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3-hydroxy-3-methylglutaryl-coenzyme A lyase deficiency: one disease - many faces (2020)

Grünert, Sarah C. ; Sass, Jörn Oliver

Background: 3-hydroxy-3-methylglutaryl-coenzyme A lyase deficiency (HMGCLD) is an autosomal recessive disorder of ketogenesis and leucine degradation due to mutations in HMGCL. Method: We performed a systematic literature search to identify all published cases. Two hundred eleven patients of whom relevant clinical data were available were included in this analysis. Clinical course, biochemical findings and mutation data are highlighted and discussed. An overview on all published HMGCL variants is provided. Results: More than 95% of patients presented with acute metabolic decompensation. Most patients manifested within the first year of life, 42.4% already neonatally. Very few individuals remained asymptomatic. The neurologic long-term outcome was favorable with 62.6% of patients showing normal development. Conclusion: This comprehensive data analysis provides a systematic overview on all published cases with HMGCLD including a list of all known HMGCL mutations.

Thermal expansion of semi-crystalline polymers: Anisotropic thermal strain and crystallite orientation (2020)

Ramakers-van Dorp, Esther ; Möginger, Bernhard ; Hausnerova, Berenika

Analytische Chemie I (2020)

Ritgen, Ulf

Processed-Induced Thermal and Viscoelastic Behavior of Extrusion Blow Molded Parts (2019)

Ramakers-van Dorp, Esther

Process-dependent thermo-mechanical viscoelastic properties and the corresponding morphology of HDPE extrusion blow molded (EBM) parts were investigated. Evaluation of bulk data showed that flow direction, draw ratio, and mold temperature influence the viscoelastic behavior significantly in certain temperature ranges. Flow induced orientations due to higher draw ratio and higher mold temperature lead to higher crystallinities. To determine the local viscoelastic properties, a new microindentation system was developed by merging indentation with dynamic mechanical analysis. The local process-structure-property relationship of EBM parts showed that the cross-sectional temperature distribution is clearly reflected by local crystallinities and local complex moduli. Additionally, a model to calculate three-dimensional anisotropic coefficients of thermal expansion as a function of the process dependent crystallinity was developed based on an elementary volume unit cell with stacked layers of amorphous phase and crystalline lamellae. Good agreement of the predicted thermal expansion coefficients with measured ones was found up to a temperature of 70 °C.

Influence of organic additives on the synthesis of calcium silicate hydrates (C-S-H) based on the pozzolanic reaction (2019)

Geppert, Alexander

Isolation and characterization of therapeutic active exosomes for an anti-inflammatory exosomes based therapy of immunudisfuction disease as rheumatiodarth (2015)

Amin, Shadi

Synthesis and biological evaluation of nitrile-based peptiomimetic inhibitors fore cysteine cathepsins (2016)

Schmitz, Janina

Acceleration of Portland cement with lithium, sodium and potassium silicates and hydroxides (2020)

Witzleben, Steffen Thomas

2-methylacetoacetyl-coenzyme A thiolase (beta-ketothiolase) deficiency: one disease - two pathways (2019)

Grünert, Sarah Catharina ; Sass, Jörn Oliver

Background: 2-methylacetoacetyl-coenzyme A thiolase deficiency (MATD; deficiency of mitochondrial acetoacetyl-coenzyme A thiolase T2/ “beta-ketothiolase”) is an autosomal recessive disorder of ketone body utilization and isoleucine degradation due to mutations in ACAT1. Methods: We performed a systematic literature search for all available clinical descriptions of patients with MATD. 244 patients were identified and included in this analysis. Clinical course and biochemical data are presented and discussed. Results: For 89.6 % of patients at least one acute metabolic decompensation was reported. Age at first symptoms ranged from 2 days to 8 years (median 12 months). More than 82% of patients presented in the first two years of life, while manifestation in the neonatal period was the exception (3.4%). 77.0% (157 of 204 patients) of patients showed normal psychomotor development without neurologic abnormalities. Conclusion: This comprehensive data analysis provides a systematic overview on all cases with MATD identified in the literature. It demonstrates that MATD is a rather benign disorder with often favourable outcome, when compared with many other organic acidurias.

3-hydroxy-3-methylglutaryl-coenzyme A lyase deficiency: One disease- many faces (2019)

Grünert, Sarah Catharina ; Sass, Jörn Oliver

Background 3-hydroxy-3-methylglutaryl-coenzyme A lyase deficiency (HMGCLD) is an autosomal recessive disorder of ketogenesis and leucine degradation due to mutations in HMGCL . Method We performed a systematic literature search to identify all published cases. 211 patients of whom relevant clinical data were available were included in this analysis. Clinical course, biochemical findings and mutation data are highlighted and discussed. An overview on all published HMGCL variants is provided. Results More than 95% of patients presented with acute metabolic decompensation. Most patients manifested within the first year of life, 42.4% already neonatally. Very few individuals remained asymptomatic. The neurologic long-term outcome was favorable with 62.6% of patients showing normal development. Conclusion This comprehensive data analysis provides a systematic overview on all published cases with HMGCLD including a list of all known HMGCL mutations.

A Study on the Pozzolanic Properties of Pennisetum Purpureum Ash (2018)

Saruchera, L. ; Mupa, Mathew ; Muchanyereyi-Mukuratirwa, N. ; Witzleben, Steffen

Pozzolanic properties of Pennisetum purpureum grass ash were tested on Portland cement. Results show that the ash can be blended with cements without compromising binding strength of the cement. It was found that Portland cement could be blended with Pennisetum purpureum up to a ratio of 3:2 compromising compressive strength of mortar.Mortar with lower cement replacement took longer to set as evidenced by lower compressive strength within the 28-day aging time. Mortar with higher cement replacement had lower water absorption capacity, an indication that the test pozzolan was of smaller particulate size. XRF analysis and the FTIR spectrum showed that the ash has a higher content of silica. The XRD pattern of the ash showed that the ash was predominantly amorphous. SEM images showed that the ash produced at 600 o C had residual carbon material.

Mesenchymal Stem Cells (2020)

Tonk, Christian Horst ; Witzler, Markus ; Schulze, Margit ; Tobiasch, Edda

This chapter focuses on mesenchymal stem cells (MSCs), a multipotent stem cell type that has been found in a variety of tissues and organs of the human body since their discovery in 1970. Their main function is to maintain and repair the respective tissue in vivo. Mesenchymal stem cells can be easily isolated from different tissues and can undergo extensive self-proliferation prior to differentiation into various mesodermal cell types such as osteoblasts, chondrocytes, adipocytes, tenocytes, myocytes, and fibroblasts. Because of this vast differentiation potential, mesenchymal stem cells are a promising tool for regenerative medicine approaches. They could play an important role in cellular therapy, tissue replacement and regeneration in the future. Mesenchymal stem cells will be compared for their application and differentiation potential to embryonic stem cells and induced pluripotent stem cells and the limitations and challenges using scaffolds for tissue repair will be presented. In addition, legal and ethical aspects of the use of mesenchymal stem cells will be discussed. Moreover, isolation protocols for mesenchymal stem cells from the most common sources namely bone marrow, adipose tissue and umbilical cord are included.

Local process-dependent structural and mechanical properties of extrusion blow molded high-density polyethylene hollow parts (2020)

Ramakers-van Dorp, Esther ; Eger, Benedikt ; Raschen, Clemens ; Urbanek, Michal ; Möginger, Bernhard ; Hausnerova, Berenika

d-Glycerate kinase deficiency in a neuropediatric patient (2020)

Sass, Jörn Oliver ; Behringer, Sidney ; Fernando, Malkanthi ; Cesaroni, Elisabetta ; Cursio, Ida ; Volpini, Alberto ; Till, Claudia

Chromenones as Multineurotargeting Inhibitors of Human Enzymes (2019)

Lemke, Carina ; Christmann, Joscha ; Yin, Jiafei ; Alonso, José M. ; Serrano, Estefanía ; Chioua, Mourad ; Ismaili, Lhassane ; Martínez-Grau, María Angeles ; Beadle, Christopher D. ; Vetman, Tatiana ; Dato, Florian M. ; Bartz, Ulrike ; Elsinghorst, Paul W. ; Pietsch, Markus ; Müller, Christa E. ; Iriepa, Isabel ; Wille, Timo ; Marco-Contelles, José ; Gütschow, Michael

The complex nature of multifactorial diseases, such as Morbus Alzheimer, has produced a strong need to design multitarget-directed ligands to address the involved complementary pathways. We performed a purposive structural modification of a tetratarget small-molecule, that is contilisant, and generated a combinatorial library of 28 substituted chromen-4-ones. The compounds comprise a basic moiety which is linker-connected to the 6-position of the heterocyclic chromenone core. The syntheses were accomplished by Mitsunobu- or Williamson-type ether formations. The resulting library members were evaluated at a panel of seven human enzymes, all of which being involved in the pathophysiology of neurodegeneration. A concomitant inhibition of human acetylcholinesterase and human monoamine oxidase B, with IC50 values of 5.58 and 7.20 μM, respectively, was achieved with the dual-target 6-(4-(piperidin-1-yl)butoxy)-4H-chromen-4-one (7).

