Retention of lipid-soluble components can be increased in a curd matrix by using emulsions rather than the direct addition of fortified oil. The retention of vitamin D_3 was increased in a model system with fortified emulsions (emulsifier: dairy proteins) 96-97% compared to 62-72% control. Retention of fortified emulsions (78%) remained greater than the control (58%) in small-batch Cheddar cheese. Bilayer emulsions were evaluated to increase retention of lipid-soluble components even further. Physicochemical characteristics of the bilayer emulsions were evaluated prior to curd inclusion. Nonfat dry milk (NDM) was used as the primary emulsifier at 1wt% dairy proteins. Polysaccharides (iota-carrageenan, low-methoxyl [LMp] and high-methoxyl pectin) and gelatin were secondary layers. Secondary emulsions formulation was 2.5 wt% oil, 0.5 wt% protein, and 0.2 wt% secondary biopolymer. Emulsions were adjusted to pH 3, 5, and 7 after homogenization. Factors that influence stability are biopolymer concentration, droplet size/distribution/charge (zeta-potential), and viscosity. iota-Carrageenan was the most stable, independent of pH, of all the emulsions. This increased stability was a consequence of the affinity of the protein layer and iota-carrageenan through the additional homogenization step. LMp was also stable at pH 7 due to calcium bridging, which correlates with the increased viscosity. The microstructure of the emulsions was examined using scanning electron microscopy. A strong correlation was found between emulsion instability and the presence of thick webbing, due to excess biopolymer, as seen in the micrographs. Stable emulsions were likely to have distinct droplets without a thick web. The exception was gelatin (pH 3), which still had individual droplets but was unstable due to depletion flocculation. The retention of lipid-soluble substances using secondary emulsion was evaluated in a model curd matrix between primary (50:50 fortified: non-fortified oil) and secondary (100% fortified oil) emulsions. There was no significant difference (α=0.05) in retention of “fortified” oil between primary and secondary emulsions; however, the same fortification level was obtained using secondary emulsions using half the oil. Curd made with 0.01M CaCl_2 had overall lower retention than curd with no additional calcium. Secondary emulsions could be used to fortify various gel matrices (e.g., curd, yogurt, and tofu). Marketing possibilities are endless after preliminary evaluation.

<p> An experimental study of the steric stabilizing ability of a water soluble polyvinyl alcohol (PVA) polymer is presented.</p> <p> The free film thickness of a lamella formed between a drop of n-butylchloride and bulk n-butylchloride stabilized by PVA was measured by the Hodgson and Woods technique in order to evaluate the stabilizing ability of the polymer. A maximum in the stability was observed as the concentration of the polymer was increased. This maximum trend can be explained by the HVO theory.</p> / Thesis / Master of Engineering (MEngr)

<p> Filtered final effluent was chlorinated at various doses using calcium and sodium hypochlorite in order to study the effect of chlorination on the soluble organics present in final effluents. The biochemical oxygen demand (BOD) was measured over a period of five days and carbon analyses (TOC) were performed during the course of the reaction. Chemical oxygen demand tests (COD) on filtered chlorinated-dechlorinated and unchlorinated sewage at various doses were also performed. It was found that chlorination did not bring about a BOD5 reduction nor rendered the soluble organics bioresistant or toxic to micro-organisms, owing to the presence of ammonia, as there was no significant difference in the extent of carbon degradation. The COD as well as TOC before and after chlorination remained unchanged indicating that there was no loss of organic content due to chlorination.</p> <p> The pure compounds, glutamic acid, alanine, histidine, glycine, ammonia, phenol, n-butylamine, acetic acid and maleic acid were chlorinated at various chlorine doses in the presence and absence of ammonia and with chloramines. Glutamic acid and phenol were chlorinated at various pH levels. The oxidation of glycine by sodium hypochlorite was also studied. It was found that pH influences the rate of reaction considerably and that the presence of ammonia, whether free or combined as chloramines, slowed down the rate and prevented the oxidation of glycine from occurring.</p> <p> The effect of chlorine residuals on the seed micro-organisms was also investigated. Three levels of residuals, 0.2, 0.5 and 0.8 mg/1 available chlorine, were employed. The chlorine demand of the sewage was satisfied prior to the addition of these residuals. The BOD was also monitored over a period of five days. The results indicated that longer lag phases resulted from the application of higher residuals and the lowest BOD was observed to occur at the highest residual. However, some microorganisms survived chlorination as evidenced by the exertion of a BOD at the 0.8 mg/1 available chlorine level.</p> <p> The seeding technique employed by previous workers for measuring the BOD5 of unfiltered chlorinated-dechlorinated sewage was also investigated. It was found that even when the unchlorinated sample was not seeded, it contained a higher microbial concentration as evidenced by plate counts performed on both chlorinated-dechlorinated seeded and unchlorinated unseeded samples at two dilutions commonly employed in BOD5 determinations. Associated with these results was a BOD4 reduction of about 2.2 mg/1/mg/1 Cl absorbed. Seeding of the samples, at best, provides a uniformly mixed microbial population but not necessarily a uniform microbial concentration. These results could possibly explain the BOD5 reductions observed on unfiltered chlorinated effluents.</p> / Thesis / Master of Engineering (MEngr)

