Colon cancer is one of the most commonly diagnosed cancers in the US, yet small intestine cancer is a rare event. While there are many similarities between these two tissues, inherent differences such as redox status, may contribute to the variation in cancer occurrence. We examined the difference in reactive oxygen species (ROS) generation, antioxidant enzyme activity and oxidative DNA damage in the small and large intestine of rats under normal conditions and following exposure to exogenous oxidative stress. Basal ROS and antioxidant enzyme activities were greater in the colon than the small intestine, and the balance of ROS to antioxidant enzymes in the colon was more pro-oxidant than in the small intestine. During oxidative stress, ROS and oxidative DNA damage were greater in the colon than the small intestine. Thus the colon responds to oxidative stress less effectively than the small intestine, possibly contributing to increased cancer incidence at this site. We next wanted to understand how diets containing a combination of fish or corn oil and pectin or cellulose may alter the redox environment of the colon. ROS, oxidative DNA damage, antioxidant enzyme activity and apoptosis were measured in colonocytes of rats fed one of four diets containing either corn oil or fish oil and cellulose or pectin. Measurements were madein rats untreated with carcinogen and rats exposed to a chemical carcinogen and radiation. In rats not treated with a carcinogen, fish oil enhanced ROS, and fish oil/pectin suppressed antioxidant enzymes as compared to corn oil/cellulose. Oxidative DNA damage was inversely related to ROS in the fish oil/pectin diet and apoptosis was enhanced relative to other diets. In carcinogen treated and irradiated rats, a similar protective effect was seen with fish oil/pectin as evidenced by a reduction in oxidative DNA damage and enhancement of apoptosis. This suggests that a diet containing fish oil/pectin may protect against colon carcinogenesis by modulation of the redox environment to promote apoptosis and minimize oxidative DNA damage.

Peptides have assumed considerable importance in pharmaceutical industry and vaccine research. Understanding the structural features of these peptide molecules can be effective not only in mimicking natural proteins but also in the design of new biomaterials. Polypeptide sequences consisting of twenty genetically coded amino acids possess structural flexibility, which makes the predictions difficult. However, the introduction of non-protein amino acids into the peptide chain restricts the available range of backbone conformations and acts as stereochemical directors of polypeptide chain folding. Such conformationally rigid residues allow the formation of well defined structures like helices, strands etc, which further assemble into super secondary structural motifs by flexible linkages. Crystal structure determination of the oligopeptides by X-ray diffraction gives insight into the specific conformational states, modes of aggregation, hydrogen bond interactions, solvation of peptides and various weakly polar interactions involving the side chains of aromatic residues (Phe, Trp and Tyr). In β-, γ- and higher ω-amino acids, due to the insertion of one or more methylene groups between the N- and Cα-atoms into the peptide backbone the accessible conformational space is greater than the α-amino acids. The β-, γ-, δ-…. amino acid residues belong to the family of ω-amino acids. Extensive research in the field of β-peptides, which have been experimentally verified or theoretically postulated, has assigned several helices, turns and sheets. The use of ω-amino acid residues in conjunction with α-residues permits systematic exploration of the effects of introducing additional backbone atoms into well-characterized α-peptide structures. The observation of new families of hydrogen bonded motifs in the hybrid peptides containing α- and ω-amino acids are the recent interest in this regard. This thesis reports results of X-ray crystallographic studies of eighteen designed peptides and four protected ω-amino acids listed below. Within brackets are given the abbreviations used for the sequences (Symbol U represents Aib). The ω-amino acids reported in this thesis are: (S)-β3-HAla (β3-homoalanine), (R)-β3-HVal, (S)-β3-HVal (β3-homovaline), (S)-β3-HPhe (β3-homophenylalanine), (S)-β3-HPro (β3-homoproline), βGly (β-homoglycine), γAbu (gamma aminobutyric acid) and δAva (delta aminovaleric acid). 