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Davidson G, Orhan AE, Lake BM. Spatial relation categorization in infants and deep neural networks. Cognition 2024; 245:105690. [PMID: 38330851 DOI: 10.1016/j.cognition.2023.105690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Revised: 12/06/2023] [Accepted: 12/07/2023] [Indexed: 02/10/2024]
Abstract
Spatial relations, such as above, below, between, and containment, are important mediators in children's understanding of the world (Piaget, 1954). The development of these relational categories in infancy has been extensively studied (Quinn, 2003) yet little is known about their computational underpinnings. Using developmental tests, we examine the extent to which deep neural networks, pretrained on a standard vision benchmark or egocentric video captured from one baby's perspective, form categorical representations for visual stimuli depicting relations. Notably, the networks did not receive any explicit training on relations. We then analyze whether these networks recover similar patterns to ones identified in development, such as reproducing the relative difficulty of categorizing different spatial relations and different stimulus abstractions. We find that the networks we evaluate tend to recover many of the patterns observed with the simpler relations of "above versus below" or "between versus outside", but struggle to match developmental findings related to "containment". We identify factors in the choice of model architecture, pretraining data, and experimental design that contribute to the extent the networks match developmental patterns, and highlight experimental predictions made by our modeling results. Our results open the door to modeling infants' earliest categorization abilities with modern machine learning tools and demonstrate the utility and productivity of this approach.
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Affiliation(s)
- Guy Davidson
- Center for Data Science, New York University, United States of America.
| | - A Emin Orhan
- Center for Data Science, New York University, United States of America
| | - Brenden M Lake
- Center for Data Science, New York University, United States of America; Department of Psychology, New York University, United States of America
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Hall A, Davidson G, Reid L. Bilateral accessory flexor indicis muscle: A case study. Morphologie 2024; 108:100716. [PMID: 37890282 DOI: 10.1016/j.morpho.2023.100716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 07/20/2023] [Accepted: 07/21/2023] [Indexed: 10/29/2023]
Abstract
Muscular variations within the upper extremities are common and widely documented. They can have a range of implications including nerve compression and misdiagnosis but are often silent. Our report herein describes a bilateral accessory muscle found in the forearm during routine cadaveric dissection. The muscle originates from the medial epicondyle of the humerus between the origins of the flexor digitorum superficialis and flexor carpi radialis muscles. The muscle is digastric, with the distal belly existing as the first lumbrical and the proximal serving as a supernumerary flexor. This functionally atavistic variation could prove clinically relevant for the purposes of donor muscle or tendon tissue as well as surgical complications and compressive neuropathies.
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Affiliation(s)
- A Hall
- Centre for Anatomy and Human Identification, School of Science and Engineering, University of Dundee, DD1 5EH Dundee, Scotland
| | - G Davidson
- Centre for Anatomy and Human Identification, School of Science and Engineering, University of Dundee, DD1 5EH Dundee, Scotland
| | - L Reid
- Centre for Anatomy and Human Identification, School of Science and Engineering, University of Dundee, DD1 5EH Dundee, Scotland.
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Taylor A, Davidson G, Boyce M, Murphy C, Doole S, Rogers C, Fraser I. Background levels of body fluids and DNA on the shaft of the penis and associated underpants in the absence of sexual activity. Sci Justice 2023; 63:529-536. [PMID: 37453785 DOI: 10.1016/j.scijus.2023.06.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 04/18/2023] [Accepted: 06/14/2023] [Indexed: 07/18/2023]
Abstract
This study examines the background of blood, saliva, semen and autosomal DNA on penile swabs and underpants from males in the absence of recent sexual activity. Based on the data collected by the AFSP Body Fluid Forum, the results of this study show that; there is a very low expectation of detecting blood on penile swabs and male underpants; a low expectation of detecting saliva on penile swabs and male underpants; and spermatozoa would be expected in less than a quarter of penile swabs and three quarters of male underpants. As none of the samples had detectable levels of DNA which were suitable for meaningful comparison that did not match the donor or their partner, the expectation of detecting a DNA profile from the cellular background on penile swabs or underpants from a male who has not been involved in recent sexual intercourse is very low. The results of this study are extremely informative when evaluating the significance of blood, saliva, semen and DNA detected on the penile swabs and underpants of males in cases of alleged sexual assault.
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Affiliation(s)
- A Taylor
- Formerly of Forensic Science Northern Ireland, 151 Belfast Road, Carrickfergus, Co. Antrim BT38 8PL, Northern Ireland
| | - G Davidson
- Cellmark Forensic Services, Buckshaw Link, Ordnance Road, Buckshaw Village, Chorley, Lancashire PR7 7EL, United Kingdom.
| | - M Boyce
- Formerly of Key Forensic Services, 207C Cavendish Place, Birchwood Park, Warrington WA3 6WU, United Kingdom
| | - C Murphy
- Department of Justice and Equality, Forensic Science Ireland, Garda Headquarters, Phoenix Park, Dublin 8, Ireland.
| | - S Doole
- Eurofins Forensic Services, Sir Alec Jeffreys Building, Peel Avenue, Calderpark, Wakefield WF2 7UA, United Kingdom.
| | - C Rogers
- SPA Forensic Services, Scottish Crime Campus, Craignethan Drive, Gartcosh G69 8AE. United Kingdom.
| | - I Fraser
- Forensic Science Northern Ireland, 151 Belfast Road, Carrickfergus, Co. Antrim BT38 8PL, Northern Ireland.
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Allard JE, Davidson G, Baird A, Boyce M, Jones S, Lewis J, Lowrie C, McBride BM. The relevance of false positive acid phosphatase reactions indicative of the presence of seminal fluid from oral and vaginal samples. Sci Justice 2023; 63:477-484. [PMID: 37453779 DOI: 10.1016/j.scijus.2023.04.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 03/27/2023] [Accepted: 04/22/2023] [Indexed: 07/18/2023]
Abstract
The Body Fluid Forum of the Association of Forensic Science Providers recognised concerns raised by forensic practitioners regarding the lack of data to inform on the incidence of significant AP (Acid Phosphatase) reactions from vaginal and oral samples, i.e. those which might be misinterpreted as indicating the presence of semen. This is particularly relevant in the light of appeal court rulings regarding the need for data to support evaluations. This paper presents collaborative data on the nature and incidence of AP reactions from vaginal and oral swabs provided by donors. The results demonstrate that caution is required with mid to strong purple AP reactions from direct testing of oral swabs and with mid purple reactions from vaginal swabs. The use of a Bayesian approach to assist with the provision of opinions regarding the presence of seminal fluid is highlighted.
