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Characterisation and regulation of SLC1 amino acid transporters in human intestinal epithelial cellsGray, Penney Amanda January 2002 (has links)
No description available.
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Balancing ammonia and alkalinity for nitrification at Walnut Creek Wastewater Treatment PlantWeidner, Austin David 12 September 2014 (has links)
The Walnut Creek Wastewater Treatment Plant in Austin, Texas, has recently experienced increasing influent ammonia concentrations. Nitrification, the biological process used to treat ammonia, consumes alkalinity, which makes it difficult to properly treat ammonia while still maintaining the pH above the required discharge level of pH 6. Operators have looked to the addition of chemicals to supplement alkalinity; one creative alkalinity source was CaCO₃ solids, which are generated by the lime-softening process at Davis Water Treatment Plant. In 2011, the utility began transferring solids to Walnut Creek and immediately noticed improvements in both the nitrification efficiency and the effluent pH. However, undissolved solids accumulated at Walnut Creek and had a detrimental effect on the biosolids treatment efficiency at Hornsby Bend Biosolids Management Plant. Ultimately the costs of the poor biosolids treatment forced the utility to examine an alternative alkalinity source. The objective of this thesis is to help Walnut Creek optimize the use of various alkalinity sources to find a long-term solution that will improve the alkalinity and ammonia balance for adequate nitrification. Analysis of the plant’s influent characteristics suggested that industrial users, especially the semiconductor industry, are major contributors of ammonia and sulfate to the wastewater. A theoretical modeling based on chemical equilibrium predicted that using the CaCO₃ solids would provide a maximum alkalinity benefit of 47 mg/L as CaCO₃. Experimental dissolution jar tests were conducted to verify the model predictions and estimate the kinetics of dissolution. Results from these tests showed no significant dissolution of CaCO₃, and that the solids remained unchanged throughout the test. These results indicate that CaCO₃ solids are not recommended to provide alkalinity at Walnut Creek. Finally, the use of Mg(OH)₂ for alkalinity was employed at Walnut Creek and allowed operators to reduce the blowers that provide aeration. To quantify this observation, bubbling column tests were conducted to measure differences in the oxygen transfer rate at various Mg(OH)₂ concentrations. However experimental results did not match the expectations, so future work is required. / text
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Expression and function of multidrug resistance-associated proteins (MRP) in human intestinePrime-Chapman, Hannah Margaret January 2002 (has links)
No description available.
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Estudo de ADME de candidatos a fármacos para o tratamento da leishmaniose visceral e tripanossomíase americana /Silva, Bruna Cristina Ulian. January 2019 (has links)
Orientador: Rosângela Gonçalves Peccinini / Resumo: Estudos precoces de ADME podem agilizar o processo de desenvolvimento de novos fármacos, selecionando os mais promissores para futuros estudos farmacocinéticos. Nesse sentido, e considerando a necessidade de novos tratamentos para a leishmaniose visceral e para a tripanossomíase americana, as moléculas LINS03006, LINS03011 e LINS03013 com ação sobre o Trypanosoma cruzi e a Leishmania infantum foram desenvolvidas por pesquisadores da UNIFESP/Diadema. O presente trabalho teve como objetivo realizar estudos físico-químicos e de ADME para a seleção das moléculas LINS mais promissoras para futuros estudos in vivo. Métodos analíticos e bioanalíticos por UHPLC/UV foram desenvolvidos para a quantificação dos compostos nos ensaios realizados. Foram realizados estudos de estabilidade química em diferentes pHs (1,2; 7,4 e 8,8), estabilidade metabólica em microssomos de rato e humano, estabilidade ex vivo, coeficientes de partição (log P) e permeabilidade em células Caco-2. Os compostos apresentaram estabilidade de até 24 horas em todos os pHs avaliados, levando à expectativa de que na administração oral não ocorrerá degradação decorrente do pH estomacal, sanguíneo e duodenal. O estudo em plasma de rato resultou, para todos os compostos, estabilidade em tempo suficiente – ao menos 6 horas – com expectativa de que ocorra efeito in vivo. Nos estudos de logP, os compostos apresentam características lipofílicas, favorecendo a permeabilidade e o clearance hepático. No ensaio de permeabilidade... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Early studies of ADME can speed up the development of new drugs, selecting the most promising for future pharmacokinetic studies. In this sense, and considering the need for new treatments for visceral leishmaniasis and american trypanosomiasis, the molecules LINS03006, LINS03011 and LINS03013 with action on Trypanosoma cruzi and Leishmania infantum were developed by researchers from UNIFESP/Diadema. The present work aimed to perform physical-chemical and ADME studies to select the most promising LINS molecules for future in vivo studies. Analytical and bioanalytical methods by UHPLC/UV were developed for the quantification of compounds in the assays performed. Chemical stability studies were performed at different pHs (1.2, 7.4 and 8.8), metabolic stability in rat and human microsomes, ex vivo stability, partition coefficients (log P) and permeability in Caco-2 cells. The compounds exhibited stability of up to 24 hours in all evaluated pHs, leading to the expectation that oral degradation will not occur due to stomach, blood and duodenal pH. The study in rat plasma resulted, for all compounds, stability in sufficient time - at least 6 hours - with the expectation that in vivo effect would occur. In logP studies, the compounds presented lipophilic characteristics, favoring permeability and hepatic clearance. In the permeability assay, the LINS compounds presented Papp > 5.0xE-06 cm/s, which can be classified as medium or high permeability, thus, there is an expectation of abs... (Complete abstract click electronic access below) / Mestre
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Phospholipids and Terpenes Enhance the Absorption of Polyphenolics in a Caco-2 Cell ModelCardona Ponce, Jorge 1983- 14 March 2013 (has links)
Anthocyanins are the most important class of water-soluble pigments responsible for
red to blue colors in various plants. Anthocyanins naturally occur in a broad range of plants
and studies have shown associations between fruit consumption and reduction of certain
diseases thought to be related to the presence of these and other polyphenolics. However,
anthocyanin absorption is fairly poor which hinders their potential to be utilized in the
human body.
Absorption of anthocyanins extracted from açaí puree and port wine was assessed.
Various combinations of terpenes and phospholipids were added to anthocyanins to
modulate and increase their transport within a model system. Açaí and port wine
anthocyanins were poorly transported in the absence of phospholipids and terpenes. The addition of terpenes and phospholipids significantly increased the transport of
anthocyanins. Additionally, the presence of phospholipids and terpenes did not
influence the way anthocyanins degraded over a 40 day period of time at three different
temperatures. Transport of anthocyanins was not dependent on dosage since absorption
results were similar at both concentrations of anthocyanins tested. Two methods to mix
anthocyanins, phospholipids, and terpenes were also assessed (Sonication and French
Press). Comparisons illustrated that both technologies created matrices that maintained
the properties of phospholipids and terpenes as transport enhancers.
Finally, a study to determine the efficacy of phospholipids and terpenes on a
different type of polyphenolic compound was assessed. Transport of gallic acid was
enhanced by the use of these agents that cemented the idea that phospholipids and
terpenes can enhance the transport of various types of polyphenolics.
The aiding effect of phospholipids and terpenes was well established and could
play an important role in future investigation in this field. Further research needs to be
conducted to reveal more information about the nature of these vesicles or associations
that phospholipids and terpenes may have with anthocyanins. In vivo studies need to be
considered to confirm these effects in rat models and, ideally, in humans. Nevertheless,
these findings open a new line of investigation that could harvest promising results for
the future of ingredient development for food products.
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Étude in vitro de la sensibilité de l'[alpha]-casozépine, décapeptide à activité benzodiazépine mimétique, à diverses protéases et peptidases du tractus gastro-intestinal. Étude comportementale chez le rat Wistar de l'activité anxiolytique des fragments F97 et F95 libérés par la pepsineBalandras, Frédérique Laurent, François Gaillard, Jean-Luc January 2008 (has links) (PDF)
Thèse de doctorat : Sciences Agronomiques : INPL : 2008. / Titre provenant de l'écran-titre.
