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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Estabelecimento de linhagens tumorais para estudos in vitro e in vivo de carcinoma urotelial da bexiga e adenocarcinoma de próstata / Establishment of tumor cell lines from prostate adenocarcinoma and bladder urothelial carcinoma, for in vitro and in vivo studies

Camila Belfort Piantino 14 August 2009 (has links)
Introdução: Um dos principais obstáculos para compreensão dos eventos biológicos envolvidos no câncer é a falta de modelos adequados para o estudo in vitro em especial em relação ao câncer de próstata (CaP) e ao câncer de bexiga (CaB). Há um número limitado de linhagens celulares de CaP e de CaB sendo a maioria proveniente de tumores invasivos e metastáticos. Sabe-se ainda, que existem diferenças étnicas entre as populações quanto ao comportamento de neoplasias. Desta forma, a pesquisa baseada em linhagens de uma população homogênea seria fonte de resultados limitados, não contemplando a diversidade que sabidamente ocorre entre os diferentes grupos. Além desse aspecto, as linhagens celulares comerciais são na sua maioria adquiridas na Coleção Americana de Culturas de Tecido (ATCC, do inglês American Tissue Cell Culture) que apesar de serem bem padronizadas, requerem processos de importação com aumento do custo e demandas burocráticas que dificultam a pesquisa. Portanto, consideramos vital para a compreensão dos fenômenos relacionados à carcinogênese, assim como estudos de resistência a drogas, quimioprevenção e novas estratégias terapêuticas, o desenvolvimento de linhagens tumorais derivadas de tumores primários que acometem a nossa população, peculiarmente miscigenada. No presente trabalho, fragmentos de carcinoma urotelial da bexiga e de adenocarcinoma da próstata foram obtidos durante cirurgia para remoção de tumores primários de pacientes tratados e acompanhados na Divisão de Urologia da Faculdade de Medicina da Universidade de São Paulo (FMUSP) e no Hospital Sírio Libanês. As linhagens estabelecidas a partir destes fragmentos foram caracterizadas através da análise da cinética de crescimento, análises imunocitoquímicas e anormalidades cromossômicas incluindo cariótipo e hibridização in situ por fluorescência (FISH). Além disso, as linhagens obtidas foram submetidas a estudos de quimiossensibilidade com o uso dos compostos curcumin e Prima-1. Avaliamos ainda, a tumorigenicidade de nossas linhagens em camundongos atímicos. Os resultados deste trabalho demonstram o desenvolvimento de três linhagens de CaB e três linhagens de CaP sendo as mesmas não tumorigênicas em camundongos atímicos. Além disso, demonstramos que o curcumin na concentração de 50 M induziu morte celular em todas as linhagens estudadas, sendo seu efeito mais evidente nas linhagens de CaP. Por fim, Prima-1 reduziu a viabilidade celular independente do status de p53 nas linhagens de CaB / Introduction: One of the main obstacles for understanding biological events involved in cancer is the lack of appropriated models for in vitro studies especially for prostate cancer (PC) and bladder cancer (BC). There are a limited number of PC and BC cell lines being the majority originated from metastatic and invasive tumors. Also it is well known that there are ethnic differences between populations concerning the behavior of tumors. In such a way, the research based on cell lines derived from a homogenous population should be source of limited results, not contemplating the diversity known to occur among different groups. In addition the commercial cell lines are generally acquired at American Tissue Cell Culture (ATCC) that although wellestablished requires importation processes with cost increase and bureaucratic demands that difficult the research. Therefore we consider vital to the comprehension of the carcinogenesis phenomena, as well as drug resistance studies, chemoprevention and new therapeutic strategies, the development of tumor lineages derived from primary tumors that assail our miscigenated population. At the present work, fragments of bladder urothelial carcinoma and prostate adenocarcinoma were obtained by surgical resection of primary tumors from patients treated and followed in the Division of Urology of the Clinical Hospital of the São Paulo University (FMUSP) and Syrian Lebanese Hospital. The cell lines established from these fragments were characterized through growth kinetic, immunocytochemistry and chromosome abnormalities including karyotyping and Fluorescence in situ hybridization (FISH). Moreover, the cell lines were submitted to chemosensitivity studies using curcumin and Prima-1 and analyzed regarding their tumorigenicity in athymic mice. The results of this work show the development of three BC and three PC cell lines that were not tumorigenic in athymic mice. Curcumin at 50 M concentration induced cell death in all studied lineages, being more effective in PC cell lines. Finally, PRIMA-1 reduced the cellular viability independent of the p53 status in BC cell lines
82

