1,052 results on '"Martin Kaufmann"'
Search Results
202. Reply to the reviewers’ comments: Reviewer #1
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Martin Kaufmann
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- 2018
203. Introducing double polar heads to highly fluorescent Thiazoles: Influence on supramolecular structures and photonic properties
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T. Sachse, Dieter Weiß, Martin Kaufmann, Benjamin Dietzek, Felix Herrmann-Westendorf, Rainer Beckert, Martin Presselt, and Maximilian L. Hupfer
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chemistry.chemical_classification ,Materials science ,technology, industry, and agriculture ,Supramolecular chemistry ,02 engineering and technology ,Chromophore ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Fluorescence spectroscopy ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Biomaterials ,chemistry.chemical_compound ,Colloid and Surface Chemistry ,chemistry ,Chemical engineering ,Amphiphile ,Monolayer ,Self-assembly ,0210 nano-technology ,Thiazole ,Alkyl - Abstract
Hypothesis Supramolecular structures determine properties of optoelectronically active materials and can be tailored via the Langmuir-Blodgett (LB) technique. Interactions between dyes can cause high crystallinities of Langmuir monolayers, thus rendering retaining their integrity during the LB-deposition challenging. However, increasing degrees of freedom exclusively at the polar anchoring moieties of dyes might improve processability without perturbing the dye’s optoelectronic properties nor the function-determining crystallinity of the layer. Experiments (Amphiphilic) thiazole dyes without, with a mono-polar, and with a double-polar anchor were synthesized, whereas the two constituting polar moieties of the latter derivate are separated by a flexible alkyl chain. The supramolecular structures and crystallinities of Langmuir and LB monolayers were characterized by means of LB isotherms, atomic force microscopy and polarization-resolved fluorescence spectroscopy. Findings As compared to the mono-polar reference the introduction of a flexible double-polar head did not deteriorate UV-vis absorption, emission or electrochemical properties of the thiazole but significantly extended the range of constant compressibility modulus, thus indicating improved processability of the Langmuir monolayers. Indeed, AFM studies revealed that the integrity of the monolayers could be retained during LB-deposition. Additionally, also the underlying supramolecular structure of the chromophore moieties is largely identical to those obtained from the mono-polar reference thiazoles.
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- 2018
204. Veterinary Orthotics and Prosthetics
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Martin Kaufmann and Patrice M. Mich
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Orthodontics ,medicine.medical_specialty ,Amputation ,business.industry ,medicine.medical_treatment ,medicine ,Orthotics ,business ,Prosthesis ,Brace - Published
- 2018
205. The major glucosinolate hydrolysis product in rocket (Eruca sativa L.), sativin, is 1,3-thiazepane-2-thione: Elucidation of structure, bioactivity, and stability compared to other rocket isothiocyanates
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Jana Fechner, Corinna Herz, Evelyn Lamy, Franziska S. Hanschen, Daniela Eisenschmidt, Lothar W. Kroh, and Martin Kaufmann
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0301 basic medicine ,Molecular model ,Glucosinolates ,Eruca ,01 natural sciences ,Analytical Chemistry ,03 medical and health sciences ,chemistry.chemical_compound ,Hydrolysis ,Drug Stability ,Isothiocyanates ,Organic chemistry ,Aqueous solution ,biology ,010401 analytical chemistry ,Thiones ,General Medicine ,biology.organism_classification ,Tautomer ,0104 chemical sciences ,030104 developmental biology ,chemistry ,Glucosinolate ,Isothiocyanate ,Brassicaceae ,Food Science ,Sulforaphane - Abstract
Rocket is rich in glucosinolates and valued for its hot and spicy taste. Here we report the structure elucidation, bioactivity, and stability of the mainly formed glucosinolate hydrolysis product, namely sativin, which was formerly thought to be 4-mercaptobutyl isothiocyanate. However, by NMR characterization we revealed that sativin is in fact 1,3-thiazepane-2-thione, a tautomer of 4-mercaptobutyl isothiocyanate with 7-membered ring structure and so far unknown. This finding was further substantiated by conformation sampling using molecular modeling and total enthalpy calculation with density functional theory. During aqueous heat treatment sativin in general was quite stable, while the isothiocyanates erucin and sulforaphane were labile, having half-lives of 132 min and 56 min (pH 5, 100 °C), respectively. Moreover, using a WST-1 assay, we found that sativin did not reduce cell viability of HepG2 cells in a range of 0.3–30 µM, and, therefore, exhibited no cytotoxic effects in this cell line.
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- 2018
206. Towards a 3-D tomographic retrieval for the air-borne limb-imager GLORIA
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Lars Hoffmann, Martin Riese, Felix Friedl-Vallon, Martin Kaufmann, Hermann Oelhaf, Peter Preusse, and Jörn Ungermann
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Atmospheric Science ,lcsh:TA715-787 ,business.industry ,lcsh:Earthwork. Foundations ,Mesoscale meteorology ,Inversion (meteorology) ,Gimbal ,lcsh:Environmental engineering ,symbols.namesake ,Optics ,Fourier transform ,Homogeneous ,ddc:550 ,Radiance ,symbols ,Halo ,lcsh:TA170-171 ,Spectral resolution ,business ,Geology ,Remote sensing - Abstract
GLORIA (Gimballed Limb Observer for Radiance Imaging of the Atmosphere) is a new remote sensing instrument essentially combining a Fourier transform infrared spectrometer with a two-dimensional (2-D) detector array in combination with a highly flexible gimbal mount. It will be housed in the belly pod of the German research aircraft HALO (High Altitude and Long Range Research Aircraft). It is unique in its combination of high spatial and state-of-the art spectral resolution. Furthermore, the horizontal view angle with respect to the aircraft flight direction can be varied from 45° to 135°. This allows for tomographic measurements of mesoscale events for a wide variety of atmospheric constituents. In this paper, a tomographic retrieval scheme is presented, which is able to fully exploit the manifold radiance observations of the GLORIA limb sounder. The algorithm is optimized for massive 3-D retrievals of several hundred thousands of measurements and atmospheric constituents on common hardware. The new scheme is used to explore the capabilities of GLORIA to sound the atmosphere in full 3-D with respect to the choice of the flightpath and to different measurement modes of the instrument using ozone as a test species. It is demonstrated that the achievable resolution should approach 200 m vertically and 20 km–30 km horizontally. Finally, a comparison of the 3-D inversion with conventional 1-D inversions using the assumption of a horizontally homogeneous atmosphere is performed.
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- 2018
207. NMR analyses of complex d-glucose anomerization
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Lothar W. Kroh, Clemens Mügge, and Martin Kaufmann
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chemistry.chemical_classification ,Anomer ,Magnetic Resonance Spectroscopy ,010405 organic chemistry ,Thermodynamic equilibrium ,Temperature ,General Medicine ,Nuclear magnetic resonance spectroscopy ,010402 general chemistry ,Furanose ,01 natural sciences ,0104 chemical sciences ,Analytical Chemistry ,Solutions ,Kinetics ,Reaction rate constant ,Glucose ,chemistry ,Pyranose ,Proton NMR ,Physical chemistry ,Thermodynamics ,Reactivity (chemistry) ,Food Science - Abstract
Analyzing the 1H NMR spectrum of d-glucose, the resonance frequencies of the anomeric protons of five d-glucose anomers could be determined in dependence on temperature. Besides, the relative concentrations of all cyclic d-glucose anomers could be quantified. Based on that, thermodynamic parameters were calculated. In addition, ring opening rate constants of all cyclic d-glucose anomers were measured for the first time using 1H selective blind saturation transfer NMR spectroscopy. The results presented here give rise to the assumption that furanoid anomers highly influence the reactivity of total d-glucose. Finally, the complex anomeric equilibration curves for a freshly prepared solution of crystalline α-d-glucopyranose are presented. Based on that, it is hypothesized that the reactivity of a solution of a reducing sugar in general and d-glucose in particular depends on time until the thermodynamic equilibrium state is reached.
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- 2018
208. General acid/base catalysis of sugar anomerization
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Martin Kaufmann, Lothar W. Kroh, Sophie Krüger, and Clemens Mügge
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Magnetic Resonance Spectroscopy ,Carboxylic acid ,Fructose ,010402 general chemistry ,01 natural sciences ,Catalysis ,Analytical Chemistry ,symbols.namesake ,Reaction rate constant ,Organic chemistry ,Reactivity (chemistry) ,Amino Acids ,Sugar ,chemistry.chemical_classification ,010405 organic chemistry ,Cationic polymerization ,General Medicine ,Hydrogen-Ion Concentration ,0104 chemical sciences ,Amino acid ,Maillard Reaction ,Maillard reaction ,chemistry ,symbols ,Thermodynamics ,Sugars ,Food Science - Abstract
Based on theoretical and mechanistical considerations, an equation is presented that describes the observed rate of a pH sensitive reaction. In contrast to the commonly used catalytic catenary, the new approach enables the calculation of non-biased thermodynamic activation parameters. Applying this model, the general acid/base catalysis of the ring opening of β-d-fructopyranose was analyzed polarimetrically. Thereby, it could be shown that acids (bases) catalyze the ring opening of anionic (cationic) sugar species. Since anomerization rate constants correlate with the rate of sugar degradation, catalysts of anomerization will increase the sugar's reactivity as well. The most effective catalysts of the ring opening of β-d-fructopyranose in the food relevant pH milieu are weak acids and their conjugated bases. Consequently, the enhanced reactivity of reducing sugars in the presence of amino acids is not solely due to classical Maillard reaction but primarily due to carboxylic acid catalysis of degradation reactions.
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- 2018
209. A Miniaturized Limb Sounder Utilizing a Spatial Heterodyne Spectrometer for the Observation of the Molecular Oxygen Atmospheric Band
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Klaus Mantel, Gordon G. Shepherd, Oliver Wroblowski, Ralf Koppmann, Denis Fröhlich, Martin Riese, Michael Deiml, Geshi Tang, Jinjun Shan, Jilin Liu, Brian Solheim, Tom Neubert, Martin Kaufmann, Friedhelm Olschewski, Heinz Rongen, and Qiuyu Chen
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Atmosphere ,Heterodyne ,Materials science ,Optics ,Spectrometer ,business.industry ,Detector ,Measure (physics) ,Molecular oxygen ,business - Abstract
A CubeSat-sized limb sounder utilizing a Spatial Heterodyne Spectrometer for the detection of the O2 Atmospheric A-Band is presented. The purpose of the instrument is to measure vertical profiles of temperature in the middle atmosphere.
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- 2018
210. MIPAS observations of ozone in the middle atmosphere
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Norbert Glatthor, Kaley A. Walker, Thomas von Clarmann, Lucien Froidevaux, Viktoria Sofieva, Maya García-Comas, Masato Shiotani, Martin Kaufmann, Manuel López-Puertas, A. Laeng, Bernd Funke, Angela Gardini, Gabriele Stiller, Ministerio de Ciencia e Innovación (España), European Commission, European Space Agency, Ministerio de Economía y Competitividad (España), and Canadian Space Agency
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Atmospheric Science ,Daytime ,010504 meteorology & atmospheric sciences ,lcsh:TA715-787 ,Diurnal temperature variation ,lcsh:Earthwork. Foundations ,Atmospheric sciences ,01 natural sciences ,Latitude ,Mesosphere ,lcsh:Environmental engineering ,010309 optics ,Atmosphere ,Earth sciences ,Altitude ,0103 physical sciences ,ddc:550 ,Environmental science ,Spectral resolution ,Thermosphere ,lcsh:TA170-171 ,0105 earth and related environmental sciences - Abstract
This work is distributed under the Creative Commons Attribution 4.0 License., In this paper we describe the stratospheric and mesospheric ozone (version V5r-O3-m22) distributions retrieved from MIPAS observations in the three middle atmosphere modes (MA, NLC, and UA) taken with an unapodized spectral resolution of 0.0625 cm from 2005 until April 2012. O is retrieved from microwindows in the 14.8 and 10 μm spectral regions and requires non-local thermodynamic equilibrium (non-LTE) modelling of the O and vibrational levels. Ozone is reliably retrieved from 20 km in the MA mode (40 km for UA and NLC) up to ∼105 km during dark conditions and up to ∼95 km during illuminated conditions. Daytime MIPAS O has an average vertical resolution of 3-4 km below 70 km, 6-8 km at 70-80 km, 8-10 km at 80-90, and 5-7 km at the secondary maximum (90-100 km). For nighttime conditions, the vertical resolution is similar below 70 km and better in the upper mesosphere and lower thermosphere: 4-6 km at 70-100 km, 4-5 km at the secondary maximum, and 6-8 km at 100-105 km. The noise error for daytime conditions is typically smaller than 2% below 50 km, 2-10% between 50 and 70 km, 10-20% at 70-90 km, and ∼30% above 95 km. For nighttime, the noise errors are very similar below around 70 km but significantly smaller above, being 10-20% at 75-95 km, 20-30% at 95-100 km, and larger than 30% above 100 km. The additional major O errors are the spectroscopic data uncertainties below 50 km (10-12 %) and the non-LTE and temperature errors above 70 km. The validation performed suggests that the spectroscopic errors below 50 km, mainly caused by the O air-broadened half-widths of the band, are overestimated. The non-LTE error (including the uncertainty of atomic oxygen in nighttime) is relevant only above ∼85 km with values of 15-20 %. The temperature error varies from ∼3% up to 80 km to 15-20% near 100 km. Between 50 and 70 km, the pointing and spectroscopic errors are the dominant uncertainties. The validation performed in comparisons with SABER, GOMOS, MLS, SMILES, and ACE-FTS shows that MIPAS O has an accuracy better than 5% at and below 50 km, with a positive bias of a few percent. In the 50-75 km region, MIPAS O has a positive bias of ∼10 %, which is possibly caused in part by O spectroscopic errors in the 10 μm region. Between 75 and 90 km, MIPAS nighttime O is in agreement with other instruments by 10 %, but for daytime the agreement is slightly larger, ∼10-20 %. Above 90 km, MIPAS daytime O is in agreement with other instruments by 10 %. At night, however, it shows a positive bias increasing from 10% at 90 km to 20% at 95-100 km, the latter of which is attributed to the large atomic oxygen abundance used. We also present MIPAS O distributions as function of altitude, latitude, and time, showing the major O features in the middle and upper mesosphere. In addition to the rapid diurnal variation due to photochemistry, the data also show apparent signatures of the diurnal migrating tide during both day-and nighttime, as well as the effects of the semi-Annual oscillation above ∼70 km in the tropics and mid-latitudes. The tropical. daytime O at 90 km shows a solar signature in phase with the solar cycle. © Author(s) 2018., The IAA team was supported by the Spanish MICINN under the project ESP2014-54362-P and EC FEDER funds. The IAA and IMK teams were partially supported by ESA O3-CCI and MesosphEO projects. Maya Garcia-Comas was financially supported by MINECO through its >Ramon y Cajal> subprogram. Funding for the Atmospheric Chemistry Experiment comes primarily from the Canadian Space Agency. Work at the Jet Propulsion Laboratory was performed under contract with the National Aeronautics and Space Administration.
