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Gregory A, Wright D, Spencer H, Mankowski JJ, Dickens JC, Stephens J, Neuber AA. An apparatus for probing multipactor in X-band waveguide components. Rev Sci Instrum 2023; 94:2888169. [PMID: 37140338 DOI: 10.1063/5.0139620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 04/18/2023] [Indexed: 05/05/2023]
Abstract
Rectangular waveguides are susceptible to avalanche-style breakdown via the multipactor phenomenon. The growth in secondary electron density produced via multipactor can damage and destroy RF components. A pulse-adjustable, hard-switched modulator powering an X-band magnetron was utilized to drive a modular experimental setup that enables testing different surface geometries and coatings. Power measurements, taken via diodes, and phase measurements, facilitated via a double-balanced mixer, were integrated into the overall apparatus enabling multipactor detection with high sensitivity and nanosecond temporal resolution. The utilized 150 kW peak microwave source with 2.5 μs pulse width and 100 Hz repetition frequency allows for threshold testing without the need for initial electron seeding. This paper includes the initial results of surface conditioning of the test multipactor gap via electron bombardment.
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Affiliation(s)
- A Gregory
- Center for Pulsed Power and Power Electronics, Texas Tech University, Lubbock, Texas 79409, USA
| | - D Wright
- Center for Pulsed Power and Power Electronics, Texas Tech University, Lubbock, Texas 79409, USA
| | - H Spencer
- Center for Pulsed Power and Power Electronics, Texas Tech University, Lubbock, Texas 79409, USA
| | - J J Mankowski
- Center for Pulsed Power and Power Electronics, Texas Tech University, Lubbock, Texas 79409, USA
| | - J C Dickens
- Center for Pulsed Power and Power Electronics, Texas Tech University, Lubbock, Texas 79409, USA
| | - J Stephens
- Center for Pulsed Power and Power Electronics, Texas Tech University, Lubbock, Texas 79409, USA
| | - A A Neuber
- Center for Pulsed Power and Power Electronics, Texas Tech University, Lubbock, Texas 79409, USA
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Pokhrel S, Gregory A, Mellor A. Perioperative care in cardiac surgery. BJA Educ 2021; 21:396-402. [PMID: 34567795 PMCID: PMC8446225 DOI: 10.1016/j.bjae.2021.05.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/17/2021] [Indexed: 10/20/2022] Open
Affiliation(s)
- S. Pokhrel
- James Cook University Hospital, Middlesbrough, UK
| | | | - A. Mellor
- James Cook University Hospital, Middlesbrough, UK
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Sayer J, Stirland H, Gregory A, Peck M, Deakin M, Lee K. Type 2 and 3 intestinal failure workload at a district general hospital - implications for national commissioning. Clin Nutr ESPEN 2018. [DOI: 10.1016/j.clnesp.2018.09.070] [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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Gregory A, Sunil K. 334 The sun and your health: Targeting teenagers and adolescents in British Columbia. J Invest Dermatol 2018. [DOI: 10.1016/j.jid.2018.03.340] [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: 11/26/2022]
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Lee JH, Gregory A, Hogarth P, Rogers C, Hayflick SJ. Looking Deep into the Eye-of-the-Tiger in Pantothenate Kinase-Associated Neurodegeneration. AJNR Am J Neuroradiol 2018; 39:583-588. [PMID: 29371252 DOI: 10.3174/ajnr.a5514] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2017] [Accepted: 10/31/2017] [Indexed: 01/17/2023]
Abstract
BACKGROUND AND PURPOSE A detailed delineation of the MR imaging changes in the globus pallidus in pantothenate kinase-associated neurodegeneration will be helpful for diagnosis and monitoring of patients. The aim of this study was to determine the morphologic spectrum of the "eye-of-the-tiger" sign and the topographic pattern of iron deposition in a group of patients with pantothenate kinase-associated neurodegeneration. MATERIALS AND METHODS Seventy-four MR imaging scans from 54 individuals with PANK2 mutations were analyzed for signal patterns in the globus pallidus. Sixteen SWI data from 15 patients who underwent 1.5T (n = 7), 3T (n = 7), and 7T (n = 2) MR imaging were included to visualize the iron topography. RESULTS The linear hyperintensity alongside the medial border of the globus pallidus was the earliest T2 signal change. This finding was evident before SWI changes from iron deposition became visible. T2WI performed in early childhood mostly showed isolated hyperintense signal. In adult patients, marked signal reduction within an earlier hyperintense center resulting from iron accumulation led to the loss of signal difference between the central and surrounding areas. Signal hypointensity on SWI progressed from the medial to the lateral portion of the globus pallidus with increasing age. The fiber connections between the medial globus pallidus and the anteromedial aspect of the substantia nigra and subthalamic nucleus were markedly hypointense on SWI. CONCLUSIONS In pantothenate kinase-associated neurodegeneration, the globus pallidus MR imaging changes using SWI develop as region-specific and age-dependent phenomena. Signal inhomogeneity was observed across the globus pallidus in pantothenate kinase-associated neurodegeneration and should be considered when determining the concentration of iron.