Polysaccharide-Based Systems for Targeted Stem Cell Differentiation and Bone Regeneration (2019)

Witzler, Markus ; Büchner, Dominik ; Shoushrah, Sarah Hani ; Babczyk, Patrick ; Baranova, Juliana ; Witzleben, Steffen ; Tobiasch, Edda ; Schulze, Margit

Bone tissue engineering is an ever-changing, rapidly evolving, and highly interdisciplinary field of study, where scientists try to mimic natural bone structure as closely as possible in order to facilitate bone healing. New insights from cell biology, specifically from mesenchymal stem cell differentiation and signaling, lead to new approaches in bone regeneration. Novel scaffold and drug release materials based on polysaccharides gain increasing attention due to their wide availability and good biocompatibility to be used as hydrogels and/or hybrid components for drug release and tissue engineering. This article reviews the current state of the art, recent developments, and future perspectives in polysaccharide-based systems used for bone regeneration.

Multiresolution Analysis Pansharpening for the Fusion of Raman and Conventional Brightfield Microscopy Images (2019)

Pomrehn, Christoph ; Klein, Daniel ; Kolb, Andreas ; Kaul, Peter ; Herpers, Rainer

Synthesis of Substituted Hydroxyapatite for Application in Bone Tissue Engineering and Drug Delivery (2019)

Büchner, D. ; Gericke, M. ; Heinze, T. ; Tobiasch, E. ; Witzleben, S. ; Schulze, M.

Gas Chromatography (2019)

Gas chromatography (GC) is one of the most important types of chromatography used in analytical chemistry for separating and analyzing chemical organic compounds. Today, gas chromatography is one of the most widespread investigation methods of instrumental analysis. This technique is used in the laboratories of chemical, petrochemical, and pharmaceutical industries, in research institutes, and also in clinical, environmental, and food and beverage analysis. This book is the outcome of contributions by experts in the field of gas chromatography and includes a short history of gas chromatography, an overview of derivatization methods and sample preparation techniques, a comprehensive study on pyrazole mass spectrometric fragmentation, and a GC/MS/MS method for the determination and quantification of pesticide residues in grape samples.

Evaluation of STR profiles of single telogen hairs using probabilistic methods (2019)

Heß, Sarah Aurora ; Biermann, Jan-Philip ; Grabmüller, Melanie ; Madea, Burkhard ; Thiele, Ralf ; Jäger, Richard

Development and Evaluation of a Prototype Scratch Apparatus for Wound Assays Adjustable to Different Forces and Substrates (2019)

Grimmig, Roman ; Babczyk, Patrick ; Gillemot, Philipp ; Schmitz, Klaus-Peter ; Schulze, Margit ; Tobiasch, Edda

Scratch assays enable the study of the migration process of an injured adherent cell layer in vitro. An apparatus for the reproducible performance of scratch assays and cell harvesting has been developed that meets the requirements for reproducibility in tests as well as easy handling. The entirely autoclavable setup is divided into a sample translation and a scratching system. The translational system is compatible with standard culture dishes and can be modified to adapt to different cell culture systems, while the scratching system can be adjusted according to angle, normal force, shape, and material to adapt to specific questions and demanding substrates. As a result, a fully functional prototype can be presented. This system enables the creation of reproducible and clear scratch edges with a low scratch border roughness within a monolayer of cells. Moreover, the apparatus allows the collection of the migrated cells after scratching for further molecular biological investigations without the need for a second processing step. For comparison, the mechanical properties of manually performed scratch assays are evaluated.

Solar-mediated degradation of linezolid and tedizolid under simulated environmental conditions: Kinetics, transformation and toxicity (2020)

Timm, Alexander ; Abendschön, Patrick ; Tölgyesi, László ; Horn, Harald ; Borowska, Ewa

Neuartige Geopolymer-gebundene Dämmstoffe aus nachwachsenden Rohstoffen (2019)

Walbrück, Katharina ; Witzleben, Steffen ; Stephan, Dietmar

Die Nachfrage nach nachhaltigen und ökologischen Bau- und Dämmstoffen wächst, besonders im Hinblick auf den fortschreitenden Klimawandel und die knapper werdenden fossilen Ressourcen. Eine mögliche Alternative zu traditionellen Baustoffen stellen dabei nachwachsende Rohstoffe dar, denn diese sind im Vergleich zu fossilen Ressourcen CO2-neutral. [1,2]

Entwicklung und Optimierung einer Methode zur Bestimmung der antioxidativen Aktivität von Kraft- und Organosolv-Lignin via Folin- Ciocalteu-Assay (2019)

Rumpf, Jessica

Entwicklung und Optimierung einer Methode zur Bestimmung der antioxidativen Aktivität von Kraft- und Organosolv-Lignin via Folin- Ciocalteu-Assay

Untersuchungen zur Eignung von Kraft Lignin für die Herstellung von Polyurethan Filmen (2019)

Rumpf, Jessica

Untersuchungen zur Eignung von Kraft Lignin für die Herstellung von Polyurethan Filmen

FOXP3 Inhibitory Peptide P60 Increases Efficacy of Cytokine-induced Killer Cells Against Renal and Pancreatic Cancer Cells (2019)

Setiawan, Maria Fitria ; Rudan, Oliver ; Vogt, Annabelle ; Gonzalez-Carmona, Maria A. ; Langhans, Bettina ; Schmidt-Wolf, Roland ; Garofano, Francesca ; Strassburg, Christian P. ; Lasarte, Juan J. ; Casares, Noelia ; Lozano, Teresa ; Weiher, Hans ; Schmidt-Wolf, Ingo G. H.

Adaption of Energy Deposition in Helical Drilling of Multidimensional Micro Holes Using Ultrashort Laser Pulses (2019)

He, Chao ; Esch, Dominik ; Gillner, Arnold

High-precision, multidimensional holes are required in many technical applications. Due to its undercut shape, these kind of holes are usually manufactured from two sides of the work piece including a time-consuming co-axial alignment. Compared to current state of the art, a one-sided drilling strategy has numerous advantages regarding flexibility, precision and process efficiency. In this work, a helical drilling optic and an ultrashort pulse laser are utilized to fabricate a rotationally symmetric multidimensional-shaped hole in one single process step. The influences of single pulse energy, pulse repetition rate, rotation speed of laser beam as well as the drilling time on ablation depth are investigated. By varying the pulse energy and pulse density, the deposited energy per unit length on the single helical path can be adapted and thus the ablation depth can be scaled. With the adapted laser energy deposition, a T-shaped hole with a uniformed depth of about 80 mu m inlet is fabricated. Morphological analysis on the hole wall show excellent drilling quality without recast layers or heat-affected zones and roughness Rq < 0.35 mu m.

