455 research outputs found

    Evaluation of fibroblast growth factor receptors as therapeutic targets in melanoma

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    Das Melanom ist die tötlichste Hautkrebsart und ist in einem fortgeschrittenen Stadium schwierig zu behandeln. Fibroblasten Wachstumsfaktoren (FGF1-23) und deren Rezeptoren (FGFR1-4) sind beteiligt an Tumorwachstum, Angiogenese und Überleben von malignen Zellen bei verschiedensten Tumorarten. Eine krebs-stimulierende Rolle im speziellen beim Melanom, wurde fĂŒr die Wachstumsfaktoren FGF-1 (aFGF) und FGF-2 (bFGF), sowie den FGF Rezeptor FGFR-1 nachgewiesen. Außerdem wurde eine Korrelation, zwischen der FGFR-4 Protein Expression und dem Überleben von Melanom-Patienten, beschrieben. Es wird auch angenommen, dass der kĂŒrzlich identifizierte Arg/Gly Polymorphismus von FGFR-4, die Progression und Zell Migration von einigen Krebsarten stimuliert. Ziele: Die Ziele waren (A) eine Evaluierung des Potenzials von FGF-Rezeptoren als therapeutische “Targets” in der Melanombehandlung, und (B) die Untersuchung des FGFR-4 Arg/Gly Polymorphismus und seine möglichen Auswirkungen auf Melanom Zelllinien. Methoden: Die Methoden umfassten, (I) eine Expressionsanalyse von allen FGF-Rezeptoren, sowie deren verschiedenen Isoformen und allen 22 humanen FGF-Liganden mittels Standard PCR und qRT-PCR, (II) Analyse der zellulĂ€ren Effekte durch Blockierung des FGFR Signals mittels dominant-negativer Rezeptor Konstrukte, (III) Untersuchung der Effekte von FGFR Blockierung auf das Tumorwachstum In Vivo mittels Xenotransplantationsexperimente in SCID MĂ€usen, (IV) Analyse der Auswirkungen von niedermolekularen FGFR Inhibitoren, im Vergleich zu FGF-2 Stimulation, auf den FGFR Signalweg, (V) Untersuchung von 41 Melanomproben hinsichtlich FGFR-4 Arg/Gly Expressionsmuster und Vergleich mit der Progressionsstufe des Tumors, (VI) Analyse der Effekte des FGFR-4 Arg Allels auf die Zellmigration und Proliferation. Resultate: Die Expressionsanalyse zeigte, dass der FGFR-1 und der FGFR-4 in nahezu allen Melanom Zelllinien stark exprimiert werden, im Vergleich zu FGFR-2 und FGFR-3. Nimmt man jedoch primĂ€re Melanozyten als Referenz, so scheint ausschließlich die Expression von FGFR-4 und FGFR-2 hinaufreguliert, wĂ€hrend die Expression von FGFR-1 auf einem hohen Niveau bestehen, und FGFR-3 unverĂ€ndert niedrig, bleibt. Im Allgemeinen, ist die Expression der FGF-Rezeptoren und deren Isoformen sehr heterogen ausgefallen, vergleicht man das Expressionsmuster der Zelllinien untereinander. VerkĂŒrzte FGFR Isoformen und Isoformen ohne TransmembrandomĂ€ne, wurden nur in rund der HĂ€lfte der untersuchten Zelllinien nachgewiesen. Betrachtet man die Expression der FGF Liganden, so wurde gezeigt, dass FGF-2 in allen untersuchten Melanomzelllinien sehr stark exprimiert wird, im Gegensatz zu primĂ€ren Melanozyten. FGF-5 wurde in der Mehrheit der Zelllinien (90%) exprimiert, wĂ€hrend die Expression von FGF-18 in ungefĂ€hr 40% hinaufreguliert war und das Expressionsniveau von FGF-17 und FGF-8 in allen Zelllinien durchwegs niedrig ausfiel. Eine Inhibierung der FGF-Rezeptoren durch dominant-negative FGFR Konstrukte zeigte, dass eine Blockierung des FGFR-1 Signalweges ein vielversprechender therapeutischer Ansatz beim Melanom ist. Eine „In Vitro“ Inhibierung wurde mittels, Proliferations-, KlonogenizitĂ€ts- und Soft Agar- Experimente, getestet. Resultate wurden anschließend „In Vivo“, durch Xenotransplantation von Melanomzellen in SCID MĂ€use, bestĂ€tigt. Weiters wurde