Dokument-ID Dokumenttyp Autoren/innen Persönliche Herausgeber/innen Haupttitel Abstract Auflage Verlagsort Verlag Herausgeber (Institution) Erscheinungsjahr Titel des übergeordneten Werkes Jahrgang/Band ISBN Veranstaltung Veranstaltungsort Beginndatum der Veranstaltung Enddatum der Veranstaltung Ausgabe/Heft Erste Seite Letzte Seite URN DOI Lizenz Datum der Freischaltung OPUS4-30492 Zeitschriftenartikel Scharkoi, O.; Becker, Roland; Esslinger, Susanne; Weber, M.; Nehls, Irene Predicting sites of cytochrome P450-mediated hydroxylation applied to CYP3A4 and hexabromocyclododecane This article describes a simple and quick in silico method for the prediction of cytochrome P450 (CYP)-mediated hydroxylation of drug-like compounds. Testosterone and progesterone, two known substrates of CYP3A4, are used to test the method. Further, we apply the procedure to predict sites of hydroxylation of isomers of the flame retardant hexabromocyclododecane by CYP3A4. Within the method, the compound is rotated in the binding pocket of the cytochrome, so that each hydrogen under consideration is placed near the active centre. Afterwards, short molecular dynamics simulations are provided for each step of the rotation. All steps of the simulation are compared concerning the distances between the hydrogens and the active centre and the corresponding energies. The computational results correlate well with experimental results. New York, NY Gordon and Breach 2015 Molecular simulation 41 7 538 546 10.1080/08927022.2014.898845 2016-02-20 OPUS4-34161 Zeitschriftenartikel Schallschmidt, Kristin; Becker, Roland; Zwaka, H.; Menzel, R.; Johnen, D.; Fischer-Tenhagen, C.; Rolff, J.; Nehls, Irene In vitro cultured lung cancer cells are not suitable for animal-based breath biomarker detection In vitro cultured lung cancer cell lines were investigated regarding the possible identification of volatile organic compounds as potential biomarkers. Gas samples from the headspace of pure culture medium and from the cultures of human lung adenocarcinoma cell lines A549 and Lu7466 were exposed to polypropylene fleece in order to absorb odour components. Sniffer dogs were trained with loaded fleeces of both cell lines, and honey bees were trained with fleeces exposed to A549. Afterwards, their ability to distinguish between cell-free culture medium odour and lung cancer cell odour was tested. Neither bees nor dogs were able to discriminate between odours from the cancer cell cultures and the pure culture medium. Solid phase micro extraction followed by gas chromatography with mass selective detection produced profiles of volatiles from the headspace offered to the animals. The profiles from the cell lines were largely similar; distinct differences were based on the decrease of volatile culture medium components due to the cells' metabolic activity. In summary, cultured lung cancer cell lines do not produce any biomarkers recognizable by animals or gas chromatographic analysis. Bristol IOP 2015 Journal of breath research 9 2 027103-1 027103-10 10.1088/1752-7155/9/2/027103 2016-02-20 OPUS4-33165 Beitrag zu einem Sammelband Nehls, Irene; Schallschmidt, Kristin; Becker, Roland; Fischer-Tenhagen, C.; Johnen, D.; Leschber, G.; Frese, S.; Neudecker, J.; Walles, T. Schüler, C.; Püschel, K. BIOAIR - Ein interdisziplinäres Projekt zur Bestimmung von Krebsmarkern in der Atemluft Wie viele Forschergruppen, haben auch wir uns das langfristige Ziel gesetzt, einen Beitrag bei der Beantwortung der Frage zu leisten, was Hunde riechen, wenn sie Krebs erschnüffeln. Dabei sollen die Hunde nicht nur anzeigen, ob eine Atemluftprobe positiv oder negativ ist, sondern sie sollen auch aktiv eingebunden werden in den systematischen Suchprozess nach detektierbaren Biomarkern. So ist geplant, dass mittels eines präparativen Fraktionssammlers definierte Schnitte des Gaschromatogramms einzeln oder in möglichen Kombinationen auf das Adsorbervlies gebracht werden, um im Hundetraining eingesetzt zu werden. In analoger Weise könnte auch mit spezifischen Kandidatensubstanzen verfahren werden. Dr. Kovac Universität Hamburg - Institut für Rechtsmedizin 2015 Faszinosum Spürhunde - Quo vadis? 