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Phenolic Compounds of Sorghum, their Chemopreventive Properties and AbsorptionTaleon Alban, Victor Manuel 16 December 2013 (has links)
Sorghum contains many phenolic compounds which have potential antioxidant, anti-inflammatory, and chemopreventive properties as well as natural colorants in foods. Phenolic compounds of stalks, sheaths, leaves, glumes and grains from tan (ARTx631/RTx436), red (Tx2911) and purple (Tx3362) sorghum plants were characterized by UPLC-MS/MS. Antiproliferative properties of selected sorghum extracts were evaluated using HT-29 colon cancer cells and absorption of their polyphenolics was determined by a Caco-2 in vitro model system.
Phenolic acids, flavones, 3-deoxyanthocyanidins and chalcones were found in all plant components. Phenolic acids were predominant in the stalks, sheaths and grains of all sorghum types. Flavone glycosides were predominant in leaves, sheaths and stalks while flavone aglycones in glumes and grains. 3-Deoxyanthocyanidins and chalcones were mostly found in sheaths, leaves, glumes and grains of Tx2911 (red) and Tx3362 (purple) genotypes. Sorghum leaves showed high levels of flavone glycosides while glumes had high levels of flavones aglycones.
Glume extract of ATx631/RTx436 (tan) and Tx2911 genotypes had the strongest antiproliferation activity (IC_(50) = 85-178 µg/ml), these extracts had also the highest levels of flavone aglycones (19.6-49.8 mg/g). Absorption of flavones (30.4-42.3 %) was higher than 3-deoxyantocyanidins (1.4-11.3%), while absorption of methoxylated 3-deoxyanthocyanidins (11.3%) was higher than non-methoxylated 3-deoxyanthocyanidins (1.4 – 1.6 %). Flavones had high absorption compared to other sorghum phenolics suggesting that sorghum flavone aglycones are more bioavailable than other sorghum phenolic compounds. Consequently, sorghum glumes could be used as used as a source of phytochemicals to increase value of sorghum crop.
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Development of in vitro Chylomicron Assay Using Caco-2 CellsSun, Yuxi 01 December 2013 (has links) (PDF)
Dietary fats are mainly transported by the intestine in lipoproteins: chylomicrons (CMs) and very low density lipoproteins (VLDLs). Unfortunately, studies of the intestinal absorption of dietary fat have been hampered by the lack of an adequate in vitro model system. As an in vitro model Caco-2 cells are able to secrete lipoproteins. We investigated the possible factors that may affect the secretion of CMs through the ultracentrifugation technique. The dose-dependent effects of oleic acid, mono-olein, egg lecithin, collagen matrix, and the effect of cell differentiation on CM secretion were then tested. We found that oleic acid, lecithin, and cell differentiation are critical for CM secretion by Caco-2 cells. To further confirm that our optimal condition is, in fact, favorable for efficient CM production, we compared it with control groups. We observed that our condition led to more efficient CM secretion as determined by the TGs, ApoB, and TEM analysis.
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PRE-ABSORPTIVE METABOLISM OF CAROTENOIDSThakkar, Sagar 08 September 2009 (has links)
No description available.