Mikrodesinfektionssystem mit strukturierten Membran-Elektroden-Arrays : Schlussbericht zum Forschungsvorhaben Ozon-Array : Förderzeitraum: 01. Juli 2016-31. Dezember 2018 (2019)

Schulze, Dirk ; Stucki, Samuel ; van Dyk, Katharina ; Witzleben, Steffen ; Oligschleger, Christina ; Grimmig, Roman

OzonArray - Entwicklung eines Elektrolyseurs mit strukturierten Membran-Elektroden-Arrays für die in situ Produktion von Ozonlösungen in Wasser beliebiger Qualität; Teilprojekt: Analyse der Stoffflüsse in strukturierten Membrane-Elektroden Arrays : Abschlussbericht (2019)

Grimmig, Roman ; Witzleben, Steffen ; Oligschleger, Christa

System accuracy assessments with a blood glucose meter with combined glucose and ß-hydroxybutyrate measurement capabilities (2019)

Weissenbacher, Sylvia ; Yang, Chen-Yu ; Kuan, Tang-Chin ; Demircik, Filiz ; Hanna, Mina ; Pfützner, Andreas

Seaweed polysaccharide based materials: From chemical derivatization to functional composite hydrogels and advanced applications (2019)

Gericke, Martin ; Witzler, Markus ; Büchner, Dominik ; Enkelmann, Astrid ; Ottensmeyer, Patrick ; Schneider, Gerlind ; Tobiasch, Edda ; Schulze, Margit ; Heinze, Thomas

Feldemissions-Elektronenmiskroskop mit Computertomographie-System für Materialentwicklungen und Sicherheitstechnologien FE-SEM-[my]CT : Schlussbericht zu FH Invest-Projekt (2019)

Witzleben, Steffen

Ingenieurnachwuchs 2013: AktivPuzzolan - Synergetische Aktivierung von synthetischen Puzzolanen mittels Templaten und Aktivatoren zur Verringerung des Portlandzementklinkergehaltes und der CO2-Emissionen bei Zementen und zementbasierten Formulierungen : Abschlussbericht zum Projekt : Förderzeitraum: 1.10.2013-30.12.2017 (2017)

Millimeter-Wellen Radar-basierter Kofferscanner bei 80 GHz als Experimentalsystem zum Einsatz bei VESPER Plus : Endbericht 07/2014 ; Unterauftrag der Hochschule Bonn-Rhein-Sieg vom 01.06.2012 (2014)

Kaul, Peter

Antimicrobial Activity of Lignin-Derived Polyurethane Coatings Prepared from Unmodified and Demethylated Lignins (2019)

Klein, Stephanie Elisabeth ; Alzagameem, Abla ; Rumpf, Jessica ; Korte, Imke ; Kreyenschmidt, Judith ; Schulze, Margit

Due to global ecological and economic challenges that have been correlated to the transition from fossil-based to renewable resources, fundamental studies are being performed worldwide to replace fossil fuel raw materials in plastic production. One aspect of current research is the development of lignin-derived polyols to substitute expensive fossil-based polyol components for polyurethane and polyester production. This article describes the synthesis of bioactive lignin-based polyurethane coatings using unmodified and demethylated Kraft lignins. Demethylation was performed to enhance the reaction selectivity toward polyurethane formation. The antimicrobial activity was tested according to a slightly modified standard test (JIS Z 2801:2010). Besides effects caused by the lignins themselves, triphenylmethane derivatives (brilliant green and crystal violet) were used as additional antimicrobial substances. Results showed increased antimicrobial capacity against Staphylococcus aureus. Furthermore, the coating color could be varied from dark brown to green and blue, respectively.

Acylpeptide hydrolase (APEH) sequence variants with potential impact on the metabolism of the antiepileptic drug valproic acid (2019)

Tsortouktzidis, Despina ; Grundke, Kathleen ; Till, Claudia ; Korwitz-Reichelt, Anne ; Sass, Jörn Oliver

Intact Transition Epitope Mapping - Targeted High-Energy Rupture of Extracted Epitopes (ITEM-THREE) (2019)

Danquah, Bright D. ; Röwer, Claudia ; Opuni, Kwabena F. M. ; El-Kased, Reham ; Frommholz, David ; Illges, Harald ; Koy, Cornelia ; Glocker, Michael O.

Epitope mapping, which is the identification of antigenic determinants, is essential for the design of novel antibody-based therapeutics and diagnostic tools. ITEM-THREE is a mass spectrometry-based epitope mapping method that can identify epitopes on antigens upon generating an immune complex in electrospray-compatible solutions by adding an antibody of interest to a mixture of peptides from which at least one holds the antibody's epitope. This mixture is nano-electrosprayed without purification. Identification of the epitope peptide is performed within a mass spectrometer that provides an ion mobility cell sandwiched in-between two collision cells and where this ion manipulation setup is flanked by a quadrupole mass analyzer on one side and a time-of-flight mass analyzer on the other side. In a stepwise fashion, immune-complex ions are separated from unbound peptide ions and dissociated to release epitope peptide ions. Immune complex-released peptide ions are separated from antibody ions and fragmented by collision induced dissociation. Epitope-containing peptide fragment ions are recorded, and mass lists are submitted to unsupervised data base search thereby retrieving both, the amino acid sequence of the epitope peptide and the originating antigen. ITEM-THREE was developed with antiTRIM21 and antiRA33 antibodies for which the epitopes were known, subjecting them to mixtures of synthetic peptides of which one contained the respective epitope. ITEM-THREE was then successfully tested with an enzymatic digest of His-tagged recombinant human β-actin and an antiHis-tag antibody, as well as with an enzymatic digest of recombinant human TNFα and an antiTNFα antibody whose epitope was previously unknown.

Investigations into the influence of chemical activators and templates on cement hydration (2019)

Witzleben, Steffen

The strength of hydrated cement and its cohesive properties are determined to a great extent by the structure of the calcium silicate hydrate phases. There is a description of investigations into the crystallization of calcium silicate hydrate (tobermorite) in the presence of various amino acids that lead to significant changes in the elementary cells.

Non-Cytotoxic Agarose/Hydroxyapatite Composite Scaffolds for Drug Release (2019)

Witzler, Markus ; Ottensmeyer, Patrick Frank ; Gericke, Martin ; Heinze, Thomas ; Tobiasch, Edda ; Schulze, Margit

Healing of large bone defects requires implants or scaffolds that provide structural guidance for cell growth, differentiation, and vascularization. In the present work, an agarose-hydroxyapatite composite scaffold was developed that acts not only as a 3D matrix, but also as a release system. Hydroxyapatite (HA) was incorporated into the agarose gels in situ in various ratios by a simple procedure consisting of precipitation, cooling, washing, and drying. The resulting gels were characterized regarding composition, porosity, mechanical properties, and biocompatibility. A pure phase of carbonated HA was identified in the scaffolds, which had pore sizes of up to several hundred micrometers. Mechanical testing revealed elastic moduli of up to 2.8 MPa for lyophilized composites. MTT testing on Lw35human mesenchymal stem cells (hMSCs) and osteosarcoma MG-63 cells proved the biocompatibility of the scaffolds. Furthermore, scaffolds were loaded with model drug compounds for guided hMSC differentiation. Different release kinetic models were evaluated for adenosine 5′-triphosphate (ATP) and suramin, and data showed a sustained release behavior over four days.

Enhanced Osteogenesis and Angiogenesis for Putative Bone Grafts by Activating Purinergic Receptor Signaling During Mesenchymal Stem Cell Differentiation (2019)

Tobiasch, Edda ; Bröker, Vanessa ; Shoushrah, Sarah ; Schulze, Margit

Sustainable Extraction and Characterisation of Bioactive Compounds from Horse Chestnut Seed Coats for the Development of Bio-Based Additives (2019)

Havelt, Thomas ; Brettschneider, Sarah ; Do, Xuan Tung ; Korte, Imke ; Kreyenschmidt, Judith ; Schmitz, Michaela

Background: To protect renewable packaging materials against autoxidation and decomposition when substituting harmful synthetic stabilizers with bioactive and bio-based compounds, extracts from Aesculus hippocastanum L. seeds were evaluated. The study objectives were to determine the antioxidant efficacy of bioactive compounds in horse chestnut seeds with regard to different seed fractions, improve their extraction, and to evaluate waste reuse. Methods: Different extraction techniques for field samples were evaluated and compared with extracts of industrial waste samples based on total phenolic content and total antioxidant capacity (2,2’-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS)). The molecular weight distribution and absorbance in ultraviolet range (UV) of seed coat extracts were determined, and the possibility of extracts containing proanthocyanidins was examined. Results: Seed coat extracts show a remarkable antioxidant activity and a high UV absorbance. Passive extractions are efficient and much less laborious. Applying waste product seed coats leads to a reduced antioxidant activity, total phenolic content, and UV absorbance compared to the field sample counterparts. In contrast to peeled seed extracts, all seed coat extracts contain proanthocyanidins. Discussion: Seed coats are a potential source of bioactive compounds, particularly regarding sustainable production and waste reuse. With minimum effort, highly bioactive extracts with high potential as additives can be prepared.

