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Growth and progression in colorectal cancerHörkkö, T. (Tuomo) 21 November 2006 (has links)
Abstract
Colorectal cancer is the second most common malignancy in the Western World. The overall 5-year survival is still only 50–60%. Thus, better prognostic markers are needed to improve survival of the disease.
Most colorectal cancers develop from pre-existing adenomas including conventional, flat and serrated adenomas. The most important prognostic factors include tumour stage, histologic subtype and poor differentiation. The prognosis of colorectal cancer depends mainly on tumour stage. The growth of colorectal cancer is determined by cell proliferation, differentation and apoptosis. The progression of colorectal cancer is associated with the growth pattern of colorectal cancer and its invasive margin. Cancer cell budding means the presence of cells scattered in the stroma at the invasive margin, and is associated with β-catenin, an adhesion protein involved in the nuclear Wnt/β-catenin pathway. Hormones may be directly involved in the growth of a cancer, for example sex hormones play an important role in the development of most gynaecological cancers. The knowledge about the dependency of cancers on other hormones, such as thyroid hormones, is limited. This thesis focuses on factors affecting growth and prognosis in colorectal cancer.
Antibodies for Ki-67, caspase cleavage site for keratin 18, β-catenin and TRβ1 were used to determine their possible associations with colorectal cancer growth patterns and the characteristics of the invasive margin. Apoptosis and proliferation were decreased at the invasive margin, particularly in serrated adenocarcinomas. The invasive margin showed a presence of budding cell clusters in 24.0% of the cases and this predicted a very poor 5-year-survival (15.4%, P < 0.00001), but nuclear β-catenin accumulation did not predict budding. Thyroid hormone receptor TRβ1 was associated with polypoid growth, presence of KRAS mutations and also with a higher WHO histological grade and advanced Dukes' stage, and in in vitro analysis, thyroid hormone T3 had a modulatory effect on colorectal cancer cell protein synthesis and apoptosis.
In conclusion, the growth type of colorectal cancer, i.e. conventional polypoid, flat or serrated, has an association with the characteristics of the invasive margin. Budding margin is associated with poor prognosis in colorectal cancer, and could be utilised in diagnostic pathology. Association of TRβ1 expression with polypoid growth pattern and the presence of KRAS mutations suggest that abnormalities in thyroid hormone signalling involving TRβ1 play a role in the development of some types of colorectal adenocarcinomas.
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Improving Caco-2 cell permeability assay using phospholipid covered silica beadsFaradj, Lana January 2021 (has links)
The Caco-2 cell assay is widely used for in vitro permeability measurements. However, a draw back with the assay that this study will focus on improving, is compound adsorption to the plastic material. Lipophilic compounds such as Cyclosporin A and Peptide J, that will be used in this study, tend to bind to the plastic material in the assay. This can result in poor recovery and misleading permeability predictions. Bovine serum albumin (BSA) is an alternative used today to prevent this but is not always successful. The aim of this study is therefore to improve the Caco-2 permeability assay by adding phospholipid covered silica beads (PLB) to the basolateral chamber. The role of the PLB is to bind the compound of interest and decrease the amount of compound bound to the plastic material and thus better predict the permeability of the compound of interest. The PLB was produced using phosphatidylcholine and silica beads. Caco-2 cells were seeded and maintained for 21-29 days ahead of the experiment. PLB concentration of 20, 60 and 100 mg/ml were prepared. Samples were analyzed with HPLC-MSMS. The results showed that with increasing PLB concentration we had a significantly decrease in non-specific plastic binding resulting in reliable permeability predictions, concluding that the hypothesis was correct.
