Revealing Silver Nanoparticle Uptake by Macrophages Using SR-μXRF and LA-ICP-MS.

To better study the impact of nanoparticles on both and models, tissue distribution and cellular doses need to be described more closely. Here silver nanoparticles were visualized in alveolar macrophages by means of synchrotron radiation micro X-ray fluorescence spectroscopy (SR-μXRF) with high spatial resolution of 3 × 3 μm. For the spatial allocation of silver signals to cells and tissue structures, additional elemental labeling was carried out by staining with eosin, which binds to protein and can be detected as bromine signal with SR-μXRF.

A Ribonucleoprotein Supercomplex Involved in trans-Splicing of Organelle Group II Introns.

In the chloroplast of the green alga Chlamydomonas reinhardtii, two discontinuous group II introns, psaA-i1 and psaA-i2, splice in trans, and thus their excision process resembles the nuclear spliceosomal splicing pathway. Here, we address the question whether fragmentation of trans-acting RNAs is accompanied by the formation of a chloroplast spliceosome-like machinery. Using a combination of liquid chromatography-mass spectrometry (LC-MS), size exclusion chromatography, and quantitative RT-PCR, we provide the first characterization of a high molecular weight ribonucleoprotein apparatus participating in psaA mRNA splicing.

A pioneer protein is part of a large complex involved in trans-splicing of a group II intron in the chloroplast of Chlamydomonas reinhardtii.

Splicing of organellar introns requires the activity of numerous nucleus-encoded factors. In the chloroplast of Chlamydomonas reinhardtii, maturation of psaA mRNA encoding photosystem I subunit A involves two steps of trans-splicing. The exons, located on three separate transcripts, are flanked by sequences that fold to form the conserved structures of two group II introns.

Quantitative imaging of platinum based on laser ablation-inductively coupled plasma-mass spectrometry to investigate toxic side effects of cisplatin.

This work presents a quantitative bioimaging method for platinum based on laser ablation-inductively coupled plasma-mass spectrometry and its application for a biomedical study concerning toxic side effects of cisplatin. To trace the histopathology back to cisplatin, platinum was localized and quantified in major functional units of testicle, cochlea, kidney, nerve and brain sections from cisplatin treated mice. The direct consideration of the histology enables precise interpretation of the Pt images and the novel quantitative evaluation approach allows significantly more precise investigations than the pure image.

Elemental bioimaging of thulium in mouse tissues by laser ablation-ICPMS as a complementary method to heteronuclear proton magnetic resonance imaging for cell tracking experiments.

Due to the fact that cellular therapies are increasingly finding application in clinical trials and promise success by treatment of fatal diseases, monitoring strategies to investigate the delivery of the therapeutic cells to the target organs are getting more and more into the focus of modern in vivo imaging methods. In order to monitor the distribution of the respective cells, they can be labeled with lanthanide complexes such as thulium-1,4,7,10-tetraazacyclodoecane-α,α,α,α-tetramethyl-1,4,7,10-tetraacetic acid (Tm(DOTMA)). In this study, experiments on a mouse model with two different cell types, namely, tumor cells and macrophages labeled with Tm(DOTMA), were performed.