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Affiliation(s)
- J E Allard
- Formerly of Forensic Science Service Ltd, 109 Lambeth Road, London SE1 7LP, United Kingdom.
| | - G Davidson
- Cellmark Forensic Services, Unit B1, Buckshaw Link, Ordnance Road, Buckshaw Village, Chorley, Lancashire PR7 7EL, United Kingdom.
| | - A Baird
- Formerly of Forensic Science Northern Ireland, 151 Belfast Road, Carrickfergus, Co. Antrim BT38 8PL, Northern Ireland
| | - M Boyce
- Formerly of Key Forensic Services, 207C Cavendish Place, Birchwood Park, Warrington WA3 6WU, United Kingdom
| | - S Jones
- SPA Forensic Services, Aberdeen, Nelson Street, Aberdeen AB24 5EQ, United Kingdom.
| | - J Lewis
- Formerly of Cellmark Forensic Services, 16 Blacklands Way, Abingdon Business Park, Abingdon, Oxfordshire OX14 1DY, United Kingdom
| | - C Lowrie
- Formerly of Eurofins Forensic Services, Building 3, Drayton Manor Business Park, Tamworth, Staffordshire B78 3GL, United Kingdom
| | - B M McBride
- Department of Justice and Equality, Forensic Science Ireland, Garda Headquarters, Phoenix Park, Dublin 8, Ireland.
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Abstract
Mood is an integrative and diffuse affective state that is thought to exert a pervasive effect on cognition and behavior. At the same time, mood itself is thought to fluctuate slowly as a product of feedback from interactions with the environment. Here we present a new computational theory of the valence of mood-the Integrated Advantage model-that seeks to account for this bidirectional interaction. Adopting theoretical formalisms from reinforcement learning, we propose to conceptualize the valence of mood as a leaky integral of an agent's appraisals of the Advantage of its actions. This model generalizes and extends previous models of mood wherein affective valence was conceptualized as a moving average of reward prediction errors. We give a full theoretical derivation of the Integrated Advantage model and provide a functional explanation of how an integrated-Advantage variable could be deployed adaptively by a biological agent to accelerate learning in complex and/or stochastic environments. Specifically, drawing on stochastic optimization theory, we propose that an agent can utilize our hypothesized form of mood to approximate a momentum-based update to its behavioral policy, thereby facilitating rapid learning of optimal actions. We then show how this model of mood provides a principled and parsimonious explanation for a number of contextual effects on mood from the affective science literature, including expectation- and surprise-related effects, counterfactual effects from information about foregone alternatives, action-typicality effects, and action/inaction asymmetry. (PsycInfo Database Record (c) 2021 APA, all rights reserved).
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Affiliation(s)
| | | | - Yael Niv
- Princeton Neuroscience Institute and Department of Psychology
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Daunt P, Ballard CG, Creese B, Davidson G, Hardy J, Oshota O, Pither RJ, Gibson AM. Polygenic Risk Scoring is an Effective Approach to Predict Those Individuals Most Likely to Decline Cognitively Due to Alzheimer's Disease. J Prev Alzheimers Dis 2020; 8:78-83. [PMID: 33336228 DOI: 10.14283/jpad.2020.64] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND There is a clear need for simple and effective tests to identify individuals who are most likely to develop Alzheimer's Disease (AD) both for the purposes of clinical trial recruitment but also for improved management of patients who may be experiencing early pre-clinical symptoms or who have clinical concerns. OBJECTIVES To predict individuals at greatest risk of progression of cognitive impairment due to Alzheimer's Disease in individuals from the Alzheimer's Disease Neuroimaging Initiative (ADNI) using a polygenic risk scoring algorithm. To compare the performance of a PRS algorithm in predicting cognitive decline against that of using the pTau/Aß1-42 ratio CSF biomarker profile. DESIGN A longitudinal analysis of data from the Alzheimer's Disease Neuroimaging Initiative study conducted across over 50 sites in the US and Canada. SETTING Multi-center genetics study. PARTICPANTS 515 subjects who upon entry to the study were diagnosed as cognitively normal or with mild cognitive impairment. MEASUREMENTS Use of genotyping and/or whole genome sequencing data to calculate polygenic risk scores and assess ability to predict subsequent cognitive decline as measured by CDR-SB and ADAS-Cog13 over 4 years. RESULTS The overall performance for predicting those individuals who would decline by at least 15 ADAS-Cog13 points from a baseline mild cognitive impairment in 4 years was 72.8% (CI:67.9-77.7) AUC increasing to 79.1% (CI: 75.6-82.6) when also including cognitively normal participants. Assessing mild cognitive impaired subjects only and using a threshold of greater than 0.6, the high genetic risk participant group declined, on average, by 1.4 points (CDR-SB) more than the low risk group over 4 years. The performance of the PRS algorithm tested was similar to that of the pTau/Aß1-42 ratio CSF biomarker profile in predicting cognitive decline. CONCLUSION Calculating polygenic risk scores offers a simple and effective way, using DNA extracted from a simple mouth swab, to select mild cognitively impaired patients who are most likely to decline cognitively over the next four years.
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Affiliation(s)
- P Daunt
- Alex Gibson, Cytox Ltd., John Eccles House, Robert Robinson Avenue, Oxford Science Park, Oxford, OX4 4GP, United Kingdom. . Tel:+44 (0)1865 338018
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Owers R, Davidson G, McDonald A, Morgan R, O’Rourke P. Time since intercourse (TSI) data from a large-scale casework study of penile–vaginal penetration allegations using Sperm Elution™. Forensic Sci Int 2018; 288:10-13. [DOI: 10.1016/j.forsciint.2018.04.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Revised: 02/23/2018] [Accepted: 04/07/2018] [Indexed: 11/28/2022]
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Booth N, Davidson G, Imperia P, Lee S, Stuart B, Thomas P, Komatsu K, Yamane R, Prescott S, Maynard-Casely H, Nelson A, Rule K. Three impossible things before lunch – the task of a sample environment specialist. JNR 2017. [DOI: 10.3233/jnr-170041] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- N. Booth
- Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights, Australia
| | - G. Davidson
- Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights, Australia
| | - P. Imperia
- Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights, Australia
| | - S. Lee
- Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights, Australia
| | - B. Stuart
- University of Technology Sydney, Ultimo, Australia
| | - P. Thomas
- University of Technology Sydney, Ultimo, Australia
| | - K. Komatsu
- Geochemical Research Center, Graduate School of Science, The University of Tokyo, Japan
| | - R. Yamane
- Geochemical Research Center, Graduate School of Science, The University of Tokyo, Japan
| | - S.W. Prescott
- School of Chemical Engineering, UNSW Australia, UNSW Sydney, NSW 2052, Australia
| | - H.E. Maynard-Casely
- Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights, Australia
| | - A. Nelson
- Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights, Australia
| | - K.C. Rule
- Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights, Australia
