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Sriskandarajah P, McLornan DP, Oni C, Wilson AJ, Woodley C, Ciesielska M, Raj K, Dillon R, Ethell M, Chacko J, Orchard K, Radia DH. Advanced Systemic Mastocytosis with associated haematological neoplasm: Treatment with avapritinib can facilitate successful bridge to allogeneic haematopoietic cell transplant. Curr Res Transl Med 2023; 71:103398. [PMID: 37331225 DOI: 10.1016/j.retram.2023.103398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Accepted: 06/08/2023] [Indexed: 06/20/2023]
Abstract
Advanced systemic mastocytosis (AdvSM) is a rare, life-limiting mast cell (MC) neoplasm, with approximately 70% patients having an associated haematological neoplasm (AHN). Avapritinib, a selective tyrosine kinase inhibitor targeting KIT D816V, has shown potent activity translating clinically into durable responses in the phase 1 EXPLORER (NCT02561988) and phase 2 PATHFINDER (NCT03580655) studies. We report three patients with AdvSM-AHN on avapritinib who achieved complete remission (CR) of SM and were successfully bridged to allogeneic haematopoietic cell transplant (allo-HCT). Two cases additionally highlight the risk of clonal evolution within the AHN component and requirement for close monitoring while on targeted therapy.
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Affiliation(s)
- P Sriskandarajah
- Department of Haematology, Guy's and St Thomas' Hospital, London, United Kingdom.
| | - D P McLornan
- Department of Haematology, University College Hospital, London, United Kingdom
| | - C Oni
- Department of Haematology, Guy's and St Thomas' Hospital, London, United Kingdom
| | - A J Wilson
- Department of Haematology, University College Hospital, London, United Kingdom
| | - C Woodley
- Department of Haematology, Guy's and St Thomas' Hospital, London, United Kingdom
| | - M Ciesielska
- Haematology Research Department, Guy's and St Thomas' Hospital, London, United Kingdom
| | - K Raj
- Department of Haematology, University College Hospital, London, United Kingdom
| | - R Dillon
- Department of Haematology, Guy's and St Thomas' Hospital, London, United Kingdom
| | - M Ethell
- Department of Haemato-Oncology, The Royal Marsden Hospital, Sutton, United Kingdom
| | - J Chacko
- Department of Haematology, The Royal Bournemouth Hospital, Bournemouth, United Kingdom
| | - K Orchard
- Department of Haematology, Southampton General Hospital, Southampton, United Kingdom
| | - D H Radia
- Department of Haematology, Guy's and St Thomas' Hospital, London, United Kingdom
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2
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Grace RC, Carvell GE, Morton NJ, Grice M, Wilson AJ, Kemp S. On the origins of computationally complex behavior. J Exp Psychol Anim Learn Cogn 2019; 46:1-15. [PMID: 31647265 DOI: 10.1037/xan0000227] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
There is considerable evidence for computationally complex behavior, that is, behavior that appears to require the equivalent of mathematical calculation by the organism. Spatial navigation by path integration is perhaps the best example. The most influential account of such behavior has been Gallistel's (1990) computational-representational theory, which assumes that organisms represent key environmental variables such as direction and distance traveled as real numbers stored in engrams and are able to perform arithmetic computations on those representations. But how are these computations accomplished? A novel perspective is gained from the historical development of algebra. We propose that computationally complex behavior suggests that the perceptual system represents an algebraic field, which is a mathematical concept that expresses the structure underlying arithmetic. Our field representation hypothesis predicts that the perceptual system computes 2 operations on represented magnitudes, not 1. We review recent research in which human observers were trained to estimate differences and ratios of stimulus pairs in a nonsymbolic task without explicit instruction (Grace, Morton, Ward, Wilson, & Kemp, 2018). Results show that the perceptual system automatically computes two operations when comparing stimulus magnitudes. A field representation offers a resolution to longstanding controversies in psychophysics about which of 2 algebraic operations is fundamental (e.g., the Fechner-Stevens debate), overlooking the possibility that both might be. In terms of neural processes that might support computationally complex behavior, our hypothesis suggests that we should look for evidence of 2 operations and for symmetries corresponding to the additive and multiplicative groups. (PsycINFO Database Record (c) 2019 APA, all rights reserved).
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Affiliation(s)
| | | | | | - Matt Grice
- Department of Psychology, University of Canterbury
| | | | - Simon Kemp
- Department of Psychology, University of Canterbury
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3
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Moreau D, Wiebels K, Wilson AJ, Waldie KE. Volumetric and surface characteristics of gray matter in adult dyslexia and dyscalculia. Neuropsychologia 2019; 127:204-210. [PMID: 30738813 DOI: 10.1016/j.neuropsychologia.2019.02.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [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: 10/29/2018] [Revised: 02/04/2019] [Accepted: 02/04/2019] [Indexed: 01/18/2023]
Abstract
Dyslexia, dyscalculia and their comorbid manifestation are prevalent disorders associated with well-documented behavioral manifestations. However, attempts to relate these manifestations to abnormalities in brain structure have yielded mixed results, with no clear consistency across a range of measures. In this study, we used a unique design including adults with dyslexia, dyscalculia, both disorders and controls, to explore differences in gray matter characteristics across groups. Specifically, we examined whether dyslexia, dyscalculia, or their comorbid manifestation could be related to volumetric and surface characteristics of gray matter, using voxel-based and surface-based morphometry. We demonstrate with Bayesian analyses that the present data favor the null model of no differences between groups across the brain, a result that is in line with recent findings in this field of research. Importantly, we provide detailed statistical maps to enable robust assessment of our findings, and to promote cumulative evaluation of the evidence. Together, these findings suggest that gray matter differences associated with dyslexia and dyscalculia might not be as reliable as suggested by previous literature, with important implications for our understanding of these disorders.
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Affiliation(s)
- David Moreau
- School of Psychology and Centre for Brain Research, University of Auckland, New Zealand.
| | - Kristina Wiebels
- School of Psychology and Centre for Brain Research, University of Auckland, New Zealand
| | - Anna J Wilson
- Department of Psychology, University of Canterbury, New Zealand
| | - Karen E Waldie
- School of Psychology and Centre for Brain Research, University of Auckland, New Zealand
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4
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Houslay TM, Earley RL, Young AJ, Wilson AJ. Habituation and individual variation in the endocrine stress response in the Trinidadian guppy (Poecilia reticulata). Gen Comp Endocrinol 2019; 270:113-122. [PMID: 30339807 PMCID: PMC6300406 DOI: 10.1016/j.ygcen.2018.10.013] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [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: 08/21/2018] [Revised: 10/06/2018] [Accepted: 10/15/2018] [Indexed: 12/16/2022]
Abstract
The vertebrate stress response enables individuals to react to and cope with environmental challenges. A crucial aspect of the stress response is the elevation of circulating glucocorticoids. However, continued activation of the stress response under repeated exposure to stressors can be damaging to fitness. Under certain circumstances it may therefore be adaptive to habituate to repeated exposures to a particular stressor by reducing the magnitude of any associated release of glucocorticoids. Here, we investigate whether Trinidadian guppies (Poecilia reticulata) habituate to repeated exposure to a mild stressor, using a waterborne hormone sampling approach that has previously been shown to elicit a stress response in small fish. We also test for individual variation in the extent of habituation to this stressor. Concentrating on freely circulating cortisol, we found that the first exposure to the assay induced high cortisol release rates but that guppies tended to habituate quickly to subsequent exposures. There were consistent differences among individuals in their average cortisol release rate (after accounting for effects of variables such as body size) over repeated exposures. Our analyses did not find evidence of individual differences in habituation rate, although limitations in statistical power could account for this finding. We repeated the analysis for free 11-ketotestosterone, which can also respond to stressors, but found no obvious habituation pattern and no among-individual variation. We also present data on conjugated forms of both hormones, which were repeatable but did not show the expected time-lagged habituation effect. We discuss consistent individual differences around the general pattern of habituation in the flexible stress response, and highlight the potential for individual variation in habituation to facilitate selection against the deleterious effects of chronic stress.
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Affiliation(s)
- T M Houslay
- Centre for Ecology and Conservation, University of Exeter (Penryn Campus), Cornwall TR10 9FE, UK.
| | - R L Earley
- Department of Biological Sciences, University of Alabama, Biology Building 211-213, Box 870344, Tuscaloosa, AL 35487, USA.
| | - A J Young
- Centre for Ecology and Conservation, University of Exeter (Penryn Campus), Cornwall TR10 9FE, UK.
| | - A J Wilson
- Centre for Ecology and Conservation, University of Exeter (Penryn Campus), Cornwall TR10 9FE, UK.
