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Thomas A, Bentley L, Feeney C, Lofts S, Robb C, Rowe EC, Thomson A, Warren-Thomas E, Emmett B. Land degradation neutrality: Testing the indicator in a temperate agricultural landscape. J Environ Manage 2023; 346:118884. [PMID: 37729834 DOI: 10.1016/j.jenvman.2023.118884] [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] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 08/22/2023] [Accepted: 08/26/2023] [Indexed: 09/22/2023]
Abstract
Land degradation directly affects around 25% of land globally, undermining progress on most of the UN Sustainable Development Goals (SDG), particularly target 15.3. To assess land degradation, SDG indicator 15.3.1 combines sub-indicators of productivity, soil carbon and land cover. Over 100 countries have set Land Degradation Neutrality (LDN) targets. Here, we demonstrate application of the indicator for a well-established agricultural landscape using the case study of Great Britain. We explore detection of degradation in such landscapes by: 1) transparently evaluating land cover transitions; 2) comparing assessments using global and national data; 3) identifying misleading trends; and 4) including extra sub-indicators for additional forms of degradation. Our results demonstrate significant impacts on the indicator both from the land cover transition evaluation and choice or availability of data. Critically, we identify a misleading improvement trend due to a trade-off between improvement detected by the productivity sub-indicator, and 30-year soil carbon loss trends in croplands (11% from 1978 to 2007). This carbon loss trend would not be identified without additional data from Countryside Survey (CS). Thus, without incorporating field survey data we risk overlooking the degradation of regulating and supporting ecosystem services (linked to soil carbon), in favour of signals from improving provisioning services (productivity sub-indicator). Relative importance of these services will vary between socioeconomic contexts. Including extra sub-indicators for erosion or critical load exceedance, as additional forms of degradation, produced a switch from net area improving (9%) to net area degraded (58%). CS data also identified additional degradation for soil health, including 44% arable soils exceeding bulk density thresholds and 35% of CS squares exceeding contamination thresholds for metals.
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Affiliation(s)
- Amy Thomas
- UK Centre for Ecology & Hydrology, Environment Centre Wales, Deiniol Road, Bangor, LL57 2UW, UK.
| | - Laura Bentley
- UK Centre for Ecology & Hydrology, Environment Centre Wales, Deiniol Road, Bangor, LL57 2UW, UK
| | - Chris Feeney
- UK Centre for Ecology & Hydrology, Environment Centre Wales, Deiniol Road, Bangor, LL57 2UW, UK
| | - Stephen Lofts
- UK Centre for Ecology & Hydrology, Library Avenue, Bailrigg, Lancaster, LA1 4AP, UK
| | - Ciaran Robb
- UK Centre for Ecology & Hydrology, Environment Centre Wales, Deiniol Road, Bangor, LL57 2UW, UK
| | - Ed C Rowe
- UK Centre for Ecology & Hydrology, Environment Centre Wales, Deiniol Road, Bangor, LL57 2UW, UK
| | - Amanda Thomson
- UK Centre for Ecology & Hydrology, Bush Estate, Penicuik, EH26 0QB, UK
| | - Eleanor Warren-Thomas
- UK Centre for Ecology & Hydrology, Environment Centre Wales, Deiniol Road, Bangor, LL57 2UW, UK
| | - Bridget Emmett
- UK Centre for Ecology & Hydrology, Environment Centre Wales, Deiniol Road, Bangor, LL57 2UW, UK
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Feeney CJ, Robinson DA, Keith AM, Vigier A, Bentley L, Smith RP, Garbutt A, Maskell LC, Norton L, Wood CM, Cosby BJ, Emmett BA. Development of soil health benchmarks for managed and semi-natural landscapes. Sci Total Environ 2023; 886:163973. [PMID: 37164075 DOI: 10.1016/j.scitotenv.2023.163973] [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] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 04/28/2023] [Accepted: 05/02/2023] [Indexed: 05/12/2023]
Abstract
Efforts to improve soil health require that target values of key soil properties are established. No agreed targets exist but providing population data as benchmarks is a useful step to standardise soil health comparison between landscapes. We exploited nationally representative topsoil (0-15 cm) measurements to derive soil health benchmarks for managed and semi-natural environments across Great Britain. In total, 4587 soil organic matter (SOM), 3860 pH, 2908 bulk density (BD), and 465 earthworm abundance (EA) datapoints were used. As soil properties are sensitive to site-specific characteristics, data were stratified by habitat, soil type, and mean annual precipitation, with benchmarks defined as the middle 80 % of values in each distribution - yielding 135 benchmarks. BD and pH decreased with land management intensity (agriculture > semi-natural grasslands > woodlands > heathlands > wetlands), and vice versa for SOM and EA. Normalising benchmark ranges by medians revealed soil health indicator benchmark widths increased in the order: pH < BD < SOM < EA, while width increased with decreasing land management intensity. Arable and horticulture and improved grassland exhibited narrow benchmarks for SOM, pH and BD, yet the widest EA benchmark, suggesting additional drivers impact EA patterns. Upland wetlands had the widest BD benchmarks, important when determining carbon stocks. East Anglia currently possesses the largest proportions of atypical soils, including below typical SOM (19.2 %), above typical BD (17.4 %) and pH (39.1 %), and the smallest proportions of above typical SOM (2.4 %), and below typical BD (5.8 %) and pH (2.3 %). This is found even after land use, soil type and rainfall have been considered, underscoring how urgently soil health should be addressed here. Our benchmarking framework allows landowners to compare where their measured soil health indicators fall within expected ranges and is applicable to other biomes, national and multinational contexts.
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Affiliation(s)
- Christopher J Feeney
- UK Centre for Ecology and Hydrology, Environment Centre Wales, Deiniol Road, Bangor, Gwynedd LL57 2UW, UK.
