0000000000088314

AUTHOR

Leonard Kaps

Ferrocenyl-Coupled N-Heterocyclic Carbene Complexes of Gold(I)

Four gold(I) carbene complexes featuring 4-ferro-cenyl-substituted imidazol-2-ylidene ligands were investigated for antiproliferative and antivascular properties. They were active against a panel of seven cancer cell lines, including multidrug-resistant ones, with low micromolar or nanomolar IC50 (72 h) values, according to their lipophilicity and cellular uptake. The delocalized lipophilic cationic complexes 8 and 10 acted by increasing the reactive oxygen species in two ways: through a genuine ferrocene effect and by inhibiting the thioredoxin reductase. Both complexes gave rise to a reorganization of the F-actin cytoskeleton in endothelial and melanoma cells, associated with a G1 phase c…

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Generation and validation of syngeneic murine hepatoma cells bearing features of human HCC for rapid anti-HCC drug screening

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Cylindrical Brush Polymers with Polysarcosine Side Chains: A Novel Biocompatible Carrier for Biomedical Applications

Cylindrical brush polymers constitute promising polymeric drug delivery systems (nanoDDS). Because of the densely grafted side chains such structures may intrinsically exhibit little protein adsorption (“stealth” effect) while providing a large number of functional groups accessible for bioconjugation reactions. Polysarcosine (PSar) is a highly water-soluble, nonionic and nonimmunogenic polypeptoid based on the endogenous amino acid sarcosine (N-methyl glycine). Here we report on the synthesis, characterization and biocompatibility of cylindrical brush polymers with either polysarcosine side chains or poly-l-lysine-b-polysarcosine side chains. The latter leads to block copolypept(o)id based…

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Squaric Ester-Based, pH-Degradable Nanogels: Modular Nanocarriers for Safe, Systemic Administration of Toll-like Receptor 7/8 Agonistic Immune Modulators

Small-molecular Toll-like receptor 7/8 (TLR7/8) agonists hold promise as immune modulators for a variety of immune therapeutic purposes including cancer therapy or vaccination. However, due to their rapid systemic distribution causing difficult-to-control inflammatory off-target effects, their application is still problematic, in particular systemically. To address this problem, we designed and robustly fabricated pH-responsive nanogels serving as versatile immunodrug nanocarriers for safe delivery of TLR7/8-stimulating imidazoquinolines after intravenous administration. To this aim, a primary amine-reactive methacrylamide monomer bearing a pendant squaric ester amide is introduced, which i…

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SiRNA-mediated in vivo gene knockdown by acid-degradable cationic nanohydrogel particles

Cationic nanohydrogel particles have become an attractive tool for systemic siRNA delivery, but improvement of their in vivo tolerance is desirable, especially to prevent potential long term side effects by tissue and cellular accumulation. Here, we designed novel ketal cross-linked cationic nanohydrogel particles that were assessed for reduced tissue accumulation and robust siRNA delivery in vitro and in vivo. An oligo-amine cross-linker equipped with a ketal moiety in its core was synthesized and applied to nanohydrogel cross-linking of self-assembled reactive ester block copolymers in DMSO. The resulting acid-sensitive cationic nanoparticles spontaneously disassembled over time in acidic…

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Non-alcoholic fatty liver disease increases the risk of incident chronic kidney disease

BACKGROUND AND AIM: Non-alcoholic fatty liver disease (NAFLD) is a highly prevalent chronic liver disease. Its role in the development of extrahepatic co-morbidities is under investigation. The impact of NAFLD on the development of chronic kidney disease (CKD) is incompletely understood. The aim of this study was to explore the potential contribution of NAFLD on CKD in Germany. METHODS: The Disease Analyzer Database covering 7.49 million cases in Germany was explored for patients diagnosed with NAFLD between 2000 and 2015 and was matched 1:1 to a cohort without NAFLD. Matching criteria included age, sex, physician, index year and co-diagnoses associated with CKD. The primary outcomes of thi…

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Enhanced protection of C57 BL/6 vs Balb/c mice to melanoma liver metastasis is mediated by NK cells.