Caracterização dos efeitos celulares e moleculares de NVP-BKM120, um inibidor de PI3K de classe I, em linhagens de leucemia linfoide e linfoma / Cellular and molecular characterization of NVP-BKM120, a class I PI3K inhibitor in lymphoma and lymphoid cell lines

Pereira, João Kleber Novais, 1980- 26 August 2018 (has links)
Orientadores: Patrícia Maria Bergamo Favaro, Sara Teresinha Olalla Saad / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-26T08:01:05Z (GMT). No. of bitstreams: 1 Pereira_JoaoKleberNovais_M.pdf: 3579832 bytes, checksum: 2f21cc28ac6161522a1ab6a958a04389 (MD5) Previous issue date: 2014 / Resumo: As neoplasias linfoides constituem um grupo heterogêneo de doenças originadas por alterações genéticas das células progenitoras hematopoéticas de origem linfoide, levando à proliferação clonal desordenada de células B ou T, e ao desenvolvimento de leucemias linfoides e linfomas. É notória a participação de diferentes vias de sinalização envolvidas tanto no desenvolvimento como na manutenção das neoplasias hematológicas. A ativação constitutiva da via de sinalização PI3K/AKT/mTOR é bem descrita na leucemia linfoide aguda de células T (LLA-T) e recentemente identificou-se, em modelos animais, que a atividade da PI3K coopera com o desenvolvimento do linfoma de Burkitt (LB). Deste modo, o papel da via PI3K/AKT/mTOR no crescimento e sobrevivência celular, duas características importantes da leucemogênese, transformou-a em um potencial alvo farmacológico. Seguindo essa perspectiva, o presente trabalho procurou avaliar o potencial terapêutico de NVP-BKM120, um pan-inibidor de PI3K de classe I, em linhagens celulares de LLA-T (Jurkat e MOLT-4) e LB (Daudi e NAMALWA). NVP-BKM120 foi capaz de diminuir a viabilidade celular e capacidade clonogênica dessas células. Foi observada uma parada na fase G2/M do ciclo celular, com subsequente diminuição de Ciclina B1 e aumento da apoptose pelas vias intrínseca e extrínseca, nas linhagens Jurkat, MOLT-4 e NAMALWA. Também foi observada diminuição da fosforilação da AKT e dos alvos downstream ao mTORC1, P70S6K e 4EBP1, e aumento da razão BAX:BCL2. Houve um aumento da produção de AVOs nas linhagens celulares após o tratamento com a droga, o que sugere ativação da autofagia. Portanto, este estudo demonstra a capacidade antitumoral de NVP-BKM120 contra linhagens celulares de LLA-T e LB. Nossos resultados sugerem que a diminuição da proliferação celular, após o tratamento com a droga, seja devido à redução da Ciclina B1 e que o aumento da razão BAX:BCL2 seja um dos mecanismos envolvidos na indução da apoptose / Abstract: The lymphoid neoplasms are a heterogeneous group of diseases caused by genetic alterations that were originated from hematopoietic progenitor cells of lymphoid origin, leading to uncontrolled clonal proliferation of B or T cells, and to the development of lymphoid leukemias and lymphomas. These findings emphasize the involvement of different signaling pathways involved in both the development and the maintenance of hematological malignancies. Constitutive activation of the PI3K /AKT/mTOR signaling pathway is well described for acute lymphoblastic leukemia T cells (T-ALL), recently been identified in animal models, that the activity of PI3K cooperates with the development of Burkitt's lymphoma (LB).Thus, the role of the PI3K / AKT / mTOR pathway in cell growth and survival, two important features of leukemogenesis, morphed into a potential drug target. Following this perspective, the present study aimed to evaluate the therapeutic potential of NVP-BKM120, a pan-PI3K inhibitor class I in cell lines of T-ALL (Jurkat and MOLT-4) and LB (Daudi and NAMALWA). NVP-BKM120 was able to decrease cell viability and clonogenic capacity of these cells. A blocked phase was observed in G2/M phase of the cell cycle with subsequent reduction of Cyclin B1 and increased apoptosis by the intrinsic and extrinsic pathways in the lines Jurkat and MOLT-4 NAMALWA. It was also observed, decreased phosphorylation of AKT and of the downstream targets mTORC1, p70S6K and 4EBP1, and an increase of BAX:BCL2 ratio. There was an increase in AVOs production in the cell lines after treatment with the drug, suggesting activation of autophagy. Therefore, this study demonstrates the antitumor ability of NVP-BKM120 against cell lines of T-ALL and LB. Our results suggest that the decrease in cell proliferation after treatment with the drug, is due to the reduction of Cyclin B1 and the increase of the BAX:BCL2 ratio is one of the mechanisms that are involved in the induction of apoptosis / Mestrado / Fisiopatologia Médica / Mestre em Ciências
83