gezeigt, dass eine Inhibierung des FGFR-1 Signalweges in Melanomzellen Apoptose induziert. Dies konnte einerseits durch Fluoreszenz-Mikroskopie und Propidiumjodid FĂ€rbung verfolgt werden und wurde schließlich auch mittels Western-Blot Analyse bestĂ€tigt. Es wurde gezeigt, dass die Zellvermehrung um ca. 20-40% zunahm, wenn Melanomzellen mit FGF-2 stimuliert wurden. Die IntensitĂ€t stimulatorischer Effekte war abhĂ€ngig vom endogenen Expressionsniveau. Zelllinien mit niedriger FGF-2 Expression konnten leichter mit zusĂ€tzlichem FGF-2 stimuliert werden. Auch die MigrationsfĂ€higkeit der Melanomzelllinien konnte um 20-50% erhöht werden, wenn FGF-2 oder FGF-5 zugegeben wurde. Die StĂ€rke der Stimulation durch FGF-2 oder FGF-5, war auch hier von der Eigenproduktion abhĂ€ngig. Weiters wurde demonstriert, dass der MAPK- und Akt- Signalweg durch FGF-2 stimuliert werden kann. Aber auch, dass eine vorhergehende Blockierung der FGF-Rezeptoren, durch „Small Molecule Inhibitors“ (PD166866 und SU5402), diese Stimulation verhindert. Eine Blockierung von Signalwegen durch diese Inhibitoren, ohne vorherige Stimulation durch FGF-2, konnte jedoch nicht gezeigt werden. Eine homozygote Expression des FGFR-4 Gly388 Allels nahm mit zunehmender Krebsprogression deutlich ab (PrimĂ€rtumore: 65%; Metastasen: 42% und maligne Effusionen: 20%). Ein Einfluss des FGFR-4 Arg388 Allels auf die Progression im Melanom ist daher naheliegend. Bei der Untersuchung von Zellmigration und Proliferation, mittels stabiler Expression des FGFR-4 Arg388 versus Gly388 Allel in Melanomzelllinien, wurde gezeigt, dass die Zellproliferation zwischen den Allelen unverĂ€ndert bleibt, die Migration in einer von zwei Arg388 Zelllinien aber 2.5 fach zunimmt. Schlussfolgerungen: In Vivo, sowie In Vitro, wurde gezeigt, dass die Zellproliferation bzw. das Tumorwachstum um 50% reduziert wird, wenn der FGFR-1 Signalweg durch adenovirale dnFGFR1 Konstrukte inhibiert wird. Als Referenz wurden Zellen, anstatt mit dnFGFR1, mit GFP Konstrukten infiziert. Unsere Untersuchungen legen eine therapeutische Blockierung des FGFR-1 nahe. Weiters kann man daraus schließen, dass das FGFR-4 Arg388 Allel möglicherweise zur Progression von Melanomen beitrĂ€gt.Melanoma is the most deadly cutaneous malignancy and is difficult to treat at the advanced stage. Fibroblast Growth Factors (FGF1-23) and Fibroblast Growth Factor Receptors (FGFR1-4) are critically involved in tumour cell growth, survival and angiogenesis of several tumour types. In melanoma several reports have established an oncogenic role of acidic FGF (FGF-1), basic FGF (FGF-2) and FGFR1. Besides, a correlation between FGFR-4 protein expression and survival of melanoma patients has been described. The recently identified Arg/Gly polymorphism of FGFR-4 is suggested to influence cancer progression and cell migration of various tumour types. Objectives: The purpose of the study was (A) to evaluate the potential of FGFRs as molecular therapy targets for melanoma and (B) to investigate putative cellular effects of the FGFR-4 Arg/Gly polymorphism in melanoma cell lines. Methods: The thesis included (I) expression analysis in a panel of melanoma cell lines of all four FGFRs including different isoforms, and all 22 FGFs, by standard PCR and qRT-PCR, (II) analysis of cellular effects of blockade of FGFR signals by dominant-negative receptor constructs, (III) the effect of FGFR blockade on tumour growth in vivo by xenotransplantation experiments in SCID mice, (IV) the effect of small molecule FGFR inhibitors, versus