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Cohen IJ, Smith EJ, Clark GB, Turner DL, Ellison DH, Clare B, Regoli LH, Kollmann P, Gallagher DT, Holtzman GA, Likar JJ, Morizono T, Shannon M, Vodusek KS. Plasma Environment, Radiation, Structure, and Evolution of the Uranian System (PERSEUS): A Dedicated Orbiter Mission Concept to Study Space Physics at Uranus. Space Sci Rev 2023; 219:65. [PMID: 37869526 PMCID: PMC10587260 DOI: 10.1007/s11214-023-01013-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Accepted: 10/05/2023] [Indexed: 10/24/2023]
Abstract
The Plasma Environment, Radiation, Structure, and Evolution of the Uranian System (PERSEUS) mission concept defines the feasibility and potential scope of a dedicated, standalone Heliophysics orbiter mission to study multiple space physics science objectives at Uranus. Uranus's complex and dynamic magnetosphere presents a unique laboratory to study magnetospheric physics as well as its coupling to the solar wind and the planet's atmosphere, satellites, and rings. From the planet's tilted and offset, rapidly-rotating non-dipolar magnetic field to its seasonally-extreme interactions with the solar wind to its unexpectedly intense electron radiation belts, Uranus hosts a range of outstanding and compelling mysteries relevant to the space physics community. While the exploration of planets other than Earth has largely fallen within the purview of NASA's Planetary Science Division, many targets, like Uranus, also hold immense scientific value and interest to NASA's Heliophysics Division. Exploring and understanding Uranus's magnetosphere is critical to make fundamental gains in magnetospheric physics and the understanding of potential exoplanetary systems and to test the validity of our knowledge of magnetospheric dynamics, moon-magnetosphere interactions, magnetosphere-ionosphere coupling, and solar wind-planetary coupling. The PERSEUS mission concept study, currently at Concept Maturity Level (CML) 4, comprises a feasible payload that provides closure to a range of space physics science objectives in a reliable and mature spacecraft and mission design architecture. The mission is able to close using only a single Mod-1 Next-Generation Radioisotope Thermoelectric Generator (NG-RTG) by leveraging a concept of operations that relies of a significant hibernation mode for a large portion of its 22-day orbit.
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Affiliation(s)
- Ian J Cohen
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | - Evan J Smith
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | - George B Clark
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | - Drew L Turner
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | - Donald H Ellison
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | - Ben Clare
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | - Leonardo H Regoli
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | - Peter Kollmann
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | | | - G Allan Holtzman
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | - Justin J Likar
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | - Takeshi Morizono
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
| | - Matthew Shannon
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD USA
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Daly RT, Ernst CM, Barnouin OS, Chabot NL, Rivkin AS, Cheng AF, Adams EY, Agrusa HF, Abel ED, Alford AL, Asphaug EI, Atchison JA, Badger AR, Baki P, Ballouz RL, Bekker DL, Bellerose J, Bhaskaran S, Buratti BJ, Cambioni S, Chen MH, Chesley SR, Chiu G, Collins GS, Cox MW, DeCoster ME, Ericksen PS, Espiritu RC, Faber AS, Farnham TL, Ferrari F, Fletcher ZJ, Gaskell RW, Graninger DM, Haque MA, Harrington-Duff PA, Hefter S, Herreros I, Hirabayashi M, Huang PM, Hsieh SYW, Jacobson SA, Jenkins SN, Jensenius MA, John JW, Jutzi M, Kohout T, Krueger TO, Laipert FE, Lopez NR, Luther R, Lucchetti A, Mages DM, Marchi S, Martin AC, McQuaide ME, Michel P, Moskovitz NA, Murphy IW, Murdoch N, Naidu SP, Nair H, Nolan MC, Ormö J, Pajola M, Palmer EE, Peachey JM, Pravec P, Raducan SD, Ramesh KT, Ramirez JR, Reynolds EL, Richman JE, Robin CQ, Rodriguez LM, Roufberg LM, Rush BP, Sawyer CA, Scheeres DJ, Scheirich P, Schwartz SR, Shannon MP, Shapiro BN, Shearer CE, Smith EJ, Steele RJ, Steckloff JK, Stickle AM, Sunshine JM, Superfin EA, Tarzi ZB, Thomas CA, Thomas JR, Trigo-Rodríguez JM, Tropf BT, Vaughan AT, Velez D, Waller CD, Wilson DS, Wortman KA, Zhang Y. Successful kinetic impact into an asteroid for planetary defence. Nature 2023; 616:443-447. [PMID: 36858073 PMCID: PMC10115643 DOI: 10.1038/s41586-023-05810-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 02/08/2023] [Indexed: 03/03/2023]
Abstract
Although no known asteroid poses a threat to Earth for at least the next century, the catalogue of near-Earth asteroids is incomplete for objects whose impacts would produce regional devastation1,2. Several approaches have been proposed to potentially prevent an asteroid impact with Earth by deflecting or disrupting an asteroid1-3. A test of kinetic impact technology was identified as the highest-priority space mission related to asteroid mitigation1. NASA's Double Asteroid Redirection Test (DART) mission is a full-scale test of kinetic impact technology. The mission's target asteroid was Dimorphos, the secondary member of the S-type binary near-Earth asteroid (65803) Didymos. This binary asteroid system was chosen to enable ground-based telescopes to quantify the asteroid deflection caused by the impact of the DART spacecraft4. Although past missions have utilized impactors to investigate the properties of small bodies5,6, those earlier missions were not intended to deflect their targets and did not achieve measurable deflections. Here we report the DART spacecraft's autonomous kinetic impact into Dimorphos and reconstruct the impact event, including the timeline leading to impact, the location and nature of the DART impact site, and the size and shape of Dimorphos. The successful impact of the DART spacecraft with Dimorphos and the resulting change in the orbit of Dimorphos7 demonstrates that kinetic impactor technology is a viable technique to potentially defend Earth if necessary.
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Affiliation(s)
- R Terik Daly
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA.
| | - Carolyn M Ernst
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | | | - Nancy L Chabot
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Andrew S Rivkin
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Andrew F Cheng
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Elena Y Adams
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | | | - Elisabeth D Abel
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Amy L Alford
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | | | - Justin A Atchison
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Andrew R Badger
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Paul Baki
- Technical University of Kenya, Nairobi, Kenya
| | - Ronald-L Ballouz
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Dmitriy L Bekker
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Julie Bellerose
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - Shyam Bhaskaran
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - Bonnie J Buratti
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | | | - Michelle H Chen
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Steven R Chesley
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - George Chiu
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | | | - Matthew W Cox
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | | | - Peter S Ericksen
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | | | - Alan S Faber
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | | | | | | | | | - Dawn M Graninger
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Musad A Haque
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | | | - Sarah Hefter
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Isabel Herreros
- Centro de Astrobiologiá (CAB) CSIC-INTA, Torrejón de Ardoz, Spain
| | | | - Philip M Huang
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Syau-Yun W Hsieh
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | | | - Stephen N Jenkins
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Mark A Jensenius
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Jeremy W John
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | | | - Tomas Kohout
- Institute of Geology of the Czech Academy of Sciences, Prague, Czech Republic
- University of Helsinki, Helsinki, Finland
| | - Timothy O Krueger
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Frank E Laipert
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
- Nabla Zero Labs, South Pasadena, CA, USA
| | - Norberto R Lopez
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Robert Luther
- Museum für Naturkunde, Leibniz Institute for Evolution and Biodiversity Science, Berlin, Germany
| | | | - Declan M Mages
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | | | - Anna C Martin
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Maria E McQuaide
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Patrick Michel
- Université Côte d'Azur, Observatoire de la Côte d'Azur, CNRS, Laboratoire Lagrange, Nice, France
| | | | - Ian W Murphy
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Naomi Murdoch
- ISAE-SUPAERO, Université de Toulouse, Toulouse, France
| | - Shantanu P Naidu
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - Hari Nair
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | | | - Jens Ormö
- Centro de Astrobiologiá (CAB) CSIC-INTA, Torrejón de Ardoz, Spain
| | | | | | - James M Peachey
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Petr Pravec
- Astronomical Institute AS CR, Ondrejov, Czech Republic
| | | | - K T Ramesh
- Johns Hopkins University, Baltimore, MD, USA
| | - Joshua R Ramirez
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Edward L Reynolds
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Joshua E Richman
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Colas Q Robin
- ISAE-SUPAERO, Université de Toulouse, Toulouse, France
| | - Luis M Rodriguez
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Lew M Roufberg
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Brian P Rush
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - Carolyn A Sawyer
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | | | | | | | - Matthew P Shannon
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Brett N Shapiro
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Caitlin E Shearer
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Evan J Smith
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - R Joshua Steele
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | | | - Angela M Stickle
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | | | - Emil A Superfin
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Zahi B Tarzi
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | | | - Justin R Thomas
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | | | - B Teresa Tropf
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Andrew T Vaughan
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - Dianna Velez
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - C Dany Waller
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Daniel S Wilson
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Kristin A Wortman
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Yun Zhang
- University of Maryland, College Park, MD, USA
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Klemt C, Padmanabha A, Esposito JG, Laurencin S, Smith EJ, Kwon YM. Elevated ESR and CRP Prior to Second-Stage Reimplantation Knee Revision Surgery for Periprosthetic Joint Infection Are Associated with Increased Reinfection Rates. J Knee Surg 2023; 36:354-361. [PMID: 34375998 DOI: 10.1055/s-0041-1733902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Although two-stage revision surgery is considered as the most effective treatment for managing chronic periprosthetic joint infection (PJI), there is no current consensus on the predictors of optimal timing to second-stage reimplantation. This study aimed to compare clinical outcomes between patients with elevated erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) prior to second-stage reimplantation and those with normalized ESR and CRP prior to second-stage reimplantation. We retrospectively reviewed 198 patients treated with two-stage revision total knee arthroplasty for chronic PJI. Cohorts included patients with: (1) normal level of serum ESR and CRP (n = 96) and (2) elevated level of serum ESR and CRP prior to second-stage reimplantation (n = 102). Outcomes including reinfection rates and readmission rates were compared between both cohorts. At a mean follow-up of 4.4 years (2.8-6.5 years), the elevated ESR and CRP cohort demonstrated significantly higher reinfection rates compared with patients with normalized ESR and CRP prior to second-stage reimplantation (33.3% vs. 14.5%, p < 0.01). Patients with both elevated ESR and CRP demonstrated significantly higher reinfection rates, when compared with patients with elevated ESR and normalized CRP (33.3% vs. 27.6%, p = 0.02) as well as normalized ESR and elevated CRP (33.3% vs. 26.3%, p < 0.01). This study demonstrates that elevated serum ESR and/or CRP levels prior to reimplantation in two-stage knee revision surgery for chronic PJI are associated with increased reinfection rate after surgery. Elevation of both ESR and CRP were associated with a higher risk of reinfection compared with elevation of either ESR or CRP, suggesting the potential benefits of normalizing ESR and CRP prior to reimplantation in treatment of chronic PJI.
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Affiliation(s)
- Christian Klemt
- Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Anand Padmanabha
- Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - John G Esposito
- Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Samuel Laurencin
- Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Evan J Smith
- Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Young-Min Kwon
- Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
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Klemt C, Padmanabha A, Tirumala V, Smith EJ, Kwon YM. The Effect of Joint Line Elevation on In Vivo Knee Kinematics in Bicruciate Retaining Total Knee Arthroplasty. J Knee Surg 2022; 35:1445-1452. [PMID: 33636741 DOI: 10.1055/s-0041-1724132] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Prior studies have reported a negative effect on both clinical outcomes and patient-reported outcome measures (PROMS) following joint line elevation (JLE) in cruciate-retaining (CR) total knee arthroplasty (TKA) and posterior stabilized (PS) TKA designs. This experimental study was aimed to quantify the effect of JLE on in vivo knee kinematics in patients with bicruciate retaining (BCR) TKA during strenuous activities. Thirty unilateral BCR TKA patients were evaluated during single-leg deep lunge and sit-to-stand using a validated combined computer tomography and dual fluoroscopic imaging system. Correlation analysis was performed to quantify any correlations between JLE and in vivo kinematics, as well as PROMS. There was a significant negative correlation between JLE and maximum flexion angle during single-leg deep lunge (ρ = -0.34, p = 0.02), maximum varus joint angles during single-leg deep lunge (ρ = -0.37, p = 0.04), and sit-to-stand (ρ = -0.29, p = 0.05). There was a significant negative correlation between JLE and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score (ρ = -0.39, p = 0.01) and knee disability and osteoarthritis outcome score physical function (KOOS-PS; ρ = -0.33, p = 0.03). The JLE that yields a significant loss in PROMS and maximum flexion angles were 2.6 and 2.3 mm, respectively. There was a linear negative correlation of JLE with both in vivo knee kinematics and PROMS, with changes in JLE of greater than 2.6 and 2.3 mm, leading to a clinically significant loss in PROMS and maximum flexion angles, respectively, suggesting an increased need to improve surgical precision to optimize patient outcomes following BCR TKA.
