共查询到20条相似文献,搜索用时 31 毫秒
1.
Andrew J. Quantock Robert D. Young Tomoya O. Akama 《Cellular and molecular life sciences : CMLS》2010,67(6):891-906
Keratan sulphate (KS) is the predominant glycosaminoglycan (GAG) in the cornea of the eye, where it exists in proteoglycan
(PG) form. KS-PGs have long been thought to play a pivotal role in the establishment and maintenance of the array of regularly-spaced
and uniformly-thin collagen fibrils which make up the corneal stroma. This characteristic arrangement of fibrils allows light
to pass through the cornea. Indeed, perturbations to the synthesis of KS-PG core proteins in genetically altered mice lead
to structural matrix alterations and corneal opacification. Similarly, mutations in enzymes responsible for the sulphation
of KS-GAG chains are causative for the inherited human disease, macular corneal dystrophy, which is manifested clinically
by progressive corneal cloudiness starting in young adulthood. 相似文献
2.
Rabbit corneal cells were cultivated for 21 days and then exposed to Na235SO4, a precursor of sulfated glycosaminoglycans (GAG). All 3 cell types of the cornea, the fibroblasts, the epithelial as well as the endothelial cells, synthesize GAG. The fractionation-patterns of the epithelial and endotherlial GAG are almost identical and differ clearly from the one of fibroblastic GAG. 相似文献
3.
Marianne E. Schwager-Hübner M. C. Gnädinger 《Cellular and molecular life sciences : CMLS》1976,32(1):15-16
Summary Rabbit corneal cells were cultivated for 21 days and then exposed to Na2
35SO4, a precursor of sulfated glycosaminoglycans (GAG). All 3 cell types of the cornea, the fibroblasts, the epithelial as well as the endothelial cells, synthesize GAG. The fractionation-patterns of the epithelial and endothelial GAG are almost identical and differ clearly from the one of fibrolastic GAG.Supported by SNSF, grant No. 3.534.71. 相似文献
4.
As part of studies on the pathogenesis of exophthalmos of Graves' disease, the biochemical composition of human retrobulbar tissue was investigated. The connective tissue was composed of 72.7% lipid, 23.8% water and 3.5% dried defatted tissue. Total tissue glycosaminoglycan (GAG) amounted to 0.18% of dried defatted tissue. Approximately 27% of the total hexosamine and 19% of the total tissue galactosamine were recovered in the GAG fraction. Cellulose microcolumn fractionation of GAG showed that the hyaluronic acid and dermatan sulfate were the two major GAG species. 相似文献
5.
Acid GAG were isolated from hepatic tissue from 3 patients with Hurler syndrome and 3 normal controls. Gross elevations in the uronic acid and hexosamine contents were found in Hurler livers compared with the normal ones. The total GAG concentration was significantly increased (about 25fold) in Hurler patients. 相似文献
6.
R. Evangelisti G. Stabellini A. Venturoli P. Carinci 《Cellular and molecular life sciences : CMLS》1982,38(5):616-618
Summary The glycosaminoglycans (GAG) secreted by primary fibroblasts cultures removed from chick embryo skin after 7 and 14 days of
incubation have been investigated. Differences in GAG composition have been detected, depending on age and on the composition
of the nutrient medium.
This study was supported in part by an Italian Ministero Publica Istruzione grant. 相似文献
7.
S. Deb S. Som S. Basu I. B. Chatterjee 《Cellular and molecular life sciences : CMLS》1981,37(9):940-941
Summary Reactive sulfhydryl groups of major hemoglobins from guinea-pig, rat and cat reduced dehydroascorbic acid to ascorbic acid leading to formation of intrachain disulfide bonds. Hybridization experiments indicated that the reduction was carried out by thea chain of cat hemoglobin.This work was supported in part by UGC and a DST grant HCS/DST/258/76. 相似文献
8.
J. A. Kofoed A. A. Tocci A. C. Barceló 《Cellular and molecular life sciences : CMLS》1978,34(5):577-578
Summary Acid GAG were isolated from hepatic tissue from 3 patients with Hurler syndrome and 3 normal controls. Gross elevations in the uronic acid and hexosamine contents were found in Hurler livers compared with the normal ones. The total GAG concentration was significantly increased (about 25fold) in Hurler patients.This work was partially supported by research grants from the Conicet, Argentina. 相似文献
9.
Detection of caprine arthritis-encephalitis- and maedi-visna viruses using the polymerase chain reaction 总被引:3,自引:0,他引:3
Summary The polymerase chain reaction (PCR) was used to demonstrate proviral DNA of lentiviruses of small ruminants in cultured cells. Primers for the Taq polymerase were selected in the GAG gene of Icelandic maedi-visna virus and POL gene of caprine arthritis-encephalitis (CAE) virus. Using PCR, proviral DNA of CAE virus was detected at 1 day post infection, 4 days beforeviral protein could be demonstrated using a sensitive immunoblotting protocol and 6 days before the appearance of syncytia. Primers derived from the published sequence of CAE virus successfully primed for the synthesis of homologous virus and Icelandic maedi-visna viruss but not for maedi-visna virus isolated in The Netherlands. In contrast, primers derived from the GAG region of Icelandic maedi-visna virus allowed the amplification of DNA of homologous virus, maedi-visna virus isolated in The Netherlands as well as CAE virus. 相似文献
10.
