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Nyring MRK, Rasmussen JV, Gill DRJ, Harries D, Olsen BS, Page RS. Comparable low revision rates of stemmed and stemless total anatomic shoulder arthroplasties after exclusion of metal backed glenoid components: a collaboration between the Australian and Danish national shoulder arthroplasty registries. J Shoulder Elbow Surg 2024:S1058-2746(24)00303-3. [PMID: 38685378 DOI: 10.1016/j.jse.2024.03.022] [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] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 02/16/2024] [Accepted: 03/03/2024] [Indexed: 05/02/2024]
Abstract
BACKGROUND The stemmed anatomical total shoulder arthroplasty is the gold standard in the treatment of glenohumeral osteoarthritis. However, the use of stemless total shoulder arthroplasties has increased in recent years. The number of revision procedures are relatively low and therefore it has been recommended that national joint replacement registries should collaborate when comparing revision rates. Therefore, we aimed to compare the revision rates of stemmed and stemless TSA used for the diagnosis of glenohumeral osteoarthritis using data from both the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) and the Danish Shoulder Arthroplasty Registry (DSR). METHODS We included all patients who were registered in the AOANJRR and the DSR from January 1 2012 to December 2021 with an anatomical total shoulder arthroplasty used for osteoarthritis. Revision for any reason was used as the primary outcome. We used the Kaplan-Meier method to illustrate the cumulative revision rates and a multivariate cox regression model to calculate the hazard ratios. All analyses were performed separately for data from AOANJRR and DSR, and the results were then reported using a qualitative approach. RESULTS 13066 arthroplasties from AOANJRR and 2882 arthroplasties from DSR were included. The hazard ratio for revision of stemmed TSA with stemless TSA as reference, adjusted for age and gender, was 1.67 (95% CI 1.34-2.09, p<0.001) in AOANJRR and 0.57 (95% CI 0.36-0.89, p=0.014) in DSR. When including glenoid type and fixation, surface bearing (only in AOANJRR) and hospital volume in the cox regression model the hazard ratio for revision of stemmed TSA compared to stemless TSA was 1.22 (95% CI 0.85-1.75, p=0.286) in AOANJRR and 1.50 (95% CI 0.91-2.45, p=0.109) in DSR. The adjusted hazard ratio for revision of total shoulder arthroplasties with metal backed glenoid components compared to all-polyethylene glenoid components was 2.54 (95% CI 1.70-3.79, p < 0.001) in AOANJRR and 4.1 (95% CI 1.92-8.58, p<0.001) in DSR. CONCLUSION Based on data from two national shoulder arthroplasty registries, we found no significant difference in risk of revision between stemmed and stemless total shoulder arthroplasties after adjusting for the type of glenoid component. We advocate that metal-backed glenoid components should be used with caution and not on a routine basis.
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Affiliation(s)
- Marc R K Nyring
- Department of Orthopedic Surgery, Herlev and Gentofte Hospital, Hellerup, Denmark.
| | - Jeppe V Rasmussen
- Department of Orthopedic Surgery, Herlev and Gentofte Hospital, Hellerup, Denmark
| | - David R J Gill
- Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR), Adelaide, SA, Australia
| | - Dylan Harries
- South Australia Health and Medical Research Institute (SAHMRI), Adelaide, SA, Australia; Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR), Adelaide, SA, Australia
| | - Bo S Olsen
- Department of Orthopedic Surgery, Herlev and Gentofte Hospital, Hellerup, Denmark
| | - Richard S Page
- Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR), Adelaide, SA, Australia; Barwon Centre for Orthopaedic Research and Education (B-CORE), St John of God Hospital and Deakin University, Geelong, VIC, Australia
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Zhou Y, Harries D, Stoney JD. A Polished Cobalt-Chrome Baseplate is not Associated With a Lower Revision Rate Than Matt Titanium in a Single Total Knee Arthroplasty Implant System With Identical Baseplate Design. J Arthroplasty 2024; 39:896-903. [PMID: 37852451 DOI: 10.1016/j.arth.2023.10.003] [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] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 09/29/2023] [Accepted: 10/02/2023] [Indexed: 10/20/2023] Open
Abstract
BACKGROUND Polished baseplates were introduced into total knee arthroplasty (TKA) systems to reduce the incidence of backside wear. In 2004, a fixed-bearing knee arthroplasty system underwent a change in baseplate material from matt titanium to polished cobalt-chrome (CoCr) with the intention to reduce backside wear. Other design aspects were left unchanged. The aim of this study was to compare these implants with each baseplate using data from the Australian Orthopaedic Association National Joint Replacement Registry. METHODS Primary TKA procedures performed between January 2010 and December 2021 for osteoarthritis, using a single design with cross-linked polyethylene inserts and matt titanium or polished CoCr baseplates, were analyzed. The primary outcome was all-cause revision, summarized using Kaplan-Meier estimates, with age- and sex-adjusted hazard ratios estimated from Cox proportional hazards models. In total, there were 2,091 procedures with matt titanium and 2,519 procedures with polished CoCr baseplates. RESULTS The 9-year cumulative percent revision was 2.5% (95% confidence interval [CI] 1.8 to 3.5%) and 4.2% (95% CI 3.1 to 5.6%) for the matt titanium and CoCr groups, respectively. Compared to matt titanium, the revision rate of CoCr baseplates was not significantly higher (hazard ratio 1.44; 95% CI 0.96 to 2.15; P = .076). CONCLUSIONS Polished CoCr baseplates in a single TKA system were not associated with reduced all-cause revision rates compared to matt titanium up to 11 years post-TKA. Our results suggest that the predicted reduction in wear particle debris production from polished CoCr baseplates may not correlate with reduced revision rates in vivo, but further evaluation is required.
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Affiliation(s)
- Yushy Zhou
- Department of Orthopaedic Surgery, St. Vincent's Hospital, The University of Melbourne, Victoria, South Australia
| | - Dylan Harries
- South Australian Health and Medical Research Institute (SAHMRI), Adelaide, South Australia
| | - James D Stoney
- Department of Orthopaedic Surgery, St. Vincent's Hospital, The University of Melbourne, Victoria, South Australia; Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR), Adelaide, South Australia
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Lewin AM, Cashman K, Harries D, Ackerman IN, Naylor JM, Harris IA. First knee for pain and function versus second knee for quality of life. Bone Jt Open 2024; 5:202-209. [PMID: 38461859 PMCID: PMC10924693 DOI: 10.1302/2633-1462.53.bjo-2023-0035.r1] [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] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/12/2024] Open
Abstract
Aims The aim of this study was to describe and compare joint-specific and generic health-related quality of life outcomes of the first versus second knee in patients undergoing staged bilateral total knee arthroplasty (BTKA) for osteoarthritis. Methods This retrospective cohort study used Australian national arthroplasty registry data from January 2013 to January 2021 to identify participants who underwent elective staged BTKA with six to 24 months between procedures. The primary outcome was Oxford Knee Score (OKS) at six months postoperatively for the first TKA compared to the second TKA, adjusted for age and sex. Secondary outcomes compared six-month EuroQol five-dimension five-level (EQ-5D-5L) domain scores, EQ-5D index scores, and the EQ visual analogue scale (EQ-VAS) between knees at six months postoperatively. Results The cohort included 635 participants (1,270 primary procedures). Preoperative scores were worse in the first knee compared to the second for all instruments; however, comparing the first knee at six months postoperatively with the second knee at six months postoperatively, the mean between-knee difference was minimal for OKS (-0.8 points; 95% confidence interval (CI) -1.4 to -0.2), EQ-VAS (3.3; 95% CI 1.9 to 4.7), and EQ-5D index (0.09 points; 95% CI 0.07 to 0.12). Outcomes for the EQ-5D-5L domains 'mobility', 'usual activities', and 'pain/discomfort' were better following the second TKA. Conclusion At six months postoperatively, there were no clinically meaningful differences between the first and second TKA in either the joint-specific or overall generic health-related quality of life outcomes. However, individual domain scores assessing mobility, pain, and usual activities were notably higher after the second TKA, likely reflecting the cumulative improvement in quality of life after both knees have been replaced.