Behördliche Anforderungen an ALB Spürhunde - ein Erfahrungsbericht (2019)

Kaul, Peter ; Makarow, Ramona ; Nüßer, Frank

Das Problem der kleinen Mengen - Auswirkung auf Training und Qualifizierung (2019)

Becher, Christopher

Dem lieben Gott ins Handwerk pfuschen: Risiken und Chancen der Gentechnik (2004)

Weisshaar, Maria-Paz

Die Diskussion über Nutzen und Risiken der Biound Gentechnik beherrschte die Jahre von 1998 bis 2001. Die „grüne Gentechnik“ kämpfte auch 1997 gegen wachsende Widerstände. Erst als sich im Jahr 2001 die Medien mit der „roten“ Gentechnik befassten, sank der Anteil kritischer Vorbehalte und stieg die Akzeptanz gegenüber gentechnisch herstellten Medikamenten in der Bevölkerung. Die Entschlüsselung der menschlichen Erbanlage und die Diskussion um das Klonen von Menschen sowie die Forschung mit embryonalen Stammzellen führte neue Aspekte in die öffentliche Diskussion ein. Die Debatte findet seither auf allen politischen Ebenen statt. Im Zusammenhang mit der Genforschung werden in den Medien immer häufiger Moral und Ökonomie gegenübergestellt und gegeneinander abgewogen. In diesem Wirrwarr von unterschiedlichen und häufig auch widerstreitenden Interessen ist es nicht einfach, sich zurechtzufinden und schließlich zu einer eigenen Position zu gelangen. Umso wichtiger ist daher eine nüchterne Darstellung der Sachverhalte.

Characterization of horse-derived induced pluripotent stem cells (2019)

Bröker, Vanessa ; Hielscher, Dorothee ; Pansky, Andreas ; Pfannkuche, Kurt ; Tobiasch, Edda

Low-Input Crops as Lignocellulosic Feedstock for Second-Generation Biorefineries and the Potential of Chemometrics in Biomass Quality Control (2019)

Alzagameem, Abla ; Bergs, Michel ; Do, Xuan Tung ; Klein, Stephanie Elisabeth ; Rumpf, Jessica ; Larkins, Michael ; Monakhova, Yulia ; Pude, Ralf ; Schulze, Margit

Lignocellulose feedstock (LCF) provides a sustainable source of components to produce bioenergy, biofuel, and novel biomaterials. Besides hard and soft wood, so-called low-input plants such as Miscanthus are interesting crops to be investigated as potential feedstock for the second generation biorefinery. The status quo regarding the availability and composition of different plants, including grasses and fast-growing trees (i.e., Miscanthus, Paulownia), is reviewed here. The second focus of this review is the potential of multivariate data processing to be used for biomass analysis and quality control. Experimental data obtained by spectroscopic methods, such as nuclear magnetic resonance (NMR) and Fourier-transform infrared spectroscopy (FTIR), can be processed using computational techniques to characterize the 3D structure and energetic properties of the feedstock building blocks, including complex linkages. Here, we provide a brief summary of recently reported experimental data for structural analysis of LCF biomasses, and give our perspectives on the role of chemometrics in understanding and elucidating on LCF composition and lignin 3D structure.

Short-range structural correlations in amorphous 2D polymers (2019)

Alexa, Patrick ; Oligschleger, Christina ; Gröger, Pascal ; Morchutt, Claudius ; Vyas, Vijay ; Lotsch, Bettina ; Schön, J. Christian ; Gutzler, Rico ; Kern, Klaus

Development of an Advanced Dynamic Microindentation System to Determine Local Viscoelastic Properties of Polymers (2019)

Ramakers-van Dorp, Esther ; Haenel, Thomas ; Ciongwa, Dominik ; Möginger, Bernhard ; Hausnerova, Berenika

This study presents a microindentation system which allows spatially resolved local as well as bulk viscoelastic material information to be obtained within one instrument. The microindentation method was merged with dynamic mechanical analysis (DMA) for a tungsten cone indenter. Three tungsten cone indenters were investigated: tungsten electrode, tungsten electrode + 2% lanthanum, and tungsten electrode + rare earth elements. Only the tungsten electrode + 2% lanthanum indenter showed the sinusoidal response, and its geometry remained unaffected by the repeated indentations. Complex moduli obtained from dynamic microindentation for high-density polyethylene, polybutylene terephthalate, polycarbonate, and thermoplastic polyurethane are in agreement with the literature. Additionally, by implementing a specially developed x-y-stage, this study showed that dynamic microindentation with a tungsten cone indenter was an adequate method to determine spatially resolved local viscoelastic surface properties.

Process-dependent structural and deformation properties of extrusion blow molding parts (2019)

Ramakers-van Dorp, Esther ; Blume, Christian ; Haedecke, Tobias ; Pata, Vladimir ; Reith, Dirk ; Bruch, Olaf ; Möginger, Bernhard ; Hausnerova, Berenika

In vitro discrimination and classification of Microbial Flora of Poultry using two dispersive Raman spectrometers (microscope and Portable Fiber-Optic systems) in tandem with chemometric analysis (2019)

Jaafreh, Sawsan ; Valler, Ole ; Kreyenschmidt, Judith ; Günther, Klaus ; Kaul, Peter

Disorders of ketone body transport and utilization as a cause of recurrent metabolic acidosis: succinyl-coenzyme A: 3-oxoacyl coenzyme A transferase (SCOT) deficiency (mutations in the OXCT1 gene) and monocarboxylate transporter 1 (MCT1) deficiency (2019)

Roloff, S. ; Stübbe, L. ; Gemperle-Britschgi, C. ; Yamamoto, R. ; Hennermann, J. ; Weinhold, N. ; Sass, J. O.

Antioxidant activity of unmodified kraft and organosolv lignins to be used as sustainable components for polyurethane coatings (2019)

Klein, Stephanie E. ; Rumpf, Jessica ; Alzagameem, Abla ; Rehahn, Matthias ; Schulze, Margit

Synthesis and Characterization of PVP-Stabilized Palladium Nanoparticles by XRD, SAXS, SP-ICP-MS, and SEM (2019)

Walbrück, Katharina ; Kuellmer, Fabian ; Witzleben, Steffen ; Guenther, Klaus

Due to increased emissions of palladium nanoparticles in recent years, it is important to develop analytical techniques to characterize these particles. The synthesis of defined and stable particles plays a key role in this process, as there are not many materials commercially available yet which could act as reference materials. Polyvinylpyrrolidone- (PVP-) stabilized palladium nanoparticles were synthesized through the reduction of palladium chloride by tetraethylene glycol (TEG) in the presence of KOH. Four different methods were used for particle size analysis of the palladium nanoparticles. Palladium suspensions were analyzed by scanning electron microscopy (SEM), small angle X-ray scattering (SAXS), single-particle ICP-MS (SP-ICP-MS), and X-ray diffraction (XRD). Secondary particles between 30 nm and 130 nm were detected in great compliance with SAXS and SP-ICP-MS. SEM analysis showed that the small particulates tend to form agglomerates.

Antimicrobial Activity of Lignin and Lignin-Derived Cellulose and Chitosan Composites Against Selected Pathogenic and Spoilage Microorganisms (2019)

Alzagameem, Abla ; Klein, Stephanie Elisabeth ; Bergs, Michel ; Do, Xuan Tung ; Korte, Imke ; Dohlen, Sophia ; Hüwe, Carina ; Kreyenschmidt, Judith ; Kamm, Birgit ; Larkins, Michael ; Schulze, Margit

The antiradical and antimicrobial activity of lignin and lignin-based films are both of great interest for applications such as food packaging additives. The polyphenolic structure of lignin in addition to the presence of O-containing functional groups is potentially responsible for these activities. This study used DPPH assays to discuss the antiradical activity of HPMC/lignin and HPMC/lignin/chitosan films. The scavenging activity (SA) of both binary (HPMC/lignin) and ternary (HPMC/lignin/chitosan) systems was affected by the percentage of the added lignin: the 5% addition showed the highest activity and the 30% addition had the lowest. Both scavenging activity and antimicrobial activity are dependent on the biomass source showing the following trend: organosolv of softwood > kraft of softwood > organosolv of grass. Testing the antimicrobial activities of lignins and lignin-containing films showed high antimicrobial activities against Gram-positive and Gram-negative bacteria at 35 °C and at low temperatures (0-7 °C). Purification of kraft lignin has a negative effect on the antimicrobial activity while storage has positive effect. The lignin release in the produced films affected the activity positively and the chitosan addition enhances the activity even more for both Gram-positive and Gram-negative bacteria. Testing the films against spoilage bacteria that grow at low temperatures revealed the activity of the 30% addition on HPMC/L1 film against both B. thermosphacta and P. fluorescens while L5 was active only against B. thermosphacta. In HPMC/lignin/chitosan films, the 5% addition exhibited activity against both B. thermosphacta and P. fluorescens.

