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Results 401 - 450 of 1478
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Eklund E - - 2000
The biosynthesis of dermatan sulfate is a complex process that involves, inter alia, formation of L-iduronic acid residues by C5-epimerization of D-glucuronic acid residues already incorporated into the growing polymer. It has been shown previously that this reaction is promoted by the presence of the sulfate donor 3'-phosphoadenosine-5'-phosphosulfate. In the ...
Spiro M J - - 2000
The occurrence of sulfate substituents on several positions of glycoprotein N-linked oligosaccharides prompted us to determine the subcellular localization and temporal relationships of the addition of these anionic groups employing as a model system the hemagglutinin (HA) produced by influenza virus-infected Madin-Darby canine kidney (MDCK) cells. It became apparent from ...
Ludmir J - - 2000
The human uterine cervix undergoes extensive changes during pregnancy. Collagen is reorganized and consolidated early in gestation with proliferation and hyperplasia of the cellular component. As term approaches, multiple factors work together in complex interactions that cause collagen dispersion and the cervix to ripen (clinically become softer). Increases in decorin ...
Ovens A - - 2000
Procollagen C-proteinase (PCP) is essential for the cleavage of procollagen to collagen in the extracellular matrix of animals and is, therefore, of major relevance to studies of ectopic deposition of collagen during fibrosis. In this study, we describe the design and synthesis of acidic side chain hydroxamate dipeptide inhibitors of ...
Naji L - - 2000
We have investigated the molecular motions of polysaccharides of bovine nasal and pig articular cartilage by measuring the 13C NMR relaxation times (T1 and T2). Both types of cartilage differ significantly towards their collagen/glycosaminoglycan ratio, leading to different NMR spectra. As chondroitin sulfate is the main constituent of cartilage, aqueous ...
Calik P - - 2000
A mass flux balance-based stoichiometric model for human liver metabolism has been set up. The model considers 125 reaction fluxes, and there are 83 metabolites that are assumed to be in pseudo-steady state. Theoretical metabolic flux distributions in the fibrotic and healthy liver cells were determined by maximizing respectively the ...
Borean A - - 2000
We monitored the efficacy of therapy with clodronate, a bisphosphonate drug, in women with postmenopausal osteoporosis, using urinary immunoenzymatic assay of C-telopeptide of collagen type I, an eight amino acid fragment (collagen fragment) of the C-telopeptide of the alpha1-chain of collagen type I (EKAHDGGR). The analysis of the dynamics of ...
Slatter D A - - 2000
Malondialdehyde (MDA) is a highly toxic by-product formed in part by lipid oxidation derived free radicals. Many studies have shown that its concentration is increased considerably in diabetes mellitus. Malondialdehyde reacts both irreversibly and reversibly with proteins and phospholipids with profound effects. In particular, the collagen of the cardiovascular system ...
Iijima K - - 2000
Collagen undergoes continuous non-enzymatic glycation during its long life period. The products resulting from the glycation reaction, so-called advanced glycation end products (AGEs), were regarded as potential pathogens of various diseases such as diabetic complications. Although several AGEs were identified from acid hydrolysates of glycated collagen, the major AGE(s) responsible ...
Lee K B - - 2000
Chondroitin sulfates proteoglycans were isolated from human placenta. For the identification of enzymatic digestion products of isolated proteoglycan, strong anion, exchange-high performance liquid chromatography (SAX-HPLC) was performed. By the action of chondroitin ABC and chondroitin B lyase, three unsaturated disaccharides 2-acetamide-2-deoxy-3-O-(beta-D-gluco-4-enepyranosyluronic acid)-D-galactose (deltaDi-OS), 2-acetamide-2-deoxy-3-O-(beta-D-gluco-4-enepyranosyluronic acid)-6-O-sulfo-D-galactose (deltaDi-6S) and 2-acetamide-2-deoxy-3-O-(beta-D-gluco-4-enepyranosyluronic acid)-4-O-sulfo-D-galactose (deltaDi-4S) ...
Chavante S F - - 2000
With the aid of heparinase and heparitinases from Flavobacterium heparinum and 13C and IH NMR spectroscopy it was shown that the heparan sulphate isolated from the brine shrimp Artemia franciscana exhibits structural features intermediate between those of mammalian heparins and heparan sulphates. These include an unusually high degree of N-sulphation ...
