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31.
32.
Dingjiang Liu Melanie Cocco Masazumi Matsumura Da Ren Bridget Becker Richard L. Remmele Jr. David N. Brems 《Biomolecular NMR assignments》2007,1(1):93-94
Here we report the NMR resonance assignments for the reduced form of human IgG1 CH3 domain, a 26 kDa dimer in solution (residues 341–447). The assignments have been deposited in the BioMagResBank with a BMRB
accession number of 15204. 相似文献
33.
Wenjuan Dong Heather Mead Lei Tian Jun-Gyu Park Juan I. Garcia Sierra Jaramillo Tasha Barr Daniel S. Kollath Vanessa K. Coyne Nathan E. Stone Ashley Jones Jianying Zhang Aimin Li Li-Shu Wang Martha Milanes-Yearsley Jordi B. Torrelles Luis Martinez-Sobrido Paul S. Keim Bridget Marie Barker Michael A. Caligiuri Jianhua Yu 《Journal of virology》2022,96(1)
34.
Development of Bacterium-Based Heavy Metal Biosorbents: Enhanced Uptake of Cadmium and Mercury by Escherichia coli Expressing a Metal Binding Motif 总被引:5,自引:0,他引:5 下载免费PDF全文
A gene coding for a de novo peptide sequence containing a metal binding motif was chemically synthesized and expressed in Escherichia coli as a fusion with the maltose binding protein. Bacterial cells expressing the metal binding peptide fusion demonstrated enhanced binding of Cd2+ and Hg2+ compared to bacterial cells lacking the metal binding peptide. The potential use of genetically engineered bacteria as biosorbents for the removal of heavy metals from wastewaters is discussed. 相似文献
35.
Comparative analysis of quantitative trait loci controlling glucosinolates,myrosinase and insect resistance in Arabidopsis thaliana 总被引:11,自引:0,他引:11
Evolutionary interactions among insect herbivores and plant chemical defenses have generated systems where plant compounds have opposing fitness consequences for host plants, depending on attack by various insect herbivores. This interplay complicates understanding of fitness costs and benefits of plant chemical defenses. We are studying the role of the glucosinolate-myrosinase chemical defense system in protecting Arabidopsis thaliana from specialist and generalist insect herbivory. We used two Arabidopsis recombinant inbred populations in which we had previously mapped QTL controlling variation in the glucosinolate-myrosinase system. In this study we mapped QTL controlling resistance to specialist (Plutella xylostella) and generalist (Trichoplusia ni) herbivores. We identified a number of QTL that are specific to one herbivore or the other, as well as a single QTL that controls resistance to both insects. Comparison of QTL for herbivory, glucosinolates, and myrosinase showed that T. ni herbivory is strongly deterred by higher glucosinolate levels, faster breakdown rates, and specific chemical structures. In contrast, P. xylostella herbivory is uncorrelated with variation in the glucosinolate-myrosinase system. This agrees with evolutionary theory stating that specialist insects may overcome host plant chemical defenses, whereas generalists will be sensitive to these same defenses. 相似文献
36.
B Wardley-Smith C Dore J Coleman A Cowey M J Halsey S Hudson 《Journal of applied physiology》1991,70(2):497-503
The effects of high helium pressure on the subsequent acquisition of spatial memory were studied in male rats. Thirty-two rats were exposed to 65 ATA helium-oxygen pressure for 4.2 days, decompressed (total time in chamber 5 days), and then tested in an eight-arm radial maze. Thirty-two control rats were exposed in the chamber to 1 ATA air. Each rat had 20 sessions in the maze (2 sessions/day for 10 days), and the number of correct (visiting an arm not previously visited to obtain the reward pellet) and incorrect choices (visiting a previously visited arm) were recorded. Statistical analysis showed that the rats exposed to 65 ATA performed significantly better than 1-ATA controls during the first 8 of 20 sessions. This effect was most pronounced in sessions 5-8. Results for sessions 9-20 showed that the pressure-treated rats still made more correct choices but to an extent that did not always reach statistical significance. Possible explanations include the pressure-treated rats performing better because of hunger after a lower food consumption at pressure. Alternatively, pressure itself may enhance proposed mechanisms of spatial memory such as long-term potentiation. 相似文献
37.
Crisan M Yap S Casteilla L Chen CW Corselli M Park TS Andriolo G Sun B Zheng B Zhang L Norotte C Teng PN Traas J Schugar R Deasy BM Badylak S Buhring HJ Giacobino JP Lazzari L Huard J Péault B 《Cell Stem Cell》2008,3(3):301-313
Mesenchymal stem cells (MSCs), the archetypal multipotent progenitor cells derived in cultures of developed organs, are of unknown identity and native distribution. We have prospectively identified perivascular cells, principally pericytes, in multiple human organs including skeletal muscle, pancreas, adipose tissue, and placenta, on CD146, NG2, and PDGF-Rbeta expression and absence of hematopoietic, endothelial, and myogenic cell markers. Perivascular cells purified from skeletal muscle or nonmuscle tissues were myogenic in culture and in vivo. Irrespective of their tissue origin, long-term cultured perivascular cells retained myogenicity; exhibited at the clonal level osteogenic, chondrogenic, and adipogenic potentials; expressed MSC markers; and migrated in a culture model of chemotaxis. Expression of MSC markers was also detected at the surface of native, noncultured perivascular cells. Thus, blood vessel walls harbor a reserve of progenitor cells that may be integral to the origin of the elusive MSCs and other related adult stem cells. 相似文献
38.
