beber, uma suspensão com cápsulas de óleo de peixe (OP), cuja composição foi determinada através de cromatografia gasosa (EPA-20%, DHA 6%, ácido linolênico 0,4%), ou veículo (C). Após 8 semanas de tratamento, metade dos animais de cada grupo experimental receberam uma administração semanal de neuroléptico (12 mg/kg/mL;im) (H-haloperidol e F-flufenazina, nos experimentos 1 e 2 respectivamente) ou veículo por 4 semanas. Durante este tratamento a ingestão ad libitum de ômega-3 na água de beber foi mantida. Os animais foram semanalmente observados para a quantificação da discinesia orofacial (DO) (incidência de movimentos de mascar no vazio - VCM) no 7º, 14º, 21º e 28º dias após a primeira administração de neuroléptico ou veículo. Logo após cada observação orofacial, todos os animais tratados com neurolépticos (grupos H e OP+H, experimento 1; F e OP+F, experimento 2) foram submetidos à quantificação do tempo de catalepsia. Na última semana de tratamento, de ambos os experimentos foram submetidos ao teste de memória em water-maze , após 4 dias de treinamento. No 8º dia após a última administração de neuroléptico/veículo, os ratos foram sacrificados por exsanguínação (punção cardíaca), com coleta de sangue e retirada de tecidos cerebrais (substância-negra e hipocampo) para determinação de parâmetros de peroxidação lipídica. Os dados da DO (VCMs) foram analisados por ANOVA de três vias com medida repetida, seguida por teste de Duncan e teste T pareado; O tempo de catalepsia foi avaliado por ANOVA de uma via com medida repetida, seguida de teste T pareado; Resultados obtidos em paradigma de labirinto aquático e avaliações de peroxidação lipídica (TBARS) foram avaliados por ANOVA de duas vias seguida de teste de Duncan. Foram considerados significativos os valores de P<0.05, para todas as avaliações. O ômega-3 diminuiu as desordens motoras (VCM e tempo de catalepsia), os prejuízos de memória e parâmetros de peroxidação lipídica induzidos pelos neurolépticos, sugerindo que esses efeitos estão relacionados com as propriedades anti-apoptóticas dos ácidos graxos essenciais. Nossos resultados ressaltam a importância da inclusão de ácidos graxos n-3s na dieta ou através da sua suplemantação, os quais podem prevenir ou atenuar distúrbios motores e de memória, freqüentemente relacionados ao tratamento crônico com neurolépticos típicos, que até o momento não dispõe de um tratamento eficaz.
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Einflüsse essentieller Fettsäuren zusammen mit konjugierter Linolsäure auf Leistung, Stoffwechsel, Entzündungsparameter und oxidativen Stress bei Milchkühen

Haubold, Susanne 23 August 2021 (has links)
Einleitung: Futterrationen für Hochleistungsmilchkühe basieren häufig auf Maissilage und liefern somit nur wenig frisches Gras, was eine niedrige Zufuhr an n-3-Fettsäuren, v.a. an α-Linolensäure (ALA), bewirkt. Dies führt einerseits zu einem reduzierten Status an ALA und konjugierter Linolsäure (CLA) und andererseits zu einem hohen n-6/n-3-Verhältnis bei laktierenden Kühen. Ziel der Untersuchungen: Das Ziel der vorliegenden Studie war es, die Einflüsse einer Supplementierung von essentiellen Fettsäuren (EFA, v.a. ALA) zusammen mit CLA auf den Fett- säurestatus, die Leistung, auf das antioxidative und inflammatorische System bei Milchkühen, die mit einer Mais-basierten Ration gefüttert wurden, in etablierter Laktation zu untersuchen und ver- schiede Stoffwechselwege, einschließlich der somatotropen Achse, näher zu beleuchten. Tiere, Material und Methoden: Es wurden 4 Kühe (3. Laktation, 126 ± 4 Tage in Milch) in einem 4 × 4 Latin Square untersucht. Die Kühe erhielten täglich abomasale Infusionen an Kokosöl (CTRL, 38,3 g/d; v.a. gesättigte Fettsäuren), Lein- und Distelöl (EFA, 39,1 und 1,6 g/d), Lutalin® (cis-9,trans-11 und trans-10,cis-12 CLA, jeweils 4,6 g/d) oder EFA+CLA für jeweils 6 Wochen. Die initiale