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1.
Quantitative determination of the sulfated glycoproteins present in tissue and secretion fluid was performed. After digestion of the specimen with pronase in order to convert glycoproteins to glycopeptides, the sulfated glycopeptides were separated from a mixture of acidic glycans (glycosaminoglycans, sialoglycopeptides and sulfated glycopeptides) by two-dimensional electrophoresis on cellulose acetate membrane [(1986) J. Biochem. Biophys. Methods 12, 239-246]. After staining with alcian blue, the spot of sulfated glycopeptide on the cellulose acetate membrane was cut out, and then only the dye bound to the sulfated glycopeptide was extracted with a 5% cetylpyridinium chloride solution at 100 degrees C for 15 min. The extract was then measured by absorbance at 615 nm using an authentic sulfated glycopeptide as a standard. This method facilitated the determination of sulfated glycopeptides, which were separated from other acidic glycans, within the range 0-25 micrograms.  相似文献   

2.
Effect of various duration of hypokinesia on structural-metabolic characteristics of the lumbar vertebral segment has been studied in Wistar rats. Hypokinesia results in certain morphological changes of the spongy bone and tissues of the intervertebral disk, demonstrating as delayed processes of ossification, disturbed course of organization into bundles of collagenous fibers of the fibrous ring, widening of the nucleus pulposus zone. Polarization-optical investigations reveal some disturbances in the macro-molecular organization of collagen, expressed as decreasing degree of its refraction and as redistribution of glycosaminoglycans towards increasing sulfated keratan sulfates.  相似文献   

3.

Main conclusion

This work investigated a correlation between the three-dimensional architecture and compound–components of the brown algal cell wall. Calcium greatly contributes to the cell wall integrity.Brown algae have a unique cell wall consisting of alginate, cellulose, and sulfated polysaccharides. However, the relationship between the architecture and the composition of the cell wall is poorly understood. Here, we investigated the architecture of the cell wall and the effect of extracellular calcium in the sporophyte and gametophyte of the model brown alga, Ectocarpus siliculosus (Dillwyn) Lyngbye, using transmission electron microscopy, histochemical, and immunohistochemical studies. The lateral cell wall of vegetative cells of the sporophyte thalli had multilayered architecture containing electron-dense and negatively stained fibrils. Electron tomographic analysis showed that the amount of the electron-dense fibrils and the junctions was different between inner and outer layers, and between the perpendicular and tangential directions of the cell wall. By immersing the gametophyte thalli in the low-calcium (one-eighth of the normal concentration) artificial seawater medium, the fibrous layers of the lateral cell wall of vegetative cells became swollen. Destruction of cell wall integrity was also induced by the addition of sorbitol. The results demonstrated that electron-dense fibrils were composed of alginate-calcium fibrous gels, and electron negatively stained fibrils were crystalline cellulose microfibrils. It was concluded that the spatial arrangement of electron-dense fibrils was different between the layers and between the directions of the cell wall, and calcium was necessary for maintaining the fibrous layers in the cell wall. This study provides insights into the design principle of the brown algal cell wall.
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4.
Incorporation of titanium mesh in orbital and midface reconstruction   总被引:3,自引:0,他引:3  
Several authors have demonstrated the safety and effectiveness of titanium in orbital reconstruction. One question posed by clinicians is what happens to large pieces of titanium in communication with the paranasal sinuses or nasal-oral-pharyngeal area. This question becomes increasingly relevant as titanium is used to reconstruct extensive defects for which the destruction of bony architecture requires the placement of mesh in proximity to these areas. The objective of this study was to examine the gross and histologic soft-tissue response to large segments of titanium mesh in the setting of orbital and midface reconstruction, particularly when exposed to the nasal-oral-pharyngeal area and paranasal sinuses. In this study, large segments of titanium mesh were used in eight patients to reconstruct orbital and midface defects, with direct communication between the mesh and nasal-oral-pharyngeal area and paranasal sinuses. Four patients had suffered self-inflicted gunshot wounds; as a result, much of their midface was missing, including the inferior and medial orbital floor, maxilla, nose, naso-orbital-ethmoid complex, and hard palate. Extensive sheets of titanium mesh were used to reconstruct their medial and inferior orbital walls, nasal bridge, and maxilla. In the fifth patient, titanium mesh was used to reconstruct the maxilla after resection of a squamous cell carcinoma of the nasolacrimal duct. In the sixth and seventh patients, mesh was used to reconstruct the nasal bridge after severely comminuted nasal fractures resulted in the loss of bone and mucosa. Finally, the eighth patient had titanium mesh used to replace cocaine-induced bone loss involving the left medial orbital floor and wall and part of the maxilla. On gross examination by either endoscopy or direct inspection, all eight patients had rapid soft-tissue incorporation of the titanium mesh. Initial examination typically revealed budding of soft tissue through mesh interstices, followed by progressive incorporation. One patient's mesh was covered in only 15 days. Two patients underwent biopsies of this newly formed soft tissue. One had biopsies performed at 3, 15, and 31 months after the original operation. Biopsy examination at 3 months revealed incorporation of the titanium with fibrous soft tissue covered by ciliated respiratory epithelium, goblet cells, and squamous epithelium with metaplasia. In addition, the dense, acute inflammation present at 3 months evolved into mild, chronic inflammation at 31 months. The second patient had a single biopsy 4 months after secondary orbital reconstruction for delayed enophthalmos. Biopsy examination revealed a fibrous soft-tissue sheath lined by squamous epithelium with metaplasia. Again, mild chronic inflammation was present within the soft tissue. This study provides evidence of titanium's compatibility with soft tissue. The mesh underwent progressive incorporation with soft tissue that was then resurfaced by indigenous cells, including respiratory epithelia and goblet cells. This phenomenon occurred despite communication with the nasal-oral-pharyngeal area and paranasal sinuses.  相似文献   