1. Boc-Leu-Trp-Val-OMe (LWV), C28H42N4O6 2. Ac-Leu-Trp-Val-OMe (Space group P21) (LWV1), C25H36N4O5 3. Ac-Leu-Trp-Val-OMe (Space group P212121) (LWV2), C25H36N4O5 4. Boc-Leu-Phe-Val-OMe (LFV), C26H41N3O6 5. Ac-Leu-Phe-Val-OMe (LFV1), C23H35N3O5 6. Boc-Ala-Aib-Leu-Trp-Val-OMe (AULWV), C35H54N6O8 7. Boc-Trp-Trp-OMe (WW), C28H32N4O5 8. Boc-Trp-Aib-Gly-Trp-OMe. (WUGW), C34H42N6O7 9. Boc-Leu-Trp-Val-Ala-Aib-Leu-Trp-Val-OMe (H8AU), C57H84N10O11 10. Boc-(S)-β3-HAla-NHMe (BANH), C10H20N2O3 11. Boc-(R)-β3-HVal-NHMe (BVNH), C12H24N2O3 12. Boc-(S)-β3-HPhe-NHMe (BFNH), C16H24N2O3 13. Boc-(R)-β3-HVal-(R)-β3-HVal-OMe (BVBV), C18H34N2O5 14. Boc-(R)-β3-HVal-(S)-β3-HVal-OMe (LVDV), C18H34N2O5 15. Boc-(S)-β3-HPro-OH (BPOH), C11H19N1O4 16. Boc-Leu-Phe-Val-Aib-(S)-β3-HPhe-Leu-Phe-Val-OMe (UBF8), C60H88N8O11 17. Piv-Pro-Gly-NHMe (PA1), C13H23N3O3 18. Piv-Pro-βGly-NHMe (PB1), C14H25N3O3 19. Piv-Pro-βGly-OMe (PBO), C14H24N2O4 20. Piv-Pro-δAva-OMe (PDAVA), C16H28N2O4 21. Boc-Pro-γAbu-OH (BGABU), C14H24N2O5 22. Boc-Aib-γAbu-OH (UG), C13H24N2O5 23. Boc-Aib-γAbu-Aib-OMe (UGU), C18H33N3O6 The thesis is divided into seven chapters. Chapter 1 gives a general introduction to the stereochemistry of polypeptide chains and the secondary structure classification: helices, β-sheets and β-turns followed by an overview of different types of weakly polar interactions involving the side chains of aromatic amino acid residues. This section also provides a brief overview of the conformational analysis of β-, γ- and higher ω-amino acid residues in oligomeric β-peptides and in α,ω-hybrid peptides. A brief discussion on X-ray diffraction and solution to the phase problem is also presented. Chapter 2 describes the crystal structures of the peptides, Boc-Leu-Trp-Val-OMe (LWV), the two polymorphs of Ac-Leu-Trp-Val-OMe (LWV1 and LWV2), Boc-Leu-Phe-Val-OMe (LFV), Ac-Leu-Phe-Val-OMe (LFV1) and Boc-Ala-Aib-Leu-Trp-Val-OMe (AULWV), in order to explore the nature of interactions between aromatic rings, specifically the indole side chain of Trp residues [1]. Peptide LWV adopts a type I β-turn conformation, stabilized by an intramolecular 4→1 hydrogen bond. Molecules of LWV pack into helical columns stabilized by two intermolecular hydrogen bonds, Leu(1)NH…O=CTrp(2) and Indole NH…O=CLeu(1). The superhelical columns further pack into the tetragonal space group P43 by means of a continuous network of indole - indole interactions. The peptide Ac-Leu-Trp-Val-OMe crystallized in two polymorphic forms: P21 (LWV1) and P212121 (LWV2). In both forms, the peptide backbone is extended and the crystal packing shows anti-parallel β-sheet arrangement. Similarly, extended strand conformation and anti-parallel β-sheet formation are also observed in the Phe containing analogs, LFV and LFV1. The pentapeptide AULWV adopts a short stretch of 310-helix. Analysis of aromatic - aromatic and aromatic - amide interactions in the structures of peptides LWV, LWV1 and LWV2 are reported along with the examples of 12 Trp containing peptides from the Cambridge Structural Database. The results suggest that there is no dramatic preference for the orientation of two proximal indole rings. In Trp containing peptides specific orientations of the indole ring, with respect to the preceding and succeeding peptide units, appear to be preferred in β-turns and extended structures. Crystal parameters LWV: C28H42N4O6; P43; a = 14.698(1) Å, b = 14.698(1) Å, c = 13.975(2) Å; Z = 4; R = 0.0737, wR2 = 0.1641. LWV1: C25H36N4O5; P21; a =10.966(3) Å, b = 9.509(2) Å; c = 14.130(3) Å, β = 104.94(1)°; Z = 2; R = 0.0650, wR2 = 0.1821. LWV2: C25H36N4O5; P212121; a = 9.533(6) Å, b = 14.148(9) Å, c = 19.53(1) Å, Z = 4; R = 0.0480, wR2 = 0.1365. LFV: C26H41N3O6; C2; a = 31.318(8) Å, b = 10.022(3) Å, c = 9.657(3) Å, β = 107.41(1)°; Z = 4; R = 0.0536, wR2 = 0.1328. LFV1: C23H35N3O5; P212121; a = 9.514(8) Å, b = 13.56(1) Å, c = 20.04(2) Å, Z = 4; R = 0.0897, wR2 = 0.1960. AULWV: C35H54N6O8.2H2O; P21; a = 9.743(3) Å, b = 22.807(7) Å, c = 10.106(3) Å, β = 105.73(2)°; Z = 2; R = 0.0850; wR2 = 0.2061. Chapter 3 describes the crystal structures of three peptides containing Trp residues at both N- and C-termini of the peptide backbone: Boc-Trp-Trp-OMe (WW), Boc-Trp-Aib-Gly-Trp-OMe (WUGW) and Boc-Leu-Trp-Val-Ala-Aib-Leu-Trp-Val-OMe (H8AU). Peptide WW adopts an extended conformation and the molecules pack into an arrangement of parallel β-sheet in crystals, stabilized by three intermolecular N-H…O hydrogen bonds. The potential hydrogen bonding group NE1H of Trp(1), which does not take part in hydrogen bonding interaction with an oxygen acceptor participate in an intermolecular N-H…π interaction. Peptide WUGW adopts a folded structure, stabilized by a consecutive type II-I’ β-turn conformation. The crystal of WUGW contains a stoichiometric amount of chloroform in two distinct sites each with an occupancy factor of 0.5 and the structure provides examples of N-H…π, C-H…π, π…π, N-H…Cl, C-H…Cl and C-H…O interactions [2]. The molecular conformation of H8AU reveals a 310-helix. The crystal structure of H8AU reveals an interesting packing motif in which helical columns are stabilized by side chain - backbone hydrogen bond involving the indole NH of Trp(2) as donor and C=O group of Leu(6) as acceptor of a neighboring molecule, which closely resembles the hydrogen bonding