Biomedical subjects

G Embery

Publications and source records attributed to G Embery.

At least 37 records · Page 2Linked to original sources

PubMed2000

The isolation and detection of non-collagenous proteins from the compact bone of the dinosaur Iguanodon.

This report describes the isolation of guanidinium chloride extractable protein from demineralised bone extracts obtained from the 125-130 mya dinosaur Iguanodon. Protein products were isolated in the Mr. range 5,000-66,000 using SDS-PAGE and represent the first electrophoretically defined proteins isolated from dinosaur tissues. The levels of glycine, aspartate and serine tentatively suggest the presence of phosphoproteins. Hydroxylysine and hydroxyproline were not detected, confirming the presence of non-collagenous material. In addition the absence of ornithine confirmed lack of bacterial contamination. The relatively high level of leucine in the 2MNaCl NaCl fractions together with the abolition of alcian blue reactivity following protease-free chondroitinase digestion suggests the presence of proteoglycans. The study is of interest in describing the early proteins laid down in mineralised tissues for epitactic crystal growth and may provide evidence on evolutionary aspects of bone proteins.

Animals↗

PubMed1999

Altered phosphorylation of rat dentine phosphoproteins by fluoride in vivo.

Dentine phosphoproteins have been proposed to have an important role in mineralization. This study focused on the influence of fluoride on the biochemical composition of dentine phosphoproteins and attempts to relate changes to the altered mineralization witnessed during fluorosis. Wistar rats were rendered fluorotic by the administration of 20 ppm sodium fluoride in their drinking water ad libitum, a nonfluorotic group received double-distilled, deionized water only. After 17 weeks, the teeth showed signs of fluorosis. The incisors were removed, split longitudinally, and the pulps were removed. Teeth were powdered and demineralized in 10% EDTA with protease inhibitors, after which the organic matrix was extracted with 4 M guanidinium chloride. Phosphoproteins were selectively precipitated from the soluble extract by the addition of 1.0 M calcium chloride and further purified by anion exchange chromatography. SDS-PAGE revealed two protein bands with molecular weights of 130 kDa and 66 kDa in the nonfluorotic fraction and 116 kDa and 66 kDa in the fluorotic fraction. Western blotting analysis identified the 66 kDa band as alpha2-HS glycoprotein which co-precipitated with phosphoproteins. Electroelution of the protein bands was performed with subsequent biochemical analyses. Phosphate content was determined for each protein band and was detectable in the 116 kDa and 130 kDa bands from the fluorotic and nonfluorotic samples, respectively, with a decreased level noted in the 116 kDa band. The presence of phosphate and the amino acid analysis of these bands suggested their identity to be dentine phosphoproteins. No changes in the ratio of amino acids was detected in fluorotic samples. The fluoride-induced alterations to the biochemical structure of dentine phosphoproteins would appear to influence the phosphorylation of these macromolecules only, possibly affecting posttranslational events. Such alterations may play a role in disrupting the patterns of mineralization seen during fluorosis.

Amino Acids↗

PubMed1999

Adsorption of glycosaminoglycans onto hydroxyapatite using chromatography.

Proteoglycans are known to play an important role in the mineralization process, acting either as promoters or inhibitors. In this study the binding affinity of a variety of constituent glycosaminoglycan to hydroxyapatite was studied. Glycosaminoglycans (10-1000 microg ml(-1) in 0.02 M sodium acetate (pH 6.8) were constantly circulated through a hydroxyapatite column for 1 h. The total amount of glycosaminoglycan bound was determined by dimethylmethylene blue assay. The relative affinities of the different glycosaminoglycans remaining bound to hydroxyapatite was investigated by examining their release in a 0-1 M sodium phosphate gradient. Differences were noted between the desorption profiles of dermatan sulfate with two elution peaks and chondroitin 4-sulfate and chondroitin 6-sulfate each with a single peak. Dermatan sulfate and chondroitin 6-sulfate had a higher affinity for hydroxyapatite than chondroitin 4-sulfate possibly due to the presence of differing di-sulfated disaccharide ratios in the glycosaminoglycan chains. These findings suggest the presence of a variety of binding forms of each glycosaminoglycan or the differing orientation of these forms to yield different complexes with hydroxyapatite. The Ca2+ co-ordinates of the glycosaminoglycans are known to vary and may in part explain these findings.