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- 2018
211. List of Contributors
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John S. Adams, Judith E. Adams, Jawaher A. Alsalem, Paul H. Anderson, Panagiota Andreopoulou, Edith Angellotti, Leggy A. Arnold, Gerald J. Atkins, Antonio Barbáchano, Shari S. Bassuk, Sarah Beaudin, Anna Y. Belorusova, Nancy A. Benkusky, Carlos Bernal-Mizrachi, Ishir Bhan, Harjit P. Bhattoa, Daniel D. Bikle, John P. Bilezikian, Neil C. Binkley, Heike A. Bischoff-Ferrari, Charles W. Bishop, Ida M. Boisen, Fabrizio Bonelli, Adele L. Boskey, Barbara J. Boucher, Roger Bouillon, Manuella Bouttier, Barbara D. Boyan, Danny Bruce, Laura Buburuzan, Andrew J. Burghardt, Thomas H.J. Burne, Mona S. Calvo, Carlos A. Camargo, Jorge B. Cannata-Andia, Margherita T. Cantorna, Carsten Carlberg, Geert Carmeliet, Thomas O. Carpenter, Graham D. Carter, Kevin D. Cashman, Lisa Ceglia, Sylvia Christakos, Kenneth B. Christopher, Rene F. Chun, Fredric L. Coe, Frederick Coffman, Juliet Compston, Cyrus Cooper, Elizabeth M. Curtis, Natalie E. Cusano, Michael Danilenko, G. David Roodman, Bess Dawson-Hughes, Pierre De Clercq, Hector F. DeLuca, Julie Demaret, Marie B. Demay, David W. Dempster, Elaine M. Dennison, Puneet Dhawan, Vassil Dimitrov, Katie M. Dixon, Maryam Doroudi, Shevaun M. Doyle, Adriana S. Dusso, Aleksey Dvorzhinskiy, Peter R. Ebeling, John A. Eisman, Gregory R. Emkey, Ervin H. Epstein Jr., Sol Epstein, Darryl Eyles, Murray J. Favus, David Feldman, Gemma Ferrer-Mayorga, David M. Findlay, James C. Fleet, Brian L. Foster, Renny T. Franceschi, David R. Fraser, Jessica M. Furst, Rachel I. Gafni, Edward Giovannucci, Christian M. Girgis, James L. Gleason, Francis H. Glorieux, Elzbieta Gocek, David Goltzman, José Manuel González-Sancho, Laura A. Graeff-Armas, William B. Grant, Natalie J. Groves, Conny Gysemans, Lasse Bøllehuus Hansen, Nicholas C. Harvey, Catherine M. Hawrylowicz, Colleen E. Hayes, Robert P. Heaney, Geoffrey N. Hendy, Pamela A. Hershberger, Martin Hewison, Michael F. Holick, Bruce W. Hollis, Philippe P. Hujoel, Elina Hyppönen, Karl L. Insogna, Nina G. Jablonski, Martin Blomberg Jensen, David A. Jolliffe, Glenville Jones, Kerry S. Jones, Harald Jüppner, Enikö Kallay, Andrew C. Karaplis, Martin Kaufmann, Mairead Kiely, Tiffany Y, Kim, Martin Konrad, Christopher S. Kovacs, Richard Kremer, Roland Krug, Rajiv Kumar, Noriyoshi Kurihara, Emma Laing, Joseph M. Lane, Dean P. Larner, María Jesús Larriba, Gilles Laverny, Nathalie Le Roy, Seong M. Lee, Michael A. Levine, Richard Lewis, Paul Lips, Thomas S. Lisse, Eva S. Liu, Philip T. Liu, Yan Li, Yan Chun Li, James G. MacKrell, Leila J. Mady, Sharmila Majumdar, Makoto Makishima, Peter J. Malloy, Elizabeth H. Mann, JoAnn E. Manson, Adrian R. Martineau, Rebecca S. Mason, Chantal Mathieu, Toshio Matsumoto, Donald G. Matthews, John J. McGrath, Daniel Metzger, Mark B. Meyer, Denshun Miao, Mathew T. Mizwicki, Rebecca J. Moon, Howard A. Morris, Li J. Mortensen, Alberto Muñoz, Yuko Nakamichi, Carmen J. Narvaez, Faye E. Nashold, Tally Naveh-Many, Carrie M. Nielson, Anthony W. Norman, Yves Nys, Melda Onal, Lubna Pal, Kristine Y. Patterson, Steven Pauwels, Pamela R. Pehrsson, Martin Petkovich, John M. Pettifor, Paul E. Pfeffer, Katherine M. Phillips, J. Wesley Pike, Stefan Pilz, Anastassios G. Pittas, Pawel Pludowski, David E. Prosser, Sri Ramulu N. Pullagura, L. Darryl Quarles, Rithwick Rajagopal, Katherine J. Ransohoff, Saaeha Rauz, Brian J. Rebolledo, Jörg Reichrath, Sandra Rieger, Amy E. Riek, Natacha Rochel, Jeffrey D. Roizen, Janet M. Roseland, Cliff Rosen, Mark S. Rybchyn, Hiroshi Saitoh, Reyhaneh Salehi-Tabar, Anne L. Schafer, Karl P. Schlingmann, Inez Schoenmakers, Zvi Schwartz, Kayla Scott, Christopher T. Sempos, Lusia Sepiashvili, Mukund Seshadri, Elizabeth Shane, Tatiana Shaurova, Irene Shui, Justin Silver, Ravinder J. Singh, Linda Skingle, René St-Arnaud, Jessica Starr, Keith R. Stayrook, Emily M. Stein, Ryan E. Stites, George P. Studzinski, Tatsuo Suda, Fumiaki Takahashi, Naoyuki Takahashi, Jean Y. Tang, Christine L. Taylor, Hugh S. Taylor, Peter J. Tebben, Thomas D. Thacher, Ravi Thadhani, Kebashni Thandrayen, Susan Thys-Jacobs, Dov Tiosano, Roberto Toni, Dwight A. Towler, Donald L. Trump, Nobuyuki Udagawa, André G. Uitterlinden, Aasis Unnanuntana, Jeroen van de Peppel, Bram C.J. van der Eerden, Marjolein van Driel, Johannes P.T.M. van Leeuwen, Natasja van Schoor, An-Sofie Vanherwegen, Aria Vazirnia, Lieve Verlinden, Annemieke Verstuyf, Reinhold Vieth, Carol L. Wagner, Graham R. Wallace, Connie Weaver, JoEllen Welsh, John H. White, Susan J. Whiting, Michael P. Whyte, John J. Wysolmerski, Sachiko Yamada, Olivia B. Yu, Kathryn Zavala, Christoph Zechner, Meltem Zeytinoglu, and Hengguang Zhao
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- 2018
212. Mass Spectrometry Assays of Vitamin D Metabolites
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Martin Kaufmann, Lusia Sepiashvili, and Ravinder J. Singh
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Vitamin ,chemistry.chemical_compound ,Chromatography ,Vitamin D+Metabolites ,Vitamin D metabolism ,chemistry ,Liquid chromatography–mass spectrometry ,Basic research ,Vitamin D and neurology ,Derivatization ,Mass spectrometry - Abstract
Liquid chromatography tandem mass spectrometry (LC-MS/MS) has emerged as the gold standard technique with the capability for reliable, accurate, and high-throughput quantification of circulating vitamin D metabolites. The complexity of vitamin D metabolism has driven the continuous development of the basic steps involved in LC-MS/MS methodology including sample extraction, derivatization, separation, and mass spectrometry, used to interrogate the role of vitamin D nutrition and metabolism in human health and disease states. From the perspective of both the high-throughput clinical chemistry laboratory and basic research applications, this chapter describes how LC-MS/MS can be optimized to provide sensitive and specific measurements of 25-hydroxyvitamin D, along with other low-abundance metabolites including 24-25-dihydroxyvitamin D and 1,25-dihydroxyvitamin D, simultaneously. Furthermore, we describe the advantages of using LC-MS/MS in studying mouse models of vitamin D metabolism and how this work has contributed to an improved understanding of the pathophysiology of certain vitamin D-related disease states.
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- 2018
213. The Activating Enzymes of Vitamin D Metabolism (25- and 1α-Hydroxylases)
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Glenville Jones, David E. Prosser, and Martin Kaufmann
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0301 basic medicine ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,030209 endocrinology & metabolism - Published
- 2018
214. Simultaneous formation of 3-deoxy-d-threo-hexo-2-ulose and 3-deoxy-d-erythro-hexo-2-ulose during the degradation of d-glucose derived Amadori rearrangement products: Mechanistic considerations
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Clemens Mügge, Sophie Krüger, Martin Kaufmann, and Lothar W. Kroh
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Magnetic Resonance Spectroscopy ,Stereochemistry ,Substituent ,Protonation ,010402 general chemistry ,01 natural sciences ,Biochemistry ,Analytical Chemistry ,chemistry.chemical_compound ,Deprotonation ,D-Glucose ,Amadori rearrangement ,Ketoses ,Amino Acids ,chemistry.chemical_classification ,010405 organic chemistry ,Hydrogen bond ,Organic Chemistry ,Galactose ,General Medicine ,Nuclear magnetic resonance spectroscopy ,0104 chemical sciences ,Amino acid ,Maillard Reaction ,Glucose ,chemistry - Abstract
Analyzing classical model reaction systems of Amadori rearrangement products (ARP) it became apparent that the formation of 3-deoxy- d -threo-hexo-2-ulose (3-deoxygalactosone, 3-DGal) during the degradation of ARPs is highly dependent on pH and the amino acid residue of the respective ARP. Based on a detailed analysis of the NMR chemical shifts of the sugar moieties of different ARPs, it could be derived that the formation of 3-DGal is sensitive to the stability of a co-operative hydrogen bond network which involves HO-C3, the deprotonated carboxyl functionality and the protonated amino nitrogen of the amino acid substituent. Participating in this bond network, HO-C3 is partially protonated which facilitates the elimination of water at C3. Based on that, a new mechanism of 3-deoxyglycosone formation is proposed.
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- 2017
215. On the Control of Chromophore Orientation, Supramolecular Structure, and Thermodynamic Stability of an Amphiphilic Pyridyl-Thiazol upon Lateral Compression and Spacer Length Variation
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Felix Herrmann-Westendorf, Volker Deckert, Martin Kaufmann, Dieter Weiß, Karl-Heinz Feller, Ludovic Roussille, Rainer Beckert, Benjamin Dietzek, Torsten Sachse, Maximilian L. Hupfer, and Martin Presselt
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Materials science ,Supramolecular chemistry ,02 engineering and technology ,Chromophore ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Fluorescence ,Langmuir–Blodgett film ,0104 chemical sciences ,Crystallography ,chemistry.chemical_compound ,chemistry ,Amphiphile ,Molecule ,General Materials Science ,Chemical stability ,0210 nano-technology ,Thiazole - Abstract
The supramolecular structure essentially determines the properties of organic thin films. Therefore, it is of utmost importance to understand the influence of molecular structure modifications on supramolecular structure formation. In this article, we demonstrate how to tune molecular orientations of amphiphilic 4-hydroxy thiazole derivatives by means of the Langmuir-Blodgett (LB) technique and how this depends on the length of an alkylic spacer between the thiazole chromophore and the polar anchor group. Therefore, we characterize their corresponding supramolecular structures, thermodynamic, absorption, and fluorescence properties. Particularly, the polarization-dependence of the fluorescence is analyzed to deduce molecular orientations and their possible changes after annealing, i.e., to characterize the thermodynamic stability of the individual solid state phases. Because the investigated thiazoles are amphiphilic, the different solid state phases can be formed and be controlled by means of the Langmuir-Blodgett (LB) technique. This technique also allows to deduce atomistic supramolecular structure motives of the individual solid phases and to characterize their thermodynamic stabilities. Utilizing the LB technique, we demonstrate that subtle molecular changes, like the variation in spacer length, can yield entirely different solid state phases with distinct supramolecular structures and properties.