pattern obtained in the tripeptide LWV [1]. Helical columns also associate laterally and strong interactions are observed between the Trp(2) and Trp(7) residues on neighboring molecules [3]. The edge-to-face aromatic interactions between the indoles suggest a potential C-H…π interaction involving the CE3H of Trp (2) Crystal parameters WW: C28H32N4O5; P212121; a = 5.146(1) Å, b = 14.039(2) Å, c = 35.960(5) Å; Z = 4; R = 0.0503, wR2 = 0.1243. WUGW: C34H42N6O7.CHCl3; P21; a = 12.951(5) Å, b = 11.368(4) Å, c = 14.800(5) Å, β = 101.41(2)°; Z = 2; R = 0.1095, wR2 = 0.2706. H8AU: C57H84N10O11; P1; a = 10.494(7) Å, b = 11.989(7) Å, c = 13.834(9) Å, α = 70.10(1)°, β = 82.74(1)°, γ = 78.96(1)°; Z = 1; R = 0.0855, wR2 = 0.1965. Chapter 4 describes the crystal structures of four protected β-amino acid residues, Boc-(S)-β3-HAla-NHMe (BANH); Boc-(R)-β3-HVal-NHMe (BVNH); Boc-(S)-β3-HPhe-NHMe (BFNH); Boc-(S)-β3-HPro-OH (BPOH) and two β-dipeptides, Boc-(R)-β3-HVal-(R)-β3-HVal-OMe (BVBV); Boc-(R)-β3-HVal-(S)-β3-HVal-OMe (LVDV). Gauche conformations about the Cβ-Cα bonds (θ ~ ± 60°) are observed for the β3-HPhe residue in BFNH and all four β3-HVal residues in the dipeptides BVBV and LVDV. Trans conformations (θ ~ 180°) are observed for β3-HAla residues in both independent molecules in BANH and for the β3-HVal and β3-HPro residues in BVNH and BPOH, respectively. In all these cases except for BPOH, molecules associate in the crystals via intermolecular backbone hydrogen bonds leading to the formation of sheets. The polar strands formed by β3-residues aggregate in both parallel (BANH, BFNH, LVDV) and anti-parallel (BVNH, BVBV) fashion. Sheet formation accommodates both the trans and gauche conformations about the Cβ - Cα bonds [4]. Crystal parameters BANH: C10H20N2O3; P1; a = 5.104(2) Å, b = 9.469(3) Å, c = 13.780(4) Å, α = 80.14(1)°, β = 86.04(1)°, γ = 89.93(1)°; Z =2; R = 0.0489, wR2 = 0.1347. BVNH: C12H24N2O3; P212121; a = 8.730(2) Å, b = 9.741(3) Å, c = 17.509(5) Å; Z = 4; R = 0.0479, wR2 = 0.1301. BFNH: C16H24N2O3; C2; a = 20.54(1) Å, b = 5.165(3) Å, c = 16.87(1) Å, β = 109.82(1)°; Z = 4; R = 0.0909, wR2 = 0.1912. BVBV: C18H34N2O5; P212121; a = 9.385(2) Å, b = 11.899(2) Å, c = 19.199(4) Å; Z = 4; R = 0.0583, wR2 = 0.1589. LVDV: C18H34N2O5; P212121; a = 5.170(4) Å, b = 10.860(8) Å, c = 37.30(3) Å; Z = 4; R = 0.0787, wR2 = 0.1588. BPOH: C11H19N1O4; P1; a = 5.989(2) Å, b = 6.651(2) Å, c = 8.661(3) Å, α = 70.75(1)°, β = 77.42(1)°, γ = 86.98(1)°; Z = 1; R = 0.0562, wR2 = 0.1605. Chapter 5 describes a new class of polypeptide helices in hybrid sequences containing α-, β- and γ-residues. The molecular conformation in crystals determined for the octapeptide Boc-Leu-Phe-Val-Aib-(S)-β3-HPhe-Leu-Phe-Val-OMe (UBF8) reveals an expanded helical turn in the hybrid sequence (ααβ)n. A repetitive helical structure composed of C14 hydrogen bonded units is observed. Using experimentally determined backbone torsion angles for the hydrogen bonded units formed by hybrid sequences, the energetically favorable hybrid helices have been generated. Conformational parameters are provided for C11, C12, C13, C14 and C15 helices in hybrid sequences [5]. Crystal parameters UBF8: C60H88N8O11; P212121; a = 12.365(1) Å, b = 18.940(2) Å, c = 27.123(3) Å; Z = 4; R = 0.0625, wR2 = 0.1274. Chapter 6 describes the crystal structures of five model peptides Piv-Pro-Gly-NHMe (PA1), Piv-Pro-βGly-NHMe (PB1), Piv-Pro-βGly-OMe (PBO), Piv-Pro-δAva-OMe (PDAVA) and Boc-Pro-γAbu-OH (BGABU). A comparison of the structures of peptides PA1 and PB1 illustrates the dramatic consequences upon backbone homologation in short sequences. The molecule PA1 adopts a type II β-turn conformation in the crystal state, while in PB1, the molecule adopts an open conformation with the β-residue being fully extended. The peptide PBO, which differs from PB1 by replacement of the C-terminal NH group by an O-atom, adopts an almost identical molecular conformation and packing arrangement in the crystal state. In peptide PDAVA, the observed conformation resembles that determined for PB1 and PBO, with the δAva residue being fully extended. In peptide BGABU, the molecule undergoes a chain reversal, revealing a β-turn mimetic structure stabilized by a C-H…O hydrogen bond [6]. Crystal parameters PA1: C13H23N3O3; P1; a = 5.843(1) Å, b = 7.966(2) Å, c = 9.173(2) Å, α = 114.83(1)°, β = 97.04(1)°, γ = 99.45(1)°; Z = 1; R = 0.0365, wR2 = 0.0979. PB1: C14H25N3O3.H2O; P212121; a = 6.297(3) Å, b = 11.589(5) Å, c = 22.503(9) Å; Z = 4; R = 0.0439, wR2 = 0.1211. PBO: C14H24N2O4.H2O; P212121; a = 6.157(2) Å, b = 11.547(4) Å, c = 23.408(8) Å; Z = 4; R = 0.050, wR2 = 0.1379. PDAVA: C16H28N2O4.H2O; P21212; a = 11.33(1) Å, b = 25.56(2) Å, c = 6.243(6) Å; Z = 4; R = 0.0919, wR2 = 0.2344. BGABU: C14H24N2O5; P61; a = 9.759(2) Å, b = 9.759(2) Å, c = 29.16(1) Å; Z = 6; R = 0.0773, wR2 = 0.1243. Chapter 7 describes the crystal structures of a