System Accuracy Assessment of a Blood Glucose Meter With Wireless Internet Access Associated With Unusual Hypoglycemia Patterns in Clinical Trials (2019)

Pfützner, Andreas ; Demircik, Filiz ; Kirsch, Valeria ; Pfützner, Johannes ; Strobl, Stephanie ; Hanna, Mina ; Spatz, Jan ; Pfützner, Anke H.

BACKGROUND In recent randomized clinical trials, an unusual reporting pattern of glycemic data and hypoglycemic events potentially related to an internet enabled blood glucose meter (MyGlucoHealth, BGM) was observed. Therefore, this clinical study was conducted to evaluate the system accuracy of the BGM in accordance with the ISO15197:2015 guidelines with additional data collection. METHODS To investigate system accuracy, 10 of 3088 devices and 6 of 23 strip lots, used in the trials, were selected by a randomization procedure and a standard repeatability assessment. YSI 2300 STAT Plus was used as the standard reference method. The samples were distributed as per the ISO15197:2015 recommendations with 20 additional samples in the hypoglycemic range. Each sample was tested with 6 devices and 6 strip lots with double determinations. RESULTS Overall, 121 subjects with blood glucose values 26-423 mg/dL were analyzed, resulting in 1452 data points. In all, 186/1452 readings (12.8%) did not meet the ISO acceptance criteria. Data evaluated according to the FDA guidelines showed that 336/1452 (23.1%) readings did not meet the acceptance criteria. A clear bias toward elevated values was observed for BG <100 mg/dL (MARD: 11.0%). CONCLUSIONS The results show that the BGM, although approved according to standard regulatory guidelines, did not meet the level of analytical accuracy required for clinical treatment decisions according to ISO 15197:2015 and FDA requirements. In general, caution should be exercised before selection of BGMs for patients and in clinical trials.

Laboratory Evaluation of Linearity, Repeatability, and Hematocrit Interference With an Internet-Enabled Blood Glucose Meter (2019)

Demircik, Filiz ; Kirsch, Valeria ; Ramljak, Sanja ; Vogg, Mario ; Pfützner, Anke H. ; Pfützner, Andreas

BACKGROUND In recent clinical trials, use of the MyGlucoHealth blood glucose meter (BGM) and electronic diary was associated with an unusual reporting pattern of glycemic data and hypoglycemic events. Therefore, the performance of representative BGMs used by the patients was investigated to assess repeatability, linearity, and hematocrit interference in accordance with regulatory guidelines. METHOD Ten devices and 6 strip lots were selected using standard randomization and repeatability procedures. Venous heparinized blood was drawn from healthy subjects, immediately aliquoted and adjusted to 5 target blood glucose (BG) ranges for the repeatability and 11 BG concentrations for the linearity tests. For the hematocrit interference test, each sample within 5 target BG ranges was split into 5 aliquots and adjusted to hematocrit levels across the acceptance range. YSI 2300 STAT Plus was used as the laboratory reference method in all experiments. RESULTS Measurement repeatability or precision was acceptable across the target BG ranges for all devices and strip lots with coefficient of variation (CV) between 3.4-9.7% (mean: 5.7%). Linearity was shown by a correlation coefficient of .991; however, a positive bias was seen for BG <100 mg/dL (86% measurements did not meet ISO15197:2015 acceptance criteria). Significant hematocrit interference (up to 20%) was observed for BG >100 mg/dL (ISO15197:2015 acceptance criteria: ±10%), while the results were acceptable for BG <100 mg/dL. CONCLUSIONS The BGM met repeatability requirements but demonstrated a significant measurement bias in the low BG range. In addition, it failed the ISO15197:2015 criteria for hematocrit interference.

Faszinosum Spürhunde – Dem Geruch auf der Spur (2019)

Im September 2018 fand in Rheinbach das 4. Symposium für Odorologie – Faszinosum Spürhunde unter dem Titel „Dem Geruch auf der Spur“ statt. Mehr als 300 Fachleute aus Wissenschaft, Behörden, Militär, Zoll, Hilfsorganisationen, Jagd und Sport aus aller Welt trafen sich zu einem fachlichen Austausch.

Querempfindlichkeiten bei der Quarzanalytik mittels FTIR (2019)

Heck, Jonas ; Mattenklott, Markus

Aspartoacylase Deficiency (Canavan Disease, N-Acetylaspartic Aciduria) (2019)

Sass, Jörn Oliver ; Knerr, Ina

CD is a rare, autosomal recessive neurometabolic disorder with often devastating clinical consequences. It typically presents in early infancy. Clinical symptoms and MRI-based findings are chronic neurological deterioration with irritability and severe global developmental delay, loss of early milestones, macrocephaly, and seizures together with white matter abnormalities in the brain (“leukodystrophy”). CD is biochemically characterized by a deficiency of aspartoacylase along with the accumulation of NAA in the brain and in body fluids, particularly in urine. In the majority of CD patients, the disease leads to early death. As there is no cure for this condition, management of affected children and their families is symptom orientated and supportive and includes a multidisciplinary medical team.

Hochschuldidaktik - Reden über Verantwortung (2019)

Groß, Iris ; Lehmann, Klaus

An der Hochschule Bonn‐Rhein‐Sieg setzten sich Chemiestudenten freiwillig parallel zum eigentlichen Fachstudium und fachübergreifend mit dem Begriff Nachhaltigkeit auseinander. Die Lehrveranstaltungen zeigen ihnen die gesellschaftlichen Bezüge naturwissenschaftlicher Inhalte und bringen sie dazu, ihr Selbstverständnis als Chemiker zu überdenken.

Effects of Silicon Compounds on Biomineralization, Osteogenesis, and Hard Tissue Formation (2019)

Götz, Werner ; Tobiasch, Edda ; Witzleben, Steffen ; Schulze, Margit

Bioinspired stem cell-based hard tissue engineering includes numerous aspects: The synthesis and fabrication of appropriate scaffold materials, their analytical characterization, and guided osteogenesis using the sustained release of osteoinducing and/or osteoconducting drugs for mesenchymal stem cell differentiation, growth, and proliferation. Here, the effect of silicon- and silicate-containing materials on osteogenesis at the molecular level has been a particular focus within the last decade. This review summarizes recently published scientific results, including material developments and analysis, with a special focus on silicon hybrid bone composites. First, the sources, bioavailability, and functions of silicon on various tissues are discussed. The second focus is on the effects of calcium-silicate biomineralization and corresponding analytical methods in investigating osteogenesis and bone formation. Finally, recent developments in the manufacturing of Si-containing scaffolds are discussed, including in vitro and in vivo studies, as well as recently filed patents that focus on the influence of silicon on hard tissue formation.

Identifizierung und Charakterisierung bioaktiver Inhaltsstoffe in Thymian (2018)

Havelt, Thomas ; Schmitz, Michaela

Bei Thymian (Thymus vulgaris) handelt es sich um eine sehr varietätenreiche Art, die aufgrund ihres Gehaltes an therapeutisch wirksamen Inhaltsstoffen als Arzneipflanze monographiert ist. Insbesondere das ätherische Öl mit dem Hauptbestandteil Thymol (ca. 50%) hat eine hohe antioxidative Wirkung. Ziel ist es, dieses Potential als nachhaltig produzierte Additive zu nutzen. Hierfür eignen sich antioxidativ bzw. antimikrobiell wirksame sowie UV-absorbierende Substanzen, die das Produkt bei Zusatz vor oxidativem Stress, mikrobiellem Abbau und Qualitätsverlust schützen. Hierzu werden zunächst sechs Varianten auf verschiedene Parameter analysiert, um die potenteste Variante auszuwählen. Auf diese Variante wird sich die weitere Forschung konzentrieren. Daher wird das ätherische Öl durch azeotrope Destillation extrahiert und mittels GCMS analysiert. In Extrakten werden zudem das AP und Absorptionsverhalten bestimmt. Auch die chemische Zusammensetzung des Extrakts sowie die flüchtigen Stoffe des Thymians werden untersucht. Generell gibt es wenig qualitative, teilweise jedoch quantitative Unterschiede: Eine Variante weist u.a. einen deutlich höheren Thymolgehalt im Öl (ca. 65 %) und ein hohes hydrophiles AP auf. Somit ist eine vielversprechende Variante für die weitere Entwicklung und Optimierung bioaktiver Additive gefunden.

