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Extracellular Matrix from Whole Porcine Heart Decellularization for Cardiac Tissue EngineeringMomtahan, Nima 01 March 2016 (has links)
Heart failure is one of the leading causes of death in the United States. Every year in the United States, more than 800,000 people are diagnosed with heart failure and more than 375,000 people die from heart disease. Current therapies such as heart transplants and bioartificial hearts are helpful, but not optimal. Decellularization of porcine whole hearts followed by recellularization with patient-specific human cells may provide the ultimate solution for patients with heart failure. Great progress has been made in the development of efficient processes for decellularization, and the design of automated bioreactors. In this study, the decellularization of porcine hearts was accomplished in 24 h with only 6 h of sodium dodecyl sulfate (SDS) exposure and 98% DNA removal. Automatically controlling the pressure during decellularization reduced the detergent exposure time while still completely removing immunogenic cell debris. Stimulation of macrophages was greatly reduced when comparing native tissue samples to the processed ECM. Complete cell removal was confirmed by analysis of DNA content. General collagen and elastin preservation was demonstrated by SEM and histology. The compression elastic modulus of the ECM after decellularization was lower than native at low strains but there was no significant difference at high strains. Polyurethane casts of the vasculature of native and decellularized hearts demonstrated that the microvasculature network was preserved after decellularization. A static blood thrombosis assay using bovine blood was also developed. A perfusion bioreactor was designed and right ventricle of the decellularized hearts were recellularized with human endothelial cells and cardiac fibroblasts. An effective, reliable, and relatively inexpensive assay based on human blood hemolysis was developed for determining the remaining cytotoxicity of the cECM and the results were consistent with a standard live/dead assay using MS1 endothelial cells incubated with the cECM. Samples from the left ventricle of the hearts were prepared with 300 µm thickness, mounted on 10 mm round glass coverslips. Human induced pluripotent stem cells were differentiated into cardiomyocytes (CMs) and 4 days after differentiation, cardiac progenitors were seeded onto the decellularized cardiac slices. After 10 days, the tissues started to beat spontaneously. Immunofluorescence images showed confluent coverage of CMs on the decellularized slices and the effect of the scaffold was evident in the arrangement of the CMs in the direction of fibers. This study demonstrated the biocompatibility of decellularized porcine hearts with human CMs and the potential of these scaffolds for cardiac tissue engineering. Further studies can be directed toward 3D perfusion recellularization of the hearts and improving repopulation of the scaffolds with various cell types as well as adding mechanical and electrical stimulations to obtain more mature CMs.
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Polímeros de impressão molecular para extração seletiva de drogas em matrizes biológicas e determinação por LC-MS /MS e MS/MS / Molecularly imprinted polymer for selective extraction of drugs in biological matrices by LC-MS/MS e MS/MSFernandes, Raquel Maria Trindade, 1979- 22 August 2018 (has links)
Orientador: Marcos Nogueira Eberlin / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-22T00:48:57Z (GMT). No. of bitstreams: 1
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Previous issue date: 2012 / Resumo: O presente trabalho descreve a utilização de polímeros de impressão molecular (MIP) no preparo de amostra para a extração seletiva de fármacos em matrizes biológicas com determinação por LC-MS/MS e MS/MS. Inicialmente foi sintetizado e caracterizado um MIP seletivo a omeprazol, sendo o mesmo empregado na extração com fase sólida molecularmente impressa (MISPE) de omeprazol em amostras de plasma humano, seguido de determinação por LC-MS/MS. A metodologia foi validada por meio do estudo dos parâmetros: precisão (repetibilidade e precisão intermediária), exatidão (recuperação), curva analítica, intervalo de linearidade, limite de detecção ¿ LD e limite de quantificação ¿ LQ, e seletividade. O limite de quantificação obtido foi de 5 ng mL. Posteriormente, foi sintetizado e caracterizado um MIP seletivo a cocaína, sendo este empregado na extração em fase sólida molecularmente impressa (MISPE) online de cocaína em amostras de urina de usuários de drogas, seguido da quantificação por MS/MS. O limite de quantificação obtido foi de 10 ng mL. A seletividade do método