dipeptide, Boc-Aib-γAbu-OH (UG) and a tripeptide, Boc-Aib-γAbu-Aib-OMe (UGU) containing a single γAbu residue in each sequence. The structure of UG forms a reverse turn stabilized by a 10-membered intramolecular C-H…O hydrogen bonded ring. The peptide UGU crystallized in the triclinic space group P⎯1 with two molecules in the asymmetric unit resulting in a parallel assembly of sheets in crystals. Notably, the insertion of a single Aib residue at the C-terminus drastically changes the overall conformation of the structures. Crystal parameters UG: C13H24N2O5; P21/c; a = 16.749(3) Å, b = 5.825(1) Å, c = 16.975(3) Å; β = 111.82(1); Z = 4; R = 0.0507; wR2 = 0.1294. UGU: C18H33N3O6; P⎯1; a = 9.576(6) Å, b = 13.98(1) Å, c = 17.83(1); α = 85.31 (1); β = 77.46 (1); γ = 71.39 (1); Z = 4; R = 0.0648; wR2 = 0.1837.

L'Infarctus du myocarde (IM) provoque, chez le rat, une augmentation de l'apoptose dans le système limbique en plus d'induire des symptômes qui s'apparentent à la dépression chez l'humain. Nous avons démontré qu'une diète élevée en oméga-3 ou la prise de probiotiques pouvaient être efficaces pour réduire ces effets si ces interventions débutaient avant l'induction de l'ischémie myocardique. Cette étude a pour objectif de déterminer l'efficacité de ces interventions si elles débutent après l'ischémie myocardique. L’IM a été induit chez le rat mâle Sprague-Dawley par l’occlusion de l’artère coronaire descendante antérieure gauche pendant 40 minutes. À la suite de l’ischémie, les rats ont reçu des probiotiques (1 billion de bactéries vivantes de L. helveticus R0052 et de B. longum R0175) ou un véhicule dans leur eau de boisson en présence d'une diète élevée ou faible en oméga-3. À 3 jours post-IM, l’activité enzymatique de la caspase-3 et le nombre de cellules dUTP nick-end labelling (TUNEL) positives sont diminués dans les régions CA1 et le corps godronné de l’hippocampe ainsi que dans l’amygdale en présence de la diète élevée en oméga-3. La prise de probiotiques atténue également l’activité de la caspase-3 et le nombre de cellules TUNEL positives dans le corps godronné et l’amygdale médiane. À 2 semaines post-IM, le comportement dépressif évalué par 3 tests comportementaux (test d’interaction sociale, test de nage forcée et test d’évitement passif) a été observé chez le groupe recevant la diète faible en oméga-3 sans probiotiques et le comportement dépressif a été atténué avec la diète élevée en oméga-3 et/ou la prise de probiotiques. Les probiotiques ont augmenté les niveaux plasmatiques d’interleukine-4 (IL- 4) tandis que la diète élevée en oméga-3 a montré une diminution de la protéine chimiotactique monocytaire 1 (MCP-1). Ces résultats indiquent qu’une diète élevée en oméga-3 ou la prise de probiotiques, débutant à la suite de l’IM, s’avèrent bénéfiques pour atténuer la dépression et l’apoptose dans le système limbique. / Proinflammatory cytokines play a central role in depressive-like behavior and apoptosis in the limbic system after myocardial infarction (MI). Polyunsaturated fatty acids (PUFA) omega-3 diet or the combination of Lactobacillus helveticus R0052 and Bifidobacterium longum R0175 probiotics, when given before ischemic period, reduce circulating proinflammatory cytokines as well as apoptosis in the limbic system. This study was designed to determine if the same nutritional interventions maintain their beneficial effects when started after the onset of the reperfusion period and attenuate depressive-like behavior. MI was induced by the occlusion of the left anterior descending coronary artery for 40 minutes in rats. After the onset of reperfusion, animals were fed with a high or low PUFA omega-3 diet, combined or not with 1 billion live bacteria of L. helveticus R0052 and B. longum R0175. At 3 days post-MI, caspase-3 enzymatic activities and terminal dUTP nickend labelling (TUNEL)-positive cells were decreased in the CA1, dentate gyrus and amygdala with the high PUFA omega-3 diet as compared to the other diet. Probiotics attenuated caspase-3 activity and TUNEL-positive cells in the dentate gyrus and the medial amygdala. At 2 weeks post-MI, depressive-like behaviour, evaluated by 3 behavioural tests (social interaction, passive avoidance and forced swim test), was observed in the low PUFA omega-3 diet without probiotics and this behavior was attenuated with the high PUFA omega-3 diet or/and probiotics. Probiotics increased interleukin-4 plasmatic concentrations while high PUFA omega-3 diet decreased monocyte chemotactic protein 1 (MCP-1). These results indicate that a high PUFA omega-3 diet or the administration of probiotics, starting iii after the onset of reperfusion, are beneficial to attenuate post-MI depression and apoptosis in the limbic system.

