Single-cell analysis: visualizing pharmaceutical and metabolite uptake in cells with label-free 3D mass spectrometry imaging

Detecting metabolites and parent compound within a cell type is now a priority for pharmaceutical development. In this context, three-dimensional secondary ion mass spectrometry (SIMS) imaging was used to investigate the cellular uptake of the antiarrhythmic agent amiodarone, a phospholipidosis-inducing pharmaceutical compound. The high lateral resolution and 3D imaging capabilities of SIMS combined with the multiplex capabilities of ToF mass spectrometric detection allows for the visualization of pharmaceutical compound and metabolites in single cells. The intact, unlabeled drug compound was successfully detected at therapeutic dosages in macrophages (cell line: NR8383). Chemical information from endogenous biomolecules was used to correlate drug distributions with morphological features. From this spatial analysis, amiodarone was detected throughout the cell with the majority of the compound found in the membrane and subsurface regions and absent in the nuclear regions. Similar results were obtained when the macrophages were doped with amiodarone metabolite, desethylamiodarone. The FWHM lateral resolution measured across an intracellular interface in a high lateral resolution ion images was approximately 550 nm. Overall, this approach provides the basis for studying cellular uptake of pharmaceutical compounds and their metabolites on the single cell level

Für den Erfolg entscheidend: metallfreie zirkoniumdioxidbasierte Rekonstruktionen - Bearbeitungsschritte zum Erfolg

Metallfreie Rekonstruktionen setzten sich aufgrund der guten Ästhetik, Biokompatibilität und der guten mechanischen Eigenschaften immer stärker durch. Zirkoniumdioxid als Gerüstmaterial wird mittlerweile fast in jedem Labor bearbeitet. Leider wird immer häufiger festgestellt, dass dieses Material eine „Sonderbearbeitung“ benötigt und sich nicht wie die herkömmlichen VMK-Rekonstruktionen lässt. In dem vorliegenden Beitrag werden die mechanischen Eigenschaften und die Verarbeitungsarten von Zirkoniumdioxidrekonstruktionen mit VMK-Versorgung gegenübergestellt und diskutiert

A Gag peptide encompassing B- and T-cell epitopes of the caprine arthritis encephalitis virus functions as modular carrier peptide

Short synthetic peptides are important tools in biomedical research permitting to generate hapten specific polyclonal sera for analytical purposes or functional studies. In this paper we provide proof of principle that a peptide located in a highly conserved portion of the Gag protein of the caprine arthritis encephalitis virus and carrying an immunodominant T helper cell epitope functions as an efficient carrier peptide, mediating a strong antibody response to a peptidic hapten encompassing a well-characterized B cell epitope of Env. The carrier and hapten peptides were collinearly synthesized permutating their molecular arrangement. While the antibody response to the hapten was similar for both constructs, the antibody response to a B cell epitope overlapping the T helper cell epitope of the Gag carrier peptide was considerably different. This permits a modular use of the carrier peptide to generate antibody directed exclusively to the hapten peptide or a strong humoral response to both carrier- and hapten-peptide. Finally, we have mapped the epitopes involved in this polarized antibody response and discussed the potential immunological implications

Quantifying rates of detachment faulting and erosion in the central Menderes Massif (western Turkey) by thermochronology and cosmogenic 10

Exhumation of rocks in extensional tectonic settings results from a combination of normal faulting and erosion but the relative contribution of these processes has rarely been quantified. Here we present new low-temperature thermochronological data and the first Be-10-based catchment-wide erosion rates from the Boz Dag region in the central Menderes Massif, which has experienced NNE-SSW extension since the Miocene. The slip rate of the shallow-dipping Gediz detachment fault, which defines the northern flank of the Boz Dag block, is 4.3 (+3.0/-1.2) mm a(-1), as constrained by zircon (U-Th)/He ages of c. 4-2 Ma in the footwall. Apatite and zircon (U-Th)/He and fission-track ages from the northern flank of the Boz Dag block yield exhumation rates of 0.6-2 km Ma(-1) beneath the Gediz detachment, whereas those on the southern flank are only 0.2-0.6 km Ma(-1). Erosion of catchments on the northern and southern flanks proceeds at rates of 80-180 and 330-460 mm ka(-1), respectively. This marked contrast is a combined effect of the topographic asymmetry of the Boz Dag block and differences in rock erodibility. If these erosion rates persisted in the past, rock exhumation on the northern flank occurred predominantly by tectonic denudation, whereas rocks on the southern flank were mainly exhumed by erosion