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5
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Wilson AJ. Towards using a focussed phased array of millimetre length scale elements for ultrasound imaging. Phys Med Biol 2018; 63:145009. [PMID: 29926810 DOI: 10.1088/1361-6560/aace07] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Sparse phased array ultrasound transducers with millimetre length scale elements have previously been proposed for generating hyperthermia but not for imaging. Numerical simulation with a pseudospectral solver was used to investigate: (a) how the position of the maximum pressure in the focal region changed with element diameter and frequency; (b) how the size and position of the focal region changed with focal distance under steering; and (c) the imaging performance of 15 element random arrays. These analyses were performed for both piston-like and non piston-like millimetre diameter elements since previous work has shown a shift in the distance to the maximum pressure in the focal region with the latter. The results for these elements were compared with elements where the diameter was <λ/2. The distance from the array to the position of maximum pressure in the focal region diverged from the value with element diameter <λ/2; values for piston-like elements increased positively whilst values for non piston-like elements increased negatively. With distances expressed in λ, no difference was found for arrays at 1 MHz and 2.5 MHz. For piston-like elements, but not for non piston-like elements, two peaks were found in the focal region which were in-line with the direction of propagation for a focus on the central axis but which rotated to become parallel with the direction of propagation when steering exceeded 20°. The size and position of the focal region under steering was similar for the non piston-like elements and elements with diameter <λ/2. Little difference was found in image quality or the size of the point spread function (PSF) between images at 2.5 MHz with piston-like and non piston-like behaviour for steering angles less than 20° when compared with a linear array of similar size. These results suggest that imaging with random arrays of millimetre length scale elements is possible.
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Affiliation(s)
- A J Wilson
- Department of Physics, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, United Kingdom. Department of Research and Development, University Hospital, Coventry CV2 2DX, United Kingdom
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6
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Abstract
Intraoperative autotransfusion of whole blood was performed using the Solcotrans device in 45 patients undergoing major vascular surgery or other procedures in which there was a clean operative field. Overall, 60% of the blood shed during these operations was reinfused. Approximately 50% of patients avoided the potential complications of homologous transfusion. There were no complications attributable to the use of this device although in a sample of 13 patients, 30% of the erythrocytes were haemolysed and there were other minor haematological abnormalities. In conclusion this device provides a simple method of autotransfusing 2 or 3 litres of blood aspirated from an uncontaminated operative field.
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7
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Moreau D, Wilson AJ, McKay NS, Nihill K, Waldie KE. No evidence for systematic white matter correlates of dyslexia and dyscalculia. Neuroimage Clin 2018; 18:356-366. [PMID: 29487792 PMCID: PMC5814378 DOI: 10.1016/j.nicl.2018.02.004] [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] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Revised: 01/14/2018] [Accepted: 02/03/2018] [Indexed: 12/29/2022]
Abstract
Learning disabilities such as dyslexia, dyscalculia and their comorbid manifestation are prevalent, affecting as much as 15% of the population. Structural neuroimaging studies have indicated that these disorders can be related to differences in white matter integrity, although findings remain disparate. In this study, we used a unique design composed of individuals with dyslexia, dyscalculia, both disorders and controls, to systematically explore differences in fractional anisotropy across groups using diffusion tensor imaging. Specifically, we focused on the corona radiata and the arcuate fasciculus, two tracts associated with reading and mathematics in a number of previous studies. Using Bayesian hypothesis testing, we show that the present data favor the null model of no differences between groups for these particular tracts—a finding that seems to go against the current view but might be representative of the disparities within this field of research. Together, these findings suggest that structural differences associated with dyslexia and dyscalculia might not be as reliable as previously thought, with potential ramifications in terms of remediation. Previous literature indicates important discrepancies in structural differences associated with dyslexia and dyscalculia We explore the relationship between these disorders and fractional anisotropy, a measure of white matter integrity We show support for the null model in the corona radiata and the arcuate fasciculus This suggests that structural differences associated with these disorders are not as reliable as previously thought
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Affiliation(s)
- David Moreau
- Centre for Brain Research, School of Psychology, University of Auckland, New Zealand.
| | - Anna J Wilson
- Department of Psychology, University of Canterbury, New Zealand
| | - Nicole S McKay
- Centre for Brain Research, School of Psychology, University of Auckland, New Zealand
| | - Kasey Nihill
- School of Psychology, University of Auckland, New Zealand
| | - Karen E Waldie
- Centre for Brain Research, School of Psychology, University of Auckland, New Zealand
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8
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Khakha RS, Yasen SK, Wilson AJ. Paediatric physeal sparing posterior cruciate ligament (PCL) reconstruction with parental donation allograft: Rationale and operative approach. Knee 2018; 25:203-209. [PMID: 29343450 DOI: 10.1016/j.knee.2017.10.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Revised: 09/12/2017] [Accepted: 10/04/2017] [Indexed: 02/02/2023]
Abstract
BACKGROUND Paediatric PCL injuries are rare but constitute a significant management challenge. We describe a novel approach to the surgical management of an 11-year-old boy who presented with persisting symptomatic instability following 18months of failed conservative therapy. METHODS PCL reconstruction was performed using a physeal sparing, all-inside technique under fluoroscopic control. This avoids the potential for iatrogenic growth injury. A parentally donated hamstrings allograft was used to ensure adequate graft size, and reinforced using a non-elastic two millimetre braided suture. Graft reinforcement safeguards against stretching during the early healing phase, but must be removed thereafter to avoid creating a physeal tether. RESULTS At three months, clinical examination under anaesthesia showed equivalent PCL laxity in the operated knee compared to the normal contralateral knee. The graft reinforcement tape was incised as planned with no change in laxity assessment. Arthroscopic evaluation demonstrated a quiet joint with a well healed graft and no synovitis. Postoperative long leg radiographs showed no growth deformity against preoperative status. CONCLUSION In paediatric patients with persisting symptomatic instability despite appropriate conservative management, surgical reconstruction of the PCL should be considered. Standard treatment has higher complication rates and poorer graft survival than in an adult cohort. Specific problems include iatrogenic growth plate injury causing growth arrest or angular deformity, inadequate graft size if using hamstrings autograft, and the additional technical challenge of small patient size. Early results from extra-physeal, all-inside PCL reconstruction using a parentally donated allograft are promising and may provide an alternative solution to traditional surgical management.
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Affiliation(s)
- R S Khakha
- Basingstoke and North Hampshire Hospital, Aldermaston Road, Basingstoke RG24 9NA, United Kingdom.
| | - S K Yasen
- Basingstoke and North Hampshire Hospital, Aldermaston Road, Basingstoke RG24 9NA, United Kingdom
| | - A J Wilson
- University of Winchester, Department of Sports and Exercise Medicine, Sparkford Road, Winchester SO22 4NR, United Kingdom
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9
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Waldie KE, Wilson AJ, Roberts RP, Moreau D. Reading network in dyslexia: Similar, yet different. Brain Lang 2017; 174:29-41. [PMID: 28715717 DOI: 10.1016/j.bandl.2017.07.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [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: 09/25/2016] [Revised: 06/06/2017] [Accepted: 07/04/2017] [Indexed: 06/07/2023]
Abstract
Dyslexia is a developmental disorder characterized by reading and phonological difficulties, yet important questions remain regarding its underlying neural correlates. In this study, we used partial least squares (PLS), a multivariate analytic technique, to investigate the neural networks used by dyslexics while performing a word-rhyming task. Although the overall reading network was largely similar in dyslexics and typical readers, it did not correlate with behavior in the same way in the two groups. In particular, there was a positive association between reading performance and both right superior temporal gyrus and bilateral insula activation in dyslexic readers but a negative correlation in typical readers. Together with differences in lateralization unique to dyslexics, this suggests that the combination of poor reading performance with high insula activity and atypical laterality is a consistent marker of dyslexia. These findings emphasize the importance of understanding right-hemisphere activation in dyslexia and provide promising directions for the remediation of reading disorders.
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Affiliation(s)
- Karen E Waldie
- Centre for Brain Research, School of Psychology, The University of Auckland, New Zealand
| | - Anna J Wilson
- Department of Psychology, University of Canterbury, New Zealand
| | - Reece P Roberts
- Centre for Brain Research, School of Psychology, The University of Auckland, New Zealand
| | - David Moreau
- Centre for Brain Research, School of Psychology, The University of Auckland, New Zealand.
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10
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Brugman VA, Hernández-Triana LM, England ME, Medlock JM, Mertens PPC, Logan JG, Wilson AJ, Fooks AR, Johnson N, Carpenter S. Blood-feeding patterns of native mosquitoes and insights into their potential role as pathogen vectors in the Thames estuary region of the United Kingdom. Parasit Vectors 2017; 10:163. [PMID: 28347323 PMCID: PMC5369192 DOI: 10.1186/s13071-017-2098-4] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2016] [Accepted: 03/20/2017] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND The range of vertebrate hosts on which species of mosquito blood-feed is an important parameter for identifying potential vectors and in assessing the risk of incursion and establishment of vector-borne pathogens. In the United Kingdom, studies of mosquito host range have collected relatively few specimens and used techniques that could only broadly identify host species. This study conducted intensive collection and analysis of mosquitoes from a grazing marsh environment in southeast England. This site provides extensive wetland habitat for resident and migratory birds and has abundant human nuisance biting mosquitoes. The aim was to identify the blood-feeding patterns of mosquito species present at the site which could contribute to the transmission of pathogens. METHODS Twice-weekly collections of mosquitoes were made from Elmley Nature Reserve, Kent, between June and October 2014. Mosquitoes were collected using resting boxes, by aspiration from man-made structures and using a Mosquito Magnet Pro baited with 1-octen-3-ol. Blood-fed specimens were classified according to the degree of blood meal digestion using the Sella scale and vertebrate origin determined using sequencing of a fragment of the mitochondrial cytochrome C oxidase subunit I gene. Mosquitoes that were morphologically cryptic were identified to species level using multiplex PCR and sequencing methods. RESULTS A total of 20,666 mosquitoes of 11 species were collected, and 2,159 (10.4%) were blood-fed (Sella scale II-VI); of these 1,341 blood-fed specimens were selected for blood meal analysis. Vertebrate origin was successfully identified in 964 specimens (72%). Collections of blood-fed individuals were dominated by Anopheles maculipennis complex (73.5%), Culiseta annulata (21.2%) and Culex pipiens form pipiens (10.4%). Nineteen vertebrate hosts comprising five mammals and 14 birds were identified as hosts for mosquitoes, including two migratory bird species. Feeding on birds by Culex modestus and Anopheles atroparvus populations in England was demonstrated. CONCLUSIONS This study expands the vertebrate host range of mosquitoes in the Thames estuary region of the UK. Feeding on both resident and migratory bird species by potential arbovirus vectors including Cx. pipiens f. pipiens and Cx. modestus indicates the potential for enzootic transmission of an introduced arbovirus between migratory and local bird species by native mosquito species.