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Affiliation(s)
- Adriane M. Lewin
- South West Clinical Campuses, School of Clinical Medicine, UNSW Medicine & Health, Liverpool, Australia
- Whitlam Orthopaedic Research Centre, Ingham Institute for Applied Medical Research, Liverpool, Australia
| | - Kara Cashman
- South Australian Health and Medical Research Institute, Adelaide, Australia
| | - Dylan Harries
- South Australian Health and Medical Research Institute, Adelaide, Australia
| | - Ilana N. Ackerman
- School of Public Health and Preventive Medicine, Monash University, Melbourne, Australia
| | - Justine M. Naylor
- South West Clinical Campuses, School of Clinical Medicine, UNSW Medicine & Health, Liverpool, Australia
- Whitlam Orthopaedic Research Centre, Ingham Institute for Applied Medical Research, Liverpool, Australia
- South West Sydney Local Health District, NSW Health, Sydney, Australia
| | - Ian A. Harris
- South West Clinical Campuses, School of Clinical Medicine, UNSW Medicine & Health, Liverpool, Australia
- Whitlam Orthopaedic Research Centre, Ingham Institute for Applied Medical Research, Liverpool, Australia
- South West Sydney Local Health District, NSW Health, Sydney, Australia
- Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR), Adelaide, Australia
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Osan JK, Harris IA, Harries D, Peng Y, Yates PJ, Jones CW. Stemmed Tibial Fixation for Primary Total Knee Arthroplasty in Obese Patients-A National Registry Study. J Arthroplasty 2024; 39:355-362. [PMID: 37586598 DOI: 10.1016/j.arth.2023.08.028] [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] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Revised: 08/06/2023] [Accepted: 08/08/2023] [Indexed: 08/18/2023] Open
Abstract
BACKGROUND We investigated if the use of augmented tibial fixation with stems in primary total knee arthroplasty (TKA) in obese patients was associated with a difference in reason for revision, type of revision, or overall revision rate. METHODS Data from the Australian Orthopaedic Association National Joint Replacement Registry compared reason for revision, rate, and type of revision between primary TKA using stemmed tibial prostheses to nonstemmed prostheses, stratified by body mass index (BMI) and obesity. The cumulative percent revision was obtained using the Kaplan-Meier method, and Cox proportional hazards models estimated hazard ratios (HRs) adjusted for age and sex with 95% confidence intervals (CIs). All tests were 2-tailed at 5% statistical significance (P < .05). There were 66,508 procedures available for analyses. RESULTS Obese class 2 (BMI 35 to 39.99) had higher rates of revision in the stemmed group compared to the nonstemmed group (HR 1.44, 95% CI 1.00, 2.05, P = .047). There was no significant difference in revision rates between stemmed and nonstemmed tibial prostheses in any other BMI group. Primary TKA in obese patients (BMI ≥30) with a stem extension had a significantly higher rate of minor revisions compared to no stem extension (HR 1.31, 95% CI 1.03, 1.66, P = .025). There was no significant difference between stemmed and nonstemmed groups for major revision in obese patients and for minor or major revision in nonobese patients. CONCLUSION Using a tibial stem during primary TKA in obese patients is not associated with a lower rate of revision.
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Affiliation(s)
- Jessica K Osan
- Orthopaedic Research Foundation of Western Australia, Perth, Western Australia; Department of Orthopaedics, Fiona Stanley Hospital, Perth, Western Australia
| | - Ian A Harris
- Ingham Institute for Applied Medical Research, South Western Sydney Clinical School, UNSW Sydney, Liverpool Hospital, Liverpool, New South Wales, Australia
| | - Dylan Harries
- Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR), Adelaide, South Australia; South Australian Health and Medical Research Institute (SAHMRI), Adelaide, South Australia
| | - Yi Peng
- Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR), Adelaide, South Australia; South Australian Health and Medical Research Institute (SAHMRI), Adelaide, South Australia
| | - Piers J Yates
- Department of Orthopaedics, Fiona Stanley Hospital, Perth, Western Australia; University of Western Australia, Perth, Western Australia; St John of God Murdoch, Perth, Western Ausltralia; Orthopaedics WA, St John of God Murdoch Private Hospital, Mount Hospital, Perth, Western Australia; Foundation of Western Australia, Perth, Western Australia
| | - Christopher W Jones
- Department of Orthopaedics, Fiona Stanley Hospital, Perth, Western Australia; Orthopaedics WA, St John of God Murdoch Private Hospital, Mount Hospital, Perth, Western Australia; Foundation of Western Australia, Perth, Western Australia; Curtin University, Perth, Western Australia; Mount Hospital, Perth, Western Australia
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Gill DRJ, Corfield S, Harries D, Page RS. A comparison of revision rates for stemmed and stemless primary anatomic shoulder arthroplasty with all-polyethylene glenoid components: analysis from the Australian Orthopaedic Association National Joint Replacement Registry. J Shoulder Elbow Surg 2024; 33:281-290. [PMID: 37499786 DOI: 10.1016/j.jse.2023.06.025] [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] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 06/17/2023] [Accepted: 06/21/2023] [Indexed: 07/29/2023]
Abstract
BACKGROUND We compared the rate of all-cause revision of 2 classes of primary anatomic shoulder arthroplasty, stemmed (stTSA) and stemless (slTSA), undertaken with cemented all-polyethylene glenoid components. METHODS A large national arthroplasty registry identified 2 cohort groups for comparison, stTSA and l undertaken for all diagnoses between January 1, 2011, and December 31, 2021. A subanalysis from January 1, 2017, allowed capturing of additional patient demographics including American Society of Anesthesiologists score, body mass index, and glenoid morphology. The cumulative percent revision (CPR) was determined using Kaplan-Meier estimates of survivorship and hazard ratios (HR) from Cox proportional hazard models adjusted for age and gender. RESULTS Of the 7995 stTSA procedures, the CPR at 9 years was 5.6% (95% confidence interval [CI]: 5.0, 6.4), and for 3156 slTSA procedures, the CPR was 4.4% (95% CI: 3.6, 5.5). There was no significant difference in the rate of revision between the study groups (HR = 0.76 [95% CI: 0.51, 1.14], P = .189, adjusted for age, gender, humeral head size, humeral fixation, bearing surface, glenoid design, and mean surgeon volume [MSV]). There was an increased rate of revision for stTSA and slTSA undertaken with humeral head sizes <44 mm (stTSA <44 mm vs. 44-50 mm, HR = 1.56 [CI: 1.18, 2.08], P = .001; slTSA <44 mm vs. 44-50 mm, HR = 2.08 [CI: 1.32, 3.33], P = .001). MSV as a continuous predictor was not a revision risk to stTSA vs. slTSA, but categorically, a low MSV (<10 stTSA + slTSA cases per annum) was associated with a higher revision rate for stTSA (10-20 cases/yr vs. <10 cases/yr, HR = 0.72 [CI: 0.55, 0.95], P = .019) but was not in slTSA. Revision rates were increased for stTSA with non-crosslinked polyethylene (XLPE) glenoids vs. XPLE after 2 years (HR = 2.20 [CI: 1.57, 3.08], P < .001) but did not significantly differ for slTSA. Metal/XPLE (humeral/glenoid) bearing surface of stTSA rate of revision was not different from each combination of slTSA bearing surface. Instability/dislocation was a revision risk for slTSA vs. stTSA (HR = 1.93 [CI: 1.28, 2.91], P = .001), but from 2017, neither of American Society of Anesthesiologists score, body mass index, and glenoid morphology changed the rate of revision. CONCLUSIONS Revision rates of stTSA and slTSA did not significantly differ and were associated with humeral head size but not patient characteristics. Surgeon inexperience of anatomic shoulder arthroplasty and non-XLPE glenoids were risk factors for stTSA revision but not slTSA. The metal/XLPE stTSA rate of revision was not found to differ significantly from slTSA regardless of polyethylene or humeral head bearing type. Revision for instability/dislocation was more common for slTSA.
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Affiliation(s)
- David R J Gill
- Orthopaedics Central, Nedlands, WA, Australia; Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR), Adelaide, SA, Australia.
| | - Sophia Corfield
- Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR), Adelaide, SA, Australia
| | - Dylan Harries
- South Australia Health and Medical Research Institute (SAHMRI), Adelaide, SA, Australia
| | - Richard S Page
- Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR), Adelaide, SA, Australia; Barwon Centre for Orthopaedic Research and Education (B-CORE), St John of God Hospital and Deakin University, Geelong, VIC, Australia
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Osan JK, Harris IA, Harries D, Peng Y, Yates PJ, Jones CW. Utilizing Stems in Primary Total Knee Arthroplasty: Analysis of the Australian Orthopaedic Association National Joint Replacement Registry Data. J Arthroplasty 2024:S0883-5403(24)00031-7. [PMID: 38244637 DOI: 10.1016/j.arth.2024.01.031] [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] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2023] [Revised: 01/06/2024] [Accepted: 01/11/2024] [Indexed: 01/22/2024] Open
Abstract
BACKGROUND We compared revision rates and reasons for revision for primary total knee arthroplasty (TKA) performed for osteoarthritis with and without tibial stem extensions. METHODS Data from the Australian Orthopaedic Association National Joint Replacement Registry were used to compare all-cause revision, reason, and type of revision between primary TKA using stemmed tibial prostheses and non-stemmed prostheses. RESULTS All-cause revision for TKA with stem extension was higher for the first 6 months (hazard ratio [HR] 1.47; 95% confidence interval [CI]1.19 to 1.82; P < .001); while after 1.5 years TKA with stem extension had a lower rate of revision (HR 0.84; 95% CI 0.73 to 0.97; P = .01). Stemmed components were more likely to be revised for infection between 3 months and 1.5 years after surgery (HR 1.39; 95% CI 1.05 to 1.83; P = .02). The revision rate for aseptic loosening was lower in the stemmed group beyond 2 years (HR = 0.45; 95% CI 0.31 to 0.63; P < .001). Insert-only revision was higher in the stemmed group at all times (HR = 1.42; 95% CI 1.21 to 1.66, P < .001). Isolated tibial component revision was lower in the stemmed group at all times (HR 0.47; 95% CI 0.29 to 0.74; P = .001). Aseptic loosening for tibial component-only revision was significantly lower in the stemmed group at all times (HR 0.23; 95% CI 0.11 to 0.50; P < .001). CONCLUSIONS Patients undergoing primary stemmed TKA have lower rates of all-cause revision beyond 1.5 years and tibial component-only revision at all times. Further investigation is required to preoperatively select patients that benefit from augmentation with stems.
