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31.
Haemers T Wiesner J Giessmann D Verbrugghen T Hillaert U Ortmann R Jomaa H Link A Schlitzer M Van Calenbergh S 《Bioorganic & medicinal chemistry》2008,16(6):3361-3371
To expand the structure-activity relationships of fosmidomycin and FR900098, two potent antimalarials interfering with the MEP-pathway, we decided to replace a methylene group in beta-position of the phosphonate moiety of these leads by an oxygen atom. beta-oxa-FR900098 (11) proved equally active as the parent compound. When applied to 4-[hydroxyl(methyl)amino]-4-oxobutyl phosphonic acid, featuring a hydroxamate instead of the retrohydroxamate moiety, a beta-oxa modification yielded a derivative (13) with superior activity against the Plasmodium falciparum 3D7 strain than fosmidomycin, while a gamma-oxa modification resulted in less active derivatives. A bis(pivaloyloxymethyl)ester of phosphonate 13 proved twice as active in inhibiting cultured parasites as a similar prodrug of FR900098. 相似文献
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33.
Hanne N. Rasmussen Bjarke Veierskov Jens Hansen-Møller Rikke Nørbæk Ulrik Bräuner Nielsen 《Journal of Plant Growth Regulation》2009,28(2):154-166
Conifer trees are routinely manipulated hormonally to increase flowering, branching, or adjust crown shape for production
purposes. This survey of internal cytokinin levels provides a background for such treatments in Abies nordmanniana, a tree of great economic interest. Reference points in the crown and root system were sampled destructively in 4- and 6-year-old
trees and analyzed for a range of cytokinins by LC-MS/MS. No seasonal patterns were detected in the root samples, and a major
portion of cytokinin was in conjugated forms. Dramatic and consistent seasonal changes occurred in the crown, at levels 17–65 times
higher than in the root. Predominant among crown cytokinins was ZR, except in the needles where IPR was also prominent. Within
the crown, cytokinin profiles in different organs differed consistently. The leader bud showed a pronounced mid-June minimum,
and a maximum later in summer. Subapical buds showed the same June minimum but peaked in mid autumn at a much lower level.
Maxima in these buds were preceded by peaks in the subapical stem. Parallel patterns were observed in homologous tissues on
branches.This pattern is consistent with two surges beginning in the uppermost stem tissues leading to subsequent accumulation
or stimulated production within the buds. Strong differential hormonal profiles between adjacent buds with different fates
agree with recent evidence of localized cytokinin production. The data suggest a reduced role of root-derived cytokinins in
crown development. Practical cytokinin treatments for crown-shape regulation require close attention to dosage as well as
precise timing and positioning. 相似文献
34.
The intention of this review is to provide an overview of current methodologies employed in the rapidly developing field of ocular proteomics with emphasis on sample preparation, two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and mass spectrometry (MS). Appropriate sample preparation for the diverse range of cells and tissues of the eye is essential to ensure reliable results. Current methods of protein staining for 2D-PAGE, protein labelling for two-dimensional difference gel electrophoresis, gel-based expression analysis and protein identification by MS are summarised. The uses of gel-free MS-based strategies (MuDPIT, iTRAQ, ICAT and SILAC) are also discussed. Proteomic technologies promise to shed new light onto ocular disease processes that could lead to the discovery of strong novel biomarkers and therapeutic targets useful in many ophthalmic conditions. 相似文献
35.
Synthesis and biological evaluation of novel PDMP analogues 总被引:1,自引:0,他引:1
Hillaert U Boldin-Adamsky S Rozenski J Busson R Futerman AH Van Calenbergh S 《Bioorganic & medicinal chemistry》2006,14(15):5273-5284
A new series of hybrid PDMP analogues, based both on PDMP and styryl analogues of natural ceramide, has been synthesized from D-serine. The synthetic route was developed such that future introduction of different aryl groups is straightforward. Biological evaluation, both in vitro on rat liver Golgi fractions as well as in HEK-293 and COS-7 cells, revealed two lead compounds with comparable inhibitory potency as PDMP, which could be elaborated to more potent inhibitors. 相似文献
36.
Naveen Kumar Kadri Goutam Sahana Carole Charlier Terhi Iso-Touru Bernt Guldbrandtsen Latifa Karim Ulrik Sander Nielsen Frank Panitz Gert Pedersen Aamand Nina Schulman Michel Georges Johanna Vilkki Mogens Sand? Lund Tom Druet 《PLoS genetics》2014,10(1)
In dairy cattle, the widespread use of artificial insemination has resulted in increased selection intensity, which has led to spectacular increase in productivity. However, cow fertility has concomitantly severely declined. It is generally assumed that this reduction is primarily due to the negative energy balance of high-producing cows at the peak of lactation. We herein describe the fine-mapping of a major fertility QTL in Nordic Red cattle, and identify a 660-kb deletion encompassing four genes as the causative variant. We show that the deletion is a recessive embryonically lethal mutation. This probably results from the loss of RNASEH2B, which is known to cause embryonic death in mice. Despite its dramatic effect on fertility, 13%, 23% and 32% of the animals carry the deletion in Danish, Swedish and Finnish Red Cattle, respectively. To explain this, we searched for favorable effects on other traits and found that the deletion has strong positive effects on milk yield. This study demonstrates that embryonic lethal mutations account for a non-negligible fraction of the decline in fertility of domestic cattle, and that associated positive effects on milk yield may account for part of the negative genetic correlation. Our study adds to the evidence that structural variants contribute to animal phenotypic variation, and that balancing selection might be more common in livestock species than previously appreciated. 相似文献
37.
The relationship between body dry weight (W) and shell length (L) of blue mussels, Mytilus edulis, can be expressed by the condition index (CI = W/L 3) which varies from population to population and during the year. Here, we examine the influence of CI on the relationships between maximum filtration rate (F, l h?1), W (g), and L (mm) as described by the equations: F W = aW b and F L = cL d , respectively. This is done by using available and new experimental laboratory data on M. edulis obtained by members of the same research team using different methods and controlled diets of cultivated algal cells. For all data, it was found that F W = 6.773W 0.678 and F L = 0.00135L 2.088 which are very similar to equations for mussels with ‘medium condition’ (CI = 4–6 mg cm?3): F W = 6.567W 0.681 and F L = 0.00150L 2.051, with b- and d-values within a few percent of the theoretically expected of 2/3 and 2, respectively. Further, based on the present data, we propose a correction factor expressed by the empirical relation F W /F L = 0.3562CI2/3 which implies that F W tends to underestimate the actual filtration rate (F L ) when CI < 4.70 and to overestimate the filtration rate when CI > 4.70. 相似文献
38.
Karin Wolffhechel Jens Fagertun Ulrik Plesner Jacobsen Wiktor Majewski Astrid Sofie Hemmingsen Catrine Lohmann Larsen Sofie Katrine Lorentzen Hanne Jarmer 《PloS one》2014,9(9)
Appearance is known to influence social interactions, which in turn could potentially influence personality development. In this study we focus on discovering the relationship between self-reported personality traits, first impressions and facial characteristics. The results reveal that several personality traits can be read above chance from a face, and that facial features influence first impressions. Despite the former, our prediction model fails to reliably infer personality traits from either facial features or first impressions. First impressions, however, could be inferred more reliably from facial features. We have generated artificial, extreme faces visualising the characteristics having an effect on first impressions for several traits. Conclusively, we find a relationship between first impressions, some personality traits and facial features and consolidate that people on average assess a given face in a highly similar manner. 相似文献
39.