ABSTRACT The B16F10 murine melanoma cell line displays a low expression of MHC class I molecules favoring immune evasion and metastases in immunocompetent C57 BL/6 wild-type mice. Here, we generated metastases to the liver, an organ that is skewed towards immune tolerance, by intrasplenic injection of B16F10 cells in syngeneic C57 BL/6 compared to allogeneic Balb/c mice. Surprisingly, Balb/c mice, which usually display a pronounced M2 macrophage and Th2 T cell polarization, were ∼3 times more susceptible to metastasis than C57 BL/6 mice, despite a much higher M1 and Th1 T cell immune response. The anti-metastatic advantage of C57 BL/6 mice could be attributed to a more potent NK-cell mediat…

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Reductive Decationizable Block Copolymers for Stimuli-Responsive mRNA Delivery

Messenger ribonucleic acids (mRNAs) are considered as promising alternatives for transient gene therapy, but to overcome their poor pharmacokinetic properties, smart carriers are required for cellular uptake and stimuli-responsive release. In this work, a synthetic concept toward reductive decationizable cationic block copolymers for mRNA complexation is introduced. By combination of RAFT block copolymerization with postpolymerization modification, cationic block copolymers are generated with disulfide-linked primary amines. They allow effective polyplex formation with negatively charged mRNA and subsequent release under reductive conditions of the cytoplasm. In first in vitro experiments w…

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P0311 : Balb/c and C57/Bl6 mice exhibit differences in their susceptibility and anti-tumor response to B16F10 melanoma liver metastasis

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Association Between Serum Levels of Neurofilament Light Chains and Minimal Hepatic Encephalopathy in Patients With Liver Cirrhosis.

INTRODUCTION: Serum biomarkers for the diagnosis of minimal hepatic encephalopathy (MHE) in patients with liver cirrhosis would be desirable. In this proof-of-concept study, we investigated the association between MHE and serum levels of neurofilament light chains (sNfL) in patients with liver cirrhosis. METHODS: sNfL were studied in patients with liver cirrhosis (with or without MHE) and controls (patients with ischemic stroke, transitory ischemic attack, and healthy individuals). MHE was diagnosed using the Psychometric Hepatic Encephalopathy Score. RESULTS: Patients with MHE showed higher sNfL than patients without MHE and controls. In multivariable analyses, higher sNfL were independent…

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Nanomedicine: In Vivo Gene-Silencing in Fibrotic Liver by siRNA-Loaded Cationic Nanohydrogel Particles (Adv. Healthcare Mater. 18/2015)

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P0419 : In vivo cell specific gene silencing in the liver using novel siRNA-loaded nanohydrogel particles

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Physicochemical and Preclinical Evaluation of Spermine-Derived Surfactant Liposomes for in Vitro and in Vivo siRNA-Delivery to Liver Macrophages

Herein we report on a liposomal system for siRNA delivery consisting of cholesterol (Chol), distearoylphosphatidylcholine (DSPC), and surfactant TF (1-hydroxy-50-amino-3,4,7,10,13,16,19,22-octaoxa-37,41,45-triaza-pentacontane), a novel spermine derivative (HO-EG8-C12-spermine) which has shown improved siRNA delivery to cells in vitro and in vivo. Predominantly single-walled liposomes with reproducible sizes and moderately broad size distributions were generated with an automated extrusion device. The liposomes remained stable when prepared in the presence of siRNA at N/P ratios of 17-34. However, when mixed with human serum in equal volumes, larger aggregates in the size range of several hu…

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Gold(I) Biscarbene Complexes Derived from Vascular-Disrupting Combretastatin A-4 Address Different Targets and Show Antimetastatic Potential

Gold N-heterocyclic carbene (NHC) complexes are an emerging class of anticancer drugs. We present a series of gold(I) biscarbene complexes with NHC ligands derived from the plant metabolite combretastatin A-4 (CA-4) that retain its vascular-disrupting effect, yet address different cellular and protein targets. Unlike CA-4, these complexes did not interfere with tubulin, but with the actin cytoskeleton of endothelial and cancer cells. For the highly metastatic 518A2 melanoma cell line this effect was accompanied by a marked accumulation of cells in the G1 phase of the cell cycle and a suppression of active prometastatic matrix metalloproteinase-2. Despite these mechanistic differences the co…

