800 resultados para Volatile Fatty-acids
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Most meningiomas are benign tumours of arachnoidal origin, although a small number have high proliferative rates and invasive properties which complicate complete surgical resection and are associated with increased recurrence rates. Few prognostic indicators exist for meningiomas and further research is necessary to identify factors that influence tumour invasion, oedema and recurrence. Paraffin sections from 25 intracranial meningiomas were analysed for expression of the proteins vascular endothelial growth factor (VEGF), VEGF receptors Flt1 and Flk1, E-cadherin, metalloproteinases 2 and 9 (MMP2, MMP9), CD44, receptor for hyaluronic acid-mediated motility (RHAMM), hyaluronic acid (HA), CD45, cyclooxygenase 2 (COX2), brain fatty acid binding protein (BFABP), Ki67, and proliferating cell nuclear antigen (PCNA). Correlations among protein expression were found for several markers of proliferation (Ki67, PCNA, MI) and microvessel density (MVD). COX2 expression increased with increasing with tumour grade and correlated with Ki67, PCNA, MI, MVD, and BFABP. BFABP expression also correlated with Ki67 and PCNA expression. Relationships were also identified among angiogenic factors (VEGF, Flt1, Flk1) and proliferation markers. Oedema was found to correlate with MMP9 expression and MMP9 also correlated with proliferation markers. No correlations were found for MMP2, E-cadherin, or CD44 in meningiomas. In conclusion Ki67, PCNA, MI, MVD, BFABP, and COX2 were significantly correlated with meningioma tumour grade and with each other. These findings, by correlating both intracellular fatty acid transport and eicosanoid metabolism with tumour proliferation, as determined by Ki67 labelling and mitotic index, suggest fatty acids are involved in the progression of meningiomas.
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Epilepsy is the most common neurological disorder in both dogs and humans. Although the pharmacological options for treatment of epilepsies have increased. it has been reported that two-thirds of dogs with epilepsy are refractory to antiepileptic drug therapy. To our knowledge, there are no experimental Studies in the literature that show an effect of omega-3 supplementation oil epilepsy in dogs. Our case study describes the effectiveness of daily intake of a moderate amount of fish oil in a case of canine epilepsy. (C) 2009 Elsevier Inc. All rights reserved.
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The effects of type of grain (wheat vs. sorghum) and oil supplement/kg diet [0, 20g olive oil (OL), 20g safflower oil (SO), 10 g OL plus 10 g SO (OLSO)], over a 12-week period on the performance, plasma and lipoproteins lipids [cholesterol (C), triglycerides (TG), phospholipid (P)], and yolk C and fatty acids concentrations of laying hens were studied. Hens fed on the sorghum diet had significantly (P
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The dissected carcass composition and fatty acid profiles of intermuscular fat from 110 male goat kids from six genotypes i.e. Boer x Angora (BA), Boer x Feral (BF), Boer x Saanen (BS), Feral x Feral (1717), Saanen x Angora (SA) and Saanen x Feral (SF) and two slaughter weight groups i.e. Capretto and Chevon (liveweight at slaughter 14-22 and 30-35 kg, respectively) were compared. Carcass tissue distribution for various genotypes was: muscle (63-66%), fat (10-13%) and bone (21-24%). Genotype significantly (P < 0.05) influenced the carcass composition; BA and FF carcasses had significantly higher muscle to bone ratio, while carcasses from BS kids were leaner compared to other genotypes. However, the two slaughter weight groups did not differ significantly (P > 0.05) in terms of carcass composition, when compared at the same carcass weight. In the present study, significant (P < 0.01) correlations were observed between percentage of muscle, fat and bone in most of the primal cuts and that in the carcass side. The main saturated fatty acids (SFAs) identified were palmitic (16:0) and stearic acid (18:0), while oleic acid (18: 1, omega9) was the main unsaturated fatty acid (UFA) in the intermuscular fat from goat kids. There were significant (P < 0.05) differences between genotypes in the proportions of individual fatty acids. Adipose tissue from BS kids had significantly higher UFAs (mainly oleic acid) and thus had a significantly lower melting point compared to other genotypes. There were significantly higher proportions of palmitic acid (35%) in the adipose tissue from Capretto kids compared to that from Chevon kids (22%). The concentration of UFAs increased in the adipose tissue from Capretto to Chevon carcasses. (C) 2003 Elsevier Science B.V. All rights reserved.