Adsorption↗

PubMed1999

Stromelysin-1 (MMP-3) in forming enamel and predentine in rat incisor-coordinated distribution with proteoglycans suggests a functional role.

Stromelysin-1 (matrix metalloproteinase-3) or proteoglycanase was visualized by light and electron microscopy immunolabelling in the forming zone of rat incisors. In predentine, labelling was more dense at the transition zone between the inner proximal third and the two outer thirds. Odontoblast processes were also positively stained, mostly in predentine and to a lesser degree in dentine. The dentine-enamel junction was intensely labelled, whereas dentine and forming enamel were only faintly stained. Gold-antibodies complexes were seen inside secretory ameloblasts and odontoblasts in cytosolic locations. The distribution of stromelysin-1 was compared with the distribution of 2-B-6 epitope, an antibody recognizing chondroitin-4-sulphate/dermatan sulphate and which showed a decreasing gradient from the proximal zone to the distal part of predentine. In contrast, both 5-D-4, an anti-keratan sulphate antibody and an anti-lumican antibody displayed a reversed distribution, with an increase seen from the proximal and central thirds to the distal part of predentine. This coordinated distribution suggests that stromelysin-1 may have a functional role, being implicated in predentine in the degradation of chondroitin-4-sulphate/dermatan sulphate-containing proteoglycans, and consequently allowing keratan sulphate proteoglycan concentration to increase near the border where mineralization is initiated.

Ameloblasts↗

PubMed1999

Effect of environmental haemin upon the physiology and biochemistry of Prevotella intermedia R78.

The effect of environmental haemin on the physiology and biochemistry of Prevotella intermedia R78 grown in batch culture was assessed. Extent and rate of growth increased as the environmental haemin concentration was raised. In addition, cell morphology was predominantly cocco-bacillary when cultured in high haemin environments, while bacillary forms were prevalent in low haemin conditions (< 2.5 mumol l-1). Cells harvested from low haemin environments produced greater numbers of extracellular vesicles and greater amounts of peptidolytic activity, haemagglutinating potential and haemin binding activity when compared with cells harvested from high haemin conditions. The results of the present study indicate that aspects of the biochemistry and physiology of P. intermedia are influenced by changes in environmental haemin levels.

Culture Media↗

PubMed1999

The proteoglycans of human cementum: immunohistochemical localization in healthy, periodontally involved and ageing teeth.

Cementum is believed to play a regulatory role in periodontal regeneration through a variety of macromolecules present in its extracellular matrix (ECM), among which are the proteoglycans (PG). The PG of human cementum have not been fully characterized. This study has used a standard indirect immunoperoxidase technique to investigate the presence and distribution of PG species within the ECM of human cementum. Freshly extracted human permanent teeth were separated into 8 age groups; each group was subdivided to include healthy and periodontally involved teeth, which were then fixed, demineralized and wax-embedded. Sections were incubated with polyclonal antibodies recognizing protein core epitopes in the large chondroitin sulphate PG versican and the small interstitial PG decorin, biglycan, fibromodulin and lumican. Immunoreactivity to versican, decorin, biglycan and lumican was evident at the borders and lumina of a proportion of lacunae and canaliculi surrounding cementocytes in cellular cementum, as well as on inserted periodontal ligament (PDL) fibres. Biglycan was also present along incremental lines in cellular cementum, whereas staining for fibromodulin was negative. In acellular cementum, no immunoreactivity was evident with any of the antibodies used except on inserted PDL fibres. These results indicate that versican, decorin, biglycan and lumican are components of the ECM of cellular, but not of acellular cementum. Neither age nor periodontal diseases appear to qualitatively influence the PG population of cementum. The distribution of PG epitopes around a proportion of cementocytes suggests the existence of different cementocyte subpopulations, or a differential response of these cells to yet undefined stimuli.

Adolescent↗

PubMed1998

Immunochemical detection of the proteoglycans decorin and biglycan in human gingival crevicular fluid from sites of advanced periodontitis.

