6 research outputs found

    Depositing Molecular Graphene Nanoribbons on Ag(111) by Electrospray Controlled Ion Beam Deposition: Self-Assembly and On-Surface Transformations

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    The chemical processing of low-dimensional carbon nanostructures is crucial for their integration in future devices. Here we apply a new methodology in atomically precise engineering by combining multistep solution synthesis of N-doped molecular graphene nanoribbons (GNRs) with mass-selected ultra-high vacuum electrospray controlled ion beam deposition on surfaces and real-space visualisation by scanning tunnelling microscopy. We demonstrate how this method yields solely a controllable amount of single, otherwise unsublimable, GNRs of 2.9 nm length on a planar Ag(111) surface. This methodology allows for further processing by employing on-surface synthesis protocols and exploiting the reactivity of the substrate. Following multiple chemical transformations, the GNRs provide reactive building blocks to form extended, metal-organic coordination polymers.This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreements No. 946223 and No. 899895. Financial support was provided by the German Research Foundation (DFG) through the TUM International Graduate School of Science and Engineering (IGSSE), Excellence Cluster e-conversion, and the priority programme 1928 COORNETs, the China Scholarship Council (CSC) and the European Research Council (ERC) (no. 722951). This project has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (Grant Agreement No. 722951). This work was carried out with support from the Basque Foundation for Science (Ikerbasque), POLYMAT, the University of the Basque Country, Gobierno Vasco (BERC programme). Technical and human support provided by SGIker of UPV/EHU and European funding (ERDF and ESF) is acknowledged. Open Access funding enabled and organized by Projekt DEAL

    STAT3/LKB1 controls metastatic prostate cancer by regulating mTORC1/CREB pathway

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    Prostate cancer (PCa) is a common and fatal type of cancer in men. Metastatic PCa (mPCa) is a major factor contributing to its lethality, although the mechanisms remain poorly understood. PTEN is one of the most frequently deleted genes in mPCa. Here we show a frequent genomic co-deletion of PTEN and STAT3 in liquid biopsies of patients with mPCa. Loss of Stat3 in a Pten-null mouse prostate model leads to a reduction of LKB1/pAMPK with simultaneous activation of mTOR/CREB, resulting in metastatic disease. However, constitutive activation of Stat3 led to high LKB1/pAMPK levels and suppressed mTORC1/CREB pathway, preventing mPCa development. Metformin, one of the most widely prescribed therapeutics against type 2 diabetes, inhibits mTORC1 in liver and requires LKB1 to mediate glucose homeostasis. We find that metformin treatment of STAT3/AR-expressing PCa xenografts resulted in significantly reduced tumor growth accompanied by diminished mTORC1/CREB, AR and PSA levels. PCa xenografts with deletion of STAT3/AR nearly completely abrogated mTORC1/CREB inhibition mediated by metformin. Moreover, metformin treatment of PCa patients with high Gleason grade and type 2 diabetes resulted in undetectable mTORC1 levels and upregulated STAT3 expression. Furthermore, PCa patients with high CREB expression have worse clinical outcomes and a significantly increased risk of PCa relapse and metastatic recurrence. In summary, we have shown that STAT3 controls mPCa via LKB1/pAMPK/mTORC1/CREB signaling, which we have identified as a promising novel downstream target for the treatment of lethal mPCa

    Navigate flying molecular elephants safely to the ground: mass-selective soft landing up to the Mega-Dalton range by Electrospray Controlled Ion-Beam Deposition

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    The prototype of a highly versatile and efficient preparative mass spectrometry system used for the deposition of molecules in ultra-high vacuum (UHV) is presented, along with encouraging performance data obtained on four model species which are thermolabile or not sublimable. The test panel comprises two small organic compounds, a protein, and a large DNA species covering a 4-log mass range up to 1.7 MDa as part of a broad spectrum of analyte species evaluated to date. Three designs of innovative ion guides, a novel digital mass-selective quadrupole (dQMS) and a standard electrospray ionization (ESI) source are combined to an integrated device, abbreviated Electrospray Controlled Ion Beam Deposition (ES-CIBD). Full control is achieved by i) the square-wave-driven radiofrequency (RF) ion guides with steadily tunable frequencies, including a dQMS allowing for investigation, purification and deposition of a virtually unlimited m/z range, ii) the adjustable landing energy of ions down to ~2 eV/z enabling integrity-preserving soft-landing, iii) the deposition in UHV with high ion beam intensity (up to 3 nA) limiting contaminations and deposition time, and iv) direct coverage control via the deposited charge. The maximum resolution of R=650 and overall efficiency up to T_total=4.4% calculated from solution to UHV deposition are remarkable as well, while the latter is mainly limited by the not yet optimized ionization performance. In the setup presented, a scanning tunneling microscope (STM) is attached for in situ UHV investigation of the deponents demonstrating a selective, structure-preserving process and atomically clean layers

    Marktuebersicht dezentrale Holzvergasung: Marktanalyse 2000 fuer Holzvergasersysteme bis 5 MW