The complex [IrH(COD)(PMe3)3][Cl]2o2HCl was prepared by the reaction between [Ir(COD)(PMe3)3]Cl and HCl gas in methylene chloride. The product precipitated from the solution and is soluble in polar solvents such as water, acetonitrile, and acetone. [IrH(COD)(PMe3)3][Cl]2o2HCl undergoes reaction in water to form fac-IrCl3(PMe3)3. Also, other [IrH(COD)(PMe3)3][X]2 salts were prepared with X being PF6, OTF, or BF4. It was determined that each salt retained a certain amount of excess acids and [IrH(COD)(PMe3)3][OTF]HOTf was the most stable in the solvent acetonitrile while [IrH(COD)(PMe3)3][PF6]2 showed signs of reaction in acetonitrile after 4 hours. The dicationic salts were also reductively deprotonated by DMSO to form the Ir(I) starting material. Finally a slow equilibrium was noted for [IrH(COD)(PMe3)3][BF4]2 in water by the observation of the reductive deprotonation product. The grignard reaction was employed to synthesize Ir(CH3)3(PMe3)3. IrCl3(PMe3)3 reacts with methyl grignard in THF/Benzene to form fac-Ir(CH3)3(PMe3)3. Only the facial isomer of this reaction was observed and the product was soluble in nonpolar solvents. Acidolysis was utilized to synthesize fac-IrCH3Cl2(PMe3).3 from the reaction between Ir(CH3)3(PMe3)3 and 2 equivalents of HCl. Ir(III) methyl dications have also been synthesized by the reaction of 2 equivalents triflic acids with fac-Ir(CH3)3(PMe3)3. The product of the reaction, mer-IrCH3(OTf)2(PMe3)3 was used to study the insertion of alkynes into the Iridium methyl bond. IrHCl2(PMe3)3 was synthesized by the careful acidolysis of IrH2Cl(PMe3)3 using 1 equivalent of HCl. IrH(OTf)2(PMe3)3 was also synthesized by the metathesis of IrHCl2(PMe3)3 with 2.04 equivalents of silver triflate. The product of that reaction, IrH(OTf)2(PMe3)3, has been used to form dimers and trimers of styrene via catalysis and to isomerize alkene alcohols to aldehydes. IrH(OTf)2(PMe3)3 was also used as a polymerization initiator for vinyl and allyl ethers. / Ph. D.

Manganese(II) complexes formed by the reaction of either salicylaldehyde or 5-chlorosalicylaldehyde and 1,4-diaminobutane (SALBTDA), 1,6-diaminohexane (SALHXDA), 1,8- diaminooctane (SALOTDA), and 1,10- diaminodecane (SALDCDA) have been isolated. The complexes Mn(SALHXDA), Mn(SALOTDA), and Mn(SALDCDA) rapidly darken upon exposure to air. Mn(SALBTDA), Mn(5C1SALHXDA), Mn(5C1SALHTDA), and Mn(5C1SALOTDA) are stable in air when dry. When suspended in DMSO all complexes, with the exception of Mn(SALBTDA), react with oxygen to form Mn(IV) complexes. All of the complexes react with oxygen when in solution. The rates of oxygenation of the complexes were studied in the solid state, as DMSO suspensions, and in pyridine solution. A two step oxygenation with a proposed manganese(III) intermediate was observed for all complexes in all systems. These results have been correllated with oxygenations of Mn(SALEN), Mn(SALTM), Mn(SALPTDA), and Mn(SALHTDA) from the reaction of salicylaldehyde with ethylenediamine, 1,3-diaminopropane, 1,5-diaminopentane, and l,7-diaminoheptane, respectively. The structure of the oxygenated complexes are prpposed to be polymeric with μ dioxo bridges between manganese atoms. / Master of Science