This study characterized proteoglycan metabolites present in gingival crevicular fluid (GCF) collected from sites with clinical evidence of advanced periodontal disease. The metabolites were purified by anion-exchange chromatography from which a chondroitin sulphate rich fraction was identified by cellulose acetate electrophoresis. Sodium dodecylsulphate-polyacrylamide gel electrophoresis of this fraction revealed a broad silver-staining band with mol. wt 55-65 k and Western blotting suggested that this band was immunoreactive with CS-56, a monoclonal antibody for chondroitin sulphate. Digestion of the metabolite with chondroitinase ABC (protease-free) led to the loss of the silver-staining band. Dot-blot analysis identified components in this fraction that were immunoreactive for the monoclonal/polyclonal antibodies against the C-termino of decorin and biglycan. Amino acid analysis revealed the composition of the proteoglycan metabolite to be rich in glycine, serine and glutamic acid. Immunochemical and biochemical analyses were compared with those of proteoglycan purified from human alveolar bone. Changes in the amino acid composition were noted, suggesting the proteoglycan metabolite has undergone extensive modification and fragmentation to the protein core. The results suggest that the proteoglycan metabolite from GCF represented a degradation product originating from the active destruction of the alveolar bone. They provide further support for the proposal that the appearance of proteoglycan metabolites in GCF is a biomarker for active destruction of alveolar bone, the biochemical analysis of which provides important information on mechanisms involved in the pathology of periodontal diseases.

Adult↗

PubMed1998

Immunolocalization of glycosaminoglycans in ageing, healthy and periodontally diseased human cementum.

The distribution of glycosaminoglycans in the extracellular matrix of human cementum was investigated in periodontally involved and periodontal disease-free teeth separated into eight different age groups (from 12 to 90 years), to investigate possible changes in the distribution of glycosaminoglycan species associated with ageing and periodontal disease. A standard indirect immunoperoxidase technique was used, with a panel of monoclonal antibodies, 2B6, 3B3, 5D4, and 7D4, that recognize epitopes in chondroitin-4-sulphate/dermatan sulphate (C-4S/DS), chondroitin-6-sulphate (C-6S), keratan sulphate (KS) and a novel sulphated chondroitin sulphate (CS) epitope, respectively. Intense positive staining for C4-S/DS was observed at the margins and lumina of almost all the lacunae and canaliculi in cellular cementum in all sections. Immunoreactivity to C6-S, KS and novel CS epitopes was limited to a proportion of lacunae and canaliculi in all sections, although C6-S and the novel CS epitopes were more widely distributed than KS. In acellular cementum, there was no demonstrable staining for any of the glycosaminoglycans except where periodontal ligament (Sharpey's) fibres insert; periodontal ligament fibres inserting in cellular cementum also demonstrated positive immunoreactivity. In addition, the cementoblasts on the outer root surface, as well as the pericellular areas around a proportion of these cells, demonstrated positive immunoreactivity. These results indicate that glycosaminoglycan species present in human cementum include C4-S, DS, C6-S, and novel sulphated CS epitopes. KS is also present in cementum but is limited to a more restricted proportion of lacunae and canaliculi. Regional differences in the distribution of glycosaminoglycans exist between the two cementum types, but no qualitative differences in that distribution were observed between the various age groups or between periodontally involved and periodontal disease-free teeth. The immunoreactivity observed in a proportion of lacunae after staining for C6-S, KS, and novel sulphated CS epitopes could suggest the existence of different cementocyte subpopulations.

Adolescent↗

PubMed1998

Quantitative immunohistochemical evidence of a functional gradient of chondroitin 4-sulphate/dermatan sulphate, developmentally regulated in the predentine of rat incisor.

A quantitative examination was carried out on the early and mature stages of dentinogenesis in the rat incisor, using a post-embedding immunogold labelling with an anti-chondroitin 4 sulphate/dermatan sulphate antibody (2B6). At a very early stage of predentine formation, before polarizing odontoblasts have established junctional complexes, immunolabelling was weak. In contrast, when polarized odontoblasts established distal junctional complexes, immunolabelling in predentine was uniform and threefold denser than in initial predentine. The same gold particle density was found in the non-mineralized mantle dentine. During circumpulpal dentine formation, a gradient was seen in predentine, a larger number of gold particles being scored in the proximal zone compared with the distal region adjacent to the mineralization front. In circumpulpal dentine, some labelling was found within the lumen of the tubules and in the bordering dentine around the tubules. A few particles were also detected in intertubular matrix after demineralization. Together, these data provide evidence for a developmentally regulated gradient during the transition between mantle and circumpulpal dentine, and also in a more mature part of the tooth, a functional gradient that probably plays a role in the process of mineralization.