Importance des glycoconjugués périphériques dans la différenciation myogénique : Rôle particulier de l'Ω (2,6) sialylation / Importance of peripheral glycoconjugates in myogenic differentiation : Special role of the (α2,6) sialylation

Bouchatal, Amel 08 April 2015 (has links)
Le développement du muscle squelettique est un processus complexe très finement régulé, qui inclus des étapes de prolifération de cellules progénitrices appelées myoblastes et des étapes de différenciation pour former des myotubes multi nucléés. La glycosylation est la principale modification post-traductionnelle des protéines. Son rôle dans divers processus biologiques et pathologiques est largement documenté, mais les mécanismes intimes de son implication lors du processus myogénique restent mal élucidés. Nous avons pris comme modèle cellulaire la lignée myoblastique C2C12 car elle est capable de mimer in vitro les étapes de prolifération et de différenciation de la cellule musculaire. En utilisant différentes lectines, nous montrons un changement de la sialylation périphérique en α2-6 des glycoconjugués de surface de la cellule C2C12 durant la différenciation myoblastique. En complément, nous avons analysé les N-glycannes des glycoprotéines par spectrométrie de masse et mesuré les niveaux d’expression des gènes des α2-6 sialyl-transférases et neuraminidases. Tous les résultats obtenus confirment bien que la différenciation des cellules C2C12 est accompagnée d’une diminution du taux de sialylation des glycoconjugués. Pour mieux comprendre l’implication de la sialylation en α2-6 dans la myogenèse, nous avons réalisé une étude fonctionnelle sur des cellules C2C12 qui sous-expriment St6gal1 du fait de l’introduction d’un shRNA spécifique. Les clones obtenus présentent de plus forts index de fusion et génèrent un plus grand nombre de myotubes qui, de surcroit, sont de grande taille. Ce phénotype est probablement dû à un engagement accru des cellules de réserve en différenciation. En effet, les clones sous-exprimant St6gal1 contiennent une plus petite proportion de cellules Pax7+, c’est-à-dire de cellules de réserve maintenues dans un état de quiescence.Ainsi, nos résultats montrent l’importante implication de la sialylation périphérique en α2-6 au cours de la différenciation myogénique. / Skeletal muscle development is a complex process highly regulated and which includes proliferation then differentiation of progenitor cells or myoblasts into multi-nucleated myotubes. Glycosylation is the main post-translational modification of proteins. Its role in various biological and pathological processes is well documented, but the precise mechanisms of its involvement during myogenesis are still poorly understood.We have used the C2C12 myoblast as a model cell line since it is able to mimic in vitro the steps of muscle cell proliferation and differentiation. Using different lectins we showed a change in the peripheral α2-6 sialylation of the cell surface glycoconjugates, during C2C12 differentiation. Besides, we also analyzed by mass spectrometry the N-glycans carried by glycoproteins and measured the expression levels of α2-6 sialyl-transferases and neuraminidases genes. All the results confirm that C2C12 differentiation is accompanied by a decrease of glycoconjugates sialylation. To highlight the involvement of α2-6 sialylation in myogenesis, we performed a functional study of C2C12 cells knockdown for St6gal1 by a specific shRNA. The generated clones exhibit a higher fusion index and generate more elongated myotubes. This phenotype probably results from an increased commitment of reserve cell in differentiation. Indeed, the clones knockdown for St6gal1 contain a lower proportion of Pax7+ cells, i.e. of reserve cells maintained in a quiescent state. Thus, our results show the significant involvement of the peripheral α2-6 sialylation during myogenic differentiation.
84