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Affiliation(s)
- Christian Klemt
- Department of Orthopaedic Surgery, Bioengineering Laboratory, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Anand Padmanabha
- Department of Orthopaedic Surgery, Bioengineering Laboratory, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Venkatsaiakhil Tirumala
- Department of Orthopaedic Surgery, Bioengineering Laboratory, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Evan J Smith
- Department of Orthopaedic Surgery, Bioengineering Laboratory, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Young-Min Kwon
- Department of Orthopaedic Surgery, Bioengineering Laboratory, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
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5
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Klemt C, Drago J, Oganesyan R, Smith EJ, Yeo I, Kwon YM. Gait and Knee Flexion In Vivo Kinematics of Asymmetric Tibial Polyethylene Geometry Cruciate Retaining Total Knee Arthroplasty. J Knee Surg 2022; 35:828-837. [PMID: 33111271 DOI: 10.1055/s-0040-1718681] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The preservation of the posterior cruciate ligament in cruciate retaining (CR) total knee arthroplasty (TKA) designs has the potential to restore healthy knee biomechanics; however, concerns related to kinematic asymmetries during functional activities still exist in unilateral TKA patients. As there is a limited data available regarding the ability of the contemporary CR TKA design with concave medial and convex lateral tibial polyethylene bearing components to restore healthy knee biomechanics, this study aimed to investigate in vivo three-dimensional knee kinematics in CR TKA patients during strenuous knee flexion activities and gait. Using a combined computer tomography and dual fluoroscopic imaging system approach, in vivo kinematics of 15 unilateral CR TKA patients (comparison of replaced and contralateral nonreplaced knee) were evaluated during sit-to-stand, step-ups, single-leg deep lunge, and level walking. The patient cohort was followed-up at an average of 24.5 months ( ± 12.6, range 13-42) from surgical procedure. Significantly smaller internal knee rotation angles were observed for the contemporary CR TKA design during step-ups (2.6 ± 5.8 vs. 6.3 ± 6.6 degrees, p < 0.05) and gait (0.6 ± 4.6 vs. 6.3 ± 6.8 degrees, p < 0.05). Significantly larger proximal and anterior femoral translations were measured during sit-to-stand (34.7 ± 4.5 vs. 29.9 ± 3.1 mm, p < 0.05; -2.5 ± 2.9 vs. -8.1 ± 4.4 mm, p < 0.05) and step-ups (34.1 ± 4.5 vs. 30.8 ± 2.9 mm, p < 0.05; 2.2 ± 3.2 vs. -3.5 ± 4.5 mm, p < 0.05). Significantly smaller ranges of varus/valgus and internal/external rotation range of motion were observed for CR TKA, when compared with the nonoperated nee, during strenuous activities and gait. The preservation of the posterior cruciate ligament in the contemporary asymmetric bearing geometry CR TKA design with concave medial and convex lateral tibial polyethylene bearing components has the potential to restore healthy knee biomechanics; however, the study findings demonstrate that native knee kinematics were not fully restored in patients with unilateral asymmetric tibial polyethylene bearing geometry CR TKA during functional activities.
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Affiliation(s)
- Christian Klemt
- Bioengineering Laboratory, Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - John Drago
- Bioengineering Laboratory, Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Ruben Oganesyan
- Bioengineering Laboratory, Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Evan J Smith
- Bioengineering Laboratory, Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Ingwon Yeo
- Bioengineering Laboratory, Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Young-Min Kwon
- Bioengineering Laboratory, Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
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Smith EJ, Gartman EJ. The Clinical Utility of Cardiopulmonary Exercise Testing. R I Med J (2013) 2021; 104:14-19. [PMID: 34437660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Affiliation(s)
- Evan J Smith
- Division of Pulmonary, Critical Care, and Sleep Medicine, Rhode Island Hospital and The Miriam Hospital; Providence VA Medical Center; Alpert Medical School of Brown University
| | - Eric J Gartman
- Director of Pulmonary Function Testing Laboratory, Director of Cardiopulmonary Exercise Testing Laboratory, Providence VA Medical Center; Associate Professor of Medicine, Alpert Medical School of Brown University
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Klemt C, Smith EJ, Tirumala V, Bounajem G, van den Kieboom J, Kwon YM. Outcomes and Risk Factors Associated With 2-Stage Reimplantation Requiring an Interim Spacer Exchange for Periprosthetic Joint Infection. J Arthroplasty 2021; 36:1094-1100. [PMID: 33011012 DOI: 10.1016/j.arth.2020.09.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 09/01/2020] [Accepted: 09/09/2020] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND Patients undergoing a 2-stage revision for periprosthetic joint infection (PJI) often require a repeat spacer in the interim due to persistent infection. This study aims to report outcomes for patients with repeat spacer exchange and to identify risk factors associated with interim spacer exchange in 2-stage revision arthroplasty. METHODS A total of 256 consecutive 2-stage revisions for chronic infection of total hip arthroplasty and total knee arthroplasty with reimplantation and minimum 2-year follow-up were investigated. An interim spacer exchange was performed in 49 patients (exchange cohort), and these patients were propensity score matched to 196 patients (nonexchange cohort). Multivariate analysis was performed to analyze risk factors for failure of interim spacer exchange. RESULTS Patients in the propensity score-matched exchange cohort demonstrated a significantly increased reinfection risk compared to patients without interim spacer exchange (24% vs 15%, P = .03). Patients in the propensity score-matched exchange cohort showed significantly lower postoperative scores for 3 patient-reported outcome measures (PROMs): hip disability and osteoarthritis outcome score physical function (46.0 vs 54.9, P = .01); knee disability and osteoarthritis outcome score physical function (43.1 vs 51.7, P < .01); and patient-reported outcomes measurement information system physical function short form (41.6 vs 47.0, P = .03). Multivariate analysis demonstrated Charles Comorbidity Index (odds ratio, 1.56; P = .01) and the presence of Enterococcus species (odds ratio, 1.43; P = .03) as independent risk factors associated with 2-stage reimplantation requiring an interim spacer exchange for periprosthetic joint infection. CONCLUSION This study demonstrates that patients with spacer exchange had a significantly higher risk of reinfection at 2 years of follow-up. Additionally, patients with spacer exchange demonstrated lower postoperative PROM scores and diminished improvement in multiple PROM scores after reimplantation, indicating that an interim spacer exchange in 2-stage revision is associated with worse patient outcomes.
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Affiliation(s)
- Christian Klemt
- Bioengineering Laboratory, Department of Orthopaedic Surgery, Massachusetts General Hospital Harvard Medical School, Boston, MA
| | - Evan J Smith
- Bioengineering Laboratory, Department of Orthopaedic Surgery, Massachusetts General Hospital Harvard Medical School, Boston, MA
| | - Venkatsaiakhil Tirumala
- Bioengineering Laboratory, Department of Orthopaedic Surgery, Massachusetts General Hospital Harvard Medical School, Boston, MA
| | - Georges Bounajem
- Bioengineering Laboratory, Department of Orthopaedic Surgery, Massachusetts General Hospital Harvard Medical School, Boston, MA
| | - Janna van den Kieboom
- Bioengineering Laboratory, Department of Orthopaedic Surgery, Massachusetts General Hospital Harvard Medical School, Boston, MA
| | - Young-Min Kwon
- Bioengineering Laboratory, Department of Orthopaedic Surgery, Massachusetts General Hospital Harvard Medical School, Boston, MA
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8
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Klemt C, Smith EJ, Oganesyan R, Limmahakhun S, Fitz D, Kwon YM. Outcome of Dual Mobility Constructs for Adverse Local Tissue Reaction Associated Abductor Deficiency in Revision Total Hip Arthroplasty. J Arthroplasty 2020; 35:3686-3691. [PMID: 32654942 DOI: 10.1016/j.arth.2020.06.043] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 06/04/2020] [Accepted: 06/16/2020] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND Treatment of adverse local tissue reaction (ALTR) is challenging owing to high complications and poor outcomes after a revision surgery. As dislocation is the most common cause of reoperation, it is often necessary to use advanced articulations such as dual mobility. This study aims to evaluate the outcome and complication rates after revision surgery with dual mobility constructs, compared to constrained and conventional articulations in the setting of significant abductor deficiency due to ALTR. METHODS Out of a total of 338 revision total hip arthroplasties for ALTR, 234 patients with a significant tissue necrosis and abductor muscle insufficiency (grade 3) were evaluated. The complication rates after revisions were compared between 42 hips with dual mobility implants, 24 hips with constrained liners, 104 hips with large diameter heads (36-40 mm), and 64 hips with small diameter heads (≤32 mm). RESULTS After an average of 4 years of follow-up (2.8-8.6), the dual mobility articulation had no dislocation, compared to 4.1% and 15.5% for constrained liner and conventional articulations, respectively (P < .001). Utilization of dual mobility and constrained liner cup also did not increase the risk of nondislocation complications, including periprosthetic joint infection and periprosthetic fracture (P = .18 and .52). CONCLUSIONS This study demonstrates significantly lower dislocation rates for dual mobility when compared to conventional articulations and comparable to constrained liners in cases of severe abductor deficiency due to ALTR, suggesting that dual mobility implants are viable surgical treatment alternatives to constrained liners to minimize dislocation during revision total hip arthroplasty in the setting of significant abductor deficiency due to ALTR.
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Affiliation(s)
- Christian Klemt
- Bioengineering Laboratory, Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA
| | - Evan J Smith
- Bioengineering Laboratory, Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA
| | - Ruben Oganesyan
- Bioengineering Laboratory, Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA
| | - Sakkadech Limmahakhun
- Bioengineering Laboratory, Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA
| | - David Fitz
- Bioengineering Laboratory, Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA
| | - Young-Min Kwon
- Bioengineering Laboratory, Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA
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Smith EJ, Katakam A, Box HN, Healy WL, Bedair HS, Melnic CM. Staged vs Concurrent Hardware Removal During Conversion Total Knee Arthroplasty. J Arthroplasty 2020; 35:3569-3574. [PMID: 32694028 DOI: 10.1016/j.arth.2020.06.055] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 06/07/2020] [Accepted: 06/18/2020] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND Conversion total knee arthroplasty (TKA) in the presence of periarticular hardware can be associated with increased resource utilization, complications, and revisions. However, little guidance exists on the optimal approach to hardware removal. The purpose of this study is to compare outcomes of conversion TKA with hardware removal performed in either a staged or concurrent manner. METHODS This is a retrospective study of 155 TKA operations performed with staged (45) or concurrent (110) removal of hardware at the time of TKA. Differences in patient data, case data, complications, reoperations, and revisions were evaluated. Subgroup comparisons of cases involving major hardware (plates, nails, rods), minor hardware (screws, buttons, wires), and tibial plates were performed. RESULTS There were no differences in age, sex, body mass index, or comorbidities between patients who underwent staged or concurrent hardware removal. Rates of complications, reoperations, and revisions did not differ at multiple time points (90 days, 1 year, 2 years, 4 years). Patients who underwent staged hardware removal were more likely to have had prior surgery for fracture reconstruction (68% vs 33%, P < .001), to have had major hardware removed (84% vs 59%, P = .03), and were less likely to have had hardware removal performed through a single incision with TKA (50% vs 92%, P < .001). Subgroup analysis of major and minor hardware cases demonstrated comparable outcomes. CONCLUSION There remains no established benefit to either a staged or concurrent approach to hardware removal at the time of TKA. This is true regardless of hardware burden. At this time, a case-by-case approach should be taken to conversion TKA in the presence of periarticular hardware.
