To see the other types of publications on this topic, follow the link: Sulphate released.
Journal articles on the topic 'Sulphate released'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Sulphate released.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Ahuja, K. K., and D. J. Gilburt. "Involvement of sperm sulphatases in early sperm-zona interactions in the hamster." Journal of Cell Science 78, no. 1 (1985): 247–61. http://dx.doi.org/10.1242/jcs.78.1.247.
Full textAbstract:
Sulphatase preparations from Abalone entrails, the limpet Patella vulgata and ox liver, as well as artificial substrates for these enzymes, were used in the hamster in vitro fertilization system to study the possible roles of sperm sulphatases in sperm-zona pellucida interactions. p-nitrophenyl sulphate, p-nitrocatechol sulphate, ascorbate 2-sulphate, as well as D-glucopyranose and D-galactopyranose, both sulphated at the 3, 4 or 6 position but not the 2 position, inhibited fertilization in a dose-dependent manner. Sperm-egg fusion was not inhibited by the substrates used and eggs pre-treated with sulphates could readily be fertilized. Sperm motility and therefore viability was unaffected by inhibitory concentrations of substrates as determined by rhodamine 123 labelling of motile spermatozoa. Acrosomal integrity of rhodamine-labelled spermatozoa was assessed and found to be unaffected by inhibitory levels of substrates. Fertilization was inhibited by high concentrations of the two molluscan sulphatases but not by purified ox liver sulphatase. Pre-treatment of eggs with these enzymes did not prevent fertilization. Long-term exposure of hamster oocytes to N-acetylhexosaminidase or limpet sulphatase caused thinning and distension of the zona pellucida but these changes were not observed with the ox liver sulphatase. The results suggest that a glycosulphatase is probably released from hamster spermatozoa during sperm-egg adhesion and, or, penetration. If sperm-egg adhesion molecules are sulphated, the commercially available sulphatases would be unsuitable for their characterization.
2
Han, J. R., and M. C. Liu. "Polarized secretion of tyrosine-sulphated proteins and free tyrosine O-sulphate by filter-grown Madin-Darby canine kidney (MDCK) cells." Biochemical Journal 279, no. 1 (1991): 289–95. http://dx.doi.org/10.1042/bj2790289.
Full textAbstract:
Filter-grown Madin-Darby canine kidney (MDCK) cells labelled for 24 h with [35S]sulphate were found to secrete macromolecules [35S]sulphated on their carbohydrate moieties predominantly into the basolateral medium, whereas the tyrosine-[35S]sulphated proteins synthesized were predominantly secreted into the apical medium. In contrast with the predominant apical secretin of tyrosine-[35S]sulphated proteins, the free tyrosine O-[35S]sulphate (Tyr[35S]) was released mostly into the basolateral medium. A time-lapse study using prelabelled MDCK cells incubated in fresh medium revealed that, during the 48 h time course monitored, the release of tyrosine-[35S]sulphated proteins into the apical medium was faster and quantitatively greater than that into the basolateral medium. During the same time there was a concomitant release, predominantly into the basolateral medium, of the free Tyr[35S] derived from the degradation of tyrosine-[35S]sulphated proteins. An endocytotic degradation experiment was performed to demonstrate the endocytosis of tyrosine-sulphated proteins and their degradation to generate free TyrS. It was found that free Tyr[35S] was generated and released when an apically secreted (or basolaterally secreted) tyrosine-[35S]sulphated protein preparation was added to the apical medium (or the basolateral medium) of unlabelled filter-grown MDCK cells. In both cases, the free Tyr[35S] generated was predominantly released into the basolateral medium similar to the results obtained in the time-lapse study.
3
Liu, M. C., M. Suiko, and F. Lipmann. "Rapid catabolism of tyrosine-O-sulphated proteins and the formation of free tyrosine O-sulphate as an end product in rat embryo fibroblasts." Biochemical Journal 243, no. 2 (1987): 555–59. http://dx.doi.org/10.1042/bj2430555.
Full textAbstract:
Rat embryo fibroblasts, line 3Y1, were prelabelled for 24 h with [35S]sulphate and incubated in fresh medium without [35S]sulphate. A rapid efflux of the overall 35S-labelled compounds from the cells into the medium was observed. After 9 h of incubation, about 50% of the total 35S radioactivity appeared in the medium and up to 84.3% did so at the end of a 48 h incubation. Determination of [35S]sulphated macromolecules present in both the cell-associated and the incubation-medium fractions at different time points during incubation indicated that the majority of the 35S-labelled compounds released from the cells were low-Mr products derived from digestion of the [35S]sulphated macromolecules. Further analysis for tyrosine-O-[35S]sulphated proteins, which constituted only a small fraction of the overall [35S]sulphated macromolecules, showed that, after 9 h of incubation, there was a 65% decrease in the cell-associated fraction, and only 16.4% remained after 48 h. During that time, an amount equivalent to 20.7% of the cell-associated tyrosine-O-[35S]sulphated proteins originally present was released into the medium. Free tyrosine O-[35S]sulphate was generated in the cells and excreted into the incubation medium. Its rate of increase with time, however, was slow, and could account for only 12.4% of the tyrosine-O-[35S]sulphated proteins catabolized at the end of the 48 h incubation.
4
Whiteley, C. G., X. Melamane, B. Pletschke, and P. D. Rose. "The enzymology of sludge solubilisation utilising sulphate reducing systems: the role of lipases." Water Science and Technology 48, no. 8 (2003): 159–67. http://dx.doi.org/10.2166/wst.2003.0465.
Full textAbstract:
The first stage in the degradation and recycling of particulate organic matter is the solubilisation and enhanced hydrolysis of complex polymeric organic carbon structures associated with the sulphidogenic environment. An investigation into the enzymology of these processes has shown that lipase enzyme activities were found predominantly associated with the organic particulate matter of the sewage sludge. Sonication of the sludge gave an increase in enzyme activity as the enzymes were released into the supernatant. pH and temperature optimisation studies showed optima at between 6.5 and 8 and 50-60°C, respectively. All the lipase enzymes from the methanogenic bioreactors indicated extensive stability for at least an hour at their respective optimum temperatures and pH; sulphidogenic lipases reflected limited stability at these temperatures and pH during this time period. Though sulphate showed inhibitory properties towards lipases both sulphide and sulphite appeared to enhance the activity of the enzymes. It is argued that these sulphur species, liberated at different times during the sulphate reduction process, disrupt the integrity of the organic particulate floc by neutralising acidic components on the surface. The release of further entrapped enzymes from the organic particulate matter results in a subsequent enhancement of hydrolysis of polymeric material.
5
Cortés-Hernández, Dora A., Luis A. Bretado-Aragón, W. Ortega-Lara, David Rentería-Zamarrón, and Y. Salinas-Delgado. "Gentamicin Sulphate Release from Bioactive Ceramic Calcium Silicates." Key Engineering Materials 396-398 (October 2008): 527–30. http://dx.doi.org/10.4028/www.scientific.net/kem.396-398.527.
Full textAbstract:
Gentamicin sulphate was mixed with two different sol-gel derived calcium silicates (akermanite or wollastonite). Each of the mixtures was isostatically pressed. Samples were immersed in simulated body fluid for 21 days. The presence of the antibiotic showed no effect on the in vitro bioactivity of the ceramics. For evaluating the gentamicin sulphate release, samples were immersed in a phosphate buffered saline solution for different periods of time. Most of the gentamicin sulphate was released during the first 7 days. However, akermanite showed a lower antibiotic release rate than that observed for wollastonite.
6
Lindblom, A., G. Bengtsson-Olivecrona, and L. A. Fransson. "Domain structure of endothelial heparan sulphate." Biochemical Journal 279, no. 3 (1991): 821–29. http://dx.doi.org/10.1042/bj2790821.
Full textAbstract:
The domain structure of heparan sulphate chains from an endothelial low-density proteoglycan was examined using specific degradations of the chains while attached to the intact proteoglycan. ‘Inner’ chain fragments, remaining on the protein core, were separated from ‘outer’ fragments by gel chromatography, and were subsequently released from the protein core by alkaline cleavage. The structure of ‘inner’ and ‘outer’ chain fragments was then examined and compared. Using deaminative cleavage we obtained evidence that the first N-sulphated glucosamine residue is variably positioned some 10-17 disaccharides from the xylose-serine linkage of the proteoglycan. Digestion with heparinase yielded ‘inner’ and ‘outer’ fragments covering a broad range of different sizes, indicating a scarce and variable distribution of sulphated iduronic acid in the native chains. N-sulphated glucosamine occurred more frequently in the ‘outer’ fragments. We also studied the affinity of the endothelial heparan sulphate chains towards two presumptive biological ligands, namely antithrombin III and lipoprotein lipase. A major part of the endothelial heparan sulphate chains showed a weak affinity for antithrombin III and the affinity was essentially lost on heparinase digestion. On lipoprotein lipase-agarose the endothelial heparan sulphate chains were eluted at the same salt concentration as heparin, and the binding persisted, although with decreased strength, after digestion with heparinase.
7
Jacobsen, Tomas, Bo Jensen, Jørgen Olsen, and Knud Allermann. "Preparation of protoplasts from mycelium and arthroconidia of Geotrichum candidum." Canadian Journal of Microbiology 31, no. 2 (1985): 93–96. http://dx.doi.org/10.1139/m85-019.
Full textAbstract:
Protoplasts were released from mycelium and the cylindrical type of arthroconidia from Geotrichum candidum by a lytic enzyme (Novozym 234). This enzyme was unable to release protoplasts from the ellipsoidal type of arthroconidia, which reflects a difference in the cell walls of the two types of conidia. The conditions necessary to obtain stable protoplasts were determined. Magnesium sulphate (0.8 M) was the best osmotic stabilizer for the formation of protoplasts, whereas both mannitol and magnesium sulphate could be used for regeneration. The regeneration was faster with mannitol than with magnesium sulphate.