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Biodiesel is the main alternative to fossil diesel and it may be produced from different feedstocks such as semi-refined vegetable oils, waste frying oils or animal fats. However, these feedstocks usually contain significant amounts of free fatty acids (FFA) that make them inadequate for the direct base catalyzed transesterification reaction (where the FFA content should be lower than 4%). The present work describes a possible method for the pre-treatment of oils with a high content of FFA (20 to 50%) by esterification with glycerol. In order to reduce the FFA content, the reaction between these FFA and an esterification agent is carried out before the transesterification reaction. The reaction kinetics was studied in terms of its main factors such astemperature, % of glycerin excess, % of catalyst used, stirring velocity and type of catalyst used. The results showed that glycerolysis is a promising pretreatment to acidic oils or fats (> 20%) as they led to the production of an intermediary material with a low content of FFA that can be used directly in thetransesterification reaction for the production of biodiesel. (C) 2011 Elsevier B.V. All rights reserved.
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OBJECTIVE: To analyze the monounsaturated and polyunsaturated trans fatty acid intake among the general population. METHODS: A cross-sectional study was conducted in São Paulo, Southeastern Brazil, in 2003, on a representative sample of 2,298 male and female subjects, including 803 adolescents (12 to 19 years), 713 adults (20 to 59 years) and 782 elderly people (60 years or over). Food intake was measured using 24-hour recall. Mean trans fatty acid intake was described according to gender and age group. RESULTS: The mean trans fatty acid intake was 5.0 g/day (SE = 0.1), accounting for 2.4% (SE = 0.1) of total energy and 6.8% (SE = 0.1) of total lipids. The adolescents had the highest mean intake levels (7.4 g/day; 2.9% of energy) while the adults and the elderly had similar intake (2.2% of energy for both; 6.4% of lipids and 6.5% of lipids, respectively). The mean trans fatty acid intake among adult and elderly women (approximately 2.5% of energy and 7.0% of lipids) was higher than among men in the same age group. The food item with the highest contribution towards trans fatty acids was margarine, accounting for more than 30% of total intake, followed by filled cookies among adolescents and meat among adults and the elderly. CONCLUSIONS: The trans fatty acid intake is above the level recommended by the World Health Organization. Replacement of the trans fatty acids in manufactured food items may be an effective measure for reducing trans fatty acid intake in Brazil.
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INTRODUCTION: Fatty acids are abundant in vegetable oils. They are known to have antibacterial and antifungal properties. METHODS: Antifungal susceptibility was evaluated by broth microdilution assay following CLSI (formerly the NCCLS) guidelines against 16 fungal strains of clinical interest. RESULTS: In this work, fatty acid methyl esters (FAME) was able to inhibit 12 clinical strains of the pathogenic fungus Paracoccidioides brasiliensis and were also active in the bioautographic assay against Cladosporium sphaerospermum. CONCLUSIONS: FAME was a more potent antifungal than trimethoprim-sulfamethoxazole against P. brasiliensis under the experimental conditions tested.
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Tese de Doutoramento em Ciências - Especialidade em Biologia
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Tese de Doutoramento em Biologia Ambiental e Molecular
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The nutritional composition o f orange roughy (collected from the Northeast Atlantic near the Rockall Trough) was studied on a seasonal basis. In addition samples were aged and stability assessed. Protein levels (16.68-16.21% w/w) were found to be slightly higher than those recorded for the N ew Zealand species o f orange roughy and compared favourably with protein values for fish muscle in general. Statistically results show a significant seasonal variation with no variation from fish to fish or in the location within the fish. Lipid content (3.6-4.5% w/w) was found to be much lower than that recorded for New Zealand. As with protein statistically results show a significant seasonal variation and no variation from fish to fish or in the location within the fish. Moisture levels (77.3_79.6%w/w) compared favourably with values obtained from other studies. Again statistically results show a significant seasonal variation with no variation from fish to fish or within the fish. Iodine values (74.63-79.54) indicate the likely presence o f a high level o f mono unsaturated fatty acids. Statistically results show no significant seasonal variation and no sample variation or variation within fish. Thin layer chromatography o f the extracted fat showed the