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31.
Antigenic relationships between human and cobra complement factors C3 and cobra venom factor (CVF) from the Indian cobra (Naja naja) 总被引:2,自引:0,他引:2
G Eggertsen A Lundwall U Hellman J Sj?quist 《Journal of immunology (Baltimore, Md. : 1950)》1983,131(4):1920-1923
The presence of a factor immunologically related to cobra venom factor (CVF) was demonstrated in serum and plasma from the Indian cobra (Naja naja kaoutia). The factor was purified from cobra plasma by affinity chromatography on an anti-CVF gel and was found to consist of a protein composed of two polypeptide chains similar in size to those of human C3. With use of immunoblotting technique, common antigenic determinants were found in the smaller chain of the prepared material and the beta-chain of human C3; the larger chain may display antigenic determinants present in the alpha-chain of human C3. These findings suggest that this molecule represents the C3 of the cobra complement system. Common antigenic determinants were also demonstrated in the alpha-chain of CVF and the beta-chains of human and cobra C3. No reactions were observed between the beta- and gamma-chains of CVF and any antiserum against human C3 or its subunits. Upon immunodiffusion analysis, cobra serum was found to contain a factor besides C3 sharing antigens specific for CVF, while cobra C3 was antigenically deficient compared to CVF. This suggests that cobra C3 physiologically is degraded to a molecule very similar to or identical with CVF. 相似文献
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R. Håkanson F. Sundler A. Nobin N. -O. Sjöberg L. Edvinsson L. -I. Larsson 《Cell and tissue research》1974,150(2):281-290
Summary In the mammalian pituitary formaldehyde-ozone treatment induces strong fluorescence in the cells of the pars intermedia and moderate to strong fluorescence in numerous cells of the pars distalis. Maximum excitation is at 370–375 nm and maximum emission at 495–505 nm. The properties of the cellular fluorescence are indistinguishable from those of tryptamine or peptides with NH2-terminal tryptophan. From chemical analysis such peptides seem to occur abundantly in the mammalian pituitary. The concentration of these peptides agrees very well with the number and fluorescence intensity of the cells in all species studied. Furthermore, the tryptophyl peptides in the various parts of the pig pituitary have a distribution quite parallel to that of the fluorescent cells. As we have failed to detect tryptamine in the pituitary, we conclude that the formaldehyde-ozone-induced fluorescence in the adenohypophysis reflects the presence of tryptophyl peptides.This study was supported by grants from the Swedish Medical Research Council (04X-1007; 04X-3764), the Ford Foundation, Harald and Greta Jeanssons stiftelse and Riksföreningen mot Cancer (660-K73-01X).For brevity occasionally referred to as tryptophyl peptides. 相似文献
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R. Håkanson L. -I. Larsson N. -O. Sjöberg F. Sundler 《Histochemistry and cell biology》1974,38(3):259-270
Summary The urethra and prostate of the guinea-pig contain at least two types of endocrine-like cells in the epithelium. The predominant type is argentaffin and stores 5-hydroxytryptamine. Treatment with reserpine or a dopa decarboxylase inhibitor markedly reduces the 5-hydroxytryptamine content of this cell type. The other less numerous cell type, which is argyrophil but not argentaffin, is devoid of 5-hydroxytryptamine but can be induced to store dopamine if supplied with dopa. Both cell types occur disseminated in the urethral epithelium, whilst only the argyrophyl, non-argentaffin cell type devoid of 5-hydroxytryptamine is found in the prostate. At the ultrastructural level the argentaffin cell type contains numerous electron-dense cytoplasmic 800–1000 Å granules. These granules are argentaffin, suggesting that they are the storage site for 5-hydroxytryptamine. The cells sometimes reach the urethral lumen via a narrow neck, the apex being endowed with microvilli. This arrangement suggests that the cells are capable of responding to stimuli in the urethral lumen. Preliminary attempts to test the effect of depriving or loading guinea-pigs with water failed to induced changes in the 5-hydroxytryptamine content of the urethral endocrine-like cells. 相似文献
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The copolymeric structure of pig skin dermatan sulphate. Isolation and characterization of l-idurono-sulphate-containing oligosaccharides from copolymeric chains 总被引:3,自引:3,他引:0 下载免费PDF全文
Lars-?ke Fransson Lars C?ster Birgitta Havsmark Anders Malmstr?m Ingrid Sj?berg 《The Biochemical journal》1974,143(2):379-389
Dermatan sulphate was degraded by testicular hyaluronidase and an oversulphated fraction was isolated by ion-exchange chromatography. This preparation, which contained fairly long segments derived from the non-reducing terminal portion of the molecule, was subjected to periodate oxidation under acidic conditions. The oxidized iduronic acid residues were cleaved by reduction-hydrolysis (Smith-degradation) (Fransson & Carlstedt, 1974) or by alkaline elimination. The oligosaccharides so obtained contained both GlcUA (glucuronic acid) and IdUA-SO(4) (sulphated iduronic acid) residues. Copolymeric oligosaccharides obtained after alkaline elimination were cleaved by chondroitinase-AC into disaccharide and higher oligosaccharides. Since the corresponding oligosaccharides obtained by Smith-degradation were unaffected by this enzyme, it was concluded that the carbohydrate sequences were GalNAc-(IdUA-GalNAc)(n)-GlcUA-GalNAc. The iduronic acid-containing sequences were resistant to digestion with chondroitinase-ABC. It was demonstrated that the presence of unsulphated N-acetylgalactosamine residues in these sequences could be responsible for the observed effect. This information was obtained in an indirect way. Chemically desulphated dermatan sulphate was found to be a poor substrate for the chondroitinase-ABC enzyme. Moreover, digestion with chondroitinase-ABC of chondroitinase-AC-degraded dermatan sulphate released periodate-resistant iduronic acid-containing oligosaccharides. It is concluded that copolymeric sequences of the following structure are present in pig skin dermatan sulphate: [Formula: see text] N-acetylgalactosamine moieties surrounding IdUA-SO(4) residues are unsulphated to a large extent. 相似文献
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