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10
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Gold M, Omari T, Abu-Assi R, Moore D, Heine R, Tobin JM, McCall L, Savage K, Ferris L, Kritas S, Davidson G. P34: DIAGNOSTIC MARKERS IN RELATION TO CHALLENGE-PROVEN INFANT COW’S MILK PROTEIN ALLERGY. Intern Med J 2017. [DOI: 10.1111/imj.34_13578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- M Gold
- Department of Allergy and Immunology Womens and Childrens Hospital; Adelaide Australia
| | - T Omari
- College of Medicine and Public Health; Flinders University; Adelaide Australia
| | - R Abu-Assi
- Department of Gastroenterology, Women's and Children's Hospital; Adelaide Australia
| | - D Moore
- Department of Gastroenterology, Women's and Children's Hospital; Adelaide Australia
| | - R Heine
- Murdoch Children’s Research Institute; University Melbourne; Melbourne Australia
| | - JM Tobin
- Murdoch Children’s Research Institute; University Melbourne; Melbourne Australia
| | - L McCall
- Murdoch Children’s Research Institute; University Melbourne; Melbourne Australia
| | - K Savage
- Department of Gastroenterology, Women's and Children's Hospital; Adelaide Australia
| | - L Ferris
- College of Medicine and Public Health; Flinders University; Adelaide Australia
| | - S Kritas
- Department of Gastroenterology, Women's and Children's Hospital; Adelaide Australia
| | - G Davidson
- Department of Gastroenterology, Women's and Children's Hospital; Adelaide Australia
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Ramanathan D, Guo L, Gulati T, Won S, Davidson G, Hishinuma A, Ganguly K. Enhancing low-frequency oscillations using on-demand direct-current stimulation improves motor function after stroke. Brain Stimul 2017. [DOI: 10.1016/j.brs.2017.01.523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Davidson G. A Field Study on ‘Gammexane’ and Malaria Control in the Belgian Congo. Annals of Tropical Medicine & Parasitology 2016; 44:1-26. [DOI: 10.1080/00034983.1950.11685425] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Davidson G. Field Trials with ‘Gammexane’ As a Means of Malaria Control by Adult Mosquito Destruction in Sierra Leone. Annals of Tropical Medicine & Parasitology 2016. [DOI: 10.1080/00034983.1947.11685323] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Davidson G. Field Trials with ‘Gammexane’ As a Means of Malaria Control by Adult Mosquito Destruction in Sierra Leone. Annals of Tropical Medicine & Parasitology 2016; 41:210-4. [DOI: 10.1080/00034983.1947.11685324] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Jones S, Scott K, Lewis J, Davidson G, Allard JE, Lowrie C, McBride BM, McKenna L, Teppett G, Rogers C, Clayson N, Baird A. DNA transfer through nonintimate social contact. Sci Justice 2015; 56:90-5. [PMID: 26976466 DOI: 10.1016/j.scijus.2015.10.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Revised: 10/23/2015] [Accepted: 10/30/2015] [Indexed: 11/19/2022]
Abstract
The UK and Ireland Association of Forensic Science Providers' (AFSP) Body Fluid Forum (BFF) set out to assist in the interpretation of sexual offence cases where semen is absent on vaginal swabs but female DNA is present on penile swabs or male underwear, and the issue to be addressed is whether or not sexual intercourse occurred. This study aims to investigate the frequency and amount of female DNA transferred to the penis and underwear of males following staged nonintimate social contact with females and to compare the findings with the amount of female DNA transferred to the penis and subsequently to the underwear of a male who had engaged in unprotected sexual intercourse with a female. In this study, no matching female DNA was detected on the inside front of the 44 items of male underwear used in this research following staged contact of a nonintimate nature and subsequent secondary transfer to the penis. After sexual intercourse, full profiles matching the female participant were found on the inside front of the males underwear with maximum peak heights in the range between 1898 and 3157 rfu. It was possible to demonstrate that DNA can occasionally transfer to the waistband and outside front of underwear worn by a male following staged nonintimate social contact. Data obtained in this study suggest that a matching female DNA profile below a peak height of 1000 rfu on the waistband of a male's underwear might be explained by nonintimate social contact with secondary transfer of female DNA from the male's hands.
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Affiliation(s)
- S Jones
- SPA Forensic Services, Nelson Street, Aberdeen, Scotland AB24 5EQ, United Kingdom.
| | - K Scott
- SPA Forensic Services, Nelson Street, Aberdeen, Scotland AB24 5EQ, United Kingdom
| | - J Lewis
- Cellmark Forensic Services, 16 Blacklands Way, Abingdon Business Park, Abingdon, Oxfordshire OX14 1DY, United Kingdom
| | - G Davidson
- Cellmark Forensic Services, Unit B1, Buckshaw Link, Ordnance Road, Buckshaw Village, Chorley, Lancashire PR7 7EL, United Kingdom
| | - J E Allard
- Forensic Science Service Ltd, 109 Lambeth Road, London SE1 7LP, United Kingdom(1)
| | - C Lowrie
- LGC Forensics, Building 3, Drayton Manor Business Park, Coleshill Road, Tamworth B78 3GL, United Kingdom
| | - B M McBride
- Forensic Science Laboratory, Garda Headquarters, Phoenix Park, Dublin 8, Ireland
| | - L McKenna
- Forensic Science Laboratory, Garda Headquarters, Phoenix Park, Dublin 8, Ireland
| | - G Teppett
- SPA Forensic Services, Rushton Court, 3 West Victoria Dock Road, Dundee, Scotland DD1 3JT, United Kingdom
| | - C Rogers
- SPA Forensic Services, Pitt Street, Glasgow, Scotland G2 4JS, United Kingdom
| | - N Clayson
- SPA Forensic Services, 11 Howden Hall Road, Edinburgh, Scotland EH16 6TF, United Kingdom
| | - A Baird
- Forensic Science Northern Ireland, 151 Belfast Road, Carrickfergus, County Antrim, Northern Ireland BT38 8PL, United Kingdom
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Tomas A, Bledsoe D, Wall S, Davidson G, Lascelles B. Initial evaluation of a canine stifle arthrotomy post-operative pain model. Vet J 2015; 204:293-8. [DOI: 10.1016/j.tvjl.2015.03.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Revised: 03/08/2015] [Accepted: 03/09/2015] [Indexed: 11/15/2022]
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Schmitt M, Metzger M, Gradl D, Davidson G, Orian-Rousseau V. CD44 functions in Wnt signaling by regulating LRP6 localization and activation. Cell Death Differ 2015; 22:677-89. [PMID: 25301071 PMCID: PMC4356338 DOI: 10.1038/cdd.2014.156] [Citation(s) in RCA: 112] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Revised: 07/31/2014] [Accepted: 08/18/2014] [Indexed: 11/09/2022] Open
Abstract
Wnt reception at the membrane is complex and not fully understood. CD44 is a major Wnt target gene in the intestine and is essential for Wnt-induced tumor progression in colorectal cancer. Here we show that CD44 acts as a positive regulator of the Wnt receptor complex. Downregulation of CD44 expression decreases, whereas CD44 overexpression increases Wnt activity in a concentration-dependent manner. Epistasis experiments place CD44 function at the level of the Wnt receptor LRP6. Mechanistically, CD44 physically associates with LRP6 upon Wnt treatment and modulates LRP6 membrane localization. Moreover, CD44 regulates Wnt signaling in the developing brain of Xenopus laevis embryos as shown by a decreased expression of Wnt targets tcf-4 and en-2 in CD44 morphants.
