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Joshua J Jacobs - One of the best experts on this subject based on the ideXlab platform.

  • intergranular pitting corrosion of cocrmo biomedical Implant Alloy
    Journal of Biomedical Materials Research Part B, 2014
    Co-Authors: Pooja Panigrahi, Joshua J Jacobs, Yifeng Liao, Mathew T Mathew, Alfons Fischer, Markus A Wimmer, Laurence Marks
    Abstract:

    : CoCrMo samples of varying microstructure and carbon content were electrochemically corroded in vitro and examined by scanning electron microscopy and electron backscatter diffraction techniques. The rate of corrosion was minimized (80% reduction from icorr = 1396 nA/cm(2) to icorr = 276 nA/cm(2) ) in high-carbon CoCrMo Alloys which displayed a coarser grain structure and partially dissolved second phases, achieved by solution annealing at higher temperatures for longer periods of time. The mechanism of degradation was intergranular pitting corrosion, localized at phase boundaries and grain boundaries of high energy (high-angle and low lattice coincidence, Σ11 or higher); grain boundaries of lower energy did not appear to corrode. This suggests the possibility of grain boundary engineering to improve the performance of metal Implant devices. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 102B: 850-859, 2014.

  • interfacial kinetics of titanium and cobalt based Implant Alloys in human serum metal release and biofilm formation
    Journal of Biomedical Materials Research Part A, 2003
    Co-Authors: Nadim J Hallab, Anastasia K Skipor, Joshua J Jacobs
    Abstract:

    The biocompatibility of metallic Implant surfaces is governed in large part by the interfacial kinetics associated with metal release and protein binding. The kinetics of metal release from, and protein binding to, cobalt- and titanium-based Implant Alloys in human serum were investigated by (1) measuring the temporal release of Cr and Ti into serum from Co-Cr-Mo (ASTM F-75) and Ti Implant Alloys (Ti-6Al-4V: ASTM F136, and commercially pure Ti, cpTi: ASTM F67), respectively; (2) examining the composition of human serum proteins adsorbed onto the surfaces of Co- and Ti-based Implant Alloys; and (3) identifying the serum proteins associated with the binding of soluble Cr and Ti degradation products. Analysis of metal dissolution kinetics found that Cr was released from Co-based Implant Alloy at an order of magnitude higher than Ti was released from Ti-based Implant Alloys. Serum became saturated with soluble CR and Ti at levels as high as 3,250 ng/mL Ti from cpTi; 3,750 ng/mL Ti from Ti-6Al-4V; and 35,400 ng/mL Cr from Co-Cr-Mo degradation. The observation that human serum binds more released metal from Co-based Alloy dissolution was consistent with the observed differences in biofilm composition between the two Alloys, where additional serum protein(s) of approximately ≈140 (kDa) molecular weight were detected on Co-based Implant Alloy surfaces. However, both Cr and Ti released from Co- and Ti-based Alloys exhibited a bimodal binding pattern to both low molecular weight serum protein(s) (<32 kDa), and to higher molecular weight protein(s) in the 180–250 kDa range. Identification of metal Alloy–dependent biofilm compositions and dissolution products provides the basis for understanding the bioavailability and bioreactivity of these Implant Alloys and their degradation products. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 65A: 311–318, 2003

  • orthopaedic Implant related metal toxicity in terms of human lymphocyte reactivity to metal protein complexes produced from cobalt base and titanium base Implant Alloy degradation
    Molecular and Cellular Biochemistry, 2001
    Co-Authors: Nadim J Hallab, Csaba Vermes, Katalin Mikecz, Anastasia K Skipor, Joshua J Jacobs
    Abstract:

    Metal toxicity from sources such as orthopaedic Implants was investigated in terms of immune system hyper-reactivity to metal Implant Alloy degradation products. Lymphocyte response to serum protein complexed with metal from Implant Alloy degradation was investigated in this in vitro study using primary human lymphocytes from healthy volunteers (n = 10). Cobalt chromium molybdenum Alloy (Co‐Cr‐Mo, ASTM F‐75) and titanium Alloy (Ti‐6Al‐4V, ASTM F‐136) beads (70 μm) were incubated in agitated human serum at 37 degrees Celsius to simulate naturally occurring metal Implant Alloy degradation processes. Particulate free serum samples, which were incubated with metal, were then separated into molecular weight based fractions. The amounts of soluble Cr and Ti within each serum fraction were measured and correlated with lymphocyte proliferation response to the individual serum fractions. Lymphocytes from each subject were cultured with 11 autologous molecular weight based serum fractions either with or without added metal. Two molecular weight ranges of human serum proteins were associated with the binding of Cr and Ti from Co‐Cr‐Mo and Ti Implant Alloy degradation (at < 30 and 180–330 kDa). High molecular weight serum proteins (≈ 180 kDa) demonstrated greater lymphocyte reactivity when complexed with metal released from Co‐Cr‐Mo Alloy and Ti Alloy than with low (5–30 kDa) and midrange (30–77 kDa) serum proteins. When the amount of lymphocyte stimulation was normalized to both the moles of metal and the moles of protein within each fraction (Metal‐Protein Complex Reactivity Index, MPCRI), Cr from Co‐Cr‐Mo Alloy degradation demonstrated approximately 10 fold greater reactivity than Ti in the higher molecular weight serum proteins (≈ 180–250 kDa). This in vitro study demonstrated a lymphocyte proliferative response to both Co‐Cr‐Mo and Ti Alloy metalloprotein degradation products. This response was greatest when the metals were complexed with high molecular weight proteins, and with metal‐protein complexes formed from Co‐Cr‐Mo Alloy degradation.

