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Testování nových nanomateriálů pro teranostické aplikace u modelu myšiDonovalová, Alexandra January 2017 (has links)
Theranostics is connecting two medical branches, diagnostic and therapy. It enables transport of drugs and diagnostic imaging in one step. Nanoparticles, nanotubes, lipozomes or apoferritin can be used as platform for targeted transport. Apoferritin (APO) is a protein from ferritin family, which is characterized by an empty cavity. Is possible encapsulate some cargo (e.g., drug) into this cavity. Encapsulation is done by pH change. There is a possibility to modify APO surface. It causes targeted transport to for example cancer cells. In this study, process of preparation of targeted nanotransporter based on APO is described; next, its characterization by in vitro experiments is shown. The prepared targeted nanotransporter delivered drug to cancer cells and in the same time was decreased toxicity on surrounding tissue and organs.
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Nanoparticules d'oxydes de fer PEGylées pour la délivrance de la doxorubicine : développement et évaluation de leur potentiel théragnostique. / PEGylated iron oxide nanoparticles for doxorubicin delivery : development and evaluation of a potential theragnostic systemGautier, Juliette 19 June 2013 (has links)
Des nanoparticules d’oxydes de fer superparamagnétiques (SPIONs) PEGylées ont servi de plateforme pour la formulation de nanovecteurs théragnostiques pour la délivrance d’un agent anticancéreux, la doxorubicine (DOX). Le chargement de la DOX sur les nanovecteurs à l’aide d’un complexe avec l’ion fer (II) a été optimisé. Ce complexe se dissocie en milieu acide, typique des compartiments intracellulaires. La spectroscopie Raman exaltée de surface (SERS) a confirmé que les nanovecteurs libèrent la DOX sous forme non complexée. La cytotoxicité in vitro induite par la libération de la DOX a été évaluée sur différentes lignées cellulaires de cancer du sein, et comparée à celle de la DOX en solution. Les voies d’internalisation des nanovecteurs ont été explorées en microscopie électronique en transmission (MET), et le devenir intracellulaire de la DOX a été suivi en imagerie confocale multispectrale (ICMS). Enfin, un protocole thérapeutique in vivo chez la souris tumorisée a permis d’évaluer la capacité de la nanoformulation à limiter la croissance tumorale, la possibilité d’un ciblage magnétique, et la réduction des effets secondaires induits par la DOX. / PEGylated superparamagnetic iron oxide nanoparticles (SPIONs) were used as a platform to build theranostic nanovectors for the delivery of an anticancer drug, doxorubicin (DOX). The DOX loading on nanocarriers via a DOX-iron (II) complex was optimized. The complex dissociates at low pH, typical of intracellular compartments. Surface enhanced Raman scattering (SERS) confirmed that the nanovectors released DOX under free form. In vitro cytotoxicity due to DOX loaded on nanocarriers was performed on different breast cancer cells, and compared to that of DOX in solution. Internalization pathways of nanovectors were explored with transmission electron microscopy (TEM), and intracellular fate of DOX was monitored by confocal spectral imaging (CSI). To finish, a therapeutical protocol was performed on tumorized mice, in order to evaluate the efficacy of the nanoformulation on tumor reduction, the possibility of magnetic targeting, and the decrease of side effects induced by DOX.
