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  • 1
    ISSN: 1365-2133
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: SUMMARY.— The potassium salts of methyl [35S] sulphate and butyl [35S] sulphate have been prepared and their ability to migrate across selected human skin samples from aqueous, unbuffered solutions examined. By comparison to the results obtained with potassium dodecyl [35S] sulphate in the previous paper, both the present sulphate esters are able to migrate across intact whole skin samples with the methyl ester exhibiting the higher order of migration. Application of the dodecyl ester and the butyl ester in dimethyl sulphoxide solutions did not alter the pattern of migration whereas the methyl ester showed a concentration dependant accelerant relationship with increasing concentrations of dimethyl sulphoxide. Limited studies on inorganic aaSO2 ions indicated that this substance did not migrate across whole skin samples from aqueous unbuffered solutions. The primary resistance barrier t the passage of each of the above test materials was absent when “stripped” skin samples were used as the diffusion-membranes. The implications of these findings are discussed.
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  • 2
    ISSN: 1365-2133
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: SUMMARY.— The results obtained in the present communication are consistent with the view that the primary resistance zone to the percutaneous migration of potassium dodecyl [45S] sulphate from aqueous, unbuffered solutions across human skin samples resides in the horny layer. It is further proposed that a secondary resistance zone is present in the combined epidermal and dermal regions. Application of the $$S-lablelled ester in dimethyl sulphoxide in a concentration range 50 100% did not influence the rate of migration. By contrast, pretreatment of isolated horny layers by total immersion in 100% dimethyl sulphoxide for four hours at temperatures up to 60 C, markedly reduced the barrier function. Control experiment involving pretreatment in water were without effect. Pretreatment of whole skin samples in position in the diffusion cells using 100% dimethyl sulphoxide at temperatures up to 60 C, did not reduce the capacity of the barrier towards potassium dodecyl [45S] sulphate.
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 23 (1977), S. 13-17 
    ISSN: 1432-0827
    Keywords: Dental calculus ; Glycopeptide ; Chemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary A method is described for the isolation and purification of a sulphated glycopeptide from human supragingival calculus. The compound was isolated after using EDTA treatment, 2 M CaCl2 extraction, proteolytic digestion, ethanol precipitation, and finally purified by DEAE cellulose chromatography. It migrated as a single component on cellulose acetate electrophoresis, and chemical and infrared spectral analysis showed the presence of covalently attached sulphate groups. The sulphated glycopeptide was distinguished from being a sulphated glycosaminoglycan.
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 22 (1977), S. 227-229 
    ISSN: 1432-0827
    Keywords: Glycosaminoglycan ; Hyaluronic acid ; Dental calculus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Abstract A method is described for the isolation of heteropolysaccharides from human supragingival calculus. One component was identified as hyaluronic acid, by electrophoretic mobility, testicular hyaluronidase digestion and cetylpyridinium chloride profiles. No sulphated glycosaminoglycans were detected.
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  • 5
    ISSN: 1432-0827
    Keywords: Proteoglycan ; Glycosaminoglycans ; Dentine ; Fluoride ; Biomineralization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Abstract Proteoglycans and their spatial arms, the glycosaminoglycans, are known to interact with hydroxyapatite, and are considered to have a role in the regulation of mineralization. This study investigates the interactive mechanisms, with particular attention directed at the influence of fluoride on the adsorption process. Proteoglycans and glycosaminoglycans were adsorbed to hydroxyapatite in the presence of fluoride (1–20 ppm range). The adsorbates included a chondroitin 4-sulfate-rich proteoglycan extracted from rat incisor dentine, hyaluronan, chondroitin 4-sulfate, and dermatan sulfate. The order of glycosaminoglycan in decreasing affinity for hydroxyapatite was chondroitin 4-sulfate, dermatan sulfate, and hyaluronan, and the individual glycosaminoglycans showed different responses to the presence of fluoride. Graded increases in fluoride (1–4 ppm) led to 5–40% reduction of glycosaminoglycan adsorption to hydroxyapatite. The proteoglycan showed less affinity for hydroxyapatite, and demonstrated a reduction in adsorption of up to 22% with 20 ppm fluoride. The inhibitory effect of fluoride indicated an electrostatic mechanism, presumably via the calcium sites in the hydroxyapatite lattice.