| | - David A Robinson
- UK Centre for Ecology and Hydrology, Environment Centre Wales, Deiniol Road, Bangor, Gwynedd LL57 2UW, UK
| | - Aidan M Keith
- UK Centre for Ecology and Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster LA1 4AP, UK
| | - Audric Vigier
- UK Centre for Ecology and Hydrology, Bush Estate, Penicuik, Midlothian EH26 OQB, UK
| | - Laura Bentley
- UK Centre for Ecology and Hydrology, Environment Centre Wales, Deiniol Road, Bangor, Gwynedd LL57 2UW, UK
| | - Richard P Smith
- Environment Agency, Manley House, Kestrel Way, Exeter EX2 7LQ, UK
| | - Angus Garbutt
- UK Centre for Ecology and Hydrology, Environment Centre Wales, Deiniol Road, Bangor, Gwynedd LL57 2UW, UK
| | - Lindsay C Maskell
- UK Centre for Ecology and Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster LA1 4AP, UK
| | - Lisa Norton
- UK Centre for Ecology and Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster LA1 4AP, UK
| | - Claire M Wood
- UK Centre for Ecology and Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster LA1 4AP, UK
| | - B Jack Cosby
- UK Centre for Ecology and Hydrology, Environment Centre Wales, Deiniol Road, Bangor, Gwynedd LL57 2UW, UK
| | - Bridget A Emmett
- UK Centre for Ecology and Hydrology, Environment Centre Wales, Deiniol Road, Bangor, Gwynedd LL57 2UW, UK
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Robinson DA, Nemes A, Reinsch S, Radbourne A, Bentley L, Keith AM. Global meta-analysis of soil hydraulic properties on the same soils with differing land use. Sci Total Environ 2022; 852:158506. [PMID: 36058328 DOI: 10.1016/j.scitotenv.2022.158506] [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] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 08/30/2022] [Accepted: 08/30/2022] [Indexed: 06/15/2023]
Abstract
Global land use change has resulted in more pasture and cropland, largely at the expense of woodlands, over the last 300 years. How this change affects soil hydraulic function with regard to feedbacks to the hydrological cycle is unclear for earth system modelling (ESM). Pedotransfer functions (PTFs) used to predict soil hydraulic conductivity (K) take no account of land use. Here, we synthesize >800 measurements from around the globe from sites that measured near-saturated soil hydraulic conductivity, or infiltration, at the soil surface, on the same soil type at each location, but with differing land use, woodland (W), grassland (G) and cropland (C). We found that texture based PTFs predict K reasonably well for cropland giving unbiased results, but increasingly underestimate K in grassland and woodland. In native woodland and grassland differences in K can usually be accounted for by differences in bulk density. However, heavy grazing K responses can be much lower indicating compaction likely reduces connectivity. We show that the K response ratios (RR) between land uses vary with cropland (C/W = 0.45 [W/C = 2.2]) and grassland (G/W = 0.63 [W/G = 1.6]) having about half the K of woodland.
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Affiliation(s)
- David A Robinson
- UK Centre for Ecology & Hydrology, Environment Centre Wales, Bangor, United Kingdom.
| | - Attila Nemes
- Division of Environment and Natural Resources, Norwegian Institute of Bioeconomy Research, Ås, Norway; Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, Ås, Norway
| | - Sabine Reinsch
- UK Centre for Ecology & Hydrology, Environment Centre Wales, Bangor, United Kingdom
| | - Alan Radbourne
- UK Centre for Ecology & Hydrology, Environment Centre Wales, Bangor, United Kingdom
| | - Laura Bentley
- UK Centre for Ecology & Hydrology, Environment Centre Wales, Bangor, United Kingdom
| | - Aidan M Keith
- UK Centre for Ecology & Hydrology, Library Avenue, Bailrigg, Lancaster, United Kingdom
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Leong C, Teoh T, Bentley L, O'Rourke E, Lim W, Htun N, Premaratne M. Downstream Impact Of Expansion Of Computed Tomography Coronary Angiography: An Australian Single Tertiary Center Experience. J Cardiovasc Comput Tomogr 2020. [DOI: 10.1016/j.jcct.2020.06.027] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Rischin A, Kathpal E, Vogrin S, Bentley L, Master V, Steward A, Le Marshall K, Lim K. AB1126 THE RELIABILITY AND DIAGNOSTIC ACCURACY OF DIGITAL TOMOSYNTHESIS COMPARED WITH CONVENTIONAL RADIOGRAPHY FOR THE INVESTIGATION OF SACROILIITIS. Ann Rheum Dis 2020. [DOI: 10.1136/annrheumdis-2020-eular.3521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Background:Conventional radiography remains part of the diagnosis of axial spondyloarthritis and determines qualification for biologic disease modifying anti-rheumatic drugs in many countries. The standard anteroposterior radiograph (XR) incompletely images the complex sacroiliac joint with recognised unacceptably low levels of agreement between readers. Digital tomosynthesis (DTS) uses conventional radiographic projections to create a three-dimensional image and is a potential alternative for the initial radiographic detection and grading of sacroiliitis.Objectives:To compare the level of agreement between two radiologists when reporting sacroiliac joint imaging with digital tomosynthesis versus conventional radiography, as well as to compare the diagnostic accuracy of each imaging modality.Methods:229 consecutive patients that had radiography and digital tomosynthesis performed at Footscray Hospital, Melbourne, Australia were included. Two blinded radiologists independently re-reported all images according to the modified New York criteria, or listed an alternative diagnosis. An overall assessment of each image as inflammatory sacroiliitis, normal or non-inflammatory disease was also recorded. Demographic and clinical data were extracted from medical records. Agreement between and within readers was evaluated using kappa (κ) statistic. Diagnostic accuracy was calculated by comparing each reader’s overall assessment against 2 reference standard comparators: most recent rheumatologist diagnosis and fulfillment of ASAS criteria at any time point.Results:The intra-reader agreement of reader 1 was almost perfect for the left, right and overall sacroiliac joint assessments (κ 0.77 - 0.94), with DTS outperforming XR. Reader 2 agreement was mostly moderate (κ 0.39 - 0.69), with DTS and XR better on the left and right sacroiliac joint respectively, but XR having better overall assessment. The inter-reader agreement of DTS for all patients was moderate and better than XR as shown in the Table. When excluding non-spondyloarthritis patients, inter-reader agreement improved (κ 0.50 to 0.58) but there was no significant difference between DTS and XR. Using reader 1, the sensitivity of DTS (64.8 - 66.7%) was better than XR (54.9 - 60.7%) but low, in keeping with what is known about radiographic sacroiliitis and axial spondyloarthritis. The specificity of XR (78.5 – 80.3%) was better than DTS (72.3 – 73.1%). There were no significant differences when fulfillment of modified New York Criteria was used as a reader’s positive test.Table.Inter-rater reliability between the readersAll patients(N=229)*Inflammatory sacroiliitis & normal patients (N=164)**Inflammatory sacroiliitis patients (N=92)**XR Right0.360.520.56DTS Right0.390.500.51XR Left0.340.550.56DTS Left0.420.550.58XR Overall0.40DTS Overall0.45*Non-weighted kappa statistic**Weighted kappa statisticConclusion:DTS demonstrated moderate reliability for assessment of sacroiliitis, marginally better than conventional radiography. Overall levels of agreement for both imaging modalities were however lower than radiography in previous studies, with several possible contributing factors. A prospective study in a selected spondyloarthritis cohort may better determine any benefit of DTS.References:[1]Christiansen AA, Hendricks O, Kuettel D, Horslev-Petersen K, Jurik AG, Nielsen S, et al. Limited Reliability of Radiographic Assessment of Sacroiliac Joints in Patients with Suspected Early Spondyloarthritis. The Journal of rheumatology. 2017;44(1):70-7.[2]van Tubergen A, Heuft-Dorenbosch L, Schulpen G, Landewe R, Wijers R, van der Heijde D, et al. Radiographic assessment of sacroiliitis by radiologists and rheumatologists: does training improve quality? Annals of the rheumatic diseases. 2003;62(6):519-25.Disclosure of Interests:None declared
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Bentley L, Coomes DA. Partial river flow recovery with forest age is rare in the decades following establishment. Glob Chang Biol 2020; 26:1458-1473. [PMID: 31955488 PMCID: PMC7079061 DOI: 10.1111/gcb.14954] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 11/13/2019] [Indexed: 05/24/2023]
Abstract
Forest regeneration and expansion are occurring in many countries, with 80 million ha established from 2000 to 2012 under the Bonn accord and 17.5 million ha established from 1990 to 2005 according to the Food and Agriculture Organisation. Multiple reviews have linked increasing forest cover with reduced river flow and potentially detrimental effects downstream. Previous reviews have investigated trends in river flow response over time, but the influence of forest age remains uncertain. Partial river flow recovery (towards non-forested conditions) has been reported in decades following forest establishment, but the role of climate in driving these trends has not been explored. Here, we evaluate river flow trends in 43 studies following forest establishment, which provide sufficient information to distinguish the effects of ageing forests from variable climate. Our meta-analysis supports previous findings showing that forestation reduces annual river flow (by 23% after 5 years and 38% after 25 years) with greater reductions in catchments with higher mean annual precipitation, larger increases in forest cover, and which were idle, rather than agricultural land, prior to forestation. The impact of forests on river flow is sensitive to annual precipitation and potential evapotranspiration, but responses are highly variable. Forests affect river flow less when annual precipitation is low, and sensitivity to precipitation decreases as catchment aridity increases. The majority of catchments demonstrated persistent river flow declines after forest establishment. However, nine catchments showed partial flow recovery after an initial decrease, with peak flow reductions at an average age of 15 and across a range of tree species. The mean rate of recovery was 34 mm/year over 5 years. Partial flow recovery with forest age cannot be commonly expected, however, and forestation programmes should take into account that changes to annual river flow are likely to persist for up to five decades.