The aerospace industry has been concerned with propeller noise levels for years. This interest is two-fold: government regulation and comfort in cabin. This report attempts to create a simulation mechanism needed to evaluate the far-field noise generation levels. However, in order to do that, the tandem cylinder case was evaluated first as a validation step before the SR-7A propeller case was performed. Both cases use STAR-CCM+, a commercial software, to perform the simulations.

This thesis has addressed several of the fundamental challenges in correlating the structure thermal transport properties of complex nanoporous polycrystalline zeolite materials. Two types of zeolite materials, MFI and LTA, were employed in order to investigate the effects of temperature and both the framework and non-framework cations on the thermal conductivity of zeolite. The thermal conductivity values of both materials were measured using a well intergrown zeolite film 3-omega method. The thermal transport mechanisms in these materials were investigated by separately analyzing the contributions of different phonon scattering processes. This thesis represents our progress towards a robust framework for understanding and predicting thermal transport properties of zeolite materials and complex crystals in general. Furthermore, the important roles of boundary and defect scattering, as illustrated in this thesis, also imply that the thermal conductivity of zeolite materials can be tuned by exploiting not only the composition but also the pore structure. In addition, a non-equilibrium molecular dynamics simulation with external force was developed and employed to predict the thermal conductivity of materials. It has shown that this method can accurately predict the thermal conductivity of simple materials, such as argon and quartz; however, it failed to predict the thermal conductivity of complex materials, such as zeolite. This thesis presents possible factors that can explain the phenomena and future recommendations to elucidate this issue.

Thesis (MNutr (Interdisciplinary Health Sciences. Human Nutrition))--University of Stellenbosch, 2006. / Background At least 40 - 80% of all cancer patients develop some degree of clinical malnutrition and cachexia. The complex and multi-factorial nature of cancer cachexia and the inability of conventional nutrition intervention to reverse or attenuate the effects of this syndrome have driven investigators to consider new therapies and approaches to manage the syndrome of cancer cachexia including eicosapentaenoic acid (EPA), an n-3 fatty acid of fish oil origin. Objectives The aim of this study was to review Phase I, Phase II and Phase III (RCT) trials investigating the safety and efficacy of n-3 supplementation in the treatment of cancer cachexia in adult patients with unresectable solid tumours, with special reference to weight loss, body composition, appetite, dietary intake, energy expenditure, functional status, acute phase response and quality of life. Adverse effects associated with EPA supplementation were also reviewed. Methodology and data collection The major databases were systematically searched for studies that met the inclusion criteria using a structured keyword search strategy or various combinations of these keywords. Relevancy of studies was assessed by two independent reviewers according to pre-determined inclusion and exclusion criteria. Quality was assessed by two independent reviewers using the Jadad scale. Data extraction was performed by the principal reviewer and one of the independent reviewers, and investigators of the included studies were contacted where further information was required. Meta-analysis was not appropriate due to heterogeneity of the data. However, where possible, the paired t-test was used for analysis of the data. Descriptive or non-quantitative analysis of the tabulated data provided a summary of the characteristics of the included studies enabling comparisons to be made between interventions and outcomes within the specified population. Results The search resulted in a total of 1408 citations, of which only 16 studies met the inclusion and exclusion criteria. Of these, only 4 studies were of a good quality. Although the reported data was incomplete and variable, the combined analyses suggested that the effect of EPA supplementation on weight, fat mass, dietary intake, energy expenditure, and acute phase response was not significant. Interestingly there appeared to be a significant increase increased or decreased? in lean body mass (p<0.05). There was little or no data to draw any conclusions regarding the effect of supplementation on appetite and quality of life. Conclusion Despite several limitations in this review, the data collected and analysed are suggestive of the beneficial effects of EPA supplementation, but there remains a significant lack of substantial evidence and conclusive statistical analysis to confirm that EPA supplementation is a safe and effective method of intervention in the management of patients with cancer cachexia.