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Bioacessibilidade, atividade antioxidante e antiproliferativa de compostos bioativos fenólicos de sucos de frutos da família Myrtaceae / Bioaccessibility, antioxidant and antiproliferative activity of bioactive phenolic compounds in juices from fruits of Myrtaceae familyBeteto, Flávia Maria 16 November 2015 (has links)
Diversos estudos com compostos fenólicos têm demonstrado os efeitos benéficos destas substâncias frente a diversas patologias, incluindo alguns tipos de câncer. Considerando que os polifenóis da dieta, não absorvidos, podem permanecer no trato gastrointestinal por um período prolongado, e as células do epitélio intestinal podem ser regularmente expostas a estes compostos, é importante avaliar seu potencial efeito benéfico no trato gastrointestinal. Entretanto, é necessário determinar como o processo de digestão afeta a estabilidade e propriedades químicas destes compostos. O objetivo deste estudo foi avaliar a bioacessibilidade dos polifenóis de sucos de frutas da família Myrtaceae: cagaita (Eugenia dysenterica DC), camu-camu (Myrciaria dubia Mc Vaugh) e jaboticaba (Myrciaria cauliflora B.), o efeito da digestão gastrintestinal in vitro sobre sua atividade antioxidante, e a ação dos polifenóis dos sucos digeridos sobre a proliferação, ciclo celular e apoptose em células Caco-2 de adenocarcinoma de cólon humano. A digestão simulada in vitro causou perdas de alguns compostos, tais como os derivados de cianidina encontrados na jaboticaba, possivelmente devido às condições do pH intestinal. No entanto, o conteúdo de ácido elágico livre aumentou em todos os sucos analisados, indicando a ocorrência de hidrólise durante o processo de digestão in vitro, liberando ácido elágico a partir dos elagitaninos. A atividade antioxidante dos polifenóis foi afetada de forma diferente pela digestão in vitro, de acordo com o suco, provavelmente relacionado à composição de polifenóis. Quanto à proliferação, ciclo celular e apoptose, os polifenóis a partir da fração bioacessível do camu-camu apresentou aproximadamente 30% de inibição da proliferação, seguido pela cagaita com 24%, ambos na maior concentração testada (50 µg EAG/mL). Jaboticaba não apresentou efeito inibitório nas concentrações testadas, entretanto os compostos fenólicos de todas as frações bioacessíveis (50 µg EAG/mL) apresentaram parada no ciclo celular na fase G2/M sem induzir apoptose nas células Caco-2. Os resultados sugerem que os polifenóis das Myrtaceae podem modular a proliferação nas células Caco-2 por bloqueio da progressão do ciclo celular na fase G2/M e assim oferecer efeitos benéficos para a saúde do trato gastrointestinal. / Several studies with phenolic compounds have shown the beneficial effects of these substances across various diseases, including some types of cancer. Considering that most of the polyphenols and their conjugates, unabsorbed, can remain in the lumen for a prolonged period, and epithelial cells lining the intestine are regularly exposed to these compounds, it is important to evaluate their potential beneficial effects in the gastrointestinal tract. However it is necessary to evaluate how the digestion process affects the stability and chemical properties of these compounds. The aims of this study were to evaluate the bioaccessibility of polyphenols in juices from Brazilian native fruits of the Myrtaceae family (cagaita, camu-camu and jaboticaba), the effect of in vitro gastrointestinal digestion on their antioxidant activity, and the action of polyphenols from digested juices on proliferation, cell cycle and apoptosis in human colon cancer Caco-2 cells. The results showed that in vitro gastrointestinal digestion caused losses of some polyphenols, such as cyanidins derivatives from jaboticaba, possibly due to the exposure to conditions of intestinal pH. However, contents of free ellagic acid increased in all the juices analyzed, indicating the occurrence of hydrolysis during in vitro digestion process, releasing ellagic acid from the ellagitannins. The antioxidant activity was affected for different forms by the in vitro digestion, demonstrating be related to individual components present in each sample and the mechanisms by which they act as antioxidants. Regarding the evaluation of proliferation, cell-cycle and apoptosis, polyphenols from bioaccessible fractions of camu-camu showed about 30% of inhibition of proliferation, followed by cagaita with 24%, both at the highest concentration tested (50 µg GAE/mL). Jaboticaba did not show inhibitory effect at the concentrations tested but the phenolic compounds of all bioaccessible fractions (50 µg GAE/mL) showed arrest in G2/M phase of cell-cycle without inducing apoptosis in the Caco-2 cells. Results suggest that Myrtaceae polyphenols may modulate the proliferation of Caco-2 cells by blocking the progression of cell-cycle at G2/M phase, providing beneficial effects to gastrointestinal health.
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