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Affiliation(s)
- Laura Bentley
- Department of Plant Sciences in the Conservation Research InstituteUniversity of CambridgeCambridgeUK
| | - David A. Coomes
- Department of Plant Sciences in the Conservation Research InstituteUniversity of CambridgeCambridgeUK
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Xi L, De Falco P, Barbieri E, Karunaratne A, Bentley L, Esapa CT, Davis GR, Terrill NJ, Cox RD, Pugno NM, Thakker RV, Weinkamer R, Wu WW, Fang DN, Gupta HS. Reduction of fibrillar strain-rate sensitivity in steroid-induced osteoporosis linked to changes in mineralized fibrillar nanostructure. Bone 2020; 131:115111. [PMID: 31726107 DOI: 10.1016/j.bone.2019.115111] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 10/13/2019] [Accepted: 10/15/2019] [Indexed: 01/29/2023]
Abstract
As bone is used in a dynamic mechanical environment, understanding the structural origins of its time-dependent mechanical behaviour - and the alterations in metabolic bone disease - is of interest. However, at the scale of the mineralized fibrillar matrix (nanometre-level), the nature of the strain-rate dependent mechanics is incompletely understood. Here, we investigate the fibrillar- and mineral-deformation behaviour in a murine model of Cushing's syndrome, used to understand steroid induced osteoporosis, using synchrotron small- and wide-angle scattering/diffraction combined with in situ tensile testing at three strain rates ranging from 10-4 to 10-1 s-1. We find that the effective fibril- and mineral-modulus and fibrillar-reorientation show no significant increase with strain-rate in osteoporotic bone, but increase significantly in normal (wild-type) bone. By applying a fibril-lamellar two-level structural model of bone matrix deformation to fit the results, we obtain indications that altered collagen-mineral interactions at the nanoscale - along with altered fibrillar orientation distributions - may be the underlying reason for this altered strain-rate sensitivity. Our results suggest that an altered strain-rate sensitivity of the bone matrix in osteoporosis may be one of the contributing factors to reduced mechanical competence in such metabolic bone disorders, and that increasing this sensitivity may improve biomechanical performance.
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Affiliation(s)
- L Xi
- Institute of Advanced Structure Technology, Beijing Institute of Technology, Beijing 100081, China; School of Engineering and Material Sciences, Queen Mary University of London, London, E1 4NS, UK.
| | - P De Falco
- School of Engineering and Material Sciences, Queen Mary University of London, London, E1 4NS, UK; Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, D-14424 Potsdam-Golm, Germany.
| | - E Barbieri
- School of Engineering and Material Sciences, Queen Mary University of London, London, E1 4NS, UK; Department of Mathematical Science and Advanced Technology (MAT), Yokohama Institute for Earth Sciences (YES) 3173-25, Showa-machi, Kanazawa-ku, Yokohama-city, Japan.
| | - A Karunaratne
- Department of Mechanical Engineering, University of Moratuwa, Sri Lanka.
| | - L Bentley
- MRC Mammalian Genetics Unit and Mary Lyon Centre, MRC Harwell, Harwell Science and Innovation Campus, OX11 0RD, UK.
| | - C T Esapa
- MRC Mammalian Genetics Unit and Mary Lyon Centre, MRC Harwell, Harwell Science and Innovation Campus, OX11 0RD, UK; Academic Endocrine Unit, Radcliffe Department of Clinical Medicine, Oxford Centre for Diabetes, Endocrinology and Metabolism (OCDEM), University of Oxford, Churchill Hospital, Headington, Oxford, OX3 7JL, UK.
| | - G R Davis
- Dental Physical Sciences Unit, Queen Mary University of London, London, E1 4NS, UK.
| | - N J Terrill
- Beamline I22, Diamond Light Source Ltd., Diamond House, Harwell Science and Innovation Campus, Chilton, Didcot, Oxfordshire, OX11 0DE, United Kingdom
| | - R D Cox
- MRC Mammalian Genetics Unit and Mary Lyon Centre, MRC Harwell, Harwell Science and Innovation Campus, OX11 0RD, UK.
| | - N M Pugno
- Laboratory of Bio-Inspired & Graphene Nanomechanics, Department of Civil, Environmental and Mechanical Engineering, University of Trento, Via Mesiano, 77, 38123, Trento, Italy; School of Engineering and Material Sciences, Queen Mary University of London, London, E1 4NS, UK; Ket Lab, Edoardo Amaldi Foundation, Via del Politecnico snc, 00133, Rome, Italy.
| | - R V Thakker
- Academic Endocrine Unit, Radcliffe Department of Clinical Medicine, Oxford Centre for Diabetes, Endocrinology and Metabolism (OCDEM), University of Oxford, Churchill Hospital, Headington, Oxford, OX3 7JL, UK.
| | - R Weinkamer
- Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, D-14424 Potsdam-Golm, Germany.
| | - W W Wu
- Institute of Advanced Structure Technology, Beijing Institute of Technology, Beijing 100081, China.
| | - D N Fang
- Institute of Advanced Structure Technology, Beijing Institute of Technology, Beijing 100081, China; State Key Laboratory for Turbulence and Complex Systems, College of Engineering, Peking University, Beijing, China.
| | - H S Gupta
- School of Engineering and Material Sciences, Queen Mary University of London, London, E1 4NS, UK.