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Affiliation(s)
- V A Brugman
- The Pirbright Institute, Ash Road, Woking, Surrey, UK. .,London School of Hygiene and Tropical Medicine, Keppel Street, London, UK.
| | | | - M E England
- The Pirbright Institute, Ash Road, Woking, Surrey, UK
| | - J M Medlock
- Public Health England, Porton Down, Salisbury, UK.,Health Protection Research Unit in Emerging Infections & Zoonoses, Porton Down, Salisbury, UK
| | - P P C Mertens
- The Pirbright Institute, Ash Road, Woking, Surrey, UK.,The University of Nottingham, Sutton Bonington, Leicestershire, UK
| | - J G Logan
- London School of Hygiene and Tropical Medicine, Keppel Street, London, UK
| | - A J Wilson
- The Pirbright Institute, Ash Road, Woking, Surrey, UK
| | - A R Fooks
- Animal and Plant Health Agency, New Haw, Addlestone, Surrey, UK.,Department of Clinical Infection, Microbiology and Immunology, University of Liverpool, Liverpool, UK
| | - N Johnson
- London School of Hygiene and Tropical Medicine, Keppel Street, London, UK.,Faculty of Health and Medical Sciences, University of Surrey, Guildford, Surrey, UK
| | - S Carpenter
- The Pirbright Institute, Ash Road, Woking, Surrey, UK
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11
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Maraqa MS, Griffin R, Sharma MD, Wilson AJ, Hunt J, Hosken DJ, House CM. Constrained evolution of the sex comb in Drosophila simulans. J Evol Biol 2016; 30:388-400. [PMID: 27859860 PMCID: PMC5324616 DOI: 10.1111/jeb.13015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Revised: 11/03/2016] [Accepted: 11/07/2016] [Indexed: 11/30/2022]
Abstract
Male fitness is dependent on sexual traits that influence mate acquisition (precopulatory sexual selection) and paternity (post-copulatory sexual selection), and although many studies have documented the form of selection in one or the other of these arenas, fewer have done it for both. Nonetheless, it appears that the dominant form of sexual selection is directional, although theoretically, populations should converge on peaks in the fitness surface, where selection is stabilizing. Many factors, however, can prevent populations from reaching adaptive peaks. Genetic constraints can be important if they prevent the development of highest fitness phenotypes, as can the direction of selection if it reverses across episodes of selection. In this study, we examine the evidence that these processes influence the evolution of the multivariate sex comb morphology of male Drosophila simulans. To do this, we conduct a quantitative genetic study together with a multivariate selection analysis to infer how the genetic architecture and selection interact. We find abundant genetic variance and covariance in elements of the sex comb. However, there was little evidence for directional selection in either arena. Significant nonlinear selection was detected prior to copulation when males were mated to nonvirgin females, and post-copulation during sperm offence (again with males mated to nonvirgins). Thus, contrary to our predictions, the evolution of the D. simulans sex comb is limited neither by genetic constraints nor by antagonistic selection between pre- and post-copulatory arenas, but nonlinear selection on the multivariate phenotype may prevent sex combs from evolving to reach some fitness maximizing optima.
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Affiliation(s)
- M S Maraqa
- Centre for Ecology and Conservation, College of Life & Environmental Sciences, University of Exeter, Cornwall, UK
| | - R Griffin
- Department of Biology, University of Turku, Turun Yliopisto, Finland
| | - M D Sharma
- Centre for Ecology and Conservation, College of Life & Environmental Sciences, University of Exeter, Cornwall, UK
| | - A J Wilson
- Centre for Ecology and Conservation, College of Life & Environmental Sciences, University of Exeter, Cornwall, UK
| | - J Hunt
- School of Science and Health, Western Sydney University, Penrith, NSW, Australia
| | - D J Hosken
- Centre for Ecology and Conservation, College of Life & Environmental Sciences, University of Exeter, Cornwall, UK
| | - C M House
- School of Science and Health, Western Sydney University, Penrith, NSW, Australia
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12
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Regan CE, Pilkington JG, Bérénos C, Pemberton JM, Smiseth PT, Wilson AJ. Accounting for female space sharing in St. Kilda Soay sheep (Ovis aries) results in little change in heritability estimates. J Evol Biol 2016; 30:96-111. [PMID: 27747954 DOI: 10.1111/jeb.12990] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 09/06/2016] [Accepted: 10/06/2016] [Indexed: 02/05/2023]
Abstract
When estimating heritability in free-living populations, it is common practice to account for common environment effects, because of their potential to generate phenotypic covariance among relatives thereby biasing heritability estimates. In quantitative genetic studies of natural populations, however, philopatry, which results in relatives being clustered in space, is rarely accounted for. The two studies that have been carried out so far suggest absolute declines in heritability estimates of up to 43% when accounting for space sharing by relatives. However, due to methodological limitations these estimates may not be representative. We used data from the St. Kilda Soay sheep population to estimate heritabilities with and without accounting for space sharing for five traits for which there is evidence for additive genetic variance (birthweight, birth date, lamb August weight, and female post-mortem jaw and metacarpal length). We accounted for space sharing by related females by separately incorporating spatial autocorrelation, and a home range similarity matrix. Although these terms accounted for up to 18% of the variance in these traits, heritability estimates were only reduced by up to 7%. Our results suggest that the bias caused by not accounting for space sharing may be lower than previously thought. This suggests that philopatry does not inevitably lead to a large bias if space sharing by relatives is not accounted for. We hope our work stimulates researchers to model shared space when relatives in their study population share space, as doing so will enable us to better understand when bias may be of particular concern.
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Affiliation(s)
- C E Regan
- Institute of Evolutionary Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - J G Pilkington
- Institute of Evolutionary Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - C Bérénos
- Institute of Evolutionary Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - J M Pemberton
- Institute of Evolutionary Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - P T Smiseth
- Institute of Evolutionary Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - A J Wilson
- Centre for Ecology and Conservation, University of Exeter, Cornwall, UK
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13
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Sharma MD, Wilson AJ, Hosken DJ. Fisher's sons' effect in sexual selection: absent, intermittent or just low experimental power? J Evol Biol 2016; 29:2464-2470. [PMID: 27575647 DOI: 10.1111/jeb.12973] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [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: 03/31/2016] [Accepted: 08/28/2016] [Indexed: 11/27/2022]
Abstract
The Fisherian sexual selection paradigm has been called the null model of sexual selection. At its heart is the expectation of a genetic correlation (rG ) between female preference and male trait. However, recent meta-analysis has shown estimated correlations are often extremely weak and not statistically significant. We show here that systematic failure of studies to reject the null hypothesis that rG = 0 is almost certainly due to the low power of most experimental designs used. We provide an easy way to assess experimental power a priori and suggest that current data make it difficult to definitively test a key component of the Fisher effect.
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Affiliation(s)
- M D Sharma
- Center for Ecology and Conservation, The University of Exeter, Cornwall, UK
| | - A J Wilson
- Center for Ecology and Conservation, The University of Exeter, Cornwall, UK
| | - D J Hosken
- Center for Ecology and Conservation, The University of Exeter, Cornwall, UK
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Naydenova E, Cavendish S, Wilson AJ. Measurement and modelling the sensitivity of tetrapolar transfer impedance measurements. Med Eng Phys 2016; 38:1090-9. [PMID: 27475783 DOI: 10.1016/j.medengphy.2016.07.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [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: 12/14/2015] [Revised: 06/06/2016] [Accepted: 07/07/2016] [Indexed: 10/21/2022]
Abstract
Finite element method (FEM) modelling of a small disk in a homogeneous saline medium showed that the sensitivity distribution for tetrapolar transfer impedance measurements was dependant on the ratio, σdisk/σsaline, and not absolute conductivity values. In addition, the amplitude of the negative sensitivity regions between the drive and receive electrodes decreased non-linearly with σdisk/σsaline for σdisk/σsaline < 1, eventually becoming zero. This non-linear behaviour determined the limit of the assumption of a small change in conductivity in Geselowitz's lead theorem with 0.5 <σdisk/σsaline <1.5 for the measurements reported. The modelling supported the design of a sensitivity measurement system using an insulating support and a metal disk in a saline filled tank. Measurements were shown to give good agreement with sensitivity predictions from Geselowitz's lead theorem. Replacing the homogeneous medium in the FEM model with layers of different conductivity parallel to the plane of the electrodes changed the sensitivity distribution when the thickness of the layers adjacent to the electrodes were less than ½ the electrode spacing. A layer of greater conductivity over a layer of lesser conductivity next to the electrodes gave a peak in the sensitivity distribution and extended regions of negative sensitivity further into the tissue.