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Affiliation(s)
- J-H Lee
- From the Departments of Molecular and Medical Genetics (J.-H.L., A.G., P.H., C.R., S.J.H.) .,Department of Neurology (J.-H.L.), Pusan National University Yangsan Hospital, Medical Research Institute, Pusan National University School of Medicine, Yangsan, South Korea
| | - A Gregory
- From the Departments of Molecular and Medical Genetics (J.-H.L., A.G., P.H., C.R., S.J.H.)
| | - P Hogarth
- From the Departments of Molecular and Medical Genetics (J.-H.L., A.G., P.H., C.R., S.J.H.).,Neurology (P.H., S.J.H.)
| | - C Rogers
- From the Departments of Molecular and Medical Genetics (J.-H.L., A.G., P.H., C.R., S.J.H.)
| | - S J Hayflick
- From the Departments of Molecular and Medical Genetics (J.-H.L., A.G., P.H., C.R., S.J.H.) .,Neurology (P.H., S.J.H.).,Pediatrics (S.J.H.), Oregon Health & Science University, Portland, Oregon
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Fichadiya A, Kotha V, Gregory A, Herget E, Tai E, Holloway D, Appoo J. WHAT IS THE LONG-TERM AORTIC REMODELING OUTCOME AFTER HEMI-ARCH REPAIR FOR ACUTE TYPE A DISSECTION? AN 11-YEAR STUDY. Can J Cardiol 2017. [DOI: 10.1016/j.cjca.2017.07.079] [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: 11/15/2022] Open
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Miller R, Gregory A, Kent W, Clarke B. RISK OF PERI-OPERATIVE BLEEDING AND OUTCOMES DURING LEFT VENTRICULAR ASSIST DEVICE IMPLANTATION. Can J Cardiol 2017. [DOI: 10.1016/j.cjca.2017.07.306] [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: 10/18/2022] Open
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Abstract
In the My Teaching Partner (MTP) program, coaches engage teachers in six to nine coaching cycles across a school year. Guided by the program's theory, coaches help teachers reflect on the emotional, organizational, and instructional features of classrooms. MTP was originally developed for Pre-K and early elementary classrooms (MTP Pre-K), but the current paper focuses on the secondary school version of this program, MTP-Secondary (MTP-S), given the need for coaching models with middle and high school teachers. The paper presents the guiding theory of MTP-S and how it relates to key components of the coaching cycle. We then offer a brief synthesis of research demonstrating its effectiveness in raising achievement, promoting positive peer interactions, and reducing racial disparities in teachers' discipline practices. We provide ideas for future research that would help advance theory on the essential components of effective coaching programs in secondary schools.
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Affiliation(s)
- A Gregory
- Rutgers The State University of New Jersey, 152 Frelinghuysen Road, Piscataway, NJ
| | | | | | | | - J P Allen
- Department of Psychology, University of Virginia
| | - R C Pianta
- Curry School of Education, University of Virginia
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Gregory A, Vedio A, Stone B, Green S, Bronsdon C. Targeted testing in primary care demonstrates high prevalence of hepatitis B infection within the Slovak-Roma population in Sheffield, UK. J Viral Hepat 2014; 21:e138-9. [PMID: 25056611 DOI: 10.1111/jvh.12287] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- A Gregory
- Page Hall Medical Centre, Sheffield, UK.
