Made available in DSpace on 2014-06-11T19:23:01Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-02-15Bitstream added on 2014-06-13T18:50:11Z : No. of bitstreams: 1 bannwart_cf_me_botfm.pdf: 462065 bytes, checksum: 2e3988993f9db6f1ef7a8c8058e75e6a (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / A interleucina-15 (IL-15) é uma citocina pró-inflamatória produzida principalmente por monócitos e macrófagos em resposta a agentes infecciosos, desempenhando importante papel modulador na imunidade inata e adaptativa. O objetivo do presente trabalho foi avaliar o efeito da IL-15 sobre a atividade fungicida, metabolismo oxidativo e a produção de citocinas por monócitos humanos, infectados in vitro com cepa virulenta de Paracoccidioides brasiliensis (Pb18). Monócitos de sangue periférico, obtidos de indivíduos saudáveis, foram préincubados na ausência ou presença de IL-15 (12,5, 25 e 50 ng/mL) por 24 h a 37oC e infectados com Pb18 na proporção de 50 monócitos para uma célula fúngica durante 4 h e 18 h. A atividade fungicida de monócitos foi determinada após 4 h pela recuperação de fungos viáveis por plaqueamento das co-culturas em meio BHI-ágar. O metabolismo oxidativo foi avaliado pela liberação de peróxido de hidrogênio (H2O2) e de ânion superóxido (O2 -) nas culturas desafiadas com Pb18 e estimuladas com phorbol myristate acetate (PMA) durante 60 mim. A produção de fator de necrose tumoral-alfa (TNF-a), IL-6, IL-10 e IL-15 foi determinada por ensaio imunoenzimático (ELISA) nos sobrenadantes das coculturas obtidos após 4 e 18 h de incubação. Os resultados mostraram que a préincubação de monócitos com IL-15 induziu aumento significativo na atividade fungicida contra Pb18 de maneira dose-dependente, sendo esse efeito neutralizado pela adição de anticorpo monoclonal anti-IL-15. O tratamento com IL- 15 não interferiu na capacidade de liberação de H2O2 e O2 - por monócitos desafiados com Pb18 sugerindo que a atividade fungicida estimulada por IL-15 ocorre por mecanismos independentes do metabolismo oxidativo. Monócitos infectados com o fungo, na ausência de IL-15, produziram níveis de TNF-a, IL-6 e IL-10... / Interleukin-15 (IL-15) is a pro-inflammatory cytokine especially produced by monocytes and macrophages against infectious agents and that play a pivotal role in teh innatte and adaptive immune response. The aim of this study was to analyze the effects of IL-15 on fungicidal activity, oxidative metabolism and cytokine production by human monocytes challenged in vitro with a virulente strain of Paracoccidioides brasiliensis (Pb18). Peripheral blood monocytes obtained from healthy individuals were pre-incubated for 24h with or without human recombinant IL-15 (12.5,25 and 50 ng/mL), and then challenged with Pb18 in a ratio of 50:1 monocytes:fungi. Fungicidal activity of monocytes against Pb18 was assessed by viable fungi recovery from 4 h co-cultures after plating in BHI-agar. Oxidative metabolism was evaluated by hydrogen peroxide (H2O2) and superoxide anion (O2 -) release in the monocyte cultures challenged by Pb18 and stimulated with phorbol myristate acetate (PMA) for 60 min. Tumor necrosis factor-alpha (TNF-a), IL-6, IL-10 and IL-15 production by monocytes were determined in culture supernatants by enzyme immunoassay (ELISA). The results showed that IL-15 ehanced fungicidal activity against Pb18 in a dose-dependent pattern. This effect was abrogated by additon of anti-IL-15 monoclonal antibody to the co-cultures. No significant effect of IL-15 on H2O2 and O2 - release by monocytes was observed suggesting that the fungicidal activity was independent of oxidative metabolism activation. Monocytes infected with P. brasiliensis in the absence of IL-15, produced significantly higher levels of TNF-a, IL-6 and IL-10 after 18 h of coculture in comparison to experiments of 4h-incubation with the fungus. The pretreatment of monocytes with IL-15 induced significant higher levels of TNF-a, IL-10 and IL-15 production by these cells challenged with the fungus... (Complete abstract click eletronic address below)