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Affiliation(s)
- E Naydenova
- Department of Physics, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK
| | - S Cavendish
- Department of Physics, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK
| | - A J Wilson
- Department of Physics, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK; Department of Clinical Physics and Bioengineering, University Hospital, Coventry CV2 2DX, UK .
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Boulton K, Rosenthal GG, Grimmer AJ, Walling CA, Wilson AJ. Sex-specific plasticity and genotype × sex interactions for age and size of maturity in the sheepshead swordtail, Xiphophorus birchmanni. J Evol Biol 2016; 29:645-56. [PMID: 26688295 PMCID: PMC5102681 DOI: 10.1111/jeb.12814] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Revised: 11/27/2015] [Accepted: 12/10/2015] [Indexed: 11/29/2022]
Abstract
Responses to sexually antagonistic selection are thought to be constrained by the shared genetic architecture of homologous male and female traits. Accordingly, adaptive sexual dimorphism depends on mechanisms such as genotype-by-sex interaction (G×S) and sex-specific plasticity to alleviate this constraint. We tested these mechanisms in a population of Xiphophorus birchmanni (sheepshead swordtail), where the intensity of male competition is expected to mediate intersexual conflict over age and size at maturity. Combining quantitative genetics with density manipulations and analysis of sex ratio variation, we confirm that maturation traits are dimorphic and heritable, but also subject to large G×S. Although cross-sex genetic correlations are close to zero, suggesting sex-linked genes with important effects on growth and maturation are likely segregating in this population, we found less evidence of sex-specific adaptive plasticity. At high density, there was a weak trend towards later and smaller maturation in both sexes. Effects of sex ratio were stronger and putatively adaptive in males but not in females. Males delay maturation in the presence of mature rivals, resulting in larger adult size with subsequent benefit to competitive ability. However, females also delay maturation in male-biased groups, incurring a loss of reproductive lifespan without apparent benefit. Thus, in highly competitive environments, female fitness may be limited by the lack of sex-specific plasticity. More generally, assuming that selection does act antagonistically on male and female maturation traits in the wild, our results demonstrate that genetic architecture of homologous traits can ease a major constraint on the evolution of adaptive dimorphism.
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Affiliation(s)
- K Boulton
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, UK
| | - G G Rosenthal
- Department of Biology, Texas A&M University, College Station, TX, USA.,Centro de Investigaciones Científicas de las Huastecas 'Aguazarca', Calnali, Hidalgo, Mexico
| | - A J Grimmer
- Centre for Ecology and Conservation, Biosciences, College of Life and Environmental Sciences, University of Exeter, Penryn, Cornwall, UK
| | - C A Walling
- Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, UK
| | - A J Wilson
- Centre for Ecology and Conservation, Biosciences, College of Life and Environmental Sciences, University of Exeter, Penryn, Cornwall, UK
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Ranade SS, Woo SH, Dubin AE, Moshourab RA, Wetzel C, Petrus M, Mathur J, Bégay V, Coste B, Mainquist J, Wilson AJ, Francisco AG, Reddy K, Qiu Z, Wood JN, Lewin GR, Patapoutian A. Piezo2 is the major transducer of mechanical forces for touch sensation in mice. Nature 2015; 516:121-5. [PMID: 25471886 DOI: 10.1038/nature13980] [Citation(s) in RCA: 538] [Impact Index Per Article: 59.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 10/17/2014] [Indexed: 01/05/2023]
Abstract
The sense of touch provides critical information about our physical environment by transforming mechanical energy into electrical signals. It is postulated that mechanically activated cation channels initiate touch sensation, but the identity of these molecules in mammals has been elusive. Piezo2 is a rapidly adapting, mechanically activated ion channel expressed in a subset of sensory neurons of the dorsal root ganglion and in cutaneous mechanoreceptors known as Merkel-cell-neurite complexes. It has been demonstrated that Merkel cells have a role in vertebrate mechanosensation using Piezo2, particularly in shaping the type of current sent by the innervating sensory neuron; however, major aspects of touch sensation remain intact without Merkel cell activity. Here we show that mice lacking Piezo2 in both adult sensory neurons and Merkel cells exhibit a profound loss of touch sensation. We precisely localize Piezo2 to the peripheral endings of a broad range of low-threshold mechanoreceptors that innervate both hairy and glabrous skin. Most rapidly adapting, mechanically activated currents in dorsal root ganglion neuronal cultures are absent in Piezo2 conditional knockout mice, and ex vivo skin nerve preparation studies show that the mechanosensitivity of low-threshold mechanoreceptors strongly depends on Piezo2. This cellular phenotype correlates with an unprecedented behavioural phenotype: an almost complete deficit in light-touch sensation in multiple behavioural assays, without affecting other somatosensory functions. Our results highlight that a single ion channel that displays rapidly adapting, mechanically activated currents in vitro is responsible for the mechanosensitivity of most low-threshold mechanoreceptor subtypes involved in innocuous touch sensation. Notably, we find that touch and pain sensation are separable, suggesting that as-yet-unknown mechanically activated ion channel(s) must account for noxious (painful) mechanosensation.
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Affiliation(s)
- Sanjeev S Ranade
- Howard Hughes Medical Institute, Molecular and Cellular Neuroscience, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Seung-Hyun Woo
- Howard Hughes Medical Institute, Molecular and Cellular Neuroscience, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Adrienne E Dubin
- Howard Hughes Medical Institute, Molecular and Cellular Neuroscience, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Rabih A Moshourab
- 1] Department of Neuroscience, Max-Delbrück Center for Molecular Medicine, Robert-Rössle Straße 10, D-13092 Berlin, Germany [2] Klinik für Anästhesiologie mit Schwerpunkt Operative Intensivmedizin, Campus Charité Mitte and Virchow-Klinikum Charité, Universitätsmedizin Berlin, Augustburgerplatz 1, 13353 Berlin, Germany
| | - Christiane Wetzel
- Department of Neuroscience, Max-Delbrück Center for Molecular Medicine, Robert-Rössle Straße 10, D-13092 Berlin, Germany
| | - Matt Petrus
- Genomics Institute of the Novartis Research Foundation, San Diego, California 92121, USA
| | - Jayanti Mathur
- Genomics Institute of the Novartis Research Foundation, San Diego, California 92121, USA
| | - Valérie Bégay
- Department of Neuroscience, Max-Delbrück Center for Molecular Medicine, Robert-Rössle Straße 10, D-13092 Berlin, Germany
| | - Bertrand Coste
- Howard Hughes Medical Institute, Molecular and Cellular Neuroscience, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, California 92037, USA
| | - James Mainquist
- Genomics Institute of the Novartis Research Foundation, San Diego, California 92121, USA
| | - A J Wilson
- Genomics Institute of the Novartis Research Foundation, San Diego, California 92121, USA
| | - Allain G Francisco
- Howard Hughes Medical Institute, Molecular and Cellular Neuroscience, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Kritika Reddy
- Howard Hughes Medical Institute, Molecular and Cellular Neuroscience, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Zhaozhu Qiu
- 1] Howard Hughes Medical Institute, Molecular and Cellular Neuroscience, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, California 92037, USA [2] Genomics Institute of the Novartis Research Foundation, San Diego, California 92121, USA
| | - John N Wood
- Molecular Nociception Group, Wolfson Institute for Biomedical Research, University College London, London WC1E 6BT, UK
| | - Gary R Lewin
- Department of Neuroscience, Max-Delbrück Center for Molecular Medicine, Robert-Rössle Straße 10, D-13092 Berlin, Germany
| | - Ardem Patapoutian
- Howard Hughes Medical Institute, Molecular and Cellular Neuroscience, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, California 92037, USA
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Wilson AJ, Andrewes SG, Struthers H, Rowe VM, Bogdanovic R, Waldie KE. Dyscalculia and dyslexia in adults: Cognitive bases of comorbidity. Learning and Individual Differences 2015. [DOI: 10.1016/j.lindif.2014.11.017] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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Wilson AJ. Competition as a source of constraint on life history evolution in natural populations. Heredity (Edinb) 2013; 112:70-8. [PMID: 23443060 DOI: 10.1038/hdy.2013.7] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2012] [Accepted: 01/15/2013] [Indexed: 11/09/2022] Open
Abstract
Competition among individuals is central to our understanding of ecology and population dynamics. However, it could also have major implications for the evolution of resource-dependent life history traits (for example, growth, fecundity) that are important determinants of fitness in natural populations. This is because when competition occurs, the phenotype of each individual will be causally influenced by the phenotypes, and so the genotypes, of competitors. Theory tells us that indirect genetic effects arising from competitive interactions will give rise to the phenomenon of 'evolutionary environmental deterioration', and act as a source of evolutionary constraint on resource-dependent traits under natural selection. However, just how important this constraint is remains an unanswered question. This article seeks to stimulate empirical research in this area, first highlighting some patterns emerging from life history studies that are consistent with a competition-based model of evolutionary constraint, before describing several quantitative modelling strategies that could be usefully applied. A recurrent theme is that rigorous quantification of a competition's impact on life history evolution will require an understanding of the causal pathways and behavioural processes by which genetic (co)variance structures arise. Knowledge of the G-matrix among life history traits is not, in and of itself, sufficient to identify the constraints caused by competition.