major type to be wax esters with a much lower amount o f triglycerides and smaller amounts of polar lipids, free sterols and free fatty acids. Total fatty acid composition was found to be very similar to that recorded from other studies and showed that most o f the oils extracted from the fish muscle contained a high percentage o f mono unsaturates namely 16:1,18:1, 20:1 and 22:1 (85.63 - 91.14% ) with 16:1 present in the smallest amounts and 18:1 the major one. The only saturated fatty M.Sc. in Biochemistry III Nutritional Composition, Quality and Spoilage Capacity of Specific Deep Sea Fish acids present in significant quantities were 14:0, 16:0 and 18:0, the total varied from a seasonal average high o f 4.05 % to an average low o f 2.27%. The polyunsaturated fatty acids linoleic and arachidonic acid were present in small quantities varying in total from 0.89% to 1.50%. Docosapentaenoic acid (D P A ) was found only in trace quantities in spring, autumn and winter samples and undetected in summer. Levels o f Eicosapentaenoic acid (EPA ) and Docosahexaenoic acid (D H A ) were also found in very low percentages and varied on a seasonal basis with average values ranging from 0.41% in summer to 1.03 % in autumn for EPA and from 1.44 % in summer to3.20 % in autumn for D H A . Again statistically results show a significant seasonal variation with no variation from fish to fish or location within the fish. Levels o f freshness were measured using the Thiobarbituric acid (T B A ), Total volatile base nitrogen (T V B -N ) and Trimethylamine (T M A ) techniques. The quality o f the fish upon arrival was excellent and well below legal/acceptable lim its.T V B -N values ranged from 6.88-8.91 mg/lOOg and T M A values from 4.82-6.46 mg/lOOg Values for T B A ranged from 0.18-0.35 mg Malonaldehyde/kg fish. The summer values were higher than the other seasons. Seasonal variation was significant for all methods with no variation from fish to fish or within the fish. Fish aged at +4°C in air did not exceed the T V B N lim it o f 35mg/100g until day 6 whereas the T V B N lim it was extended to 8 days for fish aged at +4°C in vacuum. However the T M A lim it o f 12mg/100g was reached on day 4 for fish stored at +4°C in air and on day 5 for vacuum packed samples stored at +4°C . Fish stored at -5°C in air and vacuum packed did not reach the T V B N lim it until day 61 but the T M A limit was reached on day 24 for fish stored at -5°C in air and was extended to 31 days for vacuum packed fish stored at-5°C. Prolonged storage at -18°C caused some deterioration o f the frozen fish muscle. Upon thawing the shelf life o f fish stored for 12 months was much shorter than that stored for 6 M.Sc. in Biochemistry IV Nutritional Composition, Quality and Spoilage Capacity of Specific Deep Sea Fish months. This in turn deteriorated faster than fresh fish held at refridgeration temperature in air. Orange roughy were found to be a good source of protein with moisture levels similar to that o f other fish. They were o f medium fat content but have a very poor content o f the essential omega 3 and omega 6 fatty acids. Orange roughy can be stored at -18°C but its subsequent refridgerated shelf life will be shorter than that o f unfrozen orange roughy stored at refridgeration temperature. Orange roughy are a very important part o f the ecosystem. Their composition is less nutritionally beneficial than more readily available fish for human consumption and therefore should not be fished at all
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Background: Several studies have demonstrated clinical benefits of fish consumption for the cardiovascular system. These effects are attributed to the increased amounts of polyunsaturated fatty acids in these foods. However, the concentrations of fatty acids may vary according to region. Objective: The goal of this study was to determine the amount of,cholesterol and fatty acids in 10 Brazilian fishes and in a non-native farmed salmon usually consumed in Brazil. Methods: The concentrations of cholesterol and fatty acids, especially omega-3, were determined in grilled fishes. Each fish sample was divided in 3 sub-samples (chops) and each one was extracted from the fish to minimize possible differences in muscle and fat contents. Results: The largest cholesterol amount was found in white grouper (107.6 mg/100 g of fish) and the smallest in badejo (70 mg/100 g). Omega-3 amount varied from 0.01 g/100 g in badejo to 0.900 g/100 g in weakfish. Saturated fat varied from 0.687 g/100 g in seabass to 4.530 g/100 g in filhote. The salmon had the greatest concentration of polyunsaturated fats (3.29 g/100 g) and the highest content of monounsaturated was found in pescadinha (5.98 g/100 g). Whiting and boyfriend had the best omega-6/omega 3 ratios respectively 2.22 and 1.19, however these species showed very little amounts of omega-3. Conclusion: All studied Brazilian fishes and imported salmon have low amounts of saturated fat and most of them also have low amounts of omega-3.