8
Hewitt, C. Nicholas, and Brian Davison. "Field measurements of dimethyl sulphide and its oxidation products in the atmosphere." Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences 352, no. 1350 (1997): 183–89. http://dx.doi.org/10.1098/rstb.1997.0013.
Full textAbstract:
Dimethyl sulphide (DMS) is released into ocean waters by phytoplankton and may then cross the water–air interface into the atmosphere. Various models have been formulated to describe its behaviour in the atmosphere. Here, measurements of its concentrations and those of its major oxidation products, methane sulphonate, sulphur dioxide, non sea–salt sulphate and demethyl sulphoxide, in both the gas and aerosol phases, in Atlandtic air, are used to validate these qualitative descriptions of its oxidation. Behaviour consistent with day–time oxidation by the hydroxyl radical, with the yield of methane sulphonic acid being both temperature dependent and under the influence of the nitrogen dioxide mixing ratio, is seen. The rapid production of new particles also seems likely under certain conditions but it is not clear whether or not they enhance the concentrations of cloud condensation nuclei in the maritime troposphere. In maritime air a substantial fraction of the sulphate formed appears to be neutralized by reaction with ammonia to form ammonium aerosol.
9
Krusius, T., V. N. Reinhold, R. K. Margolis, and R. U. Margolis. "Structural studies on sialylated and sulphated O-glycosidic mannose-linked oligosaccharides in the chondroitin sulphate proteoglycan of brain." Biochemical Journal 245, no. 1 (1987): 229–34. http://dx.doi.org/10.1042/bj2450229.
Full textAbstract:
We have previously described the structures of neutral and sialylated O-glycosidic mannose-linked tetrasaccharides and keratan sulphate polysaccharide chains in the chondroitin sulphate proteoglycan of brain. The present paper provides information on a series of related sialylated and/or sulphated tri- to penta-saccharides released by alkaline-borohydride treatment of the proteoglycan glycopeptides. The oligosaccharides were fractionated by ion-exchange chromatography and gel filtration, and their structural properties were studied by methylation analysis and fast-atom-bombardment mass spectrometry. Five fractions containing [35S]sulphate-labelled oligosaccharides were obtained by ion-exchange chromatography, each of which was eluted from Sephadex G-50 as two well-separated peaks. The apparent Mr values of both the large- and small-molecular-size fractions increased with increasing acidity (and sulphate labelling) of the oligosaccharides. The larger-molecular-size fractions contained short mannose-linked keratan sulphate chains of Mr 3000-4500, together with some asparagine-linked oligosaccharides. The smaller tri- to penta-saccharides, of Mr 800-1400, appear to have a common GlcNac(beta 1-3)Manol core, and to contain one to two residues of sialic acid and/or sulphate.
10
Okayama, M., K. Oguri, Y. Fujiwara, et al. "Purification and characterization of human platelet proteoglycan." Biochemical Journal 233, no. 1 (1986): 73–81. http://dx.doi.org/10.1042/bj2330073.
Full textAbstract:
Freshly prepared platelets were shown to contain glycosaminoglycans equivalent to 530 micrograms of hexuronate/10(11) platelets. When the platelets were extracted with 4 M-guanidinium chloride containing proteinase inhibitors, and the extract was dialysed extensively against 7 M-urea solution, almost all of proteoglycan was recovered in the urea-soluble fraction. The proteoglycan was purified from the urea-soluble fraction with a yield of 47% by DEAE-Sephacel chromatography, CsCl-density-gradient centrifugation, Bio-Gel A-15m gel filtration and then rechromatography on DEAE-Sephacel. The purified proteoglycan contained 30% glucuronic acid, 32% N-acetylgalactosamine, 14% sulphate and 15% protein. Serine, glutamic acid, glycine, aspartic acid and leucine accounted for 64% of the total amino acids. The Mr of the proteoglycan was assessed to be approx. 136000 by sedimentation-equilibrium methods. The galactosaminoglycan released by alkaline-borohydride treatment of the proteoglycan was converted stoichiometrically into 4-sulphated unsaturated disaccharide by digestion with chondroitinase AC-II, indicating that the galactosaminoglycan was fully sulphated chondroitin 4-sulphate. The apparent Mr of the chondroitin sulphate was assessed to be 28000 by gel filtration on Bio-Gel A-0.5m (KD 0.18). On two-dimensional electrophoresis on a cellulose acetate membrane, the chondroitin sulphate gave a single compact spot co-migrating with a reference chondroitin sulphate, indicating that the chondroitin sulphate chains were homogeneous in both length and charge density. On the basis of these results, the proteoglycan in human platelets was concluded to be a macromolecule of Mr 136000 containing four chondroitin 4-sulphate chains each with the apparent Mr of 28000.
11
Beavan, L. A., M. Davies, and R. M. Mason. "Renal glomerular proteoglycans. An investigation of their synthesis in vivo using a technique for fixation in situ." Biochemical Journal 251, no. 2 (1988): 411–18. http://dx.doi.org/10.1042/bj2510411.
Full textAbstract:
Newly synthesized rat glomerular [35S]proteoglycans were labelled in vivo after injecting Na2[35S]SO4 intraperitoneally. At the end of the labelling period (7 h) the kidneys were perfused in situ with 0.01% (w/v) cetylpyridinium chloride. This fixed proteoglycans in the tissue and increased their recovery 2-3-fold during subsequent isolation of glomeruli from the renal cortex. The glomeruli were fractionated by a modified osmotic lysis and detergent extraction procedure [Meezan, Brendel, Hjelle & Carlson (1978) in The Biology and Chemistry of Basement Membranes (Kefalides, N.A., ed.), Academic Press, New York; Kanwar & Farquhar (1979) Proc. Natl. Acad. Sci. U.S.A. 76, 4493-4497] to obtain a basement membrane preparation. The proteoglycans released at each stage of the procedure were characterized using DEAE-Sephacel ion-exchange chromatography, chondroitinase ABC and HNO2 digestion and Sepharose CL-4B gel-permeation chromatography. About 85% of the [35S]proteoglycans synthesized were of the heparan sulphate variety, the remainder being chondroitin sulphate proteoglycans. Three sizes of heparan sulphate proteoglycans were identified. The largest (HS1, Kav. 0.47) accounts for 44% of the total extractable heparan sulphates. About one third of HS1 were extracted from the glomerular basement-membrane fraction with 8 M-urea and 4 M-guanidine hydrochloride but the remainder were released from the glomerulus during preparation of the fraction. The two smaller molecules (HS2, Kav. 0.56 and HS3, Kav. 0.68) accounted for 27% and 28% of the extractable heparan sulphate respectively and were not associated with the basement membrane fraction. HS1, HS2 and HS3 were also isolated from non-fixed glomeruli labelled in vivo but with much lower recovery. In glomeruli labelled in vitro, heparan sulphate accounted for only 35% of the proteoglycans, the remainder being of the chondroitin sulphate type. Proteoglycans similar to HS1, HS2 and HS3 were present in glomeruli labelled in vitro but, in addition, a large, highly charged heparan sulphate (HS1a) was extracted from the glomerular basement-membrane fraction of these glomeruli. It accounted for 6% of the total heparan sulphate.
12
Wang, Guang Yuan, Xing Yu Liu, Qi Yuan Gu, Ming Jiang Zhang, and Jian Kang Wen. "The Effect of Ammonium Sulfate on the Sulphate Reducing Bacteria Bio-Derived Material." Key Engineering Materials 723 (December 2016): 529–33. http://dx.doi.org/10.4028/www.scientific.net/kem.723.529.
Full textAbstract:
The lead-zinc tailings, a kind of hazardous wastes, containing large amount of heavy metals with high extraction toxicity, which would be released into solution with water, oxygen, microorganism and make the environment contaminated. Sulfide ion and alkaline substance were produced with the growth and anaerobic metabolism of sulphate reducing bacteria, inhibiting the oxidation and release of heavy metal ions from the lead-zinc tailings. Sulphate reducing bacteria attached on the calcined activated carbon while growing in the nutrient solution, which could be used to decline heavy metal ions as bio-derived material. Inorganic nitrogen source could be used by autotrophic bacteria effectively and was negative for the sulphate reducing bacteria to deposit toxic elements in the solution.
13
Honda, A., S. Kazuno, Y. Mori, K. Kimata, and S. Suzuki. "Altered proteoglycan synthesis by micromelial limbs induced by 6-aminonicotinamide. Appearance of abnormal forms of cartilage-characteristic proteoglycan (PG-H)." Biochemical Journal 246, no. 3 (1987): 745–53. http://dx.doi.org/10.1042/bj2460745.
Full textAbstract:
Since administration of 6-aminonicotinamide (10 micrograms) to day-4 chick embryos in ovo was shown to induce micromelial limbs, biosynthesis of cartilage-characteristic proteoglycan-H (PG-H) as an important index of limb chondrogenesis was examined in day-7 normal and micromelial hind limbs by biochemical and immunological methods. (1) Metabolic labelling of the micromelial limbs with [6-3H]glucosamine and either [35S]sulphate or [35S]methionine, followed by analyses of labelled PG-H by glycerol density-gradient centrifugation under dissociative conditions, showed a marked reduction in the PG-H synthesis. (2) PG-H synthesized by the micromelial limbs was much lower than that synthesized by the normal limbs in the biosynthetic ratio of chondroitin sulphate to keratan sulphate and glycoprotein-type oligosaccharide, although no significant difference was observed in the immunological properties of these proteoglycans. (3) The degree of sulphation of chondroitin sulphates of PG-H was lowered in the micromelial limbs as judged by the increase of unsulphated disaccharide (delta Di-OS) released by chrondroitinase ABC digestion, although there were no significant differences between the normal and the micromelial limbs in the average molecular size (Mr = 38,000) of labelled chondroitin sulphates of PG-H. (4) Addition of beta-D-xyloside, an artificial initiator for chondroitin sulphate synthesis, to the micromelial limbs in culture recovered the incorporation of labelled glucosamine into chondroitin sulphate to that comparable with the normal control with beta-D-xyloside, although the incorporation of [35S]sulphate was lower in the micromelia than in the control with beta-D-xyloside. These results suggest that the reduction in the biosynthesis of the PG-H as well as the production of altered forms of PG-H induced by 6-aminonicotinamide during a critical period of limb morphogenesis may be an important factor for the micromelia.
