TY - CHAP A1 - Müller-Veggian, Mattea A1 - Kops, Elena Rota A1 - Quin, Peng A1 - Herzog, Hans T1 - MRI Based Attenuation Correction for Brain PET Images T2 - Advances in medical engineering / [3rd RPT - Remagener Physiktage together with the Second Scientific Workshop of Medical Robotics, Navigation and Visualization ... Remagen ... 7.-9. März 2007]. Thorsten M. Buzug (ed.) Part 1. N2 - This work describes a procedure to yield attenuation maps from MR images which are used for the absorption correction (AC) of brain PET data. Such an approach could be mandatory for future combined PET and MRI scanners, which probably do not include a transmission facility. T1-weighted MR images were segmented into brain tissue, bone, soft tissue, and sinus; attenuation coefficients corresponding to elemental composition and density as well as to 511 keV photon energy were respectively assigned. Attenuation maps containing up to four compartments were created and forward projected into sinograms with attenuation factors which then were used for AC during reconstruction of FDG-PET data. The commonly used AC based on a radioactive (68Ge) transmission scan served as reference. The reconstructed radioactivity values obtained with the MRI-based AC were about 20% lower than those obtained with PET-based AC if the skull was not taken into account. Considering the skull the difference was still about 10%. Our investigations demonstrate the feasibility of a MRI-based AC, but revealed also the necessity of a satisfying delineation of bone thickness which tends to be underestimated in our first approach of T1-weighted MR image segmentation. Y1 - 2007 SN - 978-3-540-68763-4 U6 - https://doi.org/10.1007/978-3-540-68764-1_15 N1 - Springer proceedings in physics ; 114 SP - 93 EP - 97 PB - Springer CY - Berlin ER - TY - JOUR A1 - Müller-Veggian, Mattea A1 - Moro, D. A1 - Ferreti, A. A1 - Colautti, P. T1 - The new articulated twin mini TEPC JF - Annual Report 2006 / Istituto Nazionale di Fisica Nucleare / Laboratori Nazionali Y1 - 2006 SP - 273 CY - Legnaro ER - TY - JOUR A1 - Selmer, Thorsten A1 - Kim, Jihoe A1 - Darley, Daniel A1 - Buckel, Wolfgang T1 - Characterization of (R)-2-hydroxyisocaproate dehydrogenase and a family III coenzyme A transferase involved in reduction of L-leucine to isocaproate by Clostridium difficile / Kim, J. ; Darley, D. ; Selmer, T. ; Buckel, W. JF - Applied and Environmental Microbiology. 72 (2006), H. 9 Y1 - 2006 SN - 0099-2240 N1 - PMID: 16957230 SP - 6062 EP - 6069 ER - TY - JOUR A1 - Selmer, Thorsten A1 - Yu, Lihua A1 - Blaser, Martin A1 - Andrei, Paula I. T1 - 4-Hydroxyphenylacetate decarboxylases: properties of a novel subclass of glycyl radical enzyme systems / Yu, L. ; Blaser, M. ; Andrei, PI. ; Pierik, AJ. Selmer, T. JF - Biochemistry. 31 (2006), H. 45 Y1 - 2006 N1 - PMID: 16878993 SP - 9584 EP - 9592 ER - TY - JOUR A1 - Selmer, Thorsten A1 - Pierik, Antonio J. A1 - Heider, Johann T1 - New glycyl radical enzymes catalysing key metabolic steps in anaerobic bacteria JF - Biological Chemistry. 