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61.
Underiner TL Ruggeri B Aimone L Albom M Angeles T Chang H Hudkins RL Hunter K Josef K Robinson C Weinberg L Yang S Zulli A 《Bioorganic & medicinal chemistry letters》2008,18(7):2368-2372
Orally bioavailable, dual inhibitors of TIE-2/VEGF-R2 were identified by elaborating the C3/N13 SAR around a fused pyrrolodihydroindazolocarbazole scaffold. Analogs bearing a C3-thiophencarbonyl group were evaluated in enzymatic and cellular biochemical assays; two orally bioavailable analogs were further profiled in functional assays and found to inhibit microvessel growth in rat aortic explant cultures and inhibit Ang-1-stimulated chemotaxis of HUVECs. 相似文献
62.
Anthony E. Kincaid Kathryn F. Hudson Matthew W. Richey Jason C. Bartz 《Journal of virology》2012,86(23):12731-12740
Prion infection and pathogenesis are dependent on the agent crossing an epithelial barrier to gain access to the recipient nervous system. Several routes of infection have been identified, but the mechanism(s) and timing of in vivo prion transport across an epithelium have not been determined. The hamster model of nasal cavity infection was used to determine the temporal and spatial parameters of prion-infected brain homogenate uptake following inhalation and to test the hypothesis that prions cross the nasal mucosa via M cells. A small drop of infected or uninfected brain homogenate was placed below each nostril, where it was immediately inhaled into the nasal cavity. Regularly spaced tissue sections through the entire extent of the nasal cavity were processed immunohistochemically to identify brain homogenate and the disease-associated isoform of the prion protein (PrPd). Infected or uninfected brain homogenate was identified adhering to M cells, passing between cells of the nasal mucosa, and within lymphatic vessels of the nasal cavity at all time points examined. PrPd was identified within a limited number of M cells 15 to 180 min following inoculation, but not in the adjacent nasal mucosa-associated lymphoid tissue (NALT). While these results support M cell transport of prions, larger amounts of infected brain homogenate were transported paracellularly across the respiratory, olfactory, and follicle-associated epithelia of the nasal cavity. These results indicate that prions can immediately cross the nasal mucosa via multiple routes and quickly enter lymphatics, where they can spread systemically via lymph draining the nasal cavity. 相似文献
63.
Sarker P Shepherd J Swindells K Douglas I MacNeil S Swanson L Rimmer S 《Biomacromolecules》2011,12(1):1-5
Polymyxin peptide conjugated to the end groups of highly branched poly(N-isopropyl acrylamide) was shown to bind to a Gram negative bacterium, Pseudomonas aeruginosa . The nonbound polymer had a lower critical solution temperature (LCST) above 60 °C. However, binding caused aggregation, which was disrupted on cooling of the bacteria and polymer mixture. The data indicate that polymer binding of bacteria occurred by interaction of the end groups with lipopolysaccharide and that the binding decreased the LCST to below 37 °C. Cooling then progressed the polymer/bacteria aggregate through a bound LCST into an open polymer coil conformation that was not adhesive to P. aeruginosa . 相似文献
64.
Summary Callus was initiated from in vitro-grown plants of Gladiolus cultivars ‘Jenny Lee’ and ‘Florida Flame.’ The age of callus used for regeneration of plants was either 9 mo. old or 8 yr
old from ‘Jenny Lee,’ and 4 mo. old from ‘Florida Flame.’ Regeneration medium consisted of Murashige and Skoog’s basal salts
medium supplemented with 2.0 mg/l (9.3 μM) kinetin. This medium was supplemented with various concentrations of either bialaphos (Meiji Seika, Tokyo, Japan) or phosphinothricin
(Hoechst-Roussell, Frankfurt, Germany). Bialaphos was more effective than phosphinothricin at stimulating plant regeneration.
Plants regenerated from 8-yr-old callus of ‘Jenny Lee’ only when the regeneration medium was supplemented with 0.10 mg/l bialaphos.
A bialaphos concentration of 0.01 mg/l stimulated regeneration from 9-mo.-old callus of cultivar ‘Jenny Lee’ and 4-mo.-old
callus of ‘Florida Flame.’ 相似文献
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Background
Thioredoxin reductase (TR) is a redox active protein involved in many cellular processes as part of the thioredoxin system. Presently there are three recognised forms of mammalian thioredoxin reductase designated as TR1, TR3 and TGR, that represent the cytosolic, mitochondrial and novel forms respectively. In this study we elucidated the genomic organisation of the mouse (Txnrd1) and human thioredoxin reductase 1 genes (TXNRD1) through library screening, restriction mapping and database mining. 相似文献69.
70.
Severe Plasmodium falciparum malaria encompasses a complex syndrome affecting many organs and causing physiological perturbations that have many features in common with children with sepsis. Among these, metabolic acidosis has emerged as a central feature of severe malaria and is the best independent predictor of a fatal outcome in both adults and children. There is now clear evidence that intravascular hypovolaemia (shock) is common in children with malarial acidosis. How it should be treated presents a therapeutic dilemma because acidosis often coexists with impaired consciousness (cerebral malaria). We summarize the results of recent clinical trials examining the safety and efficacy of volume expansion in children with 'cerebral malaria' complicated by acidosis. 相似文献