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381.
Cranial neural crest cells (CNCCs) give rise to cranial mesenchyme (CM) that differentiates into the forebrain meningeal progenitors in the basolateral and apical regions of the head. This occurs in close proximity to the other CNCC‐CM‐derivatives, such as calvarial bone and dermal progenitors. We found active Wnt signaling transduction in the forebrain meningeal progenitors in basolateral and apical populations and in the non‐meningeal CM preceding meningeal differentiation. Here, we dissect the source of Wnt ligand secretion and requirement of Wnt/β‐catenin signaling for the lineage selection and early differentiation of the forebrain meninges. We find persistent canonical Wnt/β‐catenin signal transduction in the meningeal progenitors in the absence of Wnt ligand secretion in the CM or surface ectoderm, suggesting additional sources of Wnts. Conditional mutants for Wntless and β‐catenin in the CM showed that Wnt ligand secretion and Wnt/β‐catenin signaling were dispensable for specification and proliferation of early meningeal progenitors. In the absence of β‐catenin in the CM, we found diminished laminin matrix and meningeal hypoplasia, indicating a structural and trophic role of mesenchymal β‐catenin signaling. This study shows that β‐catenin signaling is required in the CM for maintenance and organization of the differentiated meningeal layers in the basolateral and apical populations of embryonic meninges. 相似文献
382.
Sree Kanth Sivan Radhika Vangala Vijjulatha Manga 《Bioorganic & medicinal chemistry》2013,21(15):4591-4599
Induced fit molecular docking studies were performed on BMS-806 derivatives reported as small molecule inhibitors of HIV-1 gp120–CD4 binding. Comprehensive study of protein–ligand interactions guided in identification and design of novel symmetrical N,N′-disubstituted urea and thiourea as HIV-1 gp120–CD4 binding inhibitors. These molecules were synthesized in aqueous medium using microwave irradiation. Synthesized molecules were screened for their inhibitory ability by HIV-1 gp120–CD4 capture enzyme-linked immunosorbent assay (ELISA). Designed compounds were found to inhibit HIV-1 gp120–CD4 binding in micromolar (0.013–0.247 μM) concentrations. 相似文献
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385.
Shashi K. Khurana Velagalety Krishnamoorthy Virinder S. Parmar Radhika Sanduja Harmohinder L. Chawla 《Phytochemistry》1982,21(8):2145-2146
A trimethylcoumarin has been isolated, for the first time from the stem of Trigonelia foenum-graecum along with some known compounds. Based upon spectral and analytical data and comparison with a synthetic sample, it has been assigned the structure 3, 4, 7-trimethylcoumarin. 相似文献
386.
Phenol oxidase activity in the hemolymph of male Streptocephalus dichotomus is only 1/3rd of that of females. About 70% of
this activity resides in cell lysate and 30% in plasma. Electrophoretic analysis revealed that male plasma has a single fraction
of tyrosine hydroxylase, evidenced by positivity towards tyrosine methylester-PMS-NBT. Female hemolymph has as many as three
isozymes showing diphenoloxidase activity. The significance of these results is discussed with reference to sex-linked enzyme
activity and its possible role in longevity.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
387.
William C. Groutas Lee S. Chong Jeffrey B. Epp Radhika Venkataraman Michael J. Brubaker Michael A. Stanga Eun-Hong Kim Charles E. Keller 《Bioorganic & medicinal chemistry letters》1992,2(12):1571-1574
The interaction of a series of derivatives of cis-N-hydroxy-3-phenyl-2-isoxazoline-4,5-dicarboximide toward human leukocyte elastase and cathepsin G was investigated. Both enzymes were rapidly acylated and the corresponding acyl enzymes exhibited variable stability. 相似文献
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389.
William C. Groutas Lee S. Chong Radhika Venkataraman He Huang Jeffrey B. Epp Rongze Kuang 《Bioorganic & medicinal chemistry letters》1993,3(12):2745-2750
A general approach toward the design of mechanism-based inhibitors of serine proteinases involving the linking of fragment -CHX-COOR to an appropriate recognition element is described. 相似文献
390.
Radhika Sanduja Kenneth L. Euler Maktoob Alam James D. Korp Ivan Bernal 《Phytochemistry》1982,21(6):1451-1453
A highly substituted chromone constituent of Couepia paraensis was isolated and identified as 5-hydroxy-2,8-dimethyl-6,7-dimethoxychromone by spect 相似文献