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  • 1
    Electronic Resource
    Electronic Resource
    Effects of metallic debris on adult bovine articular chondrocyte metabolism in vitro (1994)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Biomaterials 5 (1994), S. 109-115 
    Details
    ISSN: 1045-4861
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine , Technology
    Notes: The purpose of this study was to examine the effects of particles, derived from metals commonly used in joint prostheses, on chondrocyte proliferation, metabolism, and morphology in vitro. Chondrocyte viability was influenced by the type and concentration of metal particle added. Cobalt was toxic to chondrocytes at all particle concentrations (0.83-0.000083%, v/v), whereas the chromium, titanium and titanium-aluminum particles only effected chondrocyte viability at high concentrations. The metabolic response of chondrocytes to particulate debris as assessed by caseinase, collagenase, and hexosaminidase activities were variable at low concentrations but were always reduced at high concentrations (0.83% v/v). Prostaglandin E2 levels in the medium showed a steady increase when particle load increased, except in the medium of chondrocytes exposed to titanium-aluminum. Scanning electron microscopy of chondrocytes exposed to titanium showed ruffled cell borders and frequent membrane blebbings. This was in contrast to chondrocytes exposed to cobalt, where the crenated appearance indicated cell death, and titanium-aluminum, where the cells appeared quiescent. These findings show that metal particles alter chondrocyte viability and metabolism and suggest that particulate debris may influence the integrity and stability of articular cartilage following hemiarthroplasty. © 1994 John Wiley & Sons, Inc.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jab.770050203
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  • 2
    Electronic Resource
    Electronic Resource
    Effects of serum protein opsonization on cytokine release by titanium-alloy particles (1998)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Biomedical Materials Research 41 (1998), S. 371-376 
    Details
    ISSN: 0021-9304
    Keywords: titanium alloy ; particulate debris ; total joint arthroplasty ; monocytes/macrophages ; cytokines ; SDS-PAGE ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine , Technology
    Notes: This study tested whether macrophages respond differently to retrieved titanium-alloy particles than they do to machined titanium-alloy particles and assessed whether pretreatment of machined titanium-alloy particles with human serum would influence macrophage activation and cytokine release in vitro. Human monocyte/macrophages were isolated from normal healthy donors and exposed to increasing concentrations of machined and retrieved titanium-alloy particles. The profile of cytokine release was determined by commercially available ELISA kits. Machined titanium-alloy particles were opsonized with human serum and added to macrophage cultures. Serum protein binding was confirmed by SDS-PAGE analysis. The results showed that machined titanium-alloy particles and retrieved titanium-alloy particles stimulate a similar level of cytokine release when tested at comparable concentrations. Opsonization of the machined particles with human serum increased the macrophage release of cytokines in the first 12 h after exposure compared to nonopsonized particles. At 24 h, the opsonized particles stimulated significantly higher levels of cytokine release, but only at the greatest particle concentrations. This study demonstrates that machined titanium alloy induces a metabolic response in macrophages similar to that of titanium-alloy particles retrieved from failed total hip arthroplasty. In addition, these data show that serum protein binding to orthopedic biomaterial debris alters the macrophage reaction to the particles. © 1998 John Wiley & Sons, Inc. J Biomed Mater Res, 41, 371-376, 1998.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Effects of polyethylene particles on tissue surrounding knee arthroplasties in rabbits (1998)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Biomedical Materials Research 43 (1998), S. 123-130 
    Details
    ISSN: 0021-9304
    Keywords: total joint replacement ; animal model ; particles ; polyethylene ; interface ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine , Technology
