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1.
Ciliated tracheal epithelia cell cultures were investigated immunocytochemically with anti-tubulin and colloidal gold. When rabbit tracheal cultures were fixed in paraformaldehyde, treated with acetone, anti-tubulin and a second antibody coupled to FITC, fluorescence was associated with cytoskeletal and axonemal microtubules. Cilia covering the apical surface of the ciliated tracheal cells fluoresced very brightly thus facilitating identification of this cell type. Electron microscopy of tracheal cultures fixed as above, treated with Triton-X 100 and incubated in anti-tubulin and protein A coupled to colloidal gold resulted in the highly specific localization of tubulin in ciliary axonemes and basal bodies. Omission of primary or secondary antibody resulted in extremely low levels of fluorescence while no colloidal gold particles could be detected in cultures at the electron microscopy level when rabbit anti-tubulin was omitted. 相似文献
2.
Prasert Akkaramongkolporn Tanasait Ngawhirunpat Praneet Opanasopit 《AAPS PharmSciTech》2009,10(2):641-648
The differently sulfonated styrene–divinylbenzene cross-linked copolymer cationic exchange resins were prepared by oil-in-water
polymerization and varied degrees of sulfonation. Several characteristics of the obtained resins were evaluated, i.e., Fourier
transform infrared spectra, the ion-exchange capacity, microscopic morphology, size, and swelling. The resin characteristics
were altered in relation to the degree of sulfonation, proving that differently sulfonated resins could be prepared. The behavior
of chlorpheniramine (CPM) loading and in vitro release in the USP simulated gastric (SGF) and intestinal fluids (SIF) of the obtained resins were also evaluated. The CPM
loaded in the resinates (drug-loaded resins) increased with the increasing degree of sulfonic group and hence the drug binding
site in the employed resins. The CPM release was lower from the resins with the higher degree of sulfonic group due to the
increase in the diffusive path depth. The CPM release was obviously lower in SGF than SIF because CPM, a weak base drug, ionized
to a greater extent in SGF and then preferred binding with rather than releasing from the resins. In conclusion, the differently
sulfonated resins could be utilized as novel carriers for drug delivery. 相似文献
3.
《Bioorganic & medicinal chemistry》2019,27(12):2616-2620
Gold catalysis is a convenient tool to oxidatively functionalize alkyne into a range of valuable compounds. In this article, we report a new access to isochroman-4-one and 2H-pyran-3(6H)-one derivatives that involves a gold-catalyzed oxidative cycloalkoxylation of an alkyne in the presence of a pyridine N-oxide. The reaction proceeds under mild conditions, is relatively efficient and exhibits a high functional group compatibility. 相似文献
4.
The chemiluminescence (CL) of bis(2,4,6‐trichlorophyenyl) oxalate with hydrogen peroxide in the present of cationic surfactant and gold nanoparticles was studied. The CL emission was obviously enhanced in the presence of surfactant at a suitable concentration, with a synergetic catalysis effect exhibited. Different sizes of gold nanoparticles (15 and 50 nm) showed different effects on CL intensity. Mechanisms of the CL reaction and sensitization effect are discussed. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
5.
P A Coulombe M Bendayan 《Biology of the cell / under the auspices of the European Cell Biology Organization》1989,65(1):83-86
The membrane content in phospholipids along the secretory pathway in rat pancreatic B-cells was studied in situ by high-resolution cytochemistry, applying the recently introduced phospholipase A2-gold technique. The gold particles were mostly associated with cell membranes, and the various types of membranes were labeled to a different extent. Quantitation of the labeling over these membranes revealed a heterogeneous distribution of the labeling across the secretory pathway. This heretogeneity occurred mainly as a progressive, decreasing gradient in the first half of this pathway, between the rough endoplasmic reticulum and the mi-cisternae of the Golgi apparatus. The labeling density remained at a lower level in the trans-most Golgi cisternae and immature secretory granule membranes, to increase in the mature secretory granule membrane, where it reached the value found in the plasma membrane. These results provide evidence that the functional heterogeneity existing across the membrane forming the secretory pathway is parallelled by substantial changes in their phospholipid content. 相似文献
6.
Bård Smedsrød Marie Malmgren Jan Ericsson Torvard C. Laurent 《Cell and tissue research》1988,253(1):39-45
Summary Endocytosis via the hyaluronic acid/chondroitin sulphate receptor of rat liver endothelial cells was studied ultrastructurally, by use of a probe consisting of chondroitin sulphate proteoglycan attached to 15-nm gold particles. The probe bound to the surface of the cells exclusively in coated regions of the plasma membrane. Internalization at 37° C took place in less than one minute during which time interval the bound probe was transferred to coated vesicles. Further transfer to lysosomes was delayed in association with an accumulation of probes in a prelysosomal compartment consisting of large vacuoles in which probes lined the inner aspect of the membrane. Transport to lysosomes occurred only after a lag phase of at least 40–60 min at 37° C.Abbreviations
CS
chondroitin sulphate
-
CSPG
chondroitin sulphate proteoglycan
-
CSPG-Au
CSPG-gold complex
-
EM
electronmicroscopical or electron microscopy
-
HA
hyaluronic acid
-
KC
Kuppfer cells
-
LEC
liver endothelial cells
-
PC
parenchymal cells
-
RES
reticuloendothelial system 相似文献
7.