J Bensimon 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1977,284(19):1959-1962
In a first experiment, cells were cultured in media supplemented by nickel sulphate, irradiated in same media and cultured in same media after irradiation. In a second experiment, cells were cultured during 18 hrs. in media supplemented by nickel sulphate, and then cells were washed and cultured in normal media where they were irradiated. The nickel sulphate toxicity appears as a creasing function of the nickel sulphate concentration and the nickel sulphate action endurance. The nickel sulphate toxic effect is amplified by X-Rays. This amplification is a time function that depends on the X-Ray dose, nickel sulphate concentration and period of time from the outset of culture to the irradiation. The nickel sulphate toxic effect appears faster when nickel works after X-Rays. 相似文献
11.
The range of (presumed) polyketide constituents in comatalid crinoids has been extended to include bianthronyls, meso-naphthodianthrones and sulphate esters of various of the polyketides. Several species of fish are deterred from eating food by the inclusion in it of these sulphates at the concentration found in crinoids. Sodium 2-hydroxy-anthraquinone sulphate and anthraquinone-2-suphonate were also active as antifeedants for the species tested. 相似文献
12.
T. Dalton 《Cellular and molecular life sciences : CMLS》1976,32(11):1421-1423
Summary 5-Hydroxytryptamine creatinine sulphate loses its biological activity when maintained at room temperature. The loss of 5-HT activity (in stimulating sodium transport across frog skin) is greater than the loss of creatinine sulphate activity (inhibition of sodium transport). 相似文献
13.
T Dalton 《Experientia》1976,32(11):1421-1423
5-Hydroxytryptamine creatinine sulphate loses its biological activity when maintained at room temperature. The loss of 5-HT activity (in stimulating sodium transport across frog skin) is greater than the loss of creatinine sulphate activity (inhibition of sodium transport). 相似文献
14.
C. J. Branford White 《Cellular and molecular life sciences : CMLS》1978,34(8):1036-1037
Summary Sulphated proteoglycans were isolated using a dissociative method of extraction. Cerebrum accounted for the major portion of proteochondroitin sulphate in brain, whereas the brain stem fraction contained over half the proteoheparan sulphate. Chemical characterization studies demonstrated that heparan sulphate from cerebellum contain more N-sulphate glucosamine residues. 相似文献
15.
16.
Syndecans are a family of integral membrane proteoglycans with conserved membrane-spanning and intracellular domains but with structurally distinct extracellular domains (ectodomains). They are known to function as heparan sulphate co-receptors in fibroblast growth factor signalling as well as to link cells directly to the extracellular matrix. These and other biological activities of syndecans involve specific interactions of the heparan sulphate side chains of syndecans with cytokines and extracellular matrix proteins. Four different vertebrate syndecans, designated as syndecans 1–4 (or syndecan, fibroglycan, N-syndecan and amphiglycan, respectively), are known. During embryonic development, syndecans have specific and highly regulated expression patterns that are distinct from the expression in adult tissue, suggesting an active role in morphogenetic processes. The developmental expression of syndecans is particularly intense in mesenchymal condensates and at epithelium mesenchyme interfaces, where a number of heparan sulphate-binding cytokines and matrix components are also expressed in a regulated manner, ofter spatially and temporally co-ordinated with the syndecan expression. Recent evidence indicates that the regulation of heparan sulphate fine structure (mainly the number and arrangement of sulphate groups along the polymer) provides a mechanism for the cellular control of syndecan-protein interactions. Furthermore, morphogenetically active cytokines such as fibroblast growth factor-2 and transforming growth factor-β participate in the regulation of syndecan expression and glycosaminoglycan structure. This review discusses the developmental expression and binding functions of syndecans as well as the molecular regulation of specific heparan sulphate-protein interactions. 相似文献
17.
Summary The effect of sodium fluoride on H+ ion secretion was investigated in the isolated distended mouse stomach. It was found that sodium fluoride on its own caused dose-related stimulation of H+ ion secretion. Sodium fluoride did not inhibit H+ ion secretion induced by histamine. The possible mechanisms involved are discussed. It is considered that sodium fluoride might stimulate H+ ion secretion by causing histamine release and by increasing cyclic AMP formation in the intact gastric mucosa. 相似文献
18.
19.
J. A. Rideout Narelle B. Smith M. D. Sutherland 《Cellular and molecular life sciences : CMLS》1979,35(10):1273-1274
Summary The range of (presumed) polyketide constituents in comatalid crinoids has been extended to include bianthronyls, meso-naphthodianthrones and sulphate esters of various of the polyketides. Several species of fish are deterred from eating food by the inclusion in it of these sulphates at the concentration found in crinoids. Sodium 2-hydroxy-anthraquinone sulphate and anthraquinone-2-suphonate were also active as antifeedants for the species tested.Acknowledgments. This author is indebted to the Australian Research Grants Commission for financial support, to Miss A. Clark of the British Museum of Natural History, London, and Ms J. Marshall of the Australian Museum, Sydney, for identifications of crinoid specimens and to Mr C. Lee, Director of the Deception Bay Laboratory of the Qld. Fisheries Service for providing facilities, fish and valuable advice. 相似文献
20.
J Bensimon J N Rimbers 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1977,284(10):867-869
Human leukaemic cells of the established line REH, cultured in media supplemented by nickel suplhate have been irradiated by X-Rays. The nickel sulphage and the X-rays have toxic effects that appear as independent or interdependent effects according to the X-ray doses, the nickel sulphate concentration and the nickel sulphate action endurances. 相似文献