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Avaliação da influência da matriz extracelular no desenvolvimento de metástases pulmonares em modelos de tumor de mama após o tratamento com doxorrubicina associada à nanoemulsõesCardador, Camila Magalhães 20 August 2018 (has links)
Dissertação (mestrado)—Fundação Universidade de Brasília, Programa de Pós-Graduação em Biologia Animal, 2018. / No câncer de mama as metástases estão intimamente relacionadas com modificações na matriz
extracelular, onde a modificação mais proeminente observada em estudos recentes é o aumento da
deposição de colágeno. As terapias atuais são pouco eficazes em impedir o desenvolvimento e
progressão da doença, bem como a reincidência da mesma ao longo dos anos. Com o intuito de
incrementar os efeitos da terapia, a associação entre a nanotecnologia e os fármacos utilizados busca
melhorar aspectos do tratamento como a eficácia e diminuir os efeitos adversos relacionados ao seu
uso. No presente trabalho um modelo de enxerto tumoral de células de carcinoma mamário murino
(4T1®ATCC), a uma concentração de 4x104 células/50μL de meio de cultivo, enxertadas no flanco
esquerdo de camundongos BalbC fêmeas foi utilizado para avaliação da eficácia do quimioterápico
doxorrubicina associado a nanoemulsões e administração simultânea de losartana. Visando
potencializar o efeito da terapia, a administração simultânea de losartana foi utilizada como uma
tentativa de diminuir os níveis de deposição de colágeno na matriz extracelular de tecidos pulmonares
e facilitar a chegada do fármaco aos sítios alvos por meio da ação descompressora dos vasos que
permeiam o microambiente tumoral. O tratamento foi administrado por cinco dias consecutivos após
quatro semanas do enxerto, nas concentrações de 20mg/kg para doxorrubicina em sua forma livre,
20mg/kg+ 40mg/kg para doxorrubicina livre e losartana, 40mg/kg para doxorrubicina associada a
nanoemulsão e 40mg/kg + 40mg/kg para doxorrubicina associada a nanoemulsão e losartana,
respectivamente. O acompanhamento in vivo do estado clínico dos camundongos ao longo de cinco
semanas mostrou que o tratamento com nanoemulsão e losartana não foi tóxico, enquanto a
doxorrubicina promoveu toxicidade que pôde ser observada no comportamento e aspecto físico dos
camundongos. As avaliações ex vivo de materiais biológicos realizadas por meio de histologia,
imunohistoquímica, ELISA e contagem de nódulos corroboram dados encontrados em estudos
científicos, como o menor nível de colágeno nos grupos com administração simultânea de losartana e
menor grau metastático. Concluiu-se que a doxorrubicina associada a nanoemulsões e administração
de losartana não apresentou diferenças significativas em comparação à doxorrubicina em sua forma
livre quando se trata da atividade antitumoral no sítio primário, mas foi capaz de diminuir o grau de
colágeno encontrado nos tecidos, bem como as metástases nos tecidos pulmonares, não apresentando
toxicidade significativa para os camundongos. / In breast cancer metastasis are closely related to changes in the extracellular matrix, where the most
prominent modification observed in recent studies is the increase in collagen deposition. Current
therapies are poorly effective in preventing the development and progression of the disease, as well as
its recurrence over the years. In order to increase the effects of therapy, the association between
nanotechnology and the drugs aims to improve treatment efficacy and to reduce adverse effects related
to its use. In the present work a murine mammary carcinoma cell (4T1®ATCC) tumor graft model, at a
concentration of 4x10 4 cells/50μl culture medium, grafted on the left flank of female BalbC mice was
used to evaluate the efficacy of doxorubicin with nanoemulsions and simultaneous administration of
losartan. In order to potentiate the effect of the therapy, the simultaneous administration of losartan was
used as an attempt to decrease the levels of collagen deposition in the extracellular matrix of lung
tissues and to facilitate the drug delivery at the target sites through the decompressive action of the
vessels that permeate the tumor microenvironment. The treatment was administered for five
consecutive days after four weeks of grafting, at concentrations of 20mg/kg for doxorubicin in its free
form, 20mg/kg + 40mg/kg for free doxorubicin and losartan, 40mg/kg for doxorubicin associated with
nanoemulsion and 40mg/kg + 40mg/kg for doxorubicin associated with nanoemulsion and losartan,
respectively. In vivo monitoring of the clinical status of mice over five weeks showed that treatment with
nanoemulsion and losartan was non-toxic, whereas doxorubicin promoted toxicity that could be
observed in the behavior and physical appearance of the mice. Ex vivo evaluations of biological
materials performed using histology, immunohistochemistry, ELISA and lung nodule counts corroborate
data found in scientific studies, such as the lower level of collagen in the groups with simultaneous
administration of losartan and lower metastatic degree. It was concluded that doxorubicin associated
with nanoemulsions and administration of losartan did not present significant differences compared to
doxorubicin in its free form when it treated the antitumor activity at the primary site, but was able to
decrease the degree of collagen found in the tissues, as well as metastasis in the lung tissues, showing
no significant toxicity to the mice.
