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11.
Bård Smedsrød Håkan Pertoft Gösta Eggertsen Christer Sundström 《Cell and tissue research》1985,241(3):639-649
Summary This paper presents a study on the structure and function of Kupffer cells (KC) and liver endothelial cells (LEC) isolated by a simple and rapid technique involving 1) perfusion of the liver with collagenase; 2) cell separation by means of density centrifugation in Percoll; and 3) cell culture, taking advantage of the fact that KC and LEC differ in their preferences for growth substrate. The KC, which attach and spread under serum-free conditions on surfaces of glass or plastic during the first 15 min in culture exhibit a typical macrophage-like morphology including membrane ruffling and a heterogenous content of vacuoles. Moreover, these cells express (a) Fc receptors (FcR) for binding and phagocytosis of erythrocytes covered with immune globulin G (E-IgG), and (b) complement receptors (CR) for binding and serum dependent phagocytosis of erythrocytes covered with either human C3b or mouse inactivated C3b (iC3b). The cells also bind fluid phase fluoresceinated C3b. Approximately 30% of the KC express immune response-associated (Ia)-antigens.The LEC attach and spread on fibronectin coated surfaces, but not on glass or plastic surfaces, during the first two hours in culture with or without serum, and are morphologically distinct from KC. Cultured LEC are well spread out with no membrane ruffling and with numerous large vesicles surrounding the regularly shaped nucleus. These cells bind, but do not ingest E-IgG via the FcR, but no binding of fluid phase C3b or particle fixed C3b or iC3b can be observed. Incubation of LEC with fluorescein amine conjugates of ovalbumin or formaldehyde treated serum albumin, but not with fluoresceinated native serum albumin, results in accumulation of fluorescence specifically localized in the large perinuclear vesicles. Neither KC nor any other cell types tested have the ability to accumulate fluorescence upon incubation with these compounds. Iaantigens are not present on the LEC.Cytochemical demonstration of unspecific esterase, acid phosphatase, and peroxidase reveals different patterns and intensities of staining in KC as compared to LEC.Abbreviations Used
KC
Kupffer cells
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LEC
Liver endothelial cells
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C
Complement
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C3b
Major fragment of C3 activation
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iC3b
C3b that has been cleaved by factor I (C3b inactivator), present in serum
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meC3b
C3b produced by treating purified human C3 with methyl amine
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trC3b
C3b produced by treating purified human C3 with trypsin
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CR
Complement receptors for C3b and iC3b
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IgG
Immune globulin G
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IgM
Immune globulin M
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E
Erythrocytes
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E-IgG
E covered with anti-E IgG
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E-IgM E
covered with anti-E IgM
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E-C3b(h)
E-IgM reacted with purified human C1, C4, oxidized C2 and C3 (E-IgMC14xyC2C3b)
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E-iC3b(m)
E-IgM incubated with C5 deficient serum from AKR mice
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FcR
Receptors for the Fc portion of IgG
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FITC
Fluorescein isothiocyanate
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FITC-meC3b
FITC conjugated to meC3b
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FITC-trC3b
FITC conjugated to trC3b
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FA
Fluorescein amine
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FA-OA
Ovalbumin conjugated with FA
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FA-SA
Serum albumin conjugated with FA
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FA-FSA
Formaldehyde-treated serum albumin conjugated with FA
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Ia
Immune response-associated AcE Acid unspecific esterase acting on alpha naphtyl acetate
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NASDAE
Unspecific esterase acting on naphthol AS-D acetate
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NASDCAE
Unspecific esterase acting on napthol AS-D chloroacetate 相似文献
12.
Samples from sixty-two geolittoral sites along two rivers in northern Sweden were analysed in order to quantify possible differences in the vascular plant flora related to differences in the type of natural disturbance of the habitat (more disturbed: rapids (water flow) and lakes (wave action); less disturbed: slow-flowing stretches). We found that the mean species richness was lower along the slow-flowing stretches, than along the rapids and lakes, which were quite similar. When the geolittoral was subdivided into the three vertical belts, the floras of both the upper and middle belts exhibited this same pattern, whereas the species richness of the lower geolittoral belt was also low along the stretches of rapids. Along both rivers, the steepest gradient in mean species richness was recorded on the shores bordering rapids. The highest numbers of 'constant' species (frequency (F) > 60%); and of those which showed a statistically significant (probability (p) > 0.05) preference for a certain type of stretch in at least one of the three geolittoral belts, or in the entire geolittoral, were found along the rapids, in comparison to the flora of the slow-flowing stretches. The flora of the lake shores also comprised a large number of specific species compared to that along the slow-flowing stretches. The predominant species along the above-mentioned stretches reflect both phytogeographical and habitat differences. 相似文献
13.
