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51.
A modified Coomassie Brilliant Blue staining method at nanogram sensitivity compatible with proteomic analysis 总被引:4,自引:0,他引:4
A more sensitive and convenient Coomassie Brilliant Blue (CBB) staining method for visualizing proteins was developed. Compared with the modifications include the supplement of 10% (v/v) methanol into the fixing solution, an increase of an additional sensitization step and CBB raised from 0.1 to 0.125%. The improved method can detect proteins at nanogram level. The improved method is more sensitive than Blue Silver and more convenient than the Silver protocol. Mass spectrometry results confirmed that it is suitable for subsequent proteomic research. 相似文献
52.
53.
Bitte Aspenstrm-Fagerlund Birgitta Sundstrm Jonas Tallkvist Nils-Gunnar Ilbck Anders W. Glynn 《Chemico-biological interactions》2009,181(2):272-278
Passive paracellular absorption, regulated by tight junctions (TJs), is the main route for absorption of poorly absorbed hydrophilic substances. Surface active substances, such as fatty acids, may enhance absorption of these substances by affecting the integrity of TJ and increasing the permeability. It has been suggested that aluminium (Al) absorption occurs mainly by the paracellular route. Herein, we investigated if physiologically relevant exposures of fully differentiated Caco-2 cell monolayers to oleic acid and docosahexaenoic acid (DHA), which are fatty acids common in food, increase absorption of Al and the paracellular marker mannitol. In an Al toxicity test, mannitol and Al absorption through Caco-2 cell monolayers were similarly modulated by Al concentrations between 1 and 30 mM, suggesting that absorption of the two compounds occurred via the same pathways. Exposure of Caco-2 cell monolayers to non-toxic concentrations of Al (2 mM) and 14C-mannitol in fatty acid emulsions (15 and 30 mM oleic acid, 5 and 10 mM DHA) caused a decreased transepithelial electrical resistance (TEER). Concomitantly, fractional absorption of Al and mannitol, expressed as percentage of apical Al and mannitol retrieved at the basolateral side, increased with increasing dose of fatty acids. Transmission electron microscopy was applied to assess the effect of oleic acid on the morphology of TJ. It was shown that oleic acid caused a less structured morphology of TJ in Caco-2 cell monolayers. Taken together our findings indicate that fatty acids common in food increase the paracellular intestinal absorption of Al. These findings may influence future risk assessment of human Al exposure. 相似文献
54.
55.
Jan Van den Bulcke Joris Van Acker Marc Stevens 《International biodeterioration & biodegradation》2006,57(4):229-238
A computer technique for assessing blue-stained coated wood has been implemented for evaluating the discoloration of coatings and analysing the interior wood staining of samples subjected to testing according to European Standard EN 152. The comparison of visual assessment and computer-evaluated percentages of blue staining is based on a combination of correlation measures, principal components and cluster analysis. It appears difficult to imitate human evaluation with image processing, since computer ratings represent exact percentages, while subjective evaluations do not. Additionally, more specific techniques for exploring fungal growth in coated wood have been described. As EN 152 was specifically developed for testing efficacy of wood preservatives, a modified test methodology was elaborated for testing the efficacy of wood coatings, called here as the EN 152-reverse method. Furthermore three-dimensional (3D) reconstruction is validated as a tool for in-depth analysis of blue-stain disfigurement. This 3D visualisation indicates important differences in fungal infestation and proves its suitability for blue-stain resistance testing. 相似文献
56.
ABSTRACT Capturing songbirds at their nests can be challenging and time consuming. Although traps designed for capturing songbirds at their nests have been described in the literature, few are effective for capturing species with open‐cup nests. We describe a cylindrical trap designed to capture songbirds at nests up to 2 m above ground in grasses, forbs, shrubs, and small saplings. The nest trap is constructed using a rigid hoop, two pieces of mist net, three stakes, and twist ties. We used this trap to capture female Dickcissels (Spiza americana) and female Indigo Buntings (Passerina cyanea) at their nests, with success rates of 85% (N= 196) and 60–73% (N= 16), respectively. Trapping success was comparable to that using other passerine nest trap designs. Nest abandonment after trapping attempts was rare and similar to that reported in previous studies. Our nest trap is lightweight, easy to make, versatile enough to use in a variety of grassland and shrub habitats, and easily carried and deployed in the field. 相似文献
57.