L’implication d’un facteur circulant et des dysfonctions du système immunitaire entrainant les altérations de la barrière de filtration glomérulaire a été suggérée dans la pathogénèse de la hyalinose segmentaire et focal récidivante. Nous avons identifié par spectrométrie de masse la présence de la protéine CASK dans des sérums de patients après immunoadsoroption sur une colonne de protéine A. CASK recombinante est capable d'induire des modifications de l’architecture des podocytes in vitro, tels qu’une redistribution de la protéine de diaphragme de fente ZO-1 et de la protéine régulatrice d’actine synaptopodine, et une perte de fibres de stress d’actine. Ces podocytes acquièrent ainsi un phénotype motile et une perméabilité accrue à l’albumine en présence de CASK recombinante in vitro. L’injection de CASK chez des souris entraine une protéinurie et l’effacement des pédicelles de podocytes. L’interaction entre CASK et son récepteur CD98 dans les podocytes a été mise en évidence par l’expérience de pontage covalent et co-immunoprécipitation. L’inhibition de l’expression de CD98 par ARNi a permis de préserver l’architecture des podocytes en présence de CASK. Nous avons remarqué la surexpression de CASK dans les monocytes chez les patients atteints de la HSF récidivante par rapport aux témoins. In vitro, CASK est surexprimée dans les macrophages ayant une polarité M2 et est retrouvée dans le surnageant de la culture de ces cellules. La sécrétion de CASK est associée aux exosomes qui sont des microvésicules d’origine endosomale. Dans les cellules, CASK est partiellement co-distribuée avec ALIX, un marqueur exosomal, et leur interaction a été mise en évidence par co-immunoprécipitation. CASK est fortement exprimée dans les exosomes de patients atteints de HSF récidivante comparé aux donneurs sains. Le traitement des podocytes par des exosomes issus des macrophages de type M2 induit des altérations du cytosquelette et augmente la motilité des podocytes comme cela avait été observé en présence de CASK recombinante. Pour conclure, nous avons identifié CASK comme nouveau facteur soluble qui pourrait jouer un rôle au cours de la HSF récidivante après transplantation rénale. Ces découvertes ouvrent de nouvelles orientations pour le traitement des malades atteints de SNI récidivant. / Focal segmental glomerulosclerosis (FSGS) is often associated with a high rate of progression to end-stage renal disease. The idiopathic form has a high recurrence rate (rFSGS) after transplantation suggesting the presence of a systemic circulating factor that causes the glomerular permeability. This factor can be removed by plasmapheresis or immunoadsorption using protein-A columns. We used mass spectrometry to analyze the proteins eluted from protein-A columns, taken from patients with rFSGS after immunoadsorption. A serum form of calcium/calmodulin-dependent serine/threonine kinase (CASK) was identified in rFSGS patients but not in controls. In cultured podocytes, recombinant CASK induced reorganization of the actin cytoskeleton. We also demonstrated the interaction of CASK with CD98 at the cell surface. Injection of recombinant CASK in mice induced proteinuria and foot process effacement on podocytes. We identified that CASK is produced by monocytes in patients with rFSGS. CASK is also expressed and secreted by M2 polarized macrophages but not by M1 subset. CASK was associated with exosomes produced by these cells. CASK has a partial codistribution with ALIX, an exosomal component involved in their development. We’ve also demonstrated that CASK interacts with ALIX in M2 macrophages. Moreover exosomes derived from M2 macrophages cause podocytes cytoskeleton alterations and increase of podocyte motility as observed previously with recombinant CASK. In conclusion, a serum form of CASK secreted by macrophages acts as a permeability factor in patients with rFSGS suggesting its involvement in the physiopathology of rFSGS.