Mass Spectrometry: Pyrolysis (2019)

Twyman, Richard M. ; Kusch, Peter

Creep behavior of short fiber reinforced composites: Effects of fiber orientation and fiber matrix adhesion (2016)

Möginger, Bernhard ; Hausnerova, Berenika

Miscanthus x giganteus Stem Versus Leaf-Derived Lignins Differing in Monolignol Ratio and Linkage (2019)

Bergs, Michel ; Völkering, Georg ; Kraska, Thorsten ; Pude, Ralf ; Do, Xuan Tung ; Kusch, Peter ; Monakhova, Yulia ; Konow, Christopher ; Schulze, Margit

As a renewable, Miscanthus offers numerous advantages such as high photosynthesis activity (as a C4 plant) and an exceptional CO2 fixation rate. These properties make Miscanthus very attractive for industrial exploitation, such as lignin generation. In this paper, we present a systematic study analyzing the correlation of the lignin structure with the Miscanthus genotype and plant portion (stem versus leaf). Specifically, the ratio of the three monolignols and corresponding building blocks as well as the linkages formed between the units have been studied. The lignin amount has been determined for M. x giganteus (Gig17, Gig34, Gig35), M. nagara (NagG10), M. sinensis (Sin2), and M. robustus (Rob4) harvested at different time points (September, December, and April). The influence of the Miscanthus genotype and plant component (leaf vs. stem) has been studied to develop corresponding structure-property relationships (i.e., correlations in molecular weight, polydispersity, and decomposition temperature). Lignin isolation was performed using non-catalyzed organosolv pulping and the structure analysis includes compositional analysis, Fourier transform infradred (FTIR), ultraviolet/visible (UV-Vis), hetero-nuclear single quantum correlation nuclear magnetic resonsnce (HSQC-NMR), thermogravimetric analysis (TGA), and pyrolysis gaschromatography/mass spectrometry (GC/MS). Structural differences were found for stem and leaf-derived lignins. Compared to beech wood lignins, Miscanthus lignins possess lower molecular weight and narrow polydispersities (<1.5 Miscanthus vs. >2.5 beech) corresponding to improved homogeneity. In addition to conventional univariate analysis of FTIR spectra, multivariate chemometrics revealed distinct differences for aromatic in-plane deformations of stem versus leaf-derived lignins. These results emphasize the potential of Miscanthus as a low-input resource and a Miscanthus-derived lignin as promising agricultural feedstock.

Analytical pyrolysis (2019)

Analytical pyrolysis deals with the structural identification and quantitation of pyrolysis products with the ultimate aim of establishing the identity of the original material and the mechanisms of its thermal decomposition. The pyrolytic process is carried out in a pyrolyzer interfaced with analytical instrumentation such as gas chromatography (GC), mass spectrometry (MS), gas chromatography coupled with mass spectrometry (GC/MS), or with Fourier-transform infrared spectroscopy (GC/FTIR). By measurement and identification of pyrolysis products, the molecular composition of the original sample can often be reconstructed.This book is the outcome of contributions by experts in the field of pyrolysis and includes applications of the analytical pyrolysis-GC/MS to characterize the structure of synthetic organic polymers and lignocellulosic materials as well as cellulosic pulps and isolated lignins, solid wood, waste particle board, and bio-oil. The thermal degradation of cellulose and biomass is examined by scanning electron micrography, FTIR spectroscopy, thermogravimetry (TG), differential thermal analysis, and TG/MS. The calorimetric determination of high heating values of different raw biomass, plastic waste, and biomass/plastic waste mixtures and their by-products resulting from pyrolysis is described.

Functional polysaccharide hydrogels through chemical derivatization of agarose (2017)

Gericke, Martin ; Witzler, Markus ; Schulze, Margit ; Heinze, Thomas

Fixed-dose combination of pioglitazone and glimepiride in the treatment of Type 2 diabetes mellitus (2007)

Forst, Thomas ; Pfützner, Andreas

Type 2 diabetes is characterized by impaired insulin sensitivity and disturbances in β-cell function. While glimepiride stimulates β-cell secretion and leads to a reduction of blood glucose levels, pioglitazone activates peroxisome proliferator-activated receptor-γ and improves insulin resistance. Combining these two modes of action has been shown to improve glucose and lipid metabolism, and to improve the overall cardiovascular risk in patients with Type 2 diabetes. The combination of glimepiride and pioglitazone is generally well tolerated and a fixed combination may lead to an improved compliance in patients. The purpose of this review is to evaluate the clinical data that has been published on this combination, appearing to represent a convenient way to obtain therapeutic targets in patients with Type 2 diabetes mellitus.

XRPD Untersuchung von kathodischen Ablagerungen bei der PEM Elektrolyse von Leitungswasser zur in situ Ozonung von Brauchwasser (2018)

Grimmig, R. ; Breuer, A. ; Witzleben, S.

Möglichkeiten und Grenzen der Baustoffanalytik und anwendungstechnische Prüfungen an Objekten (2018)

Witzleben, Steffen

Untersuchungen zur Hydrophobierung von Miscanthus X giganteus für den Einsatz in Dämmstoffsystemen (2018)

Walbrück, K. ; Witzleben, S.

Untersuchungen zum Einfluss von chemischen Aktivatoren und Templaten auf die Zementhydratation (2018)

Witzleben, S. T. ; Leiendecker, A. ; Thelen, M.

Lignin-Depolymerisation via UV-Photolyse und Titandioxid-Photokatalyse (2017)

Schulze, M. ; Witzleben, S. ; Nietsch, A. ; Jung, C. ; Do, X. T.

Novel Hydroxyapatite/Agarose Composites for Bone Tissue Engineering and Drug Delivery (2017)

Schulze, M. ; Ottensmeyer, P. ; Witzleben, S. ; Tobiasch, E. ; Gericke, M. ; Heinze, T. ; Witzler, M.

Synthese von Lignin-basierten flexiblen, hydrophoben Polyurethan-Beschichtungen (2017)

Schulze, M. ; Rumpf, J. ; Rehahn, M. ; Klein, S. E. ; Witzleben, S.

Einfluss von Isolationsprozess und Ressource auf die Lignin-Struktur: Organosolv-Lignine erhalten aus Miscanthus und Buchenholz (2017)

Schulze, M. ; El Khaldi-Hansen, B. ; Kraska, T. ; Pude, R. ; Kamm, B. ; Bergs, M. ; Witzleben, S.

Environmentally Benign Antioxidants: Lignin-based Materials for Food Packaging Applications (2017)

Schulze, M. ; El Khaldi-Hansen, B. ; Dreier, T. ; Alzagameem, A. ; Kamm, B. ; Braun, C. ; Kreyenschmidt, J.

Einfluss von Miscanthus-Genotyp und Erntezeit auf Gehalt und Struktur von Lignin aus Organosolv-Verfahren (2019)

Bergs, Michel

Miscanthus bietet als nachwachsende Industrie- und Energiepflanze zahlreiche Vorteile, die neben den direkten landwirtschaftlichen Anwendungen wie Verbrennung und Tiereinstreu auch eine stoffliche Nutzung im chemischen Bereich zulassen. Als C4-Pflanze mit gesteigerter Photosynthese-Aktivität weist Miscanthus zudem eine hohe CO2-Fixierrate auf. Aufgrund des geringen Kultivierungsaufwandes sowie der hohen Erträge bietet sich Miscanthus als ausgesprochen attraktiver Rohstoff für die Produktion erneuerbarer Kraftstoffe und Chemikalien an, welche mittels thermo-chemischer Umwandlung gewonnen werden.