Thesis (MNutr)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Background: Omega-3 fatty acids and supplementation is very topical, attracting both public and interest from the industry. Findings from various research studies led a number of authorities to encourage the general population to consume more omega-3. This is the first study of its kind to be conducted in this population. Objective: To determine the current knowledge and trends of omega-3 (n-3) supplementation in parents of children at public primary schools in the City of Cape Town. Design: An observational and analytical and descriptive and cross-sectional study was performed. Methods: Purposive sampling was used to select a minimum of 150 parents from the six (6) randomly selected public primary schools. The schools were then divided into three different living standard measure (LSM) groups. The research questionnaire was made available at the Parent Teachers meetings where all parents had the option to complete the questionnaire anonymously at the meeting. Results: Six hundred and fifty seven (n=657) parents, mostly mothers, with a mean age of 37 years, completed and returned the questionnaires. The mean monthly income (p=0.00, SD=2.63) and the education level (p=0.00, SD=1.37) differed significantly between each of the three LSM groups. Prior to the study, 80.1% of parents (n=526) had heard of omega-3 supplements and overall knowledge of omega-3 was significantly better in this group (p=0.00) when compared to the group that had not heard of omega-3 previously. The overall mean omega-3 knowledge score for the three LSM groups (n=657) was 71%. The high and low LSM groups differed significantly in terms of omega-3 knowledge (p=0.02), but not statistically significantly once adjusted for income and education level (p=0.75). The main sources of information, where all parents (n=526) indicated having heard of omega-3 supplements, was from television (n = 230, 35%), books (n= 220, 33.5%) and the health worker (n=199, 30.3%). A total of 38.5% (n=253) of parents indicated that they gave their children omega-3 supplements. The overall omega-3 knowledge was significantly better (p=0.00) in parents who gave their children omega-3 supplements than the group that did not give supplements to their children. Income and the education level differed between all three LSM groups for those giving their children omega-3 supplements, but these variables did not influence the choice to give omega-3 supplements. Doctors (n=58, 22.9%) and the parents’ own decision (n=60, 23.7%) to supplement were the most favoured sources of recommendation indicated overall. Most parents indicated that the omega-3 supplement they administered was from a marine source (n=105, 41.5%). Only 35.2% (n=89) of parents giving omega-3 supplements indicated they knew the dose they were administering. Most of the children (n=90) were taking 500 mg omega-3 supplements daily. Conclusions and Recommendations: Statistically significant differences existed between the three LSM groups regarding various aspects of omega-3 knowledge and the sources from which parents had been informed and those who gave their children omega-3 supplements. Recommendations include education and public health programs supplying information to parents on omega-3 supplementation, as well as on omega-3 in the children’s diets. / AFRIKAANSE OPSOMMING: Agtergrond: Omega-3 vetsure en supplementasie is ‘n baie aktuele onderwerp, wat beide die belangstelling van die publiek en industrie betrek. Bevindinge van verskeie navorsingstudies het daartoe gelei dat verskeie instansies die algemene publiek aanmoedig om meer omega-3 in te neem. Dit is die eerste studie van sy soort wat in dié populasie groep gedoen is. Doelwit: Om die huidige kennis en tendensies/neigings in omega-3(n-3) supplementasie in ouers van kinders by publieke laerskole in die stad Kaapstad te bepaal. Ontwerp:’n Waarnemende- en en analitiese en beskrywende- dwarsdeursnitstudie is gedoen. Metode: Daar is gebruik gemaak van ‘n doelgerigte steekproefneming om ‘n minimum van 150 ouers uit ses (6) ewekansig geseleteerde publieke laerskole van uit te kies. Die skole is in drie verskillende lewenstandaardgroepe (LSM) verdeel. Die navorsingsvraelys is by ‘n Ouer-Onderwyservergadering beskikbaar gestel en alle ouers het ‘n geleentheid gehad om die vraelys anoniem by die vergadering te voltooi. Resultate: Seshonderd sewe-en-vyftig (n=657) ouers, meestel moeders, met ‘n gemiddelde ouderdom van 37 jaar, het die vraelyste voltooi en teruggegee. Die gemiddelde maandlikse inkomste (p=0.00, SD=2.63) en vlak van opvoeding (p=0.00, SD=1.37) het noemensvaardig tussen elk van die drie LSM groepe verskil. Voor die studie het 80.1% van die ouers (n=526) al van omega-3 supplemente gehoor en die algehele kennis van die groep was beduidend beter (p=0.00) as die groep wat voorheen nie van omega-3 gehoor het nie. Die gemiddelde algehele omega-3 kennistelling vir die drie LSM groepe was 71%. Die hoë en lae LSM groepe het beduidend ten opsigte van omega-3 kennis (p=0.02) verskil, maar nie statisties- beduidend wanneer dit vir