@article{ŽutićMatosAbiagueScharfetal.2019, author = {Žutić, Igor and Matos-Abiague, Alex and Scharf, Benedikt and Dery, Hanan and Belashchenko, Kirill}, title = {Proximitized materials}, series = {Materials Today}, volume = {22}, journal = {Materials Today}, doi = {10.1016/j.mattod.2018.05.003}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-233972}, pages = {85-107}, year = {2019}, abstract = {Advances in scaling down heterostructures and having an improved interface quality together with atomically thin two-dimensional materials suggest a novel approach to systematically design materials. A given material can be transformed through proximity effects whereby it acquires properties of its neighbors, for example, becoming superconducting, magnetic, topologically nontrivial, or with an enhanced spin-orbit coupling. Such proximity effects not only complement the conventional methods of designing materials by doping or functionalization but also can overcome their various limitations. In proximitized materials, it is possible to realize properties that are not present in any constituent region of the considered heterostructure. While the focus is on magnetic and spin-orbit proximity effects with their applications in spintronics, the outlined principles also provide a broader framework for employing other proximity effects to tailor materials and realize novel phenomena.}, language = {en} } @article{McCollGrollJungstetal.2018, author = {McColl, Erin and Groll, J{\"u}rgen and Jungst, Tomasz and Dalton, Paul D.}, title = {Design and fabrication of melt electrowritten tubes using intuitive software}, series = {Materials and Design}, volume = {155}, journal = {Materials and Design}, doi = {10.1016/j.matdes.2018.05.036}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-223891}, pages = {46-58}, year = {2018}, abstract = {This study approaches the accurate continuous direct-writing onto a cylindrical collector from a mathematical perspective, taking into account the winding angle, cylinder diameter and length required for the final 3D printed tube. Using an additive manufacturing process termed melt electrowriting (MEW), porous tubes intended for tissue engineering applications are fabricated from medical-grade poly(ε-caprolactone) (PCL), validating the mathematically-derived method. For the fabricated tubes in this study, the pore size, winding angle and printed length can all be planned in advance and manufactured as designed. The physical dimensions of the tubes matched theoretical predictions and mechanical testing performed demonstrated that variations in the tubular morphology have a direct impact on their strength. MEWTubes, the web-based application developed and described here, is a particularly useful tool for planning the complex continuous direct writing path required for MEW onto a rotating, cylindrical build surface.}, language = {en} } @article{FazziniLaminaFendtetal.2019, author = {Fazzini, Federica and Lamina, Claudia and Fendt, Liane and Schultheiss, Ulla T. and Kotsis, Fruzsina and Hicks, Andrew A. and Meiselbach, Heike and Weissensteiner, Hansi and Forer, Lukas and Krane, Vera and Eckardt, Kai-Uwe and K{\"o}ttgen, Anna and Kronenberg, Florian}, title = {Mitochondrial DNA copy number is associated with mortality and infections in a large cohort of patients with chronic kidney disease}, series = {Kidney International}, volume = {96}, journal = {Kidney International}, organization = {GCKD Investigators}, doi = {10.1016/j.kint.2019.04.021}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-227662}, pages = {480-488}, year = {2019}, abstract = {Damage of mitochondrial DNA (mtDNA) with reduction in copy number has been proposed as a biomarker for mitochondrial dysfunction and oxidative stress. Chronic kidney disease (CKD) is associated with increased mortality and risk of cardiovascular disease, but the underlying mechanisms remain incompletely understood. Here we investigated the prognostic role of mtDNA copy number for cause-specific mortality in 4812 patients from the German Chronic Kidney Disease study, an ongoing prospective observational national cohort study of patients with CKD stage G3 and A1-3 or G1-2 with overt proteinuria (A3) at enrollment. MtDNA was quantified in whole blood using a plasmid-normalized PCR-based assay. At baseline, 1235 patients had prevalent cardiovascular disease. These patients had a significantly lower mtDNA copy number than patients without cardiovascular disease (fully-adjusted model: odds ratio 1.03, 95\% confidence interval [CI] 1.01-1.05 per 10 mtDNA copies decrease). After four years of follow-up, we observed a significant inverse association between mtDNA copy number and all-cause mortality, adjusted for kidney function and cardiovascular disease risk factors (hazard ratio 1.37, 95\% CI 1.09-1.73 for quartile 1 compared to quartiles 2-4). When grouped by causes of death, estimates pointed in the same direction for all causes but in a fully-adjusted model decreased copy numbers were significantly lower only in infection-related death (hazard ratio 1.82, 95\% CI 1.08-3.08). A similar association was observed for hospitalizations due to infections in 644 patients (hazard ratio 1.19, 95\% CI 1.00-1.42 in the fully-adjusted model). Thus, our data support a role of mitochondrial dysfunction in increased cardiovascular disease and mortality risks as well as susceptibility to infections in patients with CKD.