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Nanocápsulas com núcleo de óleo de rícino e invólucro de poli(metil vinil co-anidrido maleico) contendo doxorrubicina : desenvolvimento e avaliação de sua atividade citotóxica contra células de câncer de mama humano e murino in vitroCoelho, Janaína Moreira 24 February 2017 (has links)
Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Biológicas, Pós-Graduação em Nanociência e Nanobiotecnologia, 2017. / Submitted by Raquel Almeida (raquel.df13@gmail.com) on 2017-06-13T18:51:55Z
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Previous issue date: 2017-06-27 / Doxorrubicina (DOX) é um fámaco altamente utilizado no tratamento de diversos tipos de câncer, porém apresenta efeitos adversos, tais como cardiotoxicidade irreversível. O óleo de rícino, um triacilglicerídeo natural vem sendo investigado como veículo de fármacos. O objetivo geral deste trabalho consistiu em desenvolver nanocápsulas com núcleo de óleo de rícino e DOX e avaliar sua atividade contra células de câncer de mama humano e murino in vitro. Foram obtidas nanocápsulas com núcleo de óleo de rícino e doxorrubicina com invólucro de poli (metil vinil-éter co-anidrido maléico) modificado com n-octadecilamina. As nanocápsulas apresentaram-se estáveis e monodispersas. Nos ensaios in vitro, foram utilizadas as células de adenocarcinoma mamário murino (4T1), fibroblasto murino (NIH-3T3), adenocarcinoma mamário humano (MCF-7) e célula de epitélio mamário humano (MCF-10A). O tratamento com NCR-DOX (nanocápsulas com invólucro de PVM/MA e núcleo contendo óleo de rícino e DOX) diminuiu a viabilidade e a adesão de células tumorais. NCR-DOX foi mais interiorizada que DOX livre em células tumorais. A distribuição intracelular da NCR-DOX foi identificada no citoplasma e no núcleo. Os tratamentos com DOX e NCR-DOX em 4T1 e MCF-7 alteraram os padrões morfológicos e diminuíram a confluência de células cancerosas, além disso, provocaram despolarização da membrana e causaram necrose e apoptose tardia. NCR-DOX causou menos fragmentação de DNA do que DOX. Concluiuse que nanocápsulas com núcleo de óleo de rícino e doxorrubicina são eficazes contra células tumorais MCF-7 e 4T1. / Doxorubicin (DOX) is an often used drug for the treatment of several types of cancer, but it has adverse side effects such as irreversible cardiotoxicity. Castor oil, a naturally occurring triacylglyceride, has been investigated as a drug vehicle. The overall objective of this work was to develop nanocapsules with castor oil nuclei containing DOX and evaluate its activity against human and murine breast cancer cells in vitro. Nanocapsules were obtained using with castor oil core and doxorubicin with noctadecylamine modified poly (methyl vinyl ether co-anhydride) casing. The nanocapsules were stable and monodisperse. In the in vitro assays, murine mammary adenocarcinoma (4T1), murine fibroblast (NIH-3T3), human mammary adenocarcinoma (MCF-7) and human mammary epithelial cells (MCF-10A) were used. NCR-DOX treatment decreased the viability and adhesion of tumor cells. NCR-DOX was more internalized than free DOX in tumor cells. The intracellular distribution of NCR-DOX was identified in the cytoplasm and nucleus. The DOX and NCR-DOX treatments in 4T1 and MCF-7 altered the morphological patterns and decreased the confluence of cancer cells. In addition, they provoked depolarization of the membrane and caused necrosis and late apoptosis. NCR-DOX caused less DNA fragmentation than DOX. It was concluded that castor oil core doxorubicin nanocapsules is effective against MCF-7 and 4T1 tumor cells.