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Bentley L, Barr B. Poverty and income support among older people with disabilities and out of work in the UK and Canada. Eur J Public Health 2018. [DOI: 10.1093/eurpub/cky212.817] [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: 11/12/2022] Open
Affiliation(s)
- L Bentley
- University of Liverpool, Liverpool, UK
| | - B Barr
- University of Liverpool, Liverpool, UK
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Xi L, De Falco P, Barbieri E, Karunaratne A, Bentley L, Esapa CT, Terrill NJ, Brown SDM, Cox RD, Davis GR, Pugno NM, Thakker RV, Gupta HS. Bone matrix development in steroid-induced osteoporosis is associated with a consistently reduced fibrillar stiffness linked to altered bone mineral quality. Acta Biomater 2018; 76:295-307. [PMID: 29902593 PMCID: PMC6084282 DOI: 10.1016/j.actbio.2018.05.053] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Revised: 05/14/2018] [Accepted: 05/31/2018] [Indexed: 01/24/2023]
Abstract
Glucocorticoid-induced osteoporosis (GIOP) is a major secondary form of osteoporosis, with the fracture risk significantly elevated - at similar levels of bone mineral density - in patients taking glucocorticoids compared with non-users. The adverse bone structural changes at multiple hierarchical levels in GIOP, and their mechanistic consequences leading to reduced load-bearing capacity, are not clearly understood. Here we combine experimental X-ray nanoscale mechanical imaging with analytical modelling of the bone matrix mechanics to determine mechanisms causing bone material quality deterioration during development of GIOP. In situ synchrotron small-angle X-ray diffraction combined with tensile testing was used to measure nanoscale deformation mechanisms in a murine model of GIOP, due to a corticotrophin-releasing hormone promoter mutation, at multiple ages (8-, 12-, 24- and 36 weeks), complemented by quantitative micro-computed tomography and backscattered electron imaging to determine mineral concentrations. We develop a two-level hierarchical model of the bone matrix (mineralized fibril and lamella) to predict fibrillar mechanical response as a function of architectural parameters of the mineralized matrix. The fibrillar elastic modulus of GIOP-bone is lower than healthy bone throughout development, and nearly constant in time, in contrast to the progressively increasing stiffness in healthy bone. The lower mineral platelet aspect ratio value for GIOP compared to healthy bone in the multiscale model can explain the fibrillar deformation. Consistent with this result, independent measurement of mineral platelet lengths from wide-angle X-ray diffraction finds a shorter mineral platelet length in GIOP. Our results show how lowered mineralization combined with altered mineral nanostructure in GIOP leads to lowered mechanical competence. SIGNIFICANCE STATEMENT Increased fragility in musculoskeletal disorders like osteoporosis are believed to arise due to alterations in bone structure at multiple length-scales from the organ down to the supramolecular-level, where collagen molecules and elongated mineral nanoparticles form stiff fibrils. However, the nature of these molecular-level alterations are not known. Here we used X-ray scattering to determine both how bone fibrils deform in secondary osteoporosis, as well as how the fibril orientation and mineral nanoparticle structure changes. We found that osteoporotic fibrils become less stiff both because the mineral nanoparticles became shorter and less efficient at transferring load from collagen, and because the fibrils are more randomly oriented. These results will help in the design of new composite musculoskeletal implants for bone repair.
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Affiliation(s)
- L Xi
- School of Engineering and Material Sciences, Queen Mary University of London, London E1 4NS, UK; Department of Nuclear Engineering, North Carolina State University, Raleigh, NC 27607, USA
| | - P De Falco
- School of Engineering and Material Sciences, Queen Mary University of London, London E1 4NS, UK; Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, D-14424 Potsdam-Golm, Germany.
| | - E Barbieri
- School of Engineering and Material Sciences, Queen Mary University of London, London E1 4NS, UK; Department of Mathematical Science and Advanced Technology (MAT), Yokohama Institute for Earth Sciences (YES) 3173-25, Showa-machi, Kanazawa-ku, Yokohama-city, Japan.
| | - A Karunaratne
- Department of Mechanical Engineering, University of Moratuwa, Sri Lanka
| | - L Bentley
- MRC Mammalian Genetics Unit and Mary Lyon Centre, MRC Harwell, Harwell Science and Innovation Campus, OX11 0RD, UK.
| | - C T Esapa
- MRC Mammalian Genetics Unit and Mary Lyon Centre, MRC Harwell, Harwell Science and Innovation Campus, OX11 0RD, UK; Academic Endocrine Unit, Nuffield Department of Clinical Medicine, Oxford Centre for Diabetes, Endocrinology and Metabolism (OCDEM), University of Oxford, Churchill Hospital, Headington, Oxford OX3 7JL, UK.
| | - N J Terrill
- Beamline I22, Diamond Light Source Ltd., Diamond House, Harwell Science and Innovation Campus, Chilton, Didcot, Oxfordshire OX11 0DE, UK.
| | - S D M Brown
- MRC Mammalian Genetics Unit and Mary Lyon Centre, MRC Harwell, Harwell Science and Innovation Campus, OX11 0RD, UK.
| | - R D Cox
- MRC Mammalian Genetics Unit and Mary Lyon Centre, MRC Harwell, Harwell Science and Innovation Campus, OX11 0RD, UK.
| | - G R Davis
- Queen Mary University of London, Barts and the London School of Medicine and Dentistry, Institute of Dentistry, E1 2AD, UK.
| | - N M Pugno
- Laboratory of Bio-Inspired & Graphene Nanomechanics, Department of Civil, Environmental and Mechanical Engineering, University of Trento, Via Mesiano, 77, 38123 Trento, Italy; School of Engineering and Material Sciences, Queen Mary University of London, London E1 4NS, UK; Ket Lab, Edoardo Amaldi Foundation, Italian Space Agency, Via del Politecnico snc, 00133 Rome, Italy.
| | - R V Thakker
- MRC Mammalian Genetics Unit and Mary Lyon Centre, MRC Harwell, Harwell Science and Innovation Campus, OX11 0RD, UK; Academic Endocrine Unit, Nuffield Department of Clinical Medicine, Oxford Centre for Diabetes, Endocrinology and Metabolism (OCDEM), University of Oxford, Churchill Hospital, Headington, Oxford OX3 7JL, UK.
| | - H S Gupta
- School of Engineering and Material Sciences, Queen Mary University of London, London E1 4NS, UK.