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Affiliation(s)
- M Schmitt
- Institute of Toxicology and Genetics, Karlsruhe Institute of Technology, Campus North, Postfach 3640, Karlsruhe 76021, Germany
| | - M Metzger
- Institute of Toxicology and Genetics, Karlsruhe Institute of Technology, Campus North, Postfach 3640, Karlsruhe 76021, Germany
| | - D Gradl
- Zoological Institute II, Karlsruhe Institute of Technology, Campus South, Postfach 6980, Karlsruhe 76128, Germany
| | - G Davidson
- Institute of Toxicology and Genetics, Karlsruhe Institute of Technology, Campus North, Postfach 3640, Karlsruhe 76021, Germany
| | - V Orian-Rousseau
- Institute of Toxicology and Genetics, Karlsruhe Institute of Technology, Campus North, Postfach 3640, Karlsruhe 76021, Germany
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Parkinson S, Tolbert K, Messenger K, Odunayo A, Brand M, Davidson G, Peters E, Reed A, Papich MG. Evaluation of the effect of orally administered acid suppressants on intragastric pH in cats. J Vet Intern Med 2014; 29:104-12. [PMID: 25537303 PMCID: PMC4858072 DOI: 10.1111/jvim.12493] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Revised: 09/11/2014] [Accepted: 09/23/2014] [Indexed: 01/02/2023] Open
Abstract
Background Acid suppressant drugs are a mainstay of treatment for cats with gastrointestinal erosion and ulceration. However, clinical studies have not been performed to compare the efficacy of commonly PO administered acid suppressants in cats. Hypothesis/Objectives To compare the effect of PO administered famotidine, fractionated omeprazole tablet (fOT), and omeprazole reformulated paste (ORP) on intragastric pH in cats. We hypothesized that both omeprazole formulations would be superior to famotidine and placebo. Animals Six healthy adult DSH colony cats. Methods Utilizing a randomized, 4‐way crossover design, cats received 0.88–1.26 mg/kg PO q12h fOT, ORP, famotidine, and placebo (lactose capsules). Intragastric pH monitoring was used to continuously record intragastric pH for 96 hours beginning on day 4 of treatment. Plasma omeprazole concentrations at steady state (day 7) were determined by high performance liquid chromatography (HPLC) with ultraviolet detection. Mean percentage time that intragastric pH was ≥3 and ≥4 were compared among groups using ANOVA with a posthoc Tukey‐Kramer test (α = 0.05). Results The mean percentage time ± SD that intragastric pH was ≥3 was 68.4 ± 35.0% for fOT, 73.9 ± 23.2% for ORP, 42.8 ± 18.6% for famotidine, and 16.0 ± 14.2% for placebo. Mean ± SD plasma omeprazole concentrations were similar in cats receiving fOT compared to those receiving ORP and in a range associated with acid suppression reported in other studies. Conclusions and Clinical Importance These results suggest that both omeprazole formulations provide superior acid suppression in cats compared to famotidine or placebo. Fractionated enteric‐coated OT is an effective acid suppressant despite disruption of the enteric coating.
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Affiliation(s)
- S Parkinson
- Department of Small Animal Clinical Sciences, University of Tennessee College of Veterinary Medicine, Knoxville, TN
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Loots CM, Wijnakker R, van Wijk MP, Davidson G, Benninga MA, Omari TI. Esophageal impedance baselines in infants before and after placebo and proton pump inhibitor therapy. Neurogastroenterol Motil 2012; 24:758-62, e351-2. [PMID: 22512786 DOI: 10.1111/j.1365-2982.2012.01922.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
BACKGROUND Esophageal impedance monitoring records changes in conductivity. During esophageal rest, impedance baseline values may represent mucosal integrity. The aim of this study was to assess the influence of acid suppression on impedance baselines in a placebo-controlled setting. METHODS Impedance recordings from 40 infants (0-6 months) enrolled in randomized placebo-controlled trials of proton pump inhibitor (PPI) were retrospectively analyzed. Infants underwent 24 h pH-impedance monitoring prior to and after 2 weeks of double blind therapy with placebo or a PPI. Typical clinical signs of gastro-esophageal reflux (GER) were recorded and I-GERQ-R questionnaire was completed. KEY RESULTS Median (IQR) impedance baseline increased on PPI treatment (from 1217 (826-1514) to 1903 (1560-2194) Ω, P < 0.001) but not with placebo (from 1445 (1033-1791) to 1650 (1292-1983) Ω, P = 0.13). Baselines before treatment inversely correlate with the number of GER, acid GER, weakly acid GER, acid exposure, and symptoms. The change in baseline on treatment inversely correlates with acid exposure and acid GER. Patients with initial low baselines have no improved symptomatic response to treatment. CONCLUSIONS & INFERENCES Impedance baselines are influenced by GER and increase significantly more with PPI therapy than with placebo. Clinical impact of this observation remains undefined as targeting therapy at infants with low baselines does not improve symptomatic response to treatment.
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Affiliation(s)
- C M Loots
- Department of Pediatric Gastroenterology and Nutrition, Emma Children's Hospital, Academic Medical Centre, Amsterdam, The Netherlands.
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22
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Martinez A, Davidson G, Barker C. Prevalence of Celiac Disease in Patients with Cystic Fibrosis. Paediatr Child Health 2012. [DOI: 10.1093/pch/17.suppl_a.11ab] [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: 11/13/2022] Open
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23
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Davidson G, Jalowiecki T. Acid phosphatase screening — Wetting test paper or wetting fabric and test paper? Sci Justice 2012; 52:106-11. [DOI: 10.1016/j.scijus.2011.08.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2009] [Revised: 07/31/2011] [Accepted: 08/04/2011] [Indexed: 11/30/2022]
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24
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Marshall H, Clarke M, Liew Y, Davidson G. Severity of hospitalised rotavirus gastroenteritis in South Australian children prior to and following implementation of an infant rotavirus immunisation program. Int J Infect Dis 2012. [DOI: 10.1016/j.ijid.2012.05.783] [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: 11/16/2022] Open
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25
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Wilkinson J, Davidson G. REVIEWS. Australian Feminist Studies 2012. [DOI: 10.1080/08164649.2012.648893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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26
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Murphy S, Pandraud A, Liu Y, Fawcett K, Polke JM, Davidson G, Laura M, Davis M, Houlden H, Reilly MM. 1030 Charcot-Marie-tooth disease: genetic diagnoses in a specialist clinic. J Neurol Psychiatry 2012. [DOI: 10.1136/jnnp-2011-301993.15] [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: 11/03/2022]
