Background: Contribution of dietary sources to vitamin D status is not clearly known. Some studies have shown that dietary intake of certain vitamin D rich foods had a significant positive influence on serum 25-hydroxyvitamin D [25(OH)D] concentrations, whereas other studies have shown no effect. Although sunlight exposure is a major source of circulating serum 25(OH)D, children and adolescents have been advised on the dangers of sun exposure. Diet may therefore be an important contributor of circulating serum 25(OH)D in absence of or reduced sunlight exposure. Objective: The aim of this study was to determine whether serum 25(OH)D concentrations were associated with any specific dietary patterns in US children and adolescents using assay-adjusted serum 25(OH)D data from National Health and Nutrition Examination Survey (NHANES) 2003-2004 and 2005-2006. Methods: Data from 2 cycles of the NHANES 2003-2004 and 2005-2006 for individuals aged 2 to ≤19 y, were used to study the association between dietary patterns and serum 25(OH)D. Dietary patterns were established using factor analysis based on food-frequency questionnaire data. Eigenvalues and Scree plot were used to derive 2 major principal factors. They were labeled as High Fat Low Vegetable (HFLV) and Prudent dietary patterns. Results: Serum 25(OH)D was significantly lower in HFLV dietary pattern group compared to Prudent dietary pattern group (25.1 vs 27.0 ng/mL; P=0.001). The highest serum 25(OH)D concentrations for all subjects were in the low-intake HFLV group or medium and high-intake Prudent groups (P=0.003 and P=0.012, respectively). In multivariate adjusted analysis, children with higher Prudent dietary contribution scores to overall diet showed a significant positive relation with serum 25(OH)D (β=62.01, P=0.016). When data were stratified by sex, a significant positive relation was observed in girls who consumed the Prudent diet (β=86.34, P=0.014) and a significant negative relation was observed in girls who consumed the HFLV diet (β=-84.32, P=0.022). Conclusion: Overall, serum 25(OH)D concentrations were associated with Prudent dietary pattern but not with HFLV dietary pattern in US children and adolescents. When stratified by sex, the relation between dietary patterns and serum 25(OH)D was confined to only girls. Children consuming HFLV pattern diet may benefit from vitamin D supplementation and sunlight exposure (outdoor activities), and should be encouraged to consume more vitamin D fortified foods.