Des populations tolérante (métallicole: M) et sensible (non-métallicole: NM) d’Agrostis capillaris L. ont été exposées à des doses croissantes de Cu (1-50 μM) pour étudier la tolérance au Cu par une approche pluridisciplinaire. Selon les paramètres phénotypiques (biomasse, longueur des feuilles et symptômes visuels), les plantes M ont une meilleure croissance aux expositions supérieures à 10 μM Cu. Les concentrations en Cu des tissus reflètent une rétention racinaire (phénotype d’exclusion) et une réduction de la translocation vers les feuilles quand le stress augmente. En excès de Cu, le protéome soluble racinaire présente des altérations du métabolisme énergétique chez M et NM, plus marquées chez NM (glycolyse, cycle de Krebs /phosphorylation oxydative). Le protéome foliaire indique des impacts sur les phases claires et obscures de la photosynthèse chez M et NM, et un besoin plus important en acides aminés soufrés (augmentation des cystéine et méthionine synthases). Chez NM, l’augmentation d’enzymes de la glycolyse, de la voie des pentoses phosphates et du cycle de Calvin indiquent un besoin énergétique accru, tandis que la stimulation des chaperonnes et des processus de synthèse protéique suggère des impacts sur le métabolisme des protéines et celle des enzymes redox un stress oxydatif plus fort. Plusieurs protéines, surexprimées ou accumulées, interviendraient dans la tolérance au Cu chez M, en protégeant le métabolisme des protéines (HSP70, racines et feuilles) et en augmentant les mécanismes anti-oxydants (ascorbate péroxydases), de détoxification (GST et aldéhyde déshydrogénase) et de protéolyse (peptidase et protéasomes, racines). / Cu-tolerant (metallicolous: M) and sensitive (non-metallicolous: NM) populations of Agrostis capillaris L. were exposed to increasing Cu concentrations (1-50 μM) to investigate Cu tolerance by a pluridisciplinary approach. Phenotypic parameters (biomass production, shoot length, and visual symptoms) indicated a higher growth and a better fitness of M plants over 10 μM Cu. Plant Cu concentrations indicated root Cu retention (‘excluder’ phenotype) and a reduced root-to-shoot translocation with increasing Cu stress. Based on root soluble proteome energy metabolism was altered by Cu excess in both populations with stronger impacts in NM (glycolysis, Krebs cycle/oxidative phosphorylation). Changes in shoot proteome showed impacts on both light dependent and independent photosynthesis phases in both populations, and an enhanced need in S-containing amino-acids (up-regulation of cysteine/methionine synthases). In NM leaves, increase of enzymes involved in glycolysis, pentose phosphate pathway and Calvin cycle indicated a stimulation of energy metabolism, while enhanced protein synthesis processes and protein chaperones suggested impacts on protein metabolism and increase of redox enzymes indicated a higher oxidative stress. Several over-expressed or accumulated proteins may be pivotal for Cu tolerance in M plants, for protecting protein metabolism (Heat shock protein 70kDa, roots and leaves), increasing anti-oxidative (ascorbate peroxidases, roots) – detoxification (Glutathione S-transferase and aldehyde dehydrogenase, roots) and proteolysis (peptidase and proteasome subunits) processes.

Les femmes enceintes et les enfants sont les populations à haut risque pour le paludisme. Chez les premières, l'infection peut entraîner une infection placentaire (IP). Les enfants nés d'une mère ayant une IP seraient plus à risque de développer une infection palustre rapidement après la naissance. Un phénomène de tolérance immunitaire est évoqué mais aucune explication n'est émise. Nous proposons une explication basée sur l'implication de HLA-G, protéine de la tolérance immunitaire. Nous avons pu montrer que les niveaux élevés de HLA-G chez les enfants étaient associés à un risque élevé de paludisme et au faible poids de naissance. Il existe une très forte ressemblance mère-enfant au cours de la grossesse et durant les 2 premières années de vie de l’enfant avec une probabilité très élevé chez les enfants d’avoir le même profil que leur mère. Les femmes ayant une IP présentent un risque plus élevé d’avoir des enfants ayant des niveaux de HLA-G soluble élevé, et le délai de 1ère infection palustre est plus court pour les enfants nés de mères ayant un niveau de HLA-G élevé en début de grossesse. Ces résultats confirment que HLA-G est associée à l’infection palustre. Ils montrent que le rôle de HLA-G dans l’IP est très complexe. Face à la ressemblance mère-enfant et le délai de 1ère infection, il serait intéressant d’envisager le dosage de HLA-G maternel en début de grossesse afin de confirmer son rôle prédictif. HLA-G pourrait alors être un outil de santé publique intéressant pour identifier de potentiels futurs enfants à risque. / Pregnant women and children are populations at high risk for malaria. Malaria infection in pregnancy can lead to placental malaria (PM). Children born to a mother with PM have an increased risk of malaria infection during the first years of life. To explain this phenomenon related to an immune tolerance, we suggest an explanation based on the implication of HLA-G, an immune tolerance protein. We show that high levels of soluble HLA-G in children were associated with malaria risk and low birth weight. There is a very strong mother/child resemblance during pregnancy and the first 2 years of life of the child with a very high probability in children of having the same profile as their mother. Women with PM have a higher risk to give birth to a child with high levels of soluble HLA-G, and children born to mothers with high HLA-G levels have an increased risk of malaria in early pregnancy. These results confirm that HLA-G is associated with malaria infection. They show that the role of HLA-G in PM is very complex. According to the maternal-child resemblance and the delay onset the first infection, it would be interesting to consider the dosage of maternal HLA-G in early pregnancy in order to confirm its predictive role. HLA-G could then be an interesting public health tool to identify potential children at risk.