Cell line and protein engineering tools for production and characterization of biologics

Volk, Anna-Luisa January 2017 (has links)
Our increasing understanding of disease mechanisms coupled with technological advances has facilitated the generation of pharmaceutical proteins, which are able to address yet unmet medical needs. Diseases that were fatal in the past can now be treated with novel biological medications improving and prolonging life for many patients. Pharmaceutical protein production is, however, a complex undertaking, which is by no means problem-free. The demand for more complex proteins and the realization of the importance of post-translational modifications have led to an increasing use of mammalian cells for protein expression. Despite improvements in design and production, the costs required for the development of pharmaceutical proteins still are far greater than those for conventional, small molecule drugs. To render such treatments affordable for healthcare suppliers and assist in the implementation of precision medicine, further progress is needed. In five papers this thesis describes strategies and methods that can help to advance the development and manufacturing of pharmaceutical proteins. Two platforms for antibody engineering have been developed and evaluated, one of which allows for efficient screening of antibody libraries whilst the second enables the straightforward generation of bispecific antibodies. Moreover, a method for epitope mapping has been devised and applied to map the therapeutic antibody eculizumab’s epitope on its target protein. In a second step it was shown how this epitope information can be used to stratify patients and, thus, contribute to the realization of precision medicine. The fourth project focuses on the cell line development process during pharmaceutical protein production. A platform is described combining split-GFP and fluorescence-activated droplet sorting, which allows for the efficient selection of highly secreting cells from a heterogeneous cell pool. In an accompanying study, the split-GFP probe was improved to enable shorter assay times and increased sensitivity, desirable characteristics for high-throughput screening of cell pools. In summary, this thesis provides tools to improve design, development and production of future pharmaceutical proteins and as a result, it makes a contribution to the goal of implementing precision medicine through the generation of more cost-effective biopharmaceuticals for well-characterized patient groups. / <p>QC 20170828</p>
85

The Mutagenic Activity of High-Energy Explosives; Contaminants of Concern at Military Training Sites

McAllister, Jennifer E. January 2011 (has links)
The genotoxicity of energetic compounds (i.e., explosives) that are known to be present in contaminated soils at military training sites has not been extensively investigated. Thus, the Salmonella mutagenicity and Muta(TM)Mouse assays were employed as in vitro assays to examine the mutagenic activity of twelve explosive compounds, as well as three soil samples from Canadian Forces Base Petawawa. Salmonella analyses employed strains TA98 (frameshift mutations) and TA100 (base-pair substitution mutations), as well as the metabolically-enhanced YG1041 (TA98 background) and YG1042 (TA100 background), with and without exogenous metabolic activation (S9). For Salmonella analyses, the results indicate that ten of the explosive compounds were mutagenic, and consistently elicited direct-acting, base-pair substitution activity. All three soil samples were also observed to be mutagenic, eliciting direct-acting, frameshift activity. Mutagenic potencies were significantly higher on the metabolically-enhanced strains for all compounds and soil samples. For Muta(TM)Mouse analyses on FE1 cells, the results indicate that the majority of explosive compounds did not exhibit mutagenic activity. All three soil samples elicited significant positive responses (PET 1 and PET 3 without S9, and PET 2 with S9), and although there is some evidence of a concentration-related trend, the responses were weak. Correspondence of the mutagenic activity observed with the two assay systems, for both the explosive compounds and soil samples, was negligible. The differential response is likely due to differences in metabolic capacity between the two assay systems. Furthermore, it is likely that there are unidentified compounds present in these soil samples that are, at least in part, responsible for the observed mutagenic activity. Additional testing of other explosive compounds, as well as soil samples from other military training sites, using a variety of in vitro and in vivo assays, is warranted in order to reliably estimate mutagenic hazard and subsequently assess risk to human health.
86