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Affiliation(s)
- Jessica K Osan
- Orthopaedic Research Foundation of Western Australia, Fiona Stanley Hospital Group, Perth, Western Australia, Australia
| | - Ian A Harris
- Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR), Adelaide, Australia; Ingham Institute for Applied Medical Research, South Western Sydney Clinical School, UNSW Sydney, Liverpool Hospital, Liverpool, New South Wales, Australia
| | - Dylan Harries
- Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR), Adelaide, Australia; South Australian Health and Medical Research Institute (SAHMRI), Adelaide, South Australia, Australia
| | - Yi Peng
- Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR), Adelaide, Australia; South Australian Health and Medical Research Institute (SAHMRI), Adelaide, South Australia, Australia
| | - Piers J Yates
- Orthopaedic Surgery University of Western Australia, St John of God Murdoch, Fiona Stanley Hospital Group, Orthopaedics WA, St John of God Murdoch Private Hospital, Mount Hospital, Orthopaedic Research Foundation of Western Australia, Perth, Australia
| | - Christopher W Jones
- Curtin University, Mount Hospital, Fiona Stanley Hospital Group Orthopaedics WA, St John of God Murdoch Private Hospital, Mount Hospital, Orthopaedic Research Foundation of Western Australia, Perth, Australia
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Leta TH, Fenstad AM, Lygre SHL, Lie SA, Lindberg-Larsen M, Pedersen AB, W-Dahl A, Rolfson O, Bülow E, Ashforth JA, Van Steenbergen LN, Nelissen RGHH, Harries D, De Steiger R, Lutro O, Hakulinen E, Mäkelä K, Willis J, Wyatt M, Frampton C, Grimberg A, Steinbrück A, Wu Y, Armaroli C, Molinari M, Picus R, Mullen K, Illgen R, Stoica IC, Vorovenci AE, Dragomirescu D, Dale H, Brand C, Christen B, Shapiro J, Wilkinson JM, Armstrong R, Wooster K, Hallan G, Gjertsen JE, Chang RN, Prentice HA, Paxton EW, Furnes O. The use of antibiotic-loaded bone cement and systemic antibiotic prophylactic use in 2,971,357 primary total knee arthroplasties from 2010 to 2020: an international register-based observational study among countries in Africa, Europe, North America, and Oceania. Acta Orthop 2023; 94:416-425. [PMID: 37565339 PMCID: PMC10416222 DOI: 10.2340/17453674.2023.17737] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [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: 03/27/2023] [Accepted: 06/02/2023] [Indexed: 08/12/2023] Open
Abstract
BACKGROUND AND PURPOSE Antibiotic-loaded bone cement (ALBC) and systemic antibiotic prophylaxis (SAP) have been used to reduce periprosthetic joint infection (PJI) rates. We investigated the use of ALBC and SAP in primary total knee arthroplasty (TKA). PATIENTS AND METHODS This observational study is based on 2,971,357 primary TKAs reported in 2010-2020 to national/regional joint arthroplasty registries in Australia, Denmark, Finland, Germany, Italy, the Netherlands, New Zealand, Norway, Romania, South Africa, Sweden, Switzerland, the UK, and the USA. Aggregate-level data on trends and types of bone cement, antibiotic agents, and doses and duration of SAP used was extracted from participating registries. RESULTS ALBC was used in 77% of the TKAs with variation ranging from 100% in Norway to 31% in the USA. Palacos R+G was the most common (62%) ALBC type used. The primary antibiotic used in ALBC was gentamicin (94%). Use of ALBC in combination with SAP was common practice (77%). Cefazolin was the most common (32%) SAP agent. The doses and duration of SAP used varied from one single preoperative dosage as standard practice in Bolzano, Italy (98%) to 1-day 4 doses in Norway (83% of the 40,709 TKAs reported to the Norwegian arthroplasty register). CONCLUSION The proportion of ALBC usage in primary TKA varies internationally, with gentamicin being the most common antibiotic. ALBC in combination with SAP was common practice, with cefazolin the most common SAP agent. The type of ALBC and type, dose, and duration of SAP varied among participating countries.
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Affiliation(s)
- Tesfaye H Leta
- The Norwegian Arthroplasty Register, Department of Orthopedic Surgery, Haukeland University Hospital, Norway; Faculty of Health Science, VID Specialized University, Norway; Department of Population Health Sciences, Weill Medical College of Cornell University, USA; Department of Medical Device Surveillance & Assessment, Kaiser Permanente, USA.
| | - Anne Marie Fenstad
- The Norwegian Arthroplasty Register, Department of Orthopedic Surgery, Haukeland University Hospital, Norway
| | - Stein Håkon L Lygre
- The Norwegian Arthroplasty Register, Department of Orthopedic Surgery, Haukeland University Hospital, Norway; Department of Occupational Medicine, Haukeland University Hospital, Norway
| | - Stein Atle Lie
- The Norwegian Arthroplasty Register, Department of Orthopedic Surgery, Haukeland University Hospital, Norway; Institutes of Dentistry, University of Bergen, Norway
| | - Martin Lindberg-Larsen
- The Danish Knee Arthroplasty Register, Denmark; Department of Orthopedic Surgery and Traumatology, Odense University Hospital, Denmark
| | - Alma B Pedersen
- The Danish Knee Arthroplasty Register, Denmark; Department of Clinical Epidemiology, Aarhus University Hospital and Department of Clinical Medicine, Aarhus University, Denmark
| | - Annette W-Dahl
- The Swedish Arthroplasty Register, Sweden; Department of Clinical Sciences Lund, Division of Orthopedics, Lund University, Lund, Sweden
| | - Ola Rolfson
- The Swedish Arthroplasty Register, Sweden; Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Erik Bülow
- Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden; Centre of Registers Västra Götaland, Gothenburg, Sweden
| | | | | | - Rob G H H Nelissen
- The Dutch Arthroplasty Register, the Netherlands; Department of Orthopedics, Leiden University Medical Center, the Netherlands
| | - Dylan Harries
- South Australian Health and Medical Research Institute, Australia
| | - Richard De Steiger
- The Australian Orthopaedic Association National Joint Replacement Registry, Australia
| | - Olav Lutro
- Department of Medicine, Stavanger University Hospital, Norway
| | | | - Keijo Mäkelä
- The Finnish Arthroplasty Register, Finland; Turku University Hospital and University of Turku, Turku, Finland
| | | | | | | | | | | | - Yinan Wu
- The Germany Arthroplasty Registry, Germany
| | - Cristiana Armaroli
- Arthroplasty Registry of the Autonomous Province of Trento (PATN), Clinical Epidemiology Service, Provincial Agency for Health Services of Trento (APSS), Italy
| | - Marco Molinari
- Orthopedics and Traumatology Operative Unit, Cavalese Hospital, Provincial Agency for Health Services of Trento (APSS), Italy
| | - Roberto Picus
- Arthroplasty Register of Autonomous Province of Bolzano (PABZ), Observatory of Health, Health Department AP of Bolzano, Italy
| | | | - Richard Illgen
- American Joint Replacement Registry, USA; University of Wisconsin-Madison School of Medicine and Public Health, Department of Orthopedic Surgery and Rehabilitation, USA
| | - Ioan C Stoica
- Romanian Arthroplasty Registry, Romania; University of Medicine and Pharmacy - Carol Davila - Bucharest - UMFCD Bucharest, Romania; Foisor Orthopedic Hospital, Romania
| | - Andreea E Vorovenci
- Romanian Arthroplasty Registry, Romania; Economic Cybernetics and Statistics Doctoral School, Bucharest University of Economic Studies, Romania
| | - Dan Dragomirescu
- Romanian Arthroplasty Registry, Romania; Economic Cybernetics and Statistics Doctoral School, Bucharest University of Economic Studies, Romania
| | - Håvard Dale
- The Norwegian Arthroplasty Register, Department of Orthopedic Surgery, Haukeland University Hospital, Norway; Department of Clinical Medicine, Faculty of Medicine, University of Bergen, Norway
| | - Christian Brand
- Swiss National Hip & Knee Joint Registry, Switzerland; Institute of Social and Preventive Medicine, SwissRDL, University of Bern; Switzerland
| | - Bernhard Christen
- Swiss National Hip & Knee Joint Registry, Switzerland; Articon, Bern, Switzerland
| | - Joanne Shapiro
- The National Joint Registry for England, Wales, Northern Ireland, The Isle of Man and Guernsey, UK; NEC Software Solutions, Hemel Hempstead, UK
| | - J Mark Wilkinson
- The National Joint Registry for England, Wales, Northern Ireland, The Isle of Man and Guernsey, UK; Department of Oncology and Metabolism, University of Sheffield, Sheffield, UK
| | - Richard Armstrong
- The National Joint Registry for England, Wales, Northern Ireland, The Isle of Man and Guernsey, UK; NEC Software Solutions, Hemel Hempstead, UK
| | - Kate Wooster
- The National Joint Registry for England, Wales, Northern Ireland, The Isle of Man and Guernsey, UK; NEC Software Solutions, Hemel Hempstead, UK
| | - Geir Hallan
- The Norwegian Arthroplasty Register, Department of Orthopedic Surgery, Haukeland University Hospital, Norway; Department of Clinical Medicine, Faculty of Medicine, University of Bergen, Norway
| | - Jan-Erik Gjertsen
- The Norwegian Arthroplasty Register, Department of Orthopedic Surgery, Haukeland University Hospital, Norway; Department of Clinical Medicine, Faculty of Medicine, University of Bergen, Norway
| | - Richard N Chang
- Medical Device Surveillance & Assessment, Kaiser Permanente, USA
| | | | | | - Ove Furnes
- The Norwegian Arthroplasty Register, Department of Orthopedic Surgery, Haukeland University Hospital, Norway; Department of Clinical Medicine, Faculty of Medicine, University of Bergen, Norway
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Hoskins W, Bingham R, Corfield S, Harries D, Harris IA, Vince KG. Do the Revision Rates of Arthroplasty Surgeons Correlate With Postoperative Patient-reported Outcome Measure Scores? A Study From the Australian Orthopaedic Association National Joint Replacement Registry. Clin Orthop Relat Res 2023; 482:00003086-990000000-01237. [PMID: 37339166 PMCID: PMC10723865 DOI: 10.1097/corr.0000000000002737] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [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] [Received: 07/30/2022] [Revised: 03/29/2023] [Accepted: 05/22/2023] [Indexed: 06/22/2023]