5.
Two-dimensional electrophoresis on cellulose acetate membrane permits the clean separation of sulfated glycopeptide in a mixture of acidic glycans (glycosaminoglycans and acidic glycopeptides). Two systems were used. In system 1, 0.1 M pyridine-0.47 M formic acid buffer (pH 3.0) was used in the first and 0.1 M barium acetate (pH 8.0) in the second dimension. In system 2, 0.1 M pyridine-0.47 M formic acid buffer (pH 3.0) was used in the first and 0.1 M HCl in the second dimension. All of the acidic glycans on electrophoretogram were stained with alcian blue in 70% ethanol. On the other hand, sulfated glycans alone were made visible with alcian blue in 0.1 M HCl. Alcian blue in 70% ethanol or 0.1 M HCl, when combined with periodic acid-Schiff's reagent identified sulfated glycopeptides on cellulose acetate membrane.  相似文献   

6.
Evidence for the presence of a sulfated polysaccharide component within the extracellular matrix of Platydorina caudata Kofoid is presented. In situ staining with alcian blue and toluidine blue O indicates accumulation of a sulfated polysaccharide in the matrix. The entire matrix was readily solubilized by a hot aqueous extraction and a sulfated proteoglycan complex was isolated. Thin-layer chromatography of hydrolysates and infrared analysis and chemical desulfation of the intact molecule indicate that the polysaccharide component is principally an arabinogalactan with ester-linked sulfate groups. Protease treatment of the extract revealed two distinct bands separable on cellulose acetate electrophoresis. The slower moving component was a sulfated glycoprotein while the faster moving component was a sulfated mucopolysaccharide essentially free of protein. This is the first report of specific chemical analyses and electrophoretic separation of a sulfated polysaccharide within the matrix of a member of the Volvocales. The cytochemistry and electrophoretic patterns of the P. caudata preparation are compared with the same type of extract made from Chlamydomonas reinhardtii Dang. The possible evolutionary significance of the electrophoretic patterns is presented.  相似文献   

7.
《Process Biochemistry》2007,42(2):188-192
Fractionation of fibrous fraction from steam-exploded rice straw (SERS) of high moisture content have been studied with respect to the separation degree of fibrous tissue from non-fibrous tissue including epidermal, parenchymatous and vessel tissue using a fluidized bed opposed jet mill. Chemical composition and fiber characteristics, such as fiber size and composed cell proportion were studied for the separated fibrous fraction of SERS. 70.4% high cellulose fibrous fraction with 63.1% fiber cell content and 65.6% cellulose content was produced from the fractionation process. The separation degree of fibrous tissue of the fractionated fibrous fraction was 2.04. The mean fiber length was 0.97 mm, slightly longer than the untreated rice straw. The new method is suitable to produce high fiber tissue content fractions without damaging the raw fibers extensively.  相似文献   