foi avaliada pelo estudo de adsorção de metabólitos (benzoilecgonina e cocaetileno) e interferente (lidocaína) pelo polímero sintetizado e posterior determinação por MS/MS. / Abstract: The present work describes the applications of molecularly imprinted polymers (MIP) in sample preparation for the selective extraction of drugs in biological matrices by LC-MS/MS and MS/MS. Initially a MIP selective for omeprazolewas synthesized and characterized. It was used in molecularly imprinted solid phase extraction (MISPE) of omeprazole from human plasma samples, followed by LC-MS/MS determination. The methodology was validated by studying the parameters: precision (repeatability and intermediate precision), accuracy (recovery), calibration curve, linear range, detection limit - LOD and quantification limit - LOQ, and selectivity. The quantification limit was 5 ng ml. Subsequentlya MIP selective for cocaine was synthesized and characterizedwhich was used in online molecularly imprinted solid phase extraction (MISPE) for cocaine in urine samples of drug users, followed by quantification by MS / MS. The quantification limit was 10 ng mL. The selectivity of the method was evaluated by studying the adsorption of metabolites (benzoylecgonine and cocaethylene) and an interferent (lidocaine) by the synthesized polymer with subsequent determination by MS / MS. / Doutorado / Quimica Analitica / Doutora em Ciências
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Proposição de metodologia para estudo de uridina 5'-trifosfato trissódica e citidina 5'-monosfato dissódica e derivados em matriz biológica durante neuropatias periféricas / Proposition methodology for uridine 5'-triphosphate study trissódica and cytidine disodium 5'- monosfato and derivatives in biological matrix for peripheral neuropathiesSuchmacher Neto, Mendel January 2015 (has links)
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Previous issue date: 2015 / Fundação Oswaldo Cruz. Instituto de Tecnologia em Fármacos/Farmanguinhos. Rio de Janeiro, RJ, Brasil. / Uridina 5'-trifosfato trissódica (UTPt) e citidina 5'-monofosfato dissódica (CMPd) são nucleotídeos pirimidínicos do ácido nucleico. Eficácia e segurança de fármacos baseados na UTPt e CMPd, usados no tratamento para neuropatias periféricas já foram estudadas, no entanto informações sobre farmacocinética desses fármacos ainda não são conhecidas. O objetivo deste estudo foi propor metodologias para quantificar UTPt e CMPd em matrizes biológicas, baseando-se numa revisão sistemática da literatura. Levando em consideração que a biodisponibilidade das pirimidinas, durante as neuropatias periféricas é diferente da observada em voluntários sadios, os dados disponíveis acerca das concentrações plasmáticas do UTPt e CMPd não devem ser usados para estimar a dose de fármacos baseados nessas pirimidinas. Para diferenciar pirimidinas endógenas e exógenas em matrizes biológicas, estas últimas devem ser marcadas, antes da administração, com material radioativo tais como trício [3H] ou carbono 14 [14C]. Além disso, a cromatografia líquida de alta performance é a técnica mais aplicada para identificação e quantificação de pirimidinas radioativas. Nós concluímos que a radiomarcação de UTPt e CMPd, seguida de separação cromatográfica e detecção por UV e cintilografia líquida, seria uma metodologia factível para estudos de detecção e quantificação de derivados de UTPt e CMPd em matriz biológica / Pyrimidines uridine 5'-triphosphate trisodium (UTPt) and cytidine 5'-monophosphate disodium (CMPd) are standard nucleosides which make up nucleic acids. Efficacy and safety from UTPt and CMPd based drugs on peripheral
neuropathies has already been studied. However, information regarding pharmacokinetics of UTPt and CMPd based drugs during pathological condition remains unknown. The aim of this study was to propose methodologies to quantify
UTPt and CMPd in biological matrices, based on a systematic literature review. Concerning that the bioavailability of pyrimidines during peripheral neuropathies is different of observed in healthy volunteers, the available data regarding plasmatic levels of UTPt and CMPd should not be used to estimate the dose of UTPt and CMPd based drugs. Furthermore, to differentiate endogenous and exogenous
pyrimidines in biological matrices the exogenous pyrimidines must be labeled with
[3H] or [14C] before administration. Next, high-performance liquid chromatography
(HPLC) has been the most applied technique for identification and quantitation of radiolabeled pyrimidines. We concluded that UTPt and CMPd radiolabelling, followed by chromatographic separation and detection by UV and liquid scintigraphy, is a feasible methodology for detection and quantitation of UTPt and CMPd derivatives in biological matrices.