Abstract
BACKGROUND Patient-reported outcome measures (PROMs) are a pragmatic and efficient means to evaluate the functional quality of arthroplasty beyond revision rates, which are used by most joint replacement registries to judge success. The relationship between these two measures of quality-revision rates and PROMs-is unknown, and not every procedure with a poor functional result is revised. It is logical-although still untested-that higher cumulative revision rates correlate inversely with PROMs for individual surgeons; more revisions are associated with lower PROM scores. QUESTIONS/PURPOSES We used data from a large national joint replacement registry to ask: (1) Does a surgeon's early THA cumulative percent revision (CPR) rate and (2) early TKA CPR rate correlate with the postoperative PROMs of patients undergoing primary THA and TKA, respectively, who have not undergone revision? METHODS Elective primary THA and TKA procedures in patients with a primary diagnosis of osteoarthritis that were performed between August 2018 and December 2020 and registered in the Australian Orthopaedic Association National Joint Replacement Registry PROMs program were eligible. THAs and TKAs were eligible for inclusion in the primary analysis if 6-month postoperative PROMs were available, the operating surgeon was clearly identified, and the surgeon had performed at least 50 primary THAs or TKAs. Based on the inclusion criteria, 17,668 THAs were performed at eligible sites. We excluded 8878 procedures that were not matched to the PROMs program, leaving 8790 procedures. A further 790 were excluded because they were performed by unknown or ineligible surgeons or were revised, leaving 8000 procedures performed by 235 eligible surgeons, including 4256 (53%; 3744 cases of missing data) patients who had postoperative Oxford Hip Scores and 4242 (53%; 3758 cases of missing data) patients who had a postoperative EQ-VAS score recorded. Complete covariate data were available for 3939 procedures for the Oxford Hip Score and for 3941 procedures for the EQ-VAS. A total of 26,624 TKAs were performed at eligible sites. We excluded 12,685 procedures that were not matched to the PROMs program, leaving 13,939 procedures. A further 920 were excluded because they were performed by unknown or ineligible surgeons, or because they were revisions, leaving 13,019 procedures performed by 276 eligible surgeons, including 6730 (52%; 6289 cases of missing data) patients who had had postoperative Oxford Knee Scores and 6728 (52%; 6291 cases of missing data) patients who had a postoperative EQ-VAS score recorded. Complete covariate data were available for 6228 procedures for the Oxford Knee Score and for 6241 procedures for the EQ-VAS. The Spearman correlation between the operating surgeon's 2-year CPR and 6-month postoperative EQ-VAS Health and Oxford Hip or Oxford Knee Score was evaluated for THA and TKA procedures where a revision had not been performed. Associations between postoperative Oxford and EQ-VAS scores and a surgeon's 2-year CPR were estimated based on multivariate Tobit regressions and a cumulative link model with a probit link, adjusting for patient age, gender, ASA score, BMI category, preoperative PROMs, as well as surgical approach for THA. Missing data were accounted for using multiple imputation, with models assuming they were missing at random and a worst-case scenario. RESULTS Of the eligible THA procedures, postoperative Oxford Hip Score and surgeon 2-year CPR were correlated so weakly as to be clinically irrelevant (Spearman correlation ρ = -0.09; p < 0.001), and the correlation with postoperative EQ-VAS was close to zero (ρ = -0.02; p = 0.25). Of the eligible TKA procedures, postoperative Oxford Knee Score and EQ-VAS and surgeon 2-year CPR were correlated so weakly as to be clinically irrelevant (ρ = -0.04; p = 0.004 and ρ = 0.03; p = 0.006, respectively). All models accounting for missing data found the same result. CONCLUSION A surgeon's 2-year CPR did not exhibit a clinically relevant correlation with PROMs after THA or TKA, and all surgeons had similar postoperative Oxford scores. PROMs, revision rates, or both may be inaccurate or imperfect indicators of successful arthroplasty. Missing data may limit the findings of this study, although the results were consistent under a variety of different missing data scenarios. Innumerable factors contribute to arthroplasty results, including patient-related variables, differences in implant design, and the technical quality of the procedure. PROMs and revision rates may be analyzing two different facets of function after arthroplasty. Although surgeon variables are associated with revision rates, patient factors may exert a stronger influence on functional outcomes. Future research should identify variables that correlate with functional outcome. Additionally, given the gross level of function that Oxford scores record, outcome measures that can identify clinically meaningful functional differences are required. The use of Oxford scores in national arthroplasty registries may rightfully be questioned. LEVEL OF EVIDENCE Level III, therapeutic study.
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Affiliation(s)
- Wayne Hoskins
- Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Parkville, Australia
- Traumaplasty Melbourne, East Melbourne, Australia
- Department of Orthopaedics, Whangarei Hospital, Northland District Health Board, Whangarei, New Zealand
| | | | - Sophia Corfield
- Australian Orthopaedic Association National Joint Replacement Registry, Adelaide, Australia
| | - Dylan Harries
- South Australian Health and Medical Research Institute, Adelaide, Australia
| | - Ian A. Harris
- Australian Orthopaedic Association National Joint Replacement Registry, Adelaide, Australia
- Ingham Institute for Applied Medical Research, School of Clinical Medicine, UNSW Sydney, Australia
| | - Kelly G. Vince
- Department of Orthopaedics, Whangarei Hospital, Northland District Health Board, Whangarei, New Zealand
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Quinn C, O'Kane TJ, Harries D. Systematic calculation of finite-time mixed singular vectors and characterization of error growth for persistent coherent atmospheric disturbances over Eurasia. Chaos 2022; 32:023126. [PMID: 35232053 DOI: 10.1063/5.0066150] [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] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 01/12/2022] [Indexed: 06/14/2023]
Abstract
Singular vectors (SVs) have long been employed in the initialization of ensemble numerical weather prediction (NWP) in order to capture the structural organization and growth rates of those perturbations or "errors" associated with initial condition errors and instability processes of the large scale flow. Due to their (super) exponential growth rates and spatial scales, initial SVs are typically combined empirically with evolved SVs in order to generate forecast perturbations whose structures and growth rates are tuned for specified lead-times. Here, we present a systematic approach to generating finite time or "mixed" SVs (MSVs) based on a method for the calculation of covariant Lyapunov vectors and appropriate choices of the matrix cocycle. We first derive a data-driven reduced-order model to characterize persistent geopotential height anomalies over Europe and Western Asia (Eurasia) over the period 1979-present from the National Centers for Environmental Prediction v1 reanalysis. We then characterize and compare the MSVs and SVs of each persistent state over Eurasia for particular lead-times from a day to over a week. Finally, we compare the spatiotemporal properties of SVs and MSVs in an examination of the dynamics of the 2010 Russian heatwave. We show that MSVs provide a systematic approach to generate initial forecast perturbations projected onto relevant expanding directions in phase space for typical NWP forecast lead-times.
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Affiliation(s)
- Courtney Quinn
- CSIRO Oceans and Atmosphere, Hobart, TAS 7000, Australia
| | | | - Dylan Harries
- CSIRO Oceans and Atmosphere, Hobart, TAS 7000, Australia
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Doktorova M, Harries D, Khelashvili G. Determination of bending rigidity and tilt modulus of lipid membranes from real-space fluctuation analysis of molecular dynamics simulations. Phys Chem Chem Phys 2018. [PMID: 28627570 DOI: 10.1039/c7cp01921a] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
We have recently developed a novel computational methodology (termed RSF for Real-Space Fluctuations) to quantify the bending rigidity and tilt modulus of lipid membranes from real-space analysis of fluctuations in the tilt and splay degrees of freedom as sampled in molecular dynamics (MD) simulations. In this article, we present a comprehensive study that combines results from the application of the RSF method to a wide range of lipid bilayer systems that encompass membranes of different fluidities and sizes, including lipids with saturated and unsaturated lipid tails, single and multi-component lipid systems, as well as non-standard lipids such as the four-tailed cardiolipin. By comparing the material properties calculated with the RSF method to those obtained from experimental data and from other computational methodologies, we rigorously demonstrate the validity of our approach and show its robustness. This should allow for future applications of even more complex lipidic assemblies, whose material properties are not tractable by other computational techniques. In addition, we discuss the relationship between different definitions of the tilt modulus appearing in current literature to address some important unresolved discrepancies in the field.