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Rossor A, Davidson G, Houlden H, Kalmar B, Greensmith L, Reilly M. P52 A novel p.glu175x premature stop mutation in the C-terminal end of HSP27 is a cause of CMT2. Neuromuscul Disord 2012. [DOI: 10.1016/s0960-8966(12)70060-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Wernham B, Trumpatori B, Hash J, Lipsett J, Davidson G, Wackerow P, Thomson A, Lascelles B. Dose Reduction of Meloxicam in Dogs with Osteoarthritis-Associated Pain and Impaired Mobility. J Vet Intern Med 2011; 25:1298-305. [DOI: 10.1111/j.1939-1676.2011.00825.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2011] [Revised: 07/22/2011] [Accepted: 09/16/2011] [Indexed: 11/30/2022] Open
Affiliation(s)
- B.G.J. Wernham
- Comparative Pain Research Laboratory and the Center for Comparative Medicine and Translational Research; Department of Clinical Sciences; College of Veterinary Medicine; North Carolina State University; Raleigh; NC
| | - B. Trumpatori
- Comparative Pain Research Laboratory and the Center for Comparative Medicine and Translational Research; Department of Clinical Sciences; College of Veterinary Medicine; North Carolina State University; Raleigh; NC
| | - J. Hash
- Comparative Pain Research Laboratory and the Center for Comparative Medicine and Translational Research; Department of Clinical Sciences; College of Veterinary Medicine; North Carolina State University; Raleigh; NC
| | - J. Lipsett
- Comparative Pain Research Laboratory and the Center for Comparative Medicine and Translational Research; Department of Clinical Sciences; College of Veterinary Medicine; North Carolina State University; Raleigh; NC
| | - G. Davidson
- Comparative Pain Research Laboratory and the Center for Comparative Medicine and Translational Research; Department of Clinical Sciences; College of Veterinary Medicine; North Carolina State University; Raleigh; NC
| | - P. Wackerow
- Comparative Pain Research Laboratory and the Center for Comparative Medicine and Translational Research; Department of Clinical Sciences; College of Veterinary Medicine; North Carolina State University; Raleigh; NC
| | - A. Thomson
- Comparative Pain Research Laboratory and the Center for Comparative Medicine and Translational Research; Department of Clinical Sciences; College of Veterinary Medicine; North Carolina State University; Raleigh; NC
| | - B.D.X. Lascelles
- Comparative Pain Research Laboratory and the Center for Comparative Medicine and Translational Research; Department of Clinical Sciences; College of Veterinary Medicine; North Carolina State University; Raleigh; NC
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29
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Rommel N, van Wijk M, Boets B, Hebbard G, Haslam R, Davidson G, Omari T. Development of pharyngo-esophageal physiology during swallowing in the preterm infant. Neurogastroenterol Motil 2011; 23:e401-8. [PMID: 21827583 DOI: 10.1111/j.1365-2982.2011.01763.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/07/2022]
Abstract
BACKGROUND Poor feeding is a common cause of prolonged hospitalization of preterm infants. Pharyngeal and upper esophageal sphincter (UES) function of preterm infants has been technically difficult to assess and is therefore poorly characterized. The aim of this study was to assess the development of pharyngeal motility, UES function, and their coordination during nutritive swallowing in preterm infants. METHODS Development of swallowing was assessed in 18 preterm infants. High resolution manometry was performed at first oral feeding attempt (31-32 week) and then weekly for 4 weeks. Pharyngeal and UES pressure changes were characterized in 980 swallows. KEY RESULTS During swallowing, we observed an age-related increase in peak pharyngeal pressure at the laryngeal inlet (1 cm above UES) but an age-related decrease in the time required for the UES to fully relax to nadir. Analysis of the timing of proximal pharyngeal contractile peak and UES nadir showed that the UES was not fully relaxed when bolus propulsive forces were at their peak in the youngest infants. CONCLUSIONS & INFERENCES Results show developmental changes in infant swallow physiology that can be clearly linked to the effectiveness of nutritive swallowing. Most preterm infants demonstrated poor pharyngeal pressures at the laryngeal inlet coupled with poor coordination of pharyngeal propulsion with UES relaxation. These pressure patterns were less efficient than those demonstrated by older infants who were more adept at feeding. These observations may explain why infants under 34 weeks are physiologically unable to feed effectively and experience frequent choking and fatigue during feeding.
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Affiliation(s)
- N Rommel
- Centre for Pediatric & Adolescent Gastroenterology, Children, Youth & Women's Health Service, Women's and Children's Hospital, North Adelaide (SA), Australia.
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Tolbert K, Bissett S, King A, Davidson G, Papich M, Peters E, Degernes L. Efficacy of oral famotidine and 2 omeprazole formulations for the control of intragastric pH in dogs. J Vet Intern Med 2010; 25:47-54. [PMID: 21143305 DOI: 10.1111/j.1939-1676.2010.0651.x] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
BACKGROUND Little is known about the efficacy of commonly used acid suppressants on intragastric pH in dogs. OBJECTIVE To compare the effect of oral famotidine, 2 formulations of omeprazole, and placebo on intragastric pH in dogs with a catheter-free, continuous pH monitoring system. ANIMALS Six healthy adult mixed-breed colony dogs. METHODS Utilizing a randomized, 4-way cross over, open-label study, dogs were administered famotidine PO (1.0-1.3 mg/kg q12h), omeprazole tablet (1.5-2.6 mg/kg q24h), omeprazole reformulated paste (RP) (Gastrogard, 1.5-2.6 mg/kg q24h), and placebo for 7 days followed by a 10-day washout period. Radiotelemetric pH capsules were placed with gastroscopy assistance to continuously record intragastric pH for 4 days (days 4-7 of dosing). The percentage of time that intragastric pH was ≥3 and ≥4 was compared among treatment groups using repeated measures of analysis of variance. Tukey's Studentized range test was used to determine which groups were different with α= 0.05. RESULTS Mean ± SD percent time intragastric pH was ≥3 and ≥4 was 22 ± 8% and 14 ± 6% for famotidine, 63 ± 14% and 52 ± 17% for omeprazole tablet, 54 ± 17% and 44 ± 18% for omeprazole RP, and 6 ± 6% and 5 ± 5% for placebo. Both omeprazole formulations significantly increased intragastric pH compared with famotidine and placebo, but omeprazole tablet and RP was not significantly different from each other. CONCLUSION Oral omeprazole tablet and RP provide superior gastric acid suppression to famotidine, and should therefore be considered more effective for the treatment of acid related disorders in dogs.