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Affiliation(s)
- A J Wilson
- Centre for Ecology and Conservation, University of Exeter, Cornwall, UK
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Parks CL, Rabinovich S, Tiberio PJ, Wright KJ, Yuan M, Delboy MG, Kemelman M, Wilson AJ, Powell RL, Hoffenberg S, Chiuchiolo MJ, Boggiano C, Morrow G, Lorenz IC, Jurgens CK, Zhang X, Lindsay RW, Koff WC, King CR, Caulfield MJ. Viral vector delivery of Env trimer immunogens. Retrovirology 2012. [PMCID: PMC3441608 DOI: 10.1186/1742-4690-9-s2-p341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Gubbins S, Hartemink NA, Wilson AJ, Moulin V, Vonk Noordegraaf CA, van der Sluijs MTW, de Smit AJ, Sumner T, Klinkenberg D. Scaling from challenge experiments to the field: Quantifying the impact of vaccination on the transmission of bluetongue virus serotype 8. Prev Vet Med 2012; 105:297-308. [PMID: 22425328 DOI: 10.1016/j.prevetmed.2012.02.016] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Revised: 01/25/2012] [Accepted: 02/19/2012] [Indexed: 11/18/2022]
Abstract
Bluetongue (BT) is an economically important disease of ruminants caused by bluetongue virus (BTV) and transmitted by Culicoides biting midges. The most practical and effective way to protect susceptible animals against BTV is by vaccination. Data from challenge studies in calves and sheep conducted by Intervet International b.v., in particular, presence of viral RNA in the blood of challenged animals, were used to estimate vaccine efficacy. The results of the challenge studies for calves indicated that vaccination is likely to reduce the basic reproduction number (R(0)) for BTV in cattle to below one (i.e. prevent major outbreaks within a holding) and that this reduction is robust to uncertainty in the model parameters. Sensitivity analysis showed that the whether or not vaccination is predicted to reduce R(0) to below one depended on the following assumptions: (i) whether "doubtful" results from the challenge studies are treated as negative or positive; (ii) whether or not the probability of transmission from host to vector is reduced by vaccination; and (iii) whether the extrinsic incubation period follows a realistic gamma distribution or the more commonly used exponential distribution. For sheep, all but one of the vaccinated animals were protected and, consequently, vaccination will consistently reduce R(0) in sheep to below one. Using a stochastic spatial model for the spread of BTV in Great Britain (GB), vaccination was predicted to reduce both the incidence of disease and spatial spread in simulated BTV outbreaks in GB, in both reactive vaccination strategies and when an incursion occurred into a previously vaccinated population.
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Affiliation(s)
- S Gubbins
- Institute for Animal Health, Pirbright Laboratory, Ash Road, Pirbright, Surrey GU24 0NF, UK.
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Logan JS, Elliot RR, Wilson AJ. A new technique for hamstring donor site blockade in anterior cruciate ligament reconstruction. Ann R Coll Surg Engl 2011. [PMID: 21944810 DOI: 10.1308/003588411x570909h] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- J S Logan
- Basingstoke and North Hampshire NHS Foundation Trust, UK.
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Logan JS, Elliot RR, Wilson AJ. A new technique for hamstring donor site blockade in anterior cruciate ligament reconstruction. Ann R Coll Surg Engl 2011; 93:326. [DOI: 10.1308/rcsann.2011.93.4.326b] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- JS Logan
- Basingstoke and North Hampshire NHS Foundation Trust Basingstoke, UK
| | - RR Elliot
- Basingstoke and North Hampshire NHS Foundation Trust Basingstoke, UK
| | - AJ Wilson
- Basingstoke and North Hampshire NHS Foundation Trust Basingstoke, UK
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Abstract
Many arthropod species have been transported around the globe and successfully invaded new regions. Invasive arthropods can have severe impacts on animal and human health, agriculture and forestry, and the biodiversity of natural habitats as well as those modified by humans. The economic and environmental effects of invasion can be both direct, through feeding and competition, and indirect, such as the transmission of pathogens. In this paper, the authors consider ten examples that illustrate the main mechanisms of introduction, the characteristics that enable species to rapidly expand their ranges and some of the consequences of their arrival.
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Affiliation(s)
- C J Sanders
- Institute for Animal Health, Pirbright Laboratory, Ash Road, Pirbright, Surrey GU24 0NF, United Kingdom.
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Wilson AJ, Morrissey MB, Adams MJ, Walling CA, Guinness FE, Pemberton JM, Clutton-Brock TH, Kruuk LEB. Indirect genetics effects and evolutionary constraint: an analysis of social dominance in red deer, Cervus elaphus. J Evol Biol 2011; 24:772-83. [PMID: 21288272 DOI: 10.1111/j.1420-9101.2010.02212.x] [Citation(s) in RCA: 115] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
By determining access to limited resources, social dominance is often an important determinant of fitness. Thus, if heritable, standard theory predicts mean dominance should evolve. However, dominance is usually inferred from the tendency to win contests, and given one winner and one loser in any dyadic contest, the mean proportion won will always equal 0.5. Here, we argue that the apparent conflict between quantitative genetic theory and common sense is resolved by recognition of indirect genetic effects (IGEs). We estimate selection on, and genetic (co)variance structures for, social dominance, in a wild population of red deer Cervus elaphus, on the Scottish island of Rum. While dominance is heritable and positively correlated with lifetime fitness, contest outcomes depend as much on the genes carried by an opponent as on the genotype of a focal individual. We show how this dependency imposes an absolute evolutionary constraint on the phenotypic mean, thus reconciling theoretical predictions with common sense. More generally, we argue that IGEs likely provide a widespread but poorly recognized source of evolutionary constraint for traits influenced by competition.
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Affiliation(s)
- A J Wilson
- Institute of Evolutionary Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK.
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Gratten J, Wilson AJ, McRae AF, Beraldi D, Visscher PM, Pemberton JM, Slate J. No evidence for warming climate theory of coat colour change in Soay sheep: a comment on Maloney et al. Biol Lett 2010; 6:678-9; discussion 680-1. [PMID: 20375045 DOI: 10.1098/rsbl.2010.0160] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [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)
- J Gratten
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, UK.
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Wilson AJ, Sayer RA, Edwards SG, Cartledge JD, Miller RF. A comparison of computed tomography and magnetic resonance brain imaging in HIV-positive patients with neurological symptoms. Int J STD AIDS 2010; 21:198-201. [DOI: 10.1258/ijsa.2009.009323] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
We reviewed our practice in order to determine the optimum neuroimaging strategy for HIV-infected patients with acute neurological presentations between April 2007 and August 2008. Overall magnetic resonance imaging (MRI) detected cranial abnormalities in more than twice as many patients as did computed tomography (CT) (74% and 32%, n = 54 and 38, respectively). Replacement of CT by first-line MRI for all patients would have required an additional 16 MRI scans, although at a saving of 38 CT scans. Our study highlights the importance of first-line MRI brain imaging in HIV patients with neurological symptoms and reinforces the need for early transfer of patients from centres that do not have rapid access to (or expert interpretation of) MRI scanning, to an appropriate HIV specialist centre.
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Affiliation(s)
- A J Wilson
- T8, University College London Hospitals, London NW1 8BU
- Centre for Sexual Health and HIV Research, University College London, London WC1E 6JB
| | - R A Sayer
- T8, University College London Hospitals, London NW1 8BU
- Mortimer Market Centre, Camden Provider Services PCT, London WC1E 6JB, UK
| | - S G Edwards
- T8, University College London Hospitals, London NW1 8BU
- Mortimer Market Centre, Camden Provider Services PCT, London WC1E 6JB, UK
| | - J D Cartledge
- T8, University College London Hospitals, London NW1 8BU
- Mortimer Market Centre, Camden Provider Services PCT, London WC1E 6JB, UK
| | - R F Miller
- T8, University College London Hospitals, London NW1 8BU
- Centre for Sexual Health and HIV Research, University College London, London WC1E 6JB
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Lim VK, Wilson AJ, Hamm JP, Phillips N, Iwabuchi SJ, Corballis MC, Arzarello F, Thomas MOJ. Semantic processing of mathematical gestures. Brain Cogn 2009; 71:306-12. [PMID: 19665831 DOI: 10.1016/j.bandc.2009.07.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2008] [Revised: 06/11/2009] [Accepted: 07/13/2009] [Indexed: 10/20/2022]
Abstract
OBJECTIVE To examine whether or not university mathematics students semantically process gestures depicting mathematical functions (mathematical gestures) similarly to the way they process action gestures and sentences. Semantic processing was indexed by the N400 effect. RESULTS The N400 effect elicited by words primed with mathematical gestures (e.g. "converging" and "decreasing") was the same in amplitude, latency and topography as that elicited by words primed with action gestures (e.g. drive and lift), and that for terminal words of sentences. SIGNIFICANCE AND CONCLUSION Findings provide a within-subject demonstration that the topographies of the gesture N400 effect for both action and mathematical words are indistinguishable from that of the standard language N400 effect. This suggests that mathematical function words are processed by the general language semantic system and do not appear to involve areas involved in other mathematical concepts (e.g. numerosity).
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Affiliation(s)
- Vanessa K Lim
- Department of Psychology, Research Centre for Cognitive Neuroscience, The University of Auckland, Auckland, New Zealand.
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Abstract
Susceptibility to scrapie is known to be associated with polymorphisms at the prion protein (PrP) gene, and this association is the basis of current selective programmes implemented to control scrapie in many countries. However, these programmes might have unintended consequences for other traits that might be associated with PrP genotype. The objective of this study was to investigate the relationship between PrP genotype and coat colour characteristics in two UK native sheep breeds valued for their distinctive coat colour patterns. Coat colour pattern, darkness and spotting and PrP genotype records were available for 11 674 Badgerfaced Welsh Mountain and 2338 Shetland sheep. The data were analysed with a log-linear model using maximum likelihood. Results showed a strong significant association of PrP genotype with coat colour pattern in Badgerfaced Welsh Mountain and Shetland sheep and with the presence of white spotting in Shetland sheep. Animals with the ARR/ARR genotype (the most scrapie resistant) had higher odds of having a light dorsum and a dark abdomen than the reverse pattern. The implication of these associations is that selection to increase resistance to scrapie based only on PrP genotype could result in change in morphological diversity and affect other associated traits such as fitness.
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Affiliation(s)
- R M Sawalha
- Scottish Agricultural College, Sustainable Livestock Systems, West Mains Road, Edinburgh EH93JG, UK.
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Campbell RSF, Wilson AJ. Robert Godfrey Hirst
1941-2008. Aust Vet J 2008. [DOI: 10.1111/j.1751-0813.2008.00365.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract
AIMS To assess the service quality of care as perceived by people with Type 2 diabetes mellitus. METHODS A cross-sectional survey using a self-administered questionnaire was carried out among members of Diabetes Australia-Queensland with Type 2 diabetes. For 12 aspects of service quality derived from a literature review and focus group research, patients scored the relative importance of the aspects and their perception of quality of received care. A measure of service quality was derived by combining the relative importance and actual performance. RESULTS A total of 603 people with Type 2 diabetes participated. Of the 12 aspects of care, communication, availability of support group, safety and prevention had the highest scores for importance; support group and basic amenities had the highest average performance values; but the highest service quality values were for support group, basic amenities, dignity and confidentiality. Younger participants had lower service quality scores (P = 0.001) and participants with good control of their diabetes had higher scores (P < 0.001). Compared with the reference population, our sample had 8.7% fewer people under 65 years old. CONCLUSIONS From the perspective of people with Type 2 diabetes, there is a notable gap between their expectations and what they have actually received in most aspects of provided care. In addition, overall service quality and six aspects of service quality (choice of care provider, accessibility, prevention, continuity, timeliness and safety) were identified to be of inadequate quality. Hence, this study demonstrates a significant opportunity to improve quality of healthcare services.
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Affiliation(s)
- J S Tabrizi
- Faculty of Health and Nutrition, Tabriz Medical Sciences University, Tabriz, Iran.
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Abstract
Over the last decade, there has been a rapid growth in the application of quantitative genetic techniques to evolutionary studies of natural populations. Whereas this work yields enormous insight into evolutionary processes in the wild, the use of modelling techniques and strategies adopted from animal breeders means that estimates of trait heritabilities (h(2)) are highly vulnerable to misinterpretation. Specifically, when estimated using animal models, h(2) will not generally be comparable across studies and must be interpreted as being conditioned on any fixed effects included in the model. Failure to realize the model dependency of published h(2) estimates will give a very misleading, and in most cases upwardly biased, impression of the potential for trait evolution.
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Affiliation(s)
- A J Wilson
- Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, UK.
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Morrissey MB, Wilson AJ, Pemberton JM, Ferguson MM. A framework for power and sensitivity analyses for quantitative genetic studies of natural populations, and case studies in Soay sheep (Ovis aries). J Evol Biol 2007; 20:2309-21. [PMID: 17956393 DOI: 10.1111/j.1420-9101.2007.01412.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Studies of the quantitative genetics of natural populations have contributed greatly to evolutionary biology in recent years. However, while pedigree data required are often uncertain (i.e. incomplete and partly erroneous) and limited, means to evaluate the effects of such uncertainties have not been developed. We have therefore developed a general framework for power and sensitivity analyses of such studies. We propose that researchers first generate a set of pedigree data that they wish to use in a quantitative genetic study, as well as data regarding errors that occur in that pedigree. This pedigree is then permuted using the data regarding errors to generate hypothetical 'true' and 'assumed' pedigrees that differ so as to mimic pedigree errors that might occur in the study system under consideration. Phenotypic data are then simulated across the true pedigree (according to user-defined genetic and environmental covariance structures), before being analysed with standard quantitative genetic techniques in conjunction with the 'assumed' pedigree data. To illustrate this approach, we conducted power and sensitivity analyses in a well-known study of Soay sheep (Ovis aries). We found that, although the estimation of simple genetic (co)variance structures is fairly robust to pedigree errors, some potentially serious biases were detected under more complex scenarios involving maternal effects. Power analyses also showed that this study system provides high power to detect heritabilities as low as about 0.09. Given this range of results, we suggest that such power and sensitivity analyses could greatly complement empirical studies, and we provide the computer program PEDANTICS to aid in their application.
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Affiliation(s)
- M B Morrissey
- Department of Integrative Biology, University of Guelph, Guelph, ON, Canada.
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Brook BS, Murphy CM, Breen D, Miles AW, Tilley DG, Wilson AJ. Quantification of lung injury using ventilation and perfusion distributions obtained from gamma scintigraphy. Physiol Meas 2007; 28:1451-64. [PMID: 18057511 DOI: 10.1088/0967-3334/28/12/001] [Citation(s) in RCA: 3] [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] [Indexed: 11/11/2022]
Abstract
This paper explores the potential of isotope V/Q lung scans to quantify lung disease. Areas of restricted perfusion in subjects with a pulmonary embolus (PE) were identified in 3D reconstructions of V/Q images achieved using anatomical data from the Visible Human Project. From these, the extent of lung damage was quantified. Significant differences in the values of both LogSD V and LogSD Q (p > 0.05) obtained from plots of V and Q against Log(V/Q) were found between normal subjects and subjects with a PE, but no correlation was found between either of these parameters and the degree of lung damage in subjects with a PE (p > 0.05). Whilst V/Q values were log normally distributed, the V/Q distributions from the subjects with a PE failed to show the bimodal distribution predicted from theoretical considerations and MIGET measurements previously reported. There was a statistically significant difference in the mean and standard deviation values of the V/Q distributions between normal subject and subjects with a PE (p < 0.05) but not in the median values (p > 0.05). There was no correlation between the mean, median and standard deviation of the distributions from the subjects with a PE and the percentage of damage present (p > 0.05).
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Affiliation(s)
- B S Brook
- School of Mathematical Sciences, University of Nottingham, University Park, Nottingham NG7 2RD, UK
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Abstract
BACKGROUND Theophylline and long acting beta-2 agonists are bronchodilators used for the management of persistent asthma symptoms, especially nocturnal asthma. They represent different classes of drug with differing side-effect profiles. OBJECTIVES To assess the comparative efficacy, safety and side-effects of long-acting beta-2 agonists and theophylline in the maintenance treatment of adults and adolescents with asthma. SEARCH STRATEGY We searched the Cochrane Airways Group trials register and reference lists of articles. We also contacted authors of identified RCTs for other relevant published and unpublished studies and pharmaceutical manufacturers. Most recent search: November 2006. SELECTION CRITERIA All included studies were RCTs involving adults and children with clinical evidence of asthma. These studies must have compared oral sustained release and/or dose adjusted theophylline with an inhaled long-acting beta-2 agonist. DATA COLLECTION AND ANALYSIS In original review, two reviewers independently assessed trial quality and extracted data, similarly in this update two reviewers undertook this. Study authors were contacted for additional information. MAIN RESULTS Thirteen studies with a total of 1344 participants met the inclusion criteria of the review. They were of varying quality. There was no significant difference between salmeterol and theophylline in FEV(1) predicted (6.5%; 95% CI -0.84 to 13.83). However, salmeterol treatment led to significantly better morning PEF (mean difference 16.71 L/min, 95% CI 8.91 to 24.51) and evening PEF (mean difference 15.58 L/min, 95% CI 8.33 to 22.83). Salmeterol also reduced the use of rescue medication. Formoterol, used in two studies was reported to be as effective as theophylline. Bitolterol, used in only one study, was reported to be less effective than theophylline. Participants taking salmeterol experienced fewer adverse events than those using theophylline (Parallel studies: Relative Risk 0.44; 95% CI 0.30 to 0.63, Risk Difference -0.11; 95% CI -0.16 to -0.07, Numbers Needed to Treat (NNT) 9; 95% CI 6 to 14). Significant reductions were reported for central nervous system adverse events (Relative Risk 0.50; 95% CI 0.29 to 0.86, Risk Difference -0.07; 95% CI -0.12 to -0.02, NNT 14; 95% CI 8 to 50) and gastrointestinal adverse events (Relative Risk 0.30; 95% CI 0.17 to 0.55, Risk Difference -0.11; 95% CI -0.16 to -0.06, NNT 9; 95% CI 6 to 16). AUTHORS' CONCLUSIONS Long-acting beta-2 agonists, particularly salmeterol, are more effective than theophylline in improving morning and evening PEF, but are not significantly different in their effect on FEV1. There is evidence of decreased daytime and nighttime short-acting beta-2 agonist requirement with salmeterol. Fewer adverse events occurred in participants using long-acting beta-2 agonists (salmeterol and formoterol) as compared to theophylline.