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Affiliation(s)
- M Doktorova
- Tri-Institutional PhD Program in Computational Biology and Medicine, Weill Cornell Medical College, 1300 York Avenue, New York, NY 10065, USA
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Kenny C, Adhya S, Dworakowski R, Brickham B, Maccarthy P, Monaghan M, Guzzo A, Innocenti F, Vicidomini S, Lazzeretti D, Squarciotta S, De Villa E, Donnini C, Bulletti F, Guerrini E, Pini R, Bendjelid K, Viale J, Duperret S, Piriou V, Jacques D, Shahgaldi K, Silva C, Pedro F, Deister L, Brodin LA, Sahlen A, Manouras A, Winter R, Berjeb N, Cimadevilla C, Dreyfus J, Cueff C, Malanca M, Chiampan A, Vahanian A, Messika-Zeitoun D, Muraru D, Peluso D, Dal Bianco L, Beraldo M, Solda' E, Tuveri M, Cucchini U, Al Mamary A, Badano L, Iliceto S, Almuntaser I, King G, Norris S, Daly C, Ellis E, Murphy R, Erdei T, Denes M, Kardos A, Foldesi C, Temesvari A, Lengyel M, Bouzas Mosquera A, Broullon F, Alvarez-Garcia N, Peteiro J, Barge-Caballero G, Lopez-Perez M, Lopez-Sainz A, Castro-Beiras A, Luotolahti M, Luotolahti H, Kantola I, Viikari J, Andersen M, Ersboell M, Bro-Jeppesen J, Gustafsson F, Koeber L, Hassager C, Moller J, Coisne D, Diakov C, Vallet F, Lequeux B, Blouin P, Christiaens L, Esposito R, Santoro A, Schiano Lomoriello V, Raia R, Santoro C, De Simone G, Galderisi M, Sahlen A, Abdula G, Winter R, Kosmala W, Szczepanik-Osadnik H, Przewlocka-Kosmala M, Mysiak A, O' Moore-Sullivan T, Marwick T, Tan YT, Wenzelburger F, Leyva F, Sanderson J, Pichler P, Syeda B, Hoefer P, Zuckermann A, Binder T, Fijalkowski M, Koprowski A, Galaska R, Blaut K, Sworczak K, Rynkiewicz A, Lee S, Kim W, Jung L, Yun H, Song M, Ko J, Khalifa EA, Szymanski P, Lipczynska M, Klisieiwcz A, Hoffman P, Jorge C, Silva Marques J, Robalo Martins S, Calisto C, Mieiro M, Vieira S, Correia M, Carvalho De Sousa J, Almeida A, Nunes Diogo A, Park C, March K, Tillin T, Mayet J, Chaturvedi N, Hughes A, Di Bello V, Giannini C, Delle Donne M, De Sanctis F, Spontoni P, Cucco C, Corciu A, Grigoratos C, Bogazzi F, Balbarini A, Enescu O, Suran B, Florescu M, Cinteza M, Vinereanu D, Higuchi Y, Iwakura K, Okamura A, Date M, Fujii K, Jorge C, Cortez-Dias N, Silva D, Carrilho-Ferreira P, Silva Marques J, Magalhaes A, Ribeiro S, Goncalves S, Fiuza M, Pinto F, Jorge C, Cortez-Dias N, Silva D, Silva Marques J, Carrilho-Ferreira P, Placido R, Bordalo A, Goncalves S, Fiuza M, Pinto F, Grzywocz P, Mizia-Stec K, Chudek J, Gasior Z, Maceira Gonzalez AM, Cosin Sales J, Dalli E, Igual B, Diago J, Aguilar J, Ruvira J, Cimino S, Pedrizzetti G, Tonti G, Canali E, Petronilli V, Boccalini F, Mattatelli A, Hiramoto Y, Iacoboni C, Agati L, Trifunovic D, Ostojic M, Vujisic-Tesic B, Petrovic M, Nedeljkovic I, Banovic M, Boricic-Kostic M, Draganic G, Tesic M, Petrovic M, Gavina C, Lopes R, Lourenco A, Almeida J, Rodrigues J, Pinho P, Zamorano J, Leite-Moreira A, Rocha-Goncalves F, Clavel MA, Capoulade R, Dumesnil J, Mathieu P, Despres JP, Pibarot P, Bull S, Pitcher A, Augustine D, D'arcy J, Karamitsos T, Rai A, Prendergast B, Becher H, Neubauer S, Myerson S, Magne J, Donal E, Davin L, O'connor K, Pirlet C, Rosca M, Szymanski C, Cosyns B, Pierard L, Lancellotti P, Calin A, Rosca M, Popescu B, Beladan C, Enache R, Lupascu L, Sandu C, Lancellotti P, Pierard L, Ginghina C, Kamperidis V, Hadjimiltiadis S, Sianos G, Anastasiadis K, Grosomanidis V, Efthimiadis G, Karvounis H, Parharidis G, Styliadis I, Gonzalez Canovas C, Munoz-Esparza C, Bonaque Gonzalez J, Fernandez A, Salar Alcaraz M, Saura Espin D, Pinar Bermudez E, Oliva-Sandoval M, De La Morena Valenzuela G, Valdes Chavarri M, Dreyfus J, Brochet E, Lepage L, Attias D, Cueff C, Detaint D, Himbert D, Iung B, Vahanian A, Messika-Zeitoun D, Pirat B, Little S, Chang S, Tiller L, Kumar R, Zoghbi W, Lee APW, Hsiung M, Wan S, Wong R, Luo F, Fang F, Xie J, Underwood M, Sun J, Yu C, Jansen R, Tietge W, Sijbrandij K, Cramer M, De Heer L, Kluin J, Chamuleau SAJ, Oliveras Vila T, Ferrer Sistach E, Delgado Ramis L, Lopez Ayerbe J, Vallejo Camazon N, Gual Capllonch F, Garcia Alonso C, Teis Soley A, Ruyra Baliarda X, Bayes Genis A, Negrea S, Alexandrescu C, Bourlon F, Civaia F, Dreyfus G, Paetzold S, Luha O, Hoedl R, Stoschitzky G, Pfeiffer K, Zweiker D, Pieske B, Maier R, Sevilla T, Revilla A, Lopez J, Vilacosta I, Arnold R, Gomez I, San Roman J, Nikcevic G, Djordjevic Dikic A, Djordjevic S, Raspopovic S, Jovanovic V, Kircanski B, Pavlovic S, Milasinovic G, Ruiz-Zamora I, Cabrera Bueno F, Molina M, Fernandez-Pastor J, Pena J, Linde A, Barrera A, Alzueta J, Bremont C, Bensaid A, Alonso H, Zaghden O, Nahum J, Dubois-Rande J, Gueret P, Lim P, Lee SP, Park K, Kim HR, Lee JH, Ahn HS, Kim JH, Kim HK, Kim YJ, Sohn DW, Niemann M, Herrmann S, Hu K, Liu D, Beer M, Ertl G, Wanner C, Takenaka T, Tei C, Weidemann F, Silva D, Madeira H, Mendes Pedro M, Nunes Diogo A, Brito D, Schiano Lomoriello V, Ippolito R, Santoro A, Esposito R, Raia R, De Palma D, Galderisi M, Gati S, Oxborough D, Reed M, Zaidi A, Ghani S, Sheikh N, Papadakis M, Sharma S, Chow V, Ng A, Pasqualon T, Zhao W, Hanzek D, Chung T, Yeoh T, Kritharides L, Florescu M, Magda L, Enescu O, Mihalcea D, Suran B, Jinga D, Mincu R, Cinteza M, Vinereanu D, Ferrazzi E, Segato G, Folino F, Famoso G, Senzolo M, Bellu R, Corbetti F, Iliceto S, Tona F, Azevedo O, Quelhas I, Guardado J, Fernandes M, Pereira V, Medeiros R, Lourenco A, Sousa P, Santos W, Pereira S, Marques N, Mimoso J, Marques V, Jesus I, Rustad L, Nytroen K, Gullestad L, Amundsen B, Aakhus S, Linhartova K, Sterbakova G, Necas J, Kovalova S, Cerbak R, Nelassov N, Korotkijan N, Shishkina A, Gagieva B, Nagaplev M, Eroshenko O, Morgunov M, Parmon S, Velthuis S, Van Gent M, Post M, Westermann C, Mager J, Snijder R, Koyalakonda SP, Anderson M, Burgess M, Bergenzaun L, Chew M, Ohlin H, Gjerdalen GF, Hisdal J, Solberg E, Andersen T, Radunovic Z, Steine K, Rutz T, Kuehn A, Petzuch K, Pekala M, Elmenhorst J, Fratz S, Mueller J, Hager A, Hess J, Vogt M, Van Der Linde D, Van De Laar I, Wessels M, Bekkers J, Moelker A, Tanghe H, Van Kooten F, Oldenburg R, Bertoli-Avella A, Roos-Hesselink J, Cresti A, Fontani L, Calabria P, Capati E, Severi S, Lynch M, Saraf S, Sandler B, Yoon S, Kim S, Ko C, Ryu S, Byun Y, Seo H, Ciampi Q, Rigo F, Pratali L, Gherardi S, Villari B, Picano E, Sicari R, Celutkiene J, Zakarkaite D, Skorniakov V, Zvironaite V, Grabauskiene V, Sinicyna J, Gruodyte G, Janonyte K, Laucevicius A, O'driscoll J, Schmid K, Marciniak A, Saha A, Gupta S, Smith R, Sharma R, Bouzas Mosquera A, Alvarez Garcia N, Peteiro J, Broullon F, Prada O, Rodriguez Vilela A, Barge Caballero G, Lopez Perez M, Lopez Sainz A, Castro Beiras A, Kochanowski J, Scislo P, Piatkowski R, Grabowski M, Marchel M, Roik M, Kosior D, Opolski G, Van De Heyning CM, Magne J, O'connor K, Mahjoub H, Pibarot P, Pirlet C, Pierard L, Lancellotti P, Clausen H, Basaggianis C, Newton J, Del Pasqua A, Carotti A, Di Carlo D, Cetrano E, Toscano A, Iacobelli R, Esposito C, Chinali M, Pongiglione G, Rinelli G, Larsson M, Larsson M, Bjallmark A, Winter R, Caidahl K, Brodin L, Velthuis S, Van Gent M, Mager J, Westermann C, Snijder R, Post M, Gao H, Coisne D, Lugiez M, Guivier C, Rieu R, D'hooge J, Lugiez M, Hang G, D'hooge J, Guerin C, Christiaens L, Menard M, Voigt JU, Coisne D, Dungu