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Affiliation(s)
- Evan J Smith
- Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA; Department of Orthopaedic Surgery, Newton-Wellesley Hospital, Newton, MA
| | - Akhil Katakam
- Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA; Department of Orthopaedic Surgery, Newton-Wellesley Hospital, Newton, MA
| | - Hayden N Box
- Essex Orthopaedics and Sports Medicine, Salem, NH
| | - William L Healy
- Department of Orthopaedic Surgery, Lahey Hospital and Medical Center, Boston University School of Medicine, Burlington, MA
| | - Hany S Bedair
- Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA; Department of Orthopaedic Surgery, Newton-Wellesley Hospital, Newton, MA
| | - Christopher M Melnic
- Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA; Department of Orthopaedic Surgery, Newton-Wellesley Hospital, Newton, MA
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10
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McBeath KCC, Rathod KS, Cadd M, Beirne A, Guttmann O, Knight CJ, Amersey R, Bourantas CV, Wragg A, Smith EJ, Baumbach A, Mathur A, Jones DA. Use of enhanced stent visualisation compared to angiography alone to guide percutaneous coronary intervention. Int J Cardiol 2020; 321:24-29. [PMID: 32800911 DOI: 10.1016/j.ijcard.2020.08.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Revised: 07/01/2020] [Accepted: 08/07/2020] [Indexed: 12/17/2022]
Abstract
OBJECTIVE We aimed to assess the use of enhanced stent visualisation (ESV) on outcomes, after PCI with overlapping stents, specifically using CLEARstent technology. BACKGROUND Stent underexpansion and overlap are both significant risk factors for restenosis and stent thrombosis. Enhanced stent visualisation (e.g. CLEARstent) systems could provide important data to reduce under-expansion and stent overlap. METHODS This was a cohort study based on this institution's percutaneous coronary intervention (PCI) registry. A total of 2614 patients who had PCI for stable angina or acute coronary syndromes (ACS, excluding cardiogenic shock) with overlapping 2nd generation drug eluting stents (DES) in the same vessel between May 2015 and January 2018 were included in the analysis. Patients were divided into ESV (n = 1354) and no ESV guided intervention (n = 1260). The primary end-point was major adverse cardiovascular events (MACE: target vessel revascularisation, target vessel myocardial infarction and all-cause mortality) recorded at a median follow up of 2.4 years. RESULTS Groups were comparable for patient characteristics (age, diabetes mellitus, ACS presentation). A significant difference in MACE was observed between patients who underwent ESV-guided PCI (9.5%) compared with patients who underwent Standard PCI (14.4%, p = .018). This difference was mainly driven by reduced rates of target vessel revascularisation and recurrent myocardial infarction. Overall this difference persisted after multivariate Cox analysis (HR 0.86, 95% CI: 0.73-0.98) and propensity matching (HR = 0.88, 95% CI: 0.69-0.99). CONCLUSION We suggest that routine clinical use of ESV technology during PCI can be useful, and is associated with better medium-term angiographic and clinical outcomes. Further study is required to build on this promising signal.
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Affiliation(s)
- K C C McBeath
- Barts Interventional Group, Interventional Cardiology, Barts Heart Centre, St Bartholomew's Hospital, 2nd Floor, King George V Building, West Smithfield, London EC1A 7BE, United Kingdom
| | - K S Rathod
- Barts Interventional Group, Interventional Cardiology, Barts Heart Centre, St Bartholomew's Hospital, 2nd Floor, King George V Building, West Smithfield, London EC1A 7BE, United Kingdom; Centre for Cardiovascular Medicine and Devices, William Harvey Research Institute, Queen Mary University of London, United Kingdom
| | - M Cadd
- Barts Interventional Group, Interventional Cardiology, Barts Heart Centre, St Bartholomew's Hospital, 2nd Floor, King George V Building, West Smithfield, London EC1A 7BE, United Kingdom
| | - A Beirne
- Barts Interventional Group, Interventional Cardiology, Barts Heart Centre, St Bartholomew's Hospital, 2nd Floor, King George V Building, West Smithfield, London EC1A 7BE, United Kingdom; Centre for Cardiovascular Medicine and Devices, William Harvey Research Institute, Queen Mary University of London, United Kingdom
| | - O Guttmann
- Barts Interventional Group, Interventional Cardiology, Barts Heart Centre, St Bartholomew's Hospital, 2nd Floor, King George V Building, West Smithfield, London EC1A 7BE, United Kingdom
| | - C J Knight
- Barts Interventional Group, Interventional Cardiology, Barts Heart Centre, St Bartholomew's Hospital, 2nd Floor, King George V Building, West Smithfield, London EC1A 7BE, United Kingdom
| | - R Amersey
- Barts Interventional Group, Interventional Cardiology, Barts Heart Centre, St Bartholomew's Hospital, 2nd Floor, King George V Building, West Smithfield, London EC1A 7BE, United Kingdom
| | - C V Bourantas
- Barts Interventional Group, Interventional Cardiology, Barts Heart Centre, St Bartholomew's Hospital, 2nd Floor, King George V Building, West Smithfield, London EC1A 7BE, United Kingdom; Centre for Cardiovascular Medicine and Devices, William Harvey Research Institute, Queen Mary University of London, United Kingdom
| | - A Wragg
- Barts Interventional Group, Interventional Cardiology, Barts Heart Centre, St Bartholomew's Hospital, 2nd Floor, King George V Building, West Smithfield, London EC1A 7BE, United Kingdom; Centre for Cardiovascular Medicine and Devices, William Harvey Research Institute, Queen Mary University of London, United Kingdom
| | - E J Smith
- Barts Interventional Group, Interventional Cardiology, Barts Heart Centre, St Bartholomew's Hospital, 2nd Floor, King George V Building, West Smithfield, London EC1A 7BE, United Kingdom; Centre for Cardiovascular Medicine and Devices, William Harvey Research Institute, Queen Mary University of London, United Kingdom
| | - A Baumbach
- Barts Interventional Group, Interventional Cardiology, Barts Heart Centre, St Bartholomew's Hospital, 2nd Floor, King George V Building, West Smithfield, London EC1A 7BE, United Kingdom
| | - A Mathur
- Barts Interventional Group, Interventional Cardiology, Barts Heart Centre, St Bartholomew's Hospital, 2nd Floor, King George V Building, West Smithfield, London EC1A 7BE, United Kingdom; Centre for Cardiovascular Medicine and Devices, William Harvey Research Institute, Queen Mary University of London, United Kingdom
| | - D A Jones
- Barts Interventional Group, Interventional Cardiology, Barts Heart Centre, St Bartholomew's Hospital, 2nd Floor, King George V Building, West Smithfield, London EC1A 7BE, United Kingdom; Centre for Cardiovascular Medicine and Devices, William Harvey Research Institute, Queen Mary University of London, United Kingdom.
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11
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Abstract
Introduction/purpose Total knee arthroplasty (TKA) in the setting of previous periarticular hardware increases resource utilization, readmissions, complications, and revision rates. Despite the frequency of intramedullary nail (IMN) fixation for tibial fractures, little guidance exists on the management of these patients and no series have reported on outcomes of patients undergoing TKA in the setting of a retained or removed IMN. Methods This is a retrospective case series of patients who underwent TKA after IMN fixation of tibial fractures. Patient and case data, including need for hardware removal, staged vs non-staged procedures, operative time, and need for revision implants, were recorded. Postoperative data, including complications and revision, were recorded. Oxford Knee Score (OKS) was performed at follow-up. Results Nine patients were identified consisting of eight women and one man. Follow-up ranged from 0.8–13 years. Non-staged removal of the intramedullary hardware occurred in three cases that had increased operative lengths recorded. There were no complications related to wound healing or infection. No patients required revision. Two of the three patients who underwent non-staged TKA developed arthrofibrosis requiring manipulation. OKS scores in patients who underwent non-staged surgery were consistently low. Conclusions Conversion TKA after tibial IMN fixation can result in satisfying outcomes in many patients. However, intramedullary hardware presents challenges to TKA similar to more extensively studied conversion TKA scenarios. Removing hardware in either a staged or non-staged fashion results in increased resource utilization and imparts perioperative challenges with only theoretical benefits of one approach compared to the other. Increased stiffness may be associated with a non-staged approach to hardware removal and TKA. Several technical factors may permit component positioning without removal of hardware. Despite limitations, this is the first series to discuss this challenging clinical scenario and provides surgeons with technical guidance and data on operative outcomes.
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Affiliation(s)
- Evan J Smith
- Department of Orthopaedic Surgery, Massachusetts General Hospital/Newton Wellesley Hospital, Harvard Medical School, 55 Fruit Street, YAW 3700 - Suite 3B, Boston, MA, 02114, USA.
| | - Marilyn Heng
- Department of Orthopaedic Surgery, Massachusetts General Hospital/Newton Wellesley Hospital, Harvard Medical School, 55 Fruit Street, YAW 3700 - Suite 3B, Boston, MA, 02114, USA
| | - Hany S Bedair
- Department of Orthopaedic Surgery, Massachusetts General Hospital/Newton Wellesley Hospital, Harvard Medical School, 55 Fruit Street, YAW 3700 - Suite 3B, Boston, MA, 02114, USA
| | - Christopher M Melnic
- Department of Orthopaedic Surgery, Massachusetts General Hospital/Newton Wellesley Hospital, Harvard Medical School, 55 Fruit Street, YAW 3700 - Suite 3B, Boston, MA, 02114, USA
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12
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Paterson YZ, Cribbs A, Espenel M, Smith EJ, Henson FMD, Guest DJ. Genome-wide transcriptome analysis reveals equine embryonic stem cell-derived tenocytes resemble fetal, not adult tenocytes. Stem Cell Res Ther 2020; 11:184. [PMID: 32430075 PMCID: PMC7238619 DOI: 10.1186/s13287-020-01692-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 04/21/2020] [Accepted: 04/28/2020] [Indexed: 01/10/2023] Open
Abstract
Background Tendon injuries occur frequently in human and equine athletes. Treatment options are limited, and the prognosis is often poor with functionally deficient scar tissue resulting. Fetal tendon injuries in contrast are capable of healing without forming scar tissue. Embryonic stem cells (ESCs) may provide a potential cellular therapeutic to improve adult tendon regeneration; however, whether they can mimic the properties of fetal tenocytes is unknown. To this end, understanding the unique expression profile of normal adult and fetal tenocytes is crucial to allow validation of ESC-derived tenocytes as a cellular therapeutic. Methods Equine adult, fetal and ESC-derived tenocytes were cultured in a three-dimensional environment, with histological, morphological and transcriptomic differences compared. Additionally, the effects on gene expression of culturing adult and fetal tenocytes in either conventional two-dimensional monolayer culture or three-dimensional culture were compared using RNA sequencing. Results No qualitative differences in three-dimensional tendon constructs generated from adult, fetal and ESCs were found using histological and morphological analysis. However, genome-wide transcriptomic analysis using RNA sequencing revealed that ESC-derived tenocytes’ transcriptomic profile more closely resembled fetal tenocytes as opposed to adult tenocytes. Furthermore, this study adds to the growing evidence that monolayer cultured cells’ gene expression profiles converge, with adult and fetal tenocytes having only 10 significantly different genes when cultured in this manner. In contrast, when adult and fetal tenocytes were cultured in 3D, large distinctions in gene expression between these two developmental stages were found, with 542 genes being differentially expressed. Conclusion The information provided in this study makes a significant contribution to the investigation into the differences between adult reparative and fetal regenerative cells and supports the concept of using ESC-derived tenocytes as a cellular therapy. Comparing two- and three-dimensional culture also indicates three-dimensional culture as being a more physiologically relevant culture system for determining transcriptomic difference between the same cell types from different developmental stages.
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Affiliation(s)
- Y Z Paterson
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge, CB3 0ES, UK. .,Centre for Preventive Medicine, Animal Health Trust, Lanwades Park, Kentford, Newmarket, Suffolk, CB8 7UU, UK.
| | - A Cribbs
- Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, OX3 7LD, UK
| | - M Espenel
- Centre for Preventive Medicine, Animal Health Trust, Lanwades Park, Kentford, Newmarket, Suffolk, CB8 7UU, UK
| | - E J Smith
- Centre for Preventive Medicine, Animal Health Trust, Lanwades Park, Kentford, Newmarket, Suffolk, CB8 7UU, UK
| | - F M D Henson
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge, CB3 0ES, UK.,Centre for Preventive Medicine, Animal Health Trust, Lanwades Park, Kentford, Newmarket, Suffolk, CB8 7UU, UK
| | - D J Guest
- Centre for Preventive Medicine, Animal Health Trust, Lanwades Park, Kentford, Newmarket, Suffolk, CB8 7UU, UK
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13
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Beirne A, Rathod K, Jain A, Mathur A, Wragg A, Smith EJ, Jones DA, Kalra S, Malik I, Redwood S, MacCarthy P, Bogle R, Firoozi S, Dalby M. P6516The association between prior coronary artery bypass graft surgery and outcome after percutaneous coronary intervention (PCI): an observational study of 123,780 patients. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz746.1106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Background
Limited information exists regarding procedural success and clinical outcomes in patients with previous CABG undergoing percutaneous coronary intervention (PCI). We sought to compare outcomes in patients undergoing PCI with or without previous coronary artery bypass grafts (CABG).
Methods
This was an observational cohort study of 123,780 consecutive PCI procedures from the Pan-London (United Kingdom) PCI registry, from January 2005 to December 2015. The primary end-point was all-cause mortality at a median follow-up of 3.0 years (interquartile range 1.2–4.6 years).