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Nanocápsulas de selol com invólucro de poli(metil vinil-éter co-anidrido maléico) conjugado à doxorrubicina : desenvolvimento e avaliação de seu potencial anticâncer in vitro e in vivoGanassin, Rayane 29 February 2016 (has links)
Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Biológicas, Programa de Pós-Graduação em Biologia Animal, 2016. / Submitted by Fernanda Percia França (fernandafranca@bce.unb.br) on 2016-03-28T20:26:57Z
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2016_RayaneGanassin.pdf: 5116718 bytes, checksum: 6bf106395a30603681f312e0e0583e9c (MD5) / A doxorrubicina (DOX) tem se mostrado eficaz no tratamento de cânceres sólidos e hematológicos, mas a sua potencial cardiotoxicidade irreversível, limita o sucesso do tratamento, levando a um baixo índice terapêutico. O selol, mistura de selenitotriacilglicerídeos, mostrou atividade citostática em ensaios in vitro e demonstrou habilidade em reduzir a viabilidade de células resistentes à DOX. Os objetivos gerais do presente trabalho foram: 1) desenvolver uma nanocápsula contendo selol e doxorrubicina com diâmetro próximo a 200 nm, 2) avaliar sua atividade anticâncer in vitro e in vivo, e 3) verificar o seu potencial cardiotóxico. A formulação obtida consistiu de nanocápsulas com núcleo de selol e com invólucro de poli(metil vinil-éter co-anidrido maléico) conjugado à doxorrubicina. As nanocápsulas apresentaram-se estáveis e monodispersas. Para os testes in vitro, foram utilizadas as células de adenocarcinoma mamário murino (4T1) e células de fibroblasto murino como célula não tumoral (NIH-3T3). Os tratamentos DOX (doxorrubicina), NCS-DOX (nanocápsulas de selol contendo doxorrubicina) e Pol-DOX (produto da reação entre PVM/MA e doxorrubicina) provocaram significativa redução na viabilidade de células 4T1. Ensaios de interiorização mostraram que NCS-DOX e Pol-DOX são mais interiorizadas do que DOX livre em células 4T1. NCS-DOX manteve o potencial da DOX em expor a fosfatidilserina na face externa da membrana em células 4T1, sendo este evento um dos que indica a ocorrência de apoptose. NCS-DOX apresentou maior capacidade de provocar fragmentação de DNA, além de provocar maior alteração na polarização mitocondrial do que DOX. NCS-DOX também foi capaz de gerar maior produção de EROs em tempos de 3 e 24 horas de exposição do que DOX. NCS-DOX e Pol-DOX alteraram a distribuição intracelular da DOX quando comparados com a exposição à DOX livre, do núcleo para a mitocôndria. Em estudos in vivo a NCS-DOX apresentou mesma habilidade da DOX em reduzir o crescimento do tumor de células 4T1, além de apresentar a mesma biodistribuição em camundongos BALB/c. A NCS-DOX não elevou os níveis de CK-MB quando comparado ao controle, o mesmo efeito não foi observado para DOX livre. Portanto, conclui-se que a NCS-DOX é eficaz contra células cancerosas 4T1 in vitro e in vivo, e menos cardiotóxica que a DOX in vivo. ______________________________________________________________________________________________ ABSTRACT / Doxorubicin (DOX) has shown to be effective in the treatment of solid and haematological cancers, but its potential irreversible cardiotoxicity limits the success of the treatment, lowering its therapeutic index. The selol, selenitotriacylglicerides mixture, has shown cytostatic activity in in vitro tests and ability to reduce the viability of doxorubicin-resistant cells. The general goals of this study were: 1) to develop nanocapsules containing selol and doxorubicin with diameter close to 200 nm, 2) to evaluate its in vitro and in vivo anticancer activity, and 3) to check its cardiotoxicity. The formulation consisted of nanocapsules with a core of selol and a shell of poly (methyl vinyl ether-co-maleic anhydride) conjugated