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The Tabby cat locus maps to feline chromosome B1.
The Tabby markings of the domestic cat are unique coat patterns for which no causative candidate gene has been inferred from other mammals. In this study, a genome scan was performed on a large pedigree of cats that segregated for Tabby coat markings, specifically for the Abyssinian (Ta-) and blotched (tbtb) phenotypes. There was linkage between the Tabby locus and eight markers on cat chromosome B1. The most significant linkage was between marker FCA700 and Tabby (Z = 7.56, theta = 0.03). Two additional markers in the region supported linkage, although not with significant LOD scores. Pairwise analysis of the markers supported the published genetic map of the cat, although additional meioses are required to refine the region. The linked markers cover a 17-cM region and flank an evolutionary breakpoint, suggesting that the Tabby gene has a homologue on either human chromosome 4 or 8. Alternatively, Tabby could be a unique locus in cats
Benchmark problems for robust control design
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76996/1/AIAA-20949-475.pd
Selective AKR1C3 inhibitors do not recapitulate the anti-leukaemic activities of the pan-AKR1C inhibitor medroxyprogesterone acetate
Background: We and others have identified the aldo-keto reductase AKR1C3 as a potential drug target in prostate cancer, breast cancer and leukaemia. As a consequence, significant effort is being invested in the development of AKR1C3-selective inhibitors. Methods: We report the screening of an in-house drug library to identify known drugs that selectively inhibit AKR1C3 over the closely related isoforms AKR1C1, 1C2 and 1C4. This screen initially identified tetracycline as a potential AKR1C3-selective inhibitor. However, mass spectrometry and nuclear magnetic resonance studies identified that the active agent was a novel breakdown product (4-methyl(de-dimethylamine)-tetracycline (4-MDDT)). Results: We demonstrate that, although 4-MDDT enters AML cells and inhibits their AKR1C3 activity, it does not recapitulate the anti-leukaemic actions of the pan-AKR1C inhibitor medroxyprogesterone acetate (MPA). Screens of the NCI diversity set and an independently curated small-molecule library identified several additional AKR1C3-selective inhibitors, none of which had the expected anti-leukaemic activity. However, a pan AKR1C, also identified in the NCI diversity set faithfully recapitulated the actions of MPA. Conclusions: In summary, we have identified a novel tetracycline-derived product that provides an excellent lead structure with proven drug-like qualities for the development of AKR1C3 inhibitors. However, our findings suggest that, at least in leukaemia, selective inhibition of AKR1C3 is insufficient to elicit an anticancer effect and that multiple AKR1C inhibition may be required
Exposure assessment of process-related contaminants in food by biomarker monitoring
Exposure assessment is a fundamental part of the risk assessment paradigm, but can often present a number of challenges and uncertainties. This is especially the case for process contaminants formed during the processing, e.g. heating of food, since they are in part highly reactive and/or volatile, thus making exposure assessment by analysing contents in food unreliable. New approaches are therefore required to accurately assess consumer exposure and thus better inform the risk assessment. Such novel approaches may include the use of biomarkers, physiologically based kinetic (PBK) modelling-facilitated reverse dosimetry, and/or duplicate diet studies. This review focuses on the state of the art with respect to the use of biomarkers of exposure for the process contaminants acrylamide, 3-MCPD esters, glycidyl esters, furan and acrolein. From the overview presented, it becomes clear that the field of assessing human exposure to process-related contaminants in food by biomarker monitoring is promising and strongly developing. The current state of the art as well as the existing data gaps and challenges for the future were defined. They include (1) using PBK modelling and duplicate diet studies to establish, preferably in humans, correlations between external exposure and biomarkers; (2) elucidation of the possible endogenous formation of the process-related contaminants and the resulting biomarker levels; (3) the influence of inter-individual variations and how to include that in the biomarker-based exposure predictions; (4) the correction for confounding factors; (5) the value of the different biomarkers in relation to exposure scenario’s and risk assessment, and (6) the possibilities of novel methodologies. In spite of these challenges it can be concluded that biomarker-based exposure assessment provides a unique opportunity to more accurately assess consumer exposure to process-related contaminants in food and thus to better inform risk assessment
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