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Inhibiting Efflux With Novel Non-Ionic Surfactants: Rational Design Based on Vitamin E TPGSWempe, Michael F., Wright, Charles, Little, James L., Lightner, Janet W., Large, Shannon E., Caflisch, George B., Buchanan, Charles M., Rice, Peter J., Wacher, Vincent J., Ruble, Karen M., Edgar, Kevin J. 31 March 2009 (has links)
Tocopheryl Polyethylene Glycol Succinate 1000 (TPGS 1000) can inhibit P-glycoprotein (P-gp); TPGS 1000 was not originally designed to inhibit an efflux pump. Recent work from our laboratories demonstrated that TPGS activity has a rational PEG chain length dependency. In other recent work, inhibition mechanism was investigated and appears to be specific to the ATPase providing P-gp energy. Based on these observations, we commenced rational surface-active design. The current work summarizes new materials tested in a validated Caco-2 cell monolayer model; rhodamine 123 (10 μM) was used as the P-gp substrate. These results demonstrate that one may logically construct non-ionic surfactants with enhanced propensity to inhibit in vitro efflux. One new surfactant based inhibitor, Tocopheryl Polypropylene Glycol Succinate 1000 (TPPG 1000), approached cyclosporine (CsA) in its in vitro efflux inhibitory potency. Subsequently, TPPG 1000 was tested for its ability to enhance the bioavailability of raloxifene - an established P-gp substrate - in fasted male rats. Animals dosed with raloxifene and TPPG 1000 experienced an increase in raloxifene oral bioavailability versus a control group which received no inhibitor. These preliminary results demonstrate that one may prepare TPGS analogs that possess enhanced inhibitory potency in vitro and in vivo.
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Vývoj ligandů konstitutivního androstanového receptoru (CAR) / Development of novel Constitutive androstane receptor (CAR) ligandsDušek, Jan January 2019 (has links)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmacology and Toxicology Candidate Mgr. Jan Dušek Supervisor Prof. PharmDr. Petr Pávek, Ph.D. Title of Doctoral Thesis Development of novel Constitutive androstane receptor (CAR) ligands Constitutive androstane receptor is nowadays known as the established nuclear receptor that regulates the expression of several key cytochrome P450 enzymes, predominantly CYP3A4 and CYP2B6. Recently it has been shown that CAR has also essential role in the regulation of endogenous metabolism of glucose, lipids, cholesterole or bile acids. Simultaneously, this receptor is considered to have proliferative effect on human hepatocytes and protective effects against toxic and dietary damage of liver parenchyme. Given the possible therapeutic utilization of CAR, its therapeutic options are being intensively studied. Unfortunately, currently known ligands of human or mouse CAR are either poorly selective or indirect. The aim of my doctoral thesis was to find new ligands of mouse and human CAR, that would enable more detailed study of the receptor.
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NUEVAS ESTRATEGIAS PARA INCREMENTAR LA CALIDAD NUTRICIONAL DE PRODUCTOS DE PANADERÍA. EFECTO SOBRE EL CONTENIDO DE FITATOS Y LA BIODISPONIBILIDAD DE HIERRO EN CACO-2Sanz Penella, Juan Mario 30 March 2012 (has links)
Los productos de cereales con grano entero, en particular el pan, son fuentes de fibra dietética, vitaminas, minerales y compuestos fitoquímicos. Sin embargo, la biodisponibilidad de los minerales se afecta principalmente debido a la presencia de fitatos que reducen su absorción. El fitato se encuentra principalmente en los alimentos no procesados, pero puede ser degradado durante la germinación de las semillas o el procesado de alimentos. La hidrólisis del fitato a fosfatos de mio-inositol de menor grado de fosforilación es una manera de reducir su efecto negativo sobre la absorción de minerales. Muchas investigaciones han intentado reducir la cantidad de fitatos en los alimentos mediante diferentes procesos o adición de fitasas exógenas.