  • differential lymphocyte reactivity to serum derived metal protein complexes produced from cobalt based and titanium based Implant Alloy degradation
    Journal of Biomedical Materials Research, 2001
    Co-Authors: Nadim J Hallab, Csaba Vermes, Katalin Mikecz, Anastasia K Skipor, Joshua J Jacobs
    Abstract:

    The lymphocyte response to serum protein complexed with metal from Implant Alloy degradation was investigated in this in vitro study using primary human lymphocytes from healthy volunteers (n = 10). Cobalt chromium molybdenum Alloy (Co-Cr-Mo, ASTM F-75) and titanium Alloy (Ti-6Al-4V, ASTM F-136) beads (70 μm) were incubated in agitated human serum at 37°C to simulate naturally occurring metal Implant Alloy degradation processes. Particulate free serum samples that had been incubated with metal were then separated into molecular weight based fractions. The amounts of soluble Cr and Ti within each serum fraction were measured and correlated with lymphocyte proliferation response to the individual serum fractions. Lymphocytes from each subject were cultured with 11 autologous molecular weight based serum fractions either with or without added metal. Two molecular weight ranges of human serum proteins were associated with the binding of Cr and Ti from Co-Cr-Mo and Ti Implant Alloy degradation (at <30 and 180–250 kDa). High molecular weight serum proteins (∼180 kDa) demonstrated greater lymphocyte reactivity when complexed with Cr Alloy and Ti Alloy than low (5–30 kDa) and midrange (30–77 kDa) serum proteins. When the amount of lymphocyte stimulation was normalized to both the moles of metal and the moles of protein within each fraction (metal–protein complex reactivity index), Cr from Co-Cr-Mo Alloy degradation demonstrated approximately 10-fold greater reactivity than Ti in the higher molecular weight serum proteins (∼180 kDa). This in vitro study demonstrated a lymphocyte proliferative response to both Co-Cr-Mo and Ti Alloy metalloprotein degradation products. This response was greatest when the metals were complexed with high molecular weight proteins, and with metal–protein complexes formed from Co-Cr-Mo Alloy degradation. © 2001 John Wiley & Sons, Inc. J Biomed Mater Res 56: 427–436, 2001

  • differential lymphocyte reactivity to serum derived metal protein complexes produced from cobalt based and titanium based Implant Alloy degradation
    Journal of Biomedical Materials Research, 2001
    Co-Authors: Nadim J Hallab, Csaba Vermes, Katalin Mikecz, Anastasia K Skipor, Joshua J Jacobs
    Abstract:

    The lymphocyte response to serum protein complexed with metal from Implant Alloy degradation was investigated in this in vitro study using primary human lymphocytes from healthy volunteers (n = 10). Cobalt chromium molybdenum Alloy (Co-Cr-Mo, ASTM F-75) and titanium Alloy (Ti-6Al-4V, ASTM F-136) beads (70 microm) were incubated in agitated human serum at 37 degrees C to simulate naturally occurring metal Implant Alloy degradation processes. Particulate free serum samples that had been incubated with metal were then separated into molecular weight based fractions. The amounts of soluble Cr and Ti within each serum fraction were measured and correlated with lymphocyte proliferation response to the individual serum fractions. Lymphocytes from each subject were cultured with 11 autologous molecular weight based serum fractions either with or without added metal. Two molecular weight ranges of human serum proteins were associated with the binding of Cr and Ti from Co-Cr-Mo and Ti Implant Alloy degradation (at <30 and 180-250 kDa). High molecular weight serum proteins ( approximately 180 kDa) demonstrated greater lymphocyte reactivity when complexed with Cr Alloy and Ti Alloy than low (5-30 kDa) and midrange (30-77 kDa) serum proteins. When the amount of lymphocyte stimulation was normalized to both the moles of metal and the moles of protein within each fraction (metal-protein complex reactivity index), Cr from Co-Cr-Mo Alloy degradation demonstrated approximately 10-fold greater reactivity than Ti in the higher molecular weight serum proteins ( approximately 180 kDa). This in vitro study demonstrated a lymphocyte proliferative response to both Co-Cr-Mo and Ti Alloy metalloprotein degradation products. This response was greatest when the metals were complexed with high molecular weight proteins, and with metal-protein complexes formed from Co-Cr-Mo Alloy degradation.

Nadim J Hallab - One of the best experts on this subject based on the ideXlab platform.

  • interfacial kinetics of titanium and cobalt based Implant Alloys in human serum metal release and biofilm formation
    Journal of Biomedical Materials Research Part A, 2003
    Co-Authors: Nadim J Hallab, Anastasia K Skipor, Joshua J Jacobs
    Abstract:

    The biocompatibility of metallic Implant surfaces is governed in large part by the interfacial kinetics associated with metal release and protein binding. The kinetics of metal release from, and protein binding to, cobalt- and titanium-based Implant Alloys in human serum were investigated by (1) measuring the temporal release of Cr and Ti into serum from Co-Cr-Mo (ASTM F-75) and Ti Implant Alloys (Ti-6Al-4V: ASTM F136, and commercially pure Ti, cpTi: ASTM F67), respectively; (2) examining the composition of human serum proteins adsorbed onto the surfaces of Co- and Ti-based Implant Alloys; and (3) identifying the serum proteins associated with the binding of soluble Cr and Ti degradation products. Analysis of metal dissolution kinetics found that Cr was released from Co-based Implant Alloy at an order of magnitude higher than Ti was released from Ti-based Implant Alloys. Serum became saturated with soluble CR and Ti at levels as high as 3,250 ng/mL Ti from cpTi; 3,750 ng/mL Ti from Ti-6Al-4V; and 35,400 ng/mL Cr from Co-Cr-Mo degradation. The observation that human serum binds more released metal from Co-based Alloy dissolution was consistent with the observed differences in biofilm composition between the two Alloys, where additional serum protein(s) of approximately ≈140 (kDa) molecular weight were detected on Co-based Implant Alloy surfaces. However, both Cr and Ti released from Co- and Ti-based Alloys exhibited a bimodal binding pattern to both low molecular weight serum protein(s) (<32 kDa), and to higher molecular weight protein(s) in the 180–250 kDa range. Identification of metal Alloy–dependent biofilm compositions and dissolution products provides the basis for understanding the bioavailability and bioreactivity of these Implant Alloys and their degradation products. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 65A: 311–318, 2003

  • orthopaedic Implant related metal toxicity in terms of human lymphocyte reactivity to metal protein complexes produced from cobalt base and titanium base Implant Alloy degradation
    Molecular and Cellular Biochemistry, 2001
    Co-Authors: Nadim J Hallab, Csaba Vermes, Katalin Mikecz, Anastasia K Skipor, Joshua J Jacobs
    Abstract:

    Metal toxicity from sources such as orthopaedic Implants was investigated in terms of immune system hyper-reactivity to metal Implant Alloy degradation products. Lymphocyte response to serum protein complexed with metal from Implant Alloy degradation was investigated in this in vitro study using primary human lymphocytes from healthy volunteers (n = 10). Cobalt chromium molybdenum Alloy (Co‐Cr‐Mo, ASTM F‐75) and titanium Alloy (Ti‐6Al‐4V, ASTM F‐136) beads (70 μm) were incubated in agitated human serum at 37 degrees Celsius to simulate naturally occurring metal Implant Alloy degradation processes. Particulate free serum samples, which were incubated with metal, were then separated into molecular weight based fractions. The amounts of soluble Cr and Ti within each serum fraction were measured and correlated with lymphocyte proliferation response to the individual serum fractions. Lymphocytes from each subject were cultured with 11 autologous molecular weight based serum fractions either with or without added metal. Two molecular weight ranges of human serum proteins were associated with the binding of Cr and Ti from Co‐Cr‐Mo and Ti Implant Alloy degradation (at < 30 and 180–330 kDa). High molecular weight serum proteins (≈ 180 kDa) demonstrated greater lymphocyte reactivity when complexed with metal released from Co‐Cr‐Mo Alloy and Ti Alloy than with low (5–30 kDa) and midrange (30–77 kDa) serum proteins. When the amount of lymphocyte stimulation was normalized to both the moles of metal and the moles of protein within each fraction (Metal‐Protein Complex Reactivity Index, MPCRI), Cr from Co‐Cr‐Mo Alloy degradation demonstrated approximately 10 fold greater reactivity than Ti in the higher molecular weight serum proteins (≈ 180–250 kDa). This in vitro study demonstrated a lymphocyte proliferative response to both Co‐Cr‐Mo and Ti Alloy metalloprotein degradation products. This response was greatest when the metals were complexed with high molecular weight proteins, and with metal‐protein complexes formed from Co‐Cr‐Mo Alloy degradation.

  • differential lymphocyte reactivity to serum derived metal protein complexes produced from cobalt based and titanium based Implant Alloy degradation
    Journal of Biomedical Materials Research, 2001
    Co-Authors: Nadim J Hallab, Csaba Vermes, Katalin Mikecz, Anastasia K Skipor, Joshua J Jacobs
    Abstract:

    The lymphocyte response to serum protein complexed with metal from Implant Alloy degradation was investigated in this in vitro study using primary human lymphocytes from healthy volunteers (n = 10). Cobalt chromium molybdenum Alloy (Co-Cr-Mo, ASTM F-75) and titanium Alloy (Ti-6Al-4V, ASTM F-136) beads (70 μm) were incubated in agitated human serum at 37°C to simulate naturally occurring metal Implant Alloy degradation processes. Particulate free serum samples that had been incubated with metal were then separated into molecular weight based fractions. The amounts of soluble Cr and Ti within each serum fraction were measured and correlated with lymphocyte proliferation response to the individual serum fractions. Lymphocytes from each subject were cultured with 11 autologous molecular weight based serum fractions either with or without added metal. Two molecular weight ranges of human serum proteins were associated with the binding of Cr and Ti from Co-Cr-Mo and Ti Implant Alloy degradation (at <30 and 180–250 kDa). High molecular weight serum proteins (∼180 kDa) demonstrated greater lymphocyte reactivity when complexed with Cr Alloy and Ti Alloy than low (5–30 kDa) and midrange (30–77 kDa) serum proteins. When the amount of lymphocyte stimulation was normalized to both the moles of metal and the moles of protein within each fraction (metal–protein complex reactivity index), Cr from Co-Cr-Mo Alloy degradation demonstrated approximately 10-fold greater reactivity than Ti in the higher molecular weight serum proteins (∼180 kDa). This in vitro study demonstrated a lymphocyte proliferative response to both Co-Cr-Mo and Ti Alloy metalloprotein degradation products. This response was greatest when the metals were complexed with high molecular weight proteins, and with metal–protein complexes formed from Co-Cr-Mo Alloy degradation. © 2001 John Wiley & Sons, Inc. J Biomed Mater Res 56: 427–436, 2001

  • differential lymphocyte reactivity to serum derived metal protein complexes produced from cobalt based and titanium based Implant Alloy degradation
    Journal of Biomedical Materials Research, 2001
    Co-Authors: Nadim J Hallab, Csaba Vermes, Katalin Mikecz, Anastasia K Skipor, Joshua J Jacobs
    Abstract:

    The lymphocyte response to serum protein complexed with metal from Implant Alloy degradation was investigated in this in vitro study using primary human lymphocytes from healthy volunteers (n = 10). Cobalt chromium molybdenum Alloy (Co-Cr-Mo, ASTM F-75) and titanium Alloy (Ti-6Al-4V, ASTM F-136) beads (70 microm) were incubated in agitated human serum at 37 degrees C to simulate naturally occurring metal Implant Alloy degradation processes. Particulate free serum samples that had been incubated with metal were then separated into molecular weight based fractions. The amounts of soluble Cr and Ti within each serum fraction were measured and correlated with lymphocyte proliferation response to the individual serum fractions. Lymphocytes from each subject were cultured with 11 autologous molecular weight based serum fractions either with or without added metal. Two molecular weight ranges of human serum proteins were associated with the binding of Cr and Ti from Co-Cr-Mo and Ti Implant Alloy degradation (at <30 and 180-250 kDa). High molecular weight serum proteins ( approximately 180 kDa) demonstrated greater lymphocyte reactivity when complexed with Cr Alloy and Ti Alloy than low (5-30 kDa) and midrange (30-77 kDa) serum proteins. When the amount of lymphocyte stimulation was normalized to both the moles of metal and the moles of protein within each fraction (metal-protein complex reactivity index), Cr from Co-Cr-Mo Alloy degradation demonstrated approximately 10-fold greater reactivity than Ti in the higher molecular weight serum proteins ( approximately 180 kDa). This in vitro study demonstrated a lymphocyte proliferative response to both Co-Cr-Mo and Ti Alloy metalloprotein degradation products. This response was greatest when the metals were complexed with high molecular weight proteins, and with metal-protein complexes formed from Co-Cr-Mo Alloy degradation.

  • evaluation of metallic and polymeric biomaterial surface energy and surface roughness characteristics for directed cell adhesion
    Tissue Engineering, 2001
    Co-Authors: Nadim J Hallab, Kirk J Bundy, Kim C Oconnor, Randy L Moses, Joshua J Jacobs
    Abstract:

    Directed cell adhesion remains an important goal of Implant and tissue engineering technology. In this study, surface energy and surface roughness were investigated to ascertain which of these properties show more overall influence on biomaterial–cell adhesion and colonization. Jet impingement was used to quantify cellular adhesion strength. Cellular proliferation and extracellular matrix secretion were used to characterize colonization of 3T3MC fibroblasts on: HS25 (a cobalt based Implant Alloy, ASTM F75), 316L stainless steel, Ti-6Al4V (a titanium Implant Alloy), commercially pure tantalum (Ta), polytetrafluoroethylene (PTFE), silicone rubber (SR), and high-density polyethylene (HDPE). The metals exhibited a nearly five-fold greater adhesion strength than the polymeric materials tested. Generally, surface energy was proportional to cellular adhesion strength. Only polymeric materials demonstrated significant increased adhesion strength associated with increased surface roughness. Cellular adhesion on me...

Anastasia K Skipor - One of the best experts on this subject based on the ideXlab platform.

  • interfacial kinetics of titanium and cobalt based Implant Alloys in human serum metal release and biofilm formation
    Journal of Biomedical Materials Research Part A, 2003
    Co-Authors: Nadim J Hallab, Anastasia K Skipor, Joshua J Jacobs
    Abstract:

    The biocompatibility of metallic Implant surfaces is governed in large part by the interfacial kinetics associated with metal release and protein binding. The kinetics of metal release from, and protein binding to, cobalt- and titanium-based Implant Alloys in human serum were investigated by (1) measuring the temporal release of Cr and Ti into serum from Co-Cr-Mo (ASTM F-75) and Ti Implant Alloys (Ti-6Al-4V: ASTM F136, and commercially pure Ti, cpTi: ASTM F67), respectively; (2) examining the composition of human serum proteins adsorbed onto the surfaces of Co- and Ti-based Implant Alloys; and (3) identifying the serum proteins associated with the binding of soluble Cr and Ti degradation products. Analysis of metal dissolution kinetics found that Cr was released from Co-based Implant Alloy at an order of magnitude higher than Ti was released from Ti-based Implant Alloys. Serum became saturated with soluble CR and Ti at levels as high as 3,250 ng/mL Ti from cpTi; 3,750 ng/mL Ti from Ti-6Al-4V; and 35,400 ng/mL Cr from Co-Cr-Mo degradation. The observation that human serum binds more released metal from Co-based Alloy dissolution was consistent with the observed differences in biofilm composition between the two Alloys, where additional serum protein(s) of approximately ≈140 (kDa) molecular weight were detected on Co-based Implant Alloy surfaces. However, both Cr and Ti released from Co- and Ti-based Alloys exhibited a bimodal binding pattern to both low molecular weight serum protein(s) (<32 kDa), and to higher molecular weight protein(s) in the 180–250 kDa range. Identification of metal Alloy–dependent biofilm compositions and dissolution products provides the basis for understanding the bioavailability and bioreactivity of these Implant Alloys and their degradation products. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 65A: 311–318, 2003

  • orthopaedic Implant related metal toxicity in terms of human lymphocyte reactivity to metal protein complexes produced from cobalt base and titanium base Implant Alloy degradation
    Molecular and Cellular Biochemistry, 2001
    Co-Authors: Nadim J Hallab, Csaba Vermes, Katalin Mikecz, Anastasia K Skipor, Joshua J Jacobs
    Abstract:

    Metal toxicity from sources such as orthopaedic Implants was investigated in terms of immune system hyper-reactivity to metal Implant Alloy degradation products. Lymphocyte response to serum protein complexed with metal from Implant Alloy degradation was investigated in this in vitro study using primary human lymphocytes from healthy volunteers (n = 10). Cobalt chromium molybdenum Alloy (Co‐Cr‐Mo, ASTM F‐75) and titanium Alloy (Ti‐6Al‐4V, ASTM F‐136) beads (70 μm) were incubated in agitated human serum at 37 degrees Celsius to simulate naturally occurring metal Implant Alloy degradation processes. Particulate free serum samples, which were incubated with metal, were then separated into molecular weight based fractions. The amounts of soluble Cr and Ti within each serum fraction were measured and correlated with lymphocyte proliferation response to the individual serum fractions. Lymphocytes from each subject were cultured with 11 autologous molecular weight based serum fractions either with or without added metal. Two molecular weight ranges of human serum proteins were associated with the binding of Cr and Ti from Co‐Cr‐Mo and Ti Implant Alloy degradation (at < 30 and 180–330 kDa). High molecular weight serum proteins (≈ 180 kDa) demonstrated greater lymphocyte reactivity when complexed with metal released from Co‐Cr‐Mo Alloy and Ti Alloy than with low (5–30 kDa) and midrange (30–77 kDa) serum proteins. When the amount of lymphocyte stimulation was normalized to both the moles of metal and the moles of protein within each fraction (Metal‐Protein Complex Reactivity Index, MPCRI), Cr from Co‐Cr‐Mo Alloy degradation demonstrated approximately 10 fold greater reactivity than Ti in the higher molecular weight serum proteins (≈ 180–250 kDa). This in vitro study demonstrated a lymphocyte proliferative response to both Co‐Cr‐Mo and Ti Alloy metalloprotein degradation products. This response was greatest when the metals were complexed with high molecular weight proteins, and with metal‐protein complexes formed from Co‐Cr‐Mo Alloy degradation.

  • differential lymphocyte reactivity to serum derived metal protein complexes produced from cobalt based and titanium based Implant Alloy degradation
    Journal of Biomedical Materials Research, 2001
    Co-Authors: Nadim J Hallab, Csaba Vermes, Katalin Mikecz, Anastasia K Skipor, Joshua J Jacobs
    Abstract:

    The lymphocyte response to serum protein complexed with metal from Implant Alloy degradation was investigated in this in vitro study using primary human lymphocytes from healthy volunteers (n = 10). Cobalt chromium molybdenum Alloy (Co-Cr-Mo, ASTM F-75) and titanium Alloy (Ti-6Al-4V, ASTM F-136) beads (70 μm) were incubated in agitated human serum at 37°C to simulate naturally occurring metal Implant Alloy degradation processes. Particulate free serum samples that had been incubated with metal were then separated into molecular weight based fractions. The amounts of soluble Cr and Ti within each serum fraction were measured and correlated with lymphocyte proliferation response to the individual serum fractions. Lymphocytes from each subject were cultured with 11 autologous molecular weight based serum fractions either with or without added metal. Two molecular weight ranges of human serum proteins were associated with the binding of Cr and Ti from Co-Cr-Mo and Ti Implant Alloy degradation (at <30 and 180–250 kDa). High molecular weight serum proteins (∼180 kDa) demonstrated greater lymphocyte reactivity when complexed with Cr Alloy and Ti Alloy than low (5–30 kDa) and midrange (30–77 kDa) serum proteins. When the amount of lymphocyte stimulation was normalized to both the moles of metal and the moles of protein within each fraction (metal–protein complex reactivity index), Cr from Co-Cr-Mo Alloy degradation demonstrated approximately 10-fold greater reactivity than Ti in the higher molecular weight serum proteins (∼180 kDa). This in vitro study demonstrated a lymphocyte proliferative response to both Co-Cr-Mo and Ti Alloy metalloprotein degradation products. This response was greatest when the metals were complexed with high molecular weight proteins, and with metal–protein complexes formed from Co-Cr-Mo Alloy degradation. © 2001 John Wiley & Sons, Inc. J Biomed Mater Res 56: 427–436, 2001

  • differential lymphocyte reactivity to serum derived metal protein complexes produced from cobalt based and titanium based Implant Alloy degradation
    Journal of Biomedical Materials Research, 2001
    Co-Authors: Nadim J Hallab, Csaba Vermes, Katalin Mikecz, Anastasia K Skipor, Joshua J Jacobs
    Abstract:

    The lymphocyte response to serum protein complexed with metal from Implant Alloy degradation was investigated in this in vitro study using primary human lymphocytes from healthy volunteers (n = 10). Cobalt chromium molybdenum Alloy (Co-Cr-Mo, ASTM F-75) and titanium Alloy (Ti-6Al-4V, ASTM F-136) beads (70 microm) were incubated in agitated human serum at 37 degrees C to simulate naturally occurring metal Implant Alloy degradation processes. Particulate free serum samples that had been incubated with metal were then separated into molecular weight based fractions. The amounts of soluble Cr and Ti within each serum fraction were measured and correlated with lymphocyte proliferation response to the individual serum fractions. Lymphocytes from each subject were cultured with 11 autologous molecular weight based serum fractions either with or without added metal. Two molecular weight ranges of human serum proteins were associated with the binding of Cr and Ti from Co-Cr-Mo and Ti Implant Alloy degradation (at <30 and 180-250 kDa). High molecular weight serum proteins ( approximately 180 kDa) demonstrated greater lymphocyte reactivity when complexed with Cr Alloy and Ti Alloy than low (5-30 kDa) and midrange (30-77 kDa) serum proteins. When the amount of lymphocyte stimulation was normalized to both the moles of metal and the moles of protein within each fraction (metal-protein complex reactivity index), Cr from Co-Cr-Mo Alloy degradation demonstrated approximately 10-fold greater reactivity than Ti in the higher molecular weight serum proteins ( approximately 180 kDa). This in vitro study demonstrated a lymphocyte proliferative response to both Co-Cr-Mo and Ti Alloy metalloprotein degradation products. This response was greatest when the metals were complexed with high molecular weight proteins, and with metal-protein complexes formed from Co-Cr-Mo Alloy degradation.

Yisui Chen - One of the best experts on this subject based on the ideXlab platform.

  • electrochemical corrosion studies on co cr mo Implant Alloy in biological solutions
    Materials Chemistry and Physics, 2005
    Co-Authors: Chunchen Yang, Chingan Huang, Yisui Chen
    Abstract:

    Abstract The electrochemical corrosion behavior of Co–Cr–Mo Implant Alloys in different biological solutions including urine, serum and joint fluid, was studied by using potentiodynamic scan method, cyclic voltammetry (CV), and ac impedance spectroscopy. The corrosion characteristic properties of Co–Cr–Mo Implant Alloys were investigated in terms of corrosion potential (Ecorr), corrosion current density (icorr), and ac polarization resistance (Rp). Based on the result of CV, the Co–Cr–Mo Implant Alloy only exhibits small passive region in joint fluid and serum, but a much large region for urine. However, the corrosion resistance of Co–Cr–Mo Implant Alloys in urine (5128 Ω cm2) was slightly lower than that in joint fluid (6513 Ω cm2) and serum (6691 Ω cm2) at Ecorr and 37 °C based on the result ac analyses. On the other hand, it was found that the corrosion current densities (icorr) of Co–Cr–Mo Implant Alloys in three biological solutions were comparable, at a range of 1.65–2.59 μA cm−2. A simple Randles circuit model could be used to approximate the corrosion interface of Co–Cr–Mo Implant Alloy in three biological solutions. It was also experimentally observed that the corrosion interface of Co–Cr–Mo Implant Alloy in biological solutions showed a characteristic of a capacitive behavior. Finally, the experimental results of Tafel plot analyses were found in good agreement with that of ac impedance analyses.

  • electrochemical corrosion properties of ti 6al 4v Implant Alloy in the biological environment
    Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2004
    Co-Authors: Chunchen Yang, Chingan Huang, Yisui Chen
    Abstract:

    Abstract The electrochemical corrosion behavior of Ti–6Al–4V Implant Alloy was investigated in three biological solutions, i.e. urine, serum and joint fluid. The corrosion properties of Ti–6Al–4V Implant Alloys were examined by using electrochemical techniques, such as the potentiodynamic method, cyclic voltammetry, electrochemical impedance spectroscopy (EIS). The electrochemical corrosion characteristics of Ti–6Al–4V Implant Alloys in three biological solutions were measured in terms of the corrosion potential (Ecorr), the corrosion current density (icorr), and ac polarization resistance (Rp). The corrosion kinetic parameters were calculated from both the Tafel plot analyses and EIS analyses. The dependence of impedance versus potentials was studied at 37 °C at various offset potentials in three biological solutions. The ac circuit model for Ti–6Al–4V Implant Alloy at corrosion interface in biological solution was proposed, which was based on a simple Randles equivalent circuit. It was found that the Ti–6Al–4V Implant Alloy in three biological solutions showed a characteristic of a capacitive behavior. The experimental results of Tafel plot analyses were found in good agreement with that of EIS analyses.

Katalin Mikecz - One of the best experts on this subject based on the ideXlab platform.

  • orthopaedic Implant related metal toxicity in terms of human lymphocyte reactivity to metal protein complexes produced from cobalt base and titanium base Implant Alloy degradation
    Molecular and Cellular Biochemistry, 2001
    Co-Authors: Nadim J Hallab, Csaba Vermes, Katalin Mikecz, Anastasia K Skipor, Joshua J Jacobs
    Abstract:

    Metal toxicity from sources such as orthopaedic Implants was investigated in terms of immune system hyper-reactivity to metal Implant Alloy degradation products. Lymphocyte response to serum protein complexed with metal from Implant Alloy degradation was investigated in this in vitro study using primary human lymphocytes from healthy volunteers (n = 10). Cobalt chromium molybdenum Alloy (Co‐Cr‐Mo, ASTM F‐75) and titanium Alloy (Ti‐6Al‐4V, ASTM F‐136) beads (70 μm) were incubated in agitated human serum at 37 degrees Celsius to simulate naturally occurring metal Implant Alloy degradation processes. Particulate free serum samples, which were incubated with metal, were then separated into molecular weight based fractions. The amounts of soluble Cr and Ti within each serum fraction were measured and correlated with lymphocyte proliferation response to the individual serum fractions. Lymphocytes from each subject were cultured with 11 autologous molecular weight based serum fractions either with or without added metal. Two molecular weight ranges of human serum proteins were associated with the binding of Cr and Ti from Co‐Cr‐Mo and Ti Implant Alloy degradation (at < 30 and 180–330 kDa). High molecular weight serum proteins (≈ 180 kDa) demonstrated greater lymphocyte reactivity when complexed with metal released from Co‐Cr‐Mo Alloy and Ti Alloy than with low (5–30 kDa) and midrange (30–77 kDa) serum proteins. When the amount of lymphocyte stimulation was normalized to both the moles of metal and the moles of protein within each fraction (Metal‐Protein Complex Reactivity Index, MPCRI), Cr from Co‐Cr‐Mo Alloy degradation demonstrated approximately 10 fold greater reactivity than Ti in the higher molecular weight serum proteins (≈ 180–250 kDa). This in vitro study demonstrated a lymphocyte proliferative response to both Co‐Cr‐Mo and Ti Alloy metalloprotein degradation products. This response was greatest when the metals were complexed with high molecular weight proteins, and with metal‐protein complexes formed from Co‐Cr‐Mo Alloy degradation.