Příprava HEK293 buněčné linie exprimující transportér auxinu PIN7 a testování inhibitorů přenosu auxinu / Preparation of HEK293 cell line expressing auxin transporter PIN7 and testing of inhibitors of auxin transport

Petermannová, Romana January 2015 (has links)
Auxin is one of the most important plant hormones, which provides development of a plant. PIN1 and PIN7 proteins belong to the PIN family of transporters which is among the most important auxin efflux carriers. This thesis deals with the of AtPIN1 and AtPIN7 auxin efflux carriers (from Arabidopsis thaliana) in human embryonic kidney 293 cell line. Biological activity of these proteins was tested by using radiolabeled auxins accumulation. Further inhibitors of auxin transport have been tested - NPA, CHPAA and BFA.
87

Establishment and characterization of a novel treatment-related neuroendocrine prostate cancer cell line KUCaP13 / 治療関連神経内分泌前立腺癌の新規細胞株KUCaP13の樹立とその特徴

Okasho, Kosuke 24 January 2022 (has links)
京都大学 / 新制・課程博士 / 博士(医学) / 甲第23601号 / 医博第4788号 / 新制||医||1055(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 羽賀 博典, 教授 戸井 雅和, 教授 伊藤 貴浩 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
88

Investigations of CHO 1-15 and Silk Gland Cell Line Development

Robinson, Susan Kathleen 01 May 2014 (has links)
The BioProcessing Demonstration and Training Laboratory was established with a collaboration between Utah State University and Thermo Fisher- Scientific, Inc. This lab was developed into a fully functioning tissue culture facility. Demonstration of tissue culture procedures were necessary for the lab to be industry-fully qualified. The CHO 1-15 cell line protocols were optimized by establishing conditions for reproducibility in shaker flasks and bioreactors (2 to 250 L capacity). CHO 1-15 is the cell line of choice for protein production in the bio-manufacturing industry. Oxidative stress is a problem in the industry because it can cause a decrease in protein production. Mesobiliverdin IXα and biliverdin IXα possess antioxidant capabilities. The effects of the antioxidant nature of these compounds were tested on the CHO 1-15 cell line. Cell cultures from silkworm and spider silk producing cells were also pursued. Methods to produce a primary cell line from spider silk gland cells were developed. Cell lines from spider and silkworm silk producing glands appeared to have the capacity to secrete full-length native proteins ranging in size from 200 to 500 kDa, and possibly larger.
89

Influence of Drying Method on NMR-based Metabolic Profiling of Human Cell Lines

Petrova, Irina 12 August 2019 (has links)
No description available.
90

Charakterizace nově vyvinutých fluorescenčních sond v buněčných systémech / Characterization of newly developed fluorescence probes in cellular systems

Kadlecová, Julie January 2021 (has links)
Nanoparticles (NP) are currently a progressive area of scientific research. The possibility of synthesizing them according to the required parameters opens up possibilities for their wide use also in biomedicine. One example is a nanoparticle that can detect cellular processes, such as pH. We already know that the pH of healthy and cancer cells differs by the opposite gradient on the intracellular and extracellular side of the membrane. In this context, this work deals with the study of fluorescent silicon nanoparticles (SiNP) tested on a human keratinocyte cell line from a healthy donor (HaCaT) and from skin cancer donor (A431). Once found that even the highest concentrations of SiNP used are not cytotoxic, they can be further studied by fluorescence, confocal and super-resolution microscopy. In order to assess the pH detection properties of these SiNPs, a method for measuring intracellular pH with a fluorescent raciometric probe SNARF-1 using fluorescence spectroscopy and flow cytometry was introduced. Since the pH values of the intracellular environment are closely related to cellular metabolism, the metabolism of A431 and HaCaT cells was characterized and compared. To do this, methods for measuring analog glucose consumption (2-NBDG) and another new method for measuring real-time metabolism...

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