Considering the crucial involvement of matrix metalloproteinases’ (MMPs) misregulated activity in the pathogenesis of several degenerative diseases, this class of enzymes has been considered a highly active set of targets for the design of new therapeutic agents. However, the scant success of synthetic MMP inhibitors, largely due to the disappointing results obtained in both clinical and preclinical studies, makes medicinal plants a valuable source of new active compounds able to modulate MMPs activity. In this work, a consistent number of plants, selected on the base of an ethnobotanical research, were tested as inhibitors of collagenase, the founding member of the MMPs family. 1H-NMR-based metabolomic analysis combined with multivariate data treatment (PLS and OPLS) was used to correlate the biological activity to the phytochemical profiles, suggesting tannins as an important class of collagenase inhibitors. Thus, a tannin-removal procedure was developed, which allowed to prove this hypothesis and to identify another class of active metabolites, the glucuronide-conjugated flavonoids (especially quercetin-3-O-β-glucoronide), whose the plant Alchemilla vulgaris was found to be a good source. In another stage of the project, different varieties of tea were investigated as collagenase inhibitors, finding black tea samples particularly potent. Then, an OPLS model was developed with the aim of correlating the biological activity to the UV-Vis spectra of teas, showing that a high activity was related to absorption values in the range 350-440 nm. A subsequent fractionation of the most active tea sample was carried out, and this approach allowed to corroborate the results obtained by the metabolomic analysis. Considering that the absorbance measurement of an extract represents a cheap and simple procedure, the proposed method can be suitable, for instance, to select the best tea variety to be developed as an anti-wrinkles cosmetic or food supplement.

Les maladies inflammatoires chroniques de l’intestin (MICI) telles que la maladie de Crohn et la rectocolite hémorragique sont des maladies chroniques dans lesquelles interviennent des facteurs environnementaux, immunologiques et génétiques. Récemment, il a été montré que la barrière épithéliale intestinale (BEI) était impliquée dans la physiopathologie des MICI, et des approches visant à améliorer la résistance et la réparation de cette BEI représentent de nouvelles pistes thérapeutiques prometteuses. Notre laboratoire a largement contribué ces dernières années à identifier les cellules gliales entériques (CGE), comme un nouveau composant clé du microenvironnement de la BEI, renforçant la protection de la BEI et sa cicatrisation. A l'inverse, chez les patients MICI, les CGE sont altérées à la fois d'un point de vue phénotypique et fonctionnel. Dans ce contexte, outre une meilleure compréhension des mécanismes physiopathologiques, le but de ce projet visait à identifier les CGE comme une nouvelle cible d’intérêt thérapeutique dans les MICI. Grâce à une analyse lipidomique, nous avons mis en évidence une sousproduction de différents médiateurs lipidiques par les CGE de patients MICI. Parmi eux, le 15-HETE et la PGI2 étaient capables de réguler la perméabilité de la BEI, à la fois in vitro et in vivo. De plus, ils semblaient capables de restaurer les fonctions perdues chez les patients MICI. Ainsi, nos travaux suggèrent qu'une sous-production des ces médiateurs lipidiques par les CGE de patients MICI pourraient concourir aux mécanismes physiopathologiques, et représentent une nouvelle piste thérapeutique majeure. / Chronic inflammatory bowel disease (IBD) such as Crohn's disease and ulcerative colitis are chronic diseases involving environmental, immunological and genetic factors. Recently, the intestinal epithelial barrier (IEB) has been shown to be involved in the pathophysiology of IBD, and approaches to improve the resistance and repair of this IEB represent promising new therapeutic pathways. Our laboratory has made a significant contribution in recent years to identifying enteric glial cells (EGC) as a key new component of the IEB microenvironment, enhancing IEB protection and healing. Conversely, in IBD patients, EGC are altered both phenotypically and functionally. In this context, in addition to a better understanding of physiopathological mechanisms, the aim of this project was to identify EGC as a new therapeutic target in IBD. Using a lipidomic analysis, we have demonstrated the underproduction of various lipid mediators by the EGC from IBD patients. Among them, 15-HETE and PGI2 were able to regulate the permeability of the IEB, both in vitro and in vivo. In addition, they appeared to be able to restore functions lost in IBD patients. Thus, our work suggests that underproduction of these lipid mediators by EGC from IBD patients could contribute to pathophysiological mechanisms and represent a new major therapeutic target.

O objectivo da presente dissertação passa por analisar a influência da presença na burocracia régia no movimento de titulação que se faz sentir ao longo do século XV. Para tal, foi estudado o caso do Dr. João Fernandes da Silveira, prestigiado oficial régio e elevado a barão de Alvito em 1475, que apresenta ainda a particularidade de ter sido, ao que tudo indica, o primeiro titular de origem popular. Numa primeira instância, será exposta a evolução da burocracia régia no decurso de Quatrocentos, acompanhando o trajecto ascendente de uma parte considerável dos oficiais pertencentes ao clero, nobreza e povo. De seguida, serão analisados três dos factores que irão marcar a evolução da nobreza quatrocentista: a curialização da nobreza; o desenvolvimento de uma nobreza de serviço; e um movimento alargado de titulação, visível sobretudo a partir de Alfarrobeira. A ascensão do Dr. João Fernandes da Silveira será analisada com base na confluência destes factores, onde se poderão encontrar as causas da sua titulação.