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McAllister A, Bentley L, Brønnum-Hansen H, Liao Q, Nylen LL, Mustard C, Burström B. Social differentials in older persons’ employment in Canada, Denmark, Sweden and the UK in 2010-15. Eur J Public Health 2017. [DOI: 10.1093/eurpub/ckx187.266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
| | - L Bentley
- University of Liverpool, Liverpool, UK
| | | | - Q Liao
- Institute for Work and Health, Toronto, Canada
| | - L L Nylen
- Karolinska Institutet, Stockholm, Sweden
| | - C Mustard
- Institute for Work and Health, Toronto, Canada
| | - B Burström
- Karolinska Institutet, Stockholm, Sweden
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Karunaratne A, Xi L, Bentley L, Sykes D, Boyde A, Esapa CT, Terrill NJ, Brown SDM, Cox RD, Thakker RV, Gupta HS. Multiscale alterations in bone matrix quality increased fragility in steroid induced osteoporosis. Bone 2016; 84:15-24. [PMID: 26657825 PMCID: PMC4764652 DOI: 10.1016/j.bone.2015.11.019] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Revised: 10/30/2015] [Accepted: 11/27/2015] [Indexed: 12/31/2022]
Abstract
A serious adverse clinical effect of glucocorticoid steroid treatment is secondary osteoporosis, enhancing fracture risk in bone. This rapid increase in bone fracture risk is largely independent of bone loss (quantity), and must therefore arise from degradation of the quality of the bone matrix at the micro- and nanoscale. However, we lack an understanding of both the specific alterations in bone quality n steroid-induced osteoporosis as well as the mechanistic effects of these changes. Here we demonstrate alterations in the nanostructural parameters of the mineralized fibrillar collagen matrix, which affect bone quality, and develop a model linking these to increased fracture risk in glucocorticoid induced osteoporosis. Using a mouse model with an N-ethyl-N-nitrosourea (ENU)-induced corticotrophin releasing hormone promoter mutation (Crh(-120/+)) that developed hypercorticosteronaemia and osteoporosis, we utilized in situ mechanical testing with small angle X-ray diffraction, synchrotron micro-computed tomography and quantitative backscattered electron imaging to link altered nano- and microscale deformation mechanisms in the bone matrix to abnormal macroscopic mechanics. We measure the deformation of the mineralized collagen fibrils, and the nano-mechanical parameters including effective fibril modulus and fibril to tissue strain ratio. A significant reduction (51%) of fibril modulus was found in Crh(-120/+) mice. We also find a much larger fibril strain/tissue strain ratio in Crh(-120/+) mice (~1.5) compared to the wild-type mice (~0.5), indicative of a lowered mechanical competence at the nanoscale. Synchrotron microCT show a disruption of intracortical architecture, possibly linked to osteocytic osteolysis. These findings provide a clear quantitative demonstration of how bone quality changes increase macroscopic fragility in secondary osteoporosis.
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Affiliation(s)
- A Karunaratne
- Queen Mary University of London, School of Engineering and Material Science, Mile End Road, London E1 4NS, UK.
| | - L Xi
- Queen Mary University of London, School of Engineering and Material Science, Mile End Road, London E1 4NS, UK.
| | - L Bentley
- MRC Mammalian Genetics Unit and Mary Lyon Centre, MRC Harwell, Harwell Science and Innovation Campus, OX11 0RD, UK.
| | - D Sykes
- Core Research Laboratories, The Natural History Museum, London SW7 5BD, UK.
| | - A Boyde
- Queen Mary University of London, Barts and the London School of Medicine and Dentistry, Institute of Dentistry, E1 2AD, UK.
| | - C T Esapa
- MRC Mammalian Genetics Unit and Mary Lyon Centre, MRC Harwell, Harwell Science and Innovation Campus, OX11 0RD, UK; Academic Endocrine Unit, Nuffield Department of Clinical Medicine, Oxford Centre for Diabetes, Endocrinology and Metabolism (OCDEM), University of Oxford, Churchill Hospital, Headington, Oxford OX3 7JL, UK.
| | - N J Terrill
- Diamond Light Source Ltd., Beamline I22, Diamond House, Harwell Science and Innovation Campus, Chilton, Didcot, Oxfordshire, OX11 0DE, UK; Department of Chemistry, University of Sheffield, Dainton Building, Brookhill, Sheffield S3 7HF, UK.
| | - S D M Brown
- MRC Mammalian Genetics Unit and Mary Lyon Centre, MRC Harwell, Harwell Science and Innovation Campus, OX11 0RD, UK.
| | - R D Cox
- MRC Mammalian Genetics Unit and Mary Lyon Centre, MRC Harwell, Harwell Science and Innovation Campus, OX11 0RD, UK.
| | - R V Thakker
- Academic Endocrine Unit, Nuffield Department of Clinical Medicine, Oxford Centre for Diabetes, Endocrinology and Metabolism (OCDEM), University of Oxford, Churchill Hospital, Headington, Oxford OX3 7JL, UK.
| | - H S Gupta
- Queen Mary University of London, School of Engineering and Material Science, Mile End Road, London E1 4NS, UK.
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12
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Palmier-Claus JE, Myin-Germeys I, Barkus E, Bentley L, Udachina A, Delespaul PAEG, Lewis SW, Dunn G. Experience sampling research in individuals with mental illness: reflections and guidance. Acta Psychiatr Scand 2011; 123:12-20. [PMID: 20712828 DOI: 10.1111/j.1600-0447.2010.01596.x] [Citation(s) in RCA: 171] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
OBJECTIVE The experience sampling method (ESM) represents a valuable way of assessing clinical phenomena in real world settings and across time. Despite its theoretical advantages, using this methodology in psychiatric populations is challenging. This paper acts as a guide to researchers wishing to employ this approach when investigating mental illness. METHOD The contents represent the opinions of researchers around the United Kingdom and the Netherlands who are experienced at using the ESM. RESULTS In ESM studies, participants are required to fill in questions about their current thoughts, feelings and experiences when prompted by an electronic device (e.g. a wristwatch, PDA). Entries are typically made at fixed or random intervals over 6 days. This article outlines how to design and validate an ESM diary. We then discuss which sampling procedure to use and how to increase compliance through effective briefing and telephone sessions. Debriefing, data management and analytical issues are considered, before suggestions for future clinical uses of the ESM are made. CONCLUSION The last decade has seen an increase in the number of studies employing the ESM in clinical research. Further research is needed to examine the optimal equipment and procedure for different clinical groups.