to doxorubicin. The nanocapsules were stable and monodisperse. For in vitro tests, murine mammary adenocarcinoma cells (4T1) and fibroblast murine as non-tumor cell (NIH-3T3) were used. The treatments DOX (doxorubicin), NCS-DOX (nanocapsules of selol containing doxorubicin) and Pol-DOX (product of the reaction between PVM/MA and doxorubicin) caused a significant reduction in the viability of 4T1 cells. Internalization assays showed that NCS-DOX and Pol-DOX are more internalized than free DOX by 4T1 cells. NCS-DOX, similarly to free DOX, expose phosphatidylserine on the outside face membrane in 4T1 cells, this is an event that indicate apoptosis. NCS-DOX showed an increased ability to cause DNA fragmentation and to disturb the mitochondrial membrane polarization in comparison to free DOX. NCS-DOX was also able to induce higher production of ROS, at 3 and 24 hours of exposure. NCS-DOX and Pol-DOX altered intracellular distribution of doxorubicin when compared to free DOX alone, from the nuclei to the mitochondria. In in vivo studies, NCS-DOX and free DOX showed the same ability to reduce 4T1 tumor growth, and presented the same biodistribution in BALB/c mice. The NCS-DOX did not increase CK-MB levels when compared to the control. Free DOX significantly increased CK-MB activity. Therefore, it is concluded that the NCS-DOX is effective against 4T1 cancer cells in vitro and in vivo, and less cardiotoxic than free DOX in vivo.
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Preserving a Legacy: The Dox Thrash House ProjectMalandra-Myers, Sam A. January 2022 (has links)
This thesis seeks to highlight the legacy of artist Dox Thrash as singular and crucial to Philadelphia’s historical narrative. This legacy includes not only his artwork, but the impact he made on the community around him, as well as the physical structure of his home on Cecil B. Moore Avenue. By examining the great oeuvre of Thrash’s artwork, this thesis argues that it is in need of recognition beyond what it has already received: not only because of the merit of the work, but because of the rarity of his perspective. Thrash depicted African American life in America with dignity and intimacy as a Black man at a time when the only mainstream representations currently circulating were in the form of caricatures and other insensitive portrayals by white artists. His work acts as a keystone to contextualize the Black experience in Philadelphia during the Jazz Era, even though the connection to that time has been seemingly under attack in this city.Sharswood, the neighborhood where Dox Thrash lived, was once a center of Black life, but has been dismantled and degraded by the effects of redlining. The state of his derelict home is emblematic of this, as it currently is marked with a historical placard from the city but did not have any preservation done to the structure. That is until the Dox Thrash House Project, a group of passionate volunteers, began to fundraise and raise awareness to save Thrash’s home. The work being done by the Dox Thrash House Project inspired this thesis as they have fought to bring Thrash’s home back to life through preservation. This thesis tackles the contextualization of the treatment of Thrash’s legacy within the current landscape of both art history and preservation in Philadelphia. / Art History / This thesis contains supplemental material that was not uploaded due to copyright restrictions. If you need to access the material, please contact the author directly. Accompanied by 1 PDF file: MalandraMyers_temple_0225M_171/List-of-figures.pdf
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Fluorous Nanoparticle Platform for Cancer Imaging and TreatmentWallat, Jaqueline Diane 02 February 2018 (has links)
No description available.