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- 2017
216. Nighttime atomic oxygen in the mesopause region retrieved from SCIAMACHY O(1S) green line measurements and its response to solar cycle variation
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Martin Kaufmann, Martin Riese, Manfred Ern, and Yajun Zhu
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Atmospheric sciences ,SCIAMACHY ,Solar cycle ,Mesosphere ,Atmosphere ,Depth sounding ,Geophysics ,Space and Planetary Science ,Physics::Space Physics ,Mesopause ,Environmental science ,Radiometry ,Astrophysics::Earth and Planetary Astrophysics ,Thermosphere ,Remote sensing - Abstract
This paper presents new data sets relating to the abundance of atomic oxygen in the upper mesosphere and lower thermosphere, which were derived from the nighttime green line emission measurements of the SCIAMACHY (Scanning Imaging Absorption Spectrometer for Atmospheric CHartographY) instrument on the European Environmental Satellite (Envisat). These are compared to recently published data sets from the same SCIAMACHY green line measurements through the application of a different photochemical model and to data collected by the Sounding of the Atmosphere using Broadband Emission Radiometry instrument. We find that the retrieved atomic oxygen concentration depends on the choice of the underlying photochemical model. These dependencies explain a large proportion of the differences between recently published data sets. The impact of the 11 year solar cycle on volume emission rates and atomic oxygen abundances was analyzed for various data sets, with the finding that the solar cycle effect varies with the atomic oxygen data set used. The solar cycle impact on the SCIAMACHY data increases with altitude. Above 96 km, it is significantly larger than predicted by Hamburg Model of the Neutral and Ionized Atmosphere. Investigations indicate that these variations are primarily driven by total density compression/expansion variations during the solar cycle, rather than different photolysis rates.
- Published
- 2015
217. Maternal Hypercalcemia Due to Failure of 1,25-Dihydroxyvitamin-D3Catabolism in a Patient WithCYP24A1Mutations
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Kirsten Salmeen, Martin Kaufmann, Arti D. Shah, Betsy O'Donnell, Robert L. Nussbaum, Daniel D. Bikle, Michael Krebs, Sabina Baumgartner-Parzer, Yongmei Wang, Edward C. Hsiao, Glenville Jones, Dolores M. Shoback, Ingrid Block-Kurbisch, and Allen S. Mathew
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Adult ,medicine.medical_specialty ,Endocrinology, Diabetes and Metabolism ,Clinical Biochemistry ,Context (language use) ,Nephrolithiasis ,Biochemistry ,chemistry.chemical_compound ,Endocrinology ,CYP24A1 ,Pregnancy ,Internal medicine ,medicine ,Vitamin D and neurology ,Humans ,Hypercalciuria ,Vitamin D ,Vitamin D3 24-Hydroxylase ,Calcium metabolism ,Fetus ,business.industry ,Biochemistry (medical) ,Special Features ,medicine.disease ,Pregnancy Complications ,chemistry ,Mutation ,Hypercalcemia ,Female ,Calcifediol ,business ,Metabolic Networks and Pathways - Abstract
Calcium metabolism changes in pregnancy and lactation to meet fetal needs, with increases in 1,25-dihydroxyvitamin D [1,25-(OH)2D] during pregnancy playing an important role. However, these changes rarely cause maternal hypercalcemia. When maternal hypercalcemia occurs, further investigation is essential, and disorders of 1,25-(OH)2D catabolism should be carefully considered in the differential diagnosis.A patient with a childhood history of recurrent renal stone disease and hypercalciuria presented with recurrent hypercalcemia and elevated 1,25-(OH)2D levels during pregnancy. Laboratory tests in the fourth pregnancy showed suppressed PTH, elevated 1,25-(OH)2D, and high-normal 25-hydroxyvitamin D levels, suggesting disordered vitamin D metabolism. Analysis revealed low 24,25-dihydroxyvitamin D3 and high 25-hydroxyvitamin D3 levels, suggesting loss of function of CYP24A1 (25-hydroxyvitamin-D3-24-hydroxylase). Gene sequencing confirmed that she was a compound heterozygote with the E143del and R396W mutations in CYP24A1.This case broadens presentations of CYP24A1 mutations and hypercalcemia in pregnancy. Furthermore, it illustrates that patients with CYP24A1 mutations can maintain normal calcium levels during the steady state but can develop hypercalcemia when challenged, such as in pregnancy when 1,25-(OH)2D levels are physiologically elevated.
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- 2015
218. Retrieval of three-dimensional small-scale structures in upper-tropospheric/lower-stratospheric composition as measured by GLORIA
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Erik Kretschmer, Hermann Oelhaf, Hans Schlager, Fred Stroh, Peter Preusse, Herbert Schneider, Dirk Schuettemeyer, Johannes Orphal, Wolfgang Woiwode, Felix Friedl-Vallon, Martin Riese, Friedhelm Olschewski, Bärbel Vogel, H. Nordmeyer, Michael Höpfner, D. Gerber, G. Guenther, Tom Neubert, O. Suminska-Ebersoldt, Guido Maucher, C. M. Volk, Jörn Ungermann, Th. Latzko, J. Blank, T. Guggenmoser, Jens-Uwe Grooß, Anne Kleinert, Andreas Engel, Manfred Ern, and Martin Kaufmann
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Atmospheric Science ,Meteorology ,lcsh:TA715-787 ,lcsh:Earthwork. Foundations ,lcsh:Environmental engineering ,Upper tropospher ,Atmosphere ,Troposphere ,Earth sciences ,lower stratosphere ,transport ,ddc:550 ,Radiance ,Earth system model ,lcsh:TA170-171 ,Focus (optics) ,Scale (map) ,Stratosphere ,Image resolution ,Geology ,Remote sensing - Abstract
The three-dimensional quantification of small-scale processes in the upper troposphere and lower stratosphere is one of the challenges of current atmospheric research and requires the development of new measurement strategies. This work presents the first results from the newly developed Gimballed Limb Observer for Radiance Imaging of the Atmosphere (GLORIA) obtained during the ESSenCe (ESa Sounder Campaign) and TACTS/ESMVal (TACTS: Transport and composition in the upper troposphere/lowermost stratosphere, ESMVal: Earth System Model Validation) aircraft campaigns. The focus of this work is on the so-called dynamics-mode data characterized by a medium-spectral and a very-high-spatial resolution. The retrieval strategy for the derivation of two- and three-dimensional constituent fields in the upper troposphere and lower stratosphere is presented. Uncertainties of the main retrieval targets (temperature, O3, HNO3, and CFC-12) and their spatial resolution are discussed. During ESSenCe, high-resolution two-dimensional cross-sections have been obtained. Comparisons to collocated remote-sensing and in situ data indicate a good agreement between the data sets. During TACTS/ESMVal, a tomographic flight pattern to sense an intrusion of stratospheric air deep into the troposphere was performed. It was possible to reconstruct this filament at an unprecedented spatial resolution of better than 500 m vertically and 20 × 20 km horizontally.
- Published
- 2015
219. A kidney-specific genetic control module in mice governs endocrine regulation of the cytochrome P450 gene Cyp27b1 essential for vitamin D3 activation
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Glenville Jones, Seong Min Lee, Martin Kaufmann, Melda Onal, Nancy A. Benkusky, Mark B. Meyer, and J. Wesley Pike
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0301 basic medicine ,Fibroblast growth factor 23 ,medicine.medical_specialty ,25-Hydroxyvitamin D3 1-alpha-hydroxylase ,Parathyroid hormone ,030209 endocrinology & metabolism ,Vitamin D3 24-Hydroxylase ,Biology ,Kidney ,Biochemistry ,Calcitriol receptor ,Gene Expression Regulation, Enzymologic ,03 medical and health sciences ,chemistry.chemical_compound ,Mice ,0302 clinical medicine ,CYP24A1 ,Calcitriol ,Internal medicine ,medicine ,Animals ,Homeostasis ,Editors' Picks ,Molecular Biology ,Cholecalciferol ,Regulation of gene expression ,25-Hydroxyvitamin D3 1-alpha-Hydroxylase ,Cell Biology ,Fibroblast Growth Factor-23 ,030104 developmental biology ,Endocrinology ,chemistry ,Organ Specificity ,Gene Deletion - Abstract
The vitamin D endocrine system regulates mineral homeostasis through its activities in the intestine, kidney, and bone. Terminal activation of vitamin D3 to its hormonal form, 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3), occurs in the kidney via the cytochrome P450 enzyme CYP27B1. Despite its importance in vitamin D metabolism, the molecular mechanisms underlying the regulation of the gene for this enzyme, Cyp27b1, are unknown. Here, we identified a kidney-specific control module governed by a renal cell-specific chromatin structure located distal to Cyp27b1 that mediates unique basal and parathyroid hormone (PTH)-, fibroblast growth factor 23 (FGF23)-, and 1,25(OH)2D3-mediated regulation of Cyp27b1 expression. Selective genomic deletion of key components within this module in mice resulted in loss of either PTH induction or FGF23 and 1,25(OH)2D3 suppression of Cyp27b1 gene expression; the former loss caused a debilitating skeletal phenotype, whereas the latter conferred a quasi-normal bone mineral phenotype through compensatory homeostatic mechanisms involving Cyp24a1. We found that Cyp27b1 is also expressed at low levels in non-renal cells, in which transcription was modulated exclusively by inflammatory factors via a process that was unaffected by deletion of the kidney-specific module. These results reveal that differential regulation of Cyp27b1 expression represents a mechanism whereby 1,25(OH)2D3 can fulfill separate functional roles, first in the kidney to control mineral homeostasis and second in extra-renal cells to regulate target genes linked to specific biological responses. Furthermore, we conclude that these mouse models open new avenues for the study of vitamin D metabolism and its involvement in therapeutic strategies for human health and disease.
- Published
- 2017
220. Interlaboratory Comparison for the Determination of 24,25-Dihydroxyvitamin D₃ in Human Serum Using Liquid Chromatography with Tandem Mass Spectrometry
- Author
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Stephen A, Wise, Susan S-C, Tai, Michael A, Nelson, Carolyn Q, Burdette, Johanna E, Camara, Andrew N, Hoofnagle, Thomas J, Laha, Graham D, Carter, Julia, Jones, Emma L, Williams, Zoe J, Barclay, Glenville, Jones, Martin, Kaufmann, Neil, Binkley, Amita, Kapoor, Toni, Ziegler, Kevin D, Cashman, Kirsten G, Dowling, and Christopher T, Sempos
- Subjects
Laboratory Proficiency Testing ,24,25-Dihydroxyvitamin D 3 ,Tandem Mass Spectrometry ,Humans ,Reference Standards ,Vitamin D ,Blood Chemical Analysis ,Chromatography, Liquid - Abstract
Six laboratories associated with the Vitamin D Standardization Program (VDSP) participated in an interlaboratory comparison of LC with tandem MS (MS/MS) methods for the determination of 24,25-dihydroxyvitamin D3 [24,25(OH)2D3] in human serum. The laboratories analyzed two different serum-based Standard Reference Materials (SRMs) intended for use in the determination of 25-hydroxyvitamin D and 30 samples from the Vitamin D External Quality Assessment Scheme (DEQAS). All laboratory methods for 24,25(OH)2D3 were based on isotope dilution LC-MS/MS; three of the methods used derivatization of the vitamin D metabolites before LC-MS/MS. Laboratory results were compared to the National Institute of Standards and Technology (NIST) results, which were obtained using their newly developed candidate reference measurement procedure for 24,25(OH)2D3. Laboratory results for the SRM samples varied in comparability to the NIST results, with one laboratory in excellent agreement (-1.6% mean bias), three laboratories at 10-15% mean bias, and the remaining laboratory at 36% mean bias. For the 30 DEQAS samples, the mean bias for the five laboratories ranged from 6 to 15%; however, the SD of the bias ranged from 8 to 29%. As a result of this intercomparison study, one laboratory discovered and corrected a method calculation error and another laboratory modified and improved their LC-MS/MS method.