    Notes: Clinical studies suggest a role for polyethylene (PE) wear debris in the pathogenesis of osteolysis and loosening of total joint replacements. In this study, submicron particles of ultrahigh molecular weight PE (UHMWPE) were placed around pressfit tibial hemiarthroplasties in rabbits to determine the biological reaction. After 6 months the periprosthetic tissue was harvested and characterized biochemically by measuring the extracellular matrix macromolecules, collagen, and glycosaminoglycan (GAG) and quantifying the expression of inflammatory/osteolytic mediators [prostaglandin E2 (PGE2), hexosaminidase, transforming growth factor β (TGFβ), and interleukins-6 and -1 (IL-6, IL-1)]. Particle exposure resulted in a decrease in levels of total extracellular matrix molecules including a 53% decrease in total GAG (p 〈 0.05) and a 74% decrease in total collagen (p 〈 0.005). Collagen content remained significantly decreased when normalized for cellularity (DNA content). Total TGFβ release exhibited a downward trend (p = 0.06) in the particle exposed group. Hexosaminidase and PGE2 levels did not show a difference between groups; however, when normalized for cellularity, PGE2 values exhibited an upward trend in the particle exposed group (p = 0.1). IL-6 was undetected by bioassay and ELISA. Previous studies emphasized that PE debris enhances the degradation of bone. The data from this in vivo model suggest that submicron UHMWPE particles may also act to inhibit biosynthetic pathways of bone and mesenchymal tissue. Decreased levels of collagen, GAG, and TGFβ expression may indicate suppression of bone formation, possibly through a downregulation of osteoblast activity. © 1998 John Wiley & Sons, Inc. J Biomed Mater Res (Appl Biomater) 43: 123-130, 1998
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Effect of size, concentration, surface area, and volume of polymethylmethacrylate particles on human macrophages in vitro (1996)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Biomedical Materials Research 30 (1996), S. 463-473 
    Details
    ISSN: 0021-9304
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine , Technology
    Notes: This study investigated effects of different sizes, concentrations, volumes, and surface areas of polymethylmethacrylate (PMMA) particles on human macrophages. Adherent peripheral blood monocytes isolated from five healthy individuals were exposed for 48 h to phagocytosable (0.325 μm and 5.5 μm) and nonphagocytosable (200 μm) spherical particles. Each particle size was tested over a range of concentrations (104-1011 particles per milliliter [0.325 μm], 102-107 particles per milliliter [5.5 μm], 101-104 particles per milliliter [200 μm]) to provide overlap in number, volume, and surface area. Primary human monocyte/macrophages were cultured in macrophage serum-free medium and 5% fetal calf serum. Macrophage viability was assessed by 3H-thymidine uptake and activation was quantified by release of interleukin-1β, interleukin-6, tumor necrosis factor-α, prostaglandin E2 (PGE2), and the lysosomal enzyme hexosaminidase. Medium alone served as a negative control; lipopolysaccharide (10 μg/mL) was also tested. PMMA particles were not toxic to human macrophages at any concentration tested. The smallest phagocytosable particles (0.325 μm) stimulated the release of interleukin-1β, interleukin-6, prostaglandin E2, and hexosaminidase at concentrations of 1010-1011 particles/mL. The release of cytokines, PGE2, and hexosaminidase depended on the size, concentration, surface area, and volume of the phagocytosable particles. This study demonstrates that PMMA particle load Mi.e., the concentration of phagocytosable particles per tissue volume, characterized by size, surface area, and volume, rather than simply particle number - determines the degree of macrophage activation. © 1996 John Wiley & Sons, Inc.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Comparison of cartilage destruction between infectious and adjuvant arthritis (1983)
    Hoboken, NJ [u.a.] : Wiley-Blackwell
    Journal of Orthopaedic Research 1 (1983), S. 136-143 
    Details
    ISSN: 0736-0266
    Keywords: Glycosaminoglycan ; Collagen ; Proteoglycan ; Infectious arthritis ; Adjuvant arthritis ; Articular cartilage ; Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The timing and molecular profile of cartilage destruction in Escherichia coli and Staphylococcus aureus infectious arthritis and killed Mycobacterium butyricum adjuvant arthritis are presented. Infectious arthritis was studied for 3 weeks; cartilage samples were analyzed at 2, 10, and 21 days. At 48 h postinfection, glycosaminoglycan content was reduced by 20% (p 〈 0.05) in E. coli infected knees and by 42% (p 〈 0.05) in tibial plateau cartilage of S. aureus infected knees. By the 3rd week of infection, glycosaminoglycan losses amounted to as much as 73% (p 〈 0.005). In comparison, collagen losses were not significant prior to the 3rd week of infection, at which time 42% (p 〈 0.05) was lost. Adjuvant arthritic tibial plateau cartilage was examined at 1, 3 and 12 weeks. Glycosaminoglycans decreased by 42% the 1st week, plateauing at 62% by the 3rd and 12th weeks. Collagen degradation began at 3 weeks (28% loss, p 〈 0.10) and by the 12th week was reduced by 49% (p 〈 0.005). Analysis of the individual species of glycosaminoglycan showed a parallel loss of chondroitin sulfate and keratan sulfate. Fractionation of glycosaminoglycans with respect to size produced no evidence of shortened chains in cartilage from infected joints. Hyaluronic acid losses were greatest when collagen was significantly decreased. The pattern by which chondroitin and keratan sulfates are lost demonstrates that a prominent feature of infectious and noninfectious inflammatory arthritis is a rapid loss of proteoglycan subunits that precedes collagen loss.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jor.1100010204