Animals↗

PubMed1998

Calcium- and hydroxyapatite-binding properties of glucuronic acid-rich and iduronic acid-rich glycosaminoglycans and proteoglycans.

This study describes the interaction of a small chondroitin sulphate proteoglycan and the glycosaminoglycans chondroitin 4-sulphate, dermatan sulphate and heparan sulphate with hydroxyapatite. All macromolecules possessed a high affinity, with the iduronic acid-rich dermatan sulphate and heparan sulphate displaying higher adsorption maxima than the glucuronic acid-rich chondroitin 4-sulphate. At similar concentrations, dermatan sulphate produced a 30% inhibition of hydroxyapatite-induced crystal growth, whilst chondroitin 4-sulphate yielded 50% inhibition. Estimation of the calcium binding capacity of these glycosaminoglycans using equilibrium dialysis indicated that chondroitin 4-sulphate bound five times more calcium than dermatan sulphate at a calcium concentration similar to that of serum. The data indicate a possible important role for chondroitin 4-sulphate in dentinogenesis where it is the dominant glycosaminoglycan, since it could act as a capture point for calcium ions during mineralisation, with the leucine-rich domain of its parent proteoglycan acting as anchor points to type I collagen.

Adsorption↗

PubMed1998

The modification of alveolar bone proteoglycans by reactive oxygen species in vitro.

Reactive oxygen species (ROS) are being increasingly implicated in the connective tissue degradation associated with chronic inflammatory conditions, such as periodontal disease. The present study investigated the effects of ROS on the proteoglycans (PG) of alveolar bone which are important structural components within the periodontium. PG were isolated from ovine alveolar bone and exposed to increasing concentrations of hydrogen peroxide (H2O2) or to a hydroxyl radical (.OH) flux for 1 h or 24 h, and the degradation products examined for depolymerisation and chemical modification of the PG structure. ROS were demonstrated to be capable of degrading alveolar bone PG in vitro, the .OH species resulting in greater modification than H2O2. The degradative effects observed included cleavage of the protein core and depolymerisation of the GAG chains. The core proteins were more susceptible to degradation than the GAG chains in the presence of H2O2 alone, although both the core proteins and the GAG chains were extensively degraded in the presence of a .OH flux for both 1 h and 24 h. Exposure of the PG to .OH for 24 h resulted in significant modification to the amino acid composition with decreases in the proportion of leucine and the complete loss of proline, tyrosine and phenylalanine evident. The results highlight the potential role of ROS as an important mechanism in considering the pathology of periodontal tissue destruction.

Alveolar Bone Loss↗

PubMed1997

Degradation of glycosaminoglycans by reactive oxygen species derived from stimulated polymorphonuclear leukocytes.

The effect of reactive oxygen species (ROS), generated by in vitro stimulation of isolated PMN upon the main GAG components of mineralised and non-mineralised connective tissues was investigated. PMN were isolated from whole blood and the production of the ROS superoxide (O2.-) and hydroxyl radicals (.OH) was stimulated by the addition of phorbol myristyl acetate (PMA) and PMA/FeCl3-EDTA chelate respectively and their production assessed over a 24 h period. The glycosaminoglycans (GAG), hyaluronan, chondroitin 4-sulphate and dermatan sulphate, were exposed to the ROS fluxes, incubated at 37 degrees C for 1 h and 24 h. GAG fragmentation was examined by gel exclusion chromatography and modification to hexuronic acid and hexosamine residues determined. Stimulation of PMN with PMA resulted in a burst of O2.- production for 1 h, which was sustained at a reduced level for 24 h. Fragmentation of GAG was observed for all GAG examined. Modification to the GAG was evident, with hyaluronan being more susceptible to loss of GAG residues than sulphated GAG. Modification of sugar residues increased with the incubation time and loss of the hexuronic acid residues was greater than loss of hexosamine residues. Addition of FeCl3-EDTA chelate, which led to the generation of .OH and was sustained over the 24 h period, demonstrated similar trends of GAG modification although increased degradation and loss of hexosamine and hexuronic acid were observed. GAG chains are constituents of PGs and their modification is likely to affect the function of these macromolecules and be of importance in considering the pathogenesis of inflammatory diseases, including periodontal diseases.