D. Luís foi capelão em 1433, quando D. Duarte subiu ao trono, e era arcebispo de Braga quando morreu em 1480. Ao longo destes 43 anos foi embaixador régio, legado papal na Alemanha, bispo em três dioceses nacionais e responsável por um dos sínodos diocesanos mais importantes para o período medieval. No contexto nacional, foi testemunha directa dos momentos políticos que conduzirama Alfarrobeira. Já no âmbito europeu, foi um privilegiado espectador do despontar da arte e cultura renascentista na Itália. Assistiu também ao definhar do Sacro Império Romano-Germânico e à queda de Constantinopla em 1452. Para a cronologia o seu século corresponde ao fim da Idade Média. Logo D. Luís surge-nos como um tema cativantepara todos os que se interessam pelo estudo da Baixa Idade Média. Mais, para todos os que se interessam pela história eclesiástica desta época dado que viveu, de forma quase exclusiva, para o desempenho da missão pastoral inerente à sua condição de homem da Igreja. É impossível separá-lo da instituição eclesiástica, pois a sua identidade foi radicalmente condicionada pelas suas férreas orientações religiosas. E é nesta perspectiva que encontramos o fio unificador da sua vida.

L'incroyable augmentation d'objets connectés dans le monde de l'Internet des Objets impliquera plusieurs problèmes. L'efficacité énergétique est un des principaux. Le présent travail étudie l'efficacité énergétique et, plus précisément, la modélisation de l'énergie consommée par le nœud.Nous avons créé une plateforme matérielle et logicielle appelée Synergie. Cette plateforme est composée d'un ensemble d'outils matériel/logiciel :- un dispositif de mesure de la consommation d'énergie;- un algorithme qui crée automatiquement un modèle de la consommation de l'énergie;- un estimateur de la durée de vie du nœud.La plateforme des mesures de l'énergie récupère les valeurs de courant directement du nœud. Ces courants sont mesurés composant par composant du circuit et fonction par fonction du logiciel embarqué. Cette analyse matérielle/logicielle offre information sur le comportement de chaque composant.Un algorithme crée automatiquement un modèle de la consommation énergétique basé sur une chaîne de Markov. Ce modèle est une représentation stochastique du comportement énergétique du nœud en fonctionnement in situ. Le nœud fonctionne dans un réseau réel et dans des conditions réelles de canal.Finalement, une estimation de la durée de vie du nœud est réalisée en utilisant des modèles de batterie. L'estimation est possible grâce au caractère stochastique du modèle de la consommation. La possibilité de simplement changer les paramètres de consommation pour améliorer la durée de vie est présentée.Ce travail représente la première étape d'un projet global qui a pour but obtenir des réseaux de capteurs sans fil autonomes en énergie. / The significant increase of connected objects in Internet of Things will entail different problems. Among them, the energy efficiency. The present work deals with the energy efficiency and more precisely with the study of the modeling of the energy consumption in the node.We have designed a platform to instrument a node of wireless sensor network in its real environment. The hardware and software platform is made of:- a hardware energy measurement platform;- a software allowing the automatic generation of an energy consumption model;- a node lifetime estimation algorithm.The energy measurement platform recovers the current values directly from the node under evaluation, component per component in the electronic circuit and function per function of the embedded software. This hardware/software analysis of the energy consumption offers important information about the behavior of each electronic component in the node.An algorithm carries out a statistical analysis of the energy measurements. This algorithm creates automatically an energy consumption model based on a Markov chain. Thus, this platform allows to create a stochastic model of the energy behavior of a real node, in a real network and in real channel conditions. The model is made in contrast to the deterministic energy models found in the literature, whose energy behavior is extracted from the datasheets of the components. Finally, we estimate the node lifetime based on battery models. We also show on examples the simplicity to change some parameters of the model in order to improve the energy efficiency.