El objetivo principal de esta investigación fue incrementar el valor nutricional de los productos derivados de cereales a través de nuevas estrategias para la elaboración de productos de panadería de alta calidad, proporcionando más fibra dietética y una mayor biodisponibilidad de minerales. La inclusión de salvado de trigo en diferentes niveles y tamaño de partícula, con ?-amilasa y fitasa; el uso de bifidobacterias productoras de fitasa como nuevos iniciadores panarios; y la utilización de harina integral de amaranto como ingrediente nutritivo en panificación, fueron las estrategias propuestas para alcanzar el objetivo principal. Se evaluó la calidad nutricional, tecnológica y sensorial de los productos desarrollados. Asimismo, se estudió el efecto de la formulación en la relación molar fitato/mineral, la dializabilidad del hierro y la biosíntesis de ferritina en células Caco-2 como una medida de la absorción de este mineral. El salvado de trigo, en combinación con enzimas amilolíticas y fitasa, disminuyó el efecto negativo en la reología del producto y mejoró la hidrólisis de los fitatos. El uso de bifidobacterias productoras de fitasa (GRAS/PQS), tanto en proceso directo como indirecto, produjo panes con características tecnológicas y sensoriales similares a
los controles, pero con una cantidad menor de fitatos. Se consiguió una proporción
de compromiso de harina de amaranto en la formulación de pan para preservar la
calidad del producto e incrementar su valor nutricional. / Sanz Penella, JM. (2012). NUEVAS ESTRATEGIAS PARA INCREMENTAR LA CALIDAD NUTRICIONAL DE PRODUCTOS DE PANADERÍA. EFECTO SOBRE EL CONTENIDO DE FITATOS Y LA BIODISPONIBILIDAD DE HIERRO EN CACO-2 [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/15151
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A microfluidics-based in vitro model of the gastrointestinal human–microbe interfaceShah, Pranjul, Fritz, Joëlle V., Glaab, Enrico, Desai, Mahesh S., Greenhalgh, Kacy, Frachet, Audrey, Niegowska, Magdalena, Estes, Matthew, Jäger, Christian, Seguin-Devaux, Carole, Zenhausern, Frederic, Wilmes, Paul 11 May 2016 (has links)
Changes in the human gastrointestinal microbiome are associated with several diseases. To infer causality, experiments in representative models are essential, but widely used animal models exhibit limitations. Here we present a modular, microfluidics-based model (HuMiX, human-microbial crosstalk), which allows co-culture of human and microbial cells under conditions representative of the gastrointestinal human-microbe interface. We demonstrate the ability of HuMiX to recapitulate in vivo transcriptional, metabolic and immunological responses in human intestinal epithelial cells following their co-culture with the commensal Lactobacillus rhamnosus GG (LGG) grown under anaerobic conditions. In addition, we show that the co-culture of human epithelial cells with the obligate anaerobe Bacteroides caccae and LGG results in a transcriptional response, which is distinct from that of a co-culture solely comprising LGG. HuMiX facilitates investigations of host-microbe molecular interactions and provides insights into a range of fundamental research questions linking the gastrointestinal microbiome to human health and disease.
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Étude de l'oxydation de différents composés phénoliques par la laccase de Myceliophtora thermophila : application à la fonctionnalisation du chitosane / Study of different phenolic compounds oxidaton by laccase from Myceliophtora thermophila : application in the fuctionalization of chitosaneIssa, Nizar 17 July 2009 (has links)
La laccase de Myceliophtora thermophila oxyde certains acides hydroxycinnamiques avec formation éphémère d’intermédiaires de différentes couleurs avant que ceux-ci n’évoluent ensuite spontanément en polymères brun noir. Quand cette oxydation est effectuée en milieu biphasique (tampon phosphate pH 7,5 / acétate d’éthyle), une partie de ces intermédiaires colorés peut être récupérée dans la phase organique et ainsi soustraite à la polycondensation ultérieure. Dans le cas de l’acide férulique, on peut ainsi isoler une fraction colorée en jaune orangé surtout composée de dimères résultant de la condensation des semiquinones initialement formées. La synthèse de ces colorants peut être favorisée et le rendement amélioré en contrôlant la réaction par un ajout minimum régulé d’oxygène. Ces colorants conservent le pouvoir antioxydant de l’acide férulique parent mais à concentration élevée (100 à 200 mg/ml), ils présentent une cytotoxicité