- Published
- 2017
221. Supplementary material to 'First tomographic observations of gravity waves by the infrared limb imager GLORIA'
- Author
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Isabell Krisch, Peter Preusse, Jörn Ungermann, Andreas Dörnbrack, Stephen D. Eckermann, Manfred Ern, Felix Friedl-Vallon, Martin Kaufmann, Hermann Oelhaf, Markus Rapp, Cornelia Strube, and Martin Riese
- Published
- 2017
222. The Viral Gene ORF79 Encodes a Repressor Regulating Induction of the Lytic Life Cycle in the Haloalkaliphilic Virus ϕCh1
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Reinhard Klein, Beatrix Alte, Christian Derntl, Lea Schöner, Martin Kaufmann, Angela Witte, Judith Beraha, Christoph Hofbauer, and Regina Selb
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0301 basic medicine ,Genes, Viral ,viruses ,030106 microbiology ,Immunology ,Mutant ,Repressor ,Biology ,Microbiology ,Virus ,Open Reading Frames ,Viral Proteins ,03 medical and health sciences ,Virology ,Lysogenic cycle ,Promoter Regions, Genetic ,Lysogeny ,Gene ,Genetics ,Halobacteriaceae ,Provirus ,Reverse genetics ,Virus-Cell Interactions ,Repressor Proteins ,030104 developmental biology ,Lytic cycle ,Myoviridae ,Insect Science ,DNA, Viral ,Virus Physiological Phenomena - Abstract
In this study, we describe the construction of the first genetically modified mutant of a halovirus infecting haloalkaliphilic Archaea . By random choice, we targeted ORF79, a currently uncharacterized viral gene of the haloalkaliphilic virus ϕCh1. We used a polyethylene glycol (PEG)-mediated transformation method to deliver a disruption cassette into a lysogenic strain of the haloalkaliphilic archaeon Natrialba magadii bearing ϕCh1 as a provirus. This approach yielded mutant virus particles carrying a disrupted version of ORF79. Disruption of ORF79 did not influence morphology of the mature virions. The mutant virus was able to infect cured strains of N. magadii , resulting in a lysogenic, ORF79-disrupted strain. Analysis of this strain carrying the mutant virus revealed a repressor function of ORF79. In the absence of gp79, onset of lysis and expression of viral proteins occurred prematurely compared to their timing in the wild-type strain. Constitutive expression of ORF79 in a cured strain of N. magadii reduced the plating efficiency of ϕCh1 by seven orders of magnitude. Overexpression of ORF79 in a lysogenic strain of N. magadii resulted in an inhibition of lysis and total absence of viral proteins as well as viral progeny. In further experiments, gp79 directly regulated the expression of the tail fiber protein ORF34 but did not influence the methyltransferase gene ORF94. Further, we describe the establishment of an inducible promoter for in vivo studies in N. magadii . IMPORTANCE Genetic analyses of haloalkaliphilic Archaea or haloviruses are only rarely reported. Therefore, only little insight into the in vivo roles of proteins and their functions has been gained so far. We used a reverse genetics approach to identify the function of a yet undescribed gene of ϕCh1. We provide evidence that gp79, a currently unknown protein of ϕCh1, acts as a repressor protein of the viral life cycle, affecting the transition from the lysogenic to the lytic state of the virus. Thus, repressor genes in other haloviruses could be identified by sequence homologies to gp79 in the future. Moreover, we describe the use of an inducible promoter of N. magadii . Our work provides valuable tools for the identification of other unknown viral genes by our approach as well as for functional studies of proteins by inducible expression.
- Published
- 2017
223. Validation of a routine two-sample iohexol plasma clearance assessment of GFR and an evaluation of common endogenous markers in a rat model of CKD
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Mandy E Turner, Michael A. Adams, Christine A. White, Martin Kaufmann, Glenville Jones, Paul S Jeronimo, Rachel M. Holden, and Kimberly Laverty
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Male ,medicine.medical_specialty ,Physiology ,Metabolic Clearance Rate ,Iohexol ,Inulin ,Urology ,Renal function ,Contrast Media ,Endogeny ,030204 cardiovascular system & hematology ,Kidney ,GFR ,030218 nuclear medicine & medical imaging ,Rats, Sprague-Dawley ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Physiology (medical) ,Internal medicine ,Medicine ,Animals ,Renal Filtration ,Renal Insufficiency, Chronic ,plasma clearance ,Original Research ,Creatinine ,Plasma clearance ,inulin ,business.industry ,Renal Conditions, Disorders and Treatments ,Rats ,Renal Elimination ,Endocrinology ,chemistry ,Animal studies ,business ,Biomarkers ,medicine.drug ,Glomerular Filtration Rate - Abstract
Endogenous markers of kidney function are insensitive to early declines in glomerular filtration rate (GFR) and in rodent models, validated, practical alternatives are unavailable. In this study, we determined GFR by modeling the plasma clearance of two compounds, iohexol and inulin, and compared the findings to common endogenous markers. All plasma clearance methods of both iohexol and inulin detected a decline in renal function weeks prior to any increase in endogenous marker. Iohexol plasma clearance and inulin plasma clearance had a very high agreement and minimal bias when using 12‐sample models. However, only iohexol could be accurately simplified to a two‐sample, one‐compartment estimation strategy. Following an IV injection of low‐dose iohexol and two timed blood samples at 30 and 90 min, one can accurately approximate a complex 12‐sample strategy of plasma clearance. This method is simple enough to use in routine, longitudinal analysis of larger cohort animal studies.
- Published
- 2017
224. First tomographic observations of gravity waves by the infrared limb imager GLORIA
- Author
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Isabell Krisch, Peter Preusse, Jörn Ungermann, Andreas Dörnbrack, Stephen D. Eckermann, Manfred Ern, Felix Friedl-Vallon, Martin Kaufmann, Hermann Oelhaf, Markus Rapp, Cornelia Strube, and Martin Riese
- Subjects
Earth sciences ,3-D characterization GLORIA ,Institut für Physik der Atmosphäre ,Verkehrsmeteorologie ,ddc:550 ,Atmospheric gravity waves ,Physics::Atmospheric and Oceanic Physics - Abstract
Atmospheric gravity waves are a major cause of uncertainty in atmosphere general circulation models. This uncertainty affects regional climate projections and seasonal weather predictions. Improving the representation of gravity waves in general circulation models is therefore of primary interest. In this regard, measurements providing an accurate 3-D characterization of gravity waves are needed. Using the Gimballed Limb Observer for Radiance Imaging of the Atmosphere (GLORIA), the first airborne implementation of a novel infrared limb imaging technique, a gravity wave event over Iceland was observed. An air volume disturbed by this gravity wave was investigated from different angles by encircling the volume with a closed flight pattern. Using a tomographic retrieval approach, the measurements of this air mass at different angles allowed for a 3-D reconstruction of the temperature and trace gas structure. The temperature measurements were used to derive gravity wave amplitudes, 3-D wave vectors, and direction-resolved momentum fluxes. These parameters facilitated the backtracing of the waves to their sources on the southern coast of Iceland. Two wave packets are distinguished, one stemming from the main mountain ridge in the south of Iceland and the other from the smaller mountains in the north. The total area-integrated fluxes of these two wave packets are determined. Forward ray tracing reveals that the waves propagate laterally more than 2000 km away from their source region. A comparison of a 3-D ray-tracing version to solely column-based propagation showed that lateral propagation can help the waves to avoid critical layers and propagate to higher altitudes. Thus, the implementation of oblique gravity wave propagation into general circulation models may improve their predictive skills.
- Published
- 2017
225. Tomographic reconstruction of atmospheric gravity wave parameters from airglow observations
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Rui Song, Martin Kaufmann, Jörn Ungermann, Manfred Ern, Guang Liu, and Martin Riese
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ddc:550 - Abstract
Gravity waves (GWs) play an important role in atmospheric dynamics. Especially in the mesosphere and lower thermosphere (MLT) dissipating GWs provide a major contribution to the driving of the global wind system. Therefore global observations of GWs in the MLT region are of particular interest. The small scales of GWs, however, pose a major problem for the observation of GWs from space. We propose a new observation strategy for GWs in the mesopause region by combining limb and sub-limb satellite-borne remote sensing measurements for improving the spatial resolution of temperatures that are retrieved from atmospheric soundings. In our study, we simulate satellite observations of the rotational structure of the O2 A-band nightglow. A key element of the new method is the ability of the instrument or the satellite to operate in so called target mode, i.e. to stare at a particular point in the atmosphere and collect radiances at different viewing angles. These multi-angle measurements of a selected region allow for tomographic reconstruction of a 2-dimensional atmospheric state, in particular of gravity wave structures. As no real data is available, the feasibility of this tomographic retrieval is carried out with simulation data in this work. It shows that one major advantage of this observation strategy is that much smaller scale GWs can be observed. We derive a GW sensitivity function, and it is shown that target mode observations are able to capture GWs with horizontal wavelengths as short as ~ 50 km for a large range of vertical wavelengths. This is far better than the horizontal wavelength limit of 100–200 km obtained for conventional limb sounding.
- Published
- 2017
226. A highly miniaturized satellite payload based on a spatial heterodyne spectrometer for atmospheric temperature measurements in the mesosphere and lower thermosphere
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Martin Kaufmann, Friedhelm Olschewski, Klaus Mantel, Brian Solheim, Gordon Shepherd, Michael Deiml, Jilin Liu, Rui Song, Qiuyu Chen, Oliver Wroblowski, Daikang Wei, Yajun Zhu, Friedrich Wagner, Florian Loosen, Denis Froehlich, Tom Neubert, Heinz Rongen, Peter Knieling, Panos Toumpas, Jinjun Shan, Geshi Tang, Ralf Koppmann, and Martin Riese
- Subjects
ddc:550 - Abstract
A highly miniaturized limb sounder for the observation of the O2 A-Band to derive temperatures in the mesosphere and lower thermosphere is presented. The instrument consists of a monolithic spatial heterodyne spectrometer (SHS), which is able to resolve the rotational structure of the R-branch of that band. The relative intensities of the emission lines follow a Boltzmann distribution and the ratio of the lines can be used to derive the kinetic temperature. The SHS operates at a Littrow wavelength of 761.8 nm and heterodynes a wavelength regime between 761.9 nm and 765.3 nm with a resolving power of about 8000 considering apodization effects. The size of the SHS is 38 × 38 × 27 mm3 and its acceptance angle is ±5°. It has an etendue of 0.014 cm2 sr. Complemented by a front optics with a solid angle of 0.65° and a detector optics, the entire optical system fits into a volume of about 1.5 liters. This allows to fly this instrument on a 3 or 6 unit CubeSat. The vertical field of view of the instrument is about 60 km at the Earth's limb if operated in a typical low Earth orbit. Integration times to obtain an entire altitude profile of nighttime temperatures are in the order of one minute for a vertical resolution of 1.5 km and a random noise level of 1.5 K. Daytime integration times are one order of magnitude shorter. This work presents the design parameters of the optics and a radiometric assessment of the instrument. Furthermore it gives an overview of the required characterization and calibration steps. This includes the characterization of image distortions in the different parts of the optics, flat fielding and the spectral power estimation.
- Published
- 2017
227. Vitamin D status in mothers with pre-eclampsia and their infants: a case-control study from Serbia, a country without a vitamin D fortification policy
- Author
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Hope A. Weiler, Glenville Jones, Marija Djekic-Ivankovic, Vesna Aleksic-Velickovic, Martin Kaufmann, Maria Glibetic, Ljuba M. Mandić, and Jovana Kaludjerovic
- Subjects
Adult ,Pediatrics ,medicine.medical_specialty ,Mothers ,Medicine (miscellaneous) ,030209 endocrinology & metabolism ,Vitamin D status ,Comorbidity ,vitamin D deficiency ,Nutrition Policy ,03 medical and health sciences ,0302 clinical medicine ,Pre-Eclampsia ,Pregnancy ,Prevalence ,medicine ,Vitamin D and neurology ,Humans ,030212 general & internal medicine ,Vitamin D ,LC-MS/MS ,Pre-clampsia ,Prenatal vitamins ,Maternal and cord blood ,Nutrition and Dietetics ,Eclampsia ,business.industry ,Obstetrics ,Food fortification ,Public Health, Environmental and Occupational Health ,Case-control study ,Infant ,Gestational age ,Vitamin D Deficiency ,medicine.disease ,Research Papers ,Case-Control Studies ,Dietary Supplements ,Food, Fortified ,Female ,C3-epi-25-hydroxycholecalciferol ,business ,Serbia - Abstract
ObjectiveThe objective of the present study was to determine if vitamin D intake and status are associated with pre-eclampsia in a country without a vitamin D fortification policy.DesignA case–control study of pregnancies with (case) and without (control) pre-eclampsia was conducted from January to April when UVB is minimal. Maternal and cord blood obtained at delivery were measured for plasma 25-hydroxycholecalciferol (25-OH-D3), 3-epimer of 25-OH-D3(3-epi-25-OH-D3) and 24,25-dihydroxycholecalciferol (24,25-(OH)2D3) by LC–MS/MS and maternal 1,25-dihydroxyvitamin D (1,25-(OH)2D). Differences between groups were tested with ANOVA and Bonferronipost hoctests (PSettingClinical Center of Serbia.SubjectsPregnant women with and without pre-eclampsia (n60) and their infants.ResultsExogenous vitamin D intake (0·95–16·25 µg/d (38–650 IU/d)) was not significantly different between groups. Women with pre-eclampsia delivered infants at an earlier gestational age and had significantly lower mean total plasma 25-hydroxyvitamin D (25-OH-D; case: 11·2 (sd5·1); control: 16·1 (sd5·7) ng/ml;P=0·0006), 25-OH-D3(case: 10·0 (sd4·9); control: 14·2 (sd5·8) ng/ml;P=0·002), 3-epi-25-OH-D3(case: 0·5 (sd0·2); control: 0·7 (sd0·2) ng/ml;P=0·0007) and 1,25-(OH)2D (case: 56·5 (sd26·6); control: 81·0 (sd25·7) pg/ml;P=0·018), while 24,25-(OH)2D3was not different between groups. Infants did not differ in total plasma 25-OH-D, 25-OH-D3, 3-epi-25-OH-D3and 24,25-(OH)2D3, but the mean proportion of 3-epi-25-OH-D3was higher in the infant case group (case: 7·9 (sd1·1); control: 7·0 (sd1·4) % of total 25-OH-D3;P=0·005).ConclusionsA high prevalence of vitamin D deficiency, as defined by plasma 25-OH-D
- Published
- 2017
228. Global distribution of atomic oxygen in the mesopause region as derived from SCIAMACHY O(1 S) green line measurements
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Manfred Ern, Martin Riese, Y. Zhu, and Martin Kaufmann
- Subjects
Atmosphere ,Depth sounding ,Geophysics ,Spectrometer ,Mesopause ,Incoherent scatter ,General Earth and Planetary Sciences ,Environmental science ,Thermosphere ,Atmospheric sciences ,Mesosphere ,SCIAMACHY - Abstract
A new data set of atomic oxygen abundance in the upper mesosphere and lower thermosphere is presented. The data are derived from the nighttime atomic oxygen green line limb emission measurements of the SCIAMACHY (Scanning Imaging Absorption Spectrometer for Atmospheric Chartography) instrument on the European Environmental Satellite. The temporal coverage is October 2002 until April 2012, and the latitudinal extent is 50°S to 80°N at 10 P.M. local time. This data set is compared to other satellite data sets, in particular to recently published data of SABER (Sounding of the Atmosphere using Broadband Emission Radiometry) and the Mass Spectrometer and Incoherent Scatter model. SCIAMACHY atomic oxygen peak abundances are typically 3–6×1011 mol/cm3 at the atomic oxygen maximum region, depending on latitude and season. These values are similar to previous values based on chemiluminescence measurements of the atomic oxygen three-body recombination reaction but at least 30% lower than atomic oxygen abundances obtained from SABER.