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Validation of the Clinical Frailty Scale for the Prediction of Mortality in Patients With Liver Cirrhosis

Introduction Frailty is a common but often underestimated complication in patients with liver cirrhosis. The Clinical Frailty Scale (CFS) allows the assessment of frailty within a short period of time but has only been investigated in a Canadian cohort of outpatients. The aim of the current study was to evaluate the ability of the CFS to predict mortality in outpatients and nonelectively hospitalized German patients. Methods Two hundred outpatients and 99 nonelectively hospitalized patients with liver cirrhosis were prospectively enrolled. Outpatients/inpatients were followed for a median of 364/28 days regarding the primary outcome of death or liver transplantation. Eighty-seven patients o…

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Definitive evidence for Club cells as progenitors for mutantKras/Trp53‐deficient lung cancer

Accumulating evidence suggests that both the nature of oncogenic lesions and the cell-of-origin can strongly influence cancer histopathology, tumor aggressiveness and response to therapy. Although oncogenic Kras expression and loss of Trp53 tumor suppressor gene function have been demonstrated to initiate murine lung adenocarcinomas (LUADs) in alveolar type II (AT2) cells, clear evidence that Club cells, representing the second major subset of lung epithelial cells, can also act as cells-of-origin for LUAD is lacking. Equally, the exact anatomic location of Club cells that are susceptible to Kras transformation and the resulting tumor histotype remains to be established. Here, we provide de…

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Nanoparticular bisphosphonate to selectively target and repolarize liver macrophages for efficient anti-tumour responses

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Applicability and safety of discontinuous ADVanced Organ Support (ADVOS) in the treatment of patients with acute-on-chronic liver failure (ACLF) outside of intensive care.

Background ADVanced Organ Support (ADVOS) is a novel type of extracorporeal albumin dialysis and holds promise to sustain liver function and recovery of patients with acute-on-chronic liver failure (ACLF). Previously, ADVOS was tested as continuous treatment for intensive care patients with liver failure. Data related to the applicability and safety as discontinuous treatment outside of ICU is not available. Aim Evaluation of ADVOS as discontinuous treatment for patients with ACLF outside intensive care unit and comparison with a matched historic cohort. Methods and results In this retrospective study, 26 patients with ACLF and the indication for renal replacement therapy related to HRS-AK…

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Rapamycin and Zoledronic acid exert a potent antifibrotic effect in murine biliary fibrosis

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In Vivo siRNA Delivery to Immunosuppressive Liver Macrophages by alpha-Mannosyl-Functionalized Cationic Nanohydrogel Particles

Macrophages are the front soldiers of the innate immune system and are vital for immune defense, tumor surveillance, and tissue homeostasis. In chronic diseases, including cancer and liver fibrosis, macrophages can be forced into an immunosuppressive and profibrotic M2 phenotype. M2-type macrophages overexpress the mannose receptor CD206. Targeting these cells via CD206 and macrophage repolarization towards an immune stimulating and antifibrotic M1 phenotype through RNA interference represents an appealing therapeutic approach. We designed nanohydrogel particles equipped with mannose residues on the surface (ManNP) that delivered siRNA more efficiently to M2 polarized macrophages compared t…

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In Vivo Gene-Silencing in Fibrotic Liver by siRNA-Loaded Cationic Nanohydrogel Particles

Cationic nanohydrogel particles loaded with anti-Col1α1 siRNA suppress collagen synthesis and deposition in fibrotic mice: Systemically administered 40 nm sized nanogel particles accumulate in collagen-expressing cells in the liver. Their siRNA payload induces a sequence specific in vivo gene knockdown affording an efficient antifibrotic effect in mice with liver fibrosis.

