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Lipid oxidation in a model system and in meatArnold, Andrew Richard January 1989 (has links)
Lipid oxidation is the main factor which limits the shelf-life of meat when held under frozen storage. Research undertaken used pork phospholipid liposomes as a model for studying lipid oxidation in meat. Oxidation was followed by monitoring the decrease in the phospholipid unsaturated fatty acyl chains. It was found that the greater the level of unsaturation of the phospholipid fatty acyl chain the greater was their susceptibility to peroxidation. However, the results were not consistent and several reasons for the variation in rate are provided. At ambient temperatures copper (II) was found to be pro-oxidant in the peroxidation of liposomes. At temperatures below 0°C the prooxidant activity of copper (II) was significantly reduced. However copper again became highly pro-oxidant if sodium chloride was present. It is suggested that salt controls the copper ion concentration at sub-zero temperatures as the pro-oxidant activity of copper (II) is reduced on increasing the copper (II) concentration from 0.9 to 90 ppm. Other experiments found sodium nitrite and pholyphosphate to act as antioxidant and that liposome structure was an important factor in the rate of peroxidation. Four storage trials on pork burgers were undertaken to determine whether salt was also pro-oxidant in the stability of pork when held under frozen storage. The oxidative deterioration of the meat was followed by the following methods of analysis:- 1. The decrease in the unsaturated acyl chains of both total lipid and phospholipid. 2. The change in the colour parameters of the meat using reflectance spectroscopy. 3. The analysis of neutral lipid oxidation products by HPLC. 4. The organoleptic qualities of the pork using a trained panel of food assessors. The results from these storage trails showed that the deterioration of pork was minimised by storing the burgers at lower temperatures within the range 0 to -30°C. Salt was found to accelerate the oxidative deterioration of both uncooked and cooked pork when stored at -20°C. Nitrite was found to exhibit some antioxidant behaviour and reduce the pro-oxidant effect of salt.
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Effect of dietary fatty acids, time of feeding and immune response in poultry /Gonzalez, Dulmelis. January 2008 (has links)
Thesis (M.S.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 104-111). Also available on the World Wide Web.
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Effect of Dietary Omega-3 and Omega-6 Polyunsaturated Fatty Acids on Alcoholic Liver DiseasePurwaha, Preeti January 2012 (has links)
PUFAs have been shown to modulate ALD by several mechanisms, including free radical generation from hepatic lipid peroxidation. However, how they modulate lipid peroxidation and generation of bioactive metabolites in ALD is poorly understood and it is still not clear which PUFAs (ω-3 or ω-6) are beneficial or detrimental in ALD. Thus, our objective was to study the effect of ω-3/ω-6 PUFAs on lipid peroxidation and ethanol mediated steatosis and inflammation. Using standard liquid diet (LDC), LDC with fish oil (rich in ω-3) and safflower oil (rich in ω-6), we studied the generation of bioactive metabolites, such as eicosanoids and free radicals generated via lipid peroxidation. In addition, we determined the effect of PUFAs on several inflammatory and fibrotic factors, e.g. gene as well as protein expression, using western blot and RT-PCR, respectively. We also investigated the effect of PUFA diets on novel targets, such as hepatic membrane transporters with potential role in liver inflammation. Our results suggest that ω-3 diet prevented while ω-6 based diets promoted the development of fatty liver and inflammation. ω-3 PUFA reduced AA-peroxidation by lowering hepatic AA concentration and expression of peroxidation enzymes, COX-2 and 5-LOX, resulting in lower generation of pro-inflammatory AA-derived PGs (Series-2), HETEs and free radicals, along with increase in anti-inflammatory EPA and DHA-derived PGs (Series-3). ω-3 diet might also reduce liver inflammation by preventing activation of NF-кB and induction of TNF-α. Rats fed with ω-3 diet showed high protein expression of efflux transporters, MRP-2 and ABCA1, indicating elimination of peroxidation metabolites and triglycerides from the liver and decreased inflammation. In contrast, ω-6 diets led to increase in AA-peroxidation and generation of AA-derived pro-inflammatory metabolites. ω-6 based diets also promoted fatty liver and inflammation by activating NF-кB, inducing TNF-α and downregulation of efflux transporters, MRP-2 and ABCA1. This study not only provides new insights into the effects and possible mechanisms by which ω-3 and ω-6 PUFAs may alter hepatic steatosis and inflammation, but also put forward new targets of research, such as hepatic membrane transporters in relation to liver pathology in ALD.
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Evaluation of bone biochemical markers and inflammatory markers in yearlings fed varying ratios of omega-6 and omega-3 polyunsaturated fatty acidsRoss, Trinette Noel 15 May 2009 (has links)
Diets formulated to contain varying ratios of omega 6 to omega 3 fatty acids were
fed to exercising yearlings to evaluate bone activity and inflammatory response. Nine
Quarter Horse yearlings were arranged within a triplicated 3 X 3 Latin Square
experimental design and fed one of three diets. Exercise protocol was designed to
stimulate sub-clinical inflammation and normal bone response.