FGF-2 stimulation on downstream signalling, (V) effects of FGF-2 on cell migration and proliferation, (V) investigation of 41 melanoma samples for FGFR-4 Arg/Gly expression and comparison with clinical stage, (VI) effects of the FGFR-4 Arg388 allele on cell migration and proliferation. Results: Expression analysis revealed, that FGFR-1 and FGFR-4 are highly expressed in nearly all melanoma cell lines, compared to FGFR-2 and FGFR-3. Taking non-transformed melanocytes as reference, the expression of FGFR-4 and FGFR-2 seems to be highly up-regulated in nearly all melanoma cell lines, while expression of FGFR-1 is maintained on a high level and FGFR-3 stays low. In general, expression levels of all FGFRs and isoforms were heterogeneous. Truncated FGFR isoforms, especially those lacking the TM-domain, were not detected in around half of the melanoma cell lines. Considering expression of FGF ligands, FGF-2 was found to be highly up-regulated in all melanoma cell lines investigated while FGF-5 was up-regulated in the vast majority (90%). Expression of FGF18 was found up-regulated in 40% and FGF-17 and FGF-8 stayed low in all cell lines. Similar to FGF-Receptors, ligands were also expressed in a heterogeneous manner. Inhibition of FGFRs by expression of dominant-negative FGFR constructs revealed, that blockade of the FGFR-1 pathway seems to be an effective therapeutic approach in melanoma cells. In vitro inhibition was tested by proliferation assays, clonogenic assays, and soft agar assays. Results have been confirmed in vivo, by xenotransplantation experiments in SCID mice. It has been shown, by blocking the FGFR-1 pathway, that melanoma cell lines induce apoptosis. This was monitored by fluorescence microscopy and propidium-iodide staining, and finally verified by immune-blotting determining protein levels of cleaved PARP1 and Caspase 3. Cell proliferation was increased around 20-40% when cells were stimulated with exogenous FGF-2. Intensity of stimulatory effects depended on endogenous FGF-2 expression levels. Thus, cell lines with low FGF-2 expression levels were more easily stimulated. Migration of melanoma cells was also stimulated about 20-50%, either by exogenous FGF-2 or FGF-5. Migration of cells having low endogenous FGF-2 or FGF-5 expression was more easily stimulated. The MAPK- and Akt- signalling pathways were shown to be stimulated by FGF-2. Prior incubation with FGFR small molecule inhibitors, PD166866 and SU5402, prevented stimulation by FGF-2. However, inhibition of constitutive activation of downstream signals by small-molecule FGFR inhibitors alone, could not be shown in this study. Homozygous expression of the FGFR-4 Gly388 allele was found to be reduced with increasing cancer stage (primary tumours: 62%; metastases: 43%; malignant effusions: 20%), in melanoma cell lines. Therefore, the FGFR-4 Arg388 allele is suggested to be involved in cancer progression of melanoma. Investigating cell migration and proliferation, using stably expressing FGFR-4 Arg388 versus Gly388 cell lines, revealed no differences considering cell proliferation, but migration was increased 2.5 x in one of two FGFR Arg388 cell lines. Conclusion: In Vivo as well as in vitro, cell proliferation or tumour growth is reduced to about 50%, when infected with adenoviruses bearing dnFGFR1 constructs, compared to GFP as control. Our investigation suggests that FGFR-1 inhibition might be a promising strategy for melanoma therapy. The FGFR-4 Arg388 allele might contribute to melanoma progression