}, language = {en} } @article{ZhangYeGburecketal.2018, author = {Zhang, Zishuai and Ye, Siyu and Gbureck, Uwe and Barralet, Jake E. and Merle, G{\´e}raldine}, title = {Cavitation Mediated 3D Microstructured Architectures from Nanocarbon}, series = {Advanced Functional Materials}, volume = {28}, journal = {Advanced Functional Materials}, doi = {10.1002/adfm.201706832}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-233926}, year = {2018}, abstract = {Here, the formation of high surface area microscale assemblies of nanocarbon through phosphate and ultrasound cavitation treatment is reported. Despite high conductivity and large surface area, potential health and safety concerns limit the use of nanocarbon and add challenges to handling. Previously, it is shown that phosphate ultrasonic bonding is ineffective for organic materials but in this study, it is found that by a preliminary oxidizing treatment, several carbons can be readily assembled from xerogels. Assembling nanocarbon into microparticles can usually require a binder or surfactants, which can reduce surface area or conductivity and generate a low microsphere yield. Carbon nanotube microspheres are nitrogen-doped and flower-like nanostructured Pt deposited on their surface, and finally showcased as efficient cathode electrocatalysts for the oxygen reduction reaction (half-wave potential 0.78 V vs reversible hydrogen electrode) and methanol oxidation (417 mA mg-1). In particular, no significant degradation of the catalysts is detected after 12 000 cycles (26.6 h). These results indicate the potential of this multimaterial assembly method and open a new way to improve handling of nanoscale materials.}, language = {en} } @article{McMasterHoefnerHrynevichetal.2019, author = {McMaster, Rebecca and Hoefner, Christiane and Hrynevich, Andrei and Blum, Carina and Wiesner, Miriam and Wittmann, Katharina and Dargaville, Tim R. and Bauer-Kreisel, Petra and Groll, J{\"u}rgen and Dalton, Paul D. and Blunk, Torsten}, title = {Tailored Melt Electrowritten Scaffolds for the Generation of Sheet-Like Tissue Constructs from Multicellular Spheroids}, series = {Advanced Healthcare Materials}, volume = {8}, journal = {Advanced Healthcare Materials}, doi = {10.1002/adhm.201801326}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-223921}, year = {2019}, abstract = {Melt electrowriting (MEW) is an additive manufacturing technology that is recently used to fabricate voluminous scaffolds for biomedical applications. In this study, MEW is adapted for the seeding of multicellular spheroids, which permits the easy handling as a single sheet-like tissue-scaffold construct. Spheroids are made from adipose-derived stromal cells (ASCs). Poly(ε-caprolactone) is processed via MEW into scaffolds with box-structured pores, readily tailorable to spheroid size, using 13-15 µm diameter fibers. Two 7-8 µm diameter "catching fibers" near the bottom of the scaffold are threaded through each pore (360 and 380 µm) to prevent loss of spheroids during seeding. Cell viability remains high during the two week culture period, while the differentiation of ASCs into the adipogenic lineage is induced. Subsequent sectioning and staining of the spheroid-scaffold construct can be readily performed and accumulated lipid droplets are observed, while upregulation of molecular markers associated with successful differentiation is demonstrated. Tailoring MEW scaffolds with pores allows the simultaneous seeding of high numbers of spheroids at a time into a construct that can be handled in culture and may be readily transferred to other sites for use as implants or tissue models.}, language = {en} } @article{SelcukTokluBeykanetal.2018, author = {Selcuk, Nalan Alan and Toklu, Turkay and Beykan, Seval and Karaaslan, Serife Ipek}, title = {Evaluation of the dosimetry approaches in ablation treatment of thyroid cancer}, series = {Journal of Applied Clinical Medical Physics}, volume = {19}, journal = {Journal of Applied Clinical Medical Physics}, doi = {10.1002/acm2.12350}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-235882}, pages = {134-140}, year = {2018}, abstract = {In this study, we aimed to evaluate dosimetric approaches in ablation treatment of Differentiated Thyroid Carcinoma (DTC) without interrupting the clinical routine. Prior to therapy, 10.7 MBq 131I in average was orally given to 24 patients suffering from DTC. MIRD formalism was used for dosimetric calculations. For blood and bone marrow dosimetry, blood samples and whole-body counts were collected at 2, 24, 72, and 120 h after I-131 administration. For remnant tissue dosimetry, uptake measurements were performed at the same time intervals. To estimate the remnant volume, anterior and lateral planar gamma camera images were acquired with a reference source within the field of view at 24 h after I-131 administration. Ultrasound