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Chakrabarty G, NaveenKumar SK, Kumar S, Mugesh G. Modulation of Redox Signaling and Thiol Homeostasis in Red Blood Cells by Peroxiredoxin Mimetics. ACS Chem Biol 2020; 15:2673-2682. [PMID: 32915529 DOI: 10.1021/acschembio.0c00309] [Citation(s) in RCA: 4] [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] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Red blood cell death or erythrocyte apoptosis (eryptosis) is generally mediated by oxidative stress, energy depletion, heavy metals exposure, or xenobiotics. As erythrocytes are a major target for oxidative stress due to their primary function as O2-carrying cells, they possess an efficient antioxidant defense system consisting of glutathione peroxidase (GPx), superoxide dismutase (SOD), catalase (CAT), and peroxiredoxin 2 (Prx2). The oxidative stress-mediated activation of the Ca2+-permeable cation channel results in Ca2+ entry into the cells and subsequent cell death. Herein, we describe for the first time that selenium compounds having intramolecular diselenide or selenenyl sulfide moieties can prevent the oxidative stress-induced eryptosis by exhibiting an unusual Prx2-like redox activity under conditions when the cellular Prx2 and CAT enzymes are inhibited.
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Affiliation(s)
- Gaurango Chakrabarty
- Department of Inorganic and Physical Chemistry, Indian Institute of Science Bangalore 560012, India
| | | | - Sagar Kumar
- Department of Inorganic and Physical Chemistry, Indian Institute of Science Bangalore 560012, India
| | - Govindasamy Mugesh
- Department of Inorganic and Physical Chemistry, Indian Institute of Science Bangalore 560012, India
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Arai K, Matsunaga T, Ueno H, Akahoshi N, Sato Y, Chakrabarty G, Mugesh G, Iwaoka M. Modeling Thioredoxin Reductase-Like Activity with Cyclic Selenenyl Sulfides: Participation of an NH⋅⋅⋅Se Hydrogen Bond through Stabilization of the Mixed Se-S Intermediate. Chemistry 2019; 25:12751-12760. [PMID: 31390113 DOI: 10.1002/chem.201902230] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [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: 05/15/2019] [Revised: 06/20/2019] [Indexed: 01/22/2023]
Abstract
At the redox-active center of thioredoxin reductase (TrxR), a selenenyl sulfide (Se-S) bond is formed between Cys497 and Sec498, which is activated into the thiolselenolate state ([SH,Se- ]) by reacting with a nearby dithiol motif ([SHCys59 ,SHCys64 ]) present in the other subunit. This process is achieved through two reversible steps: an attack of a cysteinyl thiol of Cys59 at the Se atom of the Se-S bond and a subsequent attack of a remaining thiol at the S atom of the generated mixed Se-S intermediate. However, it is not clear how the kinetically unfavorable second step progresses smoothly in the catalytic cycle. A model study that used synthetic selenenyl sulfides, which mimic the active site structure of human TrxR comprising Cys497, Sec498, and His472, suggested that His472 can play a key role by forming a hydrogen bond with the Se atom of the mixed Se-S intermediate to facilitate the second step. In addition, the selenenyl sulfides exhibited a defensive ability against H2 O2 -induced oxidative stress in cultured cells, which suggests the possibility for medicinal applications to control the redox balance in cells.