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Affiliation(s)
- K Tolbert
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27606, USA
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31
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Close K, Gerard M, Davidson G, Schramme M. Successful treatment of infectious (Salmonella type III: 44) polyarthritis and osteomyelitis in a 4-week-old foal. EQUINE VET EDUC 2010. [DOI: 10.1111/j.2042-3292.2010.00152.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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32
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Prestige C, Chilvers M, Davidson G, Cho E, McMahon V, White C. Increased renal hyperfiltration observed in pediatric cystic fibrosis patients. J Cyst Fibros 2010. [DOI: 10.1016/s1569-1993(10)60171-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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33
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Davidson G, Murphy S, Polke J, Davis M, Reilly M, Houlden H, collaborators of the MRC Centre f. P64 Genes for hereditary sensory and autonomic neuropathies: frequency in a UK series and genotype-phenotype correlations. Neuromuscul Disord 2010. [DOI: 10.1016/s0960-8966(10)70079-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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34
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Åsling B, Jirholt J, Hammond P, Knutsson M, Walentinsson A, Davidson G, Agreus L, Lehmann A, Lagerström-Fermer M. Collagen type III alpha I is a gastro-oesophageal reflux disease susceptibility gene and a male risk factor for hiatus hernia. Gut 2009; 58:1063-9. [PMID: 19398442 PMCID: PMC2702824 DOI: 10.1136/gut.2008.167353] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND AND OBJECTIVES Gastro-oesophageal reflux disease (GORD) is a common gastrointestinal disorder with a genetic component. Our aim was to identify genetic factors associated with GORD. PATIENTS AND METHODS Four separate patient cohorts were analysed using a step-wise approach. (1) Whole genome linkage analysis was performed in 36 families. (2) Candidate genes were tested for GORD association in a trio cohort. (3) Genetic association was replicated in a case-control cohort. We also investigated genetic association to hiatus hernia (HH). (4) Protein expression was analysed in oesophageal biopsies. RESULTS A region on chromosome 2, containing collagen type III alpha 1 (COL3A1), was identified (LOD = 3.3) in families with dominant transmission of GORD, stratified for hiatus hernia (HH). COL3A1 showed significant association with GORD in an independent paediatric trio cohort (p(corr) = 0.003). The association was male specific (p(corr) = 0.018). The COL3A1 association was replicated in an independent adult case control cohort (p(corr) = 0.022). Moreover, male specific association to HH (p(corr) = 0.019) was found for a SNP not associated to GORD. Collagen type III protein was more abundant in oesophageal biopsies from male patients with GORD (p = 0.03). CONCLUSION COL3A1 is a disease-associated gene in both paediatric and adult GORD. Furthermore, we show that COL3A1 is genetically associated with HH in adult males. The GORD- and HH-associated alleles are different, indicating two separate mechanisms leading to disease. Our data provides new insight into GORD aetiology, identifying a connective tissue component and indicating a tissue remodelling mechanism in GORD. Our results implicate gender differences in the genetic risk for both for GORD and HH.
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Affiliation(s)
- B Åsling
- AstraZeneca R&D, Mölndal, Sweden
| | | | - P Hammond
- Women’s & Children’s Hospital, Gastroenterology Unit, North Adelaide, Australia
| | | | | | - G Davidson
- Women’s & Children’s Hospital, Gastroenterology Unit, North Adelaide, Australia
| | - L Agreus
- Center for Family and Community Medicine, Karolinska Institutet, Huddinge, Sweden
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35
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Allard J, Baird A, Davidson G, Jones S, Lewis J, McKenna L, Weston C, Scrimger D, Teppett G. Erratum to ‘‘A comparison of methods used in the UK and Ireland for the extraction and detection of semen on swabs and cloth samples” [Science and Justice 47/4 (2007) 160–167]. Sci Justice 2008. [DOI: 10.1016/j.scijus.2008.01.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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36
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Allard JE, Baird A, Davidson G, Jones S, Lewis J, McKenna L, Weston C, Scrimger D, Teppett G. A comparison of methods used in the UK and Ireland for the extraction and detection of semen on swabs and cloth samples. Sci Justice 2008; 47:160-7. [PMID: 18229757 DOI: 10.1016/j.scijus.2007.09.010] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The recent formation of a United Kingdom and Irish working group, the Body Fluids Forum (BFF), highlighted the need to investigate different working practices prior to any inter-laboratory comparison work and identification of best practice. Various dilutions of semen were seeded onto swabs and cloth samples for each BFF member laboratory to test using their standard techniques. The results showed that the detection of acid phosphatase on swabs is best achieved using direct testing rather than on an extract from the swab. Extraction methods for spermatozoa require a balance to be achieved between using a sufficient volume of water to ensure optimal release and minimal volume to ensure a concentrated extract. PSA tests were investigated and found to be more sensitive than Choline. DNA profiles were obtained from samples in which no spermatozoa had been detected during microscopic examination.
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Affiliation(s)
- J E Allard
- Forensic Science Service, 109 Lambeth Road, London SE1 7LP UK.
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37
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Chandler D, Davidson G, Grant W, Greaves J, Tatchell G. Microbial biopesticides for integrated crop management: an assessment of environmental and regulatory sustainability. Trends Food Sci Technol 2008. [DOI: 10.1016/j.tifs.2007.12.009] [Citation(s) in RCA: 101] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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38
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Dorfman D, Montgomery G, George M, Davidson G, Barboza K, Bartell L, Simpson D. (332) Hypnosis for treatment of HIV neuropathic pain. The Journal of Pain 2008. [DOI: 10.1016/j.jpain.2008.01.255] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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39
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Lascelles B, Gaynor J, Smith E, Roe S, Marcellin-Little D, Davidson G, Boland E, Carr J. Amantadine in a Multimodal Analgesic Regimen for Alleviation of Refractory Osteoarthritis Pain in Dogs. J Vet Intern Med 2008; 22:53-9. [DOI: 10.1111/j.1939-1676.2007.0014.x] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
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40
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Chapman MJ, Fraser RJ, Bryant LK, Vozzo R, Nguyen NQ, Tam W, Zacharakis B, Davidson G, Butler R, Horowitz M. Gastric emptying and the organization of antro-duodenal pressures in the critically ill. Neurogastroenterol Motil 2008; 20:27-35. [PMID: 18069967 DOI: 10.1111/j.1365-2982.2007.00984.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The motor dysfunctions underlying delayed gastric emptying (GE) in critical illness are poorly defined. Our aim was to characterize the relationship between antro-duodenal (AD) motility and GE in critically ill patients. AD pressures were recorded in 15 mechanically ventilated patients and 10 healthy volunteers for 2 h (i) during fasting, (ii) following an intragastric nutrient bolus with concurrent assessment of GE using the (13)C-octanoate breath test and (iii) during duodenal nutrient infusion. Propagated waves were characterized by length and direction of migration. Critical illness was associated with: (i) slower GE (GEC: 3.47 +/- 0.1 vs 2.99 +/- 0.2; P = 0.046), (ii) fewer antegrade (duodenal: 44%vs 83%, AD: 16%vs 83%; P < 0.001) and more retrograde (duodenal: 46%vs 12%, AD: 38%vs 4%; P < 0.001) waves, (iii) shorter wave propagation (duodenal: 4.7 +/- 0.3 vs 6.0 +/- 0.4 cm; AD: 7.7 +/- 0.6 vs 10.9 +/- 0.9 cm; P = 0.004) and (iv) a close correlation between GE with the percentage of propagated phase 3 waves that were antegrade (r = 0.914, P = 0.03) and retrograde (r = -0.95, P = 0.014). In critical illness, the organization of AD pressure waves is abnormal and associated with slow GE.
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Affiliation(s)
- M J Chapman
- Intensive Care Unit, Royal Adelaide Hospital, Adelaide, SA, Australia.