plus élevée vis-à-vis de cellules humaines normales (HUVEC) et cancéreuses (Caco-2) ce qui limite éventuellement leur intérêt comme colorants naturels. Les semi quinones de l’acide férulique ne forment pas de dimères mixtes, quand on effectue l’oxydation laccasique de cet acide en présence d’autres acides phénoliques car la laccase de M. thermophila effectue une oxydation séquencée en fonction de sa plus ou moins grande affinité pour les différents substrats mis en jeu. En présence d’un polyoside aminé insoluble comme le chitosane, les intermédiaires d’oxydation laccasique de différents composés phénoliques (acides férulique, sinapique, syringique et catéchine) réagissent avec les groupements NH2 pour former des liaisons de covalence et conduire ainsi à des chitosanes colorés doués de nouvelles propriétés dues au greffage d’entités phénoliques. Ces chitosanes fonctionnalisés conservent les propriétés filmogènes du chitosane natif mais en plus, forment des solutions plus visqueuses et sont devenus solubles en milieux acide et basique. Ils permettent la croissance de cellules HUVEC. Ils ont surtout acquis des propriétés antioxydantes et forment des films imperméables à l’oxygène ce qui laisse entrevoir de multiples applications intéressantes / The laccase of Myceliophtora thermophila oxidizes some hydroxycinnamic acids with ephemeral formation of intermediates of different colors before these evolve spontaneously in dark brown polymers. When this oxidation is performed in biphasique medium (phosphate buffer pH 7.5 and ethyl acetate), a part of these colored intermediates can be recovered in the organic phase and it can be subtracted from an ulterior polycondensation. In the case of ferulic acid, we could isolate an orange yellow fraction, which is especially composed of dimers resulting from the condensation of the semiquinones initially formed. The synthesis of these colorants can be enhanced and their yield can be improved by controlling the reaction through a regulated minimum addition of oxygen. They keep the antioxidant power of related ferulic acid, but in high concentration (from 100 to 200 mg/ml), their cytotoxicity toward the human normal cells (HUVEC) and cancerous one (Caco-2) is important and consequently, their interest is limited as natural colorants. The semiquinone of ferulic acid doesn't form any mixed dimers, when the laccase-catalysed ferulic acid oxidation is performed in the presence of other phenolic acids. This can be explained by the fact that laccase from M. thermophila performes a multioxidation in the function of its high or little affinity for the involved substrates. In presence of an insoluble amino polyoside as chitosan, the intermediates of laccase-catalysed oxidation of different phenolic compounds (ferulic, sinapic, syringic acids and catechin) react with its NH2 groups forming covalent liaisons. Actually, this type of link leads to colored chitosans endowed of news properties due to the grafting of phenolic entities. These functionalized chitosans keep the filmogens properties of the native one. Moreover, also it can form more viscous solutions and become soluble in acidic and basic medium. It can permit the growth of HUVEC cells. They especially acquired some antioxidant properties and formed impermeable films to the oxygen which highlights multiple interesting applications
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Use of fruit processing by-products for the development of cookies: physicochemical, nutritional, technological and sensory aspects / Aproveitamento de subprodutos do processamento de frutas para desenvolvimento de cookies: aspectos físico-químicos, nutricionais, tecnológicos e sensoriaisToledo, Nataly Maria Viva de 11 October 2018 (has links)
The present study aimed at characterizing pineapple, apple and melon by-products and evaluating their potential as an ingredient for the partial substitution of wheat flour in cookie formulations. The addition of fruit by-products contributed to rise the cookies fiber content. Melon by-product was prominent for its mineral content, whereas apple by-product presented more relevant results for phenolic compounds and antioxidant capacity (DPPH and ABTS). Such behaviors reflected in the cookie formulations. Eight phenolic compounds (vanillic acid, gallic acid, sinapic acid, salicylic acid, p-coumaric acid, catechin, epicatechin and rutin) were identified and quantified by HPLC in both the by-products and cookies. Regarding the antinutritional factors and mineral bioavailability, it was observed that the addition of