imaging was also performed. Treatment activities determined with the fixed activity method were administered to the patients. Secondary cancer risk relative to applied therapy was evaluated for dosimetric approaches. The average dose to blood and bone marrow were determined as 0.15 ± 0.04 and 0.11 ± 0.04 Gy/GBq, respectively. The average remnant tissue dose was 0.58 ± 0.52 Gy/MBq and the corresponding required activity to ablate the remnant was approximately 1.3 GBq of 131I. A strong correlation between 24th-hour uptake and time-integrated activity coefficient values was obtained. Compared to fixed activity method, approximately five times higher secondary cancer risk was determined in bone marrow dosimetry, while the risk was about three times lower in lesion-based dosimetry.}, language = {en} } @article{GoettlichKunzZappetal.2018, author = {G{\"o}ttlich, Claudia and Kunz, Meik and Zapp, Cornelia and Nietzer, Sarah L. and Walles, Heike and Dandekar, Thomas and Dandekar, Gudrun}, title = {A combined tissue-engineered/in silico signature tool patient stratification in lung cancer}, series = {Molecular Oncology}, volume = {12}, journal = {Molecular Oncology}, doi = {10.1002/1878-0261.12323}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-233137}, pages = {1264-1285}, year = {2018}, abstract = {Patient-tailored therapy based on tumor drivers is promising for lung cancer treatment. For this, we combined in vitro tissue models with in silico analyses. Using individual cell lines with specific mutations, we demonstrate a generic and rapid stratification pipeline for targeted tumor therapy. We improve in vitro models of tissue conditions by a biological matrix-based three-dimensional (3D) tissue culture that allows in vitro drug testing: It correctly shows a strong drug response upon gefitinib (Gef) treatment in a cell line harboring an EGFR-activating mutation (HCC827), but no clear drug response upon treatment with the HSP90 inhibitor 17AAG in two cell lines with KRAS mutations (H441, A549). In contrast, 2D testing implies wrongly KRAS as a biomarker for HSP90 inhibitor treatment, although this fails in clinical studies. Signaling analysis by phospho-arrays showed similar effects of EGFR inhibition by Gef in HCC827 cells, under both 2D and 3D conditions. Western blot analysis confirmed that for 3D conditions, HSP90 inhibitor treatment implies different p53 regulation and decreased MET inhibition in HCC827 and H441 cells. Using in vitro data (western, phospho-kinase array, proliferation, and apoptosis), we generated cell line-specific in silico topologies and condition-specific (2D, 3D) simulations of signaling correctly mirroring in vitro treatment responses. Networks predict drug targets considering key interactions and individual cell line mutations using the Human Protein Reference Database and the COSMIC database. A signature of potential biomarkers and matching drugs improve stratification and treatment in KRAS-mutated tumors. In silico screening and dynamic simulation of drug actions resulted in individual therapeutic suggestions, that is, targeting HIF1A in H441 and LKB1 in A549 cells. In conclusion, our in vitro tumor tissue model combined with an in silico tool improves drug effect prediction and patient stratification. Our tool is used in our comprehensive cancer center and is made now publicly available for targeted therapy decisions.}, language = {en} } @article{StromeckiTatariCoudiereMorrisonetal.2018, author = {Stromecki, Margaret and Tatari, Nazanin and Coudi{\`e}re Morrison, Ludivine and Kaur, Ravinder and Zagozewski, Jamie and Palidwor, Gareth and Ramaswamy, Vijay and Skowron, Patryk and W{\"o}lfl, Matthias and Milde, Till and Del Bigio, Marc R. and Taylor, Michael D. and Werbowetski-Ogilvie, Tamra E.}, title = {Characterization of a novel OTX2-driven stem cell program in Group 3 and Group 4 medulloblastoma}, series = {Molecular Oncology}, volume = {12}, journal = {Molecular Oncology}, doi = {10.1002/1878-0261.12177}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-240089}, pages = {495-513}, year = {2018}, abstract = {Medulloblastoma (MB) is the most common malignant primary pediatric brain cancer. Among the most aggressive subtypes, Group 3 and Group 4 originate from stem/progenitor cells, frequently metastasize, and often display the worst prognosis, yet we know the least about the molecular mechanisms driving their progression. Here, we show that the transcription factor orthodenticle homeobox 2 (OTX2) promotes self-renewal while inhibiting differentiation in vitro and increases tumor initiation from MB stem/progenitor cells in vivo. To determine how OTX2 contributes to these processes, we employed complementary bioinformatic approaches to characterize the OTX2 regulatory network and identified novel relationships between OTX2 and genes associated with neuronal differentiation and axon guidance signaling in Group 3 and Group 4 MB stem/progenitor cells. In particular, OTX2 levels were negatively correlated with semaphorin (SEMA) signaling, as expression of 9 SEMA pathway genes is upregulated following OTX2 knockdown with some being potential direct OTX2 targets. Importantly, this negative correlation was also observed in patient samples, with lower expression of SEMA4D associated with poor outcome specifically in Group 4 tumors. Functional proof-of-principle studies demonstrated that increased levels of select SEMA pathway genes are associated with decreased self-renewal and growth in vitro and in vivo and that RHO signaling, known to mediate the effects of SEMA genes, is contributing to the OTX2 KD phenotype. Our study provides mechanistic insight into the networks controlled by OTX2 in MB stem/progenitor cells and reveals novel roles for axon guidance genes and their downstream effectors as putative tumor suppressors in MB.