14
Bingman, V., S. Alyan, and S. Benvenuti. "The importance of atmospheric odours for the homing performance of pigeons in the sonoran desert of the southwestern united states." Journal of Experimental Biology 201, no. 5 (1998): 755–60. http://dx.doi.org/10.1242/jeb.201.5.755.
Full textAbstract:
The importance of atmospheric odours for homing pigeon navigation in a desert environment was tested using birds from two lofts located in the Sonoran desert near Tucson, Arizona, USA. When released from a familiar training site, experienced control pigeons and pigeons given intranasal injections of zinc sulphate to produce anosmia both displayed good homeward orientation and homed rapidly. When released from two unfamiliar locations, in contrast, the controls continued to display good homing performance while the zinc-sulphate-treated pigeons homed poorly. Significant differences in vanishing bearings, homing time and homing success were recorded. When a group of control and a group of zinc-sulphate-treated inexperienced pigeons were released from two unfamiliar locations, both groups homed poorly. Nonetheless, the controls still outperformed the zinc-sulphate-treated birds, the most notable result being a significant difference in homing success. Taken together, these results highlight the importance of atmospheric odours for the operation of the navigational map of the homing pigeon in a desert environment and, together with previous experiments, demonstrate that the role of atmospheric odours in homing does not seem to vary in any salient way with ambient climatic conditions. <P>
15
Sjöberg, E. M., and E. Fries. "One of the major sulphated proteins secreted by rat hepatocytes contains low-sulphated chondroitin sulphate." Biochemical Journal 272, no. 1 (1990): 113–18. http://dx.doi.org/10.1042/bj2720113.
Full textAbstract:
When isolated hepatocytes are incubated with 35SO4(2-), a specific set of secretory proteins is labelled. One of these proteins is electrophoretically heterogeneous, with an apparent molecular mass of 35-45 kDa [Marcks von Würtemberg & Fries (1989) Biochemistry 28, 4088-4093]. Here we report that treatment with chondroitinase ABC converted the broad electrophoretic band of this protein, with a 50-60% loss of radioactivity, into a relatively homogeneous band with a molecular mass of 28 kDa. Size determination by gel chromatography of the protein's oligosaccharide chain (released by alkali treatment) indicated that it contained about 40 hexose units. Similar analysis of the enzyme-resistant oligosaccharide chain remaining linked to the protein after chondroitinase ABC treatment indicated a size of between six and eight hexose units. These observations suggest that the protein's oligosaccharide chain carries only three or four sulphate groups, of which one or two are located close to the polypeptide chain. Consistent with this hypothesis, the free oligosaccharide behaved like a low-sulphated glycosaminoglycan upon ion-exchange chromatography.
16
Ratcliffe, A., J. A. Tyler, and T. E. Hardingham. "Articular cartilage cultured with interleukin 1. Increased release of link protein, hyaluronate-binding region and other proteoglycan fragments." Biochemical Journal 238, no. 2 (1986): 571–80. http://dx.doi.org/10.1042/bj2380571.
Full textAbstract:
Pig articular cartilage was maintained in culture for 3 days with and without porcine interleukin 1. The proteoglycans remaining in the cartilage and those released into the medium were analysed by using radioimmunoassays for the hyaluronate-binding region, link protein and keratan sulphate. In interleukin 1-treated cultures after 3 days there was 38% release of total glycosaminoglycans into the medium, 18% release of binding region, 14% release of link protein and 20% release of keratan sulphate epitope, whereas in control cultures the proportions released were much less (16, 9, 10 and 7% respectively). Characterization of the proteoglycans in the media after 1.5 days and 3 days of culture showed that interleukin 1 promoted the release of proteoglycan of large average size and also the release of link protein and of low-Mr binding region which was unattached to proteoglycan. Both the link protein and binding region released were able to bind to exogenously added hyaluronate, whereas the proteoglycan in the medium was not. The proteoglycans extracted from cultured cartilage were similar to those from fresh cartilage: they contained a high proportion of aggregating proteoglycans and some low-Mr binding region. The proportion of this binding region extracted from the interleukin 1-treated cartilage was increased. The presence of interleukin 1 in the cultures therefore appeared to increase the rate of proteolytic degradation of proteoglycan in the matrix and to lead to a more rapid loss of intact binding region, of link protein and of large proteoglycan fragments into the medium.
17
Zhang, Dan, Qiang Cheng, and Hui Li. "Setting Behaviors and Ciprofloxacin Hydrochloride Sustained Release of CSH-TCP Binary Cement." Key Engineering Materials 330-332 (February 2007): 1017–20. http://dx.doi.org/10.4028/www.scientific.net/kem.330-332.1017.
Full textAbstract:
Calcium sulphate hemihydrate/α-tricalcium phosphate (CSH-TCP) cement are promising bone replacement materials with controllable-degradation rate and setting time and excellent delivery matrix for sustained release. In the present study, setting behaviors of binary bone cement composed of α-TCP and CSH and release of ciprofloxacin from this cement were investigated in vitro. XRD and SEM results demonstrated that the setting products of CSH-TCP cement were calcium sulphate dihydrate with pillar morphology and hydroxyapatite with needle morphology. Only 20% ciprofloxacin was released from CSH-TCP cement in 7 days in vitro. Fibers of hydroxyapatite enhanced strength of binary cement through fiber-reinforce mechanism. At initial stage (less than 100 hours), the release of ciprofloxacin from CSH-TCP cement was diffusion control, and at subsequent stage the release was matrix dissolution & diffusion control.
18
Rome, L. H., and D. F. Hill. "Lysosomal degradation of glycoproteins and glycosaminoglycans. Efflux and recycling of sulphate and N-acetylhexosamines." Biochemical Journal 235, no. 3 (1986): 707–13. http://dx.doi.org/10.1042/bj2350707.
Full textAbstract:
Lysosomal degradation of the carbohydrate portion of glycoproteins and glycosaminoglycans produces monosaccharides and sulphate, which must efflux from the lysosomes before re-entering biosynthetic pathways. We examined the degradation of glycoproteins and glycosaminoglycans by lysosomes isolated from cultured human diploid fibroblasts. Cells were grown for 24 h in medium containing [3H]glucosamine and [35S]sulphate. When lysosomes are isolated from these cells, they contain label primarily in macromolecules (glycoproteins and glycosaminoglycans). Glycoprotein degradation by isolated lysosomes was followed by measuring the release of tritiated sugars from macromolecules and efflux of these sugars from the organelles. Glycosaminoglycan degradation was monitored by the release of both tritiated sugars and [35S]sulphate. During macromolecule degradation, the total amounts of free [35S]sulphate, N-acetyl[3H]glucosamine and N-acetyl[3H]galactosamine found outside the lysosome parallels the amounts of these products released by degradation. The total degradation of glycoproteins and glycosaminoglycans by intact cultured cells was also examined. The lysosomal contribution to degradation was assessed by measuring inhibition by the lysosomotropic amine NH4Cl. After 48 h incubation, inhibition by NH4Cl exceeded 55% of glycoprotein and 72% of glycosaminoglycan degradation. Recycling of [3H]hexosamines and [35S]sulphate by intact cells was estimated by measuring the appearance of ‘newly synthesized’ radioactively labelled macromolecules in the medium. Sulphate does not appear to be appreciably recycled. N-Acetylglucosamine and N-acetylgalactosamine, on the other hand, are reutilized to a significant extent.
19
Lidholt, K., L. Kjellén, and U. Lindahl. "Biosynthesis of heparin. Relationship between the polymerization and sulphation processes." Biochemical Journal 261, no. 3 (1989): 999–1007. http://dx.doi.org/10.1042/bj2610999.
Full textAbstract:
Incubation of a mouse mastocytoma microsomal fraction with UDP-[3H]GlcA and UDP-GlcNAc yielded proteoglycans containing non-sulphated polysaccharide chains. Similar incubations performed in the presence of sulphate donor 3′-phosphoadenosine 5′-phosphosulphate (PAPS) produced both sulphated and non-sulphated proteoglycans, which were separated by chromatography on DEAE-cellulose Analysis by gel chromatography of single polysaccharide chains, released from the proteoglycans by alkali treatment, showed that the non-sulphated chains produced during incubation for 5 min or 25 min, either in the absence or in the presence of PAPS, were of fairly small molecular size, with an average peak Mr of approx. 10 x 10(3)-15 x 10(3). In contrast, the sulphated chains exceeded Mr 100 x 10(3) Pulse-chase experiments suggested that sulphated chains were capable of further elongation. These results indicate that sulphation promotes, by so far unknown mechanisms, further chain elongation. Sulphated proteoglycan (retarded on DEAE-cellulose chromatography) isolated after similar incubation of the microsomal fraction for 1 min only was found to contain a mixture of sulphated and virtually non-sulphated polysaccharide chains. However, when [35S]PAPS was included in the incubations, some 35S was found to be associated, essentially as N-sulphate groups, also with the latter type of chains, preferentially the high-Mr fraction. These results are interpreted in terms of a biosynthetic model by which the heparin proteoglycan is generated through transient interactions of macromolecular intermediates with distinctly separate complexes of membranebound enzymes.
20
Campbell, M. A., C. J. Handley, and S. E. D'Souza. "Turnover of proteoglycans in articular-cartilage cultures. Characterization of proteoglycans released into the medium." Biochemical Journal 259, no. 1 (1989): 21–25. http://dx.doi.org/10.1042/bj2590021.
Full textAbstract:
By using an e.l.i.s.a. method it was demonstrated that the majority of proteoglycans released into the medium of both control and retinoic acid-treated explant cultures of bovine articular cartilage did not contain a hyaluronate-binding region. This supports our previous findings [Campbell & Handley (1987) Arch. Biochem. Biophys. 258, 143-155] that proteoglycans released into the medium of both cultures were of smaller hydrodynamic size, more polydisperse and unable to form aggregates with hyaluronate. Analysis of 35S-labelled core proteins associated with proteoglycans released into the medium of both cultures by using SDS/polyacrylamide-gel electrophoresis and fluorography indicated the presence of a series of core-protein bands (Mr approx. 300,000, 230,000, 215,000, 200,000, 180,000, 140,000, 135,000, 105,000, 85,000 and 60,000) compared with three core proteins derived from the proteoglycans remaining in the matrix (Mr 300,000, 230,000 and 215,000). Further analysis of the core proteins released into the medium indicated that the larger core proteins associated with medium proteoglycans contain both chondroitin sulphate and keratan sulphate glycosaminoglycans whereas the smaller core proteins contain only chondroitin sulphate chains. These experiments provide definitive evidence that the loss of proteoglycans from the matrix involves proteolytic cleavage at various sites along the proteoglycan core protein.
21
Denger, Karin, Theo H. M. Smits, and Alasdair M. Cook. "L-Cysteate sulpho-lyase, a widespread pyridoxal 5′-phosphate-coupled desulphonative enzyme purified from Silicibacter pomeroyi DSS-3T." Biochemical Journal 394, no. 3 (2006): 657–64. http://dx.doi.org/10.1042/bj20051311.
Full textAbstract:
Quantitative utilization of L-cysteate (2-amino-3-sulphopropionate) as the sole source of carbon and energy for growth of the aerobic, marine bacterium Silicibacter pomeroyi DSS-3T was observed. The sulphonate moiety was recovered in the medium largely as sulphite, and the appropriate amount of the ammonium ion was also observed. Genes [suyAB (3-sulpholactate sulpho-lyase)] encoding the known desulphonation reaction in cysteate degradation were absent from the genome, but a homologue of a putative sulphate exporter gene (suyZ) was found, and its neighbour, annotated as a D-cysteine desulphhydrase, was postulated to encode pyridoxal 5′-phosphate-coupled L-cysteate sulpho-lyase (CuyA), a novel enzyme. Inducible CuyA was detected in cysteate-grown cells. The enzyme released equimolar pyruvate, sulphite and the ammonium ion from L-cysteate and was purified to homogeneity by anion-exchange, hydrophobic-interaction and gel-filtration chromatography. The N-terminal amino acid sequence of this 39-kDa subunit confirmed the identification of the cuyA gene. The native enzyme was soluble and homomultimeric. The Km-value for L-cysteate was high (11.7 mM) and the enzyme also catalysed the D-cysteine desulphhydrase reaction. The gene cuyZ, encoding the putative sulphite exporter, was co-transcribed with cuyA. Sulphite was exported despite the presence of a ferricyanide-coupled sulphite dehydrogenase. CuyA was found in many bacteria that utilize cysteate.
22
Abbadini, M., GJ Zhu, A. Maggi, J. Pangrazzi, MB Donati, and L. Mussoni. "Dermatan sulphate induces plasminogen activator release in the perfused rat hindquarters." Blood 70, no. 6 (1987): 1858–60. http://dx.doi.org/10.1182/blood.v70.6.1858.1858.
Full textAbstract:
Abstract Heparin or heparin-like substances have been described to induce the release of plasminogen activator (PA) activity in different animal perfusion models. In this paper we report that Dermatan Sulphate (DS) is able to induce PA activity release in the perfused rat hindquarters. Perfusion of different doses of DS (0.1 to 0.8 mg/mL) stimulates a release of PA activity that is maximum after the initial two minutes of perfusion. The amount of PA activity released rises progressively within a certain concentration range of DS (0.1 to 0.4 mg/mL) and declines thereafter (0.6 to 0.8 mg/mL). The type of PA activity increased during DS perfusion was characterized by SDS-PAGE and fibrin autography as tissue-type PA (t-PA) on the basis of its mol wt (67,000 d) and inhibition by a specific anti t-PA antiserum. This effect might be considered as potentially contributing to the antithrombotic activity of DS, at least at the local level.
23
Abbadini, M., GJ Zhu, A. Maggi, J. Pangrazzi, MB Donati, and L. Mussoni. "Dermatan sulphate induces plasminogen activator release in the perfused rat hindquarters." Blood 70, no. 6 (1987): 1858–60. http://dx.doi.org/10.1182/blood.v70.6.1858.bloodjournal7061858.
Full textAbstract:
Heparin or heparin-like substances have been described to induce the release of plasminogen activator (PA) activity in different animal perfusion models. In this paper we report that Dermatan Sulphate (DS) is able to induce PA activity release in the perfused rat hindquarters. Perfusion of different doses of DS (0.1 to 0.8 mg/mL) stimulates a release of PA activity that is maximum after the initial two minutes of perfusion. The amount of PA activity released rises progressively within a certain concentration range of DS (0.1 to 0.4 mg/mL) and declines thereafter (0.6 to 0.8 mg/mL). The type of PA activity increased during DS perfusion was characterized by SDS-PAGE and fibrin autography as tissue-type PA (t-PA) on the basis of its mol wt (67,000 d) and inhibition by a specific anti t-PA antiserum. This effect might be considered as potentially contributing to the antithrombotic activity of DS, at least at the local level.
24
Pujiindiyati, E. Ristin, Wandowo Wandowo, and Zainal Abidin. "INTERPRETATION OF OXYGEN –18 ISOTOPE IN SULPHATE FROM DEEP GROUNDWATER IN JAKARTA AREA." Indonesian Journal of Chemistry 7, no. 1 (2010): 32–37. http://dx.doi.org/10.22146/ijc.21709.
Full textAbstract:
It has been done a determination of d 18O (SO42-) and d 18O (H2O) value from Jakarta deep groundwater with depth 40-140 m. The aim of this research is to know some procesess influencing the composition of oxygen isotope in groundwater sulphate. A method commonly used to determine d 18O (H2O) value is according to Epstein-Mayeda. CO2 gas resulted from equilibration process between water sample and CO2 gas standard in which oxygen isotopic reaction has occurred, is injected to mass spectrometer. For determination of d 18O (SO42-) value, Rafter method is used. CO2 gas released from reducing sulphate of water sample with graphite is injected to mass spectrometer. The results of d 18O (H2O) values obtained in this experiment have a narrow range from -5,04 0/00 to -6,65 0/00 SMOW whereas their d18O (SO42-) values have a wider range from +8,3 0/00 to +17,4 0/00 SMOW. The more constant values of d 18O (H2O) performed that evaporation effects might not occur. Based on the similarity between d18O (SO42-) values of deep groundwater and that of marine evaporite sulphate rocks, it is supposed that sulphate of Jakarta deep groundwater was derived from dissolution of this rocks. There was an indication of seawater intrusion around Pejagalan and Kamal Muara Penjaringan area based on the similarity between their d18O (SO42-) values and d18O (SO42-) of modern seawater. The contribution of oxygen from water in sulphide oxidation reaction ranged 0% to 12% suggesting that oxygen in deep groundwater sulphate was mainly derived from atmospheric molecular oxygen Keywords: oxygen isotope, sulphate, groundwater
25
Ali, Md Haider, Mohiuddin Ahmed Bhuiyan, Md Selim Reza, and Samira Karim. "Formulation and In vitro Evaluation of Oral Floating Tablets of Salbutamol Sulphate: Comparison with Effervescent Tablets." Dhaka University Journal of Pharmaceutical Sciences 15, no. 2 (2017): 203–8. http://dx.doi.org/10.3329/dujps.v15i2.30938.
Full textAbstract:
The aim of this research was to develop and evaluate gastric floating tablets of salbutamol sulphate. The oral delivery of anti-asthmatic salbutamol sulphate tablets were facilitated by preparing floating dosage form which could increase its absorption in the stomach by increasing the gastric residence time of the drug. Floating tablets were formulated by using different polymers like carbopol, xanthan gum, HPMC-K4 MCR and HPMC- K100 MCR with different proportions. A comparative study of normal effervescent tablets of salbutamol sulphate had also been done. The prepared tablets were evaluated for all their physicochemical properties and in vitro buoyancy study. In vitro dissolution studies of the formulations were done in pH 6.8 phosphate buffer using USP apparatus 2 (paddle method) at 50 rpm. Percent drug release of the formulations (F-1 to F-11) was from 87.34%- 99.12% after 12 hours. From the results, F-11 was selected as an optimized formulation based on 12 h drug release which showed minimal floating lag time and maximum floating time. On the other hand, 100% drug was released within 2 hours from the F-12 of effervescent salbutamol sulphate tablets in which polymer was absent while gas generating sodium bicarbonate and citric acid were present. The results of the study were consistent and may encourage formulating similar dosage form with other drugs.Dhaka Univ. J. Pharm. Sci. 15(2): 203-208, 2016 (December)
26
BLOM, M. Anna, Maria THUVESON та Erik FRIES. "Intracellular coupling of bikunin and the heavy chain of rat pre-α-inhibitor in COS-1 cells". Biochemical Journal 328, № 1 (1997): 185–91. http://dx.doi.org/10.1042/bj3280185.