fruit by-products in cookies reduced the contents of phytate and oxalate and promoted changes in calcium, iron and zinc bioavailability. Facing the technological aspects, it was observed that the use of by-products interfered in the color of the cookies, making them slightly darker and also weakened the gluten formed, promoting variations in diameter and expansion factor. On the other hand, it was observed that increasing concentrations of by-products led to higher values of hardness, making the cookies firmer and crunchier. In the sensory point of view, it was verified that the cookie with 15% of pineapple by-product demonstrated the highest acceptance, followed by cookies with 15% of apple by-product, control and 15% of melon by-product. By quantitative descriptive analysis (QDA), it was found that the addition of fruit by-products altered the sensory profile of the cookies. From the results obtained, it can be concluded that the fruit by-products are potential ingredients for cookie formulation, attributing to them specific physicochemical, technological, nutritional and sensory properties which can vary according to the by-products employed. / O presente estudo visou caracterizar subprodutos de abacaxi, maçã e melão e avaliar seu potencial como ingrediente para substituição parcial de farinha de trigo em formulações de biscoitos. A adição de subprodutos de frutas contribuiu para elevar o teor de fibras dos biscoitos. O subproduto de melão se destacou por seu conteúdo mineral, enquanto que o subproduto de maçã apresentou resultados mais relevantes para compostos fenólicos e capacidade antioxidante (DPPH e ABTS). Tais comportamentos se refletiram nas formulações de biscoitos. Oito compostos fenólicos (ácido vanílico, ácido gálico, ácido sinápico, ácido salicílico, ácido p-cumárico, catequina, epicatequina e rutina) foram identificados e quantificados por HPLC tanto nos subprodutos como nos biscoitos. Com relação aos fatores antinutricionais e biodisponibilidade mineral, observou-se que a adição de subprodutos de frutas em biscoitos diminuiu os teores de fitato e oxalato e promoveu mudanças na biodisponibilidade de cálcio, ferro e zinco. Frente aos aspectos tecnológicos, observou-se que o uso de subprodutos interferiu na cor dos biscoitos, tornando-os levemente mais escuros e também enfraqueceu a rede de glúten formada, promovendo variações do diâmetro e fator de expansão. Por outro lado, observou-se que quanto maior a concentração de subprodutos, maiores foram os valores de dureza (textura), sendo as amostras consideradas mais firmes e crocantes. Do ponto de vista sensorial, verificou-se que o biscoito com 15% de subproduto de abacaxi foi o que demonstrou maior aceitação, seguido pelos cookies com 15% de subproduto de maçã, controle e 15% de subproduto de melão. Por meio de análise descritiva quantitativa (ADQ), observou-se que a adição de subprodutos de frutas alterou o perfil sensorial dos biscoitos. A partir dos resultados obtidos, concluiu-se que os subprodutos de frutas se apresentam como potenciais ingredientes para formulações de cookies, atribuindo-lhes propriedades físico-químicas, tecnológicas, nutricionais e sensoriais específicas as quais podem variar de acordo com o subproduto empregado.
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Use of fruit processing by-products for the development of cookies: physicochemical, nutritional, technological and sensory aspects / Aproveitamento de subprodutos do processamento de frutas para desenvolvimento de cookies: aspectos físico-químicos, nutricionais, tecnológicos e sensoriaisNataly Maria Viva de Toledo 11 October 2018 (has links)
The present study aimed at characterizing pineapple, apple and melon by-products and evaluating their potential as an ingredient for the partial substitution of wheat flour in cookie formulations. The addition of fruit by-products contributed to rise the cookies fiber content. Melon by-product was prominent for its mineral content, whereas apple by-product presented more relevant results for phenolic compounds and antioxidant capacity (DPPH and ABTS). Such behaviors reflected in the cookie formulations. Eight phenolic compounds (vanillic acid, gallic acid, sinapic acid, salicylic acid, p-coumaric acid, catechin, epicatechin and rutin) were identified and quantified by HPLC in both the by-products and cookies. Regarding the antinutritional factors and mineral bioavailability, it was observed that the addition of fruit by-products in cookies reduced the contents of phytate and oxalate and promoted changes in calcium, iron