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Thomas Volz

Publications and source records attributed to Thomas Volz.

4 recordsLinked to original sources
PubMed2004

Observation of molecules produced from a Bose-Einstein condensate.

Molecules are created from a Bose-Einstein condensate of atomic 87Rb using a Feshbach resonance. A Stern-Gerlach field is applied, in order to spatially separate the molecules from the remaining atoms. For detection, the molecules are converted back into atoms, again using the Feshbach resonance. The measured position of the molecules yields their magnetic moment. This quantity strongly depends on the magnetic field, thus revealing an avoided crossing of two bound states at a field value slightly below the Feshbach resonance. This avoided crossing is exploited to trap the molecules in one dimension.

Journal Article↗
PubMed2004

Determination of the peptide binding motif and high-affinity ligands for HLA-DQ4 using synthetic peptide libraries.

Juvenile idiopathic arthritis (JIA) is considered to be an autoimmune disease. Various human leukocyte antigen (HLA) associations for different subgroups of this heterogeneous disease have been found. For early-onset pauciarticular arthritis (now oligoarthritic JIA), a strong association with the HLA class II haplotype DQA1*0401/DQB1*0402 (DQ4) has been described. We determined the peptide-binding specificities of this HLA-DQ molecule by screening a synthetic acetylated nonapeptide amide library with one defined and eight random sequence positions. A characteristic binding motif could be deduced. By use of these data, we designed defined specific nonapeptides and identified high-affinity ligands binding to HLA-DQ4. The peptide binding motif of HLA-DQ4 is very similar to the motif of HLA-DQ7, also associated with oligoarthritic JIA. It is, however, different from binding motifs of neutral or protective HLA-DQ molecules. Our results further support the idea of differential peptide presentation in the pathogenesis of oligoarthritic JIA.

Amino Acid Motifs↗