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Chandler D, Davidson G. Evaluation of entomopathogenic fungus Metarhizium anisopliae against soil-dwelling stages of cabbage maggot (Diptera: Anthomyiidae) in glasshouse and field experiments and effect of fungicides on fungal activity. J Econ Entomol 2005; 98:1856-62. [PMID: 16539104 DOI: 10.1093/jee/98.6.1856] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
The effect of two isolates of the entomopathogenic fungus Metarhizium anisopliae (Metchnikoff) Sorokin (389.93 and 392.93) on root-feeding stages of cabbage root fly, Delia radicum (L.), was studied under glasshouse and field conditions. In glasshouse studies, the effect of drenching a suspension of conidia (concentration 1 x 10(8) m(-1), 40 ml per plant, applied on four occasions) onto the base of cabbage plants infested with D. radicum eggs was compared with mixing conidial suspension into compost modules (concentration 1 x 10(8) ml(-1), 25 ml per plant) used to raise seedlings. Drench application reduced the mean number of larvae and pupae recovered per plant by up to 90%, but the compost module treatment had no statistically significant effect. Both application methods reduced the emergence of adult flies from pupae by up to 92%. Most conidia applied as a drench application remained in the top 10-cm layer of compost. Applications of the fungicides iprodione and tebuconazole, which are used routinely on brassica crops, were compatible with using M. anisopliae 389.93 against D. radicum under glasshouse conditions, even though these fungicides were inhibitory to fungal growth on SDA medium. In a field experiment, drench applications of M. anisopliae 389.93 to the base of cauliflower plants at concentrations of 1 x 10(6) to 1 x 10(8) conidia ml(-1) did not control D. radicum populations, although up to 30% of larval cadavers recovered supported sporulating mycelium. Drench applications often exhibited considerable lateral movement on the soil surface before penetrating the ground, which may have reduced the amount of inoculum in contact with D. radicum larvae.
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Affiliation(s)
- D Chandler
- Warwick HRI, University of Warwick, Wellesbourne, Warwick CV35 9EF, United Kingdom
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43
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Davidson G, Pizzari T, Mayes S. 162 Stress fractures of the base of the second metatarsal in elite female classical dancers. J Sci Med Sport 2005. [DOI: 10.1016/s1440-2440(17)30657-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Davidson G, Chandler D. Laboratory evaluation of entomopathogenic fungi against larvae and adults of onion maggot (Diptera: Anthomyiidae). J Econ Entomol 2005; 98:1848-55. [PMID: 16539103 DOI: 10.1093/jee/98.6.1848] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Laboratory experiments were done to measure the susceptibility of larvae and adults of the onion maggot, Delia antiqua (Meigen) (Diptera: Muscidae: Anthomyiidae) to 27 isolates of entomopathogenic fungi from four genera [Beauveria Vuillemin, Lecanicillium (Petch) Zare & W. Gams, Metarhizium Sorokin, and Paecilomyces Bainier]. A novel bioassay was developed for D. antiqua larvae by using a diet based on mixed vegetable powder. When evaluated in a virulence screen, the fungal isolates caused less mortality of D. antiqua larvae than adults. Only three isolates caused > 50% mortality of larvae, whereas 12 isolates caused > 50% mortality of adults. Fungal species was a statistically significant factor affecting the mortality of larvae but not of adults. The fungal isolates causing the most mortality of larvae tended to belong to Metarhizium anisopliae (Metschnikoff) Sorokin. Two M. anisopliae isolates (389.93 and 392.93) were evaluated in dose-response bioassays. The median lethal concentrations of the isolates against larvae were 6.1 x 10(7) conidia ml(-1) for isolate 389.93 and 7.6 x 10(7) conidia ml(-1) for isolate 392.93. The emergence of adult flies from pupae was reduced at high concentrations of conidia (3.0 x 10(8) and 1.0 x 10(8) conidia ml(-1)). The median lethal concentrations of the isolates against adults were 1.7 x 10(7) and 4.0 x 10(7) conidia ml(-1), respectively. Some of the fungal isolates examined may have potential as biological control agents of larvae of D. antiqua and related species.
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Affiliation(s)
- G Davidson
- Warwick HRI, University of Warwick, Wellesbourne, Warwick CV35 9EF, United Kingdom
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45
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Chapman M, Fraser R, Vozzo R, Bryant L, Tam W, Nguyen N, Zacharakis B, Butler R, Davidson G, Horowitz M. Antro-pyloro-duodenal motor responses to gastric and duodenal nutrient in critically ill patients. Gut 2005; 54:1384-90. [PMID: 15923669 PMCID: PMC1774690 DOI: 10.1136/gut.2005.065672] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Revised: 03/30/2005] [Accepted: 04/12/2005] [Indexed: 02/07/2023]
Abstract
BACKGROUND Gastric emptying is frequently delayed in critical illness which compromises the success of nasogastric nutrition. The underlying motor dysfunctions are poorly defined. AIMS To characterise antro-pyloro-duodenal motility during fasting, and in response to gastric and duodenal nutrient, as well as to evaluate the relationship between gastric emptying and motility, in the critically ill. SUBJECTS Fifteen mechanically ventilated patients from a mixed intensive care unit; 10 healthy volunteers. METHODS Antro-pyloro-duodenal pressures were recorded during fasting, after intragastric administration (100 ml; 100 kcal), and during small intestinal infusion of liquid nutrient (6 hours; 1 kcal/min). Gastric emptying was measured using a (13)C octanoate breath test. RESULTS In healthy subjects, neither gastric nor small intestinal nutrient affected antro-pyloro-duodenal pressures. In patients, duodenal nutrient infusion reduced antral activity compared with both fasting and healthy subjects (0.03 (0-2.47) waves/min v 0.14 (0-2.2) fasting (p = 0.016); and v 0.33 (0-2.57)/min in healthy subjects (p = 0.005)). Basal pyloric pressure and the frequency of phasic pyloric pressure waves were increased in patients during duodenal nutrient infusion (3.12 (1.06) mm Hg; 0.98 (0.13)/min) compared with healthy subjects (-0.44 (1.25) mm Hg; p<0.02 after 120 minutes; 0.29 (0.15)/min; p = 0.0002) and with fasting (-0.06 (1.05) mm Hg; p<0.03 after 160 minutes; 0.49 (0.13)/min; (p = 0.0001). Gastric emptying was delayed in patients (gastric emptying coefficient 2.99 (0.2) v 3.47 (0.1); p = 0.015) and inversely related to the number of pyloric pressure waves (r = -0.563, p = 0.029). CONCLUSIONS Stimulation of pyloric and suppression of antral pressures by duodenal nutrient are enhanced in the critically ill and related to decreased gastric emptying.
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Affiliation(s)
- M Chapman
- Intensive Care Unit, Royal Adelaide Hospital, North Terrace, Adelaide, Australia.
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Davidson G, Dillon KB. Nuclear quadrupole resonance spectroscopy. Spectroscopic Properties of Inorganic and Organometallic Compounds 2005. [DOI: 10.1039/9781847555212-00001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Davidson G, Phelps K, Sunderland KD, Pell JK, Ball BV, Shaw KE, Chandler D. Study of temperature-growth interactions of entomopathogenic fungi with potential for control of Varroa destructor (Acari: Mesostigmata) using a nonlinear model of poikilotherm development. J Appl Microbiol 2003; 94:816-25. [PMID: 12694446 DOI: 10.1046/j.1365-2672.2003.01871.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.0] [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: 11/20/2022]
Abstract
AIMS To investigate the thermal biology of entomopathogenic fungi being examined as potential microbial control agents of Varroa destructor, an ectoparasite of the European honey bee Apis mellifera. METHODS AND RESULTS Colony extension rates were measured at three temperatures (20, 30 and 35 degrees C) for 41 isolates of entomopathogenic fungi. All of the isolates grew at 20 and 30 degrees C but only 11 isolates grew at 35 degrees C. Twenty-two isolates were then selected on the basis of appreciable growth at 30-35 degrees C (the temperature range found within honey bee colonies) and/or infectivity to V. destructor, and their colony extension rates were measured at 10 temperatures (12.5-35 degrees C). This data were then fitted to Schoolfield et al. [J Theor Biol (1981)88:719-731] re-formulation of the Sharpe and DeMichele [J Theor Biol (1977)64:649-670] model of poikilotherm development. Overall, this model accounted for 87.6-93.9% of the data variance. Eleven isolates exhibited growth above 35 degrees C. The optimum temperatures for extension rate ranged from 22.9 to 31.2 degrees C. Only three isolates exhibited temperature optima above 30 degrees C. The super-optimum temperatures (temperature above the optimum at which the colony extension rate was 10% of the maximum rate) ranged from 31.9 to 43.2 degrees C. CONCLUSIONS The thermal requirements of the isolates examined against V. destructor are well matched to the temperatures in the broodless areas of honey bee colonies, and a proportion of isolates, should also be able to function within drone brood areas. SIGNIFICANCE AND IMPACT OF THE STUDY Potential exists for the control of V. destructor with entomopathogenic fungi in honey bee colonies. The methods employed in this study could be utilized in the selection of isolates for microbial control prior to screening for infectivity and could help in predicting the activity of a fungal control agent of V. destructor under fluctuating temperature conditions.
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Affiliation(s)
- G Davidson
- Horticulture Research International, Wellesbourne, Warwick, UK.
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Chapman M, Fraser R, de Beaux I, Creed S, Finnis M, Butler R, Cmielewski P, Zacharkis B, Davidson G. Cefazolin does not accelerate gastric emptying in the critically ill. Intensive Care Med 2003; 29:1169-72. [PMID: 12802484 DOI: 10.1007/s00134-003-1803-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2002] [Accepted: 08/02/2002] [Indexed: 01/15/2023]
Abstract
OBJECTIVE To evaluate the effect of intravenous cefazolin on gastric emptying measured by the C-13 octanoic acid breath test. DESIGN Prospective, double-blind, cross-over, randomised, placebo-controlled trial. SETTING Mixed multidisciplinary intensive care unit in a university hospital. PATIENTS Fourteen critically ill, mechanically ventilated patients. INTERVENTIONS After a 4-h fast patients received either 50 mg cefazolin or 20 ml saline over 20 min immediately prior to measurement of gastric emptying. The next day the study was repeated with the alternative therapy. MEASUREMENTS AND RESULTS Breath samples were analysed for the concentration of (13)CO2 by mass spectrometer, and the gastric emptying coefficient (GEC) and half-emptying time (t(50)) were calculated. Results are mean (standard deviation). Data were analysed with the paired t-test (saline vs cefazolin). Two patients were excluded for technical problems. Twelve patients remained (six male/six female), aged 57 (+/-16) years, with an APACHE II score of 20 (+/-8). Both GEC and t(50) were unchanged after administration of cefazolin compared with placebo (t(50) cefazolin, 138 (+/-54) vs saline 122 (+/-46) min, P=0.32; GEC cefazolin 3.27 (+/-0.83) vs saline 3.55 (+/-0.6), P=0.24). Two patients had abnormal t(50) after saline and five after cefazolin. There was no order effect of the study day. CONCLUSION In mechanically ventilated patients, cefazolin had no effect on gastric emptying. These data do not support the use of low-dose cefazolin as a pro-kinetic agent in critically ill patients.
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Affiliation(s)
- M Chapman
- Intensive Care Unit, Royal Adelaide Hospital, North Terrace, SA 5000, Adelaide, Australia.
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Call KT, Davidson G, Sommers AS, Feldman R, Farseth P, Rockwood T. Uncovering the missing Medicaid cases and assessing their bias for estimates of the uninsured. Inquiry 2002; 38:396-408. [PMID: 11887957 DOI: 10.5034/inquiryjrnl_38.4.396] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
General population surveys of health insurance coverage are thought to undercount Medicaid enrollment, which may bias estimates of the uninsured. This article describes the results of an experiment undertaken in conjunction with a general population survey in Minnesota. Responses to health insurance questions by a known sample of public program enrollees are analyzed to determine possible reasons for the undercount and the amount of bias introduced in estimates of uninsured people. While public program enrollees often misreport the type of coverage they have, the impact on estimates of those without insurance is negligible. Restrictions to generalizing the finding beyond this study are discussed.
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Affiliation(s)
- K T Call
- Division of Health Services Research and Policy, School of Public Health, University of Minnesota, Minneapolis 55455, USA
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Magnuson TS, Isoyama N, Hodges-Myerson AL, Davidson G, Maroney MJ, Geesey GG, Lovley DR. Isolation, characterization and gene sequence analysis of a membrane-associated 89 kDa Fe(III) reducing cytochrome c from Geobacter sulfurreducens. Biochem J 2001; 359:147-52. [PMID: 11563978 PMCID: PMC1222130 DOI: 10.1042/0264-6021:3590147] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Geobacter sulfurreducens is capable of anaerobic respiration with Fe(III) as a terminal electron acceptor via a membrane-bound Fe(III) reductase activity associated with a large molecular mass cytochrome c. This cytochrome was purified by detergent extraction of the membrane fraction, Q-Sepharose ion-exchange chromatography, preparative electrophoresis, and MonoQ ion-exchange chromatography. Spectrophotometric analysis of the purified cytochrome reveals a c-type haem, with no evidence of haem a, haem b or sirohaem. The cytochrome has an M(r) of 89000 as determined by denaturing PAGE, and has an isoelectric point of 5.2 as determined by analytical isoelectric focusing. Dithionite-reduced cytochrome can donate electrons to Fe(III)-nitrilotriacetic acid and synthetic ferrihydrite, thus demonstrating that the cytochrome has redox and thermodynamic properties required for reduction of Fe(III). Analysis using cyclic voltammetry confirmed that the reduced cytochrome can catalytically transfer electrons to ferrihydrite, further demonstrating its ability to be an electron transport mediator in anaerobic Fe(III) respiration. Sequence analysis of a cloned chromosomal DNA fragment revealed a 2307 bp open reading frame (ferA) encoding a 768 amino acid protein corresponding to the 89 kDa cytochrome. The deduced amino acid sequence (FerA) translated from the open reading frame contained 12 putative haem-binding motifs, as well as a hydrophobic N-terminal membrane anchor sequence, a lipid-attachment site and an ATP/GTP-binding site. FerA displayed 20% or less identity with amino acid sequences of other known cytochromes, although it does share some features with characterized polyhaem cytochromes c.
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Affiliation(s)
- T S Magnuson
- Department of Microbiology, P.O. Box 3520, Montana State University, Bozeman, MT 59717-3520, USA
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