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Gregory A, Hutcheon D. Substituting Peanut Flour for Wheat Flour in a Muffin Recipe to Increase Protein Intake. J Acad Nutr Diet 2012. [DOI: 10.1016/j.jand.2012.06.161] [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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Kilburn R, Gregory A, Murray A. Using a Markov-Chain Monte-Carlo modelling approach to identify the relative risk to farmed Scottish Rainbow trout (Oncorhynchus mykiss) in a multi-sector industry of Viral Haemorrhagic Septicaemia Viruses from introduction and emergent sources. Ecol Modell 2012. [DOI: 10.1016/j.ecolmodel.2012.04.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [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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Kruer MC, Boddaert N, Schneider SA, Houlden H, Bhatia KP, Gregory A, Anderson JC, Rooney WD, Hogarth P, Hayflick SJ. Neuroimaging features of neurodegeneration with brain iron accumulation. AJNR Am J Neuroradiol 2011; 33:407-14. [PMID: 21920862 DOI: 10.3174/ajnr.a2677] [Citation(s) in RCA: 161] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
NBIA characterizes a class of neurodegenerative diseases that feature a prominent extrapyramidal movement disorder, intellectual deterioration, and a characteristic deposition of iron in the basal ganglia. The diagnosis of NBIA is made on the basis of the combination of representative clinical features along with MR imaging evidence of iron accumulation. In many cases, confirmatory molecular genetic testing is now available as well. A number of new subtypes of NBIA have recently been described, with distinct neuroradiologic and clinical features. This article outlines the known subtypes of NBIA, delineates their clinical and radiographic features, and suggests an algorithm for evaluation.
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Affiliation(s)
- M C Kruer
- Department of Pediatrics, Sanford Children's Research Center, University of South Dakota Sanford College of Medicine, Sioux Falls, South Dakota 57104, USA.
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Affiliation(s)
- L A Munro
- Marine Scotland, Marine Laboratory, Aberdeen, UK
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Gregory A, Munro LA, Snow M, Urquhart KL, Murray AG, Raynard RS. An experimental investigation on aspects of infectious salmon anaemia virus (ISAV) infection dynamics in seawater Atlantic salmon, Salmo salar L. J Fish Dis 2009; 32:481-489. [PMID: 19538641 DOI: 10.1111/j.1365-2761.2009.00999.x] [Citation(s) in RCA: 6] [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] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
This study investigated infection dynamics of infectious salmon anaemia virus (ISAV) by conducting two experiments to examine minimum infective dose and viral shedding of ISAV. In terms of minimum infective dose, the high variability between replicate tanks and the relatively slow spread of infection through the population at 1 x 10(1) TCID(50) mL(-1) indicated this dose is approaching the minimum infective dose for ISAV in seawater salmon populations. A novel qPCR assay incorporating an influenza virus control standard with each seawater sample was developed that enabled the quantity of ISAV shed from infected populations to be estimated in values equivalent to viral titres. Viral shedding was first detected at 7 days post-challenge (5.8 x 10(-2) TCID(50) mL(-1)kg(-1)) and rose to levels above the minimum infective dose (4.2 x 10(1) TCID(50) mL(-1)kg(-1)) on day 11 post-challenge, 2 days before mortalities in ISAV inoculated fish started. These results clearly demonstrate that a large viral shedding event occurs before death. Viral titres peaked at 7.0 x 10(1) TCID(50) mL(-1)kg(-1) 15 days post-infection. These data provide important information relevant to the management of ISA.
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Affiliation(s)
- A Gregory
- Fisheries Research Services, Aberdeen, UK
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Gregory A, Hurley B, Tran H, Valentine A, She YM, Knowles V, Plaxton W. In vivo regulatory phosphorylation of the phosphoenolpyruvate carboxylase AtPPC1 in phosphate-starved Arabidopsis thaliana. Biochem J 2009; 420:57-65. [PMID: 19228119 PMCID: PMC2677216 DOI: 10.1042/bj20082397] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2008] [Revised: 02/10/2009] [Accepted: 02/19/2009] [Indexed: 11/17/2022]
Abstract
PEPC [PEP(phosphoenolpyruvate) carboxylase] is a tightly controlled cytosolic enzyme situated at a major branchpoint in plant metabolism. Accumulating evidence indicates important functions for PEPC and PPCK (PEPC kinase) in plant acclimation to nutritional P(i) deprivation. However, little is known about the genetic origin or phosphorylation status of native PEPCs from -P(i) (P(i)-deficient) plants. The transfer of Arabidopsis suspension cells or seedlings to -P(i) growth media resulted in: (i) the marked transcriptional upregulation of genes encoding the PEPC isoenzyme AtPPC1 (Arabidopsis thaliana PEPC1), and PPCK isoenzymes AtPPCK1 and AtPPCK2; (ii) >2-fold increases in PEPC specific activity and in the amount of an immunoreactive 107-kDa PEPC polypeptide (p107); and (iii) In vivo p107 phosphorylation as revealed by immunoblotting of clarified extracts with phosphosite-specific antibodies to Ser-11 (which could be reversed following P(i) resupply). Approx. 1.3 mg of PEPC was purified 660-fold from -P(i) suspension cells to apparent homogeneity with a specific activity of 22.3 units x mg(-1) of protein. Gel filtration, SDS/PAGE and immunoblotting demonstrated that purified PEPC exists as a 440-kDa homotetramer composed of identical p107 subunits. Sequencing of p107 tryptic and Asp-N peptides by tandem MS established that this PEPC is encoded by AtPPC1. P(i)-affinity PAGE coupled with immunoblotting indicated stoichiometric phosphorylation of the p107 subunits of AtPPC1 at its conserved Ser-11 phosphorylation site. Phosphorylation activated AtPPC1 at pH 7.3 by lowering its Km(PEP) and its sensitivity to inhibition by L-malate and L-aspartate, while enhancing activation by glucose 6-phosphate. Our results indicate that the simultaneous induction and In vivo phosphorylation activation of AtPPC1 contribute to the metabolic adaptations of -P(i) Arabidopsis.
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Key Words
- arabidopsis
- gene expression
- pi starvation
- mass spectrometry
- phosphoenolpyruvate carboxylase kinase (ppck)
- protein phosphorylation
- ab, antibody
- anti-rcpepc igg, anti-(ricinus communis pepc) igg
- atppc1, arabidopsis thaliana pepc1
- cam, crassulacean acid metabolism
- dtt, dithiothreitol
- glc-6-p, glucose 6-phosphate
- maldi, matrix-assisted laser-desorption ionization
- ms medium, murashige and skoog medium
- ms/ms, tandem ms
- p107, 107-kda pepc polypeptide
- omaldi 2, orthogonal maldi 2
- pep, phosphoenolpyruvate
- pepc, pep carboxylase
- +pi, pi-sufficient
- −pi, pi-deficient
- pp2a, protein phosphatase type-2a
- ppck, pepc kinase
- q-tof, quadrupole time-of-flight
- qqtof, quadrupole/quadrupole tof
- rt, reverse transcription
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Affiliation(s)
- Allison L. Gregory
- *Department of Biochemistry, Queen's University, Kingston, ON, Canada, K7L 3N6
| | - Brenden A. Hurley
- †Department of Biology, Queen's University, Kingston, ON, Canada, K7L 3N6, ‡Plant Metabolomics Group
| | - Hue T. Tran
- †Department of Biology, Queen's University, Kingston, ON, Canada, K7L 3N6, ‡Plant Metabolomics Group
| | - Alexander J. Valentine
- Department of Biotechnology, Faculty of Science, University of the Western Cape, Bellville 7535, South Africa
| | - Yi-Min She
- §Department of Chemistry, Queen's University, Kingston, ON, Canada, K7L 3N6
| | - Vicki L. Knowles
- †Department of Biology, Queen's University, Kingston, ON, Canada, K7L 3N6, ‡Plant Metabolomics Group
| | - William C. Plaxton
- *Department of Biochemistry, Queen's University, Kingston, ON, Canada, K7L 3N6
- †Department of Biology, Queen's University, Kingston, ON, Canada, K7L 3N6, ‡Plant Metabolomics Group