and zinc bioavailability. Facing the technological aspects, it was observed that the use of by-products interfered in the color of the cookies, making them slightly darker and also weakened the gluten formed, promoting variations in diameter and expansion factor. On the other hand, it was observed that increasing concentrations of by-products led to higher values of hardness, making the cookies firmer and crunchier. In the sensory point of view, it was verified that the cookie with 15% of pineapple by-product demonstrated the highest acceptance, followed by cookies with 15% of apple by-product, control and 15% of melon by-product. By quantitative descriptive analysis (QDA), it was found that the addition of fruit by-products altered the sensory profile of the cookies. From the results obtained, it can be concluded that the fruit by-products are potential ingredients for cookie formulation, attributing to them specific physicochemical, technological, nutritional and sensory properties which can vary according to the by-products employed. / O presente estudo visou caracterizar subprodutos de abacaxi, maçã e melão e avaliar seu potencial como ingrediente para substituição parcial de farinha de trigo em formulações de biscoitos. A adição de subprodutos de frutas contribuiu para elevar o teor de fibras dos biscoitos. O subproduto de melão se destacou por seu conteúdo mineral, enquanto que o subproduto de maçã apresentou resultados mais relevantes para compostos fenólicos e capacidade antioxidante (DPPH e ABTS). Tais comportamentos se refletiram nas formulações de biscoitos. Oito compostos fenólicos (ácido vanílico, ácido gálico, ácido sinápico, ácido salicílico, ácido p-cumárico, catequina, epicatequina e rutina) foram identificados e quantificados por HPLC tanto nos subprodutos como nos biscoitos. Com relação aos fatores antinutricionais e biodisponibilidade mineral, observou-se que a adição de subprodutos de frutas em biscoitos diminuiu os teores de fitato e oxalato e promoveu mudanças na biodisponibilidade de cálcio, ferro e zinco. Frente aos aspectos tecnológicos, observou-se que o uso de subprodutos interferiu na cor dos biscoitos, tornando-os levemente mais escuros e também enfraqueceu a rede de glúten formada, promovendo variações do diâmetro e fator de expansão. Por outro lado, observou-se que quanto maior a concentração de subprodutos, maiores foram os valores de dureza (textura), sendo as amostras consideradas mais firmes e crocantes. Do ponto de vista sensorial, verificou-se que o biscoito com 15% de subproduto de abacaxi foi o que demonstrou maior aceitação, seguido pelos cookies com 15% de subproduto de maçã, controle e 15% de subproduto de melão. Por meio de análise descritiva quantitativa (ADQ), observou-se que a adição de subprodutos de frutas alterou o perfil sensorial dos biscoitos. A partir dos resultados obtidos, concluiu-se que os subprodutos de frutas se apresentam como potenciais ingredientes para formulações de cookies, atribuindo-lhes propriedades físico-químicas, tecnológicas, nutricionais e sensoriais específicas as quais podem variar de acordo com o subproduto empregado.
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ASSESSMENT OF BOVINE VASCULAR SEROTONIN RECEPTOR POPULATIONS AND TRANSPORT OF ERGOT ALKALOIDS IN THE SMALL INTESTINESnider, Miriam A. 01 January 2017 (has links)
Prior work using a contractility bioassay determined that the serotonin (5-HT) receptor subtype 5-HT2A is present in bovine lateral saphenous veins and plays a role in ergot alkaloid-induced vascular contraction in steers grazing endophyte-infected (Epichloë coenophiala) tall fescue (Lolium arundinaceum). A study was conducted to determine what 5-HT receptors are involved in vasoconstriction of bovine gut vasculature. The findings of this study indicate that 5-HT2A is present and may play a role in ergot alkaloid induced vasoconstriction. A second study was conducted to determine if ergot alkaloids were transported in the small intestine. The active transporter, peptide transporter 1 (PepT1), was evaluated for its role in the transport of various concentrations of ergot alkaloids across Caco-2 cell monolayers. Results indicate that CEPH, ERT, EXT, and LSA do move across Caco-2 cell monolayers, but appear to utilize PepT1 at larger concentrations. Overall, the demonstrated presence of 5-HT2A receptors in the bovine gut vasculature established a potential for vascular interference by ergot alkaloids entering the bloodstream through transepithelial absorption.
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