- Published
- 2014
229. The New BMW Three- and Four-Cylinder Diesel Engines
- Author
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Nikolai Ardey, Martin Kaufmann, Wolfgang Stütz, and Detlef Hiemesch
- Subjects
Diesel fuel ,Materials science ,law ,Mechanical engineering ,Cylinder (engine) ,law.invention - Published
- 2014
230. Die neuen Drei- und Vierzylinder-Dieselmotoren von BMW
- Author
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Detlef Hiemesch, Wolfgang Stütz, Nikolai Ardey, and Martin Kaufmann
- Subjects
Engineering ,business.industry ,Automotive Engineering ,business ,Automotive engineering - Published
- 2014
231. Outcome and prognostic factors in patients with mantle-cell lymphoma relapsing after autologous stem-cell transplantation: a retrospective study of the European Group for Blood and Marrow Transplantation (EBMT)
- Author
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Harry C. Schouten, Luc Fornecker, Jürgen Finke, R. J. Jarosinska, Stephen P. Robinson, Wendy Stevens, Edward Kanfer, Catherine Sebban, Michael Pfreundschuh, Marek Trneny, Christoph Schmid, Liisa Volin, Ariane Boumendil, Sascha Dietrich, Martin Kaufmann, Peter Dreger, Dominique Bordessoule, I. Avivi, José Luis Díez-Martín, Herve Finel, Jan J. Cornelissen, Johannes Schetelig, Guido Kobbe, Thomas Heinicke, Hematology, Cardiology, MUMC+: MA Hematologie (9), Interne Geneeskunde, RS: GROW - Oncology, and RS: GROW - R3 - Innovative Cancer Diagnostics & Therapy
- Subjects
Adult ,Male ,medicine.medical_specialty ,Kaplan-Meier Estimate ,Lymphoma, Mantle-Cell ,autologous stem-cell transplantation ,Transplantation, Autologous ,mantle cell lymphoma relapse ,Disease-Free Survival ,Autologous stem-cell transplantation ,medicine ,allogeneic stem-cell transplantation ,Humans ,Treatment Failure ,Aged ,Proportional Hazards Models ,Retrospective Studies ,Salvage Therapy ,Marrow transplantation ,business.industry ,Incidence (epidemiology) ,Standard treatment ,Retrospective cohort study ,Hematology ,Middle Aged ,medicine.disease ,Prognosis ,Confidence interval ,Surgery ,Transplantation ,Treatment Outcome ,Oncology ,Multivariate Analysis ,Mantle cell lymphoma ,Female ,Neoplasm Recurrence, Local ,business ,Stem Cell Transplantation - Abstract
Autologous stem-cell transplantation (autoSCT) is considered a standard treatment of non-frail patients with mantle cell lymphoma (MCL), but little is known about outcome of MCL patients relapsing after autoSCT. We therefore sought to analyse the outcome after autoSCT failure and the efficacy of a rescue stem-cell transplantation (SCT) in this setting. Patients with MCL were eligible if they had relapsed after autoSCT performed between 2000 and 2009. A total of 1054 patients could be identified in the EBMT registry. By contacting the transplant centres, a full dataset could be retrieved for 360 patients. Median overall survival (OS) after relapse of the whole study group was 19 months. A long (> 12 months) interval between autoSCT and relapse [P < 0.001, hazard ratio (HR) 0.62], primary refractory disease (P < 0.02, HR 1.92), prior high-dose ARA-C treatment (P = 0.04, HR 1.43), and the year of relapse (P = 0.02, HR 0.92) significantly influenced OS from relapse in multivariate analysis. Eighty patients (22%) received a rescue allogeneic SCT (alloSCT). Relapse incidence, non-relapse mortality, and OS 2 years after alloSCT was 33% [confidence interval (95% CI 21% to 45%)], 30% (95% CI 19% to 42%), and 46% (95% CI 33% to 59%), respectively. Remission duration after autoSCT was the only variable significantly affecting the outcome of salvage alloSCT. In contrast, rescue autoSCT was not associated with long-term disease control. However, individual patients survived long term even without salvage transplantation. MCL recurrence within 1 year after autoSCT has an extremely dismal outcome, while the prognosis of patients with longer remission durations after autoSCT is significantly better. AlloSCT may offer the possibility of durable survival when performed for patients with a remission duration of more than 12 months after first autoSCT, but the favourable effect of a salvage alloSCT in this setting needs further validation.
- Published
- 2014
232. Structural Analysis and Identification of PhuS as a Heme-Degrading Enzyme from Pseudomonas aeruginosa
- Author
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Martin Kaufmann, Michael J. Lee, Daniel Schep, Brian E. McLaughlin, and Zongchao Jia
- Subjects
Models, Molecular ,Chromatography, Gas ,Heme binding ,Protein Conformation ,Stereochemistry ,Heme ,Biology ,Crystallography, X-Ray ,Escherichia coli O157 ,medicine.disease_cause ,03 medical and health sciences ,chemistry.chemical_compound ,Protein structure ,Bacterial Proteins ,Structural Biology ,medicine ,Molecular Biology ,Escherichia coli ,Biotransformation ,030304 developmental biology ,chemistry.chemical_classification ,Carbon Monoxide ,0303 health sciences ,Pseudomonas aeruginosa ,Spectrum Analysis ,030302 biochemistry & molecular biology ,Cytochrome P450 ,Ascorbic acid ,Enzyme ,Biochemistry ,chemistry ,biology.protein ,Protein Binding - Abstract
Bacterial pathogens require iron for proliferation and pathogenesis. Pseudomonas aeruginosa is a prevalent Gram-negative opportunistic human pathogen that takes advantage of immunocompromised hosts and encodes a number of proteins for uptake and utilization of iron. Here we report the crystal structures of PhuS, previously known as the cytoplasmic heme-trafficking protein from P. aeruginosa, in both the apo- and the holo-forms. In comparison to its homologue ChuS from Escherichia coli O157:H7, the heme orientation is rotated 180° across the α-γ axis, which may account for some of the unique functional properties of PhuS. In contrast to previous findings, heme binding does not result in an overall conformational change of PhuS. We employed spectroscopic analysis and CO measurement by gas chromatography to analyze heme degradation, demonstrating that PhuS is capable of degrading heme using ascorbic acid or cytochrome P450 reductase-NADPH as an electron donor and produces five times more CO than ChuS. Addition of catalase slows down but does not stop PhuS-catalyzed heme degradation. Through spectroscopic and mass spectrometry analysis, we identified the enzymatic product of heme degradation to be verdoheme. These data taken together suggest that PhuS is a potent heme-degrading enzyme, in addition to its proposed heme-trafficking function.
- Published
- 2014
233. Cytochrome P450-mediated metabolism of vitamin D
- Author
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David E. Prosser, Glenville Jones, and Martin Kaufmann
- Subjects
Models, Molecular ,Cytochrome ,Protein Conformation ,Molecular Sequence Data ,QD415-436 ,Biology ,Biochemistry ,Endocrinology ,CYP24A1 ,CYP27B1 ,CYP27A1 ,Vitamin D and neurology ,Animals ,Humans ,Genetic Predisposition to Disease ,Amino Acid Sequence ,Renal Insufficiency, Chronic ,Vitamin D ,Steroid Hydroxylases ,Mutagenesis ,Thematic Review ,Cytochrome P450 ,Cell Biology ,vitamin D-dependent rickets ,Vitamin D Deficiency ,Hypercalcemia ,biology.protein ,CYP2R1 ,1,25-(OH)2D3 ,Signal transduction - Abstract
The vitamin D signal transduction system involves a series of cytochrome P450-containing sterol hydroxylases to generate and degrade the active hormone, 1α,25-dihydroxyvitamin D3, which serves as a ligand for the vitamin D receptor-mediated transcriptional gene expression described in companion articles in this review series. This review updates our current knowledge of the specific anabolic cytochrome P450s involved in 25- and 1α-hydroxylation, as well as the catabolic cytochrome P450 involved in 24- and 23-hydroxylation steps, which are believed to initiate inactivation of the vitamin D molecule. We focus on the biochemical properties of these enzymes; key residues in their active sites derived from crystal structures and mutagenesis studies; the physiological roles of these enzymes as determined by animal knockout studies and human genetic diseases; and the regulation of these different cytochrome P450s by extracellular ions and peptide modulators. We highlight the importance of these cytochrome P450s in the pathogenesis of kidney disease, metabolic bone disease, and hyperproliferative diseases, such as psoriasis and cancer; as well as explore potential future developments in the field.
