Le chloroacétaldéhyde (CAA), un des principaux produits du métabolisme hépatique de l'ifosfamide (IFO), est considéré comme responsable de la néphrotoxicité de ce médicament. Les mécanismes exacts de cette néphrotoxicité ne sont pas complètement élucidés. Dans la première partie de cette étude, nous avons essayé de préciser les mécanismes physiopathologiques de la toxicité du CAA sur un modèle de tranches de cortex rénal de rat, puis, dans la deuxième partie, nous avons recherché un effet anticancéreux éventuel du CAA sur des cellules de cancer du sein humain (MCF-7). La néphrotoxicité du CAA, utilisé à des concentrations proches de celles mesurées chez les patients traités par l'IFO, soit 0 - 75 µM, s'est manifestée par une chute d'ATP et du glutathion ainsi que par une inhibition du métabolisme du lactate. Certaines enzymes de la néoglucogenèse, notamment la glyceraldéhyde 3-phosphate déshydrogénase, ont été inhibées par le CAA. Le complexe I de la chaîne respiratoire mitochondriale ainsi que l'oxydation du lactate ont été également inhibées par le toxique. D'autre part, le CAA (10 et 25 µM) a inhibé la prolifération des cellules MCF-7 sans que cette inhibition soit accompagnée d'une chute d'ATP cellulaire. Le transport cellulaire et le métabolisme du glucose ainsi que certaines enzymes de la glycolyse ont été également inhibés par le CAA. Parmi celles-ci, l'hexokinase semble être l'enzyme qui catalyse l'étape limitante de la voie de la glycolyse. En conclusion, le CAA est bien impliqué dans les mécanismes de la néphrotoxicité de l'IFO, mais de plus, il pourrait, via l'inhibition de la glycolyse, contribuer à l'effet thérapeutique de l'IFO.

Sex steroids are inevitable in women. However, long-term exposure to sex steroids increases the risk of breast cancer. A complete understanding of sex steroid control of the breast and how it relates to breast cancer risk is still lacking. Angiogenesis and proteolytic enzyme activity are crucial for the process by which tumors evolve into a vascularized, invasive phenotype. Matrix metalloproteinases are potent matrixdegrading enzymes that affect several steps in tumor progression including angiogenesis. In the female reproductive organs, sex steroids regulate angiogenesis and MMP activity, yet little is known how sex steroids affect these crucial events in normal and malignant breast tissue. This thesis elucidates a link between sex steroids, MMP activity, and angiogenesis. It is shown that estradiol down-regulates while tamoxifen up-regulates the protein expression and activity of MMP-2 and MMP-9 in human breast cancer cells in vitro and in human breast cancer xenografts in vivo. The results further suggest that a biological consequence of this regulation may be modulation of tumor angiogenesis. The net effect of adding tamoxifen to estradiol treatment was an increase in extracellular levels of the endogenous angiogenesis inhibitor endostatin and decreased levels of the tumor promoter TGF-β1 compared to estradiol treatment only. This was accompanied by reduced vasculature and decreased tumor growth. Similarly, a regulatory effect of estradiol and tamoxifen on endostatin generation was observed in normal human breast tissue by whole-tissue culture and microdialysis in human breast tissue in situ. In conclusion, the results presented in this thesis suggest previously unknown mechanisms of action of estradiol and tamoxifen in breast cancer and in normal human breast tissue, and novel means by which estradiol may tip the scale to favor angiogenesis. This knowledge may be important for the understanding of sex steroid dependent breast carcinogenesis and in the future development of tissue-specific preventive as well as therapeutic strategies against breast cancer.

Chemotherapy is one of the common treatments in cancer therapy. The effectiveness of chemotherapy is limited by several factors one of which is the emergence of multidrug resistance (MDR). MDR is caused by the activity of diverse ATP binding cassette (ABC) transporters that pump drugs out of the cells. There are several drugs which have been used in treatment of cancer. One of them is doxorubicin that intercalates and inhibits DNA replication. However, doxorubicin has been found to cause development of MDR in tumors. It has been reported that there is a correlation between multidrug resistance and invasiveness of cancer cells. Vimentin is a type III intermediate filament protein that is expressed frequently in epithelial carcinomas correlating with invasiveness and also poor prognosis of cancer. There are several studies that have shown the connection between expression level of vimentin and invasiveness. In this study, MCF-7 cell line (MCF-7/S), which is a model cell line for human mammary carcinoma, and doxorubicin resistant MCF-7 cell line (MCF-7/Dox) were used. The resistant cell line was previously obtained by stepwise selection in our laboratory. The main purpose of this study was to investigate changes of metastatic behaviour in MCF-7/Dox cell line, after transient silencing of vimentin gene by siRNA. In conclusion, down-regulation of vimentin gene expression in MCF-7/Dox cell lines was expected to change the characteristics in migration and invasiveness shown by migration and invasion assays.