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Affiliation(s)
- A K H Tee
- Royal Melbourne Hospital, Respiratory & Sleep Medicine, Grattan Street, Parkville, Melbourne, Victoria, Australia, 3050.
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Abstract
The ability of individual organisms to alter morphological and life-history traits in response to the conditions they experience is an example of phenotypic plasticity which is fundamental to any population's ability to deal with short-term environmental change. We currently know little about the prevalence, and evolutionary and ecological causes and consequences of variation in life history plasticity in the wild. Here we outline an analytical framework, utilizing the reaction norm concept and random regression statistical models, to assess the between-individual variation in life history plasticity that may underlie population level responses to the environment at both phenotypic and genetic levels. We discuss applications of this framework to date in wild vertebrate populations, and illustrate how natural selection and ecological constraint may alter a population's response to the environment through their effects at the individual level. Finally, we present future directions and challenges for research into individual plasticity.
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Affiliation(s)
- D H Nussey
- Large Animal Research Group, Department of Zoology, University of Cambridge, Cambridge, UK.
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Wilson AJ, Pemberton JM, Pilkington JG, Coltman DW, Mifsud DV, Clutton-Brock TH, Kruuk LEB. Environmental coupling of selection and heritability limits evolution. PLoS Biol 2006; 4:e216. [PMID: 16756391 PMCID: PMC1475772 DOI: 10.1371/journal.pbio.0040216] [Citation(s) in RCA: 193] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2006] [Accepted: 04/25/2006] [Indexed: 11/18/2022] Open
Abstract
There has recently been great interest in applying theoretical quantitative genetic models to empirical studies of evolution in wild populations. However, while classical models assume environmental constancy, most natural populations exist in variable environments. Here, we applied a novel analytical technique to a long-term study of birthweight in wild sheep and examined, for the first time, how variation in environmental quality simultaneously influences the strength of natural selection and the genetic basis of trait variability. In addition to demonstrating that selection and genetic variance vary dramatically across environments, our results show that environmental heterogeneity induces a negative correlation between these two parameters. Harsh environmental conditions were associated with strong selection for increased birthweight but low genetic variance, and vice versa. Consequently, the potential for microevolution in this population is constrained by either a lack of heritable variation (in poor environments) or by a reduced strength of selection (in good environments). More generally, environmental dependence of this nature may act to limit rates of evolution, maintain genetic variance, and favour phenotypic stasis in many natural systems. Assumptions of environmental constancy are likely to be violated in natural systems, and failure to acknowledge this may generate highly misleading expectations for phenotypic microevolution.
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Affiliation(s)
- A J Wilson
- Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, United Kingdom.
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Cohen D, Plaza M, Perez-Diaz F, Lanthier O, Chauvin D, Hambourg N, Wilson AJ, Basquin M, Mazet P, Rivière JP. Individual cognitive training of reading disability improves word identification and sentence comprehension in adults with mild mental retardation. Res Dev Disabil 2006; 27:501-16. [PMID: 16198084 DOI: 10.1016/j.ridd.2004.07.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2004] [Revised: 07/02/2004] [Accepted: 07/20/2004] [Indexed: 05/04/2023]
Abstract
Reading therapy has been shown to be effective in treating reading disabilities (RD) in dyslexic children, but little is known of its use in subjects with mild mental retardation (MR). Twenty adult volunteers, with both RD and mild MR, underwent 60 consecutive weeks in a cognitive remediation program, and were compared with 32 untreated control subjects. The experimental group showed a significant improvement in word identification, as measured by oral production (p=0.0004) or silent reading (p=0.023), and sentence comprehension (p=0.0002). Adults with MR appear to benefit from new approaches in the field of RD.
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Affiliation(s)
- David Cohen
- Département de Psychiatrie de l'Enfant et de l'Adolescent, Centre Référent Langage, Groupe-Hospitalier Pitié-Salpêtrière, AP-HP, 47-83, Boulevard de l'Hôpital, 75651 Paris Cedex 13, France.
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Wilson AJ, Revkin SK, Cohen D, Cohen L, Dehaene S. An open trial assessment of "The Number Race", an adaptive computer game for remediation of dyscalculia. Behav Brain Funct 2006; 2:20. [PMID: 16734906 PMCID: PMC1523349 DOI: 10.1186/1744-9081-2-20] [Citation(s) in RCA: 127] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2006] [Accepted: 05/30/2006] [Indexed: 01/29/2023] Open
Abstract
Background In a companion article [1], we described the development and evaluation of software designed to remediate dyscalculia. This software is based on the hypothesis that dyscalculia is due to a "core deficit" in number sense or in its access via symbolic information. Here we review the evidence for this hypothesis, and present results from an initial open-trial test of the software in a sample of nine 7–9 year old children with mathematical difficulties. Methods Children completed adaptive training on numerical comparison for half an hour a day, four days a week over a period of five-weeks. They were tested before and after intervention on their performance in core numerical tasks: counting, transcoding, base-10 comprehension, enumeration, addition, subtraction, and symbolic and non-symbolic numerical comparison. Results Children showed specific increases in performance on core number sense tasks. Speed of subitizing and numerical comparison increased by several hundred msec. Subtraction accuracy increased by an average of 23%. Performance on addition and base-10 comprehension tasks did not improve over the period of the study. Conclusion Initial open-trial testing showed promising results, and suggested that the software was successful in increasing number sense over the short period of the study. However these results need to be followed up with larger, controlled studies. The issues of transfer to higher-level tasks, and of the best developmental time window for intervention also need to be addressed.
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Affiliation(s)
- Anna J Wilson
- INSERM-CEA Unit 562 « Cognitive Neuroimaging » Service Hospitalier Frédéric Joliot, CEA-DRM-DSV, 91401 Orsay, France
| | - Susannah K Revkin
- INSERM-CEA Unit 562 « Cognitive Neuroimaging » Service Hospitalier Frédéric Joliot, CEA-DRM-DSV, 91401 Orsay, France
| | - David Cohen
- Department of Child and Adolescent Psychiatry, Université Pierre et Marie Curie, Laboratoire CNRS "Du comportement et de la cognition", Hôpital Pitié-Salpêtrière, AP-HP, 47 bd de l'Hôpital, 75013, Paris, France
| | - Laurent Cohen
- INSERM-CEA Unit 562 « Cognitive Neuroimaging » Service Hospitalier Frédéric Joliot, CEA-DRM-DSV, 91401 Orsay, France
- Service de Neurologie, Hôpital de la Pitié-Salpêtrière, AP-HP, 47 bd de l'Hôpital, 75013, Paris, France
| | - Stanislas Dehaene
- INSERM-CEA Unit 562 « Cognitive Neuroimaging » Service Hospitalier Frédéric Joliot, CEA-DRM-DSV, 91401 Orsay, France
- Collège de France, 11 place Marcelin Berthelot, 75231 Paris Cedex05, France
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Wilson AJ, Dehaene S, Pinel P, Revkin SK, Cohen L, Cohen D. Principles underlying the design of "The Number Race", an adaptive computer game for remediation of dyscalculia. Behav Brain Funct 2006; 2:19. [PMID: 16734905 PMCID: PMC1550244 DOI: 10.1186/1744-9081-2-19] [Citation(s) in RCA: 115] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2005] [Accepted: 05/30/2006] [Indexed: 05/09/2023] Open
Abstract
Background Adaptive game software has been successful in remediation of dyslexia. Here we describe the cognitive and algorithmic principles underlying the development of similar software for dyscalculia. Our software is based on current understanding of the cerebral representation of number and the hypotheses that dyscalculia is due to a "core deficit" in number sense or in the link between number sense and symbolic number representations. Methods "The Number Race" software trains children on an entertaining numerical comparison task, by presenting problems adapted to the performance level of the individual child. We report full mathematical specifications of the algorithm used, which relies on an internal model of the child's knowledge in a multidimensional "learning space" consisting of three difficulty dimensions: numerical distance, response deadline, and conceptual complexity (from non-symbolic numerosity processing to increasingly complex symbolic operations). Results The performance of the software was evaluated both by mathematical simulations and by five weeks of use by nine children with mathematical learning difficulties. The results indicate that the software adapts well to varying levels of initial knowledge and learning speeds. Feedback from children, parents and teachers was positive. A companion article [1] describes the evolution of number sense and arithmetic scores before and after training. Conclusion The software, open-source and freely available online, is designed for learning disabled children aged 5–8, and may also be useful for general instruction of normal preschool children. The learning algorithm reported is highly general, and may be applied in other domains.