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Affiliation(s)
- Kenta Arai
- Department of Chemistry, School of Science, Tokai University, Kitalaname, Hiratsuka-shi, Kanagawa, 259-1292, Japan
| | - Takahiko Matsunaga
- Department of Chemistry, School of Science, Tokai University, Kitalaname, Hiratsuka-shi, Kanagawa, 259-1292, Japan
| | - Haruhito Ueno
- Department of Chemistry, School of Science, Tokai University, Kitalaname, Hiratsuka-shi, Kanagawa, 259-1292, Japan
| | - Nozomi Akahoshi
- Department of Chemistry, School of Science, Tokai University, Kitalaname, Hiratsuka-shi, Kanagawa, 259-1292, Japan
| | - Yuumi Sato
- Department of Chemistry, School of Science, Tokai University, Kitalaname, Hiratsuka-shi, Kanagawa, 259-1292, Japan
| | - Gaurango Chakrabarty
- Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore, 560012, India
| | - Govindasamy Mugesh
- Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore, 560012, India
| | - Michio Iwaoka
- Department of Chemistry, School of Science, Tokai University, Kitalaname, Hiratsuka-shi, Kanagawa, 259-1292, Japan
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Arai K, Matsunaga T, Ueno H, Akahoshi N, Sato Y, Chakrabarty G, Mugesh G, Iwaoka M. Cover Feature: Modeling Thioredoxin Reductase‐Like Activity with Cyclic Selenenyl Sulfides: Participation of an NH⋅⋅⋅Se Hydrogen Bond through Stabilization of the Mixed Se−S Intermediate (Chem. Eur. J. 55/2019). Chemistry 2019. [DOI: 10.1002/chem.201903073] [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: 11/09/2022]
Affiliation(s)
- Kenta Arai
- Department of ChemistrySchool of ScienceTokai University, Kitalaname, Hiratsuka-shi Kanagawa 259-1292 Japan
| | - Takahiko Matsunaga
- Department of ChemistrySchool of ScienceTokai University, Kitalaname, Hiratsuka-shi Kanagawa 259-1292 Japan
| | - Haruhito Ueno
- Department of ChemistrySchool of ScienceTokai University, Kitalaname, Hiratsuka-shi Kanagawa 259-1292 Japan
| | - Nozomi Akahoshi
- Department of ChemistrySchool of ScienceTokai University, Kitalaname, Hiratsuka-shi Kanagawa 259-1292 Japan
| | - Yuumi Sato
- Department of ChemistrySchool of ScienceTokai University, Kitalaname, Hiratsuka-shi Kanagawa 259-1292 Japan
| | - Gaurango Chakrabarty
- Department of Inorganic and Physical ChemistryIndian Institute of Science Bangalore 560012 India
| | - Govindasamy Mugesh
- Department of Inorganic and Physical ChemistryIndian Institute of Science Bangalore 560012 India
| | - Michio Iwaoka
- Department of ChemistrySchool of ScienceTokai University, Kitalaname, Hiratsuka-shi Kanagawa 259-1292 Japan
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Das R, Bharati SP, Borborah A, Sarma PJ, Das B, Choudhury S, Chakrabarty G, Mahanta SP. A Cu(ii) mediated approach for colorimetric detection of aqueous fluoride in ppm level with a Schiff base receptor. NEW J CHEM 2018. [DOI: 10.1039/c8nj00331a] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Inspired by the importance of fluoride detection in aqueous environment, a new methodology is demonstrated by employing the synergistic reaction of fluoride and Cu(ii) salts with a designed Schiff base receptor.
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Affiliation(s)
- Rituraj Das
- Department of Chemical Sciences, Tezpur University
- Tezpur 784 028
- India
| | | | - Abhishek Borborah
- Department of Chemical Sciences, Tezpur University
- Tezpur 784 028
- India
| | - Plaban J. Sarma
- Department of Chemical Sciences, Tezpur University
- Tezpur 784 028
- India
| | - Bhargab Das
- Department of Chemical Sciences, Tezpur University
- Tezpur 784 028
- India
| | | | - Gaurango Chakrabarty
- Department of Inorganic and Physical Chemistry, Indian Institute of Science
- Bangalore
- India
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Arai K, Ueno H, Asano Y, Chakrabarty G, Shimodaira S, Mugesh G, Iwaoka M. Protein Folding in the Presence of Water-Soluble Cyclic Diselenides with Novel Oxidoreductase and Isomerase Activities. Chembiochem 2017; 19:207-211. [PMID: 29197144 DOI: 10.1002/cbic.201700624] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [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: 11/27/2017] [Indexed: 01/29/2023]
Abstract
The protein disulfide isomerase (PDI) family, found in the endoplasmic reticulum (ER) of the eukaryotic cell, catalyzes the formation and cleavage of disulfide bonds and thereby helps in protein folding. A decrease in PDI activity under ER stress conditions leads to protein misfolding, which is responsible for the progression of various human diseases, such as Alzheimer's, Parkinson's, diabetes mellitus, and atherosclerosis. Here we report that water-soluble cyclic diselenides mimic the multifunctional activity of the PDI family by facilitating oxidative folding, disulfide formation/reduction, and repair of the scrambled disulfide bonds in misfolded proteins.