386 (2005), H. 10 Y1 - 2005 SN - 1431-6730 SP - 981 EP - 988 ER - TY - JOUR A1 - Selmer, Thorsten A1 - Achebach, Stephanie A1 - Unden, Gottfried T1 - Properties and significance of apoFNR as a second form of air-inactivated [4Fe-4S]·FNR of Escherichia coli / Achebach, S. ; Selmer, T. ; Unden, G. JF - The FEBS Journal. 272 (2005), H. 16 Y1 - 2005 SN - 1742-464X SP - 4260 EP - 4269 ER - TY - JOUR A1 - Selmer, Thorsten A1 - Hermann, Gloria A1 - Jessen, Holly A1 - Gokarn, Ravi R. T1 - Two beta-alanyl-CoA:ammonia lyases in Clostridium propionicum / Herrmann , G. ; Selmer, T. ; Jessen, HJ. ; Gokarn, RR. ; Selifonova, O. ; Gort , SJ. ; , Buckel, W. JF - The FEBS Journal. 272 (2005), H. 3 Y1 - 2005 SN - 1742-464X SP - 813 EP - 821 ER - TY - JOUR A1 - Selmer, Thorsten A1 - Andrei, Paula I. A1 - Pierik, Antonio J. A1 - Zauner, Stefan T1 - Subunit composition of the glycyl radical enzyme p-hydroxyphenylacetate decarboxylase. A small subunit, HpdC, is essential for catalytic activity / Andrei, PI. ; Pierik, AJ. ; Zauner , S. ; Andrei-Selmer, LC. ; Selmer, T. JF - European Journal of Biochemistry. 271 (2004), H. 11 Y1 - 2004 SN - 0014-2956 SP - 2225 EP - 2230 ER - TY - JOUR A1 - Selmer, Thorsten A1 - Hetzel, Marc A1 - Brock, Matthias A1 - Pierik, Antonio J. T1 - Acryloyl-CoA reductase from Clostridium propionicum. An enzyme complex of propionyl-CoA dehydrogenase and electron-transferring flavoprotein / Hetzel, Marc ; Brock, Matthias ; Selmer, Thorsten, Pierik, Antonio J. ; Golding, Bernard T. ; Buckel, Wolfgang JF - European Journal of Biochemistry. 270 (2003), H. 5 Y1 - 2003 SN - 0014-2956 SP - 902 EP - 910 ER - TY - JOUR A1 - Selmer, Thorsten A1 - Willanzheimer, Angela A1 - Hetzel, Marc T1 - Propionate CoA-transferase from Clostridium propionicum. Cloning of the gene and identification of glutamate 324 at the active site JF - European Journal of Biochemistry. 269 (2002), H. 1 Y1 - 2002 SN - 0014-2956 SP - 372 EP - 380 ER - TY - JOUR A1 - Selmer, Thorsten A1 - Andrei, Paula I. T1 - p-Hydroxyphenylacetate decarboxylase from Clostridium difficile. A novel glycyl radical enzyme catalysing the formation of p-cresol JF - European Journal of Biochemistry. 268 (2001), H. 5 Y1 - 2001 SN - 0014-2956 SP - 1363 EP - 1372 ER - TY - JOUR A1 - Selmer, Thorsten A1 - Jennemann, Richard A1 - Bauer, Bernhard L. A1 - Bertalanffy, Helmut T1 - Novel glycoinositolphosphosphingolipids, basidiolipids, from Agaricus / Jennemann, Richard ; Bauer, Bernhard, L. ; Bertalanffy, Helmut ; Geyer, Rudolf ; Gschwind, Ruth, M. ; Selmer, Thorsten ; Wiegandt, Herbert JF - European Journal of Biochemistry. 