Comparative study on serum-induced arthritis in the temporomandibular and limb joint of mice (2019)

Safi, Sema ; Frommholz, David ; Reimann, Susanne ; Götz, Werner ; Bourauel, Christoph ; Neumann, Anna-Lena ; Hoerauf, Achim ; Illges, Harald ; Safi, Ali-Farid ; Jäger, Andreas ; Hübner, Marc P. ; Gölz, Lina

Purinergic signaling in mesenchymal stem cell differentiation (2018)

Tobiasch, Edda ; Hielscher, Dorothee ; Ottensmeyer, Patrick ; Babczyk, Patrick ; Zhang, Yu ; Schulze, Margit

Chemie für Dummies. Das Lehrbuch (2019)

Ortanderl, Stefanie ; Ritgen, Ulf

Chemie ist viel einfacher, als es häufig heißt. Dieses Buch soll dazu beitragen, ihr Interesse an diesem Fach zu wecken oder zu vertiefen. Alle grundlegenden Prinzipien der Chemie werden nachvollziehbar dargestellt. Querbezüge und Zusammenhänge zwischen den verschiedenen Fachgebieten werden gezeigt. Sie werden keine Formel finden, deren Herleitung Sie nicht nachvollziehen können. Am Ende fast jeden Kapitels gibt es Übungsaufgaben. Ausführliche Lösungen gibt es natürlich auch. Das sollte nicht nur für die Prüfungen der ersten Semester reichen, sondern Ihnen auch ein sicheres Fundament für Ihr weiteres Studium bieten.

Resilienz des Deutsch-Französischen Eisenbahn-Hochgeschwindigkeitsverkehrs - REHSTRAIN, Teilvorhaben 6: "Abstandsfähige Sicherheitsmaßahmen" : Abschlussbericht (2018)

Maurer, Stephan ; Kaul, Peter

Abschlussbericht zum FHprofUnt-Projekt Forensische Analyse singulärer Genome mittels WGA (Akronym: ForWArd) (2018)

Jäger, Richard

Detection of spoilage associated bacteria using Raman-microspectroscopy combined with multivariate statistical analysis (2019)

Klein, Daniel ; Breuch, René ; Mark, Sune von der ; Wickleder, Claudia ; Kaul, Peter

Reporting of light irradiation conditions in 300 laboratory studies of resin-composites (2019)

Watts, David C. ; Kaiser, Christina ; O'Neill, Catherine ; Price, Richard Bengt

Investigation of volatile organic compounds emitted by Anoplophora glabripennis (Moschulsky) using thermal desorption and gas chromatography-mass spectrometry (2019)

Makarow, Ramona ; Schaefer, Sara ; Stephan, Albrecht ; Robert, Simon ; Schütz, Stefan ; Kaul, Peter

Supervised classification of monomodal and multimodal hyperspectral data in vibrational microspectroscopy: A comprehensive comparison (2019)

Pomrehn, Christoph ; Klein, Daniel ; Kolb, Andreas ; Kaul, Peter ; Herpers, Rainer

The application of Raman and infrared (IR) microspectroscopy is leading to hyperspectral data containing complementary information concerning the molecular composition of a sample. The classification of hyperspectral data from the individual spectroscopic approaches is already state-of-the-art in several fields of research. However, more complex structured samples and difficult measuring conditions might affect the accuracy of classification results negatively and could make a successful classification of the sample components challenging. This contribution presents a comprehensive comparison in supervised pixel classification of hyperspectral microscopic images, proving that a combined approach of Raman and IR microspectroscopy has a high potential to improve classification rates by a meaningful extension of the feature space. It shows that the complementary information in spatially co-registered hyperspectral images of polymer samples can be accessed using different feature extraction methods and, once fused on the feature-level, is in general more accurately classifiable in a pattern recognition task than the corresponding classification results for data derived from the individual spectroscopic approaches.

Functional Roles of O-Glycosylation (2018)

Breloy, Isabelle ; Hanisch, Franz-Georg

O-Glycosylation in general has impact on a diversity of biological processes covering cellular aspects (targeted transport of glycoproteins), molecular aspects (protein conformation, resistance to proteolysis), and aspects involved in cellular communication (cell-cell and cell-matrix interaction).

Unmodified kraft lignin isolated at room temperature from aqueous solution for preparation of highly flexible transparent polyurethane coatings (2018)

Klein, Stephanie Elisabeth ; Rumpf, Jessica ; Kusch, Peter ; Albach, Rolf ; Rehahn, Matthias ; Witzleben, Steffen ; Schulze, Margit

Polyurethane (PU) coatings were successfully produced using unmodified kraft lignin (KL) as an environmentally benign component in contents of up to 80 wt%. Lignin samples were precipitated from industrial black liquor in aqueous solution working at room temperature and different pH levels (pH 2 to pH 5). Lignins were characterized by UV-Vis, FTIR, pyrolysis-GC/MS, SEC and 31P-NMR. Results show a correlation between pH level, OH number and molecular weight Mw of isolated lignins. Lignin-based polyurethane coatings were prepared in an efficient one step synthesis dissolving lignin in THF and PEG425 in an ultrasonic bath followed by addition of 4,4-diphenylmethanediisocyanate (MDI) and triethylamine (TEA). Crosslinking was achieved under very mild conditions (1 hour at room temperature followed by 3 hours at 35 °C). The resulting coatings were characterized regarding their physical properties including ATR-IR, TGA, optical contact angle, light microscopy, REM-EDX and AFM data. Transparent homogeneous films of high flexibility resulted from lignins isolated at pH 4, possessing a temperature resistance up to 160 °C. Swelling tests revealed a resistance against water. Swelling in DMSO depends on index, pH of precipitation and catalyst utilization for PU preparation. According to AFM studies, surface roughness is between 10 and 28 nm.

Small Molecules Enhance Scaffold-Based Bone Grafts via Purinergic Receptor Signaling in Stem Cells (2018)

Ottensmeyer, Patrick Frank ; Witzler, Markus ; Schulze, Margit ; Tobiasch, Edda

The need for bone grafts is high, due to age-related diseases, such as tumor resections, but also accidents, risky sports, and military conflicts. The gold standard for bone grafting is the use of autografts from the iliac crest, but the limited amount of accessible material demands new sources of bone replacement. The use of mesenchymal stem cells or their descendant cells, namely osteoblast, the bone-building cells and endothelial cells for angiogenesis, combined with artificial scaffolds, is a new approach. Mesenchymal stem cells (MSCs) can be obtained from the patient themselves, or from donors, as they barely cause an immune response in the recipient. However, MSCs never fully differentiate in vitro which might lead to unwanted effects in vivo. Interestingly, purinergic receptors can positively influence the differentiation of both osteoblasts and endothelial cells, using specific artificial ligands. An overview is given on purinergic receptor signaling in the most-needed cell types involved in bone metabolism-namely osteoblasts, osteoclasts, and endothelial cells. Furthermore, different types of scaffolds and their production methods will be elucidated. Finally, recent patents on scaffold materials, as wells as purinergic receptor-influencing molecules which might impact bone grafting, are discussed.

Introductory Chapter: Analytical Pyrolysis – Gas Chromatography/Mass Spectrometry of Polymeric Materials (2018)

Kusch, Peter

According to the International Union of Pure and Applied Chemistry (IUPAC) recommendation, analytical pyrolysis (Py) is defined as the characterization in an inert atmosphere of a material or a chemical process by a chemical degradation reaction(s) induced by thermal energy [1]. Thermal degradation under controlled conditions is often used as a part of an analytical procedure, either to render a sample into a suitable form for subsequent analysis by gas chromatography (GC), mass spectrometry (MS), gas chromatography coupled with the mass spectrometry (GC/MS), with the Fourier-transform infrared spectroscopy (GC/FTIR), or by direct monitoring as an analytical technique in its own right [2].

Introductory Chapter: Gas Chromatography - The Most Versatile Analytical Technique (2018)

Kusch, Peter

Gas chromatography (GC) is a type of chromatography. According to the International Union of Pure and Applied Chemistry (IUPAC) recommendation, gas chromatography is defined as a separation technique in which the mobile phase is a gas. Gas chromatography is always carried out in a column [1]. GC is a separation and detection method for sample mixtures, whose components can be volatilized without thermal decomposition.

Next generation sequencing of RNA reveals novel targets of resveratrol with possible implications for Canavan disease (2019)

Dembic, Maja ; Andersen, Henriette S. ; Bastin, Jean ; Doktor, Thomas K. ; Corydon, Thomas J. ; Sass, Jörn Oliver ; Costa, Alexandra Lopes ; Djouadi, Fatima ; Andresen, Brage S.