8.
Artificial membranes composed of mixed cellulose nitrate and acetate esters (MCEM), polytetrafluoroethylene (Mitex), cellulose acetate (Celotate), polyvinylchloride (Polyvic), polycarbonate (Nuclepore), or linear polyethylene with pore sizes ranging from 0.45 mu to 70 mu were coated on their inner surfaces with a paste of bone marrow, diaphyseal bone, or cells proliferating in vitro on the inner surfaces of curetted femurs obtained from syngeneic mice. Squares of these membranes were folded into thirds, stapled to form an open-ended, tube-like structure, and implanted i.p. into mice. At intervals of 6-12 months, the membranes were removed and studied histologically. Control membranes not coated with any substance were also studied. Trilineal hematopoiesis, bone formation, sinusoidal structures, fat cells, and hemosiderin-laden macrophages were found with all three coatings in the tubes formed from the MCEM or Mitex membranes. The Celotate and Polyvic membranes coated with bone cells and the Polyvic membranes coated with marrow also developed trilineal hematopoiesis and new bone tissue. The remaining membranes essentially had only fibrous tissue, except for rare foci of hematopoiesis which developed on an occasional 30 mu (but not 70 mu) pore size linear polyethylene membrane. The results of these studies suggest that hematopoiesis and bone cell formation on these artificial membranes is closely linked, and that there may be some interaction between membrane constituents and the cells destined to form the hematopoietic support layer in the fostering of hematopoiesis. Whether this interaction is stimulatory or inhibitory was not defined by these studies.  相似文献   

9.
Cellulose-binding protein A (CbpA), a component of the cellulase complex of Clostridium cellulovorans, contains a unique sequence which has been demonstrated to be a cellulose-binding domain (CBD). The DNA coding for this putative CBD was subcloned into pET-8c, an Escherichia coli expression vector. The protein produced under the direction of the recombinant plasmid, pET-CBD, had a high affinity for crystalline cellulose. Affinity-purified CBD protein was used in equilibrium binding experiments to characterize the interaction of the protein with various polysaccharides. It was found that the binding capacity of highly crystalline cellulose samples (e.g., cotton) was greater than that of samples of low crystallinity (e.g., fibrous cellulose). At saturating CBD concentration, about 6.4 mumol of protein was bound by 1 g of cotton. Under the same conditions, fibrous cellulose bound only 0.2 mumol of CBD per g. The measured dissociation constant was in the 1 microM range for all cellulose samples. The results suggest that the CBD binds specifically to crystalline cellulose. Chitin, which has a crystal structure similar to that of cellulose, also was bound by the CBD. The presence of high levels of cellobiose or carboxymethyl cellulose in the assay mixture had no effect on the binding of CBD protein to crystalline cellulose. This result suggests that the CBD recognition site is larger than a simple cellobiose unit or more complex than a repeating cellobiose moiety. This CBD is of particular interest because it is the first CBD from a completely sequenced nonenzymatic protein shown to be an independently functional domain.  相似文献   

10.
Neutral cellulose nanocrystals dispersed in water were shown in a previous work to stabilize oil/water interfaces and produce Pickering emulsions with outstanding stability, whereas sulfated nanocrystals obtained from cotton did not show interfacial properties. To develop a better understanding of the stabilization mechanism, amphiphilic properties of the nanocrystals were modulated by tuning the surface charge density to investigate emulsifying capability on two sources of cellulose: cotton linters (CCN) and bacterial cellulose (BCN). This charge adjustment made it possible to determine the conditions where a low surface charge density, below 0.03 e/nm(2), remains compatible with emulsification, as well as when assisted by charge screening regardless of the source. This study discusses this ability to stabilize oil-in-water emulsions for cellulose nanocrystals varying in crystalline allomorph, morphology, and hydrolysis processes related to the amphiphilic character of nonhydrophobized cellulose nanocrystal.  相似文献   

11.
K Yamasaki 《Jikken dobutsu》1986,35(4):499-500
Aspiration pneumonia observed in eight of 60 Sprague-Dawley rats which were orally treated with 0.5% carboxymethyl cellulose solution was investigated. Grossly, the lung showed white nodular foci in the parenchyma. Histologically, changes were characterized by fibrous material accompanied by inflammatory cells in the alveoli and bronchioles and formation of granulomas. It appeared that the inhaled fibrous material had originated from the carboxymethyl cellulose solution.  相似文献   