Full textAbstract:
Pre-α-inhibitor is a serum protein consisting of two polypeptides: bikunin of 16 kDa, which carries an 8 kDa chondroitin sulphate chain, and heavy chain 3 (H3) of 74 kDa. The two polypeptides are linked through an ester bond between an internal N-acetylgalactosamine residue of the chondroitin sulphate chain and the C-terminal aspartic acid residue of H3. Both bikunin and H3 are synthesized by hepatocytes and become linked as they pass through the Golgi complex. H3 is synthesized with both N- and C-terminal extensions which are released during intracellular transport. To be able to analyse the assembly of pre-α-inhibitor in detail, we have cloned and sequenced the cDNA of rat H3. Upon expression of the protein in COS-1 cells, both propeptides were found to be released. Furthermore, co-expression of H3 and bikunin resulted in the two polypeptides becoming coupled, indicating that cells other than hepatocytes may have the capacity to form chondroitin sulphate-containing links.
27
Zhu, Zhiping, Chenlin Dai, Sen Liu, and Ye Tian. "Oxidative decomposition properties of cationic exchange resins producing SO42− in power plants." Water Science and Technology 71, no. 10 (2015): 1478–84. http://dx.doi.org/10.2166/wst.2015.109.
Full textAbstract:
The sulphate content of a system increases when strong-acid cationic exchange resins leak into a system or when sulphonic acid groups on the resin organic chain detach. To solve this problem, a dynamic cycle method was used in dissolution experiments of several resins under H2O2 or residual chlorine conditions. Results show that after performing dynamic cycle experiments for 120 hours under oxidizing environments, the SO42− and total organic carbon (TOC) released by four kinds of resins increased with time, contrary to their release velocity. The quantity of released SO42− increased as the oxidizing ability of oxidants was enhanced. Results showed that the quantity and velocity of released SO42− under residual chlorine condition were larger than those under H2O2 condition. Data analysis of SO42− and TOC released from the four kinds of resins by the dynamic cycle experiment revealed that the strength of oxidation resistance of the four resins were as follows: 650C > 1500H > S200 > SP112H.
28
Prechtel, A., M. Armbruster, and E. Matzner. "Modelling sulphate stream concentrations in the Black Forest catchments Schluchsee and Villingen." Hydrology and Earth System Sciences 7, no. 4 (2003): 552–60. http://dx.doi.org/10.5194/hess-7-552-2003.
Full textAbstract:
Abstract. The sulphate (SO4) released by mineralisation and desorption from soil can play an important role in determining concentrations of SO4 in streams. The MAGIC model was calibrated for two catchments in the Black Forest, Germany (Schluchsee and Villingen) and SO4 concentrations in the streams for the years 2016 and 2030 were predicted. Special emphasis was placed on the dynamics of soil sulphur (S) pools. At Schluchsee, 90% of soil S is stored in the organic S (Sorg) pool, whereas at Villingen, 54% is in the inorganic (Sinorg) pool. The Villingen stream chemistry was modelled successfully by measured Langmuir isotherm parameters (LIPs) for Sinorg. Schluchsee data could not be modelled satisfactorily using measured or freely adapted LIPs only, as the Sinorg pool would have to be more than five times larger than what was measured. With 60.5 mmolc SO4 m-2 yr-1 as internal soil source by mineralisation and the measured LIPs, stream data was modelled successfully. The modelling shows that in these two catchments pre-industrial concentrations of SO4 in runoff can be reached in the next two decades if S deposition decreases as intended under currently agreed national and international legislation. Sorg is the most likely dominant source of SO4 released at Schluchsee. Mineralization from the Sorg pool must be included when modelling SO4 concentrations in the stream. As the dynamics and the controlling factors of S release by mineralisation are not yet clear, this process remains a source of uncertainty for predictions of SO4 concentrations in streams. Future research should concentrate on dynamics of S mineralisation in the field, such that mathematical descriptions of long-term S-mineralisation can be incorporated into biogeochemical models. Keywords: sulphate release, organic S, mineralisation, acidification, recovery, modelling, MAGIC, catchments, predictions, Germany, forest
29
Turnbull, J. E., and J. T. Gallagher. "Sequence analysis of heparan sulphate indicates defined location of N-sulphated glucosamine and iduronate 2-sulphate residues proximal to the protein-linkage region." Biochemical Journal 277, no. 2 (1991): 297–303. http://dx.doi.org/10.1042/bj2770297.
Full textAbstract:
A strategy that we originally used to identify an N-acetylated domain adjacent to the protein-linkage sequence of heparan sulphate proteoglycan (HSPG) [Lyon, Steward, Hampson & Gallagher (1987) Biochem. J. 242, 493-498] has been adapted for analysis of the location of GlcNSO3-HexA and GlcNSO3(+/- 6S)-IdoA(2S) units most proximal to the core protein. [3H]Glucosamine-labelled HSPG from human skin fibroblasts was depolymerized by using HNO2 or heparinase under conditions that allowed cleavage of all susceptible linkages. The degraded PG was coupled to Sepharose beads through the protein component, enabling specific recovery of protein-linked resistant oligosaccharides. These were released by treatment with alkaline borohydride and analysed by gel filtration and gradient PAGE. This strategy allowed investigation of the sequence of sugar residues along the chain relative to a common reference point (i.e. the reducing end of the chain). HNO2 scission confirmed the presence of a well-defined N-acetylated sequence predominantly 9-12 disaccharide units in length proximal to the core protein. Heparinase scission produced two classes of oligosaccharides (Mr approx. 7000 and 15,000) with the general formula: IdoA(2S)-GlcNSO3-[HexA-GlcNR]n-HexA-GlcNSO3-[Hex A-GlcNAc]9 12-GlcA-Gal-Gal-Xyl in which the average value for n is 1-2 for the 7000-Mr species and approx. 22 for the 15,000-Mr species. The latter oligosaccharides extend to about one-third of the total length of the HS chains (Mr approx. 45,000). HNO2 scission of these oligosaccharides enabled hypothetical models for their sequence to be proposed. The general arrangement of N-sulphated and N-acetylated disaccharides between the proximal GlcNSO3 and terminal IdoA(2S) residues of the 15,000-Mr fragment was similar to that in the original polysaccharide, suggesting the possibility of a tandemly repeating pattern in the sequence of HS.
30
Kimura, A., T. Kawaguchi, T. Ono, et al. "Cell surface heparan sulphate and adhesive property of sublines of rat ascites hepatoma AH7974." Journal of Cell Science 90, no. 4 (1988): 683–89. http://dx.doi.org/10.1242/jcs.90.4.683.
Full textAbstract:
Two variants (74AD and 74FL) established from rat ascites hepatoma AH7974 were examined for the production of glycosaminoglycans in culture. There was no difference between the adhesive (74AD) and the floating (74FL) variants in quantity of glycosaminoglycans produced by their cultivation in minimum essential medium supplemented with 10% foetal calf serum. However, they were distinctly different in the distribution patterns of heparan sulphate. In 74FL, about 70% of total heparan sulphate was found in the culture medium in soluble form, whereas in 74AD, only 7% was found in the medium and the rest was in the cell-substratum complex. In a serum-free medium, 74AD cells grew without adhering to the substratum. After cultivation, more than 90% of total heparan sulphate was found in the cell-associated fractions and the rest in the substratum fractions. No heparan sulphate was detected in the culture medium. On the other hand, 74FL cells released heparan sulphate to the serum-free medium as much as to the serum-containing medium. The increase in amount of heparan sulphate in the culture medium of 74FL cells was supposed to be caused by failure of the cells to deposit heparan sulphate at the cell surface and not caused by increased production. Cell-substratum adhesion mechanisms involving cell surface heparan sulphate (heparan sulphate proteoglycan) and some serum intermediate(s) are discussed for 74AD cells.
31
Walsh, R. L., T. J. Dillon, R. Scicchitano, and G. McLennan. "Heparin and heparan sulphate are inhibitors of human leucocyte elastase." Clinical Science 81, no. 3 (1991): 341–46. http://dx.doi.org/10.1042/cs0810341.
Full textAbstract:
1. Heparin and heparan sulphate strongly inhibited human leucocyte elastase activity in an automated assay using the soluble substrate, n-succinyl-(l-alanine)3-p-nitroanilide (50% inhibition of 250 μl of 10 μg of human leucocyte elastase/ml was obtained with 80 μl of 2.8 μg of heparin/ml and 8 μg of heparan sulphate/ml). Less significant inhibition at the same concentrations was seen with the other glycosaminoglycans tested: hyaluronic acid and chondroitin sulphates A–C. 2. Heparin and heparan sulphate also strongly inhibited human leucocyte elastase activity towards insoluble human lung elastin, as determined by an e.l.i.s.a. for soluble elastin-derived peptides released by elastolytic activity on the elastin. This inhibition was shown not to be due to a direct interference of the glycosaminoglycans in the e.l.i.s.a. nor to the inhibition causing a change in the size of the elastin-derived peptides. However, unlike the chromogenic assay with n-succinyl-(l-alanine)3-p-nitroanilide as substrate, where heparin was the more effective inhibitor, in this assay system heparan sulphate was the more effective inhibitor (50% inhibition of 100 μl of 50 ng of human leucocyte elastase/ml was obtained with 100 μl of 4.5 μg of heparin/ml and 0.8 μg of heparan sulphate/ml). These results suggest that heparin and heparan sulphate, as components of cellular and basement membranes, are likely to have a role in protecting structural proteins, such as elastin, from the proteolytic activity of human leucocyte elastase. 3. The degree of inhibition by heparin was independent of pH within the range of pH studied (pH 6–9) and was almost immediate in the automated chromogenic assay system where a 10 s preincubation step was used. The inhibitory effect of heparin could be prevented by the addition of protamine sulphate or by the removal of heparin by an ion-exchange resin. 4. Low Mr preparations of heparin were also found to inhibit human leucocyte elastase, although preparations with Mr of 2000 or less did not inhibit the enzyme to the same extent as commercial preparations. 5. Heparin at the same concentrations did not inhibit other leucocyte enzymes, such as cathepsin G and myeloperoxidase, nor the pancreatic enzymes, pancreatic elastase, trypsin and chymotrypsin.