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Affiliation(s)
- Kenta Arai
- Department of Chemistry, School of Science, Tokai University, Kitakaname, Hiratsuka-shi, Kanagawa, 259-1292, Japan
| | - Haruhito Ueno
- Department of Chemistry, School of Science, Tokai University, Kitakaname, Hiratsuka-shi, Kanagawa, 259-1292, Japan
| | - Yuki Asano
- Department of Chemistry, School of Science, Tokai University, Kitakaname, Hiratsuka-shi, Kanagawa, 259-1292, Japan
| | - Gaurango Chakrabarty
- Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore, 560012, India
| | - Shingo Shimodaira
- Department of Chemistry, School of Science, Tokai University, Kitakaname, Hiratsuka-shi, Kanagawa, 259-1292, Japan
| | - Govindasamy Mugesh
- Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore, 560012, India
| | - Michio Iwaoka
- Department of Chemistry, School of Science, Tokai University, Kitakaname, Hiratsuka-shi, Kanagawa, 259-1292, Japan
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Riaz O, Aqil A, Sisodia G, Chakrabarty G. P.F.C Sigma ® cruciate retaining fixed-bearing versus mobile-bearing knee arthroplasty: a prospective comparative study with minimum 10-year follow-up. Eur J Orthop Surg Traumatol 2017; 27:1145-1149. [PMID: 28210821 DOI: 10.1007/s00590-017-1920-1] [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] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Accepted: 01/26/2017] [Indexed: 10/20/2022]
Abstract
AIMS To prospectively compare long-term clinical and radiological outcomes following a cruciate retaining fixed-bearing (FB) and a mobile-bearing (MB) primary total knee replacement (TKR). METHODS We prospectively reviewed 113 TKRs in 99 patients (14 bilateral) with a PFC sigma cruciate retaining rotating platform system, at an average follow-up of 11.1 years (range 10-12). Results were contrasted with those from 89 TKRs in 72 patients (17 bilateral) with a PFC sigma cruciate fixed-bearing prosthesis, at an average follow-up of 12.1 years (range 10-14.1). Outcomes collected included pre- and post-operative range of motion, Oxford Knee Scores, complications encountered, as well as radiographical assessments of polyethylene wear. RESULTS In the MB group, mean Oxford Knee Scores improved from 16 pre-operatively to 42 at final follow-up. The mean range of motion was 115° (75-130). In the FB group, mean Oxford Knee Scores improved from 16.2 pre-operatively to 42.5 at final follow-up. The mean range of motion was 111.2 (80-135) degrees at final follow-up. CONCLUSION We failed to elicit an objectively demonstrable clinical difference between the MB- and FB-implanted knees. Similarly, radiological benefits of the MB implants with regard to polyethylene wear were not evident at a minimum 10-year follow-up.
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Affiliation(s)
- O Riaz
- The West Riding Knee Unit, Huddersfield Royal Infirmary, Calderdale and Huddersfield Foundation NHS Trust, Huddersfield, HD3 3EA, UK.
| | - A Aqil
- The West Riding Knee Unit, Huddersfield Royal Infirmary, Calderdale and Huddersfield Foundation NHS Trust, Huddersfield, HD3 3EA, UK
| | - G Sisodia
- The West Riding Knee Unit, Huddersfield Royal Infirmary, Calderdale and Huddersfield Foundation NHS Trust, Huddersfield, HD3 3EA, UK
| | - G Chakrabarty
- The West Riding Knee Unit, Huddersfield Royal Infirmary, Calderdale and Huddersfield Foundation NHS Trust, Huddersfield, HD3 3EA, UK
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Bilkhu A, Sisodia G, Chakrabarty G, Muralikuttan KP. Intramedullary fixation of a femoral shaft fracture with preservation of an existing hip resurfacing prosthesis. Injury 2015; 46:763-6. [PMID: 25636533 DOI: 10.1016/j.injury.2015.01.015] [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] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Accepted: 01/10/2015] [Indexed: 02/02/2023]
Abstract
Femoral neck fractures have been reported as a cause for failure in patients with a hip resurfacing arthroplasty. However, the incidence and management of fractures of the femoral shaft with an ipsilateral hip resurfacing arthroplasty is relatively absent in current literature. Although, the gold standard for the fixation of a closed femoral shaft fracture is with the use of an intramedullary nail, this can be a challenge in the presence of a hip resurfacing arthroplasty. We describe the case of anterograde intramedullary nail fixation for a femoral shaft fracture in a patient with an ipsilateral hip resurfacing arthroplasty in situ.
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Affiliation(s)
- A Bilkhu
- Department of Orthopaedics, Huddersfield Royal Infirmary, Acre Street, Huddersfield, West Yorkshire HD3 3EA, United Kingdom.
| | - G Sisodia
- Department of Orthopaedics, Huddersfield Royal Infirmary, Acre Street, Huddersfield, West Yorkshire HD3 3EA, United Kingdom.
| | - G Chakrabarty
- Department of Orthopaedics, Huddersfield Royal Infirmary, Acre Street, Huddersfield, West Yorkshire HD3 3EA, United Kingdom.
| | - K P Muralikuttan
- Department of Orthopaedics, Huddersfield Royal Infirmary, Acre Street, Huddersfield, West Yorkshire HD3 3EA, United Kingdom.