Resistance to broad spectrum of chemotherapeutic agents in cancer cell lines and tumors has been called multiple drug resistance (MDR). In this study, the molecular mechanisms of resistance to two anticancer agents (paclitaxel and vincristine) in mammary carcinoma cell line MCF-7 were investigated. MCF-7 cells were selected in the presence of paclitaxel and vincristine by stepwise dose increments. The cell viability and growth profiles of resistant sublines were examined. As the resistance indices increased, the growth rates of sublines were found to decrease. Gene and protein expression levels of the basic drug resistance proteins P-gp and MRP1 were studied in sensitive and drug resistant MCF-7 cells. It was shown that P-gp overexpression is significantly contributing to the developed drug resistance phenotype. Mutation analysis of beta tubulin gene which encodes the target of paclitaxel and vincristine was performed. Single histidine to proline mutation was identified near GTP binding site of beta tubulin in vincristine resistant subline which was not reported before. Apoptosis related BCL-2 and BAX were examined at both gene and protein expression levels and they were not found to be significantly related to the developed resistance in the sublines. The reversal of drug resistance by various inhibitory agents of P-gp and MRP1 was investigated by using flow cytometry. Synthetic silicon compounds were found to be the most effective MDR reversal agents. The effects of various combinations of anticancer drugs and reversal agents on cell proliferation were examined by checkerboard microplate method. ALIS409-paclitaxel and paclitaxel-doxorubicin pairs seem to have highest antiproliferative effects on resistant sublines. The microarray expression profiling of sensitive and resistant MCF-7 cells was performed for a much detailed and comprehensive analysis of drug resistance. The results indicated that the upregulation of MDR1 gene is the dominating mechanism of paclitaxel and vincristine drug resistance. Additionally up regulation of the genes encoding the detoxifying enzymes (i.e. GSTP1) was observed. Significant down regulation of apoptotic genes (i.e. PDCD2/4/6/8) and alterations in expression levels of genes related to invasion and metastasis (MMPs, ADAMs, COL4A2, LAMA etc.) were detected. Upregulation of some oncogenes (i.e. ETS, RAS) and cell cycle regulatory genes (CDKN2A, CCNA2 etc.) was seen which may be in close relation to MDR in breast cancer. Further studies will demonstrate the relationship between the components contributing to drug resistance phenotype in breast cancer cells.

Orientador: Prof. Dr. Anderson Orzari Ribeiro / Tese (doutorado) - Universidade Federal do ABC. Programa de Pós-Graduação em Ciência e Tecnologia/Química, 2017. / No presente trabalho apresentamos a sintese e caracterizacao do fotossensibilizador hipericina e alguns de seus sais hipericinato, bem como o estudo de sua atividade fotodinamica in vitro em celulas de adenocarcinoma mamario humano. A hipericina sintetizada foi caracterizada por espectroscopia 1H RMN, espectrometria de massas e espectroscopia no infravermelho. As propriedades fotofisicas e fotoquimicas da hipericina e dos hipericinatos foram determinadas por analises dos espectros de absorcao na regiao do UV-Vis, espectros de excitacao e emissao, coeficiente de absortividade molar (¿Ã) e capacidade de geracao de especies reativas de oxigenio atraves da degradacao do DPBF (1,3-difenilbenzofurano). Para os estudos in vitro utilizou-se a linhagem de adenocarcinoma mamario humano (MCF-7) avaliando a toxicidade e fototoxicidade da hipericina e hipericinatos, localizacao celular, capacidade mutagenica e genotoxica, capacidade clonogenica, tempo de captacao celular e identificacao de via de morte celular. Os resultados apresentam indicativos de que os hipericinatos possuem eficiencia relativa superior ao da hipericina na producao de oxigenio singlete, bem como uma menor taxa de agregacao em meio biologico. Ainda, nos ensaios in vitro, foi verificado que a atividade fotodinamica foi maior para os hipericinatos em comparacao com a hipericina, demonstrando que as modificacoes moleculares no composto promovem alteracoes na sua interacao com a linhagem celular estudada. / In this study we present the synthesis and characterization of photosensitizers like hypericin and hypericinates and its in vitro photodynamic ativity in human mammary adenocarcinoma cells. The synthesized hypericin was characterized by 1H NMR spectroscopy, mass spectrometry and infrared spectroscopy. The hypericinates were characterized by analysis of absorption spectra in the UV-vis region, excitation and emission spectra, molar absorptivity (å) and reactive oxygen species generation capacity through the degradation of DPBF (1,3-diphenylbenzofuran). For in vitro studies, human mammary adenocarcinoma (MCF-7) lineage was used to evaluate the toxicity and phototoxicity of hypericin and hypericinates, as well as their cell colocalization, mutagenic and genotoxic capacity, clonogenic capacity, time of cellular uptake and path of cell death identification. The results indicated that hypericinates have higher relative efficiency in the production of singlet oxygen than hypericin and lower rate of aggregation in biological medium. Furthermore, in in vitro assays, it was verified that the effectiveness of the photodynamic activity was higher for the hypericinates than hypericin, demonstrating that the molecular modifications in the hypericin macrocycle promotes changes in their interaction with cell line studied.