Glycosaminoglycans↗

PubMed1997

The relationship between microbial factors and gingival crevicular fluid glycosaminoglycans in human adult periodontitis.

Counts of cultivable Porphyromonas gingivalis, assays of microbial proteases and the concentration in gingival crevicular fluid of proteoglycan metabolites were investigated at periodontitis and gingivitis sites in 16 patients with chronic adult periodontitis before and after treatment. Two periodontitis sites and two gingivitis sites were selected from each patient on the basis of a clinical examination. Gingival crevicular fluid from each site was analysed for the concentrations of the glycosaminoglycans chondroitin-4-sulphate and hyaluronan and subgingival plaque samples were analysed for cultivable P. gingivalis and microbial trypsin-like proteases assayed by benzoyl-DL-arginine-naphthylamide (BANA) hydrolysis. Significantly higher concentrations (p = 0.007) of chondroitin-4-sulphate were found at periodontitis than gingivitis sites but there was no significant difference in hyaluronan (p = 0.36) between these sites. Although the majority of periodontal sites were P. gingivalis-negative (23/32), there were significantly higher concentrations of chondroitin-4-sulphate (p = 0.05) and hyaluronan (p = 0.04) at the P. gingivalis-positive, compared to negative, periodontitis sites. At BANA-positive periodontitis sites there were also higher concentrations of chondroitin-4-sulphate (p = 0.0015) and hyaluronan (p = 0.0001) than at BANA-positive gingivitis sites. There was a significant decrease in concentrations of chondroitin-4-sulphate and hyaluronan at periodontitis sites after treatment. This study lends support to the hypothesis that P. gingivalis may be actively involved in the destruction of connective tissue components at culture-positive sites but shows that elevated concentrations of connective tissue breakdown products may occur in gingival crevicular fluid from periodontal sites where this organism is absent.

Adult↗

PubMed1997

Glycosaminoglycan biosynthesis during 5-fluoro-2-deoxyuridine-induced palatal clefts in the rat.

The biosynthesis and hydration of glycosaminoglycans (GAG) has been implicated in the generation of palatal shelf-elevating force(s) in mammals, although the nature of the palatal shelf extracellular matrices during cleft palate formation remains poorly understood. This study quantifies the GAG composition in the palatal shelves of Wistar rat fetuses at various periods of palatogenesis where clefts were induced experimentally using 5-fluoro-2-deoxyuridine (FUDR). For both normal and cleft palatal shelves, hyaluronan, heparan sulphate and chondroitin-4-sulphate were detected but not dermatan sulphate or chondroitin-6-sulphate. Throughout the period of cleft development studied, the total amount of GAG was significantly decreased (by approx. 30%) compared with normal development, this decrease being particularly marked at a time equivalent to post-elevation during normal development (approx. 75%). Furthermore, and unlike normal palatogenesis, no significant differences were recorded between the anterior and posterior parts of the palatal shelves during cleft formation. As for normal palatogenesis, however, the percentages of each GAG were not altered at any stage. The findings are consistent with the view that suppression of GAG biosynthesis is related to the development of cleft palate in FUDR-treated rat fetuses and can therefore be interpreted as providing evidence of a role for the mesenchymal glycoconjugates in shelf elevation during normal palatogenesis.

Animals↗

PubMed1997

Identification of a zinc-binding cystic fibrosis antigen in human saliva by 65Zn probing and N-terminal sequencing.

Human whole saliva was collected at 4 degrees C into a protein inhibitor cocktail to prevent proteolytic degradation. Saliva was clarified by centrifugation and fractionated by immobilized metal affinity chromatography (IMAC) after charging the column with zinc ions. Proteins with an affinity for zinc were eluted from the IMAC column, characterized by sodium dodecylsulphate-polyacrylamide gel electrophoresis, and probed with 65ZnCl2 after electrotransfer on to polyvinylidenefluoride membranes. A zinc-binding protein of approx. 11 kDa was characterized by N-terminal sequencing followed by a FASTA search of Genbank. The first 40 residues were sequenced, of which the first 34 residues were used to conduct a FASTA search and yielded and homology > 97% coding for sequences of mRNA of two proteins, a cystic fibrosis antigen with an M(r) of 10,938 and a calcium-binding inflammatory protein MRP8 with an M(r) of 10,835 expressed in chronic inflammation. The identity of the last 15 residues of the sequence and the likelihood that the protein is secreted via saliva indicates that the 11-kDa protein is the cystic fibrosis antigen, a protein not previously reported in saliva.