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Analýza účinnosti on-line komunikácie DOX / The analysis of efficiency of on-line communication of DOXČerná, Veronika January 2012 (has links)
The diploma thesis deals with the assessment of the effectiveness of on-line communication with the application for DOX Centre for Contemporary Art in Prague. It focuses on clarifying the theoretical framework of principles of social networks, mapping new trends and approaches in on-line communication and marketing. Part of the work is given to the identification of the percentage of the visitors of DOX who only search for information about exhibitions and other related program via the Internet. The emphasis is on research of the share of real customer of DOX to fan base on the Facebook social network. To make on-line communication more effective the priorities are set for various on-line channels with the tool for monitoring of mentions on the internet related to DOX. According to the fact that Facebook is an important interactive channel for DOX, there is created detailed analysis of the publications of contributions and the resulting recommendations for implementation. In conclusion, DOX expresses the contribution of the diploma thesis.
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Submillimeter wave absorption spectroscopy in the free jet environmentMelnik, Dmitry Georgievich 15 October 2003 (has links)
No description available.
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Drug Delivery with LightDupart, Patrick S 01 January 2018 (has links)
Cancer is responsible for about 25% of deaths in developed countries and for 15% of all deaths worldwide. Cancer is a devastating disease and while there have been great advances in the development of anticancer drugs, off-target toxicity is a major limitation with conventional cancer chemotherapy. The consequence of this form of treatment results in the killing of healthy and rapidly-growing non-cancerous cells including cells in the bone marrow; hair follicles; and cells in the mouth, digestive tract, and reproductive system. In addition to these general effects, certain anticancer drugs can have other associated toxicities. For instance, the anticancer drug doxorubicin (Dox), which my research has focused around, has dose-limiting cardiotoxicity. For these reasons, there has been much research focused on improving the selectivity of anticancer drugs in order to lower their toxicity to normal cells and decrease associated side effects. To circumvent the problem of non-selectivity, many methods have been developed to target cancer cells regionally at the site of the tumor. One such method is photodynamic therapy (PDT) which relies on a photosensitizer that is activated using light directed towards the tumor. Once activated, the photosensitizer creates singlet oxygen, which is cytotoxic to the illuminated tumor cells. PDT has shown profound effects in the treatment of many cancers including head and neck, lung, bladder, prostate, and esophagus. As PDT continues to be streamlined, it has the potential to serve as a standalone modality in the treatment and management of cancer at different stages. However, there are many inadequacies in the use of PDT. The fundamental problem lies in the inability of PDT to treat solid, bulky tumors or deep-seated tumors. This is partly due to the fact that current PS used cannot effectively kill cancer cells because with increasing tissue thickness the number of hypoxic cells increases. We have designed a new light based drug delivery which will allow for drugs to be released on the surface of the tumor, allowing the drug to freely diffuse through the tumor without the need of O2 and also, due to the manner our drug is attached, a more potent form the pre-attached drug is released. In this methodology, drug delivery will only be specific to an area of interest and the potential for side effects emerging from chemotherapy should be limited. Here we have shown, for the first time the generation of highly potent drug in a light dependent manner via a photocaging molecule and the commonly used chemotherapy agent Dox. We designed our photocage to generate a latent reactive form of Dox after illumination with UV light. This intermediate reacts in an intramolecular fashion to generate a highly potent form of the drug compared to its previous unattached form. Because of its high potency we have named the cleaved drug Super-Dox. Once the synthesis of the photocleavable drug conjugate was complete and we confirmed the photorelease of Super-Dox, via photolytic assay, and confirmed our drug conjugate is 80% cleaved from its photocage after 30 minutes of irritation with UV light. Next, we performed cell viability assays using MCF7 breast cancer cells to determine the efficiency of our drug conjugate to induce cell death. Our drug conjugate was able to induce significant cell death in the presence of light when compared to the dark. When compared to Dox, our cleaved drug conjugate is 26 folds more potent with light illumination an when compared to toxicity in the dark our drug conjugate was 374 fold less potent when conjugated to the photocage. However, our drug conjugate was not completely benign in the dark due to cell permeability, evidenced by confocal microscopy, we have worked equip our linker with sulfated cell impermeable group that will lower its background toxicity in the dark and allow us to achieve even higher enhancements in activity with light. This type of innovation creates a new avenue into cancer treatment which can limit adverse side effects and improve overall treatment.
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