Animal community structure as a function of stream size 总被引:1,自引:1,他引:0
Christer Brönmark Jan Herrmann Björn Malmqvist Christian Otto Per Sjöström 《Hydrobiologia》1984,112(1):73-79
The species-area relationship of the island biogeography theory was calculated for macroinvertebrates in 22 coastal, adjacent streams. A z-value of 0.19 was obtained. The low z-value was probably a consequence of the short distances between streams as well as high dispersal rates. In addition, a cluster analysis based on the dissimilarity of species assemblages showed that stream size was of prime importance in categorizing the streams. To a smaller extent water quality affected the community structure in the streams. 相似文献
14.
A 23 kDa protein has recently been demonstrated to participate in photosynthetic oxygen evolution by reconstitution experiments on inside-out thylakoid vesicles (Åkerlund H-E, Jansson C and Andersson B (1982) Biochim Biophys Acta 681:1–10). Here we describe the isolation of the 23 kDa protein from a spinach chloroplast extract using ion-exchange chromatography. The protein was obtained in a yield of 25% and with less than 1% of contaminating proteins. The ability of the protein to stimulate oxygen evolution in inside-out thylakoids was preserved throughout the various fractionation steps. The isolated protein was highly water soluble and appeared as a monomer. Its isoelectric point was at pH=7.3. The amino acid composition showed a high content of polar amino acids, resulting in a polarity index of 49%. The isolated protein lacked metals and other prosthetic groups. Its function as a catalytic or regulating subunit in the oxygen evolving complex is discussed. 相似文献
15.
16.
δ-Aminolevulinic acid supplied to dark grown isolated leaves or wheat causes an accumulation of protochlorophyllide which is only partly transformed to chlorophyllide α in continuous light At the same time a considerable photodestruction of both pigments takes place. By a suitable combinations of short lights flashes and dark periods it is possible, however, to obtain at least double the amount of the protochlorophyllide transformed without photodestruction. The transformation isshown to be dependent on the dark interval between the light flashes. Possible connections with the formation of the protein part of the protochlorophyllide holochrome are discussed. 相似文献
17.
Joakim Galli Urban Lendahl Gabrielle Paulsson Christer Ericsson Tomas Bergman Mats Carlquist Lars Wieslander 《Journal of molecular evolution》1990,31(1):40-50
Summary We describe the structure of a gene expressed in the salivary gland cells of the dipteranChironomus tentans and show that it encodes 1 of the approximately 15 secretory proteins exported by the gland cells. This sp115,140 gene consists of approximately 65 copies of a 42-bp sequence in a central uninterrupted core block, surrounded by short nonrepetitive regions. The repeats within the gene are highly similar to each other, but divergent repeats are present in a pattern which suggests that the repeat structure has been remodeled during evolution. The 42-bp repeat in the gene is a simple variant of the more complex repeat unit present in the Balbiani ring genes, encoding four of the other secretory proteins. The structure of the sp115,140 gene suggests that related repeat structures have evolved from a common origin and resulted in the set of genes whose secretory proteins interact in the assembly of the secreted protein fibers. 相似文献
18.
Three species,Torodrilus gelidus sp. nov. (subfamily Rhyacodrilinae),Rossidrilus terraenovae gen. et sp. nov. (Limnodriloidinae), and a second unnamed species of Limnodriloidinae, are reported from marine sediments in Terra Nova Bay, Ross Sea. Torodrilus gelidus is distinguished fromT. lowryi Cook, 1970 by its setal pattern (with few exceptions, both anterior and posterior setae are single-pointed in sexually mature specimens ofT. gelidus) and the morphology of its male protuberances (the latter folded over a midventral bursa in segment XI).Rossidrilus terraenovae is characterized by large diverticula attached to the oesophagus in the posterior part of segment IX, unpaired male and spermathecal pores, heavily muscular and entally ciliated atrial ampullae, elongate prostatic pads, and a deep, unpaired and muscular, copulatory sac. It is the first species of its subfamily to be described from Antarctic waters. 相似文献
19.
Béla Böddi Birgitta McEwen Margareta Ryberg Christer Sundqvist 《Physiologia plantarum》1994,92(1):160-170
Low-temperature fluorescence emission spectra of 6.5-day-old dark-grown epicotyls of pea ( Pisum sativum ) revealed the presence of protochlorophyll(ide). The upper part of the epicotyl contained 30% of the protochlorophyll(ide) content per fresh weight found in pea leaves, whereas the lower part contained 3%. Three discrete spectral forms of protochlorophyll(ide) were clearly distinguished after Gaussian deconvolution of fluorescence excitation and emission spectra. Adding the satellite bands of the Qy(0-0) transitions (the emission vibrational (Emv) bands with correlated amplitudes, gave the following delineation: Ex439–Em629–Emv684, Ex447–Em636–Emv700 and Ex456–Em650–Emv728. Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) followed by immunodetection of whole tissue extracts of the epicotyl indicated the presence of NADPH-protochlorophyllide oxidoreductase (EC 1.3.1.33). Electron micrographs showed prolamellar bodies in at most 11 % of the plastid profiles of the epicotyl cells. These prolamellar bodies were smaller, and many of them showed less regular structure than those of the leaves. Taken together, the results indicate that the protochlorophyll(ide) in epicotyls is arranged in a different way than in leaves. 相似文献
20.