259 (1999), H. 1-2 Y1 - 1999 SN - 0014-2956 SP - 331 EP - 338 ER - TY - JOUR A1 - Selmer, Thorsten A1 - Kahnt, Jörg A1 - Goubeaud, Marcel A1 - Shima, Seigo T1 - The biosynthesis of methylated amino acids in the active site region of methyl-coenzyme M reductase / Selmer, Thorsten ; Kahnt, Jörg ; Goubeaud, Marcel ; Shima, Seigo ; Grabarse, Wolfgang ; Ermler, Ulrich ; Thauer, Rudolf K. JF - Journal of Biological Chemistry. 275 (2000), H. 6 Y1 - 2000 SN - 1083-351X SP - 3775 EP - 3760 ER - TY - JOUR A1 - Selmer, Thorsten A1 - Brüser, Thomas A1 - Dahl, Christiane T1 - ADP Sulfurylase" from Thiobacillus denitrificans Is an Adenylylsulfate:Phosphate Adenylyltransferase and Belongs to a New Family of Nucleotidyltransferases / Brüser, Thomas ; Selmer, Thorsten ; Dahl, Christiane JF - Journal of Biological Chemistry. 275 (2000), H. 3 Y1 - 2000 SN - 1083-351X SP - 1691 EP - 1690 ER - TY - JOUR A1 - Selmer, Thorsten A1 - Buckel, Wolfgang T1 - Oxygen Exchange between Acetate and the Catalytic Glutamate Residue in Glutaconate CoA-transferase from Acidaminococcus fermentans. IMPLICATIONS FOR THE MECHANISM OF CoA-ESTER HYDROLYSIS JF - Journal of Biological Chemistry. 274 (1999), H. 30 Y1 - 1999 SN - 1083-351X SP - 20772 EP - 20778 ER - TY - JOUR A1 - Selmer, Thorsten A1 - Recksiek, Michael A1 - Dierks, Thomas A1 - Schmidt, Bernhard T1 - Sulfatases, Trapping of the Sulfated Enzyme Intermediate by Substituting the Active Site Formylglycine / Recksiek, Michael ; Selmer, Thorsten ; Dierks, Thomas ; Schmidt, Bernhard ; Figura, Kurt von JF - Journal of Biological Chemistry. 273 (1998), H. 11 Y1 - 1998 SN - 1083-351X SP - 6096 EP - 6103 ER - TY - JOUR A1 - Selmer, Thorsten A1 - Miech, Claudia A1 - Dierks, Thomas A1 - Figura, Kurt von T1 - Arylsulfatase from Klebsiella pneumoniae Carries a Formylglycine Generated from a Serine / Miech, Claudia ; Dierks, Thomas ; Selmer, Thorsten ; Figura, Kurt von ; Schmidt, Bernd JF - Journal of Biological Chemistry. 273 (1998), H. 9 Y1 - 1998 SN - 1083-351X SP - 4835 EP - 4837 ER - TY - JOUR A1 - Selmer, Thorsten A1 - Sommerlade, Hans-Jörg A1 - Ingendoh, Arnd A1 - Gieselmann, Volkmar T1 - Glycosylation and phosphorylation of arylsulfatase A / Sommerlade, Hans-Jörg. ; Selmer, Thomas. ; Ingendoh, Arnd ; Gieselmann, Volkmar ; Figura, Kurt von ; Neifer, Klaus ; Schmidt, Bernhard JF - Journal of Biological Chemistry. 269 (1994), H. 33 Y1 - 1994 SN - 1083-351X SP - 20977 EP - 20981 ER - TY - JOUR A1 - Selmer, Thorsten A1 - Jennemann, Richard A1 - Bauer, Bernhard L. A1 - Bertalanffy, Helmut T1 - Basidiolipids from Agaricus are novel immune adjuvants / Jennemann, R. ; Bauer, BL. ; Bertalanffy, H. ; Selmer, T. ; Wiegandt, H. JF - Immunobiology. 200 (1999), H. 2 Y1 - 1999 SN - 0171-2985 N1 - PMID: 10416134 SP - 277 EP - 289 ER - TY - JOUR A1 - Selmer, Thorsten A1 - Figura, Kurt von A1 - Schmidt, Bernhard A1 - Dierks, T. T1 - A novel protein modification generating an aldehyde group in sulfatases: its role in catalysis and disease / Figura, Kurt von ; Schmidt, Bernhard ; Selmer, Thorsten ; Dierks, Thomas JF - Bioessays. 20 (1998), H. 6 Y1 - 1998 SN - 1521-1878 SP - 505 EP - 510 ER -