This thesis presents a study on the enhancement of CHO cell growth by Yeast extract, Yeastolate, and Primatone fractions obtained by dead-end ultrafiltration. The total solid, peptide contents, antioxidant capacity and hydrophobicity of the fractions were evaluated. The objective of this project was to evaluate the potential of sequential ultrafiltration as an effective, simple and economical method for the identification of CHO cell growth enhancement components in yeast extract and yeastolate (primatone). The fractionation by sequential ultrafiltration (50 kDa membrane, 3 kDa membrane and 1 kDa membrane) of yeast extract (YE), yeastolate (YET), and primatone (PRI) showed different fouling and fractionation behaviour. Significant fouling was observed with the 50 kDa and 3 kDa membrane while negligible fouling was observed with the 1 kDa membrane. Similar and more significant fouling was observed with the 50 kDa membrane and for YE and PRI in comparison to YET. In contrast, more fouling was observed during the ultrafiltration with the 3kDa MWCO and for YE and YET in comparison to PRI. Finally a relatively constant permeate flux was obtained with the 1 kDa membrane, with PRI the highest and YET the lowest permeate flux. Different total peptide contents were present in the three feeds, 410, 327 and 300 mmol Phe-Gly equivalent/ g total solids for YE, PRI and YET respectively. In spite of different feed equivalent Phe-Gly, all three feeds contained a similar amount of equivalent Phe-Gly with molecular weight larger than 50 kDa, 15-19% of the initial feed stream. This was similar amount to the total solids content. The total peptide content of the retentate obtained for the 3kDa filtration indicated that YE and YET contained ~ 20% of equivalent Phe-Gly larger than 3 kDa but smaller than 50kDa. In contrast, PRI contained only 6% of equivalent Phe-Gly with such molecular weight. The retentate of the 1kDa filtration contained 55% of the feed equivalent Phe-Gly compared to 47% for YE and 38% for YET (p< 0.05). All three feeds have similar total peptide content smaller than 1 kDa. For any given feed, the equivalent Phe-Gly was larger than 1 kDa but smaller than 3 kDa predominated. The total peptide content profile according to size coincides with the total solids distribution for all three feed types. This is the first study that reports on the total peptide content for YE, YET, and PRI subjected to ultrafiltration fractionation. All three feeds and their fractions when freeze-dried had similar antioxidant capacity estimated by the FCR (Folin-Ciocalteu reagent) assay, ~ 40-50 mg Trolox/g sample. The bioactivity of feed and fractions was measured as cell density for CHO (beta-IFN producers) in basal medium supplemented with a combination of the crude non-fractionated feed material and a specific fraction and grown in T25 flasks. PRI showed a similar growth enhancement effect for all fractions when compared to a culture supplemented with the crude non-fractionated. YE showed no growth enhancement for any of the fractions when compared to a culture supplemented with the crude non-fractionated YE. This observation need to be confirmed as a culture supplemented with the crude non-fractionated YE showed a very high growth stimulating effect which was much higher than PRI and YET at the same concentration. Finally, YET 3kDa retentate fraction displayed a 50 % growth enhancement effect. In conclusion, the fractions obtained from the two non-animal protein hydrolysates considered in this study, YE and YET showed limited CHO cell growth enhancement effect when compared to the non-fractionated material. Only the YET 3kDa retentate fraction displayed a good CHO cell growth enhancement effect. YET 3kDa represent an attractive serum substitute for its use in culturing CHO cells. PRI, an animal derived protein hydrolysate showed the best growth enhancement effect for all fractions produced in this study. These results suggest that YET has high potential as a media additive for the development of serum-free media which can promote cell growth and, in the future this work can contribute in production of therapeutic proteins markets.

Fair division is the problem of dividing one or several goods among a set of agents in a way that satisfies a suitable fairness criterion. Traditionally studied in economics, philosophy, and political science, fair division has drawn a lot of attention from the multiagent systems community, since this field is strongly concerned about how a surplus (or a cost) should be divided among a group of agents. Arguably, the Shapley value is the single most important contribution to the problem of fair division. It assigns to each agent a share of the resource equal to the expected marginal contribution of that agent. Thus, it is implicitly assumed that individual marginal contributions can be objectively computed. In this thesis, we propose a game-theoretic model for sharing a joint reward when the quality of individual contributions is subjective. In detail, we consider scenarios where a group has been formed and has accomplished a task for which it is granted a reward, which must be shared among the group members. After observing the contribution of the peers in accomplishing the task, each agent is asked to provide evaluations for the others. Mainly to facilitate the sharing process, agents can also be requested to provide predictions about how their peers are evaluated. These subjective opinions are elicited and aggregated by a central, trusted entity, called the mechanism, which is also responsible for sharing the reward based exclusively on the received opinions. Besides the formal game-theoretic model for sharing rewards based on subjective opinions, we propose three different mechanisms in this thesis. Our first mechanism, the peer-evaluation mechanism, divides the reward proportionally to the evaluations received by the agents. We show that this mechanism is fair, budget-balanced, individually rational, and strategy-proof, but that it can be collusion-prone. Our second mechanism, the peer-prediction mechanism, shares the reward by considering two aspects: the evaluations received by the agents and their truth-telling scores. To compute these scores, this mechanism uses a strictly proper scoring rule. Under the assumption that agents are Bayesian decision-makers, we show that this mechanism is weakly budget-balanced, individually rational, and incentive-compatible. Further, we present approaches that guarantee the mechanism to be collusion-resistant and fair. Our last mechanism, the BTS mechanism, is the only one to elicit both evaluations and predictions from the agents. It considers the evaluations received by the agents and their truth-telling scores when sharing the reward. For computing the scores, it uses the Bayesian truth serum method, a powerful scoring method based on the surprisingly common criterion. Under the assumptions that agents are Bayesian decision-makers, and that the population of agents is sufficiently large so that a single evaluation cannot significantly affect the empirical distribution of evaluations, we show that this mechanism is incentive-compatible, budget-balanced, individually rational, and fair.

