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Exercise performance was examined after ingestion of 45 g of liquid carbohydrate (LCHO), solid carbohydrate (SCHO), or water (W) 5 min before 1 h of intense exercise.An (CHO) meal (200 g) taken 4 h prior to exercise was combined with a solid CHO feeding (M+SCHO). Ten well-trained male cyclists (4.35 + 0.11 1/min V02 max) performed 45 min of cycling at a work load requiring an average oxygen uptake of 77.1% V02 max followed by a 15 min performance ride. Serum glucose values were elevated by 18% and 24% during SCHO and LCHO, respectively, as compared to W. Blood glycerol concentrations were significantly (p<0.05) lower during M+SCHO and significantly higher during W at 40, 50 and 60 min of exercise as compared to all other trials. Muscle biopsies at 0 and 45 min revealed no significant differences in muscle glycogen concentration or total use between the 4 trials. Total work produced during the final 15 min of exercise was significantly greater during M+SCHO (194735 + 9448 NM) as compared to all other trials and significantly greater during LCHO and SCHO (175204 + 11780 and 176013 + 10465 NM, respectively) as compared to W (159143 + 11407 NM). Carbohydrate oxidation was highly correlated (r=0.94) with work production. These results suggest that exercise performance is enhanced with the ingestion of 45 g of CHO 5 min prior to one hour of intense cycling. Further improvements in performance were found when exercise was preceded by a CHO meal 4 h prior to exercise in combination with a solid CHO feeding given immediately before exercise.

Orientador: Aulus Cavalieri Carciofi / Banca: Ricardo Souza Vasconcellos / Banca: Aureo Evangelista Santana / Resumo: Este estudo avaliou os efeitos do consumo de amido resistente (AR) em cães adultos e idosos sobre a digestibilidade dos nutrientes, produtos de fermentação e respostas pós-prandiais de glicose e insulina. Uma formulação foi processada de dois modos, originando rações com baixo (0,21%) e elevado (1,46%) teores de AR. Os dados de consumo, digestibilidade e produtos de fermentação foram avaliados pela função GLM do SAS, considerando delineamento em blocos casualizados no tempo (cross over), com tratamentos no esquema fatorial em dois níveis de idade e dois níveis de ração. Utilizou-se análise de variância de medidas repetidas no tempo para avaliar os efeitos da dieta e do tempo sobre as respostas pós-prandiais de glicose e insulina. A digestibilidade aparente da proteína bruta foi maior na dieta baixo AR. Os cães adultos produziram fezes com maiores volume, umidade e pH, bem como maiores concentrações de ácido acético, ácidos graxos de cadeia curta e voláteis. A ração alto AR induziu fezes com maiores concentrações de ácidos propiônico e butírico; nos cães idosos também elevou a concentração de lactato, corroborando o menor pH das fezes deste grupo. A amônia fecal foi maior nos idosos; a ração alto AR reduziu estas concentrações neste grupo. As glicemias mínimas e médias foram maiores nos adultos, assim como as áreas abaixo da curva (AAC) de glicose nos períodos 0-120', 240-720' e 0-720'. Apenas nos idosos houve redução das AAC de glicose ao consumirem a ração alto AR. A AAC do ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This study evaluated the effects of resistant starch (RS) consumption in adult and elderly dogs on nutrient digestibility, fermentation products and postprandial glucose and insulin responses. The same formulation was processed in two different ways, producing diets with low (0.21%) and high (1.46%) RS levels. Consumption, digestibility and fermentation products data were evaluated by SAS GLM function considering a randomized block design in time (cross over), with treatments in a factorial design in two age levels and two feed levels. We used analysis of variance of repeated measurements over time to assess the effects of diet and time on postprandial glucose and insulin responses. The protein digestibility was greater in the diet with low RS. Adult dogs produced feces with higher volume, water content and pH, as well as higher concentrations of acetic acid, short chain and volatile fatty acids. Consumption of high RS diet produced faeces with higher concentrations of propionic and butyric acids, and in elderly group this diet also increased the concentration of lactate, corroborating the lowest pH of stools in this age group. Fecal ammonia was higher in the elderly dogs, and the consumption of high RS diet by this age group reduced these concentrations. The minimum and average blood glucose levels were higher in adult dogs, as well as glucose areas under the curve (AUC) during periods 0-120, 0-240', 0-720' and 420-720'. Only in the elderly the consumption of high RS diet re... (Complete abstract click electronic access below) / Mestre