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  • 6
    ISSN: 1432-0827
    Keywords: Fluoride ; Proteoglycans ; Odontoblasts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Using an in vitro rat incisor odontoblast system, the effect of fluoride on proteoglycans was investigated at both the metabolic and structural level. Incisors were removed from 4-week-old rats, split longitudinally, and the pulps removed. Teeth were incubated at 37°C, 5% CO2 in Eagle's Minimum Essential Medium containing 35S-sulfate for 7 hours in the presence of 0 mM, 3 mM, or 6 mM sodium fluoride. Teeth were demineralized in EDTA, proteoglycan was extracted from the residue with 4 M guanidinium chloride, and further purified by anion exchange chromatography. Uptake of radiolabel was monitored by liquid scintillation counting. The resultant products were examined by cellulose acetate electrophoresis, SDS-PAGE, chondroitinase digestion, and amino acid analysis. Differential effects of fluoride were observed in both metabolism and biochemical characterization of proteoglycans following incubation at the two concentrations. Fluoride decreased uptake of the radiolabel but led to an accumulation of glycosaminoglycan within the proteoglycan of the matrix. Chondroitin sulfate was the predominant glycosaminoglycan identified, with the additional presence of dermatan sulfate and heparan sulfate identified. Dermatan sulfate levels increased in 3 mM-treated teeth. Fluoride-treated proteoglycans had a reduced molecular weight (200–90K to 180–79K); this reduction is primarily a result of smaller glycosaminoglycan chains, with limited reduction in the size of the core protein of 6 mM-treated teeth occurring. Such alterations in the biochemical metabolism and hence structure and function of proteoglycan may be implicated in the hypomineralization seen in fluorosis.
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  • 7
    ISSN: 1432-0827
    Keywords: Pulp ; Dentin ; Chondroitin ; Sulphate ; Biosynthesis ; Isotope
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Des rats Wistar, âgés de six semaines, sont injectés par voie intrapéritonéale avec du (35S) sulfate de sodium. Les animaux sont sacrifiés après 1 h et les molaires sont extraites. La pulpe et le dentine sont isolées par flottation différencielle et les glycosaminoglycanes sont étudiés après décalcification et protéolyse. L'étude du produit par électrophorèse sur acétate de cellulose montre la présence d'un composant métachromatique simple qui est radioactif. Des analyses chimiques, la spectroscopie infra-rouge et la réactivité aux enzymes permettent d'identifier le produit comme du sulfate 4′ chondroitine. Les résultats apportent une preuve chimique directe de l'incorporation rapide du (35S) sulfate de sodium dans les glycosaminoglycanes sulfatés de la matrice organique de molaires de rats. Ce tissu est un modèle intéressant pour l'étude du métabolisme de la substance fondamentale du tissu conjonctif.
    Abstract: Zusammenfassung Sechs Wochen alte Wistar-Ratten erhielten Natrium-[35S]-Sulfat intraperitoneal. Die Tiere wurden 1 Std nach der Injektion getötet, und ihre Backenzähne wurden extrahiert. Pulpa und Dentin wurden mittels der Differential-Flotation isoliert und auf Glycosaminoglycane nach Entkalkung und Proteolyse untersucht. Die Prüfung des Produktes mittels Zellulose-Acetat-Elektrophorese zeigte die Anwesenheit einer einzigen metachromatischen Komponente, welche radioaktiv war. Chemische Analyse, Infrarot-Spektroskopie und enzymatische Spaltbarkeit erlaubten die Identifikation des Produktes als Chondroitin-4′-Sulfat. Die Resultate liefern den direkten chemischen Beweis, daß Natrium-[35S]-Sulfat rasch in die sulfatierten Glycosaminoglycane der organischen Matrix der Ratten-Backenzähne eingebaut wird und daß dieses Gewebe ein nützliches Modell ist, um den Stoffwechsel der Grundsubstanz des Bindegewebes zu untersuchen.