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    Dual-purpose power systems utilizing wood gas (from wood wastes, wood chips, used wood, etc.) as a fuel is an interesting way of using biomass efficiently. Many fields of application which can be implemented are known. There is one thing that makes this clean technology fail although at first sight it seems to be very efficient: the system 'wood gas-dural purpose power plants' is not mature for the market yet, i.e. it lacks the plant-technologies. this report is built up on the studies made by the Oeco-Institute about this subject and other similar studies in order to give a general view at the market of wood gasifiers and wood gas-dual purpose power plants.Kraft-Waerme-Kopplung mit Holzgas (aus Holzresten, Holzschnitzeln, Altholz, etc.) als Brennstoff ist eine interessante Moeglichkeit zur effizienten Nutzung von Biomasse. Eine Reihe von Anwendungsfeldern sind hierfuer bekannt, die aussichtsreich umgesetzt werden koennten. Woran diese auf den ersten Anblick sehr effiziente und saubere Technologie scheitert, ist die fehlende Marktreife der Systems 'Holzgas-BHKW', also der Integration von Vergasertechnik mit BHKW-Technologien. Diese Arbeit knuepft an bisherige Studien des Oeko-Instituts zu diesem Thema sowie andere vergleichbare Studien an, um eine aktuelle Uebersicht ueber den Markt von Holzvergasern und Holzgas-BHKW geben. (orig.)SIGLEAvailable from: <a href=http://www.oeko.de target=NewWindow>http://www.oeko.de</a> / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

    JUN mediates the senescence associated secretory phenotype and immune cell recruitment to prevent prostate cancer progression

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    Background: Prostate cancer develops through malignant transformation of the prostate epithelium in a stepwise, mutation-driven process. Although activator protein-1 transcription factors such as JUN have been implicated as potential oncogenic drivers, the molecular programs contributing to prostate cancer progression are not fully understood. Methods: We analyzed JUN expression in clinical prostate cancer samples across different stages and investigated its functional role in a Pten-deficient mouse model. We performed histopathological examinations, transcriptomic analyses and explored the senescence-associated secretory phenotype in the tumor microenvironment. Results: Elevated JUN levels characterized early-stage prostate cancer and predicted improved survival in human and murine samples. Immune-phenotyping of Pten-deficient prostates revealed high accumulation of tumor-infiltrating leukocytes, particularly innate immune cells, neutrophils and macrophages as well as high levels of STAT3 activation and IL-1β production. Jun depletion in a Pten-deficient background prevented immune cell attraction which was accompanied by significant reduction of active STAT3 and IL-1β and accelerated prostate tumor growth. Comparative transcriptome profiling of prostate epithelial cells revealed a senescence-associated gene signature, upregulation of pro-inflammatory processes involved in immune cell attraction and of chemokines such as IL-1β, TNF-α, CCL3 and CCL8 in Pten-deficient prostates. Strikingly, JUN depletion reversed both the senescence-associated secretory phenotype and senescence-associated immune cell infiltration but had no impact on cell cycle arrest. As a result, JUN depletion in Pten-deficient prostates interfered with the senescence-associated immune clearance and accelerated tumor growth. Conclusions: Our results suggest that JUN acts as tumor-suppressor and decelerates the progression of prostate cancer by transcriptional regulation of senescence- and inflammation-associated genes. This study opens avenues for novel treatment strategies that could impede disease progression and improve patient outcomes. Graphical Abstract: (Figure presented.)

    JUN mediates the senescence associated secretory phenotype and immune cell recruitment to prevent prostate cancer progression

    No full text
    Prostate cancer develops through malignant transformation of the prostate epithelium in a stepwise, mutation-driven process. Although activator protein-1 transcription factors such as JUN have been implicated as potential oncogenic drivers, the molecular programs contributing to prostate cancer progression are not fully understood.We analyzed JUN expression in clinical prostate cancer samples across different stages and investigated its functional role in a Pten-deficient mouse model. We performed histopathological examinations, transcriptomic analyses and explored the senescence-associated secretory phenotype in the tumor microenvironment.Elevated JUN levels characterized early-stage prostate cancer and predicted improved survival in human and murine samples. Immune-phenotyping of Pten-deficient prostates revealed high accumulation of tumor-infiltrating leukocytes, particularly innate immune cells, neutrophils and macrophages as well as high levels of STAT3 activation and IL-1? production. Jun depletion in a Pten-deficient background prevented immune cell attraction which was accompanied by significant reduction of active STAT3 and IL-1? and accelerated prostate tumor growth. Comparative transcriptome profiling of prostate epithelial cells revealed a senescence-associated gene signature, upregulation of pro-inflammatory processes involved in immune cell attraction and of chemokines such as IL-1?, TNF-?, CCL3 and CCL8 in Pten-deficient prostates. Strikingly, JUN depletion reversed both the senescence-associated secretory phenotype and senescence-associated immune cell infiltration but had no impact on cell cycle arrest. As a result, JUN depletion in Pten-deficient prostates interfered with the senescence-associated immune clearance and accelerated tumor growth.Our results suggest that JUN acts as tumor-suppressor and decelerates the progression of prostate cancer by transcriptional regulation of senescence- and inflammation-associated genes. This study opens avenues for novel treatment strategies that could impede disease progression and improve patient outcomes
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