- Published
- 2014
234. Time from Diagnosis to Treatment Does Not Affect Outcome in Intensively Treated Patients with Newly Diagnosed Acute Myeloid Leukemia
- Author
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Andreas Hochhaus, Ulrich Krümpelmann, Maxi Wass, Edgar Jost, Michael Kramer, Richard Noppeney, Martin Bornhäuser, Volker Kunzmann, Johannes Schetelig, Martin Kaufmann, Uwe Platzbecker, Gerhard Ehninger, Mathias Hänel, Björn Steffen, Norbert Frickhofen, Lars Fransecky, Friedrich Stoelzel, Stefan Klein, Christian Thiede, Kerstin Schäfer-Eckart, Alexander Kiani, Johannes Kullmer, Christoph Schliemann, Hermann Einsele, Andreas Neubauer, Malte von Bonin, Alwin Krämer, Regina Herbst, Claudia D. Baldus, Sebastian Scholl, Hubert Serve, Stefan W. Krause, Markus Schaich, Carsten Müller-Tidow, Christoph Röllig, Tim H. Brümmendorf, Dirk Niemann, Frank Heits, Tim Sauer, Ulrich Kaiser, Jan Moritz Middeke, and Jan Henrik Mikesch
- Subjects
medicine.medical_specialty ,Acute leukemia ,Prognostic variable ,Proportional hazards model ,business.industry ,Immunology ,Hazard ratio ,Medizin ,Myeloid leukemia ,Cell Biology ,Hematology ,Newly diagnosed ,Biochemistry ,Internal medicine ,Propensity score matching ,medicine ,Genetic risk ,business - Abstract
Background In newly diagnosed acute myeloid leukemia (AML), the general recommendation is to start treatment immediately after the diagnosis has been made. This paradigm is based both on the observation that untreated acute leukemia has a poor prognosis and on retrospective analyses demonstrating a shorter survival in younger AML patients (pts) in whom treatment was delayed by more than 5 days (Sekeres et al., 2009). A more recent single-center analysis came to a different conclusion, showing no prognostic effect for the time from diagnosis to treatment (TDT; Bertoli et al., 2013). We explored the relationship between TDT and prognosis on a large set of real-world data from the AML registry of the Study Alliance Leukemia (SAL) and compared it to the published cohorts. Methods The SAL runs a transregional AML registry in 46 treatment centers across Germany (NCT03188874). All registered patients with an intensive induction treatment, a minimum follow-up time of 12 months and no acute promyelocytic leukemia were selected (n=2,200). Treatment start was defined by the first day of cytarabine, whereas single agent hydroxyurea (HU) was labeled as pretreatment. We analyzed the influence of TDT on complete remission (CR), early death (ED) and overall survival (OS) in univariable analyses for each day of treatment delay, in groups of 0-5, 6-10, 11-15 and >15 days of TDT, and by using the restricted cubic spline (RCS) method for data modelling. In order to adjust for the influence of established prognostic variables on the outcomes, we used multivariable regression models and propensity score weighting. The influence of HU pretreatment on outcomes was investigated by introducing an interaction term between TDT and the presence of HU pretreatment. Results The median age was 59 years (y) (IQR 50-68), the proportion of pts with favorable, intermediate and adverse genetic risk according to ELN was 27%, 53%, and 20%; >95% of pts received induction treatment with standard 7+3. HU pretreatment was administered in 4% of pts. The median TDT was 3 days (IQR 2-6). Descriptive statistics after grouping of pts showed the highest median age and the lowest proportion of NPM1 mutated and favorable risk in the TDT group 11-15. Of all pts, 79% achieved a CR/CRi; unadjusted CR rates for the patient groups with TDT of 0-5, 6-10, 11-15 and >15 days were 80%, 77%, 74% and 76%, respectively (p=0.317). In multivariable analysis accounting for the influence of ELN risk, age, WBC, LDH, de novo versus secondary AML and ECOG, the OR for each additional day of TDT was 0.99 (95%-CI, 0.97-1.00; p=0.124). Four percent of pts died within the first 30 days from treatment start. The respective rates in the four TDT categories were 4.0%, 3.8%, 5.1% and 4.1% (p=0.960). In multivariable analysis, the OR for TDT was 1.01 (95%-CI, 0.98-1.05; p=0.549). After a median follow-up of 40 months, the 2-y OS of all pts was 51%. The unadjusted 2-y OS rates stratified by TDT of 0-5, 6-10, 11-15, >15 days were 52, 49, 46, and 51% (see Table 1 and Figure 1). The hazard ratio (HR) for each day of treatment delay was 1.00 (95%-CI; 0.99-1.01; p=0.317). In multivariable Cox regression analysis, the HR for TDT as continuous variable was 1.00 (95%-CI, 0.99-1.01; p=0.689). When OS was analyzed separately stratified for age ≤60 and >60 ys and for high versus lower initial WBC defined by a threshold of 50 x 109/L, no significant differences between TDT groups were observed. Multivariable models using TDT as a grouped variable or with RCS did not provide evidence for a significant influence of TDT on outcomes. Propensity score matching of pts in the four TDT groups did not reveal an influence on outcomes. The use of HU was not associated with CR, ED nor OS. Conclusion Our study on 2,200 newly diagnosed registry pts receiving consistent intensive induction with standard-dose cytarabine plus daunorubicin (7+3) suggests that TDT is not related to response or survival, neither in younger nor in older pts. Despite multivariable analyses, a bias towards longer TDT intervals in pts judged to be clinically stable by the treating physician cannot be excluded entirely. As treatment stratification in intensive first-line treatment of AML evolves, the TDT data suggests that it may be a safe and reasonable approach to wait for genetic and other laboratory test results in order to assign clinically stable pts to the best available treatment option before the start of intensive treatment. Disclosures Krämer: Daiichi-Sankyo: Honoraria, Membership on an entity's Board of Directors or advisory committees; Bayer: Research Funding; BMS: Research Funding; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees. Hänel:Roche: Honoraria; Amgen: Honoraria; Celgene: Other: advisory board; Novartis: Honoraria; Takeda: Other: advisory board. Jost:Daiichi: Honoraria; Sanofi: Honoraria; Gilead: Other: travel grants; Jazz Pharmaceuticals: Honoraria. Brümmendorf:Merck: Consultancy; Janssen: Consultancy; Novartis: Consultancy, Research Funding; Pfizer: Consultancy, Research Funding; University Hospital of the RWTH Aachen: Employment; Ariad: Consultancy. Krause:Siemens: Research Funding; Takeda: Honoraria; MSD: Honoraria; Gilead: Other: travel; Celgene Corporation: Other: Travel. Scholl:Novartis: Other: Project funding; Pfizer: Other: Advisory boards; Gilead: Other: Project funding; Daiichi Sankyo: Other: Advisory boards; AbbVie: Other: Advisory boards. Hochhaus:Pfizer: Research Funding; Novartis: Research Funding; BMS: Research Funding; Incyte: Research Funding; MSD: Research Funding. Kiani:Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Middeke:Sanofi: Research Funding, Speakers Bureau; Roche: Speakers Bureau; AbbVie: Consultancy, Speakers Bureau; Gilead: Consultancy; Janssen: Consultancy, Speakers Bureau; MSD: Consultancy. Thiede:AgenDix GmbH: Employment, Equity Ownership; Novartis: Research Funding, Speakers Bureau; Bayer: Research Funding; Daiichi-Sankyo: Speakers Bureau. Stoelzel:JAZZ Pharmaceuticals: Consultancy; Neovii: Other: Travel funding; Shire: Consultancy, Other: Travel funding. Platzbecker:Celgene: Consultancy, Honoraria, Research Funding; Abbvie: Consultancy, Honoraria; Novartis: Consultancy, Honoraria, Research Funding.
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- 2019
235. AtmoCube A1: airglow measurements in the mesosphere and lower thermosphere by spatial heterodyne interferometry
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Tom Neubert, Friedhelm Olschewski, Ralf Koppmann, Martin Riese, Klaus Mantel, Martin Kaufmann, and Heinz Rongen
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Physics ,010504 meteorology & atmospheric sciences ,0211 other engineering and technologies ,Airglow ,02 engineering and technology ,Atmospheric model ,01 natural sciences ,Mesosphere ,Depth sounding ,Interferometry ,Astronomical interferometer ,General Earth and Planetary Sciences ,ddc:620 ,Thermosphere ,Stratosphere ,021101 geological & geomatics engineering ,0105 earth and related environmental sciences ,Remote sensing - Abstract
The Institute for Atmospheric and Environmental Research at the University of Wuppertal and the Institute of Energy and Climate Research Stratosphere at Research Center Juelich developed a CubeSat payload for atmospheric research. The payload consists of a small interferometer for the observation of airglow near 762 nm. The line intensities of the oxygen A-band are used to derive temperatures in the mesosphere and lower thermosphere region. The temperature data will be used to analyze dynamical wave structures in the atmosphere. The interferometer technology chosen to measure the ro-vibrational structure of the O2 atmospheric band near 762 nm is a spatial heterodyne interferometer originally proposed by Connes in 1958. It can be designed to deliver extraordinary spectral resolution to resolve individual emission lines. The utilization of a two-dimensional imaging detector allows for recording interferograms at adjacent locations simultaneously. Integrated in a six-unit CubeSat, the instrument is designed for limb sounding of the atmosphere. The agility of a CubeSat will be used to sweep the line-of-sight through specific regions of interest to derive a three-dimensional image of an atmospheric volume using tomographic reconstruction techniques.
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- 2019
236. Analysis and correction of distortions in a spatial heterodyne spectrometer system
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Friedhelm Olschewski, Qiuyu Chen, Klaus Mantel, Oliver Wroblowski, Martin Kaufmann, Daikang Wei, Martin Riese, and Jilin Liu
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Heterodyne ,Physics ,Spectrometer ,business.industry ,Distortion (optics) ,Detector ,Astrophysics::Instrumentation and Methods for Astrophysics ,Division (mathematics) ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,010309 optics ,Optics ,Interference (communication) ,Optical transfer function ,0103 physical sciences ,Spatial frequency ,Electrical and Electronic Engineering ,business ,Engineering (miscellaneous) - Abstract
In this paper a method for correcting the radial distortion of interferograms generated by a spatial heterodyne spectrometer system is presented. Instead of utilizing calibration patterns, the distortion model parameters are estimated based on the distorted fringe features generated by projecting the straight interference stripes onto the detector. Comparisons between polynomial models and division models indicate that division models can deliver competitive performance on the reconstructed image with fewer parameters. Simulated interferograms based on ray-tracing are used to demonstrate the correction of errors in the spatial, phase, and spectral domain caused by optical distortion.
- Published
- 2019
237. Epicardial coronary artery spasm as cause of capecitabine-induced tako tsubo cardiomyopathy
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Peter Ong, Thomas Klag, Udo Sechtem, Anastasios Athanasiadis, Giulio Cantara, and Martin Kaufmann
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medicine.medical_specialty ,business.industry ,medicine.medical_treatment ,Percutaneous coronary intervention ,General Medicine ,Anterior Descending Coronary Artery ,medicine.disease ,Clopidogrel ,Coronary artery disease ,Internal medicine ,Coronary vasospasm ,Cardiology ,Medicine ,Sinus rhythm ,Myocardial infarction ,Cardiology and Cardiovascular Medicine ,business ,medicine.drug ,Cardiac catheterization - Abstract
Cardiotoxicity of fluoropyrimidines like the orally administered capecitabine and the intravenous 5-fluorouracil (5-FU) is a well-known clinical challenge [1, 2]. The cardiotoxic effects of both agents seem to occur through the same mechanisms [3]. However, capecitabine-induced cardiotoxicity is less common because it obtains its pharmacological active form through a three-step enzymatic conversion, while the last step is catalyzed by the enzyme thymidine phosphorylase, which is more active in neoplastic tissues [4, 5]. But this enzyme is also actively expressed in arteriosclerotic plaques, which is thought to be one potential mechanism leading to coronary side effects, especially in patients with a history of coronary artery disease [3]. Until today, numerous reports have shown cardiac side effects of fluoropyrimidines. However, there is no explicit evidence of capecitabine as a direct trigger for tako tsubo cardiomyopathy (TTC). Amongst other causes, coronary artery spasm is discussed as a potential cause of TTC [6]. Epicardial vasospasm is a widely accepted hypothetical pathomechanism of 5-FU-associated cardiac side effects [7, 8]. Therefore, fluoropyrimidines could be plausible triggers for TTC and the following case will strengthen this possible connection. An 81-year-old female with metastatic breast cancer was admitted to our emergency unit with acute chest pain and severe dyspnoea. The symptoms began at about 4 p.m., shortly after a 1-h workout as part of a diabetes group training. On the same day, in the morning at about 9 a.m., the patient had received the first dose of capecitabine (1,500 mg). The patient did not report any extraordinary emotional stress, but had a history of obstructive coronary artery disease. Five years ago she had undergone percutaneous coronary intervention in the left anterior descending coronary artery (LAD). The patient further suffered from insulin-dependent diabetes mellitus type 2, hypercholesterolemia, hypertension and peripheral vascular disease. On admission the symptoms were relieved by sublingual nitroglycerin, but recurred after a few minutes. The electrocardiogram (ECG) showed sinus rhythm with ST-segment elevations, which had not been detected in a routine ECG 3 weeks ago (Fig. 1a). High sensitive cardiac troponin T concentration was 282 pg/ml (n \ 14 pg/ml). The patient was treated with acetylsalicylic acid (500 mg intravenous), clopidogrel (600 mg orally) and heparin (5,000 units intravenous) because of the suspicion of acute ST-elevation myocardial infarction. No abnormalities were discovered by physical examination. Blood pressure was 140/63 mm/Hg. Cardiac catheterization was performed immediately. Ventriculography showed apical dyskinesia Electronic supplementary material The online version of this article (doi:10.1007/s00392-013-0636-4) contains supplementary material, which is available to authorized users.