Body weight and physical growth measurements were not different between
groups (P > 0.05), and feed intake was similar between groups (P > 0.05).
Horses consuming soybean oil (SBO) diet had lower fatty acid profiles (% by
weight) of C16:0 and C16:1 (P < 0.05) when compared to horses consuming either corn
oil (CO) or menhaden/corn oil (MCO) diets. Though numerically different, percentage
changes in C16:0 and C16:1 were not different between diets (P < 0.05). Horses
consuming MCO had significantly higher measurements of C20:4, C20:5 and C22:6 over
the 28 day period when compared to horses consuming SBO or CO. Percent change in
mean concentrations of C20:5 were significantly different between the MCO group and the SBO group (P < 0.05) with no observed difference between MCO and CO treatment
groups.
Overall mean carboxyterminal telopeptide of type I collagen (ICTP)
concentrations did not differ between diets (P > 0.05) nor was there a significant change
from baseline values when compared to day 28 of the period.
Mean Osteocalcin (OC) concentrations did not differ between treatments (P >
0.05). Numerically, OC levels were lower after 14 days, with subsequent increases
occurring from day 14 to day 28; however, there was no significant day effect (P > 0.05).
Mean measurements of PGE2 and fibrinogen, the two inflammation markers
evaluated, did not differ among groups (P > 0.05). However, when fibrinogen data were
normalized, horses consuming SBO had a significantly lower change in baseline values
of fibrinogen compared to horses fed CO or MCO diets (P< 0.05).
In general, horses fed SBO exhibited reduced levels of the inflammatory marker
fibrinogen (P< 0.05). No other variable evaluated was influenced by the supplementation
of varying ratios of polyunsaturated fatty acids into the equine diet.
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Investigations into the epidemiology and aetiology of cancers of the skinWallingford, Sarah January 2014 (has links)
The cancers of the skin, melanoma and the keratinocyte cancers, basal cell andsquamous cell carcinomas (BCC and SCC), are among the most common cancersin white populations. While ultraviolet radiation (UVR) is their principal cause,links with non-UVR-related factors have also been noted. Ultimately, theinteraction of these elements results in malignancy however, understanding oftheir specific contributions remains incomplete. This thesis reports findings fromsix studies aiming to investigate gaps in current knowledge of the role of UVR andnon-UVR-related risk factors on skin cancer. The papers are groupedaccording to the aspects of skin cancer epidemiology and aetiology they address. The first two papers address the descriptive epidemiology of melanoma inEngland, a country with low ambient solar UVR. They arise from ecologicalstudies using national melanoma registration data and document rising trends inmelanoma incidence by anatomic site (Paper 1), and by region of residence andsocio-economic deprivation (Paper 2). Their findings were consistent with thesuggestion that increases in recreational UVR exposure are driving rises inmelanoma rates. These results emphasise both the need to closely monitor UVRexposure and melanoma trends and the importance of public health campaigns. The second group of three papers considers the assessment of associations ofnutritional factors with keratinocyte cancer. Two studies use data from aprospective cohort to evaluate the relationship between dietary intake (Paper 3)and blood concentrations (Paper 4) of omega-3 and omega-6 polyunsaturatedfatty acids (PUFA) in relation to BCC and SCC risk. Associations with both PUFAtypes were observed. In addition, Paper 5, a three-way correlational assessment,demonstrated that questionnaire and blood circulating levels of omega-3 PUFAwere highly correlated with measures of skin bioavailability. Collectively, thesestudies give evidence for associations of these nutrients with skin cancer and forthe utility of both intake and biomarker measures for assessing the relationships. The final paper explores the relationship between a widely cited non-UVR riskfactor, namely scars and cancers of the skin. It reports a systematic review of allpublished observational studies quantifying this association. While innumerablecase reports were found, quantitative analyses were rare. The review identifieda major gap in the literature where knowledge of scar malignancies is notevidence-based, but rather founded mainly on cumulative anecdotal reporting. Taken together, this body of published work highlights the largely unrecognisedcomplexity of the aetiology of cancers of the skin. Future research must bebroad in scope in order to advance understanding of the interaction betweenUVR and other risk factors and to provide a base for health messages aimed atreducing the burden of these malignancies.
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Dietary Chemoprevention Studies in Preclinical Models of Prostate Cancer: Bioactive Lipids and Vitamin DSmolinski, Justin Bruce 26 October 2010 (has links)
No description available.