Yoshimura K - - 2000
Alkali-solubilized collagens, prepared by alkali-acid extraction and alkali direct extraction (abbreviated AASC and ALSC, respectively), were characterized by dynamic viscoelastic measurement of collagen solution (10 mg/mL). The optimum preparative conditions in terms of yield and polypeptide size are as follows: for the alkali-acid extraction, a pretreatment with 0.5 or 1 ...
Chevallay B - - 2000
Many substances are used in the production of biomaterials: metals (titanium), ceramics (alumina), synthetic polymers (polyurethanes, silicones, polyglycolic acid (PGA), polylactic acid (PLA), copolymers of lactic and glycolic acids (PLGA), polyanhydrides, polyorthoesters) and natural polymers (chitosan, glycosaminoglycans, collagen). With the rapid development in tissue engineering, these different biomaterials have been ...
Agee K - - 2000
The purpose of this study was to evaluate the efficacy of a number of additives to acid conditioners at reducing the denaturation of dentine collagen. Dentine collagen is normally not very susceptible to trypsin attack. After denaturation, however, it becomes more susceptible to the action of trypsin. Slabs of human ...
Brown E M - - 2000
The thermal stability of acid-soluble collagens was studied by circular dichroism (CD) spectroscopy. Adult bovine dermal collagen (BDC), rat-tail tendon collagen (RTC), and calf skin collagen (CSC) were compared. Despite some variability in amino acid composition and apparent molecular weight, the CD spectra for helical and unordered collagen structures were ...
Bailey A J - - 2000
The fate of collagen implants in a wound environment is determined by the host response they elicit, their accommodation for cellular infiltration and their susceptibility to proteolytic attack. Glutaraldehyde cross-linking is most effective in delaying resorption and reducing an antibody response. The proteolytic events reflect the sequence of cellular infiltration ...
Cloos P A - - 2000
Mature tooth dentin has essentially no metabolic activity, and thus post-translational modifications accumulate with aging in this tissue. In the present paper, we have studied age-related covalent changes of human dentin proteins. Dentin phosphorproteins (PP) were extracted and purified using ion exchange chromatography. Collagen was purified by CNBr cleavage and ...
Li Y - - 2000
The effect of a methanol extract of Eucommiae Cortex on collagen synthesis was investigated in false aged model rats. Granuloma formation and collagen synthesis were significantly increased by the administration of the methanol extract of Eucommiae Cortex. The effective component of Eucommiae Cortex was then discussed by fractionating the methanol ...
Kunou M - - 2000
Colominic acid, an alpha (2-->8)-linked poly(sialic acid), was sulfated and characterized by NMR spectroscopy. During sulfation, the secondary hydroxyl group at C-4 had almost the same reactivity as the primary hydroxyl group at C-9, while the secondary hydroxyl group at C-7 was hardly substituted. Analysis by molecular modeling suggested that ...
Adamczyk M - - 2000
(+)-Deoxypyridinoline (Dpd, 2) is a cross-link of bone collagen, which is released and excreted in urine during process of bone resorption. It has been shown that this bone collagen degradation product, Dpd (2) is a useful marker for diagnosis of osteoporosis and other metabolic bone diseases. In this paper, the ...
Martin R E - - 1999
PURPOSE: Lysophosphatidic acid induces neurite retraction; it is also present in tears and aqueous humor. We determined whether lysophosphatidic acid induces HSV-1 reactivation in latently infected rabbits and whether the nerve growth associated protein GAP-43 undergoes posttranslational modification during the course of HSV-1 infection. METHODS: Rabbits were infected with HSV-1 ...
Trier K - - 1999
AIMS: To examine a possible effect of 7-methylxanthine, theobromine, acetazolamide, or L-ornithine on the ultrastructure and biochemical composition of rabbit sclera. METHODS: Groups of pigmented rabbits, six in each group, were dosed during 10 weeks with one of the substances under investigation, and one untreated group was the control. Samples ...
Palace G P - - 1999
Determination of amino acids in polymers with varying structure and charge was performed using vapor phase acid hydrolysis and subsequent precolumn derivatization with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC). Percent load of neutral, cationic and anionic peptide-modified synthetic polymers was accurately determined using this technique. Assay utility was shown for glycosaminoglycans and other ...
Takada Y - - 1999
Ultrastructural aspects of hypertrophic chondrocytes in hamster and mouse epiphysial cartilage were examined in relation to their metabolic activities. With the hypertrophic change, cytoplasmic vacuolization proceeded leaving the partially intact endoplasmic reticulum (ER). In the hypertrophic cells, cytoplasmic hyaluronan was stained with the biotinylated hyaluronan-binding region (b-HABR) of aggrecan, and ...