Dosis wurde jeweils nach 2 Wochen verdoppelt, was in 3 Dosierungen resultierte (Dosis 1, 2 und 3). Es schloss sich eine 3-wöchige Washout-Periode an. Den Kühen wurde eine Mais-basierte Ration mit einem hohen n-6/n-3-V erhältnis (11,3:1) gefüttert. Die Trockensubstanzaufnahme und die Milchleistung wurden täglich und die Milchzusammensetzung wöchentlich gemessen. Die Fettsäuremuster im Milchfett und im Blutplasma, Plasmakonzentra- tionen von Metaboliten und Hormonen sowie von Parametern des antioxidativen Systems und der Immunantwort (nur in Woche 0 und 6) wurden jeweils in Behandlungswoche 0, 2, 4 und 6 analysiert. Lebergewebe wurde zu Beginn der Studie und jeweils nach 6 Wochen Behandlung entnommen und der Energiestoffwechsel sowie Parameter des antioxidativen Systems und der Immunantwort wurden auf Ebene der Transkription untersucht. Die statistische Auswertung wurde mittels ANOVA und der MIXED Prozedur (repeated measurements) in SAS durchgeführt, wobei Behandlung, Dosis und deren Interaktion als fixe Effekte und die Laktationswoche als Kovariable dienten. Ergebnisse: Die jeweils infundierten Fettsäuren stiegen sowohl im Plasma als auch in der Milch dosisabhängig an. Das n-6/n-3-Verhältnis des Milchfetts lag in der CTRL- und in der CLA- Gruppe höher als in den beiden EFA-Gruppen. Die Energie-korrigierte Milch und das Milchfett nahmen dosisabhängig in den beiden CLA-Gruppen ab. Es gab einen Trend für eine höhere Energiebilanz in der CLA-Gruppe. Der Milchproteingehalt war in den beiden CLA-Gruppen niedriger als in der CTRL-Gruppe und die Milchharnstoffkonzentration sank in beiden CLA- Gruppen dosisabhängig ab. Die Citratkonzentration in der Milch stieg dosisabhängig in der CLA- Gruppe an. Die Aktivität der Glutathionperoxidase im Blutplasma war in der CTRL-Gruppe ge- ringer als in der EFA-Gruppe und die Plasmakonzentration von β-Carotin stieg in beiden EFA- Gruppen mit der Dosis an. Die Plasmakonzentration des Gesamtcholesterols stieg dosisabhängig in allen Gruppen, außer der CLA-Gruppe, an. Die Plasmakonzentration des High-density- lipoprotein-Cholesterols stieg in der CTRL-Gruppe an und lag höher als in der EFA- und der CLA-Gruppe, während die Konzentrationen des Low-density-lipoprotein-Cholesterols dosisab- hängig in der EFA- und der EFA+CLA-Gruppe anstiegen und höher als in der CLA-Gruppe waren. Die hepatische Genexpression der 3-Hydroxy-3-methylglutaryl-CoA Synthase 1 wurde in allen Gruppen hochreguliert und lag in der EFA+CLA-Gruppe am höchsten. Die Genexpression des sterol regulatory element-binding factor 1 zeigte einen Trend für die niedrigsten Werte in den beiden EFA-Gruppen. Die Expression des leberspezifischen growth hormone receptor 1A (GHR1A) tendierte zu einer Erhöhung in der EFA+CLA-Gruppe im Vergleich zur CTRL-Gruppe. Die insulin-like growth factor I (IGF-I)-Plasmakonzentration stieg in der CLA-Gruppe an und der Plasmaspiegel des insulin-like growth factor binding protein 2 (IGFBP-2) lag in der EFA+CLA- Gruppe niedriger als in der CTRL-Gruppe. Die Albumin- und Harnstoffkonzentrationen im Plasma waren in der CLA-Gruppe niedriger als in der CTRL-Gruppe. Schlussfolgerungen: Die Milchfettdepression und das erhöhte Milch-Citrat weisen auf eine redu- zierte de-novo-Fettsäuresynthese und einen verbesserten oxidativen Status in der Milch durch CLA-Supplementierung hin. Weder CLA- noch EFA-Gaben zeigten eindeutige Wirkungen auf den Entzündungsstatus bei den Milchkühen. Die Supplementierung von EFA und CLA hatte Ein- fluss auf den Cholesterol- und den Fettstoffwechsel sowie deren Regulierung. Der erhöhte IGF- I-Plasma-Spiegel in der CLA-Gruppe sowie die niedrigere IGFBP-2-Plasmakonzentration und die erhöhte Genexpression des GHR1A in der Leber der EFA+CLA-Gruppe deuten auf stimulierende Effekte auf die somatotrope Achse hin. Weiterhin scheinen CLA-Gaben auch den Proteinstoffwechsel von Milchkühen zu beeinflussen.