- Published
- 2013
238. 7α-Hydroxylation of dehydroepiandrosterone does not interfere with the activation of glucocorticoids by 11β-hydroxysteroid dehydrogenase in EtC cerebellar neurons
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Martin Kaufmann, Haley A. Vecchiarelli, Zahrah Masheeb, Andres Gottfried-Blackmore, Karen Bulloch, Bruce S. McEwen, and Peter H. Jellinck
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endocrine system ,medicine.medical_specialty ,Neuroactive steroid ,Endocrinology, Diabetes and Metabolism ,Clinical Biochemistry ,Population ,Dehydroepiandrosterone ,Biology ,Real-Time Polymerase Chain Reaction ,Biochemistry ,Neuroprotection ,Cell Line ,Mice ,chemistry.chemical_compound ,Endocrinology ,Corticosterone ,Cerebellum ,Internal medicine ,polycyclic compounds ,medicine ,Animals ,skin and connective tissue diseases ,education ,Receptor ,Glucocorticoids ,Molecular Biology ,Neurons ,education.field_of_study ,Cell Biology ,Metabolism ,chemistry ,Molecular Medicine ,11-beta-Hydroxysteroid Dehydrogenases ,human activities ,hormones, hormone substitutes, and hormone antagonists ,Glucocorticoid ,medicine.drug - Abstract
The neuroprotective action of dehydroepiandrosterone (DHEA) in the absence of a known specific receptor has been attributed to its metabolism by different cell types in the brain to various steroids, with a preference to its 7-hydroxylated products. The E(t)C cerebellar granule cell line converts DHEA almost exclusively to 7α-hydroxy-DHEA (7α-OH-DHEA). It has been postulated that DHEA's 7-OH and 7-oxo metabolites can decrease glucocorticoid levels by an interactive mechanism involving 11β-hydroxysteroid dehydrogenase (11β-HSD). In order to study the relationship of 7-hydroxylation of DHEA and glucocorticoid metabolism in intact brain cells, we examined whether E(t)C cerebellar neurons, which are avid producers of 7α-OH-DHEA, could also metabolize glucocorticoids. We report that E(t)C neuronal cells exhibit 11β-HSD1 reductase activity, and are able to convert 11-dehydrocorticosterone into corticosterone, whereas they do not demonstrate 11β-HSD2 dehydrogenase activity. Consequently, E(t)C cells incubated with DHEA did not yield 7-oxo- or 7β-OH-DHEA. Our findings are supported by the reductive environment of E(t)C cells through expression of hexose-6-phosphate dehydrogenase (H6PDH), which fosters 11β-HSD1 reductase activity. To further explore the role of 7α-OH-DHEA in E(t)C neuronal cells, we examined the effect of preventing its formation using the CYP450 inhibitor ketoconazole. Treatment of the cells with this drug decreased the yield of 7α-OH-DHEA by about 75% without the formation of alternate DHEA metabolites, and had minimal effects on glucocorticoid conversion. Likewise, elevated levels of corticosterone, the product of 11β-HSD1, had no effect on the metabolic profile of DHEA. This study shows that in a single population of whole-cells, with a highly reductive environment, 7α-OH-DHEA is unable to block the reducing activity of 11β-HSD1, and that 7-hydroxylation of DHEA does not interfere with the activation of glucocorticoids. Our investigation on the metabolism of DHEA in E(t)C neuronal cells suggest that other alternate mechanisms must be at play to explain the in vivo anti-glucocorticoid properties of DHEA and its 7-OH-metabolites.
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- 2013
239. Comprehensive and interactive temporal query processing with SAP HANA
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Franz Färber, Donald Kossmann, Peter M. Fischer, Martin Kaufmann, and Panagiotis Vagenas
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Structure (mathematical logic) ,SQL ,Computer science ,SAP HANA ,General Engineering ,Timeline ,Data mining ,ddc:004 ,computer.software_genre ,computer ,Column (database) ,Temporal database ,computer.programming_language - Abstract
In this demo, we present a prototype of a main memory database system which provides a wide range of temporal operators featuring predictable and interactive response times. Much of real-life data is temporal in nature, and there is an increasing application demand for temporal models and operations in databases. Nevertheless, SQL:2011 has only recently overcome a decade-long standstill on standardizing temporal features. As a result, few database systems provide any temporal support, and even those only have limited expressiveness and poor performance. Our prototype combines an in-memory column store and a novel, generic temporal index structure named Timeline Index. As we will show on a workload based on real customer use cases, it achieves predictable and interactive query performance for a wide range of temporal query types and data sizes.
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- 2013
240. Storing and processing temporal data in a main memory column store
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Martin Kaufmann and Donald Kossmann
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Database ,Computer science ,SAP HANA ,General Engineering ,Overhead (computing) ,Timeline ,Data mining ,computer.software_genre ,Representation (mathematics) ,Data structure ,computer ,Column (database) ,Temporal database - Abstract
Managing and accessing temporal data is of increasing importance in industry. So far, most companies model the time dimension on the application layer rather than pushing down the operators to the database, which leads to a significant performance overhead. The goal of this PhD thesis is to develop a native support of temporal features for SAP HANA, which is a commercial in-memory column store database system. We investigate different alternatives to store temporal data physically and analyze the trade-offs arising from different memory layouts which cluster the data either by time or by space dimension. Taking into account the underlying physical representation, different temporal operators such as temporal aggregation, time travel and temporal join have to be executed efficiently. We present a novel data structure called Timeline Index and algorithms based on this index, which have a very competitive performance for all temporal operators beating existing best-of-breed approaches by factors, sometimes even by orders of magnitude. The results of this thesis are currently being integrated into HANA, with the goal of being shipped to the customers as a productive release within the next few months.
- Published
- 2013
241. Role of gravity waves in the forcing of quasi two-day waves in the mesosphere: An observational study
- Author
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Silvio Kalisch, Martin Riese, Peter Preusse, Manfred Ern, and Martin Kaufmann
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Physics ,Atmospheric Science ,Jet (fluid) ,Astrophysics::High Energy Astrophysical Phenomena ,Geophysics ,Forcing (mathematics) ,Vorticity ,Atmospheric sciences ,Physics::Geophysics ,Space and Planetary Science ,Drag ,Potential vorticity ,Physics::Space Physics ,Earth and Planetary Sciences (miscellaneous) ,Gravity wave ,Thermosphere ,Physics::Atmospheric and Oceanic Physics ,Geostrophic wind - Abstract
[1] Amplitudes of quasi two-day waves (QTDWs) are derived from temperature observations of the High Resolution Dynamics Limb Sounder and Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) satellite instruments. In particular, a global climatology of QTDW amplitudes is derived from 10 years of SABER data, covering the mesosphere and lower thermosphere. This climatology is compared with geostrophic winds and climatologies of gravity wave (GW) momentum flux and GW drag absolute values derived from the same data set. We find that QTDWs are forced shortly after the maximum of the mesospheric summertime zonal wind jet in regions of jet instability where the meridional gradient of quasi-geostrophic zonal mean potential vorticity is strongly negative. The jet instability regions are closely linked to enhanced GW drag that likely seeds those instabilities by decelerating the jet and causing the jet curvature responsible for the negative potential vorticity gradient. The vertical phase structure and the Eliassen-Palm flux of the QTDWs are derived from SABER data and investigated. It is shown that QTDWs propagate upward starting from the jet instability regions. They exert eastward drag in the jet core, and strong westward drag at higher altitudes. Strikingly, the QTDWs are forced in regions where the global distribution of GWs exhibits a characteristic longitudinal structure caused by the GW source patterns in the summer hemisphere. This longitudinal structure might play an important role in the forcing of QTDWs; however, no clear link has been found to the observed QTDW zonal wavenumbers.
- Published
- 2013
242. Serum 24,25-dihydroxyvitamin D
- Author
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Laura A, Graeff-Armas, Martin, Kaufmann, Elizabeth, Lyden, and Glenville, Jones
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Male ,24,25-Dihydroxyvitamin D 3 ,Renal Dialysis ,Dietary Supplements ,Ergocalciferols ,Humans ,Female ,Vitamins ,Middle Aged ,Renal Insufficiency, Chronic ,Vitamin D Deficiency ,Aged ,Cholecalciferol - Abstract
While vitamin D deficiency is common in patients with end stage renal disease on dialysis and treatment with Vitamin D680 samples from three controlled trials of Vitamin DThe subjects given Vitamin DWe conclude that the enzymatic activity of CYP24A1 is abnormal in end stage renal patients on dialysis. These trials were registered on clinicaltrials.govNCT00511225 on 8/1/2007; NCT01325610 on 1/17/2011; and NCT01675557 on 8/28/2012.
- Published
- 2016
243. Improved Screening Test for Idiopathic Infantile Hypercalcemia Confirms Residual Levels of Serum 24,25-(OH)
- Author
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Martin, Kaufmann, Nicole, Morse, Billy Joe, Molloy, Donald P, Cooper, Karl Peter, Schlingmann, Arnaud, Molin, Marie Laure, Kottler, J Christopher, Gallagher, Laura, Armas, and Glenville, Jones
- Subjects
24,25-Dihydroxyvitamin D 3 ,Genotype ,Mutation ,Hypercalcemia ,Humans ,Female ,Middle Aged ,Vitamin D3 24-Hydroxylase ,Mass Spectrometry ,Aged ,Chromatography, Liquid - Abstract
CYP24A1 mutations are now accepted as a cause of idiopathic infantile hypercalcemia (IIH). A rapid liquid-chromatography tandem mass spectrometry (LC-MS/MS)-based blood test enabling measurement of the 25-OH-D
- Published
- 2016
244. Atmospheric gravity waves observation from a lunar base
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Rui Song and Martin Kaufmann
- Subjects
Gravity (chemistry) ,010504 meteorology & atmospheric sciences ,Atmospheric wave ,Pedosphere ,0211 other engineering and technologies ,Biosphere ,Global change ,02 engineering and technology ,Geophysics ,01 natural sciences ,Physics::Geophysics ,Atmosphere ,Lithosphere ,Physics::Space Physics ,Satellite ,Astrophysics::Earth and Planetary Astrophysics ,Geology ,021101 geological & geomatics engineering ,0105 earth and related environmental sciences - Abstract
Global change refers to changes in the atmosphere, oceans, biosphere, pedosphere and lithosphere over the past century. It is a long process with large dimensions. Nowadays, satellite provides a regular platform to take measurements of all sensitivity factors of Earth. However, measurements taken from satellite platform is only available in a limited region on Earth with a short observing time. This is a new challenge for the purpose to observe large scale, long period Earth phenomena. In recent years, there has been a renewed interest in the development of robotic and manned exploration missions to the Moon. Here we propose the possibility of observing large-scale Earth phenomena from a lunar base. Atmospheric gravity waves, which is of interest to atmospheric research and important to the global change, are discussed as a sensitivity factor for lunar-based observation.
- Published
- 2016
245. ParTime
- Author
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Damien Profeta, Markus Pilman, Donald Kossmann, Martin Kaufmann, and Florian Köhl
- Subjects
Data parallelism ,Computer science ,Computation ,Parallel database ,Search engine indexing ,Parallel algorithm ,020207 software engineering ,Timeline ,02 engineering and technology ,computer.software_genre ,Temporal database ,Data model ,020204 information systems ,0202 electrical engineering, electronic engineering, information engineering ,Benchmark (computing) ,Data mining ,computer - Abstract
This paper presents ParTime, a parallel algorithm for temporal aggregation. Temporal aggregation is one of the most important, yet most complex temporal query operators. It has been extensively studied in the past, but so far there has only been one attempt to parallelize this operator. ParTime supports data parallelism and has a number of additional advantages: It supports the full bitemporal data model, it requires no a-priori indexing, it supports shared computation, and it runs well on modern hardware (i.e., NUMA machines with large main memories). We implemented ParTime in a parallel database system and carried out comprehensive performance experiments with a real workload from the airline industry and a synthetic benchmark, the TPC-BiH benchmark. The results show that ParTime significantly outperforms any other available temporal database system. Furthermore, the results show that ParTime is competitive as compared to the Timeline Index, the best known technique to process temporal queries from the research literature and which is based on pre-computation and indexing.
- Published
- 2016
246. Matching for the MICA-129 polymorphism is beneficial in unrelated hematopoietic stem cell transplantation
- Author
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Donald Bunjes, Carlheinz Mueller, Jochen Casper, Kerstin Schaefer-Eckart, Gernot Stuhler, Joannis Mytilineos, Sebastian Freitag, Martin Gramatzki, Bernd Hertenstein, Stefan Klein, Mark Ringhoffer, Dietger Niederwieser, Chrysanthi Tsamadou, Eva Wagner, Renate Arnold, Martin Kaufmann, Mohammed Wattad, Daphne Mytilineos, Michael Pfreundschuh, Daniel Fuerst, Hermann Einsele, Gerald Wulf, Bertram Glass, Christine Neuchel, and Hubert Schrezenmeier
- Subjects
0301 basic medicine ,Adult ,Male ,medicine.medical_specialty ,Adolescent ,medicine.medical_treatment ,Immunology ,Hematopoietic stem cell transplantation ,Human leukocyte antigen ,Major histocompatibility complex ,Biochemistry ,Gastroenterology ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Internal medicine ,medicine ,Minor histocompatibility antigen ,Humans ,Aged ,Polymorphism, Genetic ,biology ,Donor selection ,business.industry ,Histocompatibility Testing ,Histocompatibility Antigens Class I ,Hematopoietic Stem Cell Transplantation ,Cell Biology ,Hematology ,Middle Aged ,NKG2D ,Natural killer T cell ,Survival Analysis ,Tissue Donors ,Surgery ,Transplantation ,stomatognathic diseases ,030104 developmental biology ,Genetic Loci ,Multivariate Analysis ,biology.protein ,Female ,business ,030215 immunology - Abstract
Major histocompatibility complex class I polypeptide-related sequence A (MICA) is a highly polymorphic ligand of the activating NKG2D receptor on natural killer (NK) cells, γδ-T cells, and NKT cells. MICA incompatibilities have been associated with an increased graft-versus-host disease (GVHD) incidence, and the MICA-129 (met/val) dimorphism has been shown to influence NKG2D signaling in unrelated hematopoietic stem cell transplantation (uHSCT). We investigated the effect of MICA matching on survival after uHSCT. We sequenced 2172 patients and their respective donors for MICA. All patients and donors were high-resolution HLA-typed and matched for 10/10 (n = 1379), 9/10 (n = 636), or 8/10 (n = 157) HLA alleles. Within each HLA match group, cases matched and mismatched for MICA and MICA-129 were analyzed for the end points overall survival (OS), disease-free survival (DFS), nonrelapse mortality (NRM), relapse-incidence (RI), and GVHD. Mismatches at the MICA locus as well as MICA-129 increased with the number of HLA mismatches (MICA mismatched 10/10, 9.2% [n = 127]; 9/10, 22.3% [n = 142]; 8/10, 38.2% [n = 60]; MICA-129 mismatched 10/10, 3.9% [n = 54]; 9/10, 10.2% [n = 65]; 8/10, 17.2% [n = 27]). Adverse OS was observed in the 10/10 match group if MICA-129 was mismatched (10/10, hazard ratio [HR], 1.77; confidence interval [CI], 1.22-2.57; P = .003). MICA-129 mismatches correlated with a significantly worse outcome for DFS in the 10/10 HLA match group (HR, 1.77; CI, 1.26-2.50; P = .001). Higher rates of aGVHD were seen in MICA-129 mismatched cases. Our results indicate that MICA-129 matching is relevant in uHSCT. Prospective typing of patients and donors in unrelated donor search may identify mismatches for MICA-129, and compatible donor selection may improve outcome for this small but high-risk subgroup.