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  • 6
    Electronic Resource
    Electronic Resource
    Growth hormone stimulates insulin-like growth factor I actions on adult articular chondrocytes (1989)
    Hoboken, NJ [u.a.] : Wiley-Blackwell
    Journal of Orthopaedic Research 7 (1989), S. 198-207 
    Details
    ISSN: 0736-0266
    Keywords: Insulin-like growth factor I (somatomedin-C) ; Articular chondrocytes ; Proteoglycan ; Keratan sulfate ; Growth hormone ; Glycosaminoglycan ; Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: We report effects of adding insulin-like growth factor I (IGF-I) and methionyl human growth hormone (GH), alone or in combination, to adult bovine articular chondrocytes plated at high density. Purified human and synthetic IGF-I stimulated chondrocyte DNA and proteoglycan synthesis. GH had no effect on either process. However, GH added in combination with IGF-I increased proteoglycan, cell-associated proteoglycan, and keratan sulfate synthesis over levels observed with IGF-I alone. IGF-I and GH did not alter the hydrodynamic size of proteoglycans or synthesis of collagen. Our results show that GH and IGF-I act together to stimulate adult chondrocyte extracellular matrix synthesis.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jor.1100070207
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  • 7
    Electronic Resource
    Electronic Resource
    Biochemistry of fusion mass consolidation in the sheep spine (1988)
    Hoboken, NJ [u.a.] : Wiley-Blackwell
    Journal of Orthopaedic Research 6 (1988), S. 138-144 
    Details
    ISSN: 0736-0266
    Keywords: Sheep spine ; Spinal fusion ; Glycosaminoglycan ; Collagen ; Mineral ; Bone formation ; Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: We report here the biochemistry of fusion mass consolidation in sheep spines during a 1-year period following autogenous cortical-cancellous bone grafting and stabilization with Harrington distraction rods. Biochemical analysis of vertebral fusion mass included determination of wet weight and dry weight and quantification of glycosaminoglycan, collagen, calcium, and phosphate following extraction with neutral EDTA and proteolytic hydrolysis with papain. Our results showed that at 1 week after surgery, the fusion mass consisted of original cortical and cancellous bone graft material. The cortical bone graft was partially resistant to EDTA-papain treatment, resulting in a residue containing hydroxyproline and mineral. At 12 weeks after surgery, the fusion mass had become a homogeneous material, which, like cancellous bone graft, was completely susceptible to treatment by EDTA-papain. Collagen content of consolidating fusion mass was highest at 16 weeks after surgery when normalized to dry weight; glycosaminoglycan content was highest within 6 weeks after surgery. Mineral content was lowest at the 6-week stage but by 12 weeks after surgery, it was comparable with original bone grafting material. At 24 and 52 weeks after surgery, fusion mass consolidation was characterized by an increase in the proportion of organic and mineral components resistant to EDTA-papain. The appearance of the EDTA-papain-resistant material in the fusion mass coincided with formation of lamellar bone and successful consolidation.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jor.1100060118
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  • 8
    Electronic Resource
    Electronic Resource
    Keratan sulfate content and articular cartilage maturation during postnatal rabbit growth (1984)
    Hoboken, NJ [u.a.] : Wiley-Blackwell
    Journal of Orthopaedic Research 2 (1984), S. 143-150 
    Details
    ISSN: 0736-0266
