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481.
Chuan-Fang Wu Jian Li Jie An Li-Qing Chang Fang Chen Jin-Ku Bao 《植物学报(英文版)》2006,48(2):223-231
A novel mannose-bindlng aggiutinln was purified from bulbs of Zephyranthes candida Herb by extraction, precipitation with 80% (NH4)2SO4, and ion-exchange chromatography on DEAE-Sepharose followed by gel flitration on Sephscryl S-100. The purified Z. candida agglutlnln (ZCA) migrated as a single band of 12 kDa on sodium dodecyi suifate-poiyecryiamide gel electrophoresis under reducing and non-reducing conditions. The apparent molecular mass of the iectln, as datermlned by gel filtration chromatography, was 48 kDa. The results Indicated that ZCA was composed of four Identical subunlts of 12 kDa each (homotetramerlc nature). The ZCA agglutlhated rabbit erythrocytes, Escherichla coil and Saccharomyces cerevislae ceils at concentrations of 0.95, 1.90, and 31.30 μg/mL, respectively. Bloassays Indicated that ZCA has a significant effect on wheat aphid survival. Mortality after 7 d was 〉 90% at 0.26%. A degenerate primer was designed In accordance with the N-terminal partial sequence of purified ZCA. The full-length cDNA was cloned by 3'- and 5'-rapid amplification of cDNA ends. The full-length cDNA had 661 bp and the sequence encoded an open reading frame of 168 amino acids. The mature protein of ZCA Includes 109 amino acid residues and the molecular weight of the protein was 12.1 kDa. The result show that the zca gene encodes a protein precursor with a signal peptlde, a mature protein, and a C-terminal cleavage amino acids sequence. Molecular modeling of ZCA Indicated that Its three-dimensional atructure strongly resembies that of the snowdrop aggiutinin. Blocks' analysis revealed that the deduced amino acid sequence of ZCA has three functional domains specific for agglutination and three carbohydrate binding boxes (QDNY). 相似文献
482.
483.
Gevaert K Pinxteren J Demol H Hugelier K Staes A Van Damme J Martens L Vandekerckhove J 《Journal of proteome research》2006,5(6):1415-1428
Serial application of strong cation-exchange and diagonal reversed-phase chromatography selecting methionyl peptides by stepwise shifting them from their reduced to their sulfoxide and sulfone forms generates a four-stage fractionation system, allowing high coverage analysis of complex proteome digests by LC-MALDI-MS/MS. Application to the proteome of a human multipotent adult progenitor cell line (MAPC) identified 2151 proteins with high confidence as on average four MS/MS-spectra were linked to each protein. Our dataset contains several novel, potential marker proteins that may be evaluated as affinity-anchors for isolating different adult stem cells in further studies. Furthermore, at least 2 tyrosine kinases that were previously linked to the self-renewal potential of stem cells were identified, validating the stemness of the analyzed cells. We also present data hinting at possible involvement of the ubiquitin/proteasome machinery in steering proliferation and/or differentiation of MAPC. Finally, following comparison of the MAPC proteome with proteomes of four human differentiated cell lines reveals differential usage of chromosomal information: compared to differentiated cells, MAPC do not appear to hold any preference for expressing genes located on specific chromosomes. 相似文献
484.
