TY - JOUR A1 - Scharkoi, O. A1 - Becker, Roland A1 - Esslinger, Susanne A1 - Weber, M. A1 - Nehls, Irene T1 - Predicting sites of cytochrome P450-mediated hydroxylation applied to CYP3A4 and hexabromocyclododecane N2 - 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. KW - Predicting sites of metabolism KW - Cytochrome P450 KW - Hydroxylation KW - Metabolism of HBCD PY - 2015 U6 - https://doi.org/10.1080/08927022.2014.898845 SN - 0892-7022 SN - 1029-0435 VL - 41 IS - 7 SP - 538 EP - 546 PB - Gordon and Breach CY - New York, NY AN - OPUS4-30492 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schallschmidt, Kristin A1 - Becker, Roland A1 - Zwaka, H. A1 - Menzel, R. A1 - Johnen, D. A1 - Fischer-Tenhagen, C. A1 - Rolff, J. A1 - Nehls, Irene T1 - In vitro cultured lung cancer cells are not suitable for animal-based breath biomarker detection N2 - 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. KW - A549 KW - Honey bees KW - Odour discrimination task KW - Sniffer dogs KW - Solid phase microextraction KW - Volatile organic compounds KW - Volatilome PY - 2015 U6 - https://doi.org/10.1088/1752-7155/9/2/027103 SN - 1752-7155 SN - 1752-7163 VL - 9 IS - 2 SP - 027103-1 EP - 027103-10 PB - IOP CY - Bristol AN - OPUS4-34161 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Nehls, Irene A1 - Schallschmidt, Kristin A1 - Becker, Roland A1 - Fischer-Tenhagen, C. A1 - Johnen, D. A1 - Leschber, G. A1 - Frese, S. A1 - Neudecker, J. A1 - Walles, T. ED - Schüler, C. ED - Püschel, K. T1 - BIOAIR - Ein interdisziplinäres Projekt zur Bestimmung von Krebsmarkern in der Atemluft N2 - 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. PY - 2015 SN - 978-3-8300-8763-2 N1 - Serientitel: Forschungsergebnisse aus dem Institut für Rechtsmedizin der Universität Hamburg – Series title: Forschungsergebnisse aus dem Institut für Rechtsmedizin der Universität Hamburg VL - 30 SP - 93 EP - 101 PB - Dr. Kovac AN - OPUS4-33165 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Becker, Roland A1 - Dorgerloh, Ute A1 - Nehls, Irene T1 - Analysis of volatile and semi-volatile components in hydrochar: prospects and challenges T2 - International Biochar Symposium 2015 Biochar - Contribution to Sustainable Agriculture CY - Potsdam DA - 2015-05-28 PY - 2015 AN - OPUS4-33741 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Becker, Roland A1 - Ammann, Dominic A1 - Mönch, Bettina A1 - Nehls, Irene T1 - Chemische Analytik in der Forensik: Der Alkoholkonsummarker Ethylglucuronid T2 - ANAKON 2015 CY - Graz (Österreich) DA - 2015-03-23 PY - 2015 AN - OPUS4-32828 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Sauer, Andreas A1 - Scharf, Holger A1 - Becker, Roland T1 - Bericht zum 21. BAM-Ringversuch "Altlasten" N2 - Präsentation der Ergebnisse eines Ringversuchs zur Kompetenzbewertung von Prüflaboratorien auf dem Gebiet der anorganischen und organischen Bodenanalytik. KW - Eignungsprüfung KW - Boden KW - PAK KW - MKW KW - Spurenelemente KW - Gesamtcyanid KW - Proficiency testing KW - Soil KW - PAH KW - TPH KW - Trace elements KW - Total cyanide PY - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-355586 SP - 1 EP - 234 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-35558 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Becker, Roland A1 - Schallschmidt, Kristin A1 - Nehls, Irene A1 - Johnen, D. A1 - Fischer-Tenhagen, C. T1 - Odour reference materials and training concepts for sniffer dogs T2 - International Association of Breath Research Summit 2015 CY - Wien (Österreich) DA - 2015-09-14 PY - 2015 AN - OPUS4-33981 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Becker, Roland A1 - Schallschmidt, Kristin A1 - Nehls, Irene A1 - Johnen, D. A1 - Fischer-Tenhagen, C. T1 - Odour reference material and training concepts for sniffer dogs T2 - International Conference on Medical Bio-Detection CY - Cambridge (England) DA - 2015-09-15 PY - 2015 AN - OPUS4-33984 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schallschmidt, Kristin A1 - Becker, Roland A1 - Jung, Christian A1 - Rolff, J. A1 - Fichtner, I. T1 - Investigation of cell culture volatilomes using solid phase micro extraction: options and pitfalls exemplified with adenocarcinoma cell lines N2 - 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. KW - A549 KW - Lung cancer cell culture KW - GC–MS KW - SPME KW - VOC KW - Volatilome KW - Alcohol marker KW - Micropulverization KW - HPLC-MS/MS KW - Fortification KW - Long term stability PY - 2015 U6 - https://doi.org/10.1016/j.jchromb.2015.10.004 SN - 0378-4347 SN - 1570-0232 SN - 1387-2273 SN - 1873-376X VL - 1006 SP - 158 EP - 166 PB - Elsevier B.V. CY - Amsterdam [u.a.] AN - OPUS4-34991 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ammann, Dominic A1 - Becker, Roland A1 - Nehls, Irene T1 - Stability of ethyl glucuronide in hair reference materials after accelerated aging N2 - 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. KW - Alcohol marker KW - Micropulverization KW - HPLC-MS/MS KW - Fortification KW - Long term stability PY - 2015 U6 - https://doi.org/10.1016/j.forsciint.2015.09.015 SN - 0379-0738 SN - 1872-6283 VL - 257 SP - 337 EP - 340 PB - Elsevier Ireland Ldt. CY - Amsterdam [u.a.] AN - OPUS4-34940 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -