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Yuehe Lin - One of the best experts on this subject based on the ideXlab platform.

  • nanoparticle based electrochemical immunosensor for the detection of phosphorylated acetylcholinesterase an exposure biomarker of organophosphate pesticides and nerve agents
    Chemistry: A European Journal, 2008
    Co-Authors: Guodong Liu, Jun Wang, Richard C Barry, Catherine E Petersen, Charles Timchalk, Paul L Gassman, Yuehe Lin
    Abstract:

    A nanoparticle-based electrochemical immunosensor has been developed for the detection of phosphorylated acetylcholinesterase (AChE), which is a potential biomarker of exposure to organophosphate (OP) pesticides and chemical warfare nerve agents. Zirconia nanoparticles (ZrO(2) NPs) were used as selective sorbents to capture the phosphorylated AChE adduct, and quantum dots (ZnS@CdS, QDs) were used as tags to label monoclonal anti-AChE antibody to quantify the immunorecognition events. The sandwich-like immunoreactions were performed among the ZrO(2) NPs, which were pre-coated on a screen printed electrode (SPE) by electrodeposition, phosphorylated AChE and QD-anti-AChE. The captured QD tags were determined on the SPE by electrochemical stripping analysis of its Metallic Component (cadmium) after an acid-dissolution step. Paraoxon was used as the model OP insecticide to prepare the phosphorylated AChE adducts to demonstrate proof of principle for the sensor. The phosphorylated AChE adduct was characterized by Fourier transform infrared spectroscopy (FTIR) and mass spectroscopy. The binding affinity of anti-AChE to the phosphorylated AChE was validated with an enzyme-linked immunosorbent assay. The parameters (e.g., amount of ZrO(2) NP, QD-anti-AChE concentration,) that govern the electrochemical response of immunosensors were optimized. The voltammetric response of the immunosensor is highly linear over the range of 10 pM to 4 nM phosphorylated AChE, and the limit of detection is estimated to be 8.0 pM. The immunosensor also successfully detected phosphorylated AChE in human plasma. This new nanoparticle-based electrochemical immunosensor provides an opportunity to develop field-deployable, sensitive, and quantitative biosensors for monitoring exposure to a variety of OP pesticides and nerve agents.

  • nanoparticle based electrochemical immunosensor for the detection of phosphorylated acetylcholinesterase an exposure biomarker of organophosphate pesticides and nerve agentsorganophosphate pesticides and nerve agents
    Chemistry: A European Journal, 2008
    Co-Authors: Guodong Liu, Jun Wang, Richard C Barry, Catherine E Petersen, Charles Timchalk, Paul L Gassman, Yuehe Lin
    Abstract:

    A nanoparticle-based electrochemical immunosensor has been developed for the detection of phosphorylated acetylcholinesterase (AChE) adducts, which is a potential exposure biomarker for organophosphate pesticides (OP) and chemical warfare nerve agent exposures. Zirconia nanoparticles (ZrO2 NPs) were used as selective sorbents to capture the phosphorylated AChE adduct, and quantum dots (ZnS@CdS, QDs) were used as tags to label monoclonal anti-AChE antibody to track the immunorecognition events. The sandwich-like immunoreactions were performed among the ZrO2 NPs, which were pre-coated on a screen printed electrode (SPE) by electrodeposition, phosphorylated AChE and QD-anti-AChE. The captured QD tags were determined on the SPE by electrochemical stripping analysis of its Metallic Component (cadmium) after an acid-dissolution step. Paraoxon was used as a model OP insecticide to prepare the phosphorylated AChE adduct to demonstrate the proof of principle for this sensor technology. The paraoxon-AChE adduct was characterized by Fourier Transform Infrared Spectrum, and the binding affinity of anti-AChE to the paraoxon-AChE was validated with an enzyme-linked immunosorbent assay. The parameters (e.g., amount of ZrO2 NP, QD-anti-AChE concentration,) that govern the electrochemical response of immunosensors were optimized. The voltammetric response of the immunosensor is highly linear over the range of 10 pM to 4 nM paraoxon-AChE, and themore » limit of detection is estimated to be 8 pM. This new nanoparticle-based electrochemical immunosensor thus provides a sensitive and quantitative tool for biomonitoring exposure to OP pesticides and nerve agents.« less

  • a nanoparticle label immunochromatographic electrochemical biosensor for rapid and sensitive detection of prostate specific antigen
    Biosensors and Bioelectronics, 2008
    Co-Authors: Guodong Liu, Ying Ying Lin, Jun Wang, Chien M Wai, Yuehe Lin
    Abstract:

    We present a nanoparticle (NP) label/immunochromatographic electrochemical biosensor (IEB) for rapid and sensitive detection of prostate-specific antigen (PSA) in human serum. This IEB integrates the immunochromatographic strip with the electrochemical detector for transducing quantitative signals. The NP label, made of CdSe@ZnS, serves as a signal-amplifier vehicle. A sandwich immunoreaction was performed on the immunochromatographic strip. The captured NP labels in the test zone were determined by highly sensitive stripping voltammetric measurement of the dissolved Metallic Component (cadmium) with a disposable-screen-printed electrode, which is embedded underneath the membrane of the test zone. Several experimental parameters (e.g., immunoreaction time, the amount of anti-PSA-NP conjugations applied) and electrochemical detection conditions (e.g., preconcentration potential and time) were optimized using this biosensor for PSA detection. The analytical performance of this biosensor was evaluated with serum PSA samples according to the "figure-of-merits" (e.g., dynamic range, reproducibility, and detection limit). The results were validated with enzyme-linked immunosorbent assay (ELISA) and showed high consistency. It is found that this biosensor is very sensitive with the detection limit of 0.02ngmL(-1) PSA and is quite reproducible (with a relative standard deviation (R.S.D.) of 6.4%). This method is rapid, clinically practical, and less expensive than other diagnostic tools for PSA; therefore, this IEB coupled with a portable electrochemical analyzer shows great promise for simple, sensitive, quantitative point-of-care testing of disease-related protein biomarkers.

  • disposable electrochemical immunosensor diagnosis device based on nanoparticle probe and immunochromatographic strip
    Analytical Chemistry, 2007
    Co-Authors: Guodong Liu, Ying Ying Lin, Jun Wang, Chien M Wai, Yuehe Lin
    Abstract:

    We describe a disposable electrochemical immunosensor diagnosis device that integrates the immunochromatographic strip technique with an electrochemical immunoassay and exploits quantum dot (QD, CdS@ZnS) as labels for amplifying signal output. The device takes advantage of the speed and low cost of the conventional immunochromatographic strip test and the high sensitivity of the nanoparticle-based electrochemical immunoassay. A sandwich immunoreaction was performed on the immunochromatographic strip, and the captured QD labels in the test zone were determined by highly sensitive stripping voltammetric measurement of the dissolved Metallic Component (cadmium) with a disposable screen-printed electrode, which is embedded underneath the membrane on the test zone. The new device coupled with a portable electrochemical analyzer shows great promise for in-field and point-of-care quantitative testing of disease-related protein biomarkers. The parameters (e.g., voltammetric measurement of QD labels, antibody immo...

Guodong Liu - One of the best experts on this subject based on the ideXlab platform.

  • nanoparticle based electrochemical immunosensor for the detection of phosphorylated acetylcholinesterase an exposure biomarker of organophosphate pesticides and nerve agents
    Chemistry: A European Journal, 2008
    Co-Authors: Guodong Liu, Jun Wang, Richard C Barry, Catherine E Petersen, Charles Timchalk, Paul L Gassman, Yuehe Lin
    Abstract:

    A nanoparticle-based electrochemical immunosensor has been developed for the detection of phosphorylated acetylcholinesterase (AChE), which is a potential biomarker of exposure to organophosphate (OP) pesticides and chemical warfare nerve agents. Zirconia nanoparticles (ZrO(2) NPs) were used as selective sorbents to capture the phosphorylated AChE adduct, and quantum dots (ZnS@CdS, QDs) were used as tags to label monoclonal anti-AChE antibody to quantify the immunorecognition events. The sandwich-like immunoreactions were performed among the ZrO(2) NPs, which were pre-coated on a screen printed electrode (SPE) by electrodeposition, phosphorylated AChE and QD-anti-AChE. The captured QD tags were determined on the SPE by electrochemical stripping analysis of its Metallic Component (cadmium) after an acid-dissolution step. Paraoxon was used as the model OP insecticide to prepare the phosphorylated AChE adducts to demonstrate proof of principle for the sensor. The phosphorylated AChE adduct was characterized by Fourier transform infrared spectroscopy (FTIR) and mass spectroscopy. The binding affinity of anti-AChE to the phosphorylated AChE was validated with an enzyme-linked immunosorbent assay. The parameters (e.g., amount of ZrO(2) NP, QD-anti-AChE concentration,) that govern the electrochemical response of immunosensors were optimized. The voltammetric response of the immunosensor is highly linear over the range of 10 pM to 4 nM phosphorylated AChE, and the limit of detection is estimated to be 8.0 pM. The immunosensor also successfully detected phosphorylated AChE in human plasma. This new nanoparticle-based electrochemical immunosensor provides an opportunity to develop field-deployable, sensitive, and quantitative biosensors for monitoring exposure to a variety of OP pesticides and nerve agents.

  • nanoparticle based electrochemical immunosensor for the detection of phosphorylated acetylcholinesterase an exposure biomarker of organophosphate pesticides and nerve agentsorganophosphate pesticides and nerve agents
    Chemistry: A European Journal, 2008
    Co-Authors: Guodong Liu, Jun Wang, Richard C Barry, Catherine E Petersen, Charles Timchalk, Paul L Gassman, Yuehe Lin
    Abstract:

    A nanoparticle-based electrochemical immunosensor has been developed for the detection of phosphorylated acetylcholinesterase (AChE) adducts, which is a potential exposure biomarker for organophosphate pesticides (OP) and chemical warfare nerve agent exposures. Zirconia nanoparticles (ZrO2 NPs) were used as selective sorbents to capture the phosphorylated AChE adduct, and quantum dots (ZnS@CdS, QDs) were used as tags to label monoclonal anti-AChE antibody to track the immunorecognition events. The sandwich-like immunoreactions were performed among the ZrO2 NPs, which were pre-coated on a screen printed electrode (SPE) by electrodeposition, phosphorylated AChE and QD-anti-AChE. The captured QD tags were determined on the SPE by electrochemical stripping analysis of its Metallic Component (cadmium) after an acid-dissolution step. Paraoxon was used as a model OP insecticide to prepare the phosphorylated AChE adduct to demonstrate the proof of principle for this sensor technology. The paraoxon-AChE adduct was characterized by Fourier Transform Infrared Spectrum, and the binding affinity of anti-AChE to the paraoxon-AChE was validated with an enzyme-linked immunosorbent assay. The parameters (e.g., amount of ZrO2 NP, QD-anti-AChE concentration,) that govern the electrochemical response of immunosensors were optimized. The voltammetric response of the immunosensor is highly linear over the range of 10 pM to 4 nM paraoxon-AChE, and themore » limit of detection is estimated to be 8 pM. This new nanoparticle-based electrochemical immunosensor thus provides a sensitive and quantitative tool for biomonitoring exposure to OP pesticides and nerve agents.« less

  • a nanoparticle label immunochromatographic electrochemical biosensor for rapid and sensitive detection of prostate specific antigen
    Biosensors and Bioelectronics, 2008
    Co-Authors: Guodong Liu, Ying Ying Lin, Jun Wang, Chien M Wai, Yuehe Lin
    Abstract:

    We present a nanoparticle (NP) label/immunochromatographic electrochemical biosensor (IEB) for rapid and sensitive detection of prostate-specific antigen (PSA) in human serum. This IEB integrates the immunochromatographic strip with the electrochemical detector for transducing quantitative signals. The NP label, made of CdSe@ZnS, serves as a signal-amplifier vehicle. A sandwich immunoreaction was performed on the immunochromatographic strip. The captured NP labels in the test zone were determined by highly sensitive stripping voltammetric measurement of the dissolved Metallic Component (cadmium) with a disposable-screen-printed electrode, which is embedded underneath the membrane of the test zone. Several experimental parameters (e.g., immunoreaction time, the amount of anti-PSA-NP conjugations applied) and electrochemical detection conditions (e.g., preconcentration potential and time) were optimized using this biosensor for PSA detection. The analytical performance of this biosensor was evaluated with serum PSA samples according to the "figure-of-merits" (e.g., dynamic range, reproducibility, and detection limit). The results were validated with enzyme-linked immunosorbent assay (ELISA) and showed high consistency. It is found that this biosensor is very sensitive with the detection limit of 0.02ngmL(-1) PSA and is quite reproducible (with a relative standard deviation (R.S.D.) of 6.4%). This method is rapid, clinically practical, and less expensive than other diagnostic tools for PSA; therefore, this IEB coupled with a portable electrochemical analyzer shows great promise for simple, sensitive, quantitative point-of-care testing of disease-related protein biomarkers.

  • disposable electrochemical immunosensor diagnosis device based on nanoparticle probe and immunochromatographic strip
    Analytical Chemistry, 2007
    Co-Authors: Guodong Liu, Ying Ying Lin, Jun Wang, Chien M Wai, Yuehe Lin
    Abstract:

    We describe a disposable electrochemical immunosensor diagnosis device that integrates the immunochromatographic strip technique with an electrochemical immunoassay and exploits quantum dot (QD, CdS@ZnS) as labels for amplifying signal output. The device takes advantage of the speed and low cost of the conventional immunochromatographic strip test and the high sensitivity of the nanoparticle-based electrochemical immunoassay. A sandwich immunoreaction was performed on the immunochromatographic strip, and the captured QD labels in the test zone were determined by highly sensitive stripping voltammetric measurement of the dissolved Metallic Component (cadmium) with a disposable screen-printed electrode, which is embedded underneath the membrane on the test zone. The new device coupled with a portable electrochemical analyzer shows great promise for in-field and point-of-care quantitative testing of disease-related protein biomarkers. The parameters (e.g., voltammetric measurement of QD labels, antibody immo...

James A Nunley - One of the best experts on this subject based on the ideXlab platform.

  • early prospective clinical results of a modern fixed bearing total ankle arthroplasty
    Journal of Bone and Joint Surgery American Volume, 2013
    Co-Authors: Karl M Schweitzer, Samuel B Adams, Nicholas A Viens, Robin M Queen, Mark E Easley, James K Deorio, James A Nunley
    Abstract:

    Background: Several fixed-bearing total ankle arthroplasty systems are available in the United States. We report on the early clinical results of the largest known cohort of patients in the United States who received a Salto Talaris total ankle replacement for the treatment of end-stage arthritis of the ankle. Methods: We prospectively followed sixty-seven patients with a minimum clinical follow-up of two years. Patients completed standardized assessments and underwent physical examination, functional assessment, and radiographic evaluation preoperatively and at six weeks, three months, and six months postoperatively and yearly thereafter through their most recent follow-up. Results: Implant survival at a mean follow-up time of 2.8 years was 96% when Metallic Component revision, removal, or impending failure was used as the end point. Three patients developed aseptic loosening, and all instances involved the tibial Component. One of the three patients underwent revision to another fixed-bearing total ankle arthroplasty system, one patient is awaiting revision surgery, and the third patient has remained minimally symptomatic and fully functional without additional surgery. Forty-five patients underwent at least one additional procedure at the time of the index surgery. The most common concurrent procedure performed was a deltoid ligament release (n = 21). Eight patients underwent additional surgery following the index arthroplasty, most commonly debridement for medial and/or lateral impingement (n = 4). As of the most recent follow-up, patients demonstrated significant improvement in pain scores, American Orthopaedic Foot & Ankle Society hindfoot score, and functional scores. Conclusions: Early clinical results indicate that the Salto Talaris fixed-bearing total ankle arthroplasty system can provide significant improvement in pain, quality of life, and standard functional measures in patients with end-stage ankle arthritis. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

  • intermediate to long term outcomes of the star total ankle replacement the patient perspective
    Journal of Bone and Joint Surgery American Volume, 2012
    Co-Authors: James A Nunley, Mark E Easley, Adam M Caputo, Chad Cook
    Abstract:

    Background: The purpose of the present study was to document the patient self-reported improvements in quality of life, function, and overall impairment scores, as well as the improvement in the clinically derived outcome scores, following a Scandinavian Total Ankle Replacement (STAR) arthroplasty performed for the treatment of end-stage ankle arthritis. Methods: All patients who underwent a Scandinavian Total Ankle Replacement arthroplasty from July 1998 through February 2008 were prospectively followed and retrospectively reviewed. All surgical procedures were performed by a single surgeon. Preoperatively and at subsequent follow-up visits, patients were assessed with (1) a visual analog scale (VAS) score for pain, (2) the Short Form-36 (SF-36) quality-of-life scale, (3) the American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot scale and subscales, (4) the Buechel-Pappas pain and function scores, and (5) the ankle range of motion. Additional measures that were recorded included (1) concomitant surgical procedures during the initial ankle replacement, (2) revision surgery during the follow-up period, and (3) any additional surgical procedures. Revision was defined as failure of either the tibial or the talar Metallic Component that required removal of a Metallic implant for any reason. Results: Eighty-two consecutive patients were evaluated. The duration of follow-up ranged from twenty-four to 108 months (mean, sixty-one months; median, sixty months). During the follow-up period, three patients died and six patients moved out of the region. The latter six patients were followed by another surgeon group, and their data were included. Eight patients were lost to follow-up after twelve months. There were significant improvements in all outcome categories between the preoperative and postoperative evaluations. The most compelling finding of the present study involved the marked improvement in terms of the self-reported measures of impairments, quality of life, pain, and function. Conclusions: Total ankle arthroplasty with the Scandinavian Total Ankle Replacement prosthesis was associated with significant improvements in terms of pain, function, and quality of life after intermediate to long-term follow-up. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Jun Wang - One of the best experts on this subject based on the ideXlab platform.

  • nanoparticle based electrochemical immunosensor for the detection of phosphorylated acetylcholinesterase an exposure biomarker of organophosphate pesticides and nerve agents
    Chemistry: A European Journal, 2008
    Co-Authors: Guodong Liu, Jun Wang, Richard C Barry, Catherine E Petersen, Charles Timchalk, Paul L Gassman, Yuehe Lin
    Abstract:

    A nanoparticle-based electrochemical immunosensor has been developed for the detection of phosphorylated acetylcholinesterase (AChE), which is a potential biomarker of exposure to organophosphate (OP) pesticides and chemical warfare nerve agents. Zirconia nanoparticles (ZrO(2) NPs) were used as selective sorbents to capture the phosphorylated AChE adduct, and quantum dots (ZnS@CdS, QDs) were used as tags to label monoclonal anti-AChE antibody to quantify the immunorecognition events. The sandwich-like immunoreactions were performed among the ZrO(2) NPs, which were pre-coated on a screen printed electrode (SPE) by electrodeposition, phosphorylated AChE and QD-anti-AChE. The captured QD tags were determined on the SPE by electrochemical stripping analysis of its Metallic Component (cadmium) after an acid-dissolution step. Paraoxon was used as the model OP insecticide to prepare the phosphorylated AChE adducts to demonstrate proof of principle for the sensor. The phosphorylated AChE adduct was characterized by Fourier transform infrared spectroscopy (FTIR) and mass spectroscopy. The binding affinity of anti-AChE to the phosphorylated AChE was validated with an enzyme-linked immunosorbent assay. The parameters (e.g., amount of ZrO(2) NP, QD-anti-AChE concentration,) that govern the electrochemical response of immunosensors were optimized. The voltammetric response of the immunosensor is highly linear over the range of 10 pM to 4 nM phosphorylated AChE, and the limit of detection is estimated to be 8.0 pM. The immunosensor also successfully detected phosphorylated AChE in human plasma. This new nanoparticle-based electrochemical immunosensor provides an opportunity to develop field-deployable, sensitive, and quantitative biosensors for monitoring exposure to a variety of OP pesticides and nerve agents.

  • nanoparticle based electrochemical immunosensor for the detection of phosphorylated acetylcholinesterase an exposure biomarker of organophosphate pesticides and nerve agentsorganophosphate pesticides and nerve agents
    Chemistry: A European Journal, 2008
    Co-Authors: Guodong Liu, Jun Wang, Richard C Barry, Catherine E Petersen, Charles Timchalk, Paul L Gassman, Yuehe Lin
    Abstract:

    A nanoparticle-based electrochemical immunosensor has been developed for the detection of phosphorylated acetylcholinesterase (AChE) adducts, which is a potential exposure biomarker for organophosphate pesticides (OP) and chemical warfare nerve agent exposures. Zirconia nanoparticles (ZrO2 NPs) were used as selective sorbents to capture the phosphorylated AChE adduct, and quantum dots (ZnS@CdS, QDs) were used as tags to label monoclonal anti-AChE antibody to track the immunorecognition events. The sandwich-like immunoreactions were performed among the ZrO2 NPs, which were pre-coated on a screen printed electrode (SPE) by electrodeposition, phosphorylated AChE and QD-anti-AChE. The captured QD tags were determined on the SPE by electrochemical stripping analysis of its Metallic Component (cadmium) after an acid-dissolution step. Paraoxon was used as a model OP insecticide to prepare the phosphorylated AChE adduct to demonstrate the proof of principle for this sensor technology. The paraoxon-AChE adduct was characterized by Fourier Transform Infrared Spectrum, and the binding affinity of anti-AChE to the paraoxon-AChE was validated with an enzyme-linked immunosorbent assay. The parameters (e.g., amount of ZrO2 NP, QD-anti-AChE concentration,) that govern the electrochemical response of immunosensors were optimized. The voltammetric response of the immunosensor is highly linear over the range of 10 pM to 4 nM paraoxon-AChE, and themore » limit of detection is estimated to be 8 pM. This new nanoparticle-based electrochemical immunosensor thus provides a sensitive and quantitative tool for biomonitoring exposure to OP pesticides and nerve agents.« less

  • a nanoparticle label immunochromatographic electrochemical biosensor for rapid and sensitive detection of prostate specific antigen
    Biosensors and Bioelectronics, 2008
    Co-Authors: Guodong Liu, Ying Ying Lin, Jun Wang, Chien M Wai, Yuehe Lin
    Abstract:

    We present a nanoparticle (NP) label/immunochromatographic electrochemical biosensor (IEB) for rapid and sensitive detection of prostate-specific antigen (PSA) in human serum. This IEB integrates the immunochromatographic strip with the electrochemical detector for transducing quantitative signals. The NP label, made of CdSe@ZnS, serves as a signal-amplifier vehicle. A sandwich immunoreaction was performed on the immunochromatographic strip. The captured NP labels in the test zone were determined by highly sensitive stripping voltammetric measurement of the dissolved Metallic Component (cadmium) with a disposable-screen-printed electrode, which is embedded underneath the membrane of the test zone. Several experimental parameters (e.g., immunoreaction time, the amount of anti-PSA-NP conjugations applied) and electrochemical detection conditions (e.g., preconcentration potential and time) were optimized using this biosensor for PSA detection. The analytical performance of this biosensor was evaluated with serum PSA samples according to the "figure-of-merits" (e.g., dynamic range, reproducibility, and detection limit). The results were validated with enzyme-linked immunosorbent assay (ELISA) and showed high consistency. It is found that this biosensor is very sensitive with the detection limit of 0.02ngmL(-1) PSA and is quite reproducible (with a relative standard deviation (R.S.D.) of 6.4%). This method is rapid, clinically practical, and less expensive than other diagnostic tools for PSA; therefore, this IEB coupled with a portable electrochemical analyzer shows great promise for simple, sensitive, quantitative point-of-care testing of disease-related protein biomarkers.

  • disposable electrochemical immunosensor diagnosis device based on nanoparticle probe and immunochromatographic strip
    Analytical Chemistry, 2007
    Co-Authors: Guodong Liu, Ying Ying Lin, Jun Wang, Chien M Wai, Yuehe Lin
    Abstract:

    We describe a disposable electrochemical immunosensor diagnosis device that integrates the immunochromatographic strip technique with an electrochemical immunoassay and exploits quantum dot (QD, CdS@ZnS) as labels for amplifying signal output. The device takes advantage of the speed and low cost of the conventional immunochromatographic strip test and the high sensitivity of the nanoparticle-based electrochemical immunoassay. A sandwich immunoreaction was performed on the immunochromatographic strip, and the captured QD labels in the test zone were determined by highly sensitive stripping voltammetric measurement of the dissolved Metallic Component (cadmium) with a disposable screen-printed electrode, which is embedded underneath the membrane on the test zone. The new device coupled with a portable electrochemical analyzer shows great promise for in-field and point-of-care quantitative testing of disease-related protein biomarkers. The parameters (e.g., voltammetric measurement of QD labels, antibody immo...

Mark E Easley - One of the best experts on this subject based on the ideXlab platform.

  • early prospective clinical results of a modern fixed bearing total ankle arthroplasty
    Journal of Bone and Joint Surgery American Volume, 2013
    Co-Authors: Karl M Schweitzer, Samuel B Adams, Nicholas A Viens, Robin M Queen, Mark E Easley, James K Deorio, James A Nunley
    Abstract:

    Background: Several fixed-bearing total ankle arthroplasty systems are available in the United States. We report on the early clinical results of the largest known cohort of patients in the United States who received a Salto Talaris total ankle replacement for the treatment of end-stage arthritis of the ankle. Methods: We prospectively followed sixty-seven patients with a minimum clinical follow-up of two years. Patients completed standardized assessments and underwent physical examination, functional assessment, and radiographic evaluation preoperatively and at six weeks, three months, and six months postoperatively and yearly thereafter through their most recent follow-up. Results: Implant survival at a mean follow-up time of 2.8 years was 96% when Metallic Component revision, removal, or impending failure was used as the end point. Three patients developed aseptic loosening, and all instances involved the tibial Component. One of the three patients underwent revision to another fixed-bearing total ankle arthroplasty system, one patient is awaiting revision surgery, and the third patient has remained minimally symptomatic and fully functional without additional surgery. Forty-five patients underwent at least one additional procedure at the time of the index surgery. The most common concurrent procedure performed was a deltoid ligament release (n = 21). Eight patients underwent additional surgery following the index arthroplasty, most commonly debridement for medial and/or lateral impingement (n = 4). As of the most recent follow-up, patients demonstrated significant improvement in pain scores, American Orthopaedic Foot & Ankle Society hindfoot score, and functional scores. Conclusions: Early clinical results indicate that the Salto Talaris fixed-bearing total ankle arthroplasty system can provide significant improvement in pain, quality of life, and standard functional measures in patients with end-stage ankle arthritis. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

  • intermediate to long term outcomes of the star total ankle replacement the patient perspective
    Journal of Bone and Joint Surgery American Volume, 2012
    Co-Authors: James A Nunley, Mark E Easley, Adam M Caputo, Chad Cook
    Abstract:

    Background: The purpose of the present study was to document the patient self-reported improvements in quality of life, function, and overall impairment scores, as well as the improvement in the clinically derived outcome scores, following a Scandinavian Total Ankle Replacement (STAR) arthroplasty performed for the treatment of end-stage ankle arthritis. Methods: All patients who underwent a Scandinavian Total Ankle Replacement arthroplasty from July 1998 through February 2008 were prospectively followed and retrospectively reviewed. All surgical procedures were performed by a single surgeon. Preoperatively and at subsequent follow-up visits, patients were assessed with (1) a visual analog scale (VAS) score for pain, (2) the Short Form-36 (SF-36) quality-of-life scale, (3) the American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot scale and subscales, (4) the Buechel-Pappas pain and function scores, and (5) the ankle range of motion. Additional measures that were recorded included (1) concomitant surgical procedures during the initial ankle replacement, (2) revision surgery during the follow-up period, and (3) any additional surgical procedures. Revision was defined as failure of either the tibial or the talar Metallic Component that required removal of a Metallic implant for any reason. Results: Eighty-two consecutive patients were evaluated. The duration of follow-up ranged from twenty-four to 108 months (mean, sixty-one months; median, sixty months). During the follow-up period, three patients died and six patients moved out of the region. The latter six patients were followed by another surgeon group, and their data were included. Eight patients were lost to follow-up after twelve months. There were significant improvements in all outcome categories between the preoperative and postoperative evaluations. The most compelling finding of the present study involved the marked improvement in terms of the self-reported measures of impairments, quality of life, pain, and function. Conclusions: Total ankle arthroplasty with the Scandinavian Total Ankle Replacement prosthesis was associated with significant improvements in terms of pain, function, and quality of life after intermediate to long-term follow-up. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.