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Chakrabarty G, Groves C, Pollok R. Acute upper gastrointestinal bleeding: identifying low risk patients. Gut 2013; 62:184. [PMID: 22198712 DOI: 10.1136/gutjnl-2011-301682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/08/2022]
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Bhatt H, Rambani R, White W, Chakrabarty G. Primary total knee arthroplasty using the P.F.C Sigma®-rotating platform cruciate retaining endoprosthesis--a 6 year follow up. Knee 2012; 19:856-9. [PMID: 22595399 DOI: 10.1016/j.knee.2012.03.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [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: 10/17/2011] [Revised: 03/05/2012] [Accepted: 03/19/2012] [Indexed: 02/02/2023]
Abstract
BACKGROUND Mobile-bearing Total Knee Replacement allows unconstrained axial rotation. Increased articular conformity minimizes polyethylene contact stresses, thereby reducing linear wear and fatigue failure. METHODS We prospectively reviewed a consecutive series of 161 patients with mobile bearing total knee replacements using the PFC Sigma Cruciate Retaining Rotating Platform System. (DePuy, Leeds, United Kingdom) with midterm follow up (minimum 6 and maximum 9 years, mean 7.2 years). One hundred forty-seven patients from February 2001 to March 2004 were followed up till date. Primary osteoarthritis 96%; was the main indication followed by rheumatoid arthritis 3% and one case of psoriatic arthritis. Fifty-seven percent were females with mean age of 69.5 years (Range 51-90 years). Oxford and American Knee Society scores were measured. RESULTS Mean Oxford score improved from 43 (Range 29-55) pre operatively to 21(Range 13-44) at last follow up and mean Knee Society score from 53 (Range 43-70) to 80 (Range 58-90). Range of movement improved from 91° (Range 70-110) to 113° (Range 75-130) at last follow up. One patient had dislocation of bearing needing manipulation. One patient had superficial infection treated with antibiotics. No patients had deep infection. There was one case reported of deep vein thrombosis and one of non-fatal pulmonary embolism. CONCLUSION The midterm results in our series with PFC Sigma mobile bearing knee replacement are excellent with good outcome scores. Cohort will be followed for long term results. Level of Evidence IV.
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Affiliation(s)
- H Bhatt
- The West Riding Knee Unit, Huddersfield Royal Infirmary, Calderdale & Huddersfield Foundation NHS Trust, Huddersfield HD3 3EA, United Kingdom.
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Davies J, Pilling R, Dimri R, Chakrabarty G. Expert practical operative skills teaching in Trauma and Orthopaedics at a nominal cost. Surgeon 2012; 10:330-3. [PMID: 23141467 DOI: 10.1016/j.surge.2011.08.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2010] [Revised: 06/19/2011] [Accepted: 08/08/2011] [Indexed: 10/17/2022]
Abstract
BACKGROUND AND PURPOSE The AO Foundation Operative Fracture Management course is the gold standard in training courses currently available for trainees at ST3 level. We have devised a low cost operative skills course comprising instructional lectures, demonstrations and practical dry bone workshops. To assess the quality of teaching, candidates' feedback was analysed in two cohorts for the running of the course over two consecutive years: 2008 and 2009. METHODS Trainees were given short instructional lectures by consultant surgeons followed by workshops, with a trainer to candidate ratio of 1:4. A trauma inventory was provided by Stryker Trauma UK, ensuring a nominal fee for each candidate (£50). Feedback was anonymously collected according to a Likert scale and analysed using non-parametric methods appropriate for ranked data. MAIN FINDINGS Twenty one of 22 (95%) candidates gave feedback in 2008 and 18 out of 18 candidates (100%) in 2009. The teaching provided was highly rated consistently for both years, apart from an informal session on theatre tips and tricks in 2008. This was not repeated in 2009 to allow more practical time. Only one session, an intramedullary nailing lecture, had a significant difference in scores between the 2 years (p = 0.044) because of improved scores in 2009. CONCLUSIONS Due to changes in training, trainees have reduced exposure in theatre and this has implications for the early stages of acquiring practical operative skills. As an adjunct to the AO course, practical skills teaching by consultants in the format of a low cost skills workshop outside of a theatre environment can be achieved with support from a trauma implant supplier.
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Affiliation(s)
- J Davies
- Dept. of Trauma and Orthopaedics, Calderdale and Huddersfield NHS Trust, Huddersfield, UK.