Nguyen CA Konan-Kouakou YN Allémann E Doelker E Quintanar-Guerrero D Fessi H Gurny R 《AAPS PharmSciTech》2006,7(3):E54-E60
The aim of the present study was to prepare surfactant-free pseudolatexes of various methacrylic acid copolymers. These aqueous
colloidal dispersions of polymeric materials for oral administration are intended for film coating of solid dosage forms or
for direct manufacturing of manoparticles. Nanoparticulate dispersions were produced by an emulsification-diffusion method
involving the use of partially water-miscible solvents and the mutual saturation of the aqueous and organic phases prior to
the emulsification in order to reduce the initial thermodynamic instability of the emulsion. Because of the self-emulsifying
properties of the methacrylic acid copolymers, it was possible to prepare aqueous dispersions of colloidal size containing
up to 30% wt/vol of Eudragit RL, RS, and E using 2-butanone or methyl acetate as partially water-miscible solvents, but without
any surfactant. However, in the case of the cationic Eudragit E, protonation of the tertiary amine groups by acidification
of the aqueous phase was necessary to improve the emulsion stability in the absence of surfactant and subsequently to prevent
droplet coalescence during evaporation. In addition, a pseudolatex of Eudragit E was used to validate the coating properties
of the formulation for solid dosage forms. Film-coated tablets of quinidine sulfate showed a transparent glossy continuous
film that was firmly attached to the tablet. The dissolution profile of quinidine sulfate from the tablets coated with the
Eudragit E pseudolatex was comparable to that of tablets coated with an acetonic solution of Eudragit E. Furthermore, both
types of coating ensured similar taste masking. The emulsification-evaporation method used was shown to be appropriate for
the preparation of surfactant-free colloidal dispersions of the 3 types of preformed methacrylic acid copolymers; the dispersions
can subsequently be used for film coating of solid dosage forms.
Published: July 28, 2006 相似文献
485.
Secreted proteome profiling in human RPE cell cultures derived from donors with age related macular degeneration and age matched healthy donors 总被引:1,自引:0,他引:1
An E Lu X Flippin J Devaney JM Halligan B Hoffman EP Hoffman E Strunnikova N Csaky K Hathout Y 《Journal of proteome research》2006,5(10):2599-2610
Age-related macular degeneration (AMD) is characterized by progressive loss of central vision, which is attributed to abnormal accumulation of macular deposits called "drusen" at the interface between the basal surface of the retinal pigment epithelium (RPE) and Bruch's membrane. In the most severe cases, drusen deposits are accompanied by the growth of new blood vessels that breach the RPE layer and invade photoreceptors. In this study, we hypothesized that RPE secreted proteins are responsible for drusen formation and choroidal neovascularization. We used stable isotope labeling by amino acids in cell culture (SILAC) in combination with LC-MS/MS analysis and ZoomQuant quantification to assess differential protein secretion by RPE cell cultures prepared from human autopsy eyes of AMD donors (diagnosed by histological examinations of the macula and genotyped for the Y402H-complement factor H variant) and age-matched healthy control donors. In general, RPE cells were found to secrete a variety of extracellular matrix proteins, complement factors, and protease inhibitors that have been reported to be major constituents of drusen (hallmark deposits in AMD). Interestingly, RPE cells from AMD donors secreted 2 to 3-fold more galectin 3 binding protein, fibronectin, clusterin, matrix metalloproteinase-2 and pigment epithelium derived factor than RPE cells from age-matched healthy donors. Conversely, secreted protein acidic and rich in cysteine (SPARC) was found to be down regulated by 2-fold in AMD RPE cells versus healthy RPE cells. Ingenuity pathway analysis grouped these differentially secreted proteins into two groups; those involved in tissue development and angiogenesis and those involved in complement regulation and protein aggregation such as clusterin. Overall, these data strongly suggest that RPE cells are involved in the biogenesis of drusen and the pathology of AMD. 相似文献
486.
An HJ Miyamoto S Lancaster KS Kirmiz C Li B Lam KS Leiserowitz GS Lebrilla CB 《Journal of proteome research》2006,5(7):1626-1635
A glycomic approach is developed to identify oligosaccharide markers for ovarian cancer by rapidly profiling globally released oligosaccharides. Glycoproteins shed by cancer cells are found in the supernatant (or conditioned media) of cultured cells. In this approach, shed glycoproteins are profiled for their oligosaccharide content using beta-elimination conditions. Changes in glycosylation are monitored by matrix-assisted laser desorption/ionization Fourier transform ion cyclotron resonance mass spectrometry (MALDI-FTICR-MS). Because shed glycoproteins would also be found in serum, similar glycan profiling was performed to observe potential oligosaccharide markers. Oligosaccharide profiling data on a limited set of patient and normal serum samples were studied to determine potential glycan markers in ovarian cancer. We were able to demonstrate the presence of at least 15 unique serum glycan markers in all patients but absent in normal individuals. To determine the structure of the glycan biomarkers, a number of the ions were isolated and further analyzed using infrared multiphoton dissociation (IRMPD). One major advantage of this approach is that glycans are examined directly from patient sera without the need to obtain cancer biopsy specimens or to purify glycosylated proteins from these specimens. 相似文献
487.
