ABSTRACT:Contrast-enhancing magnetic resonance imaging with the liverspecific agent gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) has been shown to improve the detection rate of focal lesions. There is evidence from preclinical studies that multidrug organic anion transporters are involved in hepatic uptake of Gd-EOB-DTPA. Therefore, we evaluated affinity of the contrast agent to human organic anion-transporting polypeptides (OATP1B1, OATP1B3, OATP2B1) and to the Na The uptake by OATP2B1 was not different from the vector control.In conclusion, Gd-EOB-DTPA is a substrate of the liver-specific OATP1B1, OATP1B3, and NTCP.

Photo-ionization detectors (PIDs) are suited ideally to be combined with gas chromatographs (GCs). Without a GC, a PID can be used as a cheap unspecific sensor for noxious substances in the air. In this case, the unpredictable slow offset drift of the device leads to a significantly worsened detection limit. The dependence of the sensitivity on ambient humidity further deteriorates the accuracy, so that the usability of a classical PID without GC in practice is highly limited. We present a new PID design that eliminates the offset and thus offset drift problems and reduces the cross-sensitivity to humidity. It is based on an additional grid that allows modulation of the ion flow in a part of the ionization chamber. This modified PID exhibits a 20 times improved detection limit and a reduction of the cross-sensitivity to humidity from 58% of the signal to 10% of the signal. Further reduction is possible.