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Stanovení hladin mastných kyselin v tkáních zdravých, náhle zemřelých a polymorbidních pacientů / The determination of fatty acid levels in the tissues of healthy, suddenly deceased persons and polymorbid patientsNovotná, Monika January 2019 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Candidate: Monika Novotná Supervisor of Diploma Thesis: Mgr. Monika Kuchařová, Ph.D. Title of Diploma Thesis: The determination of fatty acid levels in the tissues of healthy, suddenly deceased persons and polymorbid patients The aim of the thesis was to determine the levels of 14 fatty acids in tissues of suddenly deceased, otherwise healthy individuals and in the group of polymorbid, chronic patients. It was a comparison of fatty acid levels in seven tissues of the human body: subendocardial left ventricular tissue, liver parenchyma tissue, kidney cortex, adrenal tissue, skeletal muscle, abdominal subcutaneous adipose tissue, and brain tissue. Each group included 10 deceased patients. The theoretical part incudes fatty acids as the main component of lipids. It deals mainly with the group of polyunsaturated fatty acids and their relation to pathologies in the human body. Gas chromatography, thanks to which we analyzed the fatty acid spectrum, is also described. The experimental part consists of the basic characteristics of the research groups, the description of the workflow and the results. Statistically processed data are divided into categories by individual fatty acids and other monitored...
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Óleo de linhaça na dieta de frangos de corteLopes, Débora Cristina Nichelle 22 March 2012 (has links)
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Previous issue date: 2012-03-22 / A trial was conducted to evaluate the effects of replacing soybean oil by linseed oil on performance, carcass traits, physicochemical characteristics, sensory properties of meat and plasma biochemical profile of poultry. A total of 448 one day old male birds (Cobb 500) where randomly allotted to 4 treatments and 8 replications in a completely randomized assay for 35 days. The following treatments were tested: T1
= 100% soybean oil (SO) as the main dietary energy source; T2 = 50% SO and 50% linseed oil (LO); T3 = 25% SO and 75% LO; and T4 = 100% LO. Performance of birds was not affected (P>0.05) when LO replaced SO in the diets during the whole
experimental period. Additionally, no significant difference (P>0.05) was observed in carcass traits of birds fed diets containing LO. Moreover, plasma biochemical profile was not affected (P>0.05) as the level of LO increased in the diets. Omega-3 fatty acids (n3-PUFA) increased in the meat, omega-6 fatty acids (n6-PUFA) and meat n6:n3 decreased as the dietary level of LO was increased. Reduction of drumstick fat
was observed increasing levels of LO in the diet (P<0,05). No significant differences (P>0.05) were observed for dry matter, protein, fat and cholesterol in the meat. Also, no significant differences (P>0.05) were found for physicochemical characteristics and sensory properties of meat. Replacing SO by LO in the diet might be carried out with no effect on performance, carcass traits and biochemical profile of poultry.
Dietary LO enriched poultry meat with C18:3n3, C20:3n3 e C20:5n3 and reduced n6:n3 ratio without any negative effects on chemical composition and physicochemical characteristics and sensory properties of meat. / O presente estudo foi realizado com o objetivo de avaliar os efeitos da substituição do óleo de soja pelo óleo de linhaça sobre o desempenho produtivo, características de carcaça, características químicas, instrumentais, sensoriais e perfil de ácidos graxos da carne além do perfil bioquímico sérico de frangos de corte. Utilizou-se 448 frangos da linhagem Cobb 500, machos, de um dia de idade, distribuídos em 4 tratamentos, com 8 repetições, em um delineamento completamente casualizado, por um período de 35 dias. Os tratamentos utilizados foram: T1 = 100% de óleo de soja
(OS) como principal fonte energética; T2 = 50% de OS e 50% de óleo de linhaça (OL); T3 = 25% de OS e 75% de OL; e T4 = 100% de OL. A substituição do OS pelo OL na dieta não afetou (P>0,05) o desempenho produtivo dos frangos durante todo
o período experimental. Também não foram observadas diferenças significativas (P>0,05) sobre as características de carcaça das aves que receberam OL na dieta. Da mesma forma, os níveis plasmáticos dos frangos não diferiram significativamente (P>0,05) com o aumento de óleo de linhaça na dieta. O aumento do OL na dieta promoveu o incremento de ácidos graxos da família ômega-3 (3n-AGPI), a redução
de ácidos graxos da família ômega-6 (6n-AGPI) e da relação 6n-AGPI:3n-AGPI na carne. Houve redução no teor de gordura da sobrecoxa com o aumento de OL na dieta (P<0,05). Não foram observadas diferenças significativas (P>0,05) no percentual de matéria seca, proteína, gordura e colesterol na carne. Também não foram observadas diferenças significativas (P>0,05) sobre as características físicoquímicas e sensoriais da carne. A substituição do OS pelo OL na dieta de frangos de
corte pode ser realizada sem afetar o desempenho produtivo, características de carcaça e perfil bioquímico. O OL na dieta de frangos de corte promoveu o enriquecimento da carne com C18:3n3, C20:3n3 e C20:5n3 e a redução na relação 6n-
AGPI:3n-AGPI, sem afetar a composição química e as características físicoquímicas e sensoriais da carne.
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Stanovení mastných kyselin v lidských tkáních / Determination of fatty acids in human tissuesTurňová, 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...
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Stanovení spektra mastných kyselin u pacientů podstupujících léčbu taxany / Determination of the fatty acids spectrum in patients undergoing treatment with taxanesKuříková, 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...
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