Results
12,641 (10.2%) patients had a history of previous CABG, of whom 29.3% (n=3,703) underwent PCI to native vessels and 70.7% (n=8,938) to bypass grafts. There were significant differences in the demographic, clinical, and procedural characteristics of these groups. The risk of mortality during follow-up was significantly higher in patients with prior CABG (23.2%) (p=0.0005) compared to patients with no history of prior CABG (12.1%) and was seen for patients who underwent either native vessel (20.1%) or bypass graft PCI (24.2%, p<0.0001). However, after adjustment for baseline characteristics, there was no significant difference in outcomes seen between the groups when PCI was performed in native vessels in patients with previous CABG (HR 1.02, 95% CI 0.77–1.34; P=0.89) but a significant increase in mortality among patients with PCI to bypass grafts (HR 1.33 95% CI 1.03–1.71, P=0.026). This was seen after multivariate adjustment and propensity matching.
Figure 1. Kaplan-Meier Curves
Conclusion
Patients with prior CABG are older, with a greater comorbid burden and more complex procedural characteristics, but after adjustment for these differences clinical outcomes are similar to patients undergoing PCI without prior CABG. In these patients, native vessel PCI was associated with better outcomes compared to the treatment of vein grafts.
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Affiliation(s)
- A Beirne
- Barts Health NHS Trust, London, United Kingdom
| | - K Rathod
- Barts Health NHS Trust, London, United Kingdom
| | - A Jain
- Barts Health NHS Trust, London, United Kingdom
| | - A Mathur
- Barts Health NHS Trust, London, United Kingdom
| | - A Wragg
- Barts Health NHS Trust, London, United Kingdom
| | - E J Smith
- Barts Health NHS Trust, London, United Kingdom
| | - D A Jones
- Barts Health NHS Trust, London, United Kingdom
| | - S Kalra
- Royal Free Hospital, London, United Kingdom
| | - I Malik
- Imperial College Healthcare NHS Trust, London, United Kingdom
| | - S Redwood
- St Thomas' Hospital, London, United Kingdom
| | - P MacCarthy
- Kings College Hospital, London, United Kingdom
| | - R Bogle
- St Georges Hospital, London, United Kingdom
| | - S Firoozi
- St Georges Hospital, London, United Kingdom
| | - M Dalby
- Harefield Hospital, London, United Kingdom
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14
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Neupert SD, Bellingtier JA, Smith EJ. DAILY FLUCTUATIONS AND INDIVIDUAL DIFFERENCES IN CONTROL BELIEFS PREDICT PERCEPTIONS OF AGING. Innov Aging 2018. [DOI: 10.1093/geroni/igy023.253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- S D Neupert
- North Carolina State University, Raleigh, North Carolina, United States
| | | | - E J Smith
- North Carolina State University, Raleigh, NC, USA
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15
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Samways JW, Rathod KS, Guttmann O, Wragg A, Baumbach A, Weerackody R, Smith EJ, Mathur A, Amersey RA, Jones DA. P1665Outcomes and risk factors for recurrent restenosis in patients treated for coronary in-stent restenosis. Eur Heart J 2018. [DOI: 10.1093/eurheartj/ehy565.p1665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- J W Samways
- Barts Health NHS Trust, Barts Heart Centre, London, United Kingdom
| | - K S Rathod
- Barts Health NHS Trust, Barts Heart Centre, London, United Kingdom
| | - O Guttmann
- Barts Health NHS Trust, Barts Heart Centre, London, United Kingdom
| | - A Wragg
- Barts Health NHS Trust, Barts Heart Centre, London, United Kingdom
| | - A Baumbach
- Barts Health NHS Trust, Barts Heart Centre, London, United Kingdom
| | - R Weerackody
- Barts Health NHS Trust, Barts Heart Centre, London, United Kingdom
| | - E J Smith
- Barts Health NHS Trust, Barts Heart Centre, London, United Kingdom
| | - A Mathur
- Barts Health NHS Trust, Barts Heart Centre, London, United Kingdom
| | - R A Amersey
- Barts Health NHS Trust, Barts Heart Centre, London, United Kingdom
| | - D A Jones
- Barts Health NHS Trust, Barts Heart Centre, London, United Kingdom
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16
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Unger A, Smith EJ. Editorial on “No correlation between serum markers and early functional outcome after contemporary THA”. Ann Joint 2018. [DOI: 10.21037/aoj.2018.03.03] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Connerney JEP, Adriani A, Allegrini F, Bagenal F, Bolton SJ, Bonfond B, Cowley SWH, Gerard JC, Gladstone GR, Grodent D, Hospodarsky G, Jorgensen JL, Kurth WS, Levin SM, Mauk B, McComas DJ, Mura A, Paranicas C, Smith EJ, Thorne RM, Valek P, Waite J. Jupiter's magnetosphere and aurorae observed by the Juno spacecraft during its first polar orbits. Science 2018; 356:826-832. [PMID: 28546207 DOI: 10.1126/science.aam5928] [Citation(s) in RCA: 94] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 04/20/2017] [Indexed: 11/02/2022]
Abstract
The Juno spacecraft acquired direct observations of the jovian magnetosphere and auroral emissions from a vantage point above the poles. Juno's capture orbit spanned the jovian magnetosphere from bow shock to the planet, providing magnetic field, charged particle, and wave phenomena context for Juno's passage over the poles and traverse of Jupiter's hazardous inner radiation belts. Juno's energetic particle and plasma detectors measured electrons precipitating in the polar regions, exciting intense aurorae, observed simultaneously by the ultraviolet and infrared imaging spectrographs. Juno transited beneath the most intense parts of the radiation belts, passed about 4000 kilometers above the cloud tops at closest approach, well inside the jovian rings, and recorded the electrical signatures of high-velocity impacts with small particles as it traversed the equator.
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Affiliation(s)
- J E P Connerney
- Space Research Corporation, Annapolis, MD 21403, USA. .,NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - A Adriani
- Institute for Space Astrophysics and Planetology, National Institute for Astrophysics, Rome, 00133, Italy
| | - F Allegrini
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - F Bagenal
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80303, USA
| | - S J Bolton
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - B Bonfond
- Institut d'Astrophysique et de Geophysique, Universite de Liege, Liege, B-4000 Belgium
| | | | - J-C Gerard
- Institut d'Astrophysique et de Geophysique, Universite de Liege, Liege, B-4000 Belgium
| | - G R Gladstone
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - D Grodent
- Institut d'Astrophysique et de Geophysique, Universite de Liege, Liege, B-4000 Belgium
| | | | - J L Jorgensen
- National Space Institute, Technical University of Denmark, Kongens Lyngby, 2800, Denmark
| | - W S Kurth
- University of Iowa, Iowa City, IA 52242, USA
| | - S M Levin
- Jet Propulsion Laboratory/California Institute of Technology, Pasadena, CA 91109, USA
| | - B Mauk
- Johns Hopkins University, Applied Physics Laboratory, Laurel, MD 20723, USA
| | - D J McComas
- Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544, USA
| | - A Mura
- Institute for Space Astrophysics and Planetology, National Institute for Astrophysics, Rome, 00133, Italy
| | - C Paranicas
- Johns Hopkins University, Applied Physics Laboratory, Laurel, MD 20723, USA
| | - E J Smith
- Jet Propulsion Laboratory/California Institute of Technology, Pasadena, CA 91109, USA
| | - R M Thorne
- Department of Atmospheric and Oceanic Sciences, University of California-Los Angeles, Los Angeles, CA 90095, USA
| | - P Valek
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - J Waite
- Southwest Research Institute, San Antonio, TX 78238, USA
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18
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Smith EJ, Kyhos J, Dolitsky R, Yu W, O'Brien J. S2 Alar Iliac Fixation in Long Segment Constructs, a Two- to Five-Year Follow-up. Spine Deform 2018; 6:72-78. [PMID: 29287821 DOI: 10.1016/j.jspd.2017.05.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 04/18/2017] [Accepted: 05/21/2017] [Indexed: 11/17/2022]
Abstract
STUDY DESIGN Retrospective review of patients having undergone S2 alar-iliac (S2AI) fixation for long fusions with a minimum two-year follow-up. OBJECTIVES To report on fusion rates, complications, technique-specific complications of patients having undergone S2AI fixation. SUMMARY OF BACKGROUND DATA Sacropelvic fixation continues to be a challenge when performing long fusions to the pelvis. S2AI screws have been found to provide solid biomechanical fixation and have been found to have good clinical results in short-term follow-up for pediatric and adult patients. METHODS Cases were retrospectively reviewed in patients who had placement of S2AI screws for long fusions with at least a two-year follow-up. Demographic data, complications, and reoperations were reviewed. Complications were broken into minor and major categories similar to previous series on pelvic fixation. RESULTS There were 86 cases identified. Minor and major complications occurred in 29% and 24% of patients, respectively, with the majority of minor complications being intraoperative dural tears. Revision surgery for all causes was performed in 23% of the cohort. Fusion rate at L5-S1 for patients without preoperative pseudarthrosis was 95.3%. Preoperative L5-S1 pseudoarthrosis was identified in 20 patients, 17 (95%) of these went onto fusion after one surgery. There was evidence of S2AI screw lucency in 10.4% of cases. However, the majority of these were asymptomatic. CONCLUSIONS Sacropelvic fixation using the S2AI technique provides safe, durable fixation with low rates of technique-specific complications and limited need for hardware removal. Complication rates in this series were similar to other series on long fusions to the pelvis. Additionally, fusion rates were high at L5-S1 for both patients with and without preoperative L5-S1 pseudarthrosis. It appears that the S2AI technique is a powerful option for patients with previous L5-S1 pseudarthrosis. LEVEL OF EVIDENCE Level III.
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Affiliation(s)
- Evan J Smith
- Department of Orthopedic Surgery, George Washington University, 2300 M St. NW 5th Fl., Washington, DC 20037, USA.
| | - Justin Kyhos
- Department of Orthopedic Surgery, Northwestern University, 633 Clark St, Evanston, IL 60208, USA
| | - Robert Dolitsky
- Department of Orthopedic Surgery, Northwell Health, Great Neck, NY, USA
| | - Warren Yu
- Department of Orthopedic Surgery, George Washington University, 2300 M St. NW 5th Fl., Washington, DC 20037, USA
| | - Joseph O'Brien
- Department of Orthopedic Surgery, George Washington University, 2300 M St. NW 5th Fl., Washington, DC 20037, USA
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19
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Rathod KS, Antoniou S, Avari P, Ding N, Wright P, Knight C, Jain AK, Mathur A, Smith EJ, Weerackody R, Wragg A, Jones DA. Eptifibatide is associated with significant cost savings and similar clinical outcomes to abciximab when used during primary percutaneous coronary intervention for ST-elevation myocardial infarction: An observational cohort study of 3863 patients. JRSM Cardiovasc Dis 2017; 6:2048004017734431. [PMID: 29051816 PMCID: PMC5637964 DOI: 10.1177/2048004017734431] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Revised: 09/03/2017] [Accepted: 09/04/2017] [Indexed: 12/12/2022] Open
Abstract
INTRODUCTION Glycoprotein IIb/IIIa inhibitors are recommended by guidelines in patients with ST-segment elevation myocardial infarction treated with primary percutaneous coronary intervention. There are few studies directly comparing these agents. The aim of this study was to assess whether eptifibatide is a safe and cost-effective alternative to abciximab in the treatment of primary percutaneous coronary intervention for ST-segment elevation myocardial infarction. METHODS This was an observational cohort study of 3863 patients who received a GPIIb/IIIa inhibitor whilst undergoing primary percutaneous coronary intervention from 2007 to 2014. Patients who did not receive a GPIIb/IIIa inhibitor were excluded. Time to first major adverse cardiac event defined as death, non-fatal myocardial infarction, stroke or target vessel revascularization, and total hospital costs were compared between the groups. RESULTS In all, 1741 patients received abciximab with 2122 receiving eptifibatide. Patients who received eptifibatide had higher rates of previous MI/percutaneous coronary intervention and were more likely to undergo a procedure from the radial route. Unadjusted Kaplan-Meier analysis revealed no significant difference in the 1-year event rates between patients given eptifibatide versus abciximab (p = 0.201). Age-adjusted Cox analysis demonstrated no difference in 1-year outcome between abciximab and eptifibatide (hazard ratio: 0.83; 95% confidence interval: 0.73-1.39), which persisted after multivariate adjustment (hazard ratio: 0.92; 95% confidence interval: 0.79-1.56) including the incorporation of a propensity score (hazard ratio: 0.88; 95% confidence interval: 0.71-1.44). Eptifbatide was associated with significant cost savings being 87% cheaper overall compared to abciximab (on average £650 cheaper per patient and saving approximately £950,000). CONCLUSION This observational data suggest that eptifibatide is associated with similar outcomes and significant cost savings compared to abciximab when used in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention.
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Affiliation(s)
- K S Rathod
- Department of Cardiology, Barts Health NHS Trust, London, UK.,Department of Clinical Pharmacology, Queen Mary University, London, UK.,NIHR Cardiovascular Biomedical Research Centre, Barts Health NHS Trust, London, UK
| | - S Antoniou
- Department of Cardiology, Barts Health NHS Trust, London, UK.,Department of Pharmacy, Barts Health NHS Trust, London, UK
| | - P Avari
- Department of Cardiology, Barts Health NHS Trust, London, UK
| | - N Ding
- Department of Cardiology, Barts Health NHS Trust, London, UK
| | - P Wright
- Department of Cardiology, Barts Health NHS Trust, London, UK.,Department of Pharmacy, Barts Health NHS Trust, London, UK
| | - C Knight
- Department of Cardiology, Barts Health NHS Trust, London, UK.,NIHR Cardiovascular Biomedical Research Centre, Barts Health NHS Trust, London, UK
| | - A K Jain
- Department of Cardiology, Barts Health NHS Trust, London, UK.,NIHR Cardiovascular Biomedical Research Centre, Barts Health NHS Trust, London, UK
| | - A Mathur
- Department of Cardiology, Barts Health NHS Trust, London, UK.,Department of Clinical Pharmacology, Queen Mary University, London, UK.,NIHR Cardiovascular Biomedical Research Centre, Barts Health NHS Trust, London, UK
| | - E J Smith
- Department of Cardiology, Barts Health NHS Trust, London, UK.,NIHR Cardiovascular Biomedical Research Centre, Barts Health NHS Trust, London, UK
| | - R Weerackody
- Department of Cardiology, Barts Health NHS Trust, London, UK.,NIHR Cardiovascular Biomedical Research Centre, Barts Health NHS Trust, London, UK
| | - A Wragg
- Department of Cardiology, Barts Health NHS Trust, London, UK.,Department of Clinical Pharmacology, Queen Mary University, London, UK.,NIHR Cardiovascular Biomedical Research Centre, Barts Health NHS Trust, London, UK
| | - D A Jones
- Department of Cardiology, Barts Health NHS Trust, London, UK.,Department of Clinical Pharmacology, Queen Mary University, London, UK.,NIHR Cardiovascular Biomedical Research Centre, Barts Health NHS Trust, London, UK
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Smith EJ, Kuang X, Pandarinath R. Comparing hospital outcomes between open and closed tibia fractures treated with intramedullary fixation. Injury 2017; 48:1609-1612. [PMID: 28438417 DOI: 10.1016/j.injury.2017.03.038] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Accepted: 03/28/2017] [Indexed: 02/02/2023]
Abstract
INTRODUCTION Tibial shaft fractures comprise a large portion of operatively treated long bone fractures, and present with the highest rate of open injuries. Intramedullary fixation has become the standard of care for both open and closed injuries. The rates of short term complications and hospital length of stay for open and closed fractures treated with intramedullary fixation is not fully known. Previous series on tibia fractures were performed at high volume centers, and data were not generalizable, further they did not report on length of stay and the impact of preoperative variables on infections, complications and reoperation. We used a large surgical database to compare these outcomes while adjusting for preoperative risk factors. METHODS Data were extracted from the ACS-NSQIP database from 2005 to 2014. Cases were identified based on CPT codes for intramedullary fixation and categorized as closed vs open based on ICD9 code. In addition to demographic and case data, primary analysis examined correlation between open and closed fracture status with infection, complications, reoperation and hospital length of stay. Secondary analysis examined preoperative variables including gender, race, age, BMI, and diabetes effect on outcomes. RESULTS There were 272 cases identified. There were no significant demographic differences between open and closed tibia fracture cases. Open fracture status did not increase the rate of infection, 30day complications, reoperation, or length of stay. The only preoperative factor that correlated with length of stay was age. There was no correlation between BMI, presence of insulin dependent and nondependent diabetes, and any outcome measure. DISCUSSION When considering the complication rates for open and closed tibial shaft fractures treated with intramedullary fixation, there is no difference between 30-day complication rate, length of stay, or return to the operating room. Our reported postoperative infection rates were comparable to previous series, adding validity to our results. The heterogeneity of the hospitals included in ACS-NSQIP database allow our data to be generalizable. These methods may underrepresent the true occurrence of infection as operatively treated tibia infections may present late, requiring late revision. Despite limitations, the data reflect on the current burden of managing these once devastating injuries.
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Affiliation(s)
- Evan J Smith
- The George Washington University Department of Orthopedics.
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St Charles JL, Bell JA, Gadsden BJ, Malik A, Cooke H, Van de Grift LK, Kim HY, Smith EJ, Mansfield LS. Guillain Barré Syndrome is induced in Non-Obese Diabetic (NOD) mice following Campylobacter jejuni infection and is exacerbated by antibiotics. J Autoimmun 2016; 77:11-38. [PMID: 27939129 DOI: 10.1016/j.jaut.2016.09.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Revised: 08/25/2016] [Accepted: 09/04/2016] [Indexed: 01/10/2023]
Abstract
Campylobacter jejuni is a leading cause of bacterial gastroenteritis linked to several serious autoimmune sequelae such as the peripheral neuropathies Guillain Barré syndrome (GBS) and Miller Fisher syndrome (MFS). We hypothesized that GBS and MFS can result in NOD wild type (WT) mice or their congenic interleukin (IL)-10 or B7-2 knockouts secondary to C. jejuni infection. Mice were gavaged orally with C. jejuni strains HB93-13 and 260.94 from patients with GBS or CF93-6 from a patient with MFS and assessed for clinical neurological signs and phenotypes, anti-ganglioside antibodies, and cellular infiltrates and lesions in gut and peripheral nerve tissues. Significant increases in autoantibodies against single gangliosides (GM1, GQ1b, GD1a) occurred in infected NOD mice of all genotypes, although the isotypes varied (NOD WT had IgG1, IgG3; NOD B7-2-/- had IgG3; NOD IL-10-/- had IgG1, IgG3, IgG2a). Infected NOD WT and NOD IL-10-/- mice also produced anti-ganglioside antibodies of the IgG1 isotype directed against a mixture of GM1/GQ1b gangliosides. Phenotypic tests showed significant differences between treatment groups of all mouse genotypes. Peripheral nerve lesions with macrophage infiltrates were significantly increased in infected mice of NOD WT and IL-10-/- genotypes compared to sham-inoculated controls, while lesions with T cell infiltrates were significantly increased in infected mice of the NOD B7-2-/- genotype compared to sham-inoculated controls. In both infected and sham inoculated NOD IL-10-/- mice, antibiotic treatment exacerbated neurological signs, lesions and the amount and number of different isotypes of antiganglioside autoantibodies produced. Thus, inducible mouse models of post-C. jejuni GBS are feasible and can be characterized based on evaluation of three factors-onset of GBS clinical signs/phenotypes, anti-ganglioside autoantibodies and nerve lesions. Based on these factors we characterized 1) NOD B-7-/- mice as an acute inflammatory demyelinating polyneuropathy (AIDP)-like model, 2) NOD IL-10-/- mice as an acute motor axonal neuropathy (AMAN)-like model best employed over a limited time frame, and 3) NOD WT mice as an AMAN model with mild clinical signs and lesions. Taken together these data demonstrate that C. jejuni strain genotype, host genotype and antibiotic treatment affect GBS disease outcomes in mice and that many disease phenotypes are possible.
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Affiliation(s)
- J L St Charles
- Comparative Enteric Diseases Laboratory, Michigan State University, East Lansing, MI 48824, USA; Comparative Medicine and Integrative Biology Graduate Program, Michigan State University, East Lansing, MI 48824, USA; College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824, USA
| | - J A Bell
- Comparative Enteric Diseases Laboratory, Michigan State University, East Lansing, MI 48824, USA; College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824, USA
| | - B J Gadsden
- Comparative Enteric Diseases Laboratory, Michigan State University, East Lansing, MI 48824, USA; Comparative Medicine and Integrative Biology Graduate Program, Michigan State University, East Lansing, MI 48824, USA; College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824, USA
| | - A Malik
- Comparative Enteric Diseases Laboratory, Michigan State University, East Lansing, MI 48824, USA; Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI 48824, USA; College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824, USA
| | - H Cooke
- College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824, USA
| | - L K Van de Grift
- College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824, USA
| | - H Y Kim
- Comparative Enteric Diseases Laboratory, Michigan State University, East Lansing, MI 48824, USA
| | - E J Smith
- Comparative Enteric Diseases Laboratory, Michigan State University, East Lansing, MI 48824, USA; College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824, USA
| | - L S Mansfield
- Comparative Enteric Diseases Laboratory, Michigan State University, East Lansing, MI 48824, USA; Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI 48824, USA; College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824, USA.
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Karrasch CK, Smith EJ, Armstrong AD. Distal humerus articular malunion after an open reduction-internal fixation of a capitellum-trochlea shear fracture: a case report. J Shoulder Elbow Surg 2016; 25:e55-60. [PMID: 26927435 DOI: 10.1016/j.jse.2015.12.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Revised: 12/07/2015] [Accepted: 12/14/2015] [Indexed: 02/01/2023]
Affiliation(s)
- Chris K Karrasch
- Department of Orthopeadics, Penn State Milton S. Hershey Medical Center, Hershey, PA, USA
| | - Evan J Smith
- Department of Orthopaedics, George Washington University, Washington, DC, USA
| | - April D Armstrong
- Department of Orthopeadics, Penn State Milton S. Hershey Medical Center, Hershey, PA, USA.
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Gallagher SM, Lovell MJ, Jones DA, Ferguson E, Ahktar A, Buckhoree Z, Wragg A, Knight CJ, Mathur A, Smith EJ, Cliffe S, Archbold RA, Rothman MT, Jain AK. Does a 'direct' transfer protocol reduce time to coronary angiography for patients with non-ST-elevation acute coronary syndromes? A prospective observational study. BMJ Open 2014; 4:e005525. [PMID: 25270854 PMCID: PMC4179416 DOI: 10.1136/bmjopen-2014-005525] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
OBJECTIVE National guidelines recommend 'early' coronary angiography within 96 h of presentation for patients with non-ST elevation acute coronary syndromes (NSTE-ACS). Most patients with NSTE-ACS present to their district general hospital (DGH), and await transfer to the regional cardiac centre for angiography. This care model has inherent time delays, and delivery of timely angiography is problematic. The objective of this study was to assess a novel clinical care pathway for the management of NSTE-ACS, known locally as the Heart Attack Centre-Extension or HAC-X, designed to rapidly identify patients with NSTE-ACS while in DGH emergency departments (ED) and facilitate transfer to the regional interventional centre for 'early' coronary angiography. METHODS This was an observational study of 702 patients divided into two groups; 391 patients treated before the instigation of the HAC-X pathway (Pre-HAC-X), and 311 patients treated via the novel pathway (Post-HAC-X). Our primary study end point was time from ED admission to coronary angiography. We also assessed the length of hospital stay. RESULTS Median time from ED admission to coronary angiography was 7.2 (IQR 5.1-10.2) days pre-HAC-X compared to 1.0 (IQR 0.7-2.0) day post-HAC-X (p<0.001). Median length of hospital stay was 3.0 (IQR 2.0-6.0) days post-HAC-X v 9.0 (IQR 6.0-14.0) days pre-HAC-X (p<0.0005). This equates to a reduction of six hospital bed days per NSTE-ACS admission. CONCLUSIONS The introduction of this novel care pathway was associated with significant reductions in time to angiography and in total hospital bed occupancy for patients with NSTE-ACS.