12.
Gabara  Barbara 《Protoplasma》1975,86(1-3):159-168
Summary It was shown that Golgi structures abundantly appearing in tapetal cells ofDelphinium Ajacis L. developing anthers, prior to meiocytes meiosis, show a fine fibrous material within their vesicles. At the time of the formation of tapetal cell wall this fibrous component, released by an exocytotic process, is incorporated into the cell wall. The membrane of dictyosomes derived vesicles participates in the development of plasma membrane. Fibrous material appears to be morphologically similar to the fibrils of tapetal cell wall; this cell wall gives a positive reaction for cellulose and pectins, as visible in the light microscope. Moreover, the fibrous and pectinase resistant compound of dictyosomes derived vesicles and the fibrils of cell wall disappear partly after cellulase digestion which proves their cellulosic character. On the other hand pectinase treatment as well as ruthenium red staining suggest associated with cellulose pectins within Golgi vesicles.  相似文献   

13.
In our previous paper, we reported that various types of carrageenan, dextran sulfate and fucoidan, which are sulfated homopolysaccharides with high molecular weights, were human T cell mitogens and murine polyclonal B cell activators (PBAs) and that heparin, a sulfated heteropolysaccharide, was a very weak human mitogen and mouse PBA. Here we used cellulose sulfate (Mr 7-9 X 10(3], dextran sulfate with two different low molecular weights (Mr 5 X 10(3) and 8 X 10(3], two different condroitin sulfates (Mr 3.5 X 10(4], polyvinyl sulfate and polygalacturonic acid to investigate mitogenic activities of polysaccharides in detail. The following results were obtained. Low-molecular-weight sulfated homopolysaccharides, dextran sulfate and cellulose sulfate, were very weak or not human T cell mitogens. However, they were better murine PBAs. Sulfated heteropolysaccharides, chondroitin 4-sulfate and chondroitin 6-sulfate, hardly induced mitogenic changes in human T cells and mouse B cells, even though the molecular weight of these substances was more than 1 X 10(4). There were no other polymers examined so far which activated both human T cells and murine B cells. The relationship among molecular size, sulfate groups and lymphocyte activation is discussed in detail.  相似文献   

14.
Isolated mouse osteoblasts that retain their osteogenic activity in culture were incubated with [35S] sulfate. Two radiolabeled proteins, in addition to proteoglycans, were extracted from the calcified matrix of osteoblast cultures. All the sulfate label in both proteins was in the form of tyrosine sulfate as assessed by amino acid analysis and thin layer chromatography following alkaline hydrolysis. The elution behavior on DEAE-Sephacel of the major sulfated protein and the apparent Mr on sodium dodecyl sulfate gels were characteristic of bone sialoprotein II extracted from rat. This protein was shown to cross-react with an antiserum raised against bovine bone sialoprotein II, indicating that bone sialoprotein II synthesized by cultured mouse osteoblasts is a tyrosine-sulfated protein. The minor sulfated protein was tentatively identified as bone sialoprotein I or osteopontin based on its elution properties on DEAE-Sephacel and anomalous behavior on sodium dodecyl sulfate gels similar to those reported for rat bone sialoprotein I.  相似文献   

15.
Rabbit platelets were labeled in vivo with 35S for characterization of platelet sulfated glycosaminoglycan. When rabbit platelets were aggregated by ADP, sulfated proteoglycan was lost from the platelet surface although no release of granule contents occurred. The sulfated proteoglycan contained in the granules of platelets pretreated with ADP was subsequently released by treatment with thrombin. The 35S-labeled proteoglycan from both sources was isolated by gel filtration and the glycosaminoglycan portion of the proteoglycan was characterized as chondroitin 4-sulfate by examining the products of digestion with hyaluronidase, chondroitinase AC and ABC, and chondro-4- and 6-sulfatases; by identification of the hexosamine as N-acetylgalactosamine; by determination of a 1 : 1 : 1 molar ratio of N-acetylgalactosamine, uronic acid and inorganic sulfate; and by cetylpyridinium chloride cellulose chromatography. In these studies, the use of 35S-labeled proteoglycan made possible detection and quantification of much smaller amounts of material than would be possible with unlabeled material. Chondroitin 4-sulfate was the only sulfated glycosaminoglycan identified in the proteoglycan lost from the platelet surface during ADP-induced aggregation and in the proteoglycan released from the granules when the platelets were exposed to thrombin.  相似文献   

16.
A method is described for the separation and assay of radiolabeled glycosaminoglycuronans (GAGs) from cell culture medium. Following papain digestion and precipitation with cetylpyridinium chloride onto cellulose ester filter membrane, hyaluronic acid can be separated from sulfated GAGs by selective elution with HCl.  相似文献   