30 978-3-8300-8763-2 93 101 2016-02-20 OPUS4-33741 Vortrag Becker, Roland Analysis of volatile and semi-volatile components in hydrochar: prospects and challenges 2015 International Biochar Symposium 2015 Biochar - Contribution to Sustainable Agriculture International Biochar Symposium 2015 Biochar - Contribution to Sustainable Agriculture Potsdam 2015-05-28 2015-05-29 2016-02-20 OPUS4-32828 Posterpräsentation Becker, Roland Chemische Analytik in der Forensik: Der Alkoholkonsummarker Ethylglucuronid 2015 ANAKON 2015 ANAKON 2015 Graz (Österreich) 2015-03-23 2015-03-26 2016-02-20 OPUS4-35558 misc Sauer, Andreas; Scharf, Holger; Becker, Roland Bericht zum 21. BAM-Ringversuch "Altlasten" Präsentation der Ergebnisse eines Ringversuchs zur Kompetenzbewertung von Prüflaboratorien auf dem Gebiet der anorganischen und organischen Bodenanalytik. Berlin Bundesanstalt für Materialforschung und -prüfung (BAM) 2015 1 234 urn:nbn:de:kobv:b43-355586 http://www.gesetze-im-internet.de/urhg/index.html 2016-03-29 OPUS4-33981 Posterpräsentation Becker, Roland Odour reference materials and training concepts for sniffer dogs 2015 International Association of Breath Research Summit 2015 International Association of Breath Research Summit 2015 Wien (Österreich) 2015-09-14 2015-09-16 2016-02-20 OPUS4-33984 Posterpräsentation Becker, Roland Odour reference material and training concepts for sniffer dogs 2015 International Conference on Medical Bio-Detection International Conference on Medical Bio-Detection Cambridge (England) 2015-09-15 2015-09-16 2016-02-20 OPUS4-34991 Zeitschriftenartikel Schallschmidt, Kristin; Becker, Roland; Jung, Christian; Rolff, J.; Fichtner, I. Investigation of cell culture volatilomes using solid phase micro extraction: options and pitfalls exemplified with adenocarcinoma cell lines Three strategies to sample volatile organic compounds (VOC) from lung cancer cell lines cultured in vitro were compared. Headspace solid phase microextraction was applied in situ to culture flasks and alternatively to subsamples of headspace gas or to nutrient solution subsamples followed by gas chromatography-mass spectrometry. The direct quantification of 55 VOC in the headspace of cell cultures was validated and is discussed with respect to reproducibility and system-related interferences. The role of the VOC background from culture media and usually employed polystyrene culture vessels is examined and was seen to invoke potentially misleading conclusions. The commercial A549 and two further adenocarcinoma cell lines displayed largely similar VOC profiles with distinct differences regarding certain individual substances. There is evidence for the inappropriateness of the standard cell culturing methods in the search for volatile cancer markers. Amsterdam [u.a.] Elsevier B.V. 2015 Journal of chromatography B 1006 158 166 10.1016/j.jchromb.2015.10.004 2016-02-20 OPUS4-34940 Zeitschriftenartikel Ammann, Dominic; Becker, Roland; Nehls, Irene Stability of ethyl glucuronide in hair reference materials after accelerated aging Two different hair reference materials, one produced from authentic hair displaying an ethyl glucuronide (EtG) content of about 25 pg/mg and one obtained by fortification of blank hair to an EtG level of 85 pg/mg were submitted to accelerated aging between 4 degrees C and 60 degrees C for periods between one and 24 months. Subsequently, the EtG content was determined in the aged samples and untreated reference samples stored at -22 degrees C under repeatability conditions following the so-called isochronous approach. The EtG content remained stable even at 40 degrees C for 24 months and at 60 degrees C over six months. This is in contrast to many organic analytes contained in trace concentrations in diverse matrices. A slight but significant increase of the recovered EtG in case of authentic hair samples having been exposed for 24 months between 4 degrees C and 60 degrees C may be due to a temperature-driven process that allows increased recoveries of the physiologically embedded EtG. Amsterdam [u.a.] Elsevier Ireland Ldt. 2015 Forensic science international 257 337 340 10.1016/j.forsciint.2015.09.015 2016-02-20