by Ivan H.F. Chung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1995. / Includes bibliographical references (leaves 63-67). / Acknowledgements --- p.i / Contents --- p.ii / Abstract --- p.iv / Abbreviations --- p.v / Chapter Chapter I --- Introduction / Chapter I-1. --- General background --- p.1 / Chapter I-2. --- Asymmetric Diels-Alder reaction using chiral auxiliaries --- p.2 / Chapter I-2A --- Some well-known chiral auxiliaries --- p.3 / Chapter I-2B --- Carbohydrates as chiral auxiliaries --- p.6 / Chapter I-3. --- Asymmetric Diels-Alder reaction using chiral catalysts --- p.10 / Chapter Chapter II --- Results and Discussion --- p.14 / Chapter II-1. --- "Synthesis of η6-(benzyl 2-O-acryloyl-3,4-O-isopropylidene- β-L-arabinopyranoside) tricarbonylchromium(O) (47)" --- p.15 / Chapter II-2. --- "Syntheses of 4'-methylbenzyl 2-O-acryloyl-3,4-O- isopropylidene-β-L-arabinopyranoside (57) and η6-(4'- methylbenzyl 2-O-acryloyl-3,4-O-isopropylidene-β-L- arabinopyranoside) tricarbonylchromium(O) (56)" --- p.19 / Chapter II-3. --- "Syntheses of naphthylmethyl 2-O-acryloyl-3,4-O- isopropylidene-α-L-arabinopyranosides" --- p.22 / Chapter II-4. --- Diels-Alder reaction using the dienophiles 56 and 57 as the chiral auxiliaries --- p.25 / Chapter II-5. --- "Synthesis of benzyl 3,4-O-methylene-β-L-arabinopyranoside (81)" --- p.32 / Chapter II-6. --- Using the alcohol 81 as the ligand for Lewis acid in the Diels-Alder reaction --- p.36 / Chapter Chapter III --- Conclusions --- p.38 / Chapter Chapter IV --- Experimental Section --- p.40 / Chapter IV-1. --- Experimental section for the asymmetric Diels-Alder reaction using the chiral auxiliaries --- p.41 / Chapter IV-2. --- Experimental section for the asymmetric Diels-Alder reaction using the chiral catalysts --- p.59 / References --- p.63 / List of spectra --- p.68

by Fung Wing-chuen. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1994. / Includes bibliographical references (leaves 57-59). / Abstract --- p.i / Acknowledgments --- p.ii / Biography --- p.iii / Abbreviation --- p.v-vi / Chapter 1. --- Introduction / Chapter 1.1 --- Natural O-heterocycles --- p.1 / Chapter 1.2 --- Methods for the construction of O-heterocycles --- p.5 / Chapter 1.3 --- Intramolecular nitrone cycloaddition in the construction of O-heterocycles --- p.9 / Chapter 2. --- Results and discussion / Chapter 2.1 --- Introduction --- p.12 / Chapter 2.2 --- Synthesis of 68，77，84 Via INC --- p.13 / Chapter 2.3 --- Acyclic INC of nitrones --- p.16 / Chapter 2.4 --- "Studies on 7-, 8-membered rings formation" --- p.24 / Chapter 3. --- Conclusions --- p.29 / Chapter 4. --- Experimental --- p.34 / Chapter 5. --- References --- p.57 / Chapter 6. --- List of spectra --- p.60 / Chapter 7. --- Appendices --- p.72

by Yong-li Zhong. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (p. 234-246). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web.

O presente trabalho descreve o uso de carboidratos como materiais de partida para a preparação de catalisadores quirais e também de substratos quirais. Primeiramente estudos envolvendo a aplicação de amino álcoois derivados de carboidratos na arilação assimétrica de aldeídos, usando ácidos arilborônicos como fontes de grupos arila transferíveis, revelaram que um ligante preparado a partir da D-xilose mostrou-se bastante eficiente e conduziu aos produtos em excelentes rendimentos e altos excessos enantioméricos. Posteriormente a arilação de aldeídos derivados de carboidratos é descrita. Em alguns casos diastereosseletividades maiores que 20:1 foram observadas e a metodologia foi aplicada a síntese total da 7-epi-goniofufurona e análogos. / The work described herein is centered on the use of carbohydrates as starting materials for the synthesis of chiral ligands and chiral sugar-derivatives. Initially, chiral amino alcohols were studied as ligands for the asymmetric arylation of aldehydes using aryl boronic acids as the source of transferable aryl groups. We found that a chiral ligand derived from D-xylose was very efficient and the desired products were obtained in excellent yields and enantiomeric excesses. In addition, the arylation of sugar-based aldehydes was also studied. In many cases, excellent diastereoselectivities of >20:1 were achieved and the methodology was employed in the total synthesis of 7-epi-goniofufurone and analogues.