    ESTILO DE VIDA DOS CLIENTES DA CLÍNICA DE ESTÉTICA LA FEME DE MARECHAL CÂNDIDO RONDON/PR

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    Este estudo teve por objetivo verificar o perfil do estilo de vida dos clientes freqüentadores da Clínica de Estética La Feme de Marechal Cândido Rondon – Pr, considerando seis fatores (Nutrição, Atividade física, Comportamento preventivo, Relacionamento social, Controle de stress e Espiritualidade), individuais relacionados ao bem estar. Foram avaliadas 30 clientes na faixa etária de 18 a 57 anos. Para coleta das informações utilizou-se do questionário perfil do estilo de vida, e a análise dos dados foram realizados mediante estatística descritiva, para tanto utilizou - se do programa SSPS. Mediante os resultados obtidos, pode inferir-se que nos componentes hábitos alimentares e de atividades físicas das clientes da Clínica de Estética La Feme, as mesmas apresentam um comportamento saudável. Quanto ao comportamento preventivo e o relacionamento social o resultado encontrado foi considerado bom, revelando que pessoas bem informadas, são mais suscetíveis a atitudes favoráveis e à mudanças comportamentais relacionadas a um estilo de vida ideal. No controle do stress a amostra pesquisada demonstrou reservar tempo para relaxar, e equilibrar o tempo de lazer com o tempo dedicado ao trabalho. As respostas obtidas no componente da espiritualidade nos mostram que cada vez mais as pessoas tem buscado reservar tempo para ir à igreja e se aproximar das coisas de Deus, e principalmente encontrando forças para perdoar o próximo. Mediante estes resultados, percebe-se que nossas escolhas e decisões, ou seja, o nosso estilo de vida, revela a maneira como vivemos e o tempo de vida que ainda teremos

    HIV-1 diversity in viral reservoirs obtained from circulating T-cell subsets during early ART and beyond

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    Even during extended periods of effective immunological control, a substantial dynamic of the viral genome can be observed in different cellular compartments in HIV-1 positive individuals, indicating the persistence of active viral reservoirs. To obtain further insights, we studied changes in the proviral as well as in the viral HIV-1 envelope (Env) sequence along with transcriptional, translational and viral outgrowth activity as indicators for viral dynamics and genomic intactness. Our study identified distinct reservoir patterns that either represented highly sequence-diverse HIV-1 populations or only a single / few persisting virus variants. The single dominating variants were more often found in individuals starting ART during early infection phases, indicating that early treatment might limit reservoir diversification. At the same time, more sequence-diverse HIV reservoirs correlated with a poorer immune status, indicated by lower CD4 count, a higher number of regimen changes and more co-morbidities. Furthermore, we noted that in T-cell populations in the peripheral blood, replication-competent HIV-1 is predominantly present in Lymph node homing TN (naĂŻve) and TCM (central memory) T cells. Provirus genomes archived in TTM (transitional memory) and TEM (effector memory) T cells more frequently tended to carry inactivating mutations and, population-wise, possess changes in the genetic diversity. These discriminating properties of the viral reservoir in T-cell subsets may have important implications for new early therapy strategies, underscoring the critical role of early therapy in preserving robust immune surveillance and constraining the viral reservoir

    AnsĂ€tze zur nachhaltigen Sicherung der botanischen Artenvielfalt auf SchutzĂ€ckern – eine Aufgabe fĂŒr Biobetriebe?