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In vivo gene silencing in the liver: Comparison of siRNA-loaded non biodegradable vs. biodegradable nanohydrogel particles for antifibrotic therapy

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Great Expectations: Principal Investigator and Trainee Perspectives on Hiring, Supervision, and Mentoring

A functioning mentor–trainee relationship is of high importance in academia. Discrepancies in expectations between principal investigators (PIs) and trainees are a source of misunderstandings and conflicts, endangering scientific progress and career advancement. In this pilot study, we sought to explore the expectations of PIs and trainees, providing consensus data from physician‐scientists and junior researchers who attended an educational workshop, entitled “The EASL/AASLD Masterclass,” in December 2017. Twenty‐three Masterclass attendees, comprising nine trainees (four Ph.D. candidates, five postdoctoral researchers) and 14 PIs, responded to an online survey. Both parties were asked to s…

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Zoledronic Acid promotes tumoricidal immunity and supresses' tumour associated macrophages and myeloid derived suppressor cells in murine HCC

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In Vivo Myofibroblast Specific Gene Silencing in the Liver Using Novel Sirna-Loaded Biodegradable Nanohydrogel Particles

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α-Mannosyl-Functionalized Cationic Nanohydrogel Particles for Targeted Gene Knockdown in Immunosuppressive Macrophages

Immunosuppressive M2 macrophages govern the immunophathogenic micromilieu in many severe diseases including cancer or fibrosis, thus, their re-polarization through RNA interference is a promising concept to support combinatorial therapies. For targeted siRNA delivery, however, safe and stable carriers are required that manage cell specific transport to M2 macrophages. Here, siRNA-loaded cationic nanogels are reported with α-mannosyl decorated surfaces that target and modify M2 macrophages selectively. Via amphiphilic precursor block copolymers bearing one single α-mannosyl moiety at their chain end mannosylated cationic nanohydrogel particles (ManNP) were obtained of 20 nm diameter determin…

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P0312 : Preclinical evaluation of dextran-based therapeutic nanoparticles for hepatic drug delivery

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Dextran-based therapeutic nanoparticles for hepatic drug delivery.

Aim: Evaluation of dextran-based nanoparticles (DNP) as a drug delivery system to target myeloid cells of the liver. Materials & methods: DNP were synthesized and optionally PEGylated. Their toxicity and cellular uptake were studied in vitro. Empty and siRNA-carrying DNP were tested in vivo with regard to biodistribution and cellular uptake. Results: In vitro, DNP were taken up by cells of the myeloid lineage without compromising their viability. In vivo, empty and siRNA-carrying DNP distributed to the liver where a single treatment addressed approximately 70% of macrophages and dendritic cells. Serum parameters indicated no in vivo toxicity. Conclusion: DNP are multifunctional liver-s…

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New 3-Aryl-2-(2-Thienyl)acrylonitriles with High Activity against Hepatoma Cells

New 2-(thien-2-yl)-acrylonitriles with putative kinase inhibitory activity were prepared and tested for their antineoplastic efficacy in hepatoma models. Four out of the 14 derivatives were shown to inhibit hepatoma cell proliferation at (sub-)micromolar concentrations with IC50 values below that of the clinically relevant multikinase inhibitor sorafenib, which served as a reference. Colony formation assays as well as primary in vivo examinations of hepatoma tumors grown on the chorioallantoic membrane of fertilized chicken eggs (CAM assay) confirmed the excellent antineoplastic efficacy of the new derivatives. Their mode of action included an induction of apoptotic capsase-3 activity, whil…

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Symptom burden and treatment response in patients with primary biliary cholangitis (PBC) – real life data form Germany

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CCDC 1500972: Experimental Crystal Structure Determination

Related Article: Julienne K. Muenzner, Bernhard Biersack, Alexander Albrecht, Tobias Rehm, Ulrike Lacher, Wolfgang Milius, Angela Casini, Jing-Jing Zhang, Ingo Ott, Viktor Brabec, Olga Stuchlikova, Ion C. Andronache, Leonard Kaps, Detlef Schuppan, Rainer Schobert|2016|Chem.-Eur.J.|22|18953|doi:10.1002/chem.201604246

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