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Urquhart K, Murray AG, Gregory A, O'Dea M, Munro LA, Smail DA, Shanks AM, Raynard RS. Estimation of infectious dose and viral shedding rates for infectious pancreatic necrosis virus in Atlantic salmon, Salmo salar L., post-smolts. J Fish Dis 2008; 31:879-887. [PMID: 19017067 DOI: 10.1111/j.1365-2761.2008.00989.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Infectious dose and shedding rates are important parameters to estimate in order to understand the transmission of infectious pancreatic necrosis virus (IPNV). Bath challenge of Atlantic salmon post-smolts was selected as the route of experimental infection as this mimics a major natural route of exposure to IPNV infection. Doses ranging from 10(2) to 10(-4) 50% end-point tissue culture infectious dose (TCID(50)) mL(-1) sea water were used to estimate the minimum infectious dose for a Scottish isolate of IPNV. The minimum dose required to induce infection in Atlantic salmon post-smolts was <10(-1) TCID(50) mL(-1) by bath immersion (4 h at 10 degrees C). The peak shedding rate for IPNV following intraperitoneal challenge using post-smolts was estimated to be 6.8 x 10(3) TCID(50) h(-1) kg(-1) and occurred 11 days post-challenge. This information may be incorporated into mathematical models to increase the understanding of the dispersal of IPNV from marine salmon sites.
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Affiliation(s)
- K Urquhart
- Fisheries Research Services Marine Laboratory, Aberdeen, UK.
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Abstract
Neurodegeneration with brain iron accumulation (NBIA) describes a group of progressive neurodegenerative disorders characterised by high brain iron and the presence of axonal spheroids, usually limited to the central nervous system. Mutations in the PANK2 gene account for the majority of NBIA cases and cause an autosomal recessive inborn error of coenzyme A metabolism called pantothenate kinase associated neurodegeneration (PKAN). More recently, it was found that mutations in the PLA2G6 gene cause both infantile neuroaxonal dystrophy (INAD) and, more rarely, an atypical neuroaxonal dystrophy that overlaps clinically with other forms of NBIA. High brain iron is also present in a portion of these cases. Clinical assessment, neuroimaging, and molecular genetic testing all play a role in guiding the diagnostic evaluation and treatment of NBIA.
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Affiliation(s)
- A Gregory
- Molecular and Medical Genetics, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA.
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Gregory A, Westaway SK, Holm IE, Kotzbauer PT, Hogarth P, Sonek S, Coryell JC, Nguyen TM, Nardocci N, Zorzi G, Rodriguez D, Desguerre I, Bertini E, Simonati A, Levinson B, Dias C, Barbot C, Carrilho I, Santos M, Malik I, Gitschier J, Hayflick SJ. Neurodegeneration associated with genetic defects in phospholipase A(2). Neurology 2008; 71:1402-9. [PMID: 18799783 DOI: 10.1212/01.wnl.0000327094.67726.28] [Citation(s) in RCA: 205] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE Mutations in the gene encoding phospholipase A(2) group VI (PLA2G6) are associated with two childhood neurologic disorders: infantile neuroaxonal dystrophy (INAD) and idiopathic neurodegeneration with brain iron accumulation (NBIA). INAD is a severe progressive psychomotor disorder in which axonal spheroids are found in brain, spinal cord, and peripheral nerves. High globus pallidus iron is an inconsistent feature of INAD; however, it is a diagnostic criterion of NBIA, which describes a clinically and genetically heterogeneous group of disorders that share this hallmark feature. We sought to delineate the clinical, radiographic, pathologic, and genetic features of disease resulting from defective phospholipase A(2). METHODS We identified 56 patients clinically diagnosed with INAD and 23 with idiopathic NBIA and screened their DNA for PLA2G6 mutations. RESULTS Eighty percent of patients with INAD had mutations in PLA2G6, whereas mutations were found in only 20% of those with idiopathic NBIA. All patients with two null mutations had a more severe phenotype. On MRI, nearly all mutation-positive patients had cerebellar atrophy, and half showed brain iron accumulation. We observed Lewy bodies and neurofibrillary tangles in association with PLA2G6 mutations. CONCLUSION Defects in phospholipase