}, language = {en} } @article{StoreyStaplinHaynesetal.2018, author = {Storey, Benjamin C. and Staplin, Natalie and Haynes, Richard and Reith, Christina and Emberson, Jonathan and Herrington, William G. and Wheeler, David C. and Walker, Robert and Fellstr{\"o}m, Bengt and Wanner, Christoph and Landray, Martin J. and Baigent, Colin}, title = {Lowering LDL cholesterol reduces cardiovascular risk independently of presence of inflammation}, series = {Kidney International}, volume = {93}, journal = {Kidney International}, organization = {The SHARP Collaborative Group}, doi = {10.1016/j.kint.2017.09.011}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-240067}, pages = {1000-1007}, year = {2018}, abstract = {Markers of inflammation, including plasma C-reactive protein (CRP), are associated with an increased risk of cardiovascular disease, and it has been suggested that this association is causal. However, the relationship between inflammation and cardiovascular disease has not been extensively studied in patients with chronic kidney disease. To evaluate this, we used data from the Study of Heart and Renal Protection (SHARP) to assess associations between circulating CRP and LDL cholesterol levels and the risk of vascular and non-vascular outcomes. Major vascular events were defined as nonfatal myocardial infarction, cardiac death, stroke or arterial revascularization, with an expanded outcome of vascular events of any type. Higher baseline CRP was associated with an increased risk of major vascular events (hazard ratio per 3x increase 1.28; 95\% confidence interval 1.19-1.38). Higher baseline LDL cholesterol was also associated with an increased risk of major vascular events (hazard ratio per 0.6 mmol/L higher LDL cholesterol; 1.14, 1.06-1.22). Higher baseline CRP was associated with an increased risk of a range of non-vascular events (1.16, 1.12-1.21), but there was a weak inverse association between baseline LDL cholesterol and non-vascular events (0.96, 0.92-0.99). The efficacy of lowering LDL cholesterol with simvastatin/ezetimibe on major vascular events, in the randomized comparison, was similar irrespective of CRP concentration at baseline. Thus, decisions to offer statin-based therapy to patients with chronic kidney disease should continue to be guided by their absolute risk of atherosclerotic events. Estimation of such risk may include plasma biomarkers of inflammation, but there is no evidence that the relative beneficial effects of reducing LDL cholesterol depends on plasma CRP concentration.}, language = {en} } @article{HoeniglOraschFaserletal.2019, author = {Hoenigl, Martin and Orasch, Thomas and Faserl, Klaus and Prattes, Juergen and Loeffler, Juergen and Springer, Jan and Gsaller, Fabio and Reischies, Frederike and Duettmann, Wiebke and Raggam, Reinhard B. and Lindner, Herbert and Haas, Hubertus}, title = {Triacetylfusarinine C: A urine biomarker for diagnosis of invasive aspergillosis}, series = {Journal of Infection}, volume = {78}, journal = {Journal of Infection}, doi = {10.1016/j.jinf.2018.09.006}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-320939}, pages = {150-157}, year = {2019}, abstract = {Objectives Early diagnosis of invasive aspergillosis (IA) remains challenging, with available diagnostics being limited by inadequate sensitivities and specificities. Triacetylfusarinine C, a fungal siderophore that has been shown to accumulate in urine in animal models, is a potential new biomarker for diagnosis of IA. Methods We developed a method allowing absolute and matrix-independent mass spectrometric quantification of TAFC. Urine TAFC, normalized to creatinine, was determined in 44 samples from 24 patients with underlying hematologic malignancies and probable, possible or no IA according to current EORTC/MSG criteria and compared to other established biomarkers measured in urine and same-day blood samples. Results TAFC/creatinine sensitivity, specificity, positive and negative likelihood ratio for probable versus no IA (cut-off ≥ 3) were 0.86, 0.88, 6.86, 0.16 per patient. Conclusion For the first time, we provide proof for the occurrence of TAFC in human urine. TAFC/creatinine index determination in urine showed promising results for diagnosis of IA offering the advantages of non-invasive sampling. Sensitivity and specificity were similar as reported for GM determination in serum and bronchoalveolar lavage, the gold standard mycological criterion for IA diagnosis.}, language = {en} }