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13
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Pauws E, Hoshino A, Bentley L, Prajapati S, Keller C, Hammond P, Martinez-Barbera JP, Moore GE, Stanier P. Tbx22null mice have a submucous cleft palate due to reduced palatal bone formation and also display ankyloglossia and choanal atresia phenotypes. Hum Mol Genet 2010. [DOI: 10.1093/hmg/ddq223] [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] Open
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14
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Abstract
OBJECTIVES To examine temporal trends in the use of vault cytology tests in primary and secondary care and the demographics of those women tested. METHODS Retrospective analysis of routinely collected data concerning women who had a vault cytology test processed during a 10-year period (1 April 1995 to 31 March 2005) at Birmingham Women's NHS Foundation Trust. RESULTS A total of 8457 vault cytology tests from 3164 women (range 1-17 tests, median = 2) were processed, representing approximately 2% of the cervical cytology workload of the Department of Cytopathology at Birmingham Women's Hospital. There was a significant reduction in annual numbers processed (Pearson correlation -0.958, P < 0.001). Significant abnormalities (mild dyskaryosis or worse) were detected in 4.5%, with malignancy being detected in <0.1%. The unsatisfactory cytology test rate was 10.7% overall. There was a reduction in the numbers of vault cytology tests coming from the community, hospital outpatient clinics and operating theatres over time (χ(2) for linear trend = 139.53, 9 d.f., P < 0.0001). Tests originating from community settings had the lowest disease detection rates: no malignancies and only two severe abnormalities were detected from almost 4000 primary care samples; abnormal results represented 2.8% (n = 113), of which the majority (n = 73) were borderline results. All cancers (n = 8) were detected in samples taken in gynaecology and colposcopy clinics. CONCLUSIONS Vault cytology test usage appears to be reducing, particularly from outpatient clinics and primary care. Community detection rates are very low. Further research is required to establish the true costs and benefits of vaginal vault cytology.
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Affiliation(s)
- H Stokes-Lampard
- Department of Primary Care and General Practice, University of Birmingham, Primary Care Clinical Sciences Building, Edgbaston, Birmingham, UK.
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15
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Soon K, Tumur O, Brown F, Chong D, Barr S, Bentley L, Lim Y. Prospective “Step and Shoot” Scanning Mode Markedly Reduced the Radiation Dose of Coronary CTA. Heart Lung Circ 2010. [DOI: 10.1016/j.hlc.2010.06.469] [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: 10/19/2022]
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16
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Listner K, Bentley L, Okonkowski J, Kistler C, Wnek R, Caparoni A, Junker B, Robinson D, Salmon P, Chartrain M. Development of a highly productive and scalable plasmid DNA production platform. Biotechnol Prog 2007; 22:1335-45. [PMID: 17022672 DOI: 10.1021/bp060046h] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
With the applications of DNA vaccines extending from infectious diseases to cancer, achieving the most efficient, reproducible, robust, scalable, and economical production of clinical grade plasmid DNA is paramount to the medical and commercial success of this novel vaccination paradigm. A first generation production process based on the cultivation of Escherichia coli in a chemically defined medium, employing a fed-batch strategy, delivered reasonable volumetric productivities (500-750 mg/L) and proved to perform very well across a wide range of E. coli constructs upon scale-up at industrial scale. However, the presence of monosodium glutamate (MSG) in the formulation of the cultivation and feed solution was found to be a potential cause of process variability. The development of a second generation process, based on a defined cultivation medium and feed solution excluding MSG, was undertaken. Optimization studies, employing a plasmid coding for the HIV gag protein, resulted in cultivation conditions that supported volumetric plasmid titers in excess of 1.2 g/L, while achieving specific yields ranging from 25 to 32 microg plasmid DNA/mg of dry cell weight. When used for the production of clinical supplies, this novel process demonstrated applicability to two other constructs upon scale-up in 2,000-L bioreactors. This second generation process proved to be scalable, robust, and highly productive.
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Affiliation(s)
- K Listner
- Bioprocess R&D, Merck Research Laboratories, Rahway, New Jersey 07065, USA
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17
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Cornish KM, Manly T, Savage R, Swanson J, Morisano D, Butler N, Grant C, Cross G, Bentley L, Hollis CP. Association of the dopamine transporter (DAT1) 10/10-repeat genotype with ADHD symptoms and response inhibition in a general population sample. Mol Psychiatry 2005; 10:686-98. [PMID: 15809660 DOI: 10.1038/sj.mp.4001641] [Citation(s) in RCA: 169] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Association between attention-deficit hyperactivity disorder (ADHD) and the 10-repeat allele of the dopamine transporter gene (DAT1) has been reported in independent clinical samples using a categorical clinical definition of ADHD. The present study adopts a quantitative trait loci (QTL) approach to examine the association between DAT1 and a continuous measure of ADHD behaviours in a general-population sample, as well as to explore whether there is an independent association between DAT1 and performance on neuropsychological tests of attention, response inhibition, and working memory. From an epidemiological sample of 872 boys aged 6-11 years, we recruited 58 boys scoring above the 90th percentile for teacher reported ADHD symptoms (SWAN ADHD scale) and 68 boys scoring below 10th percentile for genotyping and neuropsychological testing. A significant association was found between the DAT1 homozygous 10/10-repeat genotype and high-scoring boys (chi(2)square=4.6, P<0.03; odds ratio=2.4, 95% CI 1.1-5.0). Using hierarchical linear regression, a significant independent association was found between the DAT1 10/10-repeat genotype and measures of selective attention and response inhibition after adjusting for age, IQ, and ADHD symptoms. There was no association between DAT1 and any component of working memory. Furthermore, performance on tasks of selective attention although associated with DAT1 was not associated with SWAN ADHD high scores after controlling for age and IQ. In contrast, impairment on tasks that tapped sustained attention and the central executive component of working memory were found in high-scoring boys after adjusting for age and IQ. The results suggest that DAT1 is a QTL for continuously distributed ADHD behaviours in the general population and the cognitive endophenotype of response inhibition.
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Affiliation(s)
- K M Cornish
- Neuroscience Laboratory for Research and Education in Developmental Disorders, McGill University, Montreal, Canada.
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18
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Toye AA, Lippiat JD, Proks P, Shimomura K, Bentley L, Hugill A, Mijat V, Goldsworthy M, Moir L, Haynes A, Quarterman J, Freeman HC, Ashcroft FM, Cox RD. A genetic and physiological study of impaired glucose homeostasis control in C57BL/6J mice. Diabetologia 2005; 48:675-86. [PMID: 15729571 DOI: 10.1007/s00125-005-1680-z] [Citation(s) in RCA: 312] [Impact Index Per Article: 16.4] [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: 07/22/2004] [Accepted: 11/07/2004] [Indexed: 12/19/2022]
Abstract
AIMS/HYPOTHESIS C57BL/6J mice exhibit impaired glucose tolerance. The aims of this study were to map the genetic loci underlying this phenotype, to further characterise the physiological defects and to identify candidate genes. METHODS Glucose tolerance was measured in an intraperitoneal glucose tolerance test and genetic determinants mapped in an F2 intercross. Insulin sensitivity was measured by injecting insulin and following glucose disposal from the plasma. To measure beta cell function, insulin secretion and electrophysiological studies were carried out on isolated islets. Candidate genes were investigated by sequencing and quantitative RNA analysis. RESULTS C57BL/6J mice showed normal insulin sensitivity and impaired insulin secretion. In beta cells, glucose did not stimulate a rise in intracellular calcium and its ability to close KATP channels was impaired. We identified three genetic loci responsible for the impaired glucose tolerance. Nicotinamide nucleotide transhydrogenase (Nnt) lies within one locus and is a nuclear-encoded mitochondrial proton pump. Expression of Nnt is more than sevenfold and fivefold lower respectively in C57BL/6J liver and islets. There is a missense mutation in exon 1 and a multi-exon deletion in the C57BL/6J gene. Glucokinase lies within the Gluchos2 locus and shows reduced enzyme activity in liver. CONCLUSIONS/INTERPRETATION The C57BL/6J mouse strain exhibits plasma glucose intolerance reminiscent of human type 2 diabetes. Our data suggest a defect in beta cell glucose metabolism that results in reduced electrical activity and insulin secretion. We have identified three loci that are responsible for the inherited impaired plasma glucose tolerance and identified a novel candidate gene for contribution to glucose intolerance through reduced beta cell activity.