Anél Pretorius Modupe O. Ogunrombi Hendrik Fourie Gisella Terre’Blanche Neal Castagnoli Jacobus J. Bergh Jacobus P. Petzer 《Bioorganic & medicinal chemistry》2010,18(11):4111-4118
The parkinsonian inducing agent 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and its corresponding five-membered ring analogue 1-methyl-3-phenyl-3-pyrroline are cyclic tertiary allylamines and good substrates of monoamine oxidase B (MAO-B). The MAO-B catalyzed 2-electron α-carbon oxidation of this class of substrates appears to be dependent on the presence of the allylic π-bond since the corresponding saturated piperidinyl analogue of MPTP is reported not to be an MAO-B substrate. The only saturated cyclic tertiary amine known to act as an MAO-B substrate is the 3,4-cyclopropyl analogue of MPTP, 3-methyl-6-phenyl-3-azabicyclo[4.1.0]heptane. As part of our ongoing studies we have examined the MAO-B substrate properties of the corresponding pyrrolidinyl analogue, 1-methyl-3-phenylpyrrolidine, and the 3,4-cyclopropyl analogue, 3-methyl-1-phenyl-3-azabicyclo[3.1.0]hexane. The results document that both the pyrrolidinyl analogue [Km = 234 μM; Vmax = 8.37 nmol/(min-mg mitochondrial protein)] and the 3,4-cyclopropyl analogue [Km = 148 μM; Vmax = 16.9 nmol/(min-mg mitochondrial protein)] are substrates of baboon liver mitochondrial MAO-B. We also have compared the neurotoxic potential of these compounds in the C57BL/6 mouse. The results led us to conclude that these compounds are not MPTP-type neurotoxins. 相似文献
488.
Marc Lamblin Basel Dabbas Russell Spingarn Rodrigo Mendoza-Sanchez Tian-Tian Wang Beum-Soo An Dao Chao Huang Richard Kremer John H. White James L. Gleason 《Bioorganic & medicinal chemistry》2010,18(11):4119-4137
Incorporation of zinc-binding groups into the side-chain of 1α,25-dihydroxyvitamin D3 (1,25D) fully bifunctional hybrid molecules which act both as vitamin D receptor agonists and histone deacetylase inhibitors. These bifunctional hybrids display in vitro antiproliferative activity against the AT84 squamous carcinoma cell line while lacking the in vivo hypercalcemic effects of 1,25D. 相似文献
489.
It has been confirmed that the crabs play significant roles in the structure and function of coastal wetland ecosystems, such as mangroves and salt marshes. However it is not easy to estimate the abundance and density of burrowing crabs effectively, thus a further understanding of roles of crabs in these ecosystems has been lagged. Some studies have discussed the suitability of several census techniques, such as burrow counting method in estimating crab density in mangroves. The validities of burrow counting method and other census techniques in estimating crab density, however, has not been tested in salt marshes, especially where vegetation are dense. In this study, we tested the validity of burrow counting method in estimating the densities of Chiromantes dehaani and Ilyoplax deschampsi in tidal flat with dense vegetation of Phragmites australis and Zizania aquatica at Yangtze Estuary through comparing densities estimated by the burrow counting method and the excavation. Burrow counting averagely underestimated the density of C. dehaani by 15% and the degree of underestimation varied among vegetations and habitats (from an overestimate by 23% to underestimate by 41%). Burrow counting averagely overestimated the density of I. deschampsi by 43% and the degree of overestimate varied from 0% to 133% depending on the vegetations and habitats. The percentage of occupied burrows and the number of crabs sharing one burrow were important factors influencing the validity of estimating crab density through burrow counting method. 相似文献
490.