    Keywords: Keratan sulfate ; Cartilage maturation ; Glycosaminoglycan ; Proteoglycan ; Rabbit ; Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: This article describes the macromolecular changes in keratan sulfate and proteoglycan that occur in rabbit articular cartilage during postnatal development. Articular cartilage glycosaminoglycan from femoral condyles and the tibial plateaus of rabbits at 8, 12, 18, and 26 weeks and 2 years of age were extracted, fractionated, and quantified. The predominant glycosaminoglycan present in articular cartilage at 8 weeks was chondroitin sulfate. During subsequent maturation the relative proportions of keratan sulfate and chondroitin sulfate varied inversely. The greatest increase in the amount of keratan sulfate present in cartilage was observed between 12 and 26 weeks of age. Hyaluronic acid content was measurable at 12 weeks; afterward the amount remained relatively constant with age. Proteoglycans, extracted from 6-, 12-, and 22-week-old rabbit femoral and tibial cartilage in the presence of protease inhibitors, were analyzed on columns of Sepharose CL-2B. Cartilage proteoglycans decreased in hydrodynamic size between 12 and 22 weeks, corresponding to the period of maximal change in content of keratan and chondroitin sulfate.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jor.1100020205
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  • 9
    Electronic Resource
    Electronic Resource
    Biochemistry and antigenicity of osteoarthritic and rheumatoid cartilage (1986)
    Hoboken, NJ [u.a.] : Wiley-Blackwell
    Journal of Orthopaedic Research 4 (1986), S. 255-262 
    Details
    ISSN: 0736-0266
    Keywords: Rheumatoid arthritis ; Articular cartilage ; Proteoglycan ; Type II collagen ; Immunoglobulins ; Lympho-cytes ; Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The purpose of this study was to test whether cartilage serves as the source or repository of antigenic components active in the stimulation of inflammation in rheumatoid arthritis through an analysis of peripheral blood lymphocyte proliferation. Articular cartilage samples were obtained from patients with osteoarthritis, rheumatoid arthritis, and ankylosing spondylitis undergoing joint replacement surgery. Each sample was homogenized and characterized biochemically with respect to the content of proteoglycan, collagen, and immunoglobulin. Proteoglycan content of rheumatoid cartilage was reduced by 71% when compared to osteoarthritic cartilage; the proteoglycan content of ankylosing spondylitis cartilage was reduced by 40% when compared to osteoarthritic cartilage. Immunoglobulins were detectable in all cartilage samples when analyzed by ELISA or endoplate titration. Lymphocyte proliferation, quantified by uptake of 3H-thymidine, was unaltered by addition of cartilage fragments, low (saline) and high salt extracts (2.0 M CaCl2), or cartilage residues. Both autologous and heterologous lymphocytes were tested against the cartilage samples with no difference in reactivity. Purified bovine articular proteoglycans and Type II collagen were also inactive. Although tetanus toxoid and phytohemaglutinin were effective stimulants of proliferation, lymphocytes from arthritis patients were suppressed relative to those of normal individuals. Analysis of arthritic articular cartilage by these techniques failed to demonstrate the presence of antigen(s) stimulating proliferation of peripheral blood lymphocytes.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jor.1100040301
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  • 10
    Electronic Resource
    Electronic Resource
    Quantitation of glycocalyx production in coagulase-negative Staphylococcus (1988)
    Hoboken, NJ [u.a.] : Wiley-Blackwell
    Journal of Orthopaedic Research 6 (1988), S. 666-670 
    Details
    ISSN: 0736-0266
    Keywords: Bacterial glycocalyx ; Biofilm ; Staphylococcus epidermidis ; Toluidine blue ; Spectrophotometric technique ; Bacterial slime ; Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The purpose of this study was to develop sensitive and accurate methods of quantitating bacterial glycocalyx. Coagulase-negative staphylococci were cultured in trypticase soy broth. Quantitation of slime production was evaluated using various methods of fixation and staining. The amount of dye associated with bacterial slime was assessed spectrophotometrically following solubilization of the dye-biofilm complex by 0.2 M NaOH at 85°C for 1 h. Carnoy's solution was optimal for fixation of the slime, and toluidine blue staining was most reproducible. Fifteen strains of Staphylococcus epidermidis showed a gradation in biofilm production ranging from high, medium, to low that was strain stable. Irrespective of the technique used, high, medium, and low producers of bacterial slime remained in the same category and always showed significantly different optical density reading (p 〈 0.05). In our experiments, solubilization of a toluidine blue-bacterial biofilm complex was a direct, simple, and efficient method for reproducibly quantitating glycocalyx. This method provides a useful means of rapid quantitation of biofilm production to assess its role in the infection process and in the response to antibiotic therapy.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jor.1100060507
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