- Published
- 2016
247. Satellite observations of middle atmosphere gravity wave activity and dissipation during recent stratospheric warmings
- Author
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Isabell Krisch, John C. Gille, Michael J. Schwartz, Quang Thai Trinh, Martin Riese, Manfred Ern, Jörn Ungermann, Yajun Zhu, Martin G. Mlynczak, Martin Kaufmann, James M. Russell, and Peter Preusse
- Subjects
Atmosphere ,010504 meteorology & atmospheric sciences ,Meteorology ,Environmental science ,Satellite ,Gravity wave ,Dissipation ,010502 geochemistry & geophysics ,Atmospheric sciences ,01 natural sciences ,Physics::Atmospheric and Oceanic Physics ,0105 earth and related environmental sciences - Abstract
Sudden stratospheric warmings (SSWs) are circulation anomalies in the polar region during winter. They mostly occur in the Northern Hemisphere and affect also surface weather and climate. Both planetary waves and gravity waves contribute to the onset and evolution of SSWs. While the role of planetary waves for SSW evolution has been recognized, the effect of gravity waves is still not fully understood, and has not been comprehensively analyzed based on global observations. In particular, information on the gravity wave driving of the background winds during SSWs is still missing. We investigate the boreal winters 2001/2002 until 2013/2014. Absolute gravity wave momentum fluxes and gravity wave dissipation (potential drag) are estimated from temperature observations of the satellite instruments HIRDLS and SABER. In agreement with previous work, we find that sometimes gravity wave activity is enhanced before the central date of major SSWs, particularly during vortex-split events. Often, SSWs are associated with polar-night jet oscillation (PJO) events. For these events, we find that gravity wave activity is strongly suppressed when winds reverse from eastward to westward (usually after the central date of a major SSW). In addition, gravity wave potential drag at the bottom of the newly forming eastward directed jet is remarkably weak, while considerable potential drag at the top of the jet likely contributes to the downward propagation of both the jet and the new elevated stratopause. During PJO events, we also find some indication for poleward propagation of gravity waves. Another striking finding is that obviously localized gravity wave sources, likely mountain waves and jet-generated gravity waves, play an important role during the evolution of SSWs and potentially contribute to the triggering of SSWs by preconditioning the shape of the polar vortex. The distribution of these hot spots is highly variable and strongly depends on the zonal and meridional shape of the background wind field, indicating that a pure zonal average view sometimes is a too strong simplification for the strongly perturbed conditions during the evolution of SSWs.
- Published
- 2016
248. Karyotype complexity and prognosis in acute myeloid leukemia
- Author
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Claudia D. Baldus, Michael Kramer, Hubert Serve, Johannes Schetelig, Gerhard Ehninger, Martin Bornhäuser, Mathias Hänel, Uta Oelschlägel, Brigitte Mohr, Friedrich Stölzel, Jan Moritz Middeke, Hermann Einsele, Reingard Stuhlmann, Kristina Sohlbach, Jiri Mayer, Markus Schaich, Wolfgang E. Berdel, Tilmann Bochtler, Uwe Platzbecker, Martin Kaufmann, Kerstin Schäfer-Eckart, Andreas Neubauer, Stefan W. Krause, Christoph Röllig, Alwin Krämer, and Regina Herbst
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Adult ,Male ,0301 basic medicine ,Oncology ,medicine.medical_specialty ,Myeloid ,Adolescent ,Karyotype ,Chromosomal translocation ,Kaplan-Meier Estimate ,Biology ,Polyploidy ,Young Adult ,03 medical and health sciences ,European LeukemiaNet ,0302 clinical medicine ,Internal medicine ,medicine ,Humans ,In patient ,ddc:610 ,Young adult ,Aged ,Randomized Controlled Trials as Topic ,Aged, 80 and over ,Chromosome Aberrations ,Myeloid leukemia ,Hematology ,Middle Aged ,Prognosis ,medicine.disease ,Leukemia, Myeloid, Acute ,Leukemia ,030104 developmental biology ,medicine.anatomical_structure ,Karyotyping ,030220 oncology & carcinogenesis ,Immunology ,Original Article ,Female - Abstract
A complex aberrant karyotype consisting of multiple unrelated cytogenetic abnormalities is associated with poor prognosis in patients with acute myeloid leukemia (AML). The European Leukemia Net classification and the UK Medical Research Council recommendation provide prognostic categories that differ in the definition of unbalanced aberrations as well as the number of single aberrations. The aim of this study on 3526 AML patients was to redefine and validate a cutoff for karyotype complexity in AML with regard to adverse prognosis. Our study demonstrated that (1) patients with a pure hyperdiploid karyotype have an adverse risk irrespective of the number of chromosomal gains, (2) patients with translocation t(9;11)(p21∼22;q23) have an intermediate risk independent of the number of additional aberrations, (3) patients with ⩾4 abnormalities have an adverse risk per se and (4) patients with three aberrations in the absence of abnormalities of strong influence (hyperdiploid karyotype, t(9;11)(p21∼22;q23), CBF-AML, unique adverse-risk aberrations) have borderline intermediate/adverse risk with a reduced overall survival compared with patients with a normal karyotype.
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- 2016
249. Azacitidine in combination with intensive induction chemotherapy in older patients with acute myeloid leukemia : The AML-AZA trial of the Study Alliance Leukemia
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Maria Eveslage, Richard Noppeney, T Butterfaß-Bahloul, Wolfgang E. Berdel, Martin Kaufmann, M Stelljes, Norbert Frickhofen, Christoph Röllig, Christian Thiede, Björn Steffen, Alexander Kiani, A. Reichle, G. Ehninger, Carsten Müller-Tidow, Ralph Naumann, Roland Repp, R. Wagner, U. Thiem, T H Brümmendorf, Ulrich Kaiser, Mathias Hänel, Norbert Schmitz, Michael G. Kiehl, Andreas Neubauer, Aristoteles Giagounidis, Claudia D. Baldus, Hartmut Link, Petra Tschanter, Martin Dugas, Steffen Koschmieder, Hubert Serve, Stefan W. Krause, W. Herr, Joachim Gerss, Volker Kunzmann, Kerstin Schäfer-Eckart, Utz Krug, Martin Görner, A. Koschmieder, Katharina Götze, and Rudolf Peceny
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Male ,0301 basic medicine ,Oncology ,Antimetabolites, Antineoplastic ,Cancer Research ,medicine.medical_specialty ,Myeloid ,medicine.medical_treatment ,Azacitidine ,Medizin ,Pharmacology ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,Antineoplastic Combined Chemotherapy Protocols ,medicine ,Humans ,Survival analysis ,Aged ,Chemotherapy ,business.industry ,Daunorubicin ,Remission Induction ,Cytarabine ,Induction chemotherapy ,Myeloid leukemia ,Induction Chemotherapy ,Hematology ,Middle Aged ,medicine.disease ,Survival Analysis ,Leukemia, Myeloid, Acute ,Leukemia ,030104 developmental biology ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Cytogenetic Analysis ,Female ,business ,medicine.drug - Abstract
DNA methylation changes are a constant feature of acute myeloid leukemia. Hypomethylating drugs such as azacitidine are active in acute myeloid leukemia (AML) as monotherapy. Azacitidine monotherapy is not curative. The AML-AZA trial tested the hypothesis that DNA methyltransferase inhibitors such as azacitidine can improve chemotherapy outcome in AML. This randomized, controlled trial compared the efficacy of azacitidine applied before each cycle of intensive chemotherapy with chemotherapy alone in older patients with untreated AML. Event-free survival (EFS) was the primary end point. In total, 214 patients with a median age of 70 years were randomized to azacitidine/chemotherapy (arm-A) or chemotherapy (arm-B). More arm-A patients (39/105; 37%) than arm-B (25/109; 23%) showed adverse cytogenetics (P=0.057). Adverse events were more frequent in arm-A (15.44) versus 13.52 in arm-B, (P=0.26), but early death rates did not differ significantly (30-day mortality: 6% versus 5%, P=0.76). Median EFS was 6 months in both arms (P=0.96). Median overall survival was 15 months for patients in arm-A compared with 21 months in arm-B (P=0.35). Azacitidine added to standard chemotherapy increases toxicity in older patients with AML, but provides no additional benefit for unselected patients.
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- 2016
250. Autosomal-Recessive Mutations in SLC34A1 Encoding Sodium-Phosphate Cotransporter 2A Cause Idiopathic Infantile Hypercalcemia
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Miroslav Dumić, Derya Bulus, Birgitta Kranz, Przemysław Sikora, Veselin Boyadzhiev, Nati Hernando, Aneta Gawlik, Elżbieta Ciara, Elena Levtchenko, Justyna Ruminska, Ian C. Forster, Matthias Galiano, Ewa Pronicka, Glenville Jones, Karl P. Schlingmann, Robert Kleta, Martin Kaufmann, Asaf Vivante, René J. M. Bindels, Teoman Akcay, Ludwig Patzer, Stephan Rust, Monica Patti, Benjamin Dekel, Elisabeth A.M. Cornelissen, Carsten A. Wagner, Martin Konrad, Ismail Dursun, University of Zurich, and Konrad, Martin
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0301 basic medicine ,medicine.medical_specialty ,Candidate gene ,610 Medicine & health ,Genes, Recessive ,Biology ,Sodium-Phosphate Cotransporter Proteins, Type IIa ,Infant, Newborn, Diseases ,10052 Institute of Physiology ,activated Vitamin D ,Mice ,03 medical and health sciences ,CYP24A1 ,Clinical Research ,Internal medicine ,medicine ,Vitamin D and neurology ,Animals ,Humans ,Hypercalciuria ,hypercalciuria ,Mice, Knockout ,Kidney ,2727 Nephrology ,Sodium-Phosphate Cotransporter Proteins ,Infant, Newborn ,genetic renal disease ,Infant ,General Medicine ,medicine.disease ,mineral metabolism ,030104 developmental biology ,medicine.anatomical_structure ,Endocrinology ,Renal disorders Radboud Institute for Molecular Life Sciences [Radboudumc 11] ,Nephrology ,10076 Center for Integrative Human Physiology ,molecular genetics ,Mutation ,Failure to thrive ,Hypercalcemia ,570 Life sciences ,biology ,Nephrocalcinosis ,medicine.symptom ,Metabolism, Inborn Errors - Abstract
Item does not contain fulltext Idiopathic infantile hypercalcemia (IIH) is characterized by severe hypercalcemia with failure to thrive, vomiting, dehydration, and nephrocalcinosis. Recently, mutations in the vitamin D catabolizing enzyme 25-hydroxyvitamin D3-24-hydroxylase (CYP24A1) were described that lead to increased sensitivity to vitamin D due to accumulation of the active metabolite 1,25-(OH)2D3. In a subgroup of patients who presented in early infancy with renal phosphate wasting and symptomatic hypercalcemia, mutations in CYP24A1 were excluded. Four patients from families with parental consanguinity were subjected to homozygosity mapping that identified a second IIH gene locus on chromosome 5q35 with a maximum logarithm of odds (LOD) score of 6.79. The sequence analysis of the most promising candidate gene, SLC34A1 encoding renal sodium-phosphate cotransporter 2A (NaPi-IIa), revealed autosomal-recessive mutations in the four index cases and in 12 patients with sporadic IIH. Functional studies of mutant NaPi-IIa in Xenopus oocytes and opossum kidney (OK) cells demonstrated disturbed trafficking to the plasma membrane and loss of phosphate transport activity. Analysis of calcium and phosphate metabolism in Slc34a1-knockout mice highlighted the effect of phosphate depletion and fibroblast growth factor-23 suppression on the development of the IIH phenotype. The human and mice data together demonstrate that primary renal phosphate wasting caused by defective NaPi-IIa function induces inappropriate production of 1,25-(OH)2D3 with subsequent symptomatic hypercalcemia. Clinical and laboratory findings persist despite cessation of vitamin D prophylaxis but rapidly respond to phosphate supplementation. Therefore, early differentiation between SLC34A1 (NaPi-IIa) and CYP24A1 (24-hydroxylase) defects appears critical for targeted therapy in patients with IIH.
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- 2016
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