Verapamil is a commonly used medicine for the treatment of supraventricular arrhythmias, angina and hypertension. Recently, some newly developed applications of Verapamil, such as treating hypomania and chemotherapy for cancers, have been reported. Thus, monitoring the concentration of Verapamil accurately is very important. The major clinical analytical methods of Verapamil concentration determination are high performance liquid chromatography (HPLC) with UV or with fluorescence detector. However, these analytical methods have some disadvantages, like expensive instruments, complex operation, and time-consuming etc. The chemical structure and properties of Verapamil are very stable. The preliminary result of electrochemical analysis doesn¡¦t show any electrochemical activity. In this study, we developed an innovative ozone pre-treatment method to oxidize Verapamil to the smaller molecules and change its structure. Verapamil have excellent electrochemical activity after ozone pre-treatment. The spectroscopy and mass spectrometry show the changes of Verapamil structure. The products of Verapamil treated with ozone are also predicted by mass spectrometry. The gold nanoelectrode ensemble electrodes (GNEE) are used as working electrode for its good catalytic activity of electrochemical reaction, high sensitivity and high selectivity. The overall experimental framework of this study is microchip with GNEE working electrode accompanied by cyclic voltammetry, an electrochemical analytical instrument. Compared with traditional analytical methods, the system has some advantages such as small size, micro sample volume, easy operation, rapid detection and low cost. The limit concentration of Verapamil solution for stable detection in the system is 10 ng/mL. A linear dynamic range with a high correlation factor from 10 ng/mL to 100 £gg/mL was obtained. For the analysis of serum sample, Verapamil present excellent electrochemical activity at 1 ng/mL. A linear dynamic range with a high correlation factor from 1 ng/mL to 100 £gg/mLwas obtained. According to the results, our system for clinical Verapmil concentration analysis has the feasibility of the practical application.

We have previously used a two-dimensional fluorescence difference gel electrophoresis protein expression with matrix-assisted laser desorption ionization of mass spectrometry to identify the serum proteomic profiles before and after the Tai Chi exercise in normal adults (Yang & Chang, et al. Clin Chem 56:127, 2010). However, the high abundant serum proteins in seyal samples might interfere the discovery of low abundance proteins in two-dimensional electrophoresis, but these low abundant proteins may play an important role on human physiology. Therefore, we looked for another way to resolve this complex issue. After multiple attempts, we chose a commercial affinity column to exclude 14 kinds of high-abundance proteins before analyses of serum proteomic displays. This column could be fit into a fast liquid chromatography separation of purified proteins and eluted for low abundant proteins. The low abundant proteins were first expressed by one-dimensional gel electrophoresis of proteins followed by a series of gel cut down for in-gel digestion by trypsin and subject to nano-liquid chromatography with electrospray ionization tandem mass spectrometry analysis (nano-LC ESI MS/MS ). The results obtained by software analysis were subject to its functional pathways analysis. We analysed 3 comparisons of the protein displays including differences between normal adults before and after exercise, differences of normal adults and diabetic patients before and after exercise. Experiments were next performed to validate the most significant difference of proteins between each category by enzyme-linked immunoassay. Results showed that dipeptidyl peptidase 4 (DPP4) and neutrophil gelatinase-associated lipocalin (NGAL) proteins were significantly higher in diabetic patients than in normal adults ( P values were 0.011 and less than 0.001), while the prolactin-inducible protein (PIP) was higher in normal adults than in diabetic patients after exercise (P value of 0.042). To our knowledge, decrease of DPP4 in type 2 diabetes has been shown to reduce blood sugar and improve the immunity; and NGAL has been confirmed to be an indicator for early diagnosis of acute kidney injury. Therefore, we have identified certain functional proteomic markers in normal and diabetic patients after Tai Chi exercise. This study model with exclusion of high-abundance serum proteins is a useful mode for identifying immune and metabolic marker with and without.