Amino Acid Sequence↗

PubMed1997

Adsorption of chondroitin-4-sulphate and heparin onto hydroxyapatite--effect of bovine serum albumin.

The adsorption of chondroitin-4-sulphate (C4S) and heparin onto hydroxyapatite (HA) has been studied in the absence and presence of bovine serum albumin (BSA). Isotherm data at pH 6.8 have shown that BSA in solution has no effect on C4S adsorption, whereas heparin affinity and adsorption decrease. These data suggest that C4S and BSA bind to different calcium sites on the HA surface. Heparin and BSA may compete for the same calcium sites, or alternatively form heparin-BSA complexes leading to less binding due to steric effects. Evidence of an interaction between heparin and BSA in solution has been shown in this study, there being negligible interaction for C4S. BSA adsorption from solution onto HA decreases with increasing C4S/heparin solution concentration, which may be due to glycosaminoglycan-induced conformational change of BSA from a compact to an extended structure. For the HA precoated with BSA, both C4S and heparin adsorption decrease above a certain solution concentration. A possible explanation is that precoated BSA masks binding sites for the C4S/heparin. The percentage of BSA desorbed from the precoated HA in the presence of C4S and heparin is < 10% and < 30% respectively, indicating that BSA is strongly bound to the HA surface.

Adsorption↗

PubMed1997

Adsorption of chondroitin-4-sulphate and heparin onto titanium: effect of bovine serum albumin.

The adsorption of chondroitin-4-sulphate (C4S) and heparin onto titanium has been studied in the absence and presence of bovine serum albumin (BSA). Isotherm data (0.02 M calcium acetate, pH 6.8) have shown that BSA in solution and BSA-coated titanium result in decreased adsorption for both C4S and heparin. For the BSA in solution data, C4S/heparin and BSA may compete for the same sites on the titanium surface via calcium ions, or alternatively in the case of heparin, complexes of heparin and BSA form in solution, leading to less binding due to steric effects. Evidence of an interaction between heparin and BSA in solution has been shown in this study, there being negligible interaction between C4S and BSA. BSA adsorption from solution investigated in the presence of C4S/heparin decreases with increasing C4S/heparin solution concentration. This may be due to a glycosaminoglycan (GAG) induced conformational change of BSA from a compact to an extended structure. The decreased adsorption onto BSA-coated titanium may be due to masking of the GAG binding sites, this effect being greater for C4S. Desorption of BSA from the pre-coated titanium in the presence of C4S and heparin is <10% and <30% respectively, indicating that BSA is strongly bound to the titanium surface.

Adsorption↗

PubMed1997

A biochemical and immuno-electron microscopical analysis of chondroitin sulphate-rich proteoglycans in human alveolar bone.

This study used biochemical and immunohistochemical methods to characterize the chondroitin sulphate-rich proteoglycans from human alveolar bone obtained from an oral source. Proteoglycans were extracted from bone by a sequential 4 M guanidine HCl extraction process, and purified by DEAE-ion exchange chromatography. SDS-PAGE and Western blot analysis, using CS-56 monoclonal antibody, demonstrated one major proteoglycan species with a core protein of 58 kDa, glycosaminoglycan chains of 45-66 kDa and a mean molecular weight of 205 kDa. This work confirmed the biochemistry of chondroitin sulphate-rich proteoglycans from a novel source of adult human alveolar bone, and pointed towards a proteoglycan with a high glutamate, glycine, aspartate, alanine, serine and leucine content. Sections of alveolar bone were embedded in LR White resin, labelled with CS-56 antibody and examined with the light and electron microscopes. At the light microscope level, labelling was restricted to the osteocyte lacunae and canaliculi. Ultrastructural observations showed that the labelling was localized to fine filamentous material in the walls of the osteocytes and canaliculi. Sparse labelling was associated with the collagen fibres immediately subjacent to the lamina limitans, but no labelling of the mineralized matrix was observed. These findings also indicated subtle differences in the distribution of chondroitin sulphate compared with previously reported work, which may indicate species or age differences in the samples used in this study. Ultrastructural analysis confirmed and extended observations of glycosaminoglycan localization at the osteocyte cell membrane of mature human alveolar bone.

Adult↗