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The first reported structure-activity relationships (SARs) about the N-[3-methoxy-4-(5-oxazolyl)phenyl moiety for a series of recently disclosed inosine monophosphate dehydrogenase (IMPDH) inhibitors are described. The syntheses and in vitro inhibitory values for IMPDH II, and T-cell proliferation (for select analogues) are given.  相似文献   
76.
The development of a series of novel indole-based inhibitors of 5'-inosine monophosphate dehydrogenase (IMPDH) is described. Various hydrogen bond acceptors at C-3 of the indole were explored. The synthesis and the structure-activity relationships (SARs) derived from in vitro studies are outlined.  相似文献   
77.
Further optimization of the beta-aminoester class of factor Xa (fXa) inhibitors is described culminating in the identification of 9c (FXV673), a potent and selective factor Xa inhibitor with excellent in vivo anticoagulant activity. An X-ray structure of FXV673 bound to human fXa is also presented. Based on its selectivity, potent in vivo activity and favorable pre-clinical safety profile, FXV673 was selected for further development and is currently undergoing clinical trials.  相似文献   
78.
Phagocytosis is a phosphatidylinositol-3-OH-kinase (PI(3)K)-dependent process in macrophages. We identified Myo10 (Myosin-X), an unconventional myosin with pleckstrin homology (PH) domains, as a potential downstream target of PI(3)K. Myo10 was recruited to phagocytic cups in a wortmannin-sensitive manner. Expression of a truncation construct of Myo10 (Myo10 tail) in a macrophage cell line or cytosolic loading of anti-Myo10 antibodies in bovine alveolar macrophages inhibited phagocytosis. In contrast, expression of a Myo10 tail construct containing a point mutation in one of its PH domains failed to inhibit phagocytosis. Expression of Myo10 tail inhibited spreading, but not adhesion, on IgG-coated substrates, consistent with a function for Myo10 in pseudopod extension. We propose that Myo10 provides a molecular link between PI(3)K and pseudopod extension during phagocytosis.  相似文献   
79.
Three genera of macrophytic red algae ( Ochtodes , Plocamium , and Portieria ) contain novel halogenated monoterpenes. To develop an in vitro system for studying halogenated monoterpene production, a laboratory tissue culture was established for Ochtodes secundiramea (Montagne) Howe (Cryptonemiales, Rhizophyllidaceae). Specifically, callus cells were induced from thallus explants of O. secundiramea plants. Shoot primordia regenerated from callus cells and developed into plantlets that released tetraspores. A sporeling from one of these tetraspores was selected for further culture. Axenic plantlets were cultivated in ESS-enriched natural seawater. Thallus tissue was cut into small pieces before subculture. Each plantlet grew as a symmetrical array of highly branched shoot tissues emanating from a common center, ultimately assuming a spherical shape of 20 mm diameter 4 weeks after subculture. Specific growth rates of over 20% per day were attained in bubble-aerated flask culture at an optimal temperature of 26° C and photosynthetic saturation light intensity of 200 μmol photons·m 2·s 1. The cultured plantlets contained myrcene and seven halogenated monoterpenes, based on gas chromatography–mass spectroscopy analysis of dichloromethane extracts. Although bromomyrcene was the dominant acyclic halogenated monoterpene, the cyclic halogenated monoterpenes chondrocole C and ochtodene were also produced by the O. secundiramea plantlet cultures. Halogenated monoterpene production at light-saturated growth conditions increased with decreasing nitrogen availability below 1.0 mM medium nitrate concentration (N:P ratios of 1.6:1 to 32:1). The halogenated monoterpene yield was insensitive to medium nitrate concentrations above 1.0 mM (N:P ratios of 32:1 to 320:1), where the bromomyrcene yield was 1700 μg per gram of dry cell mass.  相似文献   
80.
Eighteen culled dairy cows were randomly allocated into 1 of 5 treatment groups. Six cows were vaccinated twice (2V), 21 days apart, 3 with whole cell (2WC) and 3 with fragmented cell membrane (2FC) containing 1 x 10(9)Trichomonas fetus organisms or protein equivalent in a commercial mineral oil adjuvant vaccine. Six more cows were vaccinated once (1V), 3 with whole cell (1WC) and 3 with fragmented cell vaccine (1FC), using the same vaccine, while 6 cows were used as the unvaccinated controls. All cows were challenged with 1 x 10(5) organisms 4 weeks after the second or the only vaccination. After challenge, cervico-vaginal mucus (CVM) samples were cultured for T . fetus weekly for 9 weeks. Whole cell vaccines were superior to fragmented cell vaccines, and both performed better than no vaccination for apparent elimination of trichomonad infections in dairy cows. In addition, 2V was superior to 1V, which, in turn, was superior to no vaccination. Furthermore, clearance time was reduced most by 2V and whole cell vaccination compared with 1V and fragmented cell vaccination. Clearance time was decreased significantly in all vaccinated cows compared with that in unvaccinated cows.  相似文献   
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