17.
Photosynthetic aquatic species, i.e., micro- and macroalgae and fresh or salt water plants, contain cellulose or other fibrous materials potentially suitable for paper making. Photosynthetic aquatic species having cellulosic or fibrous characteristics necessary for paper production were reviewed. These characteristics include overall fiber content, fiber size and morphology, and fiber composition. Several species of algae and aquatic plants are reported to possess cellulose in quantities greater than 10 % of total dry weight, and in general, the cellulose content in aquatic species is lower than that of most wood species. Commercial application of these aquatic algal or plant materials has been limited to simple milling, and no commercial applications utilizing processes to isolate the cellulosic fibers from these materials have yet been found.  相似文献   

18.
Estrogen plays an important role in maintaining bone density. Postmenopausal women have low plasma estrogen, but have high levels of conjugated steroids, particularly estrone sulfate (E1S) and dehydroepiandrosterone sulfate (DHEAS). Conversion of these precursors to active estrogens may help maintain bone density in postmenopausal women. The enzyme steroid sulfatase (STS) converts sulfated steroids into active forms in peripheral tissues. STS occurs in bone, but little is known about its role in bone function. In this study, we investigated STS activity and expression in the human MG-63 pre-osteoblastic cell line. We also tested whether sulfated steroids can stimulate growth of these cells. MG-63 cells and microsomes both possessed STS activity, which was blocked by the STS inhibitors EMATE and 667 Coumate. Further evidence for STS in these cells was provided by RT-PCR, using STS specific primers, which resulted in cDNA products of the predicted size. We then tested for growth of MG-63 cells in the presence of estradiol-17β, E1S and DHEAS. All three steroids stimulated MG-63 cell growth in a steroid-free basal medium. We also tested whether the cell growth induced by sulfated steroids could be blocked using a STS inhibitor (667 Coumate) or using an estrogen receptor blocker (ICI 182,780). Both compounds inhibited E1S-induced cell growth, indicating that E1S stimulates MG-63 cell growth through a mechanism involving both STS and the estrogen receptor. Finally, we demonstrated using RT-PCR that MG-63 cells contain mRNA for both estrogen receptor alpha and estrogen receptor beta. Our data reveal that STS is present in human pre-osteoblastic bone cells and that it can influence bone cell growth by converting inactive sulfated steroids to estrogenic forms that act via estrogen receptor alpha or beta.  相似文献   

19.
Solid acid and microwave-assisted hydrolysis of cellulose in ionic liquid   总被引:2,自引:0,他引:2  
Solid acid-catalyzed hydrolysis of cellulose in ionic liquid was greatly promoted by microwave heating. H-form zeolites with a lower Si/Al molar ratio and a larger surface area showed a relatively higher catalytic activity. These solid catalysts exhibited better performance than the sulfated ion-exchanging resin NKC-9. Compared with conventional oil bath heating mode, microwave irradiation at an appropriate power significantly reduced the reaction time and increased the yields of reducing sugars. A typical hydrolysis reaction with Avicel cellulose produced glucose in around 37% yield within 8 min.  相似文献   

20.
The present study has applied the low iron diamine (LID) method at the ultrastructural level to demonstrate acid glycoconjugates. We have examined rat epiphyseal cartilage, human bone marrow, rat tracheal glands, and mouse sublingual glands stained with LID prior to embedment. The LID staining appeared to require postosmication for adequate visualization at the electron microscope level. Thiocarbohydrazide-silver proteinate (TCH-SP) staining of thin sections variably enhanced LID reactive sites. LID-TCH-SP stained carboxyl and sulfate groups of glycosaminoglycans in the extracellular cartilage matrix, secretory granules, and expanded Golgi saccules of chondrocytes. In human bone marrow, LID-TCH-SP variably stained the cytoplasmic granules, known to contain sulfated glycosaminoglycans, and the external surface of the plasma membrane of leukocytes. Moderately strong LID staining was observed in secretory granules in mucous tubules of rat tracheal glands, known to contain sulfated glycoproteins, and in acinar cells of mouse sublingual glands, known to contain a sialoglycoprotein. The lack of sulfated glycoconjugates in acinar cells of the mouse sublingual gland was confirmed by their failure to stain with the high iron diamine method. Thus these studies indicate that the LID and LID-TCH-SP methods are useful for the ultrastructural localization of carboxylated and sulfated glycoconjugates in extracellular and intracellular sites.  相似文献   

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