32
Shaklee, P. N., and H. E. Conrad. "The disaccharides formed by deaminative cleavage of N-deacetylated glycosaminoglycans." Biochemical Journal 235, no. 1 (1986): 225–36. http://dx.doi.org/10.1042/bj2350225.
Full textAbstract:
Chondroitin 4-sulphate, chondroitin 6-sulphate, dermatan sulphate and keratan sulphate were N-deacetylated by treatment with hydrazine and then cleaved with HNO2 at pH 4.0, and the resulting products were reduced with NaB3H4. This reaction sequence cleaved the glycosaminoglycans at their N-acetyl-D-glucosamine or N-acetyl-D-galactosamine residues, which were converted into 3H-labelled 2,5-anhydro-D-mannitol (AManR) or 2,5-anhydro-D-talitol (ATalR) residues respectively. The end-labelled disaccharides, composed of D-glucuronic acid (GlcA), L-iduronic acid (IdoA) or D-galactose (Gal) and one of the anhydrohexitols, were identified as follows: both chondroitin 4-sulphate and chondroitin 6-sulphate gave GlcA→ATalR(4-SO4), GlcA→ATalR(6-SO4), IdoA→ATalR (4-SO4) and GlcA(2-SO4)→ATalR(6-SO4); dermatan sulphate gave IdoA→ATalR(4-SO4), GlcA→ATalR(4-SO4), GlcA→ATalR(6-SO4)→IdoA(2-SO4)ATalR(4-SO4) and IdoA→ATalR (4,6-diSO4); keratan sulphate gave Gal(6-SO4)→AManR(6-SO4), Gal→AManR(6-SO4), Gal(6-SO4)→AManR and Gal→AManR. Several additional disaccharides were generated by treatment of the uronic acid-containing disaccharides with hydrazine to epimerize their uronic acid residues at C-5. A number of these disaccharides were found to be substrates for lysosomal sulphatases and glycuronidases. Methods were developed for the separation of all of the disaccharide products by h.p.l.c. The rate of N-deacetylation of chondroitin 4-sulphate by hydrazinolysis was significantly lower than the rate of N-deacetylation of chondroitin 6-sulphate or chondroitin. Dermatan sulphate was N-deacetylated at an intermediate rate. The relative amounts of disaccharides obtained from chondroitin 4-sulphate, chondroitin 6-sulphate and dermatan sulphate under optimum hydrazinolysis/deamination conditions were comparable with the amounts of the corresponding products released from the polymers by chondroitinase treatment.
33
ÅSTRÖM, M., and B. SPIRO. "Sources of acidity and metals in a stream draining acid sulphate soil, till and peat, western Finland, revealed by a hydrochemical and sulphur isotope study." Agricultural and Food Science 14, no. 1 (2008): 34. http://dx.doi.org/10.2137/1459606054224084.
Full textAbstract:
The main aim of this study was to determine, during extreme hydrological conditions, the source(s) of acids, sulphate and metals (alkali and alkaline earths) in the Munsala stream (western Finland) draining mainly acid sulphate soil, peat and till. Samples were collected at 6 sites along the main stem on 3 high-flow and 3 low-flow events, and were analysed for the required chemical and isotopic variables. The acid sulphate soils (located under farmland) had a large impact on the stream as indicated by pH values occasionally down to 4.0, moderately to strongly increased concentrations of inorganic solutes, and a high acid SO4 2- load characterised by negative d34S(sulphate) values. In addition, the forested areas underlain mainly with till and peat released low SO4 2- but low pH waters (down to at least 4.6) during high flows, indicating the importance of humic acids in controlling the pH. These humic acids flocculated abundantly in the middle/ lower reaches as a result of interaction with acid sulphate water. Therefore, not only the farmland acid sulphate soils but also the organic-rich soils/horizons in the forested areas contribute to water-quality deterioration.;
34
Turan, A., D. Memis, B. Karamanlioglu, N. Sut, and Z. Pamukcu. "The Prevention of Pain from Injection of Rocuronium by Magnesium Sulphate, Lignocaine, Sodium Bicarbonate and Alfentanil." Anaesthesia and Intensive Care 31, no. 3 (2003): 277–81. http://dx.doi.org/10.1177/0310057x0303100306.
Full textAbstract:
We compared the efficacy of magnesium sulphate, lignocaine, sodium bicarbonate or alfentanil in minimizing pain due to injection of rocuronium in 250 patients. After tourniquet application on the forearm, the patients were given saline, magnesium sulphate, lignocaine, sodium bicarbonate 8.4% or alfentanil, diluted into a 3 ml solution. The occlusion was released after 20 seconds, and rocuronium was injected over 10 to 15 seconds. The patients were observed and asked immediately if they had pain in the arm and the response was assessed. Reactions such as discomfort and pain, withdrawal of the hand and screaming after the administering of the rocuronium were recorded as side-effects and patients were reassessed at 24 hours postoperatively. We concluded that magnesium sulphate, lignocaine, sodium bicarbonate or alfentanil decreased the level of rocuronium injection pain. Of these drugs, magnesium sulphate, lignocaine and sodium bicarbonate were the most effective while alfentanil was the least effective.
35
Takahashi, N., H. Ishihara, S. Tejima, et al. "The core molecule from type H proteoglycan. Release of mannose-containing oligosaccharides by digestion with N-oligosaccharide glycopeptidase." Biochemical Journal 229, no. 3 (1985): 561–71. http://dx.doi.org/10.1042/bj2290561.
Full textAbstract:
Chick-embryo cartilage contains a unique set of proteoglycans. Type H proteoglycan (PG-H) is the most abundant, constituting over 90% of the total cartilage hexuronate. We previously showed that treatment of PG-H with chondroitinase ACII and keratanase yields a protein-enriched core molecule [PG(-CS, KS)] with enzymically modified linkage oligosaccharides of the chondroitin sulphate and keratan sulphate chains. We report here that further treatment of PG(-CS, KS) with pepsin and N-oligosaccharide glycopeptidase (almond glycopeptidase) released four distinct types of mannose-containing oligosaccharide. Two of them were shown to be: (Formula: see text). Of the mannose-containing glycopeptides formed by pepsin digestion, about 40% (as mannose) were resistant to N-oligosaccharide glycopeptidase. Since the resistant fraction was enriched in keratan sulphate remnants, it is suggest that the mannose-containing oligosaccharides in this fraction represent those located in a keratan sulphate-enriched region of PG-H.
36
SCUDDER, Peter, Ping W. TANG, Elizabeth F. HOUNSELL, Huseyin MEHMET, Ten FEIZI, and Alexander M. LAWSON. "Isolation and characterization of sulphated oligosaccharides released from bovine corneal keratan sulphate by the action of endo-beta-galactosidase." European Journal of Biochemistry 157, no. 2 (1986): 365–73. http://dx.doi.org/10.1111/j.1432-1033.1986.tb09678.x.
Full text
37
Cwalina, Beata, Weronika Dec, Wojciech Simka, Joanna Michalska, and Marzena Jaworska-Kik. "Biofilm Formation on NiTi Surface by Different Strains of Sulphate Reducing Bacteria (Desulfovibrio desulfuricans)." Solid State Phenomena 227 (January 2015): 302–5. http://dx.doi.org/10.4028/www.scientific.net/ssp.227.302.
Full textAbstract:
Bacteria of Desulfovibrio genus belong to group of widespread sulphate-reducing bacteria (SRB). D. desulfuricans is considered one among many bacterial species involved in microbiologically influenced corrosion (MIC) of metals, mainly of stainless steels and other alloys. SRB can produce gaseous hydrogen sulphide. This gas is released into the environment leading to formation of metal sulphides that significantly influence electrochemical processes and ultimately enhance the corrosion of materials. Biofilms formed by these bacteria are especially harmful for highly alloyed steels and many alloys. The aim of this work was to compare the character of growth and biofilm formation by three strains of D. desulfuricans (standard soil strain DSM and two wild intestinal strains: DV/A and DV/B) on the surface of NiTi alloy.
38
Shibata, Michio, Takanari Tsuda, Hiroshi Itagaki та ін. "Interleukin-1α and Interleukin-8 Release by Human Keratinocyte Cell Culture Treated with Surfactants". Alternatives to Laboratory Animals 25, № 2 (1997): 161–71. http://dx.doi.org/10.1177/026119299702500209.
Full textAbstract:
The effects of four cosmetic surfactants on interleukin (IL)-1α and IL-8 release from human keratinocytes were studied to investigate the feasibility of using these effects for the prediction of the irritation potential of chemicals. After exposure of cells to surfactants, the amounts of IL-1α and IL-8 released into culture medium were measured by ELISA. Cytotoxicity was evaluated by using the neutral red uptake (NRU) cytotoxicity assay. Cytokine release was increased 7–15 times by sodium lauryl sulphate (SLS), laurtrimonium chloride, cocamidopropyl betaine (CPB) and Oleth-5 at cytotoxic concentrations. IL-8 release was increased 3–4 times by SLS, CPB and Oleth-5 at subcytotoxic concentrations. After exposure to SLS, IL-1α was released within 1 hour, suggesting that IL-1α release is associated with membrane damage, whereas IL-8 release continued for 24 hours, suggesting that IL-8 was produced within the cells. Cytotoxicity tests and IL-8 release assays were also performed on seven other surfactants. The results show that moderate irritants CPB and PEG-4 dioleate, which have weak cytotoxic effects, significantly increased IL-8 release from human keratinocytes. It is suggested that measurement of IL-8 release is useful for predicting the irritation potential of chemicals which cannot be detected by using the NRU cytotoxicity assay.
39
Johansson, S., K. Hedman, L. Kjellén, J. Christner, A. Vaheri, and M. Höök. "Structure and interactions of proteoglycans in the extracellular matrix produced by cultured human fibroblasts." Biochemical Journal 232, no. 1 (1985): 161–68. http://dx.doi.org/10.1042/bj2320161.
