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Chunjian Liu James Lin Gerry Everlof Christoph Gesenberg Hongjian Zhang Punit H. Marathe Mary Malley Michael A. Galella Murray Mckinnon John H. Dodd Joel C. Barrish Gary L. Schieven Katerina Leftheris 《Bioorganic & medicinal chemistry letters》2013,23(10):3028-3033
A series of carbamoylmethylene linked prodrugs of 1 (BMS-582949), a clinical p38α inhibitor, were synthesized and evaluated. Though the phosphoryloxymethylene carbamates (3, 4, and 5) and α-aminoacyloxymethylene carbamates (22, 23, and 26) were found unstable at neutral pH values, fumaric acid derived acyloxymethylene carbamates (2, 28, and 31) were highly stable under both acidic and neutral conditions. Prodrugs 2 and 31 were also highly soluble at both acidic and neutral pH values. At a solution dose of 14.2 mpk (equivalent to 10 mpk of 1), 2 gave essentially the same exposure of 1 compared to dosing 10 mpk of 1 itself. At a suspension dose of 142 mpk (equivalent to 100 mpk of 1), 2 demonstrated that it could overcome the solubility issue associated with 1 and provide a much higher exposure of 1. To our knowledge, the unique type of prodrugs like 2, 28, and 31 was not reported in the past and could represent a novel prodrug approach for secondary amides, a class of molecules frequently identified as drug candidates. 相似文献
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Andrew F Galloway Jumana Akhtar Emma Burak Susan E Marcus Katie J Field Ian C Dodd Paul Knox 《Plant physiology》2022,190(2):1214
Root exudates and rhizosheaths of attached soil are important features of growing roots. To elucidate factors involved in rhizosheath formation, wild-type (WT) barley (Hordeum vulgare L. cv. Pallas) and a root hairless mutant, bald root barley (brb), were investigated with a combination of physiological, biochemical, and immunochemical assays. When grown in soil, WT barley roots bound ∼5-fold more soil than brb per unit root length. High molecular weight (HMW) polysaccharide exudates of brb roots had less soil-binding capacity than those of WT root exudates. Carbohydrate and glycan monoclonal antibody analyses of HMW polysaccharide exudates indicated differing glycan profiles. Relative to WT plants, root exudates of brb had reduced signals for arabinogalactan-protein (AGP), extensin, and heteroxylan epitopes. In contrast, the root exudate of 2-week-old brb plants contained ∼25-fold more detectable xyloglucan epitope relative to WT. Root system immunoprints confirmed the higher levels of release of the xyloglucan epitope from brb root apices and root axes relative to WT. Epitope detection with anion-exchange chromatography indicated that the increased detection of xyloglucan in brb exudates was due to enhanced abundance of a neutral polymer. Conversely, brb root exudates contained decreased amounts of an acidic polymer, with soil-binding properties, containing the xyloglucan epitope and glycoprotein and heteroxylan epitopes relative to WT. We, therefore, propose that, in addition to physically structuring soil particles, root hairs facilitate rhizosheath formation by releasing a soil-binding polysaccharide complex.The root exudate of a root hairless mutant of barley, relative to wild type, has an altered pattern of polysaccharide epitopes and lesser amounts of an acidic soil-binding polysaccharide complex. 相似文献
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OBJECTIVE: To review the cytologic findings of vitreous specimens and propose a simplified approach to them. STUDY DESIGN: Seventy-four vitreous specimens from 60 patients obtained either during a pars plana vitrectomy or by vitreous aspiration were reviewed. Clinical correlation was obtained on all patients. RESULTS: Findings suggestive of a specific disorder were present in 30 specimens (41%); cytologic examination of the remaining 44 showed nonspecific changes. A lymphoproliferative disorder, the intraocular malignancy suspected most often in this series, was identified in eight specimens (11%). Large cell lymphomas were evident in 5 specimens, 2 specimens were suspicious for lymphoma, and 1 specimen was consistent with plasmacytoma. Twelve specimens (16%) contained hemorrhage. In rare instances, specific infectious agents, such as parasites (5%), bacteria (1%) and fungi (3%), could be identified. The diagnosis of viral infections required ancillary studies. Lens fragments were identified in four cases (5%), and a diagnosis of lens-induced endophthalmitis could be rendered in one case (1%). Changes consistent with sarcoidosis were present in 3% of cases. CONCLUSION: Based on this experience with vitreous specimens submitted for clinical reasons, we found that they could be divided into three broad diagnostic categories: inflammation/infection (54 specimens/41 patients), hemorrhage (12 specimens/12 patients) and malignancy (8 specimens/7 patients). 相似文献
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