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Polyhydroxyalkanoate (PHA) is a family of polymers composed primarily of R-3-hydroxyalkanoic acids. These polymers have properties of biodegradable thermoplastics and elastomers. Medium-chain-length PHAs (MCL-PHAs) are synthesized in bacteria by using intermediates of the beta-oxidation of alkanoic acids. To assess the feasibility of producing MCL-PHAs in plants, Arabidopsis thaliana was transformed with the PhaC1 synthase from Pseudomonas aeruginosa modified for peroxisome targeting by addition of the carboxyl 34 amino acids from the Brassica napus isocitrate lyase. Immunocytochemistry demonstrated that the modified PHA synthase was appropriately targeted to leaf-type peroxisomes in light-grown plants and glyoxysomes in dark-grown plants. Plants expressing the PHA synthase accumulated electron-lucent inclusions in the glyoxysomes and leaf-type peroxisomes, as well as in the vacuole. These inclusions were similar to bacterial PHA inclusions. Analysis of plant extracts by GC and mass spectrometry demonstrated the presence of MCL-PHA in transgenic plants to approximately 4 mg per g of dry weight. The plant PHA contained saturated and unsaturated 3-hydroxyalkanoic acids ranging from six to 16 carbons with 41% of the monomers being 3-hydroxyoctanoic acid and 3-hydroxyoctenoic acid. These results indicate that the beta-oxidation of plant fatty acids can generate a broad range of R-3-hydroxyacyl-CoA intermediates that can be used to synthesize MCL-PHAs.
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Amino acids have been reported to increase endogenous glucose production in normal human subjects during hyperinsulinemia: however, controversy exists as to whether insulin-mediated glucose disposal is inhibited under these conditions. The effect of an amino acid infusion on glucose oxidation rate has so far not been determined. Substrate oxidation rates, endogenous glucose production, and [13C]glucose synthesis from [13C]bicarbonate were measured in six normal human subjects during sequential infusions of exogenous glucose and exogenous glucose with (n = 5) or without (n = 5) exogenous amino acids. Amino acids increased endogenous glucose production by 84% and [13C]glucose synthesis by 235%. Glucose oxidation estimated from indirect calorimetry decreased slightly after amino acids, but glucose oxidation estimated from [13C]glucose-13CO2 data was increased by 14%. It is concluded that gluconeogenesis is the major pathway of amino acid degradation. During amino acid administration, indirect calorimetry underestimates the true rate of glucose oxidation, whereas glucose oxidation calculated from the 13C enrichment of expired CO2 during [U-13C]glucose infusion does not. A slight stimulation of glucose oxidation during amino acid infusion, concomitant with an increased plasma insulin concentration, indicates that amino acids do not inhibit glucose oxidation.
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Many organisms use fatty acid derivatives as biological regulators. In plants, for example, fatty acid-derived signals have established roles in the regulation of developmental and defense gene expression. Growing numbers of these compounds, mostly derived from fatty acid hydroperoxides, are being characterized. The model plant Arabidopsis thaliana is serving a vital role in the discovery of fatty acid-derived signal molecules and the genetic analysis of their synthesis and action. The Arabidopsis genome sequencing project, the availability of large numbers of mutants in fatty acid biosynthesis and signal transduction, as well as excellent pathosystems, make this plant a tremendously useful model for research in fatty acid signaling. This review summarizes recent progress in understanding fatty acid signaling in A. thaliana and highlights areas of research where progress is rapid. Particular attention is paid to the growing literature on the jasmonate family of regulators and their role in defense against insects and microbial pathogens.
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Liver fatty-acid-binding protein (L-FABP) is a cytoplasmic polypeptide that binds with strong affinity especially to long-chain fatty acids (LCFAs). It is highly expressed in both the liver and small intestine, where it is thought to have an essential role in the control of the cellular fatty acid (FA) flux. Because expression of the gene encoding L-FABP is increased by both fibrate hypolipidaemic drugs and LCFAs, it seems to be under the control of transcription factors, termed peroxisome-proliferator-activated receptors (PPARs), activated by fibrate or FAs. However, the precise molecular mechanism by which these regulations take place remain to be fully substantiated. Using transfection assays, we found that the different PPAR subtypes (alpha, gamma and delta) are able to mediate the up-regulation by FAs of the gene encoding L-FABP in vitro. Through analysis of LCFA- and fibrate-mediated effects on L-FABP mRNA levels in wild-type and PPARalpha-null mice, we have found that PPARalpha in the intestine does not constitute a dominant regulator of L-FABP gene expression, in contrast with what is known in the liver. Only the PPARdelta/alpha agonist GW2433 is able to up-regulate the gene encoding L-FABP in the intestine of PPARalpha-null mice. These findings demonstrate that PPARdelta can act as a fibrate/FA-activated receptor in tissues in which it is highly expressed and that L-FABP is a PPARdelta target gene in the small intestine. We propose that PPARdelta contributes to metabolic adaptation of the small intestine to changes in the lipid content of the diet.