An enone was synthesized from delta-D-gluconolactone in four steps, involving a one-pot TPAP oxidation-K2CO3-mediated intramolecular Horner-Wadsworth-Emmons (HWE) olefination as the key step. / In this thesis, a review regarding intramolecular direct aldol reaction from 1971 to 2008 is presented. The background information on pseudo-acarviosin, valiolamine and its containing compounds, gabosines and human glutathione transferase (hGST) is introduced. / Intramolecular direct aldol reaction was investigated for the construction of cyclohexanones and cycloheptanones from carbohydrates. Amine bases, amide bases and L-proline were employed to facilitate cyclization of 1,5- and 1,6-diketones successfully. These 1,5- and 1,6-diketones were prepared from carbohydrates by standard transformations. Different bases were employed to promote cyclization of 1,5-diketone derived from D-glucose to give cyclohexanones stereoselectively. / Intramolecular nitrile oxide-alkene cycloaddition (INOC) was studied with sugar derivatives having free hydroxyl groups. The INOC reaction, by incorporating chloramine-T and silica gel for the formation of nitrile oxide from oxime, proceeded smoothly with one, two, and four unmasked hydroxyl groups to give cyclopentanes and cyclohexanes. / The polyhydroxylated carbocycles constructed from sugars were successfully transformed into a variety of target molecules including pseudo-acarviosin, valiolamine and its containing compounds and gabosines. A series of 2-crotonyloxymethyl-(4 R,5R,6R)-4,5,6-trihydroxy-2-cyclohexenone (COTC) analogues as inhibitors of hGST were prepared in order to study the structure-activity relationships. / Cheng, Hau Man. / Adviser: Tony K. M. Shing. / Source: Dissertation Abstracts International, Volume: 70-06, Section: B, page: 3508. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 214-224). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.

Wong Wai Fun. / "June 2006." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (p. 226-230). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese.

Glycosaminoglycans (GAGs) are linear polysaccharides found on most animal cell surfaces and in extracellular matrices. Their key biological roles include cell signalling, cell-to-cell recognition, bacterial and viral adhesion, and antibody production. They are composed of disaccharide repeating units, containing uronic acid and amino sugar residues, and may be highly heterogeneously sulfated. Protein-GAG complexes are thought to play an important role in a number of aspects of cancer development, but are an under-studied area due to a lack of enabling tools to facilitate their analysis as discussed in Chapter 1. To obtain homogenous GAG structures, a range of conditions for the separation of GAG oligosaccharides by Zwitterionic Hydrophilic Interaction Liquid Chromatography (ZIC-HILIC) were developed using commercial chondroitin sulfate standards; these are discussed in Chapter 2. Mixed-modal separation mechanisms were explored across a different buffer compositions and elution programs to optimise the conditions to suit individual classes of native and modified glycosaminoglycans. These methods were then applied to the separation of chondroitin sulfate mixtures and heparin oligosaccharides. ZIC-HILIC may also be coupled to Mass Spectrometry to produce an online analytical method for GAG mixtures. A range of optimised conditions for the analysis of low molecular weight glycosaminoglycan oligosaccharides by Electrospray Mass Spectrometry were developed using commercial chondroitin sulfate disaccharide standards; as discussed in Chapter 3. These conditions were then employed in the tandem mass spectrometry (MS/MS) of chondroitin sulfate to identify diagnostic fragmentation patterns and this was applied in the characterisation of chondroitin sulfate disaccharides derived from enzymatic cleavage. The position of ring substituents can also be identified using this methodology, which is desirable in the analysis of chemically-labelled GAG structures. To allow for high resolution EPR and NMR studies of protein-GAG interactions, synthetic procedures for the incorporation of paramagnetic centres into GAG oligosaccharides and proteins were developed and these are discussed in Chapter 4. A propargyl-modified lysine was synthesised for recombinant expression into myoglobin. Copper-Catalysed Azide-Alkyne Cycloaddition (CuAAC) was employed in the spin labelling of myoglobin, however traditional experimental conditions were found to reduce the TEMPO-based spin labels used. Alternative conditions were developed using glutathione to stabilise the copper (II) catalyst without reducing the spin label. Spin labelling of the modified lysine was monitored by EPR. Modification of the non-reducing end was explored for the spin labelling of GAG oligosaccharides, to avoid the ring opening that typically occurs in reducing end labelling, and make use of the unsaturated uronic acid that is derived when obtaining GAGs through enzymatic depolymerisation. A hydrazide labelling of uronic acids was initially adopted, however due to concerns regarding selectivity and availability of hydrazide spin labels, an alternative Thiol-Ene Click (TEC) method was developed. TEC labelling of monosaccharides and unnatural amino acids was found to proceed efficiently under aqueous conditions and was monitored by NMR and HPLC. Preliminary studies in the TEC labelling of chondroitin sulfate disaccharides proved promising, however further optimisation is required for this method to be utilised in the study of protein-GAG interactions by NMR.