Philosophiae Doctor - PhD / Globally, breast cancer is the most common cancer affecting women and it is predicted that in 2030 about 12 million deaths will occur with approximately 21.7 million new cases [2]. Genetic risk factors as well as race and ethnicity, account for about 5-10% of all breast cancer occurrences. Triple negative breast cancer (TNBC), tumors that tested negative for oestrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2), contribute to 10-20% of all breast carcinomas [3,4] and is known to be a more aggressive type of cancer with varying degree of response to chemotherapeutic and radiation therapy [5,6] / 2022-02-24

The goal this semestral work is: Simple web server implementation into microcontroller ColdFire MCF 52233. We'll meet with microcontroller family ColdFire MFC 5223X, protocol HTTP 1.1 and Free ColdFire TCP/IP by Interniche. Like last part is suggestion of implementation web server into microcontroller.

[EN] Space-division multiplexing fibers emerged as a promising solution to overcome the imminent capacity crunch of conventional singlemode fiber networks. Despite these fibers were initially conceived as distribution media for long-haul high-capacity digital communications, they can be applied to a wide variety of scenarios including centralized radio access networks for wireless communications, data-center interconnects, Microwave Photonics signal processing and fiber sensing. Particular interest is raised by emerging communications paradigms, such as 5G and The Internet of Things, which require a full integration between the optical fiber and the wireless networks segments. Microwave Photonics, discipline that focuses on the generation, processing, control and distribution of radiofrequency signals by photonics means, is called to play a decisive role. One of the major challenges that Microwave Photonics has to overcome to satisfy next-generation communication demands relates to the reduction of size, weight and power consumption while assuring broadband seamless reconfigurability and stability. There is one revolutionary approach that has however been left untapped in finding innovative ways to address that challenge: exploiting space, the last available degree of freedom for optical multiplexing. In this Thesis, we propose to exploit the inherent parallelism of multicore and few-mode fibers to implement sampled discrete true time delay lines, providing, in a single optical fiber, a compact and efficient approach for both Microwave Photonics signal distribution and processing. For the multicore fiber approach, we study the influence of the refractive index profile of each heterogeneous core on the propagation characteristics as to feature specific group delay and chromatic dispersion values. We designed and fabricated two different heterogeneous trench-assisted 7-core fibers that behave as sampled true time delay lines. While one of them was fabricated by using 7 different preforms to feature a plenary performance, the other one employed a single preform with the aim of minimizing fabrication costs. In the case of few-mode fibers, we propose the implementation of a tunable true time delay line by means of a custom-designed fiber with a set of inscribed long period gratings that act as mode converters to properly tailor the sample group delays. We designed and fabricated a true time delay line on a 4-mode fiber by inscribing 3 long period gratings at specific positions along the fiber link. As a proof-of-concept validation, we experimentally demonstrated different Microwave Photonics signal processing functionalities implemented over both multicore and few-mode fiber approaches. This work opens the way towards the development of distributed signal processing for microwave and millimeter wave signals in a single optical fiber. These true time delay lines can be applied to a wide range of Information and Communication Technology paradigms besides fiber-wireless communications such as broadband satellite communications, distributed sensing, medical imaging, optical coherence tomography and quantum communications. / [ES] La multiplexación por división espacial en fibras ópticas surgió como una solución prometedora al inminente colapso en la capacidad de las redes de fibra monomodo convencionales. Aunque estas fibras fueron concebidas inicialmente como medio de distribución en comunicaciones digitales de larga distancia y alta capacidad, pueden emplearse en una amplia variedad de escenarios, incluyendo redes de acceso radio centralizadas para comunicaciones inalámbricas, interconexiones en centros de datos, así como procesado de señal en Fotónica de Microondas y sensado en fibra. Los paradigmas de comunicaciones emergentes despiertan un interés particular, como 5G y el Internet de las Cosas, que requieren una integración total entre el segmento de red de fibra óptica y el inalámbrico. La Fotónica de Microondas, disciplina que se focaliza en la generación, procesado, control y distribución de señales de radiofrecuencia por medio de la fotónica, está destinada a jugar un papel decisivo. Uno de los mayores desafíos que la Fotónica de Microondas debe superar para satisfacer los requisitos de las nuevas generaciones de comunicaciones se basa en la reducción de tamaño, peso y consumo de potencia, mientras se garantiza reconfiguración y estabilidad de banda ancha. Encontramos aquí un enfoque revolucionario capaz de abordar este desafío de una manera innovadora que, sin embargo, no ha sido aprovechado en este contexto: la explotación del espacio, el último grado de libertad para multiplexación óptica. En esta Tesis, proponemos explotar el paralelismo inherente de las fibras ópticas multinúcleo y de pocos modos para implementar líneas de retardo en tiempo real muestreadas que proporcionan, en una sola fibra óptica, una solución compacta y eficiente tanto para distribución como para