M. Bhushana Reddy S. Sailaja K. Vemasevana Raju C. Nageswara Raju P. Giridhar B. Vengala Rao B. Sudhakar Reddy 《Luminescence》2011,26(6):680-684
Rare earth ions (Eu3+ or Tb3+)‐activated Ca3 Ga2 Si3O12 (CaGaSi) phosphors were synthesized by using a sol–gel method. Photoluminescence spectra of Eu3+:CaGaSi phosphors exhibited five emission bands at 578, 592, 612, 652 and 701 nm, which were assigned to the transitions (5D0 → 7F0, 7F1, 7F2, 7F3 and 7F4), respectively, with an excitation wavelength of λexci = 392 nm. Among these, the transition 5D0 → 7F2 (612 nm) displayed bright red emission. In the case of Tb3+:CaGaSi phosphors, four emission bands were observed at 488 (5D4 → 7F6), 543 (5D4 → 7F5), 584 (5D4 → 7F4) and 614 nm (5D4 → 7F3) from the measurement of PL spectra with λexci = 376 nm. Among these, the transition 5D4 → 7F5 at 543 nm displayed bright green emission. The structure and morphology of the phosphors were studied from the measurements of X‐ray diffraction (XRD), scanning electron microscopy (SEM) and energy‐dispersive X‐ray analysis (EDAX) results. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
58.
Thomas P. Brennan Pendar Ardalan Han‐Bo‐Ram Lee Jonathan R. Bakke I‐Kang Ding Michael D. McGehee Stacey F. Bent 《Liver Transplantation》2011,1(6):1169-1175
Functioning quantum dot (QD) sensitized solar cells have been fabricated using the vacuum deposition technique atomic layer deposition (ALD). Utilizing the incubation period of CdS growth by ALD on TiO2, we are able to grow QDs of adjustable size which act as sensitizers for solid‐state QD‐sensitized solar cells (ssQDSSC). The size of QDs, studied with transmission electron microscopy (TEM), varied with the number of ALD cycles from 1‐10 nm. Photovoltaic devices with the QDs were fabricated and characterized using a ssQDSSC device architecture with 2,2',7,7'‐tetrakis‐(N,N‐di‐p methoxyphenylamine) 9,9'‐spirobifluorene (spiro‐OMeTAD) as the solid‐state hole conductor. The ALD approach described here can be applied to fabrication of quantum‐confined structures for a variety of applications, including solar electricity and solar fuels. Because ALD provides the ability to deposit many materials in very high aspect ratio substrates, this work introduces a strategy by which material and optical properties of QD sensitizers may be adjusted not only by the size of the particles but also in the future by the composition. 相似文献
59.
We herein report the joint occurrence of an autistic disorder (AD) and X-linked hypophosphatemia. X-linked hypophosphatemia (XLH), an X-linked dominant disorder, is the most common of the inherited renal phosphate wasting disorders. Autism is a pervasive developmental disorder that occurs mainly due to genetic causes. In approximately 6-15% of cases, the autistic phenotype is a part of a broader genetic condition called syndromic autism.Therefore, reports of cases with the joint occurrence of a known genetic syndrome and a diagnosis of ASD by a child psychiatrist are relevant. A joint occurrence does not, however, mean that there is always a causal link between the genetic syndrome and the autistic behavioural phenotype. In this case, there are a number of arguments countering a causal link. 相似文献
60.
Tammi L. Richardson urea M. Ciotti John J. Cullen Tracy A. Villareal 《Journal of phycology》1996,32(5):741-757
Cultures of Rhizosolenia formosa H. Peragallo were studied to assess whether or not physiological and optical characteristics of this large diatom were consistent with the ability to migrate vertically in the open ocean. Time-course experiments examined changes in chemical composition and buoyancy of R. formosa during nitrate (N)–replete growth, N starvation, and recovery. Cells could maintain unbalanced growth for at least 53 h after depletion of ambient nitrate. Increases in C:N and carbohydrate: protein ratios observed during N starvation reversed within 24 h of reintroduction of nitrate to culture medium. Buoyancy was related to nutrition: Upon N depletion, the percentage of positively buoyant cells decreased to 4% from 11% but reverted to 9% within 12 h of nitrate readdition. Cells took up nitrate in the dark. Nitrogen-specific uptake rates averaged 0.48 d?1; these rates were higher than N-specific growth rates (0. 15 d?1), indicating the potential for luxury consumption of nitrate, which can be stored for later use. Measurements of photosynthesis vs. irradiance, chlorophyll-specific absorption (aph*(λ)), and pigment composition showed that cells may be adapted for growth under a wide range of irradiances. Values of aph*(λ) were lower for N-depleted cells than for N-replete cells, and N-depleted cells had higher ratios of total carotenoids to chlorophyll a. Aggregation of chloroplasts was more pronounced in N-depleted cells. These are possibly photoprotective mechanisms that would be an advantage to N-depleted cells in surface waters. Compounds that absorb in the ultraviolet region were detected in N-replete cells but were absent in N-depleted cultures. Overall, these results have important implications for migrations of Rhizosolenia in nature. Cells may survive fairly long periods in N-depleted surface waters and will continue to take up carbon; then they can resume nitrate uptake and revert to positive buoyancy upon returning to deep, N-rich water. Uncoupled uptake of carbon and nitrogen during migrations of Rhizosolenia is a form of new production that may result in the net removal of carbon from oceanic surface waters. 相似文献