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Affiliation(s)
- S M Gallagher
- Department of Cardiology, Barts Health NHS Trust, London, UK NIHR Cardiovascular Biomedical Research Unit, London Chest Hospital, London, UK Department of Translational Medicine and Therapeutics, William Harvey Research, Queen Mary College, London, UK
| | - M J Lovell
- Department of Cardiology, Barts Health NHS Trust, London, UK
| | - D A Jones
- Department of Cardiology, Barts Health NHS Trust, London, UK NIHR Cardiovascular Biomedical Research Unit, London Chest Hospital, London, UK Department of Clinical Pharmacology, William Harvey Research Institute, Queen Mary College, London, UK
| | - E Ferguson
- Department of Cardiology, Barts Health NHS Trust, London, UK
| | - A Ahktar
- Department of Cardiology, Barts Health NHS Trust, London, UK
| | - Z Buckhoree
- Department of Cardiology, Barts Health NHS Trust, London, UK
| | - A Wragg
- Department of Cardiology, Barts Health NHS Trust, London, UK NIHR Cardiovascular Biomedical Research Unit, London Chest Hospital, London, UK
| | - C J Knight
- Department of Cardiology, Barts Health NHS Trust, London, UK NIHR Cardiovascular Biomedical Research Unit, London Chest Hospital, London, UK
| | - A Mathur
- Department of Cardiology, Barts Health NHS Trust, London, UK NIHR Cardiovascular Biomedical Research Unit, London Chest Hospital, London, UK Department of Clinical Pharmacology, William Harvey Research Institute, Queen Mary College, London, UK
| | - E J Smith
- Department of Cardiology, Barts Health NHS Trust, London, UK NIHR Cardiovascular Biomedical Research Unit, London Chest Hospital, London, UK
| | - S Cliffe
- Department of Cardiology, Barts Health NHS Trust, London, UK
| | - R A Archbold
- Department of Cardiology, Barts Health NHS Trust, London, UK NIHR Cardiovascular Biomedical Research Unit, London Chest Hospital, London, UK
| | - M T Rothman
- Department of Cardiology, Barts Health NHS Trust, London, UK
| | - A K Jain
- Department of Cardiology, Barts Health NHS Trust, London, UK NIHR Cardiovascular Biomedical Research Unit, London Chest Hospital, London, UK
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Detloff MR, Smith EJ, Quiros Molina D, Ganzer PD, Houlé JD. Acute exercise prevents the development of neuropathic pain and the sprouting of non-peptidergic (GDNF- and artemin-responsive) c-fibers after spinal cord injury. Exp Neurol 2014; 255:38-48. [PMID: 24560714 PMCID: PMC4036591 DOI: 10.1016/j.expneurol.2014.02.013] [Citation(s) in RCA: 96] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Revised: 01/29/2014] [Accepted: 02/14/2014] [Indexed: 11/18/2022]
Abstract
Spinal cord injury (SCI) impaired sensory fiber transmission leads to chronic, debilitating neuropathic pain. Sensory afferents are responsive to neurotrophic factors, molecules that are known to promote survival and maintenance of neurons, and regulate sensory neuron transduction of peripheral stimuli. A subset of primary afferent fibers responds only to the glial cell-line derived neurotrophic factor (GDNF) family of ligands (GFLs) and is non-peptidergic. In peripheral nerve injury models, restoration of GDNF or artemin (another GFL) to pre-injury levels within the spinal cord attenuates neuropathic pain. One non-invasive approach to increase the levels of GFLs in the spinal cord is through exercise (Ex), and to date exercise training is the only ameliorative, non-pharmacological treatment for SCI-induced neuropathic pain. The purpose of this study was 3-fold: 1) to determine whether exercise affects the onset of SCI-induced neuropathic pain; 2) to examine the temporal profile of GDNF and artemin in the dorsal root ganglia and spinal cord dorsal horn regions associated with forepaw dermatomes after SCI and Ex; and 3) to characterize GFL-responsive sensory fiber plasticity after SCI and Ex. Adult, female, Sprague-Dawley rats received a moderate, unilateral spinal cord contusion at C5. A subset of rats was exercised (SCI+Ex) on automated running wheels for 20min, 5days/week starting at 5days post-injury (dpi), continuing until 9 or 37dpi. Hargreaves' and von Frey testing was performed preoperatively and weekly post-SCI. Forty-two percent of rats in the unexercised group exhibited tactile allodynia of the forepaws while the other 58% retained normal sensation. The development of SCI-induced neuropathic pain correlated with a marked decrease in the levels of GDNF and artemin in the spinal cord and DRGs. Additionally, a dramatic increase in the density and the distribution throughout the dorsal horn of GFL-responsive afferents was observed in rats with SCI-induced allodynia. Importantly, in SCI rats that received Ex, the incidence of tactile allodynia decreased to 7% (1/17) and there was maintenance of GDNF and artemin at normal levels, with a normal distribution of GFL-responsive fibers. These data suggest that GFLs and/or their downstream effectors may be important modulators of pain fiber plasticity, representing effective targets for anti-allodynic therapeutics. Furthermore, we highlight the potent beneficial effects of acute exercise after SCI.
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Affiliation(s)
- Megan Ryan Detloff
- Department of Neurobiology and Anatomy, Spinal Cord Research Center, Drexel University College of Medicine, Philadelphia, PA 19129, USA.
| | - Evan J Smith
- Department of Neurobiology and Anatomy, Spinal Cord Research Center, Drexel University College of Medicine, Philadelphia, PA 19129, USA
| | - Daniel Quiros Molina
- Department of Neurobiology and Anatomy, Spinal Cord Research Center, Drexel University College of Medicine, Philadelphia, PA 19129, USA
| | - Patrick D Ganzer
- Department of Neurobiology and Anatomy, Spinal Cord Research Center, Drexel University College of Medicine, Philadelphia, PA 19129, USA
| | - John D Houlé
- Department of Neurobiology and Anatomy, Spinal Cord Research Center, Drexel University College of Medicine, Philadelphia, PA 19129, USA
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Antoniades G, Smith EJ, Deakin AH, Wearing SC, Sarungi M. Primary stability of two uncementedacetabular components of different geometry: hemispherical or peripherallyenhanced? Bone Joint Res 2013; 2:264-9. [PMID: 24326398 PMCID: PMC3860168 DOI: 10.1302/2046-3758.212.2000193] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Objective This study compared the primary stability of two commercially
available acetabular components from the same manufacturer, which
differ only in geometry; a hemispherical and a peripherally enhanced
design (peripheral self-locking (PSL)). The objective was to determine
whether altered geometry resulted in better primary stability. Methods Acetabular components were seated with 0.8 mm to 2 mm interference
fits in reamed polyethylene bone substrate of two different densities
(0.22 g/cm3 and 0.45 g/cm3). The primary stability
of each component design was investigated by measuring the peak
failure load during uniaxial pull-out and tangential lever-out tests. Results There was no statistically significant difference in seating
force (p = 0.104) or primary stability (pull-out p = 0.171, lever-out
p = 0.087) of the two components in the low-density substrate. Similarly,
in the high-density substrate, there was no statistically significant
difference in the peak pull-out force (p = 0.154) or lever-out moment
(p = 0.574) between the designs. However, the PSL component required
a significantly higher seating force than the hemispherical cup
in the high-density bone analogue (p = 0.006). Conclusions Higher seating forces associated with the PSL design may result
in inadequate seating and increased risk of component malpositioning
or acetabular fracture in the intra-operative setting in high-density
bone stock. Our results, if translated clinically, suggest that
a purely hemispherical geometry may have an advantage over a peripherally
enhanced geometry in high density bone stock. Cite this article: Bone Joint Res 2013;2:264–9.
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Affiliation(s)
- G Antoniades
- Golden Jubilee National Hospital, Departmentof Orthopaedics, Agamemnon Street, Clydebank, WestDunbartonshire G81 4DY, UK
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Zakani S, Venne G, Smith EJ, Bicknell R, Ellis RE. Analyzing shoulder translation with navigation technology. Int J Comput Assist Radiol Surg 2012; 7:853-60. [PMID: 22855410 DOI: 10.1007/s11548-012-0782-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2012] [Accepted: 07/03/2012] [Indexed: 11/30/2022]
Abstract
PURPOSE Asymmetric stress imposed on the shoulder can lead to anterior shoulder instability in young athletes who perform repetitive overhead motions. A common treatment, surgical anterior capsule tightening, assumes that the instability is caused by abnormal anterior laxity. This study investigated the possibility that one element of overall imbalance, posterior capsular tightness, could be an underlying reason for shoulder instability. Surgical navigation technology, which is more accurate than whole-body motion-capture systems, was used to study anterior translational motions. METHOD The study was used four cadaver shoulders, with the scapula and rotator cuff muscles intact. Opto-electronic surgical navigation localization devices were mounted on the scapula and humerus to accurately capture positions and orientations. The shoulders were passively moved through 7 motions, 5 of simple angulation and 2 combinations of clinical interest. Each motion was repeated in 4 different soft-tissue states: rotator cuff intact, capsule intact, and surgically induced capsular tightnesses of 5 and 10mm. RESULTS The shoulders had significantly greater anterior translation when the posterior capsule was artificially tightened (p < 0.05); this was particularly in movements that combined abduction with internal or external rotation, which are typical overhead sports motions. Overall translation was indifferent to whether the shoulders were intact or dissected down to the capsule, as was translation during flexion was indifferent to dissection state (p > 0.95). CONCLUSION Surgical navigation technology can easily be used to analyze cadaveric shoulder motion, with opportunities for adaptation to anesthetized patients. Results suggest that the inverse of artificial tightening, such as surgical release of the posterior capsule, may be an effective minimally invasive treatment of chronic shoulder dislocation subsequent to sports motions.
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Affiliation(s)
- S Zakani
- Department of Mechanical and Materials Engineering, Queen's University, Kingston, ON, Canada.
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Howard JP, Jones DA, Gallagher S, Rathod K, Jain A, Mohiddin S, Knight C, Mathur A, Smith EJ, Wragg A. 048 Is it safe to discharge patients 24 h after uncomplicated successful primary percutaneous coronary intervention?: Abstract 048 Table 1. Heart 2012. [DOI: 10.1136/heartjnl-2012-301877b.48] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Bhardwaj G, Ko KD, Hong Y, Zhang Z, Ho NL, Chintapalli SV, Kline LA, Gotlin M, Hartranft DN, Patterson ME, Dave F, Smith EJ, Holmes EC, Patterson RL, van Rossum DB. PHYRN: a robust method for phylogenetic analysis of highly divergent sequences. PLoS One 2012; 7:e34261. [PMID: 22514627 PMCID: PMC3325999 DOI: 10.1371/journal.pone.0034261] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2011] [Accepted: 02/24/2012] [Indexed: 11/19/2022] Open
Abstract
Both multiple sequence alignment and phylogenetic analysis are problematic in the "twilight zone" of sequence similarity (≤ 25% amino acid identity). Herein we explore the accuracy of phylogenetic inference at extreme sequence divergence using a variety of simulated data sets. We evaluate four leading multiple sequence alignment (MSA) methods (MAFFT, T-COFFEE, CLUSTAL, and MUSCLE) and six commonly used programs of tree estimation (Distance-based: Neighbor-Joining; Character-based: PhyML, RAxML, GARLI, Maximum Parsimony, and Bayesian) against a novel MSA-independent method (PHYRN) described here. Strikingly, at "midnight zone" genetic distances (~7% pairwise identity and 4.0 gaps per position), PHYRN returns high-resolution phylogenies that outperform traditional approaches. We reason this is due to PHRYN's capability to amplify informative positions, even at the most extreme levels of sequence divergence. We also assess the applicability of the PHYRN algorithm for inferring deep evolutionary relationships in the divergent DANGER protein superfamily, for which PHYRN infers a more robust tree compared to MSA-based approaches. Taken together, these results demonstrate that PHYRN represents a powerful mechanism for mapping uncharted frontiers in highly divergent protein sequence data sets.
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Affiliation(s)
- Gaurav Bhardwaj
- Center for Computational Proteomics, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Department of Biochemistry and Molecular Medicine, School of Medicine, University of California Davis, Davis, California, United States of America
- Center for Translational Bioscience and Computing, University of California Davis, Davis, California, United States of America
| | - Kyung Dae Ko
- Center for Computational Proteomics, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Yoojin Hong
- Center for Computational Proteomics, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Department of Computer Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Zhenhai Zhang
- Center for Computational Proteomics, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Ngai Lam Ho
- Center for Computational Proteomics, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Department of Computer Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Sree V. Chintapalli
- Department of Physiology and Membrane Biology, School of Medicine, University of California Davis, Davis, California, United States of America
- Center for Translational Bioscience and Computing, University of California Davis, Davis, California, United States of America
| | - Lindsay A. Kline
- Center for Computational Proteomics, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Matthew Gotlin
- Center for Computational Proteomics, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - David Nicholas Hartranft
- Center for Computational Proteomics, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Morgen E. Patterson
- Center for Computational Proteomics, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Foram Dave
- Center for Computational Proteomics, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Evan J. Smith
- Center for Computational Proteomics, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Edward C. Holmes
- Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Fogarty International Center, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Randen L. Patterson
- Center for Computational Proteomics, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Department of Biochemistry and Molecular Medicine, School of Medicine, University of California Davis, Davis, California, United States of America
- Department of Physiology and Membrane Biology, School of Medicine, University of California Davis, Davis, California, United States of America
- Center for Translational Bioscience and Computing, University of California Davis, Davis, California, United States of America
| | - Damian B. van Rossum
- Center for Computational Proteomics, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Center for Translational Bioscience and Computing, University of California Davis, Davis, California, United States of America
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Zahos K, Mehendale S, Ward AJ, Smith EJ, Nichols M. The 15° face-changing acetabular component for treatment of osteoarthritis secondary to developmental dysplasia of the hip. J Bone Joint Surg Br 2012; 94:163-166. [PMID: 22323679 DOI: 10.1302/0301-620x.94b2.27348] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We report the use of a 15° face-changing cementless acetabular component in patients undergoing total hip replacement for osteoarthritis secondary to developmental dysplasia of the hip. The rationale behind its design and the surgical technique used for its implantation are described. It is distinctly different from a standard cementless hemispherical component as it is designed to position the bearing surface at the optimal angle of inclination, that is, < 45°, while maximising the cover of the component by host bone.
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Affiliation(s)
- K Zahos
- Southmead Hospital, Avon Orthopaedic Centre, North Bristol NHS Trust, Westbury-on-Trym, Bristol BS10 5NB, UK
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Smith EJ. Use of Sulphur-containing Compounds, particularly Pentothal Sodium, in Conjunction with Sulphapyridine. Br Med J 2011; 2:488-9. [PMID: 20783337 DOI: 10.1136/bmj.2.4162.488] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Abstract
In February 1992, the Ulysses spacecraft flew through the giant magnetosphere of Jupiter. The primary objective of the encounter was to use the gravity field of Jupiter to redirect the spacecraft to the sun's polar regions, which will now be traversed in 1994 and 1995. However, the Ulysses scientific investigations were well suited to observations of the Jovian magnetosphere, and the encounter has resulted in a major contribution to our understanding of this complex and dynamic plasma environment. Among the more exciting results are (i) possible entry into the polar cap, (ii) the identification of magnetospheric ions originating from Jupiter's ionosphere, lo, and the solar wind, (iii) observation of longitudinal asymmetries in density and discrete wave-emitting regions of the lo plasma torus, (iv) the presence of counter-streaming ions and electrons, field-aligned currents, and energetic electron and radio bursts in the dusk sector on high-latitude magnetic field lines, and (v) the identification of the direction of the magnetic field in the dusk sector, which is indicative of tailward convection. This overview serves as an introduction to the accompanying reports that present the preliminary scientific findings. Aspects of the encounter that are common to all of the investigations, such as spacecraft capabilities, the flight path past Jupiter, and unique aspects of the encounter, are presented herein.
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Smith EJ, Ray SA, Drummond PB. A MboI polymorphism in the turkey revealed by (TCC)5 single primer amplified DNA fragment. Anim Genet 2009. [DOI: 10.1111/j.1365-2052.1996.tb00962.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Bacon LD, Smith EJ, Fadly AM, Crittenden LB. Development of an alloantiserum (R2) that detects susceptibility of chickens to subgroup E endogenous avian leukosis virus. Avian Pathol 2009; 25:551-68. [PMID: 18645878 DOI: 10.1080/03079459608419161] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
An alloantiserum, termed R2, specifically agglutinates red blood cells (RBC) from line 100B chickens that are susceptible to avian leukosis viruses (ALV) belonging to subgroups B and E, but does not agglutinate RBC from congenic inbred line 7(2) chickens that are resistant to ALV B and E. The R2 antigen was also detected on lymphocytes and thrombocytes. Using chickens from a special cross, it was found that R2 reactivity requires that the chickens must: (1) be susceptible to infection by ALV-E; and (2) express a viral envelope gene with subgroup E specificity. With R2 antiserum, a nearly perfect association was observed between agglutination and susceptibility to ALV-B in F2 chickens containing endogenous viral genes ev2 and/or ev3. These results support earlier evidence that ALV-B and ALV-E share receptors. Moreover, the R2 antiserum was shown to neutralize ALV-E. The R2 antigen showed Mendelian segregation in chickens of a commercial White Leghorn strain-cross containing ev3, ev6 and ev9. However, commercial chickens with or without the R2 antigen did not differ in susceptibility to lymphoid leukosis induction or immune response on infection with ALV of subgroup A for complex reasons we discuss.
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Affiliation(s)
- L D Bacon
- US Department of Agriculture, Agricultural Research Service, Avian Disease and Oncology Laboratory, East Lansing, Michigan, USA
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35
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Fadly AM, Witter RL, Smith EJ, Silva RF, Reed WM, Hoerr FJ, Putnam MR. An outbreak of lymphomas in commercial broiler breeder chickens vaccinated with a fowlpox vaccine contaminated with reticuloendotheliosis virus. Avian Pathol 2009; 25:35-47. [PMID: 18645835 DOI: 10.1080/03079459608419118] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Gross and microscopic examinations of affected tissues from chickens of two commercial broiler breeder flocks aged 27 and 31 weeks revealed lesions of visceral lymphomas with bursal involvement in some chickens. Reticuloendotheliosis virus (REV), but not avian leukosis virus (ALV), was isolated from blood of affected chickens. Furthermore, DNA extracted from tumours tested positive for REV, but not for ALV or Marek's disease virus by polymerase chain reaction (PCR) test. Attempts to determine the source of REV infection included testing a commercial fowlpox (FP) vaccine used to immunize flocks at 7 days of age. Chicken-embryo fibroblasts inoculated with the FP vaccine tested positive for REV by PCR and immunofluorescent tests. REV was also isolated from plasma of pathogen-free chickens experimentally inoculated with FP vaccine at hatch; two of eight (25%) inoculated chickens developed lymphomas by 34 weeks of age. Antigenic characterization of REV isolated from commercial broiler breeder chickens and from FP vaccine, using monoclonal antibodies, revealed that both isolates belong to subtype 3 of REV. The data represent the first report of an outbreak of REV-induced lymphomas in commercial chickens. The data also indicate that the source of REV infection is an REV-contaminated commercial FP vaccine.
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Affiliation(s)
- A M Fadly
- USDA-Agricultural Research Service, Avian Disease and Oncology Laboratory, East Lansing, MI, USA
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36
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White SP, Bainbridge J, Smith EJ. Assessment of magnification of digital pelvic radiographs in total hip arthroplasty using templating software. Ann R Coll Surg Engl 2009; 90:592-6. [PMID: 18831869 DOI: 10.1308/003588408x318101] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
INTRODUCTION Templating of pelvic radiographs traditionally involved using implant-company provided acetates which assumed a magnification of 115-120%. With the introduction of digital imaging, many departments are becoming filmless. Templating software has been designed to allow on-screen templating of digital images. Knowledge of the true magnification of the image is required for accurate measurement. PATIENTS AND METHODS Fifty consecutive postoperative pelvic radiographs were analysed using templating software. The implanted component was measured using an assumed magnification factor of 115%. The template image was then reset to the known component size, and the magnification factor was adjusted until the template covered the true component. RESULTS An assumed magnification factor of 115% oversized the acetabular component by a mean of 6 mm (three component sizes) in all 50 components. The mean true magnification in our department was 127%. CONCLUSIONS Validation of the true magnification produced by a radiology department using templating software is a simple and reproducible technique. It is recommended to all departments using digital images and templating software. Assumption of a magnification factor of 115% risks oversizing components by 6 mm.
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Affiliation(s)
- S P White
- University Hospital of Wales, Cardiff, UK.
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Abstract
INTRODUCTION There is a strong drive from patients, industry and the media to perform total hip arthroplasty (THA) through a minimal access incision. Currently in the UK, the exact definition and uptake of this procedure is not known. PATIENTS AND METHODS A postal questionnaire was sent to all consultant orthopaedic surgeons in the UK registered with the British Orthopaedic Association. RESULTS Of those performing THA, 23% have performed minimal access hip surgery (MAS). Of users, 63% perform less than 20 cases per year, 62% use the mini-posterior approach, and 12% intend to perform MAS in the future. There is an association with specialisation. The mean and mode scar sizes for MAS were 9.9 cm and 10 cm, respectively. CONCLUSIONS MAS is increasing in popularity but is currently performed in small numbers by those with a specialist interest in hip arthroplasty. Because no long-term results have been published regarding this procedure, it will be important to ensure that standards of implantation are not jeopardised and training remains critical. Cases should be registered with the National Joint Registry using the current definition of scar size less than 10 cm.
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Affiliation(s)
- S P White
- Avon Orthopaedic Centre, Southmead Hospital, Bristol, UK.
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Kamara D, Gyenai KB, Geng T, Hammade H, Smith EJ. Microsatellite marker-based genetic analysis of relatedness between commercial and heritage turkeys (Meleagris gallopavo). Poult Sci 2007; 86:46-9. [PMID: 17179414 DOI: 10.1093/ps/86.1.46] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The turkey is second only to the chicken in importance as an agriculturally important poultry species. Unlike the chicken, however, genetic studies of the turkey continue to be limited. For example, to date, many genomic investigations have been conducted to characterize genetic relationships between commercial (CO) and non-CO chicken breeds, whereas the nature of the genetic relatedness between CO and heritage turkeys remains unknown. The objective of the current research was to use microsatellites to analyze the genetic relatedness between CO and heritage domestic turkeys including Narragansett, Bourbon Red, Blue Slate, Spanish Black, and Royal Palm. Primer pairs specific for 10 previously described turkey microsatellite markers were used. The phylogenetic analysis showed that the Blue Slate, Bourbon Red, and Narragansett were genetically closely related to the CO strain, with a Nei distance of 0.30, and the Royal Palm and Spanish Black were the least related to the CO strain, with Nei distances of 0.41 and 0.40, respectively. The present work provides a foundation for the basis of using heritage turkeys to genetically improve CO populations by introgression.
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Affiliation(s)
- D Kamara
- Department of Animal and Poultry Sciences, Virginia Tech, Blacksburg 24061, USA
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Lin KC, Gyenai K, Pyle RL, Geng T, Xu J, Smith EJ. Candidate gene expression analysis of toxin-induced dilated cardiomyopathy in the turkey (Meleagris gallopavo). Poult Sci 2007; 85:2216-21. [PMID: 17135679 DOI: 10.1093/ps/85.12.2216] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Dilated cardiomyopathy (DCM), a heart disease, affects many vertebrates including humans and poultry. The disease can be either idiopathic (IDCM) or toxin-induced (TIDCM). Although genetic and other studies of IDCM are extensive, the specific etiology of TIDCM is still unknown. In this study, we compared mRNA levels of cardiac troponin T (cTnT) and phospholamban (PLN) in turkeys affected and unaffected by TIDCM. Cardiac TnT and PLN were chosen because their altered expression has been observed in IDCM-affected birds. A total of 72 birds, 44 affected and 28 unaffected with TIDCM, were used. Differences in the mRNA levels of cTnT and PLN between affected and unaffected turkeys were significant only for cTnT. The sequence of the turkey PLN showed significant similarity at the nucleotide level to the reference chicken sequence and to those of other species. In addition to implicating cTnT in TIDCM, the present work describes a partial turkey PLN coding sequence that could be useful for future studies.
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Affiliation(s)
- K-C Lin
- Department of Animal and Poultry Sciences, Virginia Tech, Blacksburg 24061, USA
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40
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Breathnach AS, Riley PA, Shad S, Jownally SM, Law R, Chin PC, Kaufmann ME, Smith EJ. An outbreak of wound infection in cardiac surgery patients caused by Enterobacter cloacae arising from cardioplegia ice. J Hosp Infect 2006; 64:124-8. [PMID: 16899327 DOI: 10.1016/j.jhin.2006.06.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2006] [Accepted: 06/02/2006] [Indexed: 10/24/2022]
Abstract
This paper describes an outbreak of postoperative sternal wound infections. A cardiac surgeon noted a cluster of serious infections leading to wound dehiscence, despite the fact that none of his colleagues had noticed a rise in infection rates. The infections were predominantly with Enterobacter cloacae, and molecular typing and serotyping showed these isolates to be indistinguishable. Observation of the surgeon's practice revealed nothing untoward, and there were no infections among his patients operated on in another hospital. There appeared to be no significant difference between the modes of operation of the different surgeons. The operating theatres were screened to exclude an environmental source, with samples cultured on CHROMagar Orientation, a selective/differential medium designed for urine samples. Further questioning revealed one difference between the practices of the different surgeons; this surgeon used semi-frozen Hartmann's solution to achieve cardioplegia. The freezer used for this was swabbed and yielded E. cloacae, indistinguishable from the clinical isolates. It is hypothesized that this organism contaminated the freezer, and that the contamination was passed on to the ice/slush solution, thus infecting the patients. There have been no more cases since the freezer was replaced, a rigorous cleaning schedule instituted, and steps taken to reduce the possibility of any further contamination.
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Affiliation(s)
- A S Breathnach
- Department of Microbiology & Infection Control and Health Protection Agency Collaborating Centre, St George's Hospital, London, UK.
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Abstract
Expression studies suggest that the incidence and severity of tibial dyschondroplasia (TD) in chickens, Gallus gallus, may be affected by the aggrecan gene, AGC 1. Here, results are described of a scan for single nucleotide polymorphisms (SNP) in AGC1 in genetic lines divergently selected for TD incidence in chickens. A total of 3,048 bp of DNA sequence obtained from amplicons produced by 4 primer-pairs designed from the GenBank AGC1 cDNA sequence were scanned for SNP. Among the 18 SNP detected and validated, only 2 were nonsynonymous. Allelic frequency differences between TD-affected and nonaffected birds were not statistically significant for all the SNP. The current results do not support an association of Gallus gallus AGC1 variation at the DNA level with the incidence of TD in chickens. The genomic resources described, however, including the SNP, could be useful in further evaluating AGC1 in other populations for association with TD or other skeletal abnormalities.
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Affiliation(s)
- S A Ray
- Comparative Genomics Laboratory, Department of Animal and Poultry Sciences, Virginia Tech, Blacksburg 24061, USA
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Abstract
In total hip arthroplasty 32 mm heads are often used as the greater diameter is thought to contribute to improved stability. However, greater head diameter can also lead to greater volumetric wear. We compared polyethylene wear between patients with 32 mm heads and those with smaller heads. All patients who had Harris Galante1 metal-backed, uncemented cups inserted between 1986 and 1996 at our institute were annually reviewed clinically and radiographically. Accelerated polyethylene wear was noted between the fifth and seventh postoperative year in 17 out of 165 total hip replacements with 32 mm heads, but only in 21 out of 961 total hip arthroplasties with smaller femoral heads. In all 17 THRs, accelerated wear was also associated with thin polyethylene (<6 mm). This paper highlights a potentially serious problem. When 32 mm metal heads are used with uncemented cups and polyethylene liners, there is a risk of accelerated acetabular wear in patients with thin polyethylene.
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Affiliation(s)
- A W Blom
- Consultant Orthopaedic Surgeon, Southmead Hospital, Bristol, UK.
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Giampieri G, Dougherty MK, Smith EJ, Russell CT. A regular period for Saturn's magnetic field that may track its internal rotation. Nature 2006; 441:62-4. [PMID: 16672964 DOI: 10.1038/nature04750] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2006] [Accepted: 03/20/2006] [Indexed: 11/09/2022]
Abstract
The rotation rate of a planet is one of its fundamental properties. Saturn's rotation, however, is difficult to determine because there is no solid surface from which to time it, and the alternative 'clock'--the magnetic field--is nearly symmetrically aligned with the rotation axis. Radio emissions, thought to provide a proxy measure of the rotation of the magnetic field, have yielded estimates of the rotation period between 10 h 39 min 22 s and 10 h 45 min 45 s (refs 8-10). Because the period determined from radio measurements exhibits large time variations, even on timescales of months, it has been uncertain whether the radio-emission periodicity coincides with the inner rotation rate of the planet. Here we report magnetic field measurements that revealed a time-stationary magnetic signal with a period of 10 h 47 min 6 s +/- 40 s. The signal appears to be stable in period, amplitude and phase over 14 months of observations, pointing to a close connection with the conductive region inside the planet, although its interpretation as the 'true' inner rotation period is still uncertain.
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Affiliation(s)
- G Giampieri
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109, USA.
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44
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Affiliation(s)
- E J Smith
- London Chest Hospital, Bonner Road, London E2 9JX, UK
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45
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White SP, Blom AW, Lee M, Smith EJ. The crescent sign: dissociation of the polyethylene liner from a modular acetabular component in total hip arthroplasty. Skeletal Radiol 2005; 34:620-4. [PMID: 15981009 DOI: 10.1007/s00256-005-0927-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2005] [Accepted: 03/31/2005] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To study whether there was a common pattern of clinical symptoms, signs and radiographic features for the dissociation of the polyethylene liner from an acetabular component and to postulate reasons for these features. DESIGN AND PATIENTS Retrospective study of notes and radiographs of cases of revision hip arthroplasty for polyethylene liner dissociation of the cementless Harris-Galante I porous-coated acetabular component (Zimmer Inc, Warsaw, IN) at the Avon Orthopaedic Centre, Bristol, UK and St. Mary's Hospital, Bristol, UK between 1995 and 2004. Patients were contacted to confirm preoperative symptoms. RESULTS Nine cases of late polyethylene liner dissociation of this prosthesis have been revised in these institutions. All patients presented with a reduction in mobility, groin pain and limp. Eight patients reported an audible noise on hip movement. In all cases, radiographs showed radiolucency medial to the femoral neck in association with an eccentrically placed femoral head showing contact with the acetabular metal shell, which we have termed the "crescent sign." CONCLUSIONS There is a typical clinical presentation in this study. The diagnosis can be made from a single anteroposterior pelvic radiograph without the need for previous films for comparison, or the need for arthrography. Clinicians should look specifically for the crescent sign when an eccentrically placed femoral head has been noted, in order to differentiate the more unusual diagnosis of dissociation from that of polyethylene wear. Early revision surgery can prevent damage to the femoral head and metal acetabular shell, thus reducing the complexity of revision surgery.
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Affiliation(s)
- S P White
- Avon Orthopaedic Centre, Bristol, United Kingdom.
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Smith EJ, Bryk T, Haymet ADJ. Free energy of solvation of simple ions: Molecular-dynamics study of solvation of Cl− and Na+ in the ice/water interface. J Chem Phys 2005; 123:34706. [PMID: 16080754 DOI: 10.1063/1.1953578] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Molecular-dynamics simulations of Cl(-) and Na(+) ions are performed to calculate ionic solvation free energies in both bulk simple point-charge/extended water and ice 1 h at several different temperatures, and at the basal ice 1 h/water interface. For the interface we calculate the free energy of "transfer" of the ions across the ice/water interface. For the ions in bulk water in the NPT ensemble at 298 K and 1 atm, results are found to be in good agreement with experiments, and with other simulation results. Simulations performed in the NVT ensemble are shown to give equivalent solvation free energies, and this ensemble is used for the interfacial simulations. Solvation free energies of Cl(-) and Na(+) ions in ice at 150 K are found to be approximately 30 and approximately 20 kcal mol(-1), respectively, less favorable than for water at room temperature. Near the melting point of the model the solvation of the ions in water is the same (within statistical error) as that measured at room temperature, and in the ice is equivalent and approximately 10 kcal mol(-1) less favorable than the liquid. The free energy of transfer for each ion across ice/water interface is calculated and is in good agreement with the bulk observations for the Cl(-) ion. However, for the model of Na(+) the long-range electrostatic contribution to the free energy was more negative in the ice than the liquid, in contrast with the results observed in the bulk calculations.
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Affiliation(s)
- E J Smith
- Department of Chemistry, University of Houston, Texas 77204-5003, USA
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Smith EJ, Hughes S, Lawlor AJ, Lofts S, Simon BM, Stevens PA, Stidson RT, Tipping E, Vincent CD. Potentially toxic metals in ombrotrophic peat along a 400 km English-Scottish transect. Environ Pollut 2005; 136:11-18. [PMID: 15809104 DOI: 10.1016/j.envpol.2004.12.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2004] [Accepted: 12/14/2004] [Indexed: 05/24/2023]
Abstract
Four samples of ombrotrophic peat were collected from each of 10 upland locations in a transect from the southern Pennines to the Highland Boundary Fault, a total distance of ca. 400 km. Bulk compositions and other properties were determined. Total contents of Al and heavy metals (Ni, Cu, Zn, Cd, Pb) were determined following digestion with hydrofluoric acid, and concentrations of metals extractable with dilute nitric acid were also measured. Supernatants obtained from aqueous extractions of the peat samples were analysed for pH, major cations and anions, dissolved organic carbon and dissolved metals, and concentrations of free metal ions (Al(3+), Ni(2+), etc.) were estimated by applying a chemical speciation model. Both total and HNO(3)-extractable metal concentrations varied along the transect, the highest values being found at locations close to industrial and former mining areas. The HNO(3)-extractable soil metal contents of Ni, Cu and Cd were appreciably lower than lowest-observed-effect-concentrations (LOEC) for toxicity towards microorganisms in acid, organic rich soils. However, the contents of Zn at two locations, and of Pb at five locations exceeded LOECs, suggesting that they may be exerting toxic effects in the peats. Soil solution concentrations of free heavy metal ions (Cu(2+), Zn(2+), Cd(2+), Pb(2+)) were substantially lower than LOECs for toxicity towards vascular plants, whereas concentrations of Al(3+) were near to toxic levels at two locations.
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Affiliation(s)
- E J Smith
- Centre for Ecology and Hydrology (Lancaster), Lancaster Environment Centre, Bailrigg, Lancaster LA1 4AP, UK
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48
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Dougherty MK, Achilleos N, Andre N, Arridge CS, Balogh A, Bertucci C, Burton ME, Cowley SWH, Erdos G, Giampieri G, Glassmeier KH, Khurana KK, Leisner J, Neubauer FM, Russell CT, Smith EJ, Southwood DJ, Tsurutani BT. Cassini Magnetometer Observations During Saturn Orbit Insertion. Science 2005; 307:1266-70. [PMID: 15731444 DOI: 10.1126/science.1106098] [Citation(s) in RCA: 195] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Cassini's successful orbit insertion has provided the first examination of Saturn's magnetosphere in 23 years, revealing a dynamic plasma and magnetic environment on short and long time scales. There has been no noticeable change in the internal magnetic field, either in its strength or its near-alignment with the rotation axis. However, the external magnetic field is different compared with past spacecraft observations. The current sheet within the magnetosphere is thinner and more extended, and we observed small diamagnetic cavities and ion cyclotron waves of types that were not reported before.
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Affiliation(s)
- M K Dougherty
- Blackett Laboratory, Imperial College London, SW7 2AZ, UK.
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Smith EJ, Hussain A, Manoharan M, Testa HJ, Curzen NP. A reverse perfusion pattern during Technetium-99m stress myocardial perfusion imaging does not predict flow limiting coronary artery disease. Int J Cardiovasc Imaging 2004; 20:321-6. [PMID: 15529916 DOI: 10.1023/b:caim.0000041951.48335.1a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
BACKGROUND A reverse redistribution pattern during myocardial perfusion imaging is most widely described using thallium (Tl-201), when stress images exhibit greater perfusion than rest. Technetium (Tc-99 m) radiopharmaceuticals may also yield a reverse perfusion (RP) pattern, but its significance is uncertain. This study tested the hypothesis that RP correlates with the presence and location of flow limiting coronary stenosis(es). METHOD We reviewed 842 consecutive Tc-99 m tetrofosmin SPECT stress studies performed at a cardiothoracic centre over a 15 month period. 69 (8.2%) demonstrated RP. Thirty-three patients (age 32-79 mean 56, 17 female) had undergone cardiac catheterisation within 12 months of the scan. Correlation was sought between the presence and location of angiographic stenoses and RP pattern. RESULTS 10/33 (30.3%) had significant (>60%) coronary stenosis(es); 5 single-vessel, 2 two-vessel and 3 three-vessel disease (3VD). Stenosis location correlated poorly with the RP territory (LAD/Anterior 5/17, RCA/Inferior 1/10, Cx/lateral 0/4 (p = 0.57)). Of the 6 patients with a lesion in the RP territory, 3 had 3VD; 2 of these had a simultaneous reversible defect. All 5 patients with previous myocardial infarction had a simultaneous fixed defect. However only 3/12 with co-existent reversible defects had significant disease. CONCLUSION The reverse perfusion pattern is a poor predictor of flow limiting coronary disease, and does not correlate with stenosis location in those with significant lesions. Such patients should not undergo invasive investigation purely on the basis of this result.
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Affiliation(s)
- E J Smith
- Department of Cardiology, Manchester Royal Infirmary, Manchester M13 9WL, England
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Ackroyd CE, Smith EJ, Newman JH. Trochlear resurfacing for extensor mechanism instability following patellectomy. Knee 2004; 11:109-11. [PMID: 15066620 DOI: 10.1016/s0968-0160(03)00079-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2002] [Revised: 05/12/2003] [Accepted: 06/02/2003] [Indexed: 02/02/2023]
Abstract
Patellectomy may in some cases result in persistent pain, weakness and instability of the knee. We report on three patients who had extensor tendon instability and were treated by trochlear resurfacing and extensor tendon realignment. All three cases achieved pain relief and an impressive improvement in knee function.
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Affiliation(s)
- C E Ackroyd
- Bristol Knee Group, Winford Unit, Avon Orthopaedic Centre, Westbury on Trym, Bristol BS10 5NB, UK.
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