Resveratrol (RSV) is a small compound first identified as an activator of sirtuin 1 (SIRT1), a key factor in mediating the effects of caloric restriction. Since then, RSV received great attention for its widespread beneficial effects on health and in connection to many diseases. RSV improves the metabolism and the mitochondrial function, and more recently it was shown to restore fatty acid β-oxidation (FAO) capacities in patient fibroblasts harboring mutations with residual enzyme activity. Many of RSV's beneficial effects are mediated by the transcriptional coactivator PGC-1α, a direct target of SIRT1 and a master regulator of the mitochondrial fatty acid oxidation. Despite numerous studies RSV's mechanism of action is still not completely elucidated. Our aim was to investigate the effects of RSV on gene regulation on a wide scale, possibly to detect novel genes whose up-regulation by RSV may be of interest with respect to disease treatment. We performed Next Generation Sequencing of RNA on normal fibroblasts treated with RSV. To investigate whether the effects of RSV are mediated through SIRT1 we expanded the analysis to include SIRT1-knockdown fibroblasts. We identified the aspartoacylase (ASPA) gene, mutated in Canavan disease, to be strongly up-regulated by RSV in several cell lines, including Canavan disease fibroblasts. We further link RSV to the up-regulation of other genes involved in myelination including the glial specific transcription factors POU3F1, POU3F2, and myelin basic protein (MBP). We also observe a strong up-regulation by RSV of the riboflavin transporter gene SLC52a1. Mutations in SLC52a1 cause transient multiple acyl-CoA dehydrogenase deficiency (MADD). Our analysis of alternative splicing identified novel metabolically important genes affected by RSV, among which is particularly interesting the α subunit of the stimulatory G protein (Gsα), which regulates the cellular levels of cAMP through adenylyl cyclase. We conclude that in fibroblasts RSV stimulates the PGC-1α and p53 pathways, and up-regulates genes affecting the glucose metabolism, mitochondrial β-oxidation, and mitochondrial biogenesis. We further confirm that RSV might be a relevant treatment in the correction of FAO deficiencies and we suggest that treatment in other metabolic disorders including Canavan disease and MADD might be also beneficial.

A passenger flow oriented security and safety approach in international railway stations (2018)

Collart-Dutilleul, Simon ; Maurer, Stephan ; Bon, Philippe ; Kaul, Peter

In the context of the Franco-German research project Re(h)strain, this work focuses on a global system analysis integrating both safety and security analysis of international and/or urban railway stations. The Re(h)strain project focuses on terrorist attacks on high speed train systems and investigates prevention and mitigation measures to reduce the overall vulnerability and strengthen the system resilience. One main criterion regarding public transport issues is the number of passengers. For example, the railway station of Paris “Gare du Nord” deals with a bigger number of passengers than the biggest airport in the world (SNCF open Data 2014), the Atlanta airport, but in terms of passengers, it is only around the 23rd rank railway station in the world. Due to the enormous mass of people, this leads to the system approach of breaking out the station into several classes of zones, e.g. entrance, main hall, quays, trains, etc. All classes are analysed considering state-of-the-art parameters, like targets attractiveness, feasibility of attack, possible damage, possible mitigation and defences. Then, safety incidence of security defence is discussed in order to refine security requirement with regard to the considered zone. Finally, global requirements of security defence correlated to the corresponding class of zones are proposed.

Laserbohrverfahren zur Detektion verpackter Gefahrstoffe (2018)

Wild, Dominik

Gegenstand dieser Arbeit sind Untersuchungen zur Detektion von verpackten Gefahrstoffen wie beispielsweise Explosivstoffen. Hierzu wird in einem ersten Schritt die Verpackung mittels Laserbohrens durchdrungen, um anschließend den nun freiliegenden Gefahrstoff nachweisen zu können. Dies geschieht einerseits durch eine lasergestützte Probenahme und anschließende Detektion mit gängigen chemisch-analytischen Verfahren sowie direkt bei der Wechselwirkung zwischen Laser und Gefahrstoff mittels Ramanspektroskopie. Zudem werden schnelle in situ-Techniken im Hinblick auf ihre Eignung zur Überwachung des Laserbohrprozesses untersucht. Hier werden kostengünstige und kompakte Sensortechniken (Messung der Prozessgase durch Halbleitergassensoren, Messung des Luftschalls mittels Kondensatormikrofon) mit aufwendigeren und komplexeren spektroskopischen Verfahren (Plasma- und Ramanspektroskopie) bewertend verglichen. Anhand ausgewählter Modellsysteme in verkleinertem Maßstab werden die unterschiedlichen Verfahren unter Verwendung gängiger Verpackungs- und Hüllenmaterialien sowie anhand ausgewählter Explosivstoffe charakterisiert. Für das Laserverfahren kommen gepulste Nd:YAG Laser mit unterschiedlichen Emissionswellenlängen zum Einsatz.

Determination of sinapine in rapeseed pomace extract: Its antioxidant and acetylcholinesterase inhibition properties (2019)

Yates, Kyari ; Pohl, Franziska ; Busch, Maike ; Mozer, Annika ; Watters, Louis ; Shiryaev, Andrey ; Kong Thoo Lin, Paul

Qualitätssicherung in der Forschung (2018)

Pohl, Barbara ; Pomp, Jürgen

Die Freiheit in Forschung und Lehre ist zusammen mit der Wissenschaftsfreiheit eines der bürgerlichen Grundrechte in Deutschland. Aber die Forschungsfreiheit kann nicht grenzenlos sein. Industrie wie akademische Institute müssen ihre Entwicklungen dokumentieren. Nur so ist ein Stoff später für die Vermarktung zulassungsfähig und nur so lässt sich belegen, wer die Urheberrechte daran hat.

Cathepsin B: Active Site Mapping with Peptidic Substrates and Inhibitors (2019)

Schmitz, Janina ; Gilberg, Erik ; Löser, Reik ; Bajorath, Jürgen ; Bartz, Ulrike ; Gütschow, Michael

Lignocellulosic Biomass as Source for Lignin-Based Environmentally Benign Antioxidants (2018)

Alzagameem, Abla ; El Khaldi-Hansen, Basma ; Büchner, Dominik ; Larkins, Michael ; Kamm, Birgit ; Witzleben, Steffen ; Schulze, Margit

Antioxidant activity is an essential aspect of oxygen-sensitive merchandise and goods, such as food and corresponding packaging, cosmetics, and biomedicine. Technical lignin has not yet been applied as a natural antioxidant, mainly due to the complex heterogeneous structure and polydispersity of lignin. This report presents antioxidant capacity studies completed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The influence of purification on lignin structure and activity was investigated. The purification procedure showed that double-fold selective extraction is the most efficient (confirmed by ultraviolet-visible (UV/Vis), Fourier transform infrared (FTIR), heteronuclear single quantum coherence (HSQC) and 31P nuclear magnetic resonance spectroscopy, size exclusion chromatography, and X-ray diffraction), resulting in fractions of very narrow polydispersity (3.2⁻1.6), up to four distinct absorption bands in UV/Vis spectroscopy. Due to differential scanning calorimetry measurements, the glass transition temperature increased from 123 to 185 °C for the purest fraction. Antioxidant capacity is discussed regarding the biomass source, pulping process, and degree of purification. Lignin obtained from industrial black liquor are compared with beech wood samples: antioxidant activity (DPPH inhibition) of kraft lignin fractions were 62⁻68%, whereas beech and spruce/pine-mixed lignin showed values of 42% and 64%, respectively. Total phenol content (TPC) of the isolated kraft lignin fractions varied between 26 and 35%, whereas beech and spruce/pine lignin were 33% and 34%, respectively. Storage decreased the TPC values but increased the DPPH inhibition.

The Unfolded Protein Response in Breast Cancer (2018)

McGrath, Eoghan ; Logue, Susan ; Mnich, Katarzyna ; Deegan, Shane ; Jäger, Richard ; Gorman, Adrienne ; Samali, Afshin

In 2018, in the US alone, it is estimated that 268,670 people will be diagnosed with breast cancer, and that 41,400 will die from it. Since breast cancers often become resistant to therapies, and certain breast cancers lack therapeutic targets, new approaches are urgently required. A cell-stress response pathway, the unfolded protein response (UPR), has emerged as a promising target for the development of novel breast cancer treatments. This pathway is activated in response to a disturbance in endoplasmic reticulum (ER) homeostasis but has diverse physiological and disease-specific functions. In breast cancer, UPR signalling promotes a malignant phenotype and can confer tumours with resistance to widely used therapies. Here, we review several roles for UPR signalling in breast cancer, highlighting UPR-mediated therapy resistance and the potential for targeting the UPR alone or in combination with existing therapies.

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