Kite GC Stoneham CA Veitch NC Stein BK Whitwell KE 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2006,838(1):63-70
Liquid chromatography-mass spectrometry (LC-MS) analysis of methanol extracts of Oenanthe crocata roots revealed that oenanthotoxin co-eluted with another major polyalkyne, 2,3-dihydro-oenanthotoxin, using the existing high performance liquid chromatography (HPLC) method (isocratic elution from C18 with aqueous methanol) for investigating Oenanthe poisoning. Positive ES or APCI gave [(M+H)-H(2)O](+) and its methanol adduct as major ion species for oenanthotoxin, whereas 2,3-dihydro-oenanthotoxin formed [M+H](+) and its methanol adduct. The two polyalkynes could be chromatographically resolved on C18 by gradient elution with aqueous acetonitrile. This provides superior analysis for oenanthotoxin using HPLC with photodiode array (PDA) detection alone, but for LC-MS/MS aqueous acetonitrile was less suitable due to poor ionisation and, with APCI, an increase in the relative abundance of a [M-1](+) species, which could confuse compound assignment. HPLC-PDA and LC-MS/MS methods using an aqueous acetonitrile or aqueous methanol mobile phase, respectively, were successful when applied to the analysis of the stomach contents of a pony suspected to have eaten O. crocata. Relevant product ion spectra, by ion trap MS/MS, accurate mass data and complete sets of (1)H and (13)C NMR spectral assignments are given for the two compounds. 相似文献
39.
K. M. Jenkinson Jan M. Morgan John B. Furness Bridget R. Southwell 《Histochemistry and cell biology》1999,112(3):233-246
The localisation of NK3 tachykinin receptors in guinea-pig ileum was studied using the fluorescently labelled agonists, Cy3.5-neurokinin A and Cy3.5-kassinin.
Binding to nerve cell bodies in the myenteric and submucosal plexuses was visualised using confocal microscopy. Binding to
NK1 receptors was blocked by the NK1 receptor antagonist, CP-99994. NK3 receptors, demonstrated by binding in the presence of CP-99994, occurred in 72% of myenteric and 38% of submucosal neurons.
Colocalisation with other markers was examined to deduce the classes of neurons with NK3 receptors. In myenteric ganglia, NK3 receptors were present on the following: 73% of calbindin-immunoreactive (IR) intrinsic primary afferent neurons, 63% of
calretinin-IR excitatory motor neurons and ascending interneurons, 63% of nitric oxide synthase-IR inhibitory motor neurons
and descending interneurons, 79% of strongly neuropeptide Y (NPY)-IR secretomotor neurons, 67% of weakly NPY-IR descending
interneurons and motor neurons, and 46% of NK1 receptor-IR neurons. In submucosal ganglia, NK3 receptors were on 65% of calretinin-IR secretomotor/vasodilator neurons, 81% of NPY-IR cholinergic secretomotor neurons,
2% of vasoactive intestinal peptide-IR non-cholinergic secretomotor neurons and were completely absent from substance P-IR
intrinsic primary afferent neurons. The results support physiological studies suggesting that NK3 receptors mediate tachykinin transmission between myenteric sensory neurons and to interneurons and/or motor neurons in descending
inhibitory and ascending excitatory pathways.
Accepted: 22 June 1999 相似文献
40.
Adenoviral proteins mimic nutrient/growth signals to activate the mTOR pathway for viral replication 总被引:4,自引:0,他引:4
O'Shea C Klupsch K Choi S Bagus B Soria C Shen J McCormick F Stokoe D 《The EMBO journal》2005,24(6):1211-1221
Like tumor cells, DNA viruses have had to evolve mechanisms that uncouple cellular replication from the many intra- and extracellular factors that normally control it. Here we show that adenovirus encodes two proteins that activate the mammalian target of rapamycin (mTOR) for viral replication, even under nutrient/growth factor-limiting conditions. E4-ORF1 mimics growth factor signaling by activating PI3-kinase, resulting in increased Rheb.GTP loading and mTOR activation. E4-ORF4 is redundant with glucose in stimulating mTOR, does not affect Rheb.GTP levels and is the major mechanism whereby adenovirus activates mTOR in quiescent primary cells. We demonstrate that mTOR is activated through a mechanism that is dependent on the E4-ORF4 protein phosphatase 2A-binding domain. We also show that mTOR activation is required for efficient S-phase entry, independently of E2F activation, in adenovirus-infected quiescent primary cells. These data reveal that adenovirus has evolved proteins that activate the mTOR pathway, irrespective of the cellular microenvironment, and which play a requisite role in viral replication. 相似文献