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Développement d’un couplage de chromatographie en phase supercritique et spectrométrie de masse pour l’analyse de substances naturelles / Development of supercritical fluid chromatography coupled to mass spectrometry for natural compounds analysisMéjean, Marie 17 October 2014 (has links)
L’objectif de ce projet doctoral a été de coupler la chromatographie en phase supercritique (SFC) avec un spectromètre de masse haute résolution pour l’analyse de substances naturelles apolaires. La SFC est une technique dite « verte » contrairement à la chromatographie liquide en phase normale (NPLC), très consommatrice de solvants organiques toxiques pour l’environnement, puisque la phase mobile est principalement constituée de CO2. Le CO2 ayant une faible viscosité, cela implique une diffusivité, des débits élevés et des temps d’analyse courts. Notre attention a été focalisée sur des molécules apolaires : les lipides. Le but était de mettre au point des dosages dans des matrices alimentaires et biologiques et de débuter une approche lipidomique d’étude de la maladie de Parkinson. La première partie a été dédiée au développement du système SFC avec une détection UV, prêté par le constructeur Agilent Technologies. La première étude s’est portée sur 6 composés de la famille des vitamines A. Une phase d’optimisation a été réalisée afin d’obtenir une séparation satisfaisante des composés, en testant différents paramètres chromatographiques comme le type de phase stationnaire ou encore la composition de la phase mobile, afin d’obtenir une résolution optimale. Ensuite, des études de linéarité et de répétabilité ont été réalisées et des limites de détection et de quantification ont été déterminées afin d’obtenir une méthode fiable et robuste. Une deuxième partie a concerné la mise en place du couplage entre la SFC et un spectromètre de masse de type quadripôle-temps de vol (Q-TOF), afin d’améliorer la spécificité et la sensibilité des analyses. Différentes sources d’ionisation ont été utilisées : ESI, APCI et APPI. Chacune des sources présente des modes d’ionisation différents, qui permettent de pouvoir balayer une large gamme de polarité des analytes. Nous avons choisi 8 dérivés de la vitamine E, composés apolaires pour lesquels la SFC paraît être la technique d’analyse idéale. La séparation de ces composés a été optimisée de façon à obtenir une bonne résolution chromatographique et un temps d’analyse minimal. L’ionisation des composés est réalisée avec les 3 sources disponibles en faisant varier les paramètres de sources ou encore le solvant « make-up », de façon à obtenir une sensibilité optimale. La source APPI a été finalement choisie après une étude sur les performances de la méthode. Cette source présente une bonne répétabilité, linéarité et des limites de détection de l’ordre de celles retrouvées dans la littérature par HPLC-MS. Nous avons ensuite réalisé la quantification des ces composés dans 2 types de matrices alimentaire et biologique : l’huile de soja et le plasma de rat. Une troisième partie a été débutée sur le profilage de lipides à polarités variées par SFC-MS. Cette technique se révèle idéale de par la faible polarité de ces composés et leur absence d’absorbance dans le domaine UV. En effet, l’intégrité des lipides peut être altérée suite aux dommages causés par les radicaux libres, qui sont potentiellement impliqués dans de nombreuses maladies neurodégénératives. Il parait primordial de développer des outils analytiques présentant une haute sensibilité et résolution et la possibilité d’accéder aux informations structurales. La source d’ionisation ESI nous a permis de détecter 12 lipides sur les 20 sous-classes analysées en mode positif et 8 lipides en mode négatif. Une application a été réalisée sur un échantillon de plasma humain. Il serait intéressant à l’avenir d’effectuer cette étude en utilisant la source APPI, source propice à l’analyse structurale de lipides et présentant une bonne sensibilité et répétabilité. Ce couplage SFC-MS, présentant une bonne sensibilité et répétabilité, sera par la suite étendu à l’analyse de lipides dans diverses matrices biologiques et pourra à l’avenir être appliqué à l’étude de nouveaux biomarqueurs et au screening rapide d’un grand nombre d’échantillons / The aim of this PhD project was to couple supercritical fluid chromatography (SFC) with a high resolution mass spectrometer for apolar natural compounds analysis. Because mobile phase is principally constituted of CO2, SFC is called “green technic” contrary to normal phase liquid chromatography (NPLC), which uses lot of organic solvents toxic for environment. The CO2 presents a low viscosity, in this way high diffusivity and flow rate, and lower analysis times are obtained. Our work was focused on apolar molecules: the lipids. The aim was to quantify molecules in alimentary and biological matrices and to a lipidomic approach to study Parkinson disease. The first part was to develop the system SFC with a UV detection on a system on loan by Agilent Technologies. This first study was carried out on 6 vitamin A compounds. An optimization of chromatographic parameters has been realized in order to obtain a good separation of the compounds. Then, linearity, repeatability, detection and quantification limits have been determined in order to have a reliable and robust method. A second part concerned the coupling of SFC and a quadrupole time-of-flight mass spectrometer (Q-TOF), in order to improve specificity and sensitivity of analysis. Different ionization sources have been tested: ESI, APCI and APPI. Each ion source presents different ionization mode, which permits to analyze a wide range of polarities of compounds. We have chosen 8 vitamin E derivatives, which are apolar compounds for which SFC seems to be well suited. Separation compounds have been optimized in order to have a good chromatographic resolution and a short analysis time. This compounds ionization is realized with the 3 sources, varying ionization parameters and make-up solvent, to have an optimal sensitivity. The APPI source has been chosen after a performance evaluation method. This source presents a good repeatability, linearity and detection limit in the same order of magnitude than those found in the literature by HPLC-MS. Then we have quantified these compounds in alimentary and biological matrices: a soya oil and plasma rat. A third study has been started on lipid profiling with various polarities by SFC-MS. This technic is well suited because of the low polarity of this molecules and their lack of absorbance in the UV range. The integrity of lipids can be altered with damages caused by free radicals, and are potentially involved in neurodegenerative diseases. It is essential to develop analytical systems with a high sensitivity and resolution and the possibility to access to structural information. The ESI source permits to detect 12 lipids on the 20 sub-classes analyzed in positive ion mode and 8 lipids in negative mode. An application has been realized on human plasma. In the future, it will be interesting to analyze these lipids with the APPI source, which is good choice for structural analysis of lipids, with good sensitivity and repeatability. Studies with this SFC-MS system, presenting good sensitivity and repeatability, will be extended to lipid analysis in biological matrices and could be applied to new biomarkers study and for fast screening of a large number of samples
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