    Notes: Abstract Six-weeks-old Wistar rats were injected intraperitoneally with sodium [35S]sulphate. The animals were sacrificed after 1 h and the molar teeth were extracted. The pulp and dentine were isolated by differential flotation and examined for glycosaminoglycans following decalcification and proteolysis. Examination of the product by cellulose acetate electrophoresis revealed the presence of a single metachromatic component which was radioactive. Chemical analysis, infrared spectroscopy and enzymic susceptibility identified the product as chondroitin 4′ sulphate. The results provide direct chemical evidence that sodium [35S]sulphate is rapidly incorporated into the sulphated glycosaminoglycans of the organic matrix of the rat molar tooth and that this tissue is a useful model for investigating the metabolism of the connective tissue ground substance.
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  • 8
    ISSN: 1600-0501
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Previous studies have indicated that examination of glycosaminoglycans (GAG) present in peri-implant sulcus fluid (PISF) may be a useful indicator of metabolic activity of the supporting bone. The GAG content in PISF from osseointegrated implants ad modum Bråemark in the maxilla was quantified and analysed. The study comprised 2 groups with 10 patients in each group. In one group the patients wore removable prostheses; in group 2 the patients wore fixed prostheses. The groups were matched for age, sex and function period of their prosthetic appliances. Clinical data were recorded, and the levels of the GAG hyaluronan (HA) and chondroitin-4-sulphate (C4S) were assessed using cellulose acetate electrophoresis and densitometric scanning of Alcian blue-stained strips against known GAG standards. PISF volumes and levels of C4S as potential bone marker showed no significant difference both groups median 0.003 μg). There was a somewhat higher median value for HA (0.015 μg) in the group of patients with removable prostheses compared with the group with fixed prosthesis =0.008 μg)(NS). HA is known to be present in high amounts in gingival tissue. As both plaque index and gingival bleeding were more frequent in patients with removable prostheses, this may be the reason for the somewhat higher value for HA in this group of patients. The difference in biomechanical properties of fixed and removable prostheses on implants do not appear to be reflected in the bone responses as measured by GAG content in PISF.
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  • 9
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    ISSN: 1600-0765
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Glycosaminoglycan (GAG)and proteoglycans (PG)were extracted from both relatively uninflamed and severely inflamed human gingiva. The constituent GAG, Hyaluronic acid, dermatan sulphate and chondroitin 4′ sulphate, were present in the same total amount and porportions in both tissues. In contrast the PG underwent substantial breakdown in the serverly inflamed tissue as judged by anion exchange chromatography and cellulose acetate electophoresis. The findings indicate theat whereas the GAG remain apparently unchanged during inflammation, the protein moiety of the PG is catabolised leading to a loss of structural integrity.
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  • 10
    ISSN: 1600-0501
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: The presence of certain glycosaminoglycans in peri-implant sulcus fluid may be an effective means of monitoring changes in bone metabolic activity following initial loading of implant abutments. This study has investigated levels of chondroitin 4 sulphate and hyaluronan in peri-implant sulcus fluid from titanium osseointegrated implants following initial abutment placement and exposure to masticatory stresses. Abutments were placed after a 3-month osseointegration period post-initial surgical placement of the interosseous stage. 10 edentulous patients, each with 5 mandibular implants were reviewed at 2, 4, 6 and 8 days after abutment placement. Clinical details were assessed and recorded and sulcus fluid collected in microcapillary tubes for a 5-min period for each abutment. Levels of glycosaminoglycans were assessed using cellulose acetate electrophoresis and densitometric scanning of alcian blue stained strips against known glycosaminoglycan standards. Maximum levels of sulcus fluid (0.3–1.25 /5 min) were evident at 4 days with a decrease towards 8 days. Levels of sulphated glycosaminoglycans were also maximal at 2–4 days (range 0.03–0.126 μg/5 min) and decreased at 6-8 days. Hyaluronan was detected within a similar range of values reaching maximal levels at 4 days and decreasing by 8 days. The results indicate that glycosaminoglycan levels of peri-implant sulcus fluid is an effective means of measuring and maintaining changes in bone metabolism. The absence of proteodermatan sulphate precludes 1 soft tissues being a source of these markers.
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