TiO2 nanoparticles were successfully synthesized by a wet impregnation method using SBA-15 or AP-SBA-15 as the template for confining the growth of TiO2 nanocrystals followed by acclimation at 550 ¢J in muffle furnace for 6 hrs. These uniform nano-sized TiO2 particles are difficult to prepare using the conventional sol-gel process since the decomposition of the Ti precursor proceeds rapidly to form large aggregates, resulting in a wide particle size distribution. The as-synthesized samples were characterized with powder X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectra (FTIR), and nitrogen adsorption isotherm. Results from TEM reveal that the TiO2 nanoparticles are highly dispersed in the channels of SBA-15; subsequent removal of the SBA-15 channels with HF gives the pure TiO2 nanoparticles having a diameter of ~ 9 nm. On the other hand, the bulk TiO2 outside the SBA-15 channels mainly forms aggregated large TiO2 particles. Prior treatment of SBA-15 surface with the coupling agent APTS (AP-SBA-15) enhances the easy chemosorption of a great number of titanium. Subsequent hydrolysis of the anchored Ti complexes and calcinations of the amorphous TiO2, anatase TiO2 nanocrystals yields uniform TiO2 nanoparticles having diameter of ~ 5 nm, as compared to the unconfined bulk TiO2 of 15~50 nm in diameter.

The experiments described in the thesis for my PhD were addressed to the study of the anticancer activity of a conjugate of doxorubicin (DOXO) with lactosaminated human albumin (L-HSA) on hepatocellular carcinomas (HCCs) induced in rats by diethylnitrosamine. L-HSA is a neoglycoprotein exposing galactosyl residues. The conjugate was prepared to improve the chemo therapeutic index of DOXO in the treatment of the well differentiated (WD) HCCs whose cells mantain the receptor for galactosyl terminating glycoproteins and consequently can actively internalize L-HSA. In my first experiments I found that L-HSA coupled DOXO produced concentrations of DOXO higher than those raised by an equal dose of free drug, not only in WD HCCs, but also in the poorly differentiated forms (PD) of these tumors which do no express the receptor for galactosyl terminating glycoproteins. Subsequently I provided evidence that penetration of L-HSA-DOXO in PD HCCs was due to a non-specific adsorption mediated by the DOXO residues of the conjugate which interact with the cell surface mainly because at physiological pH they are positively charged and bind to anionic phospholipids of the cell membrane. In subsequent experiments, by ultrasound technique, I studied the action of free and L-HSA coupled DOXO on the growth of rat HCCs. I found that L-HSA coupled DOXO hindered the development of new neoplastic nodules and inhibited the growth of the established tumors. In contrast, the free drug neither inhibited the development of HCCs nor prevented the growth of the established tumors. Moreover, the free drug produced a severe loss of weight of rats, a sign of severe toxicity, which was not caused by the conjugate. In conclusion assuming that the results obtained in rats can be applied to patients, the results of my thesis suggest that the conjugate by increasing the efficacy and tolerability of DOXO could improve the value of this drug in the treatment of human HCCs.

No description available.

Background. Neuroblastoma is the most deadly solid tumor of childhood. In the 25% of cases it is associated with MYCN amplification (MA), resulting in the disregulation of several genes involved in cancer progression, chemotherapy resistance and poor prognosis causing the disregulation of several genes involved in cancer progression and chemotherapy resistance and resulting in a poor prognosis. Moreover, in this contest, therapy-related p53 mutations are frequently found in relapsed cases conferring an even stronger aggressiveness. For this reason, the actual therapy requires new antitumor molecules. Therefore, rapid, accurate, and reproducible preclinical models are needed to evaluate the evolution of the different subtypes and the efficacy of new pharmacological strategies. Procedures. We report the real-time tumorigenesis of MA Neuroblastoma mouse models: transgenic TH-MYCN mice and orthotopic xenograft models with either p53wt or p53mut, by non-invasive micro PET and bioluminescent imaging, respectively. Characterization of MYCN amplification and expression was performed on every collected sample. We tested the efficacy of a new MYCN inhibitor in vitro and in vivo. Results. MicroPET in TH-MYCN mice permitted the identification of Neuroblastoma at an early stage and offered a sensitive method to follow metabolic progression of tumors. The MA orthotopic model harboring multitherapy-related p53 mutations showed a shorter latency and progression and a stronger aggressiveness respect to the p53wt model. The presence of MA and overexpression was confirmed in each model and we saw a better survival in the TH-MYCN homozigous mice treated with the inhibitor. Conclusions. The mouse models obtained show characteristics of non-invasiveness, rapidity and sensitivity that make them suitable for the in vivo preclinical study of MA-NB. In particular, our firstly reported p53mut BLI xenograft orthotopic mouse model offers the possibility to evaluate the role of multitherapy-related p53 mutations and to validate new p53 independent therapies for this highly aggressive Neuroblastoma subtype. Moreover, we have shown potential clinical suitability of an antigene strategy through its cellular and molecular activity, ability to specifically inhibit transcription and in vivo efficacy with no evidence of toxicity.