Full textAbstract:
Subconfluent cultures of human embryonic skin fibroblasts were labelled with [35S]sulphate for 3 days, after which cell-free extracellular matrix was isolated. A chondroitin sulphate proteoglycan (CSPG) and a heparan sulphate proteoglycan (HSPG) were purified from the matrix. Chromatography on Sepharose CL-2B gave peak Kav. values of 0.35 and 0.38 respectively for the CSPG and the HSPG. The polysaccharide chains released from the two PGs were of similar size (Kav. 0.50 on Sepharose CL-4B). Approx. 50% of the CSPG showed affinity for hyaluronic acid (HA). However, it differed immunologically from the HA-aggregating CSPG of human articular cartilage, and had a larger core protein (apparent molecular mass 290 kDa) than had the cartilage PG. Neither metabolically [35S]sulphate-labelled PGs, isolated from the medium of fibroblast cultures, nor chemically 3H-labelled polysaccharides (HA, CS, HS and heparin) were incorporated into the extracellular matrix when added to unlabelled cell cultures. These results indicate that the matrix PGs are not derived from the PGs present in the medium and that an interation between polysaccharide chains and matrix components is not sufficient for incorporation of PGs into the matrix. Incubation of cell-free 35S-labelled matrix with unlabelled polysaccharides did not lead to the release of any 35S-labelled material, supporting this conclusion. Furthermore, so-called ‘link proteins’ were not present in the fibroblast cultures, indicating that the CSPGs were anchored in the matrix in a manner different from the link-stabilized association of CSPG with HA in chondrocyte matrix. The identification of a proteinase, secreted by fibroblasts in culture, that after activation with heparin has the ability to release 35S-labelled PGs from the matrix may also indicate that the core proteins are important for the association of the PGs to the matrix.
40
Abduh, Andin Muhammad, and Wahida Annisa. "Interaction of Paddy Varieties and Compost with Flux of Methane in Tidal Swampland." Journal of Tropical Soils 21, no. 3 (2017): 179–86. http://dx.doi.org/10.5400/jts.2016.v21i3.179-186.
Full textAbstract:
Varieties and organic materials have a very important role to the flux of methane (CH4) on paddy cultivation, especially on wetlands. Purpose of this research to determine the amount of methane emissions that released from paddy cultivation in acid sulphate soils with the use of different varieties and paddy straw composting. Acid sulfate soil samples taken Experimental Farm Swampland Agricultural Research Center (BALITTRA), Tanjung Harapan, District Alalak, Barito Kuala, South Kalimantan. This research uses Randomized Complete Design of two factors. The first factor is the use of paddy varieties and the second factor is the use of paddy straw compost. Research shows that there is a very real interaction between the two factors. Treatment varieties Inpara 3 + without paddy straw compost releases CH4 flux most low at 0,030 mg.m-2.day-1, while treatment Inpari 30 + paddy straw compost 5 Mg. ha-1 release most CH4 flux is 0.571 mg. m-2.day-1.
41
Abduh, Andin Muhammad, and Wahida Annisa. "Interaction of Paddy Varieties and Compost with Flux of Methane in Tidal Swampland." JURNAL TANAH TROPIKA (JOURNAL OF TROPICAL SOILS) 21, no. 3 (2017): 179. http://dx.doi.org/10.5400/jts.v21i3.2206.
Full textAbstract:
Varieties and organic materials have a very important role to the flux of methane (CH4) on paddy cultivation, especially on wetlands. Purpose of this research to determine the amount of methane emissions that released from paddy cultivation in acid sulphate soils with the use of different varieties and paddy straw composting. Acid sulfate soil samples taken Experimental Farm Swampland Agricultural Research Center (BALITTRA), Tanjung Harapan, District Alalak, Barito Kuala, South Kalimantan. This research uses Randomized Complete Design of two factors. The first factor is the use of paddy varieties and the second factor is the use of paddy straw compost. Research shows that there is a very real interaction between the two factors. Treatment varieties Inpara 3 + without paddy straw compost releases CH4 flux most low at 0,030 mg.m-2.day-1, while treatment Inpari 30 + paddy straw compost 5 Mg. ha-1 release most CH4 flux is 0.571 mg. m-2.day-1.
42
Nanda, Shivani, Nikhil Sood, B. V. K. Reddy, and Tanmay S. Markandeywar. "Preparation and Characterization of Poly(vinyl alcohol)-chondroitin Sulphate Hydrogel as Scaffolds for Articular Cartilage Regeneration." Indian Journal of Materials Science 2013 (November 17, 2013): 1–8. http://dx.doi.org/10.1155/2013/516021.
Full textAbstract:
The aim of the study was to develop PVA-CS hydrogel scaffolds using glutaraldehyde as a cross-linking agent by chemical cross-linking method in order to obtain biomimetic scaffolds for articular cartilage regeneration. The introduction of PVA enhances the mechanical and bioadhesive properties to the native tissue while chondroitin sulphate enhances the glycosaminoglycan content of extracellular matrix. The role of hydrogel as cartilage regeneration scaffold was evaluated by swelling study, porosity, rheological behaviour, in vitro degradation, and quantification of released chondroitin sulphate. In vivo results showed that cross-linked hydrogels repaired defects with no sign of inflammation as it was well anchored to tissue in the formation of new articular surface. It may be concluded that the addition of chondroitin sulphate to the PVA polymer develops a novel composite with significant applications in cartilage tissue engineering.
43
Davies Jones, E., F. A. Hashim, Y. Kajita, et al. "Interaction of autoantibodies to thyrotropin receptor with a hydrophilic subunit of the thyrotropin receptor." Biochemical Journal 228, no. 1 (1985): 111–17. http://dx.doi.org/10.1042/bj2280111.
Full textAbstract:
Reduction of human thyroid membranes with dithiothreitol caused the release of a water-soluble glycoprotein which neutralized the thyrotropin (TSH) receptor-binding and thyroid-stimulating activities of Graves‘ serum. Analysis of the protein by gel filtration and sucrose density gradient centrifugation allowed estimates of 3.45 nm for the Stokes’ radius, 3.6 S for the s20,w and 47 000 +/- 5000 (mean +/- S.D.; n = 4) for the Mr. The material released by dithiothreitol treatment could be crosslinked to 125I-labelled TSH coupled to N-hydroxysuccinimidyl 4-azidobenzoate (125I-HSAB-TSH), suggesting that it contained a component of the TSH receptor. Furthermore, analysis of the crosslinked material by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis indicated that it contained the TSH receptor A subunit (Mr 50 000). Several factors suggested therefore that the glycoprotein released by dithiothreitol treatment of human thyroid membranes was the TSH receptor A subunit. In particular, (a) both preparations were hydrophilic and were released from membranes by reduction, (b) they had similar Mr values and (c) both preparations crosslinked to 125I-HSAB-TSH. Material similar to the TSH receptor A subunit was released from thyroid membranes by treatment with papain, probably as a result of cleavage of the receptor A subunit at a site close to the interchain disulphide bridge. A similar mechanism, involving thyroid proteinases, was probably involved in release of material with similar properties to the TSH receptor A subunit during freezing and thawing of human thyroid homogenates.
44
SMELAND, Sigbjørn, Svein Olav KOLSET, Malcolm LYON, Kaare R. NORUM, and Rune BLOMHOFF. "Binding of perlecan to transthyretin qin vitro." Biochemical Journal 326, no. 3 (1997): 829–36. http://dx.doi.org/10.1042/bj3260829.
Full textAbstract:
Transthyretin is one of two specific proteins involved in the transport of thyroid hormones in plasma; it possesses two binding sites for serum retinol-binding protein. In the present study we demonstrate that transthyretin also interacts in vitro with [35S]sulphate-labelled material from the medium of HepG2 cells. By using the same strategy as for purifying serum retinol-binding protein, [35S]sulphate-labelled medium was specifically eluted from a transthyretin-affinity column. Ion-exchange chromatography showed that the material was highly polyanionic, and its size and alkali susceptibility suggested that it was a proteoglycan. Structural analyses with chondroitinase ABC lyase and nitrous acid revealed that approx. 20% was chondroitin sulphate and 80% heparan sulphate. Immunoprecipitation showed that the [35S]sulphate-labelled material contained perlecan. Further analysis by binding studies revealed specific and saturable binding of 125I-transthyretin to perlecan-enriched Matrigel. Because inhibition of sulphation by treating HepG2 cells with sodium chlorate increased the affinity of the perlecan for transthyretin, and [3H]heparin was not retained by the transthyretin affinity column, the binding is probably mediated by the core protein and is not a protein–glycosaminoglycan interaction. Because perlecan is released from transthyretin in water, the binding might be due to hydrophobic interactions.
45
Hopwood, J. J., and H. Elliott. "Urinary excretion of sulphated N-acetylhexosamines in patients with various mucopolysaccharidoses." Biochemical Journal 229, no. 3 (1985): 579–86. http://dx.doi.org/10.1042/bj2290579.