inkomste en opvoedingsvlak (p=0.75) aangepas is nie. Die hoofbronne van inligting waar al die ouers (n=526) wat aangedui het dat hulle van omega-3 supplementasie gehoor het, was deur televisie (n=230, 35%), boeke (n=220, 33.5%) en die gesondheidswerker (n=199, 30.3%). ‘n Totaal van 38.5% (n=253) ouers het aangedui dat hulle hul kinders omega-3 supplemente gee. Die algehele omega-3 kennis van ouers wie hulle kinders omega-3 supplemente gee was statisties beduidend beter (p=0.00) in vergelyking met die groep wat nie supplemente vir hulle kinders gee nie. Die inkomste en opvoedingsvlak het verskil tussen all drie LSM groepe wat hulle kinders omega-3 supplementasie gegee het, maar hierdie veranderlikes het nie die keuse om omega-3 supplemente te gee beïnvloed nie. Mediese dokters (n=58, 22.9%) en die ouer se eie besluit (n=60 23.7%) om te supplementeer, was die gunsteling bronne van aanbeveling in die algemeen. Die meeste ouers het aangedui dat die omega-3 supplement wat hulle gegee het van ‘n visbron afkomstig (n=105, 41.5%) is. Net 35.2% (n=89) van die ouers wat omega-3 supplemente gee het aangedui dat hulle die dosis kenwat hulle gee. Meeste van die kinders (n=90) het 500mg omega-3 supplemente daagliks gekry. Gevolgtrekking en aanbevelings: Statistiese beduidende verskille is tussen die drie LSM groepe ten opsigte van verskeie aspekte van omega-3 kennis en bronne waaruit ouers ingelig is, sowel as die ouers wie hulle kinders omega-3 supplemente gegee het, gevind. Aanbevelings sluit opvoeding en publieke gesondheidsprogramme in, wat inligting aan ouers sal verskaf oor omega-3 supplementasie sowel as omega-3 in die kinders se diëte.

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Made available in DSpace on 2010-04-20T20:51:08Z (GMT). No. of bitstreams: 3 154942.pdf.jpg: 18952 bytes, checksum: 23e574558dce7d0f2a386af838a81bbe (MD5) 154942.pdf: 506907 bytes, checksum: 04eae2214c9bdd57e0cbeb2bb4459728 (MD5) 154942.pdf.txt: 81444 bytes, checksum: 047630fc773c90c68757120835adddab (MD5) Previous issue date: 2006-02-15T00:00:00Z / Mutual funds performance evaluation is, traditionally, made using Sharpe Ratio that considers only the first and the second moments of the return distribution (mean and variance), but it requires assumptions on the normality of the returns distribution and on the investor’s utility function as quadratic. However, it is well known that a quadratic utility function is inconsistent with investor behavior and some funds, like hedge funds, have returns distributions far from a normal distribution Keating and Shadwick (2002a, 2002b) proposed a new measure called Omega that incorporates all the moments of the distribution, and has the advantage of requiring no assumptions on the returns distribution or on the utility function of a risk averse investor. The purpose of this work is to verify if this measure has a greater forecast power than other performance measures, like Sharpe and Sortino Ratios. The empiric study indicated that Omega measure makes a ranking, most of the time, different from the other measures. Despite the portfolios constructed with Omega have had an average return greater than the average return of the portfolios constructed using the other measures, in almost all the tests, this difference of averages of returns was significant only in some cases. In spite of this, there is a light indication that Omega measure is the most appropriate for the use of investors when is made the performance evaluation of mutual funds. / A avaliação de desempenho de fundos de investimentos é, tradicionalmente, realizada utilizando-se o Índice de Sharpe, que leva em consideração apenas os dois primeiros momentos da distribuição de retornos (média e variância), assumindo as premissas de normalidade da distribuição de retornos e função quadrática de utilidade do investidor. Entretanto, é sabido que uma função de utilidade quadrática é inconsistente com o comportamento do investidor e que as distribuições de retornos de determinados fundos, como os hedge funds, estão longe de serem uma distribuição normal. Keating e Shadwick (2002a, 2002b) introduziram uma nova medida denominada Ômega que incorpora todos os momentos da distribuição, e tem a vantagem de não ser necessário fazer premissas sobre a distribuição dos retornos nem da função de utilidade de um investidor avesso ao risco. O objetivo deste trabalho é verificar se esta medida Ômega tem um poder de previsibilidade maior que outras medidas de avaliação de desempenho, como o Índice de Sharpe e o Índice de Sortino. O estudo empírico indicou que a medida Ômega gera um ranqueamento, na maioria das vezes, relativamente diferente das outras medidas testadas. Apesar das carteiras formadas com base na medida Ômega terem gerado um retorno médio maior que o retorno médio das carteiras formadas pelas outras medidas em praticamente todos os testes, esta diferença entre as médias dos retornos só foi significativa em alguns casos. Mesmo assim, há uma leve indicação de que a medida Ômega é a mais apropriada para utilização do investidor ao fazer a avaliação de desempenho dos fundos de investimentos.