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Affiliation(s)
- Anna J Wilson
- INSERM-CEA Unit 562 « Cognitive Neuroimaging », Service Hospitalier Frédéric Joliot, CEA-DRM-DSV, 91401 Orsay, France
| | - Stanislas Dehaene
- INSERM-CEA Unit 562 « Cognitive Neuroimaging », Service Hospitalier Frédéric Joliot, CEA-DRM-DSV, 91401 Orsay, France
- Collège de France, 11 place Marcelin Berthelot, 75231 Paris Cedex 05, France
| | - Philippe Pinel
- INSERM-CEA Unit 562 « Cognitive Neuroimaging », Service Hospitalier Frédéric Joliot, CEA-DRM-DSV, 91401 Orsay, France
| | - Susannah K Revkin
- INSERM-CEA Unit 562 « Cognitive Neuroimaging », Service Hospitalier Frédéric Joliot, CEA-DRM-DSV, 91401 Orsay, France
| | - Laurent Cohen
- INSERM-CEA Unit 562 « Cognitive Neuroimaging », Service Hospitalier Frédéric Joliot, CEA-DRM-DSV, 91401 Orsay, France
- Service de Neurologie, Hôpital de la Pitié-Salpêtrière, AP-HP, 47 bd de l'Hôpital, 75013, Paris, France
| | - David Cohen
- Department of Child and Adolescent Psychiatry, Université Pierre et Marie Curie, Laboratoire CNRS "Du comportement et de la cognition", Hôpital Pitié-Salpêtrière, AP-HP, 47 bd de l'Hôpital, 75013, Paris, France
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Williams R, Lenz EM, Wilson AJ, Granger J, Wilson ID, Major H, Stumpf C, Plumb R. A multi-analytical platform approach to the metabonomic analysis of plasma from normal and zucker (fa/fa) obese rats. Mol BioSyst 2006; 2:174-83. [PMID: 16880935 DOI: 10.1039/b516356k] [Citation(s) in RCA: 121] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Plasma obtained from 20 week old normal Wistar-derived and Zucker (fa/fa) rats was analysed using a number of different analytical methodologies to obtain global metabolite profiles as part of metabonomic investigations of animal models of diabetes. Samples were analysed without sample pre-treatment using 1H NMR spectroscopy, after acetonitrile solvent protein precipitation by ultra-performance liquid chromatography-MS (UPLC-MS) and after acetonitrile protein precipitation and derivatisation for capillary gas chromatography-MS (GC-MS). Subsequent data analysis using principal components analysis revealed that all three analytical platforms readily detected differences between the plasma metabolite profiles of the two strains of rat. There was only limited overlap between the metabolites detected by the different methodologies and the combination of all three methods of metabolite profiling therefore provided a much more comprehensive profile than would have been provided by their use individually.
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Affiliation(s)
- R Williams
- Department of Drug Metabolism and Pharmacokinetics, AstraZeneca, Mereside, Alderley Park, Macclesfield, Cheshire, UKSK10 4TG
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Abstract
Yellow fever has been subjected to partial control for decades, but there are signs that case numbers are now increasing globally, with the risk of local epidemic outbreaks. Dengue case numbers have also increased dramatically during the past 40 years and different serotypes have invaded new geographical areas. Despite the temporal changes in these closely related diseases, and their enormous public health impact, few attempts have been made to collect a comprehensive dataset of their spatial and temporal distributions. For this review, records of the occurrence of both diseases during the 20th century have been collected together and are used to define their climatic limits using remotely sensed satellite data within a discriminant analytical model framework. The resulting risk maps for these two diseases identify their different environmental requirements, and throw some light on their potential for co-occurrence in Africa and South East Asia.
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Affiliation(s)
- D J Rogers
- TALA Research Group, Tinbergen Building, Department of Zoology, University of Oxford, South Parks Road, Oxford, UK
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Wilson AJ. New horizons in oncology. Cancer treatment: End-point evaluation. Vol. 2. Basil A. Stoll. 235 × 155 mm. Pp. 520 + xiv. Illustrated. 1983. Chichester: John Wiley & Sons Limited. £28.50. Br J Surg 2005. [DOI: 10.1002/bjs.1800710746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Wilson AJ. The Apocrine Glands and the Breast. Marshall B. L. Craigmyle. 235 ± 155 mm. Pp. 82 + ix. Illustrated in black and white and colour. 1984. Chichester: John Wiley & Sons. £24.00. Br J Surg 2005. [DOI: 10.1002/bjs.1800720644] [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: 11/10/2022]
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Wilson AJ, Coltman DW, Pemberton JM, Overall ADJ, Byrne KA, Kruuk LEB. Maternal genetic effects set the potential for evolution in a free-living vertebrate population. J Evol Biol 2005; 18:405-14. [PMID: 15715846 DOI: 10.1111/j.1420-9101.2004.00824.x] [Citation(s) in RCA: 149] [Impact Index Per Article: 7.8] [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: 11/30/2022]
Abstract
Heritable maternal effects have important consequences for the evolutionary dynamics of phenotypic traits under selection, but have only rarely been tested for or quantified in evolutionary studies. Here we estimate maternal effects on early-life traits in a feral population of Soay sheep (Ovis aries) from St Kilda, Scotland. We then partition the maternal effects into genetic and environmental components to obtain the first direct estimates of maternal genetic effects in a free-living population, and furthermore test for covariance between direct and maternal genetic effects. Using an animal model approach, direct heritabilities (h2) were low but maternal genetic effects (m2) represented a relatively large proportion of the total phenotypic variance for each trait (birth weight m2=0.119, birth date m2=0.197, natal litter size m2=0.211). A negative correlation between direct and maternal genetic effects was estimated for each trait, but was only statistically significant for natal litter size (ram= -0.714). Total heritabilities (incorporating variance from heritable maternal effects and the direct-maternal genetic covariance) were significant for birth weight and birth date but not for natal litter size. Inadequately specified models greatly overestimated additive genetic variance and hence direct h2 (by a factor of up to 6.45 in the case of birth date). We conclude that failure to model heritable maternal variance can result in over- or under-estimation of the potential for traits to respond to selection, and advocate an increased effort to explicitly measure maternal genetic effects in evolutionary studies.
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Affiliation(s)
- A J Wilson
- Institute of Cell, Animal and Population Biology, University of Edinburgh, Edinburgh, UK.
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Arango D, Wilson AJ, Shi Q, Corner GA, Arañes MJ, Nicholas C, Lesser M, Mariadason JM, Augenlicht LH. Molecular mechanisms of action and prediction of response to oxaliplatin in colorectal cancer cells. Br J Cancer 2005; 91:1931-46. [PMID: 15545975 PMCID: PMC2409767 DOI: 10.1038/sj.bjc.6602215] [Citation(s) in RCA: 175] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The platinum compound oxaliplatin has been shown to be an effective chemotherapeutic agent for the treatment of colorectal cancer. In this study, we investigate the molecular mechanisms of action of oxaliplatin to identify means of predicting response to this agent. Exposure of colon cancer cells to oxaliplatin resulted in G2/M arrest and apoptosis. Immunofluorescent staining demonstrated that the apoptotic cascade initiated by oxaliplatin is characterised by translocation of Bax to the mitochondria and cytochrome c release into the cytosol. Oxaliplatin treatment resulted in caspase 3 activation and oxaliplatin-induced apoptosis was abrogated by inhibition of caspase activity with z-VAD-fmk, but was independent of Fas/FasL association. Targeted inactivation of Bax or p53 in HCT116 cells resulted in significantly increased resistance to oxaliplatin. However, the mutational status of p53 was unable to predict response to oxaliplatin in a panel of 30 different colorectal cancer cell lines. In contrast, the expression profile of these 30 cell lines, assessed using a 9216-sequence cDNA microarray, successfully predicted the apoptotic response to oxaliplatin. A leave-one-out cross-validation approach was used to demonstrate a significant correlation between experimentally observed and expression profile predicted apoptosis in response to clinically achievable doses of oxaliplatin (R=0.53; P=0.002). In addition, these microarray experiments identified several genes involved in control of apoptosis and DNA damage repair that were significantly correlated with response to oxaliplatin.
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Affiliation(s)
- D Arango
- Oncology Department, Albert Einstein Cancer Center, Montefiore Medical Center, 111 East 210th St, Bronx, NY 10467, USA.
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Abstract
BACKGROUND Symptomatic total acromio-clavicular joint dislocation (Rockwood et al. types III-VI) may be treated by surgical reconstruction. AIM To describe an arthroscopically assisted technique to reconstruct anatomically the coraco-clavicular ligaments in acute or chronic (> 6 weeks) acromio-clavicular joint dislocation. METHODS This new technique involves arthroscopic exposure of the coracoid process. Prior to introducing this technique, cadaveric studies were undertaken. RESULTS Five patients underwent this procedure. All engaged in regular sports or manual-type work. All patients were discharged the same day with the shoulder immobilised for 4 weeks, with no heavy lifting for 3 months. All patients were pain-free at 6 weeks with full function and maximum Constant scores at 3 months. There have been no complications. CONCLUSIONS A new, safe technique is described which provides a cosmetically acceptable, anatomically solid reconstruction of the coraco-clavicular ligaments.
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Affiliation(s)
- S P Trikha
- Department of Orthopaedic Surgery, Kingston NHS Trust, Surrey, UK.
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Abstract
Recent studies in human neuroimaging, primate neurophysiology, and developmental neuropsychology indicate that the human ability for arithmetic has a tangible cerebral substrate. The human intraparietal sulcus is systematically activated in all number tasks and could host a central amodal representation of quantity. Areas of the precentral and inferior prefrontal cortex also activate when subjects engage in mental calculation. A monkey analogue of these parieto-frontal regions has recently been identified, and a neuronal population code for number has been characterized. Finally, pathologies of this system, leading to acalculia in adults or to developmental dyscalculia in children, are beginning to be understood, thus paving the way for brain-oriented intervention studies.
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Affiliation(s)
- Stanislas Dehaene
- Institut National de la Santé et de la Recherche Médicale unit 562 Cognitive neuroimaging, Service Hospitalier Frederic Joliot, Commissariat à l'énergie atomique/DRM/DSV, 4 Place du general Leclerc, 91401 Orsay cedex, France.
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