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Affiliation(s)
- A A Toye
- Medical Research Council, Harwell, Didcot, Oxfordshire, UK
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19
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Bentley L, Nakabayashi K, Monk D, Beechey C, Peters J, Birjandi Z, Khayat FE, Patel M, Preece MA, Stanier P, Scherer SW, Moore GE. The imprinted region on human chromosome 7q32 extends to the carboxypeptidase A gene cluster: an imprinted candidate for Silver-Russell syndrome. J Med Genet 2003; 40:249-56. [PMID: 12676894 PMCID: PMC1735416 DOI: 10.1136/jmg.40.4.249] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Imprinted gene(s) on human chromosome 7q32-qter have been postulated to be involved in intrauterine growth restriction associated with Silver-Russell syndrome (SRS) as 7-10% of patients have mUPD(7). Three imprinted genes, MEST, MESTIT1, and COPG2IT1 on chromosome 7q32, are unlikely to cause SRS since epigenetic and sequence mutation analyses have not shown any changes. One hundred kilobases proximal to MEST lies a group of four carboxypeptidase A (CPA) genes. Since most imprinted genes are found in clusters, this study focuses on analysing these CPAs for imprinting effects based on their proximity to an established imprinted domain. Firstly, a replication timing study across 7q32 showed that an extensive genomic region including the CPAs, MEST, MESTIT1, and COPG2IT1 replicates asynchronously. Subsequently, SNP analysis by sequencing RT-PCR products of CPA1, CPA2, CPA4, and CPA5 indicated preferential expression of CPA4. Pyrosequencing was used as a quantitative approach, which confirmed predominantly preferential expression of the maternal allele and biallelic expression in brain. CPA5 expression levels were too low to allow reliable evaluation of allelic expression, while CPA1 and CPA2 both showed biallelic expression. CPA4 was the only gene from this family in which an imprinting effect was shown despite the location of this family of genes next to an imprinted cluster. As CPA4 has a potential role in cell proliferation and differentiation, two preferentially expressed copies in mUPD patients with SRS syndrome would result in excess expression and could alter the growth profiles of these subjects and give rise to intrauterine growth restriction.
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Affiliation(s)
- L Bentley
- Department of Fetal and Maternal Medicine, Institute of Reproductive and Developmental Biology, Faculty of Medicine, Imperial College, London, UK.
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20
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Monk D, Bentley L, Beechey C, Hitchins M, Peters J, Preece MA, Stanier P, Moore GE. Characterisation of the growth regulating gene IMP3, a candidate for Silver-Russell syndrome. J Med Genet 2002; 39:575-81. [PMID: 12161597 PMCID: PMC1735212 DOI: 10.1136/jmg.39.8.575] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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21
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Avner P, Bruls T, Poras I, Eley L, Gas S, Ruiz P, Wiles MV, Sousa-Nunes R, Kettleborough R, Rana A, Morissette J, Bentley L, Goldsworthy M, Haynes A, Herbert E, Southam L, Lehrach H, Weissenbach J, Manenti G, Rodriguez-Tome P, Beddington R, Dunwoodie S, Cox RD. A radiation hybrid transcript map of the mouse genome. Nat Genet 2001; 29:194-200. [PMID: 11586301 DOI: 10.1038/ng1001-194] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Expressed-sequence tag (EST) maps are an adjunct to sequence-based analytical methods of gene detection and localization for those species for which such data are available, and provide anchors for high-density homology and orthology mapping in species for which large-scale sequencing has yet to be done. Species for which radiation hybrid-based transcript maps have been established include human, rat, mouse, dog, cat and zebrafish. We have established a comprehensive first-generation-placement radiation hybrid map of the mouse consisting of 5,904 mapped markers (3,993 ESTs and 1,911 sequence-tagged sites (STSs)). The mapped ESTs, which often originate from small-EST clusters, are enriched for genes expressed during early mouse embryogenesis and are probably different from those localized in humans. We have confirmed by in situ hybridization that even singleton ESTs, which are usually not retained for mapping studies, may represent bona fide transcribed sequences. Our studies on mouse chromosomes 12 and 14 orthologous to human chromosome 14 show the power of our radiation hybrid map as a predictive tool for orthology mapping in humans.
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Affiliation(s)
- P Avner
- Genoscope, Centre National de Sequençage and CNRS UMR 8030, CP 5706, 91057 Evry Cedex, France.
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22
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Brouwer I, Ustin J, Bentley L, Sherman A, Dhruv N, Tendick F. Measuring in vivo animal soft tissue properties for haptic modeling in surgical simulation. Stud Health Technol Inform 2001; 81:69-74. [PMID: 11317820] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
To provide data for the design of virtual environments and teleoperated systems for surgery, it is necessary to measure tissue properties under both in vivo and ex vivo conditions. The former provides information about tissue behavior in its physiological state, while the latter can provide better control over experimental conditions. We have developed devices to measure tissue properties under extension and indentation, as well as to record instrument-tissue interaction forces. We are creating a web database of data recorded from porcine abdominal tissues.
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Affiliation(s)
- I Brouwer
- Department of Surgery, University of California, San Francisco, CA 94143-0475, USA
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23
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Doudney K, Murdoch JN, Paternotte C, Bentley L, Gregory S, Copp AJ, Stanier P. Comparative physical and transcript maps of approximately 1 Mb around loop-tail, a gene for severe neural tube defects on distal mouse chromosome 1 and human chromosome 1q22-q23. Genomics 2001; 72:180-92. [PMID: 11401431 DOI: 10.1006/geno.2000.6463] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The homozygous loop-tail (Lp) mouse has a severe neural tube closure defect, analogous to the craniorachischisis phenotype seen in humans. Linkage analysis and physical mapping have previously localized the Lp locus to a region on mouse chromosome 1 defined by the markers D1Mit113-Tagln2. Here we report the construction of sequence-ready bacterial clone contigs encompassing the Lp critical region in both mouse and the orthologous human region (1q22-q23). Twenty-two genes, one EST, and one pseudogene have been identified using a combination of EST database screening, exon amplification, and genomic sequence analysis. The preliminary gene map is Cen-Estm33-AA693056-Ly9-Cd48-Slam-Cd84-Kiaa1215-Nhlh1-Kiaa0253-Copa-Pxf-H326-Pea15-Casq1-Atp1a4-Atp1a2-Estm34-Kcnj9-Kcnj10-Kiaa1355-Tagln2-Nesg1-Crp-Tel. The genes between Slam and Kiaa1355 are positional candidates for Lp. The comparative gene content and order are identical between mouse and human, indicating a high degree of conservation between the two species in this region. Together, the physical and transcript maps described here serve as resources for the identification of the Lp mutation and further define the conservation of this genomic region between mouse and human.