Introdução: Epilepsia é uma desordem cerebral caracterizada predominantemente pela interrupção paroxística do funcionamento normal do cérebro causada por crises epilépticas que ocorrem de maneira recorrente e imprevisível. Aproximadamente 50% dos adultos com epilepsia têm ao menos uma comorbidade médica associada, e algumas condições apresentam uma prevalência maior quando comparados à população em geral. Entre elas podemos citar as comorbidades psiquiátricas e as alterações nutricionais. Objetivos: O presente estudo avaliou o consumo alimentar de pacientes portadores de epilepsia, e de forma mais específica, o consumo dos ácidos graxos poli-insaturados (PUFAS), e a sua relação com a presença de transtornos neuropsiquiátricos. Métodos: Foi realizado um estudo transversal onde o consumo alimentar de paciente com epilepsia do lobo temporal foi avaliado por um questionário de frequência alimentar (QFA) validado para a população de Porto Alegre –RS. Também foi avaliado a presença de transtornos psiquiátricos e sintomas de ansiedade através dos questionários estruturados, SCID, BAI e Escala de Hamilton. Resultados: Pacientes com diagnóstico de transtornos psiquiátricos avaliado por SCID apresentaram menor consumo de ácidos graxos omega-3, (0,53 ± 0,34g vs 0,84 ± 0,58g; p=0,047) e (0,21g ± 0,13g/1000kcal vs 0,32±0,21g/1000kcal; p=0,049). Pacientes com maiores níveis de ansiedade avaliados pelo BAI também apresentaram menor ingestão de PUFAS n-3 (9,14 ± 3,65g vs 12,82 ± 4,84g; p=0,011 e 3,41 ± 1,21% vs 4,14 ± 1,05% do VET; p=0,04). A Escala de Hamilton apresentou correlação inversa ao consumo de PUFAS n-3 (-0,306; p=0,041). Conclusão: Foi identificada uma associação entre o consumo de PUFAS n-3 e a presença de transtornos psiquiátricos e níveis mais altos de ansiedade em pacientes com epilepsia do lobo temporal. Ainda que o nosso estudo não pode determinar uma relação de cause efeito entre alterações neuropsiquiátricas e consumo de PUFAS é possível que um consumo de alimentos ricos em Omega-3 possa ser uma estratégica terapêutica a fim de melhorar anormalidades neuropsiquiátricas nesses pacientes. Essa é uma interessante questão que necessita ser melhor avaliada no futuro. / Background: Epilepsy is a brain disorder characterized by recurrent and unpredictable interruptions of normal brain function. About 50% of the adults patients with epilepsy have one or more coexisting medical conditions. Among the comorbidities, we highlight nutritional problems as well psychiatric disorders, which have a significant impact in the life quality of this patient. Aims: The aim of this study is to evaluate the nutritional intake of lobe temporal epilepsy patients and investigate its relation with psychiatric disorders diagnosis. Patients and Methods: we performed a cross-sectional study with 45 temporal lobe epilepsy patients and applied a food frequency questionary (FFQ), comparing the results with psychiatric diagnosis assessed by SCID to any disorders and depression by BAI and Hamilton Scale for anxiety. Results: All patients had a higher consumption of calories (38,89 ± 15,44). than the preconized for people in general and a lower intake of PUFAS than the recommended for cardiovascular protection. Patients identified with any psychiatric disorder by SCID had a lower intake of PUFAS n-3 (0,53 ± 0,34g vs 0,84 ± 0,58g; p=0,047 and 0,21g ± 0,13g/1000kcal vs 0,32±0,21g/1000kcal; p=0,049 than those free of diagnosis. Patients with high levels of anxiety also had also had a lower consumption of PUFAS n-3 (9.14 ± 3.65g vs 12.82 ± 4,84g; p=0.011). The Hamilton Scale had a negative correlation with PUFAS n-3 intake (0,306; p=0,041). Conclusion: We found a negative relation between the diagnosis of psychitric disorders and anxiety as assessed by SCID and BAI respectively. It’s not possible to determine a cause and effect relationship in this association, but we can consider the omega-3 fat acid and PUFAS n-3 rich food might be potentially therapeutic in patients with temporal lobe epilepsy. This question might deserve further studies.