  • differential lymphocyte reactivity to serum derived metal protein complexes produced from cobalt based and titanium based Implant Alloy degradation
    Journal of Biomedical Materials Research, 2001
    Co-Authors: Nadim J Hallab, Csaba Vermes, Katalin Mikecz, Anastasia K Skipor, Joshua J Jacobs
    Abstract:

    The lymphocyte response to serum protein complexed with metal from Implant Alloy degradation was investigated in this in vitro study using primary human lymphocytes from healthy volunteers (n = 10). Cobalt chromium molybdenum Alloy (Co-Cr-Mo, ASTM F-75) and titanium Alloy (Ti-6Al-4V, ASTM F-136) beads (70 μm) were incubated in agitated human serum at 37°C to simulate naturally occurring metal Implant Alloy degradation processes. Particulate free serum samples that had been incubated with metal were then separated into molecular weight based fractions. The amounts of soluble Cr and Ti within each serum fraction were measured and correlated with lymphocyte proliferation response to the individual serum fractions. Lymphocytes from each subject were cultured with 11 autologous molecular weight based serum fractions either with or without added metal. Two molecular weight ranges of human serum proteins were associated with the binding of Cr and Ti from Co-Cr-Mo and Ti Implant Alloy degradation (at <30 and 180–250 kDa). High molecular weight serum proteins (∼180 kDa) demonstrated greater lymphocyte reactivity when complexed with Cr Alloy and Ti Alloy than low (5–30 kDa) and midrange (30–77 kDa) serum proteins. When the amount of lymphocyte stimulation was normalized to both the moles of metal and the moles of protein within each fraction (metal–protein complex reactivity index), Cr from Co-Cr-Mo Alloy degradation demonstrated approximately 10-fold greater reactivity than Ti in the higher molecular weight serum proteins (∼180 kDa). This in vitro study demonstrated a lymphocyte proliferative response to both Co-Cr-Mo and Ti Alloy metalloprotein degradation products. This response was greatest when the metals were complexed with high molecular weight proteins, and with metal–protein complexes formed from Co-Cr-Mo Alloy degradation. © 2001 John Wiley & Sons, Inc. J Biomed Mater Res 56: 427–436, 2001

  • differential lymphocyte reactivity to serum derived metal protein complexes produced from cobalt based and titanium based Implant Alloy degradation
    Journal of Biomedical Materials Research, 2001
    Co-Authors: Nadim J Hallab, Csaba Vermes, Katalin Mikecz, Anastasia K Skipor, Joshua J Jacobs
    Abstract:

    The lymphocyte response to serum protein complexed with metal from Implant Alloy degradation was investigated in this in vitro study using primary human lymphocytes from healthy volunteers (n = 10). Cobalt chromium molybdenum Alloy (Co-Cr-Mo, ASTM F-75) and titanium Alloy (Ti-6Al-4V, ASTM F-136) beads (70 microm) were incubated in agitated human serum at 37 degrees C to simulate naturally occurring metal Implant Alloy degradation processes. Particulate free serum samples that had been incubated with metal were then separated into molecular weight based fractions. The amounts of soluble Cr and Ti within each serum fraction were measured and correlated with lymphocyte proliferation response to the individual serum fractions. Lymphocytes from each subject were cultured with 11 autologous molecular weight based serum fractions either with or without added metal. Two molecular weight ranges of human serum proteins were associated with the binding of Cr and Ti from Co-Cr-Mo and Ti Implant Alloy degradation (at <30 and 180-250 kDa). High molecular weight serum proteins ( approximately 180 kDa) demonstrated greater lymphocyte reactivity when complexed with Cr Alloy and Ti Alloy than low (5-30 kDa) and midrange (30-77 kDa) serum proteins. When the amount of lymphocyte stimulation was normalized to both the moles of metal and the moles of protein within each fraction (metal-protein complex reactivity index), Cr from Co-Cr-Mo Alloy degradation demonstrated approximately 10-fold greater reactivity than Ti in the higher molecular weight serum proteins ( approximately 180 kDa). This in vitro study demonstrated a lymphocyte proliferative response to both Co-Cr-Mo and Ti Alloy metalloprotein degradation products. This response was greatest when the metals were complexed with high molecular weight proteins, and with metal-protein complexes formed from Co-Cr-Mo Alloy degradation.