Assessment of gastrointestinal permeability in vivo is considered a suitable method for the evaluation of gastrointestinal mucosal integrity. Probes commonly used include lactulose (L) and rhamnose (R) for the assessment of intestinal permeability, xylose (X) and 3-O-methylglucose (M) for the evaluation of intestinal absorptive capacity, and sucrose (S) for the assessment of gastric permeability. Traditionally, various methods have been used to quantify these markers in the urine after orogastric administration. However, urine collection is difficult and uncomfortable. A protocol based on the analysis of blood samples would be easier to perform. Thus, the aim of the first part of this project was to develop and validate a new gas chromatography-mass spectrometry (GC-MS) method for the quantification of five sugar probes in canine serum. The method was sensitive, accurate, precise, and reproducible for the simultaneous quantification of 5 sugar probes in serum. The aim of the second part of this project was to assess the kinetic profiles of these 5 sugar probes in serum after orogastric administration in dogs and to determine the optimal time point for sample collection. Dogs received a solution containing L (10 g/L), R (10 g/L), X (10 g/L), M (5 g/L), and S (40 g/L) by orogastric intubation. Baseline blood samples were collected. Subsequent timed blood samples were taken for a 24 hours period. Significant changes in serum concentrations of all 5 sugars were detected after administration of the test dose (p<0.0001 for all 5 probes). Serum concentrations of L and R were significantly different from baseline concentrations from 90 to 240 and from 60 to 300 min post dosing respectively, and those of X, M, and S were significantly different from 30 to 240 min after dosing (p<0.05 for all 5 probes). Variations of the mean sugar concentrations of all dogs at 90, 120, and 180 minutes were analyzed using a Kruskal-Wallis test. Based on the results, only two blood samples, one taken at baseline and a second sample obtained between 90 and 180 after dosing, appear to be sufficient for assessment of intestinal permeability and mucosal absorptive capacity using these sugar probes.

none

In this study, a methodology for separation of chiral molecules, by using enhanced ultrafiltration system was developed. Benzoin was the model chiral molecule studied. In the scope of developing this methodology, some parameters were investigated in the preliminary ultrafiltration experiments in order to set the operation conditions for enhanced ultrafiltration experiments. Due to the slight solubility of benzoin in pure water, 15% (v/v) Polyethylene glycol (PEG 400) and 30 % (v/v) Dimethyl sulfoxide (DMSO) were selected as cosolvents. Because of the high retention capacity of RC-10000 Da membranes for benzoin, a membrane saturation strategy was developed. In polymer enhanced ultrafiltration (PEUF) experiments bovine serum albumin (BSA) was used as ligand. Effects of ligand concentration and pH on total benzoin retention and on enantiomeric excess (ee %) were investigated. Benzoin concentration was almost kept constant at ~10 ppm and ~50 ppm for 15% (v/v) PEG 400 and 30 % (v/v) DMSO cosolvents, respectively. It was observed that the increase either in pH or in BSA concentration yielded an increase in total benzoin retention. In 15% (v/v) PEG 400-water, with BSA concentration of 10000 ppm, at pH 10, total benzoin retention reached to 48.7%. For this cosolvent, at different pH values and at different BSA concentrations, all ee % values were about or less than 10%. When 50000 ppm BSA was dissolved in 30 % (v/v) DMSO-water, total benzoin retention increased to 41.3% at pH 10 and ee % reached 16.7 % at pH 11. In enzyme enhanced ultrafiltration (EEUF) experiments, specific to benzoin, apo form of Benzaldehyde Lyase (BAL, E.C. 4.1.2.38) was used as ligand. These experiments were performed with constant ~ 10 ppm benzoin concentration in only 15% (v/v) PEG 400 &ndash / water solvent. Effect of BAL concentration on total benzoin retention and ee% was investigated. It was found that / for all the studied BAL concentrations in the range of 650- 1936 ppm total benzoin retention and ee % were kept almost constant at ~75% and ~60%, respectively.

No description available.

Thesis (Ph. D.)--University of Washington, 2003. / Vita. Includes bibliographical references (leaves 96-101).