procesado de señales de Fotónica de Microondas. En el caso de fibras multinúcleo, estudiamos la influencia del perfil de índice de refracción de cada núcleo heterogéneo en las características de propagación para que exhiba unos valores concretos de retardo de grupo y dispersión cromática. Diseñamos y fabricamos dos fibras distintas de 7 núcleos con zanjas que se comportan como líneas de retardo en tiempo real muestreadas. Mientras que una de ellas se fabricó utilizando 7 preformas diferentes para garantizar un funcionamiento completo, la segunda se fabricó utilizando una única preforma con el objetivo de minimizar costes de fabricación. En el caso de fibras de pocos modos, proponemos la implementación de líneas de retardo en tiempo real sintonizables mediante el uso de una fibra específicamente diseñada y la inscripción de un conjunto de redes de difracción de periodo largo que actúan como conversores de modos para ajustar adecuadamente el retardo de grupo de las muestras. Diseñamos y fabricamos una línea de retardo en tiempo real en una fibra de 4 modos mediante la inscripción de 3 redes de difracción de periodo largo en posiciones concretas a lo largo de enlace de fibra. Como validación de prueba de concepto, demostramos experimentalmente diferentes funcionalidades de procesado de señal de Fotónica de Microondas implementadas en fibras multinúcleo y de pocos modos. Este trabajo abre el camino hacia el desarrollo del procesado de señal distribuido para señales de microondas y ondas milimétricas en una única fibra óptica. Además, las líneas de retardo en tiempo real desarrolladas pueden aplicarse a una amplia variedad de paradigmas de Tecnologías de la Información y Comunicaciones más allá de las comunicaciones radio sobre fibra, como es el caso de las comunicaciones de banda ancha por satélite, el sensado distribuido, la imagen médica, la tomografía óptica coherente y las comunicaciones cuánticas. / [CA] La multiplexació per divisió espacial en fibres òptiques va sorgir com una solució prometedora a l'imminent col·lapse en la capacitat de les xarxes de fibra monomode convencionals. Encara que estes fibres foren concebudes inicialment com a mitjà de distribució en comunicacions digitals de llarga distància i alta capacitat, poden emprar-se en una àmplia varietat d'escenaris, incloent xarxes d'accés radio centralitzades per a comunicacions sense fils, interconnexions en centres de dades, així com processat de senyal en Fotònica de Microones i sensat en fibra. Els paradigmes de comunicacions emergents desperten un interès particular, com el 5G i la Internet de les Coses, que requereixen una integració total entre els segments de xarxa de fibra òptica i el de sense fils. La Fotònica de Microones, disciplina que es focalitza en la generació, processat, control i distribució de senyals de radiofreqüència per mitjà de la fotònica, està destinada a jugar un paper decisiu. Un dels majors desafiaments que la Fotònica de Microones ha de superar per satisfer els requisits de les noves generacions de comunicacions es basa en la reducció de grandària, pes i consum de potència, mentre es garanteix reconfiguració i estabilitat de banda ampla Trobem ací un enfocament revolucionari capaç d'abordar aquest desafiament d'una manera innovadora que, no obstant això, no ha sigut aprofitat encara en este context: la explotació de l'espai, l'últim grau de llibertat per a multiplexat òptic. En aquesta Tesi, proposem explotar el paral·lelisme inherent de les fibres òptiques multinucli i de pocs modes per a implementar línies de retard en temps real de mostres discretes que proporcionen, en una sola fibra òptica, una solució compacta i eficient tant per a distribució com per a processat de senyals de Fotònica de Microones. En el cas de fibres multinucli, estudiem la influència del perfil d'índex de refracció de cada nucli heterogeni en les característiques de propagació perquè exhibisca uns valors concrets de retard de grup i dispersió cromàtica. Dissenyem i fabriquem dues fibres distintes de 7 nuclis amb rases que es comporten com a línies de retard en temps real mostrejades. Mentre que una d'elles es va fabricar utilitzant 7 preformes diferents per a garantir un funcionament complet, la segona va fabricar-se utilitzant una única preforma amb l'objectiu de minimitzar costos de fabricació. En el cas de fibres de pocs modes, proposem la implementació de línies de retard en temps real sintonitzables mitjançant l'ús d'una fibra específicament dissenyada i la inscripció d'un conjunt de xarxes de difracció de període llarg que actuen com a convertidors de modes per tal d'ajustar adequadament el retard de grup de les mostres. Dissenyem i fabriquem una línia de retard en temps real en una fibra de 4 modes mitjançant la inscripció de 3 xarxes de difracció de període llarg en posicions concretes al llarg de l'enllaç de fibra. Com a validació de proba de concepte, demostrem experimentalment diferents funcionalitats de processat de senyal de Fotònica de Microones implementades en fibres multinucli i de pocs modes. Aquest treball obri el camí cap al desenvolupament del processat de senyal distribuït per a senyals de microones i ones mil·limètriques en una única fibra òptica. A més, aquestes línies de retard en temps real poden aplicar-se a una àmplia varietat de paradigmes de Tecnologies de la Informació i Comunicacions més enllà de les comunicacions radio sobre fibra, com es el cas de les comunicacions de banda ampla per satèl·lit, el sensat distribuït, la imatge mèdica, la tomografia òptica coherent i les comunicacions quàntiques. / Agradezco al Ministerio de Economía y Competitividad del Gobierno de España por la financiación recibida mediante la ayuda FPI. / García Cortijo, S. (2020). Distributed radiofrequency signal processing based on space-division multiplexing fibers [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/147858 / TESIS