Summary Electron-microscopic immunocytochemistry for the demonstration of CCK-like material in basal endocrine cells of the midgut of Aeschna cyanea, Locusta migratoria, Carausius morosus and Periplaneta americana was performed by use of the peroxidase-antiperoxidase procedure and the colloidal gold method. Immunoreactive cells appeared scattered among digestive and regenerative cells of the epithelium. Immunoreactivity was specifically detected over round to oval electron-dense granules whose size appeared rather different from species to species. Thus, the average size of 30% (d30) of the largest granules ranged from 312 nm in Periplaneta americana to 159 nm in Carausius morosus with intermediate values in Aeschna cyanea (d30=195 nm) and Locusta migratoria (d30=225 nm). 相似文献
8.
Bovine-serum-albumin coated colloidal gold particles were injected intravenously into healthy, adult domestic ducks. The fate of these tracer particles was followed in a time-sequence up to 4.5 days in the renal glomerular mesangium--distal tubule macula densa junction with transmission electron microscopy. The bulk of particle aggregates is 'trapped' in the mesangial channel system, phagocyted by mesangial cells, exocyted back into the mesangial channels, transported extracellularily towards the vascular hilus, rephagocyted by macula densa cells and expelled into the tubular lumen. This process requires about nineteen hours in the experimental model chosen, although it continues to take place to a much lower extent even 4.5 days after administration of the tracer. This mode of macromolecular excretion may be of interest in connection with the pathogenesis of several forms of glomerulonephritis. 相似文献
9.
A comparative study on tyrosine oxidation was made with a pure cationic and anionic peroxidase from peanut cell culture medium. The results showed that both isozymes possessed almost identical capacity to oxidize tyrosine to dityrosine, isodityrosine and polytyrosine with the main difference being the pH optimum (pH 4 for the anionic and pH 7 for the cationic isozyme). Variation of reaction time after 1.5 h incubation had little effect on the quantity and quality of the oxidation products. On the other hand, increase of enzyme units correspondingly increased tyrosine-oxidation. The removal of heme and carbohydrate moieties from the holoenzyme arrested the reaction thereby suggesting the role played by these moieties in stabilizing the active site of peroxidase isoenzymes. Isolated cell wall extracts catalyzed the tyrosine-oxidation equally well as the purified peroxidase. Even though polyclonal antibodies against anionic peroxidase inhibited the in vitro tyrosine reaction they did not affect the tyrosine oxidation by the cell walls, while the cationic antibodies did.Abbreviations A.PRX
anionic peanut peroxidase
- C.PRX
cationic peanut peroxidase
- PcAb
polyclonal antibodies
- ELISA
enzyme-linked-immuno-sorbent-assay
- TFMS
trifluoromethane sulfonic acid 相似文献
10.
Dissolved nutrient inputs in bulk precipitation and outputs in streamwater were measured during 3 years of contrasting hydrological conditions in a 6.3-ha, grazed heathland watershed on schists in the Montseny mountains (NE Spain), drained by an intermittent stream. On average, 39% of the precipitation became streamflow. Bulk precipitation delivered positive net alkalinity (mean 0.22 keq/ha/yr), sulphate input was moderate (9.0 kg SO4-S/ha/yr), and the mean input of inorganic N was not exceptionally high (6.6 kg/ha/yr). Ion concentrations were relatively low in streamwater; SO4
2- was the dominant anion. Most concentrations in streamwater varied seasonally, with maxima in late summer or early autumn and minima in spring. This pattern probably resulted from increased availability of ions for leaching due to decomposition of organic matter and chemical weathering during the warm period. Nitrate concentrations were relatively high in winter and dropped sharply in early spring, probably because of biological uptake. Annual element outputs in streamwater varied between years and seemed to be controlled by both the amount of annual streamflow and its seasonal distribution. Annual inputs exceeded outputs for dissolved inorganic N. The watershed accumulated H+ and Ca2+, had net losses of Na+ and Mg2+, and was close to steady state for K+, SO4
2-, Cl- and alkalinity. The chloride budgets gave no evidence of substantial dry deposition in this system. The cationic denudation rate was negative (-0.14 keq/ha/yr) because Ca2+ retention was higher than net exports of Na+ and Mg2+ from silicate weathering. Low nutrient export and little production of alkalinity suggest that this watershed has a low buffering capacity. 相似文献