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Affiliation(s)
- K Doudney
- Institute of Reproductive and Developmental Biology, Imperial College, Hammersmith Campus, Du Cane Road, London, W12 ONN, United Kingdom
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Bentley L, Fehrsen J, Jordaan F, Huismans H, du Plessis DH. Identification of antigenic regions on VP2 of African horsesickness virus serotype 3 by using phage-displayed epitope libraries. J Gen Virol 2000; 81:993-1000. [PMID: 10725425 DOI: 10.1099/0022-1317-81-4-993] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
VP2 is an outer capsid protein of African horsesickness virus (AHSV) and is recognized by serotype-discriminatory neutralizing antibodies. With the objective of locating its antigenic regions, a filamentous phage library was constructed that displayed peptides derived from the fragmentation of a cDNA copy of the gene encoding VP2. Peptides ranging in size from approximately 30 to 100 amino acids were fused with pIII, the attachment protein of the display vector, fUSE2. To ensure maximum diversity, the final library consisted of three sub-libraries. The first utilized enzymatically fragmented DNA encoding only the VP2 gene, the second included plasmid sequences, while the third included a PCR step designed to allow different peptide-encoding sequences to recombine before ligation into the vector. The resulting composite library was subjected to immunoaffinity selection with AHSV-specific polyclonal chicken IgY, polyclonal horse immunoglobulins and a monoclonal antibody (MAb) known to neutralize AHSV. Antigenic peptides were located by sequencing the DNA of phages bound by the antibodies. Most antigenic determinants capable of being mapped by this method were located in the N-terminal half of VP2. Important binding areas were mapped with high resolution by identifying the minimum overlapping areas of the selected peptides. The MAb was also used to screen a random 17-mer epitope library. Sequences that may be part of a discontinuous neutralization epitope were identified. The amino acid sequences of the antigenic regions on VP2 of serotype 3 were compared with corresponding regions on three other serotypes, revealing regions with the potential to discriminate AHSV serotypes serologically.
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Affiliation(s)
- L Bentley
- Immunology Division, Onderstepoort Veterinary Institute, Private Bag X5, Onderstepoort 0110, Republic of South Africa
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25
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Abstract
Recent evidence suggests that the surface fluid secreted by human airway epithelial cells contains antimicrobial activity. The identification of the factor(s) responsible for the antibacterial activity in airway surface fluid may bring new insights into lung defense mechanisms and the pathogenesis of disease. Defensins are small cationic peptides with broad-spectrum antimicrobial activity, and are therefore candidates for the bacterial killing factor in airway surface fluid. They are produced in mucosal epithelia and neutrophils of several species. To date no defensins have been isolated from human airway epithelia; however, such peptides are produced by bovine airway epithelia. A cDNA fragment for a human beta-defensin-1 (hBD-1) was recently cloned from the kidney. We cloned the full-length coding sequence for hBD-1 from human airway epithelia. The amino acid sequence for hBD-1 shared homology with the signal/propiece and mature peptides of other beta-defensins, including bovine tracheal antimicrobial peptide and lingual antimicrobial peptide. By Northern analysis, a single approximately 400-nt hBD-1 transcript was expressed in airway epithelia. Ribonuclease protection analysis demonstrated that hBD-1 transcripts were more abundant in the conducting airways than the gas exchange regions of human lung and that the expression was developmentally regulated. Human beta-defensin-1 may contribute to the antimicrobial activity of airway surface fluid and play a role in the mucosal defenses of the lung.
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Affiliation(s)
- P B McCray
- Department of Pediatrics, University of Iowa College of Medicine, Iowa City 52242, USA
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26
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Maddocks I, Bentley L, Sheedy J. Quality of life issues in patients dying from haematological diseases. Ann Acad Med Singap 1994; 23:244-8. [PMID: 8080225] [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: 01/28/2023]
Abstract
Patients with haematological diseases do not have ready access to hospice services in South Australia. They remain in close contact with a specialist haematology or oncology unit, and are more likely than are patients with solid tumours to receive intensive therapy during a terminal admission. The course of the final month of life was compared for three groups of patients suffering from colorectal cancer, non-Hodgkins lymphoma and acute leukaemia by a review of hospital records. All leukaemia patients died in hospital and few received a palliative care consultation. Measures of symptom control and quality of life are not recorded for these patients. It seems probable that adults with acute leukaemia will continue to die in hospital. Some of the lessons learnt from hospice practice may be appropriately applied in hospital for those patients.
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27
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Abstract
The alpha-bungarotoxin (BGT) binding protein from rat brain has been purified and its polypeptide chain composition has been examined by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Polypeptide chains with Mrs of 55,000, 53,500 and 49,000 have been identified as constituents of the protein. The affinity ligand [3H]maleimidobenzyl trimethylammonium bromide ([3H]MBTA), used to identify the ligand binding site on neuromuscular junction acetylcholine receptors (NMJ AChRs), binds to the 55,000 dalton polypeptide chain. Using a technique where ligands are bound to the protein while the protein is immobilized on alpha-cobratoxin-Sepharose 4B, it was established that the brain BGT binding protein, like NMJ AChRs, possesses two binding sites for BGT. These experiments reinforce previous evidence that the brain BGT binding protein is closely related but not identical to NMJ AChRs.
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28
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Curtis DJ, Bentley L, Weihrer A, Scott W, Brahman SL, Quillin RS. Computerized reporting: its effect on a large teaching program. Mil Med 1983; 148:248-51. [PMID: 6408507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
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Threlkeld SFH, Bentley L, Yeung A, Henriksen K. Enhanced competence in the negotiation of a T maze by Drosophila melanogaster in response to a possible food reward. CAN J ZOOL 1976. [DOI: 10.1139/z76-103] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Starved Drosophila melanogaster were run individually in a T maze in which sucrose was provided as a reward. After three trials, flies were run similarly for a fourth trial in a clean maze lacking sucrose. The time in which the food area was located in the fourth trial compared with the first was significantly decreased. Control experiments rule out the possibility that smell. pheromones, or increased energy levels associated with the ingestion of sucrose are the basis of the highly significant differences. A likely alternative is that the flies to some degree learn the location of the food area.
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