Zanetta J P - - 1999
A major impediment in the analysis of glycosaminoglycans is the difficulty to cleave quantitatively the glycosidic bonds because of the stabilisation of glycosidic bonds and of the relative instability of the liberated constituents. This manuscript describes a modified procedure of methanolysis in the presence of barium acetate, reducing the destruction ...
Yamamoto K - - 1999
Hair follicles develop or regress in accordance with the hair cycle. In this study, we partially characterized fibrillar type I collagen, the predominant component in the dermis, at two stages of the hair cycle: anagen and telogen. Skin samples were obtained from the backs of two groups of 11-week-old C3H ...
Kim S - - 1999
The N-terminal portion (amino acids 1303-1367) of the type 1 ryanodine receptor D2 region is thought to be critical for excitation-contraction coupling in skeletal muscle. A segment of the D2 region (amino acids 1317-1355) was expressed as a glutathione S-transferase fusion protein (GST-D2) and then crystallized at room temperature using ...
Tsutsumi Y - - 1999
By immunoperoxidase analysis for types I to VI collagen, elastin, cytoskeletal components and some glycoproteins, we found type VI collagen immunoreactivity in amorphous eosinophilic deposits (skeinoid fibers) in three small intestinal stromal tumors. Negative results were obtained for types I, II, III, IV and V collagen, elastin, laminin, ubiquitin, intracellular ...
Oda Y - - 1999
Colominic acid is an alpha2,8-linked sialic acid polymer produced by Escherichia coli. We found that synthetic sulfated-colominic acids (SC) remarkably inhibited the cytotoxicity of bee and snake venom toward mouse fibroblast cells, but colominic acids showed no inhibition themselves, indicating the important role of sulfate groups in the inhibitory activity ...
Natsir N - - 1999
This study examined the effect of tannic acid solution on dissolution of dentine collagen and morphological aspects of tendon collagen. Using root dentine, which was cut off from bovine anterior tooth, dentine powders were obtained by the pulverization and lyophilization. They were subject to an application of 1, 3, 5 ...
Tsuda T - - 1999
BACKGROUND: Human amnion has useful biomedical applications because it contains a large amount of human collagen fibers. We prepared purified human collagen membrane (HCM) from human amnion and used it to develop a new sheet by combining it with synthetic bioabsorbable polyglycolic acid (PGA) mesh. We evaluated its efficacy in ...
Kovensky J - - 1999
It has been suggested that the FGF-2 binding site on heparan sulfate chains is a trisulfated pentasaccharide containing three hexuronic acid units. The configuration at C-5 of two of them being undetermined, we have synthesized the four possible pentasaccharides, and have evaluated their FGF-2 binding affinity through in vitro biological ...
Slatter D A - - 1999
Malondialdehyde is a product of fatty acid oxidation (e.g. from low density lipoprotein) implicated in the damage of proteins such as collagen in the cardiovascular system (Chio, K. J., and Tappel, A. L. (1969) Biochemistry 8, 2821-2827). Its concentration is raised in diabetic subjects probably as a side effect of ...
Vidmar J J - - 1999
A cDNA, hvst1, was isolated from Hordeum vulgare by heterologous complementation in Escherichia coli. This cDNA encodes a high-affinity sulfate transporter that is 2442 bp in length and consists of 660 amino acids. Under steady-state conditions of sulfate supply during culture, sulfate influx (measured at 100 microM external sulfate concentration) ...
Ioannidis N - - 1999
High concentrations of fulvic acid and selenium deficiency in drinking water are the main causative factors of Kashin-Beck disease, an endemic degenerative chronic osteoarticular disorder found in China. The influence of fulvic acid on collagen secretion was investigated in articular chondrocyte cultures from bovine interphalangeal joints. Collagen secretion in 7-day-old ...
Suzuki Y - - 1999
Collagen type I extracted with acid or digested with pepsin forms fibrils under physiological conditions, but this ability is lost when the collagen is treated with alkaline solution or digested with matrix metalloproteinase 1 (MMP1). When acid-soluble collagen was incubated with alkali-treated collagen, the fibril formation of acid-soluble collagen was ...
Nadanaka S - - 1999
A novel sulfotransferase activity was discovered in fetal bovine serum using pig skin dermatan sulfate as an acceptor and [35S]3'-phosphoadenosine 5'-phosphosulfate as a sulfate donor. The enzyme was separated from chondroitin:GalNAc 6-O-sulfotransferase by chromatographic techniques. Enzymatic analysis of the reaction products demonstrated that the enzyme transferred sulfate to the C6 ...