Utilization of potential synergistic interactions among different bioactive agents is a promising approach to inhibit complex diseases such as cancer. Nobiletin (NBT) and tangeretin (TAN) are major polymethoxyflavones (PMFs) found in citrus fruits. Herein, we studied NBT and TAN in combination with atorvastatin (ATST, Lipitor, a cholesterol-lowering drug) in MDAMB231 and MCF-7 human breast cancer cells. Both NBT/ATST and TAN/ATST combinations at low doses produced much stronger inhibitory effect on cancer cell viability in comparison to those produced by NBT, TAN, or ATST alone at much higher doses. Isobologram analysis confirmed that both NBT/ATST and TAN/ATST combinations produced strong synergy in inhibiting the growth of two breast cancer cell lines. Flow cytometry analysis showed that both NBT/ATST and TAN/ATST combinations caused significant cell cycle arrest at G0/G1 phase in MDAMB231 cells (ER+). Consistent with these results, PMFs and ATST combinations decreased expression levels of phospho Rb, cyclin D1, and CDK4. Further experiments showed that the combination treatment induced autophagy and late apoptosis in MDA-MB-231 cells. Meanwhile, co-treatment of PMFs and ATST induce G2/M phase in MCF-7 (ER+) cells.. The combination of PMFs and ATST also caused autophagy in MCF-7 cells, which was evidenced by activation of LC3B and P62. In conclusion, our result demonstrated strong synergy between two major citrus PMFs (NBT and TAN) and ATST in inhibiting human breast cancer cell growth.

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