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    Der drastische ArtenrĂŒckgang unter den AckerwildkrĂ€utern war Anlass zur Suche nach neuen Schutzkonzepten. Das Projekt „Errichtung eines bundesweiten Schutzgebietsnetzes fĂŒr AckerwildkrĂ€uter“ verfolgt das Ziel, ein nachhaltiges Schutzgebiets-Netzwerk zum Erhalt bedrohter Segetalarten in Deutschland zu konzipieren und umzusetzen. Eine Anzahl von mindestens 100 geeigneten Ackerstandorten („100 Äcker fĂŒr die Vielfalt“) soll fĂŒr eine „dauerhafte Sicherung“ selten gewordener AckerwildkrĂ€uter unter Schutz gestellt werden und ihre spezielle, auf den Erhalt und Förderung der entsprechenden Arten ausgerichtete Bewirtschaftung langfristig sichergestellt werden. Ökologisch bewirtschaftete Felder sind dazu besonders geeignet. Das innovative Beispiel eines ökologisch wirtschaftenden Landwirts wird vorgestellt. Die Herausforderung ist die Sicherstellung des langfristigen Schutzes durch vertragliche Vereinbarungen

    Editorial: Advances in Computational Neuroscience

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    © 2022 Nowotny, van Albada, Fellous, Haas, Jolivet, Metzner and Sharpee. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). https://creativecommons.org/licenses/by/4.0/Peer reviewedFinal Published versio

    Implementation of GENFIT2 as an experiment independent track-fitting framework

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    The GENFIT toolkit, initially developed at the Technische Universitaet Muenchen, has been extended and modified to be more general and user-friendly. The new GENFIT, called GENFIT2, provides track representation, track-fitting algorithms and graphic visualization of tracks and detectors, and it can be used for any experiment that determines parameters of charged particle trajectories from spacial coordinate measurements. Based on general Kalman filter routines, it can perform extrapolations of track parameters and covariance matrices. It also provides interfaces to Millepede II for alignment purposes, and RAVE for the vertex finder. Results of an implementation of GENFIT2 in basf2 and PandaRoot software frameworks are presented here.Comment: 41 pages 24 figures, 1 table. Paper submitted to NI

    The Full Event Interpretation -- An exclusive tagging algorithm for the Belle II experiment

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    The Full Event Interpretation is presented: a new exclusive tagging algorithm used by the high-energy physics experiment Belle II. The experimental setup of Belle II allows the precise measurement of otherwise inaccessible BB meson decay-modes. The Full Event Interpretation algorithm enables many of these measurements. The algorithm relies on machine learning to automatically identify plausible BB meson decay chains based on the data recorded by the detector. Compared to similar algorithms employed by previous experiments, the Full Event Interpretation provides a greater efficiency, yielding a larger effective sample size usable in the measurement.Comment: 11 pages, 7 figures, 1 tabl

    Optical Conductivity in Mott-Hubbard Systems

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    We study the transfer of spectral weight in the optical spectra of a strongly correlated electron system as a function of temperature and interaction strength. Within a dynamical mean field theory of the Hubbard model that becomes exact in the limit of large lattice coordination, we predict an anomalous enhancement of spectral weight as a function of temperature in the correlated metallic state and report on experimental measurements which agree with this prediction in V2O3V_2O_3. We argue that the optical conductivity anomalies in the metal are connected to the proximity to a crossover region in the phase diagram of the model.Comment: 12 pages and 4 figures, to appear in Phys. Rev. Lett., v 75, p 105 (1995

    Ferromagnetism in the large-U Hubbard model

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    We study the Hubbard model on a hypercubic lattice with regard to the possibility of itinerant ferromagnetism. The Dynamical Mean Field theory is used to map the lattice model on an effective local problem, which is treated with help of the Non Crossing Approximation. By investigating spin dependent one-particle Green's functions and the magnetic susceptibility, a region with nonvanishing ferromagnetic polarization is found in the limit U→∞U\to\infty. The ή\delta-T-phase diagram as well as thermodynamic quantities are discussed. The dependence of the Curie temperature on the Coulomb interaction and the competition between ferromagnetism and antiferromagnetism are studied in the large UU limit of the Hubbard model.Comment: 4 pages, 5 figures, accepted for publication in Physical Review B, Rapid Communication
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