A 2D Sensitivity Encoded Silicon Photomultiplier (SeSP) for simultaneous high resolution PET/MR scanners

In this paper we present first results of a new detector concept called Sensitivity encoded Silicon Photomultiplier (SeSP) that has been invented in 2011. It combines the advantages of sensitivity encoding and SiPM technology without changing the manufacturing process of the devices. We show the capability to accurately identify all 4×4 crystals of a regular array with 2×4 (1D-SeSP) and 2×2 (2D-SeSP) readout channels. Even for these initial realizations, good energy resolution (<13% (1D) and <15.5% (2D)), timing resolution (average CRT of 468ps @ FWHM, 2D-SeSP), and stable operation are achieved

C25-modified rifamycin derivatives with improved activity against Mycobacterium abscessus.

Infections caused by Mycobacterium abscessus are difficult to treat due to its intrinsic resistance to most antibiotics. Formation of biofilms and the capacity of M. abscessus to survive inside host phagocytes further complicate eradication. Herein, we explored whether addition of a carbamate-linked group at the C25 position of rifamycin SV blocks enzymatic inactivation by ArrMab, an ADP-ribosyltransferase conferring resistance to rifampicin (RMP). Unlike RMP, 5j, a benzyl piperidine rifamycin derivative with a morpholino substituted C3 position and a naphthoquinone core, is not modified by purified ArrMab. Additionally, we show that the ArrMab D82 residue is essential for catalytic activity. Thermal profiling of ArrMab in the presence of 5j, RMP, or rifabutin shows that 5j does not bind to ArrMab. We found that the activity of 5j is comparable to amikacin against M. abscessus planktonic cultures and pellicles. Critically, 5j also exerts potent antimicrobial activity against M. abscessus in human macrophages and shows synergistic activity with amikacin and azithromycin