Li Y - - 1999
We earlier reported that collagen synthesis in false aged model rats was stimulated by the administration of a methanol extract from the leaves of Eucommia ulmoides OLIVER. When the methanol extract was fractionated to n-hexane, ethyl acetate, acetone and methanol fractions by silica gel chromatography, we discovered that geniposidic acid ...
- - 1999
Glucosamine sulfate's role in halting or reversing joint degeneration appears to be directly due to its ability to act as an essential substrate for, and to stimulate the biosynthesis of, the glycosaminoglycans and the hyaluronic acid backbone needed for the formation of the proteoglycans found in the structural matrix of ...
Johnson K A - - 1999
Collagenous xenografts made from kangaroo tail tendon cross-linked with glutaraldehyde have a potential application in the reconstruction of massive digital tendon deficits. However, a limitation to the clinical use of these xenografts has been the optimization of collagen cross-linking, and subsequent bio-incorporation and retention of mechanical properties following implantation. The ...
Maquart F X - - 1999
Titrated Extract from Centella asiatica (TECA) is a drug which has been used for many years in Europe for the treatment of wound healing defects. It is a reconstituted mixture of 3 triterpenes extracted from the plant, asiatic acid, madecassic acid and asiaticoside. In this report, we studied the effects ...
Watanabe M - - 1999
Elastic fiber is one of the major component of the extracellular matrix, which provides the resilience to many tissues. Elasticity is an important property of human aorta, and this elastic property decreases in various pathological conditions such as dissecting aneurysm (DA). Since the cross-linking structures in elastin are responsible for ...
Notbohm H - - 1999
Type II collagen is the main structural component of hyaline cartilages where it forms networks of thin fibrils that differ in morphology from the much thicker fibrils of type I collagen. We studied here in vitro the formation of fibrils of pepsin-treated recombinant human type II collagen produced in insect ...
Euli D - - 1999
An accurate method for the determination of collagen to study its distribution and turn-over in different tissues is described. 5-Hydroxylysine (5Hylys) is an amino acid that is apparently present in no other protein except collagen and, as it is metabolised only to a minor degree compared with 4-hydroxyproline (4Hypro), it ...
Jorge-Herrero E - - 1999
The use of biological materials in the construction of bioprostheses requires the application of different chemical or physical procedures to improve the mechanical performance of the material without producing any undesirable effects. A number of cross-linking methods have been tested in biological tissues composed mainly of collagen. The basis for ...
Moon S E - - 1999
BACKGROUND: Several clinical reports have suggested that alpha hydroxy acids (AHAs), including glycolic acid, may improve photoaging. However, the mechanism of action of glycolic acid is not well understood. OBJECTIVE: In order to investigate the mechanism of action of glycolic acid in improving photoaged skin, we observed the effect of ...
Chatziioannidis C C - - 1999
A minor low-sulphated dermatan sulphate proteoglycan was isolated from ray skin by extraction with 2% sodium dodecyl sulphate, followed with ion-exchange chromatography, gel chromatography and density gradient centrifugation. The proteoglycan with a relative molecular mass (Mr) ranging from 70 to 120 kDa is composed of about two dermatan sulphate chains ...
Volpi N - - 1999
The stability of chondroitin sulfate (CS) was studied under acidic, neutral and basic conditions at 30 and 60 degrees C. CS is remarkably stable under neutral conditions at low temperature, while it degrades at 60 degrees C producing low-molecular-mass fragments and desulfated products. This decomposition process begins at ca. 500-600 ...
Bakos D - - 1999
The new composite biomaterial made from hydroxyapatite and collagen conjugated with hyaluronic acid has been studied. The structure evaluation of the composite showed more dense arrangement due to the formation of collagen hyaluronic acid conjugate, and particles of inorganic component are closely anchored in the structure. Mechanical properties and model ...
Ishiguro N - - 1999
OBJECTIVE: To investigate the correlation between synovial fluid (SF) concentrations of metalloproteinase (MMP) -2, -3, and -9, tissue inhibitors of metalloproteinases (TIMP)-1 and -2, chondroitin 4-, 6-sulfate (deltadi-C4S, deltadi-C6S), hyaluronic acid (deltadi-HA), antigenic keratan sulfate (KS), and radiologic grade in patients with rheumatoid arthritis (RA) and to assess the clinical ...
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