Full textAbstract:
Sulphated N-acetylhexosamines have been isolated from human urine and tentatively identified as N-acetylglucosamine 6-sulphate (GlcNAc6S), N-acetylgalactosamine 6-sulphate (GalNAc6S), N-acetylgalactosamine 4-sulphate (GalNAc4S) and N-acetylgalactosamine 4,6-disulphate (GalNAc4,6diS). Urine from mucopolysaccharidosis-Type-IIID, -IVA and -VI patients compared with that from normal individuals contains elevated levels of GlcNAc6S (380-fold), GalNAc6S (180-fold) and GalNAc4S (420-fold) respectively. Urine from mucopolysaccharidosis-Type-VI patients also contain more than 600 times the normal level of GalNAc4,6diS. Urine from a mucolipidosis-Type-II and a multiple-sulphatase-deficient patient, and, in general, all mucopolysaccharidosis patients studied, contain at least 5-10-fold elevations of sulphated N-acetylhexosamines over the levels detected in urine from normal controls and a alpha-mannosidosis patient. Urine from patients with clinically mild phenotypes contains less sulphated N-acetylhexosamines than isolated from urine of clinically severe mucopolysaccharidosis patients. The source of the four sulphated N-acetylhexosamines is not known. However, incubation of a series of oligosaccharide substrates, derived from keratan sulphate and chondroitin 6-sulphate and containing non-reducing-end beta-linked 6-sulphated N-acetylhexosamine residues, with homogenates of cultured human skin fibroblasts has indirectly been shown to release GlcNA6S and GalNAc6S respectively. Release of GalNAc4S could not be demonstrated in similar incubations of oligosaccharide substrates derived from chondroitin 4-sulphate and containing non-reducing-end beta-linked GalNAc4S residues. We propose that some, if not all, of the sulphated N-acetylhexosamine present in human urine is derived from the action of beta-N-acetylhexosaminidase on sulphated GlcNAc or GalNAc residues at the non-reducing end of keratan sulphate, dermatan sulphate or chondroitin sulphate.
46
Szurkowska, Katarzyna, Paulina Kazimierczak, and Joanna Kolmas. "Mg,Si—Co-Substituted Hydroxyapatite/Alginate Composite Beads Loaded with Raloxifene for Potential Use in Bone Tissue Regeneration." International Journal of Molecular Sciences 22, no. 6 (2021): 2933. http://dx.doi.org/10.3390/ijms22062933.
Full textAbstract:
Osteoporosis is a worldwide chronic disease characterized by increasing bone fragility and fracture likelihood. In the treatment of bone defects, materials based on calcium phosphates (CaPs) are used due to their high resemblance to bone mineral, their non-toxicity, and their affinity to ionic modifications and increasing osteogenic properties. Moreover, CaPs, especially hydroxyapatite (HA), can be successfully used as a vehicle for local drug delivery. Therefore, the aim of this work was to fabricate hydroxyapatite-based composite beads for potential use as local carriers for raloxifene. HA powder, modified with magnesium and silicon ions (Mg,Si-HA) (both of which play beneficial roles in bone formation), was used to prepare composite beads. As an organic matrix, sodium alginate with chondroitin sulphate and/or keratin was applied. Cross-linking of beads containing raloxifene hydrochloride (RAL) was carried out with Mg ions in order to additionally increase the concentration of this element on the material surface. The morphology and porosity of three different types of beads obtained in this work were characterized by scanning electron microscopy (SEM) and mercury intrusion porosimetry, respectively. The Mg and Si released from the Mg,Si-HA powder and from the beads were measured by inductively coupled plasma optical emission spectrometry (ICP-OES). In vitro RAL release profiles were investigated for 12 weeks and studied using UV/Vis spectroscopy. The beads were also subjected to in vitro biological tests on osteoblast and osteosarcoma cell lines. All the obtained beads revealed a spherical shape with a rough, porous surface. The beads based on chondroitin sulphate and keratin (CS/KER-RAL) with the lowest porosity resulted in the highest resistance to crushing. Results revealed that these beads possessed the most sustained drug release and no burst release effect. Based on the results, it was possible to select the optimal bead composition, consisting of a mixture of chondroitin sulphate and keratin.
47
van den Heuvel, L. P. W. J., J. van den Born, T. J. A. M. van de Velden, et al. "Isolation and partial characterization of heparan sulphate proteoglycan from the human glomerular basement membrane." Biochemical Journal 264, no. 2 (1989): 457–65. http://dx.doi.org/10.1042/bj2640457.
Full textAbstract:
Heparan sulphate proteoglycan was solubilized from human glomerular basement membranes by guanidine extraction and purified by ion-exchange chromatography and gel filtration. The yield of proteoglycan was approx. 2 mg/g of basement membrane. The glycoconjugate had an apparent molecular mass of 200-400 kDa and consisted of about 75% protein and 25% heparan sulphate. The amino acid composition was characterized by a high content of glycine, proline, alanine and glutamic acid. Hydrolysis with trifluoromethanesulphonic acid yielded core proteins of 160 and 110 kDa (and minor bands of 90 and 60 kDa). Alkaline NaBH4 treatment of the proteoglycan released heparan sulphate chains with an average molecular mass of 18 kDa. HNO2 oxidation of these chains yielded oligosaccharides of about 5 kDa, whereas heparitinase digestion resulted in a more complete degradation. The data suggest a clustering of N-sulphate groups in the peripheral regions of the glycosaminoglycan chains. A polyclonal antiserum raised against the intact proteoglycan showed reactivity against the core protein. It stained all basement membranes in an intense linear fashion in immunohistochemical studies on frozen kidney sections from man and various mammalian species.
48
Thomas, G. J., R. M. Mason, and M. Davies. "Characterization of proteoglycans synthesized by human adult glomerular mesangial cells in culture." Biochemical Journal 277, no. 1 (1991): 81–88. http://dx.doi.org/10.1042/bj2770081.
Full textAbstract:
1. The newly synthesized proteoglycans from human adult glomerular mesangial cells labelled in vitro for 24 h with [35S]sulphate have been characterized using biochemical and immunological techniques. 2. The following proteoglycans were identified (% of total synthesized). (i) A large chondroitin sulphate proteoglycan, CSPG-I, Mr approximately 1 x 10(6) (10.6%). This proteoglycan consisted of a protein core of Mr approximately 4 x 10(5) and glycosaminoglycan chains of Mr 2.5 x 10(4), and was present in both the cell layer and the culture medium. (ii) A major small dermatan sulphate proteoglycan, DSPG-I, Mr 3.5 x 10(5) (46%), which was mainly located in the culture medium. (iii) A second minor small dermatan sulphate, DSPG-II, Mr approximately 2 x 10(5) (9.8%). This molecule was exclusively located in the culture medium. (iv) A large heparan sulphate proteoglycan, HSPG-I, Mr 8 x 10(5) (3.3%). (v) A second large heparan sulphate proteoglycan HSPG-II, Mr approximately 6 x 10(5) (23%). HSPG-I and HSPG-II were extracted from both the culture medium and the cell layer. 3. Western blot analysis of the core proteins released by chondroitin ABC lyase treatment of DSPG-I and DSPG-II identified these dermatan sulphate proteoglycans as biglycan and decorin respectively. Both DSPG-I and DSPG-II had core proteins of Mr 45,000. 4. The cell-layer-associated forms of CSPG-I, HSPG-I and HSPG-II were accessible to limited trypsin treatment, bound to octyl-Sepharose and could be inserted into liposomes, indicating a possible cell membrane location. 5. Pulse-chase experiments indicated that the cell-layer-associated [35S]proteoglycans undergo limited metabolism to inorganic [35S]sulphate, the majority of which is accounted for by the degradation of HSPG-II and to a lesser extent DSPG-I.
49
Vicente, M. A., M. Suarez, M. A. Bañares-Muñoz, and J. M. M. Pozas. "Reduction of Fe(III) in a high-iron saponite. Pillaring of the reduced samples with Al13 oligomers." Clay Minerals 33, no. 2 (1998): 213–20. http://dx.doi.org/10.1180/000985598545570.
Full textAbstract:
AbstractA high-iron content saponite, of the variety griffithite, was reduced using sodium dithionite and hydrazonium sulphate solutions. An important amount of Fe3+ was reduced during the treatments. When using sodium dithionite as reducing agent, the reduction was accompanied by the substitution of Ca2+ by Na+ as the exchangeable cation. When using hydrazonium sulphate, the reduction was accompanied by acid activation of the clay, the protons being released in the oxidation reaction of the hydrazonium cation. The charge balance in the clay layers is affected by the reduction processes. These structural changes do not significantly affect the pillaring ability of the clay, which is similar in the reduced solids and in the natural griffithite.
50
Tribovillard, Nicolas, Olivier Averbuch, Anne Bialkowski, and Jean-François Deconinck. "Early diagenesis of marine organic-matter and magnetic properties of sedimentary rocks: the role of iron limitation and organic-matter source organisms." Bulletin de la Société Géologique de France 173, no. 4 (2002): 295–306. http://dx.doi.org/10.2113/173.4.295.
Full textAbstract:
Abstract The magnetic parameters of sedimentary rocks can record accurately tectonic and climatic influences upon sedimentary processes, when they are not altered during diagenesis. This paper is focused on the possible alteration of the primary magnetic-susceptibility signal during early diagenesis of marine organic matter (OM). In the late Kimmeridgian-Tithonian Argiles de Châtillon Formation (Fm.) of the Boulonnais area (northern France – lateral time equivalent of the distal organic-rich sediments of the Kimmeridge Clay Fm. of Dorset), the organic content is dominated by amorphous OM (AOM), either brown or orange, originating from selective preservation or sulphurisation, respectively. Total sulphur content correlates well with orange + brown AOM abundance, and organic S content correlates well with orange AOM abundance. The magnetic signal of these claystones and paper shales is dominantly carried by clay minerals. The magnetic susceptibility vs. brown-AOM abundance relationship shows a clear correlation. Furthermore, if the part of the magnetic-susceptibility signal linked to the lithoclastic fraction of the sediments is removed from the total signal, a positive correlation is also drawn between the brown-AOM abundance and the ‘excess’ magnetic susceptibility. The cause for this resides in the iron-sulphide abundance. The presence of both types of AOM implies that intense sulphate reduction took place and that the HS−/H2S released reacted with either organic molecules (orange AOM dominating the palynofacies) or reactive iron (brown AOM dominating). When reactive iron was abundant enough and when sulphate reduction-induced sulphide ions could react with it, iron sulphides could form and this sediment component (present now as pyrite) influences the magnetic-susceptibility signal. The type of dominating source organisms (phytoplankton) may condition the reactivity of OM towards sulphide ions. This may influence iron-sulphide formation, and in turn the sediment magnetic signal.