J, Campos G, Jaffarulla R, Gomes-Pereira S, Sutaria N, Baker C, Nihoyannopoulos P, Bellamy M, Adhya S, Harries D, Walker N, Pearson P, Reiken J, Batteson J, Kamdar R, Murgatroyd F, Monaghan M, D'andrea A, Riegler L, Scarafile R, Pezzullo E, Salerno G, Bossone E, Limongelli G, Russo M, Pacileo G, Calabro' R, Kang Y, Cui J, Chen H, Pan C, Shu X, Kiotsekoglou A, Saha S, Toole R, Govind S, Gopal A, Crispi F, Bijnens B, Sepulveda-Swatson E, Rojas-Benavente J, Dominguez J, Illa M, Eixarch E, Sitges M, Gratacos E, Prinz C, Faludi R, Walker A, Amzulescu M, Gao H, Uejima T, Fraser A, Voigt J, Esmaeilzadeh M, Maleki M, Amin A, Vakilian F, Noohi F, Ojaghi Haghighi Z, Nakhostin Davari P, Bakhshandeh Abkenar H, Rimbas R, Dulgheru R, Margulescu A, Florescu M, Vinereanu D, Toscano A, Chinali M, D' Asaro M, Iacobelli R, Del Pasqua A, Esposito C, Mizzon C, Parisi F, Pongiglione G, Rinelli G, Jung BC, Lee BY, Kang HJ, Kim S, Kim M, Kim Y, Cho D, Park S, Hong S, Lim D, Shim W, Bellsham-Revell H, Tibby S, Bell AJ, Miller OI, Greil G, Simpson JM, Providencia RA, Trigo J, Botelho A, Gomes P, Seca L, Barra S, Faustino A, Costa G, Quintal N, Leitao-Marques A, Nestaas E, Stoylen A, Fugelseth D, Mornos C, Ionac A, Petrescu L, Cozma D, Dragulescu D, Mornos A, Pescariu S, Fontana A, Abbate M, Cazzaniga M, Giannattasio C, Trocino G, Laser K, Faber L, Fischer M, Koerperich H, Kececioglu D, Elnoamany MF, Dawood A, Elhabashy M, Khalil Y, Fontana A, Abbate M, Cazzaniga M, Giannattasio C, Trocino G, Piriou N, Warin-Fresse K, Caza M, Fau G, Crochet D, Xhabija N, Allajbeu I, Petrela E, Heba M, Barreiro Perez M, Martin Fernandez M, Renilla Gonzalez A, Florez Munoz J, Fernandez Cimadevilla O, Alvarez Pichel I, Velasco Alonso E, Leon Duran D, Benito Martin E, Secades Gonzalez S, Gargani L, Pang P, Davis E, Schumacher A, Sicari R, Picano E, Silva Ferreira A, Bettencourt N, Matos P, Oliveira L, Almeida A, Maceira Gonzalez AM, Cosin-Sales J, Igual B, Lopez Lereu M, Monmeneu J, Estornell J, Tsverava M, Tsverava D, Varela A, Salagianni M, Galani I, Andreakos E, Davos C, Ikonomidis I, Lekakis J, Tritakis V, Kadoglou N, Papadakis J, Trivilou P, Tzortzis S, Koukoulis C, Paraskevaidis I, Anastasiou-Nana M, Kim G, Youn H, Park C, Ibrahimi P, Bajraktari G, Jashari F, Ahmeti A, Poniku A, Haliti E, Henein M, Pezo Nikolic B, Jurin H, Lovric D, Baricevic Z, Ivanac Vranesic I, Lovric Bencic M, Ernst A, Separovic Hanzevacki J. Poster Session 3: Friday 9 December 2011, 08:30-12:30 * Location: Poster Area. European Journal of Echocardiography 2011. [DOI: 10.1093/ejechocard/jer214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Guldbrand D, Goetzsche O, Eika B, Watanabe N, Taniguchi M, Akagi T, Koide N, Sano S, Orbovic B, Obrenovic-Kircanski B, Ristic S, Soskic LJ, Alhabshan F, Jijeh A, Abo Remsh H, Alkhaldi A, Najm HK, Gasior Z, Skowerski M, Kulach A, Szymanski L, Sosnowski M, Wang M, Siu CW, Lee K, Yue WS, Yan GH, Lee S, Lau CP, Tse HF, O'connor K, Rosca M, Magne J, Romano G, Moonen M, Pierard LA, Lancellotti P, Floria M, De Roy L, Blommaert D, Jamart J, Dormal F, Lacrosse M, Arsenescu Georgescu C, Mizariene V, Bucyte S, Bertasiute A, Pociute E, Zaliaduonyte-Peksiene D, Baronaite-Dudoniene K, Sileikiene R, Vaskelyte J, Jurkevicius R, Dencker M, Thorsson O, Karlsson MK, Linden C, Wollmer P, Andersen LB, Catalano O, Perotti MR, Colombo E, De Giorgi M, Cattaneo M, Cobelli F, Priori SG, Ober C, Iancu Adrian IA, Andreea Parv PA, Cadis Horatiu CH, Ober Mihai OM, Chmielecki M, Fijalkowski M, Galaska R, Dubaniewicz W, Lewicki L, Targonski R, Ciecwierz D, Puchalski W, Koprowski A, Rynkiewicz A, Hristova K, La Gerche A, Katova TZ, Kostova V, Simova Y, Kempny A, Diller GP, Orwat S, Kaleschke G, Kerckhoff G, Schmidt R, Radke RM, Baumgartner H, Smarz K, Zaborska B, Jaxa-Chamiec T, Maciejewski P, Budaj A, Kiotsekoglou A, Govind SC, Gadiyaram V, Moggridge JC, Govindan M, Gopal AS, Ramesh SS, Brodin LA, Saha SK, Ramzy IS, Lindqvist P, Lam YY, Duncan AM, Henein MY, Craciunescu IS, Serban M, Iancu M, Revnic C, Popescu BA, Alexandru D, Rogoz D, Uscatescu V, Ginghina C, Careri G, Di Monaco A, Nerla R, Tarzia P, Lamendola P, Sestito A, Lanza GA, Crea F, Giannini F, Pinamonti B, Santangelo S, Perkan A, Vitrella G, Rakar S, Merlo M, Della Grazia E, Salvi A, Sinagra G, Scislo P, Kochanowski J, Piatkowski R, Roik M, Postula M, Opolski G, Castillo J, Herszkowicz N, Ferreira C, Lonnebakken MT, Staal EM, Nordrehaug JE, Gerdts E, Przewlocka-Kosmala M, Orda A, Karolko B, Bajraktari G, Lindqvist P, Gustafsson U, Holmgren A, Henein MY, Frattini S, Faggiano P, Zilioli V, Locantore E, Longhi S, Bellandi F, Faden G, Triggiani M, Dei Cas L, Seo SM, Jung HO, An SH, Jung SY, Park CS, Jeon HK, Youn HJ, Chung WB, Kim JH, Uhm JS, Mampuya W, Brochu MC, Do DH, Essadiqi B, Farand P, Lepage S, Daly MJ, Monaghan M, Hamilton A, Lockhart C, Kodoth V, Maguire C, Morton A, Manoharan G, Spence MS, Streb W, Mitrega K, Nowak J, Duszanska A, Szulik M, Kalinowski M, Kukulski T, Kalarus Z, Calvo Iglesias FE, Solla-Ruiz I, Villanueva-Benito I, Paredes-Galan E, Bravo-Amaro M, Iniguez-Romo A, Yildirimturk O, Helvacioglu FF, Tayyareci Y, Yurdakul S, Demiroglu IC, Aytekin S, Enache R, Piazza R, Muraru D, Roman-Pognuz A, Popescu BA, Calin A, Leiballi E, Antonini-Canterin F, Ginghina C, Nicolosi GL, Ridard C, Bellouin A, Thebault C, Laurent M, Donal E, Sutandar A, Siswanto BB, Irmalita I, Harimurti G, Saxena A, Ramakrishnan S, Roy A, Krishnan A, Misra P, Bhargava B, Poole-Wilson PA, Loegstrup BB, Andersen HR, Poulsen SH, Klaaborg KE, Egeblad HE, Gu X, Gu XY, He YH, Li ZA, Han JC, Chen J, Mansencal N, Mitry E, Rougier P, Dubourg O, Villarraga H, Adjei-Twum K, Cudjoe TKM, Clavell A, Schears RM, Cabrera Bueno F, Molina Mora MJ, Fernandez Pastor J, Linde Estrella A, Pena Hernandez JL, Isasti Aizpurua G, Carrasco Chinchilla F, Barrera Cordero A, Alzueta Rodriguez FJ, De Teresa Galvan E, Gaetano Contegiacomo GC, Francesco Pollice FP, Paolo Pollice PP, Gu X, Gu XY, He YH, Li ZA, Kontos MC, Shin DH, Yoo SY, Lee CK, Jang JK, Jung SI, Song SI, Seo SI, Cheong SS, Peteiro J, Perez-Perez A, Bouzas-Mosquera A, Pineiro M, Pazos P, Campo R, Castro-Beiras A, Gaibazzi N, Rigo F, Sartorio D, Reverberi C, Sitia S, Tomasoni L, Gianturco L, Ghio L, Stella D, Greco P, De Gennaro Colonna V, Turiel M, Sitia S, Tomasoni L, Cicala S, Magagnin V, Caiani E, Turiel M, Kyrzopoulos S, Tsiapras D, Domproglou G, Avramidou E, Voudris V, Wierzbowska-Drabik K, Lipiec P, Chrzanowski L, Roszczyk N, Kupczynska K, Kasprzak JD, Sachpekidis V, Bhan A, Gianstefani S, Reiken J, Paul M, Pearson P, Harries D, Monaghan MJ, Dale K, Stoylen A, Saha SK, Kodali V, Toole R, Govind SC, Moggridge JC, Kiotsekoglou A, Gopal AS, Raju P, Mcintosh RA, Silberbauer J, Baumann O, Patel NR, Sulke N, Trivedi U, Hyde J, Venn G, Lloyd G, Wejner-Mik P, Lipiec P, Wierzbowska K, Kasprzak JD, Lowenstein JA, Caniggia C, Garcia A, Amor M, Casso N, Lowenstein Haber D, Porley C, Zambrana G, Daru V, Deljanin Ilic M, Ilic S, Kalimanovska Ostric D, Stoickov V, Zdravkovic M, Paraskevaidis I, Ikonomidis I, Parissis J, Papadopoulos C, Stasinos V, Bistola V, Anastasiou-Nana M, Gudin Uriel M, Balaguer Malfagon JR, Perez Bosca JL, Ridocci Soriano F, Martinez Alzamora N, Paya Serrano R, Ciampi Q, Pratali L, Della Porta M, Petruzziello B, Villari B, Picano E, Sicari R, Rosner A, Avenarius D, Malm S, Iqbal A, Baltabaeva A, Sutherland GR, Bijnens B, Myrmel T, Andersen M, Gustafsson F, Secher NH, Brassard P, Jensen AS, Hassager C, Madsen PL, Moller JE, Mampuya W, Brochu MC, Coutu M, Do DH, Essadiqi B, Farand P, Greentree D, Normandin D, Lepage S, Brun H, Dipchand A, Koopman L, Fackoury CT, Truong S, Manlhiot C, Mertens L, Baroni M, Mariani M, Chabane HK, Berti S, Ripoli A, Storti S, Glauber M, Scopelliti PA, Antongiovanni GB, Personeni D, Saino A, Tespili M, Jung P, Mueller M, Jander F, Sohn HY, Rieber J, Schneider P, Klauss V, Agricola E, Slavich M, Stella S, Ancona M, Oppizzi M, Bertoglio L, Melissano G, Margonato A, Chiesa R, Cejudo Diaz Del Campo L, Mesa Rubio D, Ruiz Ortiz M, Delgado Ortega M, Villanueva Fernandez E, Lopez Aguilera J, Toledano Delgado F, Pan Alvarez-Ossorio M, Suarez De Lezo Cruz Conde J, Lafuente M, Butz T, Meissner A, Lang CN, Prull MW, Plehn G, Trappe HJ, Nair SV, Lee L, Mcleod I, Whyte G, Shrimpton J, Hildick Smith D, James PR, Slikkerveer J, Appelman YEA, Veen G, Porter TR, Kamp O, Colonna P, Ten Cate FJ, Bokor D, Daponte A, Cocciolo M, Bona M, Sacchi S, Becher H, Chai SC, Tan PJ, Goh YS, Ong SH, Chow J, Lee LL, Goh PP, Tong KL, Kakihara R, Naruse C, Hironaka H, Tsuzuku T, Ozawa K, Tomaszuk-Kazberuk A, Sobkowicz B, Malyszko J, Malyszko JS, Kalinowski M, Sawicki R, Hirnle T, Dobrzycki S, Mysliwiec M, Musial WJ, Mathias W, Kowatsch I, Saroute ALR, Osorio AFF, Sbano JCN, Ramires JAF, Tsutsui JM, Sakata K, Ito H, Ishii K, Sakuma T, Iwakura K, Yoshino H, Yoshikawa J, Shahgaldi K, Lopez A, Fernstrom B, Sahlen A, Winter R, Kovalova S, Necas J, Amundsen BH, Jasaityte R, Kiss G, Barbosa D, D'hooge J, Torp H, Szmigielski CA, Newton JD, Rajpoot K, Noble JA, Kerber R, Becher H, Koopman LP, Slorach C, Chahal N, Hui W, Sarkola T, Manlhiot C, Bradley TJ, Jaeggi ET, Mccrindle BW, Mertens L, Staron A, Gasior Z, Jasinski M, Wos S, Sengupta P, Wierzbowska-Drabik K, Chrzanowski L, Kasprzak JD, Hayat D, Kloeckner M, Nahum J, Dussault C, Dubois Rande JL, Gueret P, Lim P, King GJ, Brown A, Ho E, Amuntaser I, Bennet K, Mc Elhome N, Murphy RT, Cooper RM, Somauroo JD, Shave RE, Williams KL, Forster J, George C, Bett T, George KP, D'andrea A, Riegler L, Cocchia R, Golia E, Gravino R, Salerno G, Citro R, Caso PIO, Bossone E, Calabro' R, Crispi F, Bijnens B, Figueras F, Bartrons J, Eixarch E, Le Noble F, Ahmed A, Gratacos E, Shang Q, Yip WK, Tam LS, Zhang Q, Lam YY, Li CM, Wang T, Ma CY, Li KM, Yu CM, Dahlslett T, Helland I, Edvardsen T, Skulstad H, Magda LS, Florescu M, Ciobanu A, Dulgheru R, Mincu R, Vinereanu D, Luckie M, Chacko S, Nair S, Mamas M, Khattar RS, El-Omar M, Kuch-Wocial A, Pruszczyk P, Szmigielski CA, Szulc M, Styczynski G, Sinski M, Kaczynska A, Bajraktari G, Vela Z, Haliti E, Hyseni V, Olloni R, Rexhepaj N, Elezi S, Henein MY, Onaindia JJ, Quintana O, Cacicedo A, Velasco S, Alarcon JJ, Morillas M, Rumoroso JR, Zumalde J, Lekuona I, Laraudogoitia Zaldumbide E, Haliti E, Bajraktari G, Poniku A, Ahmeti A, Elezi S, Henein MY, Duncan RF, Mccomb JM, Pemberton J, Lord SW, Leong D, Plummer C, Macgowan G, Grubb N, Leung M, Kenny A, Prinz C, Voigt JU, Zaidi A, Heatley M, Abildstrom SZ, Hvelplund A, Berning J, Saha SK, Toole R, Govind S, Kiotsekoglou A, Brodin L, Gopal A, Castaldi B, Di Salvo G, Santoro G, Gaio G, Palladino MT, Iacono C, Pacileo G, Russo MG, Calabro R, Wang YS, Dong LL, Shu XH, Pan CZ, Zhou DX, Sen T, Tufekcioglu O, Ozdemir M, Tuncez A, Uygur B, Golbasi Z, Kisacik H, Delfino L, De Leo FD, Chiappa LC, Abdel Ghani B, Schiavina R, Salvade P, Morganti A, Bedogni F, Mahia P, Gutierrez L, Pineda V, Garcia B, Otaegui I, Rodriguez JF, Gonzalez MT, Descalzo M, Evangelista A, Garcia-Dorado D, Bruin De- Bon HACM, Van Den Brink RBA, Surie S, Bresser P, Vleugels J, Eckmann HM, Samson DA, Bouma BJ, Dedobbeleer C, Antoine M, Remmelink M, Unger P, Roosens B, Hmila I, Hernot S, Droogmans S, Van Camp G, Lahoutte T, Muyldermans S, Cosyns B, Feltes G, Serra V, Azevedo O, Barbado J, Herrera J, Rivera A, Paniagua J, Valverde V, Torras J, Arriba G, Christodoulides T, Ioannides M, Simamonian K, Yiangou K, Myrianthefs M, Nicolaides E, Dedobbeleer C, Pandolfo M, Unger P, Kleijn SA, Aly MFAA, Terwee CB, Van Rossum AC, Kamp O, Delgado V, Shanks M, Siebelink HM, Sieders A, Lamb H, Ajmone Marsan N, Westenberg J, De Roos A, Schuijf JD, Bax JJ, Anwar AM, Nosir Y, Chamsi-Pasha H, Tschernich HD, Seeburger J, Borger M, Mukherjee C, Mohr FW, Ender J, Obase K, Okura H, Yamada R, Miyamoto Y, Saito K, Imai K, Hayashida A, Watanabe N, Yoshida K. Poster session III * Friday 10 December 2010, 08:30-12:30. European Journal of Echocardiography 2010. [DOI: 10.1093/ejechocard/jeq144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Sachpekidis V, Bhan A, Paul M, Gianstefani S, Smith L, Reiken J, Walker N, Harries D, Pearson P, Monaghan MJ. The additive value of three-dimensional derived left atrial volume and carotid imaging in dobutamine stress echocardiography. European Journal of Echocardiography 2010; 12:46-53. [DOI: 10.1093/ejechocard/jeq104] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Ringer D, Harries D. Stoffstrommodellierung und CO 2-Neutralität - ein Widerspruch? CHEM-ING-TECH 2008. [DOI: 10.1002/cite.200750560] [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: 11/12/2022]
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Abstract
The adsorption free energy of charged proteins on mixed membranes, containing varying amounts of (oppositely) charged lipids, is calculated based on a mean-field free energy expression that accounts explicitly for the ability of the lipids to demix locally, and for lateral interactions between the adsorbed proteins. Minimization of this free energy functional yields the familiar nonlinear Poisson-Boltzmann equation and the boundary condition at the membrane surface that allows for lipid charge rearrangement. These two self-consistent equations are solved simultaneously. The proteins are modeled as uniformly charged spheres and the (bare) membrane as an ideal two-dimensional binary mixture of charged and neutral lipids. Substantial variations in the lipid charge density profiles are found when highly charged proteins adsorb on weakly charged membranes; the lipids, at a certain demixing entropy penalty, adjust their concentration in the vicinity of the adsorbed protein to achieve optimal charge matching. Lateral repulsive interactions between the adsorbed proteins affect the lipid modulation profile and, at high densities, result in substantial lowering of the binding energy. Adsorption isotherms demonstrating the importance of lipid mobility and protein-protein interactions are calculated using an adsorption equation with a coverage-dependent binding constant. Typically, at bulk-surface equilibrium (i.e., when the membrane surface is "saturated" by adsorbed proteins), the membrane charges are "overcompensated" by the protein charges, because only about half of the protein charges (those on the hemispheres facing the membrane) are involved in charge neutralization. Finally, it is argued that the formation of lipid-protein domains may be enhanced by electrostatic adsorption of proteins, but its origin (e.g., elastic deformations associated with lipid demixing) is not purely electrostatic.
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Affiliation(s)
- S May
- Institut für Biochemie und Biophysik, Friedrich-Schiller-Universität Jena, Philosophenweg 12, 07743 Jena, Germany
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Abstract
We present a theoretical analysis of the phase behavior of solutions containing DNA, cationic lipids, and nonionic (helper) lipids. Our model allows for five possible structures, treated as incompressible macroscopic phases: two lipid-DNA composite (lipoplex) phases, namely, the lamellar (L(alpha)(C)) and hexagonal (H(II)(C)) complexes; two binary (cationic/neutral) lipid phases, that is, the bilayer (L(alpha)) and inverse-hexagonal (H(II)) structures, and uncomplexed DNA. The free energy of the four lipid-containing phases is expressed as a sum of composition-dependent electrostatic, elastic, and mixing terms. The electrostatic free energies of all phases are calculated based on Poisson-Boltzmann theory. The phase diagram of the system is evaluated by minimizing the total free energy of the three-component mixture with respect to all the compositional degrees of freedom. We show that the phase behavior, in particular the preferred lipid-DNA complex geometry, is governed by a subtle interplay between the electrostatic, elastic, and mixing terms, which depend, in turn, on the lipid composition and lipid/DNA ratio. Detailed calculations are presented for three prototypical systems, exhibiting markedly different phase behaviors. The simplest mixture corresponds to a rigid planar membrane as the lipid source, in which case, only lamellar complexes appear in solution. When the membranes are "soft" (i.e., low bending modulus) the system exhibits the formation of both lamellar and hexagonal complexes, sometimes coexisting with each other, and with pure lipid or DNA phases. The last system corresponds to a lipid mixture involving helper lipids with strong propensity toward the inverse-hexagonal phase. Here, again, the phase diagram is rather complex, revealing a multitude of phase transitions and coexistences. Lamellar and hexagonal complexes appear, sometimes together, in different regions of the phase diagram.
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Affiliation(s)
- S May
- Department of Physical Chemistry and the Fritz Haber Research Center, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
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Abstract
Under a wide variety of conditions, the addition of condensing agents to dilute solutions of random-coil DNA gives rise to highly compact particles that are toroidal in shape. The size of these condensates is remarkably constant and is largely independent of DNA molecular weight and basepair sequence, and of the nature of condensing agent (e.g., multivalent cation, polymers, or added cosolvent). We show how this optimum size is determined by the interactions between topological defects, which unavoidably strain the circumferentially wound DNA strands in the torus.
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Affiliation(s)
- S Y Park
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569 USA.
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Abstract
We develop a statistical thermodynamic model for the phase evolution of DNA-cationic lipid complexes in aqueous solution, as a function of the ratios of charged to neutral lipid and charged lipid to DNA. The complexes consist of parallel strands of DNA intercalated in the water layers of lamellar stacks of mixed lipid bilayers, as determined by recent synchrotron x-ray measurements. Elastic deformations of the DNA and the lipid bilayers are neglected, but DNA-induced spatial inhomogeneities in the bilayer charge densities are included. The relevant nonlinear Poisson-Boltzmann equation is solved numerically, including self-consistent treatment of the boundary conditions at the polarized membrane surfaces. For a wide range of lipid compositions, the phase evolution is characterized by three regions of lipid to DNA charge ratio, rho: 1) for low rho, the complexes coexist with excess DNA, and the DNA-DNA spacing in the complex, d, is constant; 2) for intermediate rho, including the isoelectric point rho = 1, all of the lipid and DNA in solution is incorporated into the complex, whose inter-DNA distance d increases linearly with rho; and 3) for high rho, the complexes coexist with excess liposomes (whose lipid composition is different from that in the complex), and their spacing d is nearly, but not completely, independent of rho. These results can be understood in terms of a simple charging model that reflects the competition between counterion entropy and inter-DNA (rho < 1) and interbilayer (rho > 1) repulsions. Finally, our approach and conclusions are compared with theoretical work by others, and with relevant experiments.
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Affiliation(s)
- D Harries
- Department of Physical Chemistry and the Fritz Haber Research Center, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
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White A, Harries D, Allen SC. Anorexia nervosa in the elderly: a case report and review of the literature. Br J Clin Pract 1990; 44:630-1. [PMID: 2102162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Anorexia nervosa is a rare disorder in the elderly but should be thought of in the differential diagnosis of extreme weight loss, especially if there are accompanying psychological features and normal baseline investigations. Psychiatric opinion should be obtained and treatment, although of unproven value, considered, since improvement may increase mobility and reduce morbidity and mortality.
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Affiliation(s)
- A White
- Department of Medicine for the Elderly, Christchurch Hospital, Dorset
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Abstract
The effects of temperatures of 50 to 60 C on suspensions of a strain of Escherichia coli are described. At these temperatures, the substances which leaked from the cells were determined as pentoses; the amount leaked over a 30-min period increased with increasing temperature. The leakage materials from suspensions heated in water, sodium chloride, sucrose, and sucrose plus Mg(++) were examined spectrophotometrically, and the ratios of the absorbances at 280 and 260 nm (the 280 to 260 nm ratio) were determined. It was not possible to determine protein by this method, as the ratio was always <0.7. When saline was the suspending medium, the ratio was lower than when water was used, and there was a greater leakage of 260 nm absorbing material. When suspended in sucrose or in sucrose plus Mg(++), penicillin-induced spheroplasts did not undergo lysis, but became less regular in shape, and there was an increase in the extinction at 500 nm. The overall effects of high temperatures on nonsporeforming bacterial cells are discussed; in view of the available evidence, it is concluded that ribonucleic acid degradation is an event which is probably closely related to thermally induced bacterial death.
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Abstract
Maximal revival of heat-damaged Escherichia coli occurred in nutrient media containing 0.8 to 1.0% (w/v) of Difco yeast extract. Vitamins did not appear to be involved in the recovery process. The situation with amino acids was less clear-cut, and, although certain of these may be essential for revival, proof for this is as yet inconclusive. Replica plating, in which colonies (from cells which had survived a heating process) on a rich medium were replicated onto minimal agar, revealed that no auxotrophic mutants had been formed as a result of heat treatment. Bacteria which were heated in 1% (w/v) yeast extract were killed more slowly than those heated in water.
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Abstract
Abstract
Suspensions of Escherichia coli in water at 50, 55, 60 and 100° showed an increase in extinction and nephelometer readings, the rate of increase depending on the temperature. This is considered to represent varying degrees of alteration in bacterial cytoplasmic protein. No such increases at any temperature occurred with cells held in 0.9% w/v sodium chloride. Lysozyme induced no lysis in cells which had been heated in water or in saline.
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Abstract
The effects of different temperatures on the viability of, and leakage of 260 mmu-absorbing substances from, a strain of Escherichia coli have been studied. Results of experiments with suspensions stored in water and in 0.33 m sucrose, together with total counts of suspensions before and after heating, suggested that the initial damage inflicted on the cell was to the permeability barrier. However, it was concluded that the evidence presently available for supporting this hypothesis is inadequate.
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Harries D, Russell AD. The influence of sodium chloride on the revival of heat-treated Escherichia coli. Lab Pract 1966; 15:859-60. [PMID: 5329554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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