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Effects of Essential Fatty Acids and Conjugated Linoleic Acid Supplementation on Fatty Acid Pattern in Blood Plasma and Milk and on the Inflammatory Response in Dairy Cows from Late Gestation to Early Lactation

Gnott, Martina 13 November 2023 (has links)
This study investigated the effects of abomasal infusion of essential fatty acids, especially alpha-linolenic acid, and conjugated linoleic acid on their distribution in milk fat and blood plasma and on the plasma inflammatory response in dairy cows from late to early lactation. The most important essential fatty acids for ruminants are alpha-linolenic acid and linoleic acid. They are abundant in pasture which is nowadays reduced in the ration of dairy cows due to the replacement of fresh feeds by preserved diets. Conjugated linoleic acid is formed as a by-product during ruminal biohydrogenation of essential fatty acids and has been associated with positive effects on the energy metabolism and immune system. Forty rumen-cannulated Holstein Friesian cows were assigned to four treatment groups in their late second lactation. Prior to supplementation, cows were fed a total mixed rations with a low-fat content. In late gestation cows were abomasally treated with coconut oil, linseed and safflower oil, conjugated linoleic acid, or both. Performance data, milk composition and fatty acid pattern in milk and plasma as well as inflammatory response parameters in plasma were measured regularly. Furthermore, liver tissue was tested for the abundance of genes related to the inflammatory response.:TABLE OF CONTENTS ABBREVIATIONS 1. INTRODUCTION 2. LITERATURE OVERVIEW 2.1 Essential Fatty Acids and Conjugated Linoleic Acid 2.1.1 Essential Fatty Acids (EFA) 2.1.2 Conjugated Linoleic Acid (CLA) 2.1.3 EFA in Dairy Cow Nutrition 2.2 Fatty Acid Distribution in Blood, Erythrocyte Membranes, and Milk Fat 2.2.1 Plasma Lipids 2.2.2 EFA and CLA in Plasma Lipids 2.2.3 EFA and CLA in Erythrocyte Membranes 2.2.4 EFA and CLA in Milk Fat 2.3 Effects of EFA and CLA on Inflammatory Processes during the Transition Period 2.3.1 Metabolic and Immunological Challenges during the Transition Period 2.3.2 Effects of EFA on the Metabolism, Inflammatory- and Immune Response 2.3.3 Effects of CLA on the Metabolism, Inflammatory- and Immune Response 2.4 Scope of the Thesis 3. PUBLICATION 4. GENERAL DISCUSSION 4.1 Abomasal Infusion 4.2 Animal Performance 4.3 Distribution of EFA and CLA in Blood and Milk Fat 4.4 Effects of EFA and CLA on Plasma and Hepatic Acute Phase and Inflammatory Response 4.5 Conclusion and Practical Considerations 4.5.1 Summary of EFA effects 4.5.2 Summary of CLA effects 4.5.3 Summary of synergistic effects of EFA and CLA 4.5.4 Summary of Observations apart from Treatments and Practical Considerations 5. SUMMARY 6. ZUSAMMENFASSUNG 7. REFERENCES APPENDIX

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