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Water miscible ionic liquids had various effects on the physiology of Clostridium sporogeneswhen tested as additives in culture media or reaction media for reduction of nitrobenzene. 2-Hydroxy ethyl trimethyl-ammonium dimethyl phosphate ([EtOHNMe3][Me2PO4]) and N,N-dimethylethanolammonium acetate (DMEAA) increased the growth rate of C. sporogenesby as much as 28%, suggesting that they were either metabolised or increased the availability of nutrients. By contrast, 1-butyl-3-methylimidazolium tetrafluoroborate ([BMim][BF4]) and AMMOENG™ 100 inhibited growth. Although 1-ethyl-3-methyl imidazolium ethylsulfate ([EMim][EtSO4]; 2% w/v) inhibited growth by 58%, it was sufficiently non-toxic to allow efficient reduction of nitrobenzene using harvested cells, providing aniline yields up to 79%. The high product yield with reactions in [EMim][EtSO4] represented a significant improvement over conventional solvents, since the yield was only 8% in aqueous ethanol (4% v/v) and 45% in a biphasic heptane/aqueous system (phase ratio 0.33). The ionic liquid appeared to suppress unproductive substrate consumption by an unknown mechanism [ABSTRACT FROM AUTHOR]

Abstract Objective  Positron emission tomography (PET) imaging at more than 1 h after 2-deoxy-2-[18F]fluoro-d-glucose (FDG) administration may result in less blood pool activity and possibly decreased normal FDG uptake in tissues such as liver. Lower normal background activity could be an important component of improved image contrast on delayed imaging. Increasing FDG uptake in normal organs, however, may mitigate the beneficial effects of blood pool clearance. The purpose of this study is to determine the normal tissue and blood pool FDG uptake at 1 and 3 h after injection. Subjects and methods  Ninety-nine patients with known or suspected malignancy referred for FDG-PET–computed tomography (CT) were retrospectively evaluated. PET imaging was performed at either 1 h (60 ± 15 min; n = 50) or at 3 h (180 ± 15 min; n = 49) after FDG administration. Normal tissue FDG uptake without involvement by malignancy or influenced by artifact (misregistration, “brown fat,” focal muscle uptake, focal atherosclerotic disease) was confirmed by inspection of both the PET and CT scans. Aortic blood pool, adipose tissue, bone marrow, cerebellum, liver, lungs, muscle, and spleen were quantitatively evaluated by CT-guided region of interest analysis in three contiguous slices. Mean standardized uptake values (SUVs) were analyzed using one-way analysis of variance. Results  Mean SUVs on the 3- versus 1-h images were significantly lower for aortic blood pool 13% (p p p p = 0.003), muscle 21% (p = 0.0004), and spleen 13% (p = 0.01). The liver and lung showed no significant differences (1%, p = 0.85; −2%, p = 0.62, respectively). Conclusions  On FDG imaging at 3 h compared to 1 h, significant changes were apparent, but the magnitude of changes was modest overall. Three-hour delayed imaging demonstrated significantly lower aortic blood pool and adipose tissue activity and significantly higher cerebellum, muscle, spleen, and bone marrow activity. Hepatic and lung activities were not significantly different. These results suggest that previously reported improvements in tumor image contrast with delayed imaging may be primarily due to cumulative FDG uptake within the tumor rather than reduction in normal background activity. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to an article about the U.S. national anthem in the April 2014 issue.