The successful application of Tppts, and its derivatives, in biphasic transition metal-catalysed reactions opened up a new field of chemistry requiring a rational design of water-soluble ligands. The main objective of the research described in this dissertation was the preparation and the application of new water-soluble phosphine ligands. The ligands were prepared by the use of carbon nucleophiles and chlorophenylphosphine derivatives. The carbon nucleophiles included malonate derivates, which were subsequently reduced to the di-alcohols and were transformed into water-soluble phosphines by the reaction with 1,4-butanesultone. Secondary and tertiary malonate nucleophiles were used and the steric demands of compounds containing more than one malonate group were investigated. Various attempts to obtain water-soluble compounds from dimalonate phosphine oxides failed. TBDMS-protected aryl halides were also used as nucleophiles. One (or two) of these silyl ethers was reacted with chlorophenylphosphine derivatives and after deprotection with TBAF the compounds were made water-soluble by a reaction with 1,4-butanesultone. The hydrogenation of arylphosphine oxides to form cyclohexylphosphine oxide derivatives was also investigated. However, these cyclohexylphosphines were more easily obtained by the reaction between the previously mentioned carbon nucleophiles and chlorocyclohexylphosphine derivatives, which were freshly prepared. A series of cyclohexyl-containing water-soluble phosphines was prepared in this way. The oxygen sensitive nature of phosphines lead to two different approaches in the reaction route: the phosphines were either borane protected followed by a subsequent deprotection step, or the phosphines were allowed to oxidise and were reduced back to the free phosphine at a later stage. The efficiency of both approaches in the reaction routes was examined. The deprotection of phosphine-boranes was performed using various “new” deprotecting reagents and the borane-species and free phosphines were separated using water/organic extractions. The various extraction coefficients of the amine-borane complexes were determined. The newly prepared ligands were used in a variety of palladium-catalysed reactions as well as in the hydroformylation of 1-octene employing rhodium. The reactions were performed in both neat organic solvents as well as mixtures between water and DMF or toluene and the results were compared to the use of Tpp and Tppts. It was found that many of the new ligands afforded superior yields compared to those of Tpp and Tppts. In the last part of the study, various diphenylphosphinic amides were used as DoM-groups. Sec- and tert-BuLi were used together with a variety of electrophiles to facilitate ortho-substitution on either one or two rings on the amides. This was seen as a start of a new approach towards functionalised phosphine ligands. / Prof. D.B.G. Williams

Through chemical analysis and ion exchange chromatography of watersoluble antigens, this investigation supports the view that the majority of differences between the biotypes are quantitative. It was also found that strains demonstrate distinct, qualitative differences when compared to the attenuated strain 19 by immunodiffusion and thin-layer polyacrylamide gel, isoelectric focusing. These differences include the presence of antigens on virulent strains that are absent on strain 19. In addition, one antigen absent on strain 19, was found common to each virulent biotype. Finally, the results from immunodiffusion experiments, employing adsorbed and non-adsorbed immune globulins, indicate that at least some water-soluble antigens are exposed on the cell surface and that their distribution among the biotypes varies.