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Blunt LA, Bills PJ, Jiang XQ, Chakrabarty G. Improvement in the assessment of wear of total knee replacements using coordinate-measuring machine techniques. Proc Inst Mech Eng H 2008; 222:309-18. [DOI: 10.1243/09544119jeim289] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Total joint replacement is one of the most common elective surgical procedures performed worldwide, with an estimate of 1.5×106 operations performed annually. Currently joint replacements are expected to function for 10–15 years; however, with an increase in life expectancy, and a greater call for knee replacement due to increased activity levels, there is a requirement to improve their function to offer longer-term improved quality of life for patients. Wear analysis of total joint replacements has long been an important means in determining failure mechanisms and improving longevity of these devices. The effectiveness of the coordinate-measuring machine (CMM) technique for assessing volumetric material loss during simulated life testing of a replacement knee joint has been proved previously by the present authors. The purpose of the current work is to present an improvement to this method for situations where no pre-wear data are available. To validate the method, simulator tests were run and gravimetric measurements taken throughout the test, such that the components measured had a known wear value. The implications of the results are then discussed in terms of assessment of joint functionality and development of standardized CMM-based product standards. The method was then expanded to allow assessment of clinically retrieved bearings so as to ascertain a measure of true clinical wear.
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Affiliation(s)
- L A Blunt
- Centre for Precision Technologies, School of Computing & Engineering, The University of Huddersfield, Huddersfield, UK
| | - P J Bills
- Centre for Precision Technologies, School of Computing & Engineering, The University of Huddersfield, Huddersfield, UK
| | - X-Q Jiang
- Centre for Precision Technologies, School of Computing & Engineering, The University of Huddersfield, Huddersfield, UK
| | - G Chakrabarty
- West Riding Knee nit, Huddersfield Royal Infirmary, Huddersfield, UK
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Abstract
We present a case of chondromalacia of the fabella, describe a provocative diagnostic test and review the literature on this unusual cause of knee pain.
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Affiliation(s)
- A Robertson
- Huddersfield Royal Infirmary, Acre Street, Lindley, Huddersfield, HD3 3EA, UK.
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Adams MA, Kerin AJ, Bhatia LS, Chakrabarty G, Dolan P. Experimental determination of stress distributions in articular cartilage before and after sustained loading. Clin Biomech (Bristol, Avon) 1999; 14:88-96. [PMID: 10619095 DOI: 10.1016/s0268-0033(98)00060-6] [Citation(s) in RCA: 15] [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] [Indexed: 02/07/2023]
Abstract
OBJECTIVE To test the hypotheses that stress concentrations exist within articular cartilage, and are intensified by sustained 'creep' loading. DESIGN Matched-pair comparison of stress distributions in cartilage, in vitro, before and after creep. BACKGROUND The ability of cartilage to equalize contact stresses between articulating surfaces may be compromised by undulations in the subchondral bone, and by variations in chemical composition. Furthermore, any stress concentrations within cartilage may be affected by creep loading, which-reduces its water content. METHODS Sixteen specimens of apparently normal cartilage-on-bone, 12 mm x 15 mm, were removed from the femoral condyles and tibial plateaux of patients undergoing total knee replacement. The cartilage was subjected to a nominal compressive stress of 2 MPa by means of a 10 mm-diameter flat impermeable indentor. During the 20 s loading period, a miniature pressure transducer, side-mounted in a 0.9 mm-diameter needle, was pulled through the cartilage in a direction parallel to the surface, while transducer output and position were sampled at 25 Hz. 'Stress profiles' were obtained with the transducer pointing in the 12 o'clock and 3 o'clock directions, and were repeated after creep loading at 1.6 MPa for 2 h. RESULTS Validation tests indicated that transducer output was proportional to the average compressive stress, but overestimated it by 9-15%. Stresses were greatest under the centre of the indentor, and showed local variations ('concentrations') which were increased in number and size after creep loading. CONCLUSIONS Measured values of compressive stress incorporate small systematic errors. Nevertheless, the results presented clearly support both hypotheses.
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Affiliation(s)
- M A Adams
- Department of Anatomy, University of Bristol, UK.
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Abstract
In 73 unicompartmental arthroplasties of the knee that were revised, the major causes of failure were progression of arthritis and implant failure. The interval between the primary and revision averaged 56 months. Eighty-eight percent were revised to a variety of total condylar prostheses. Bone loss was classified by defect at the end of preparation. In 31 patients, there were none; in 17, the defect was in either the femur or the tibia; and in 25, there were defects in both the femur and the tibia. Forty-seven of these defects were small and contained, presenting little problem. Twenty defects were either large, contained, or peripheral, requiring reconstruction. Fifteen knees were lost as a result of death (but there had been satisfactory knee function); 2 were lost to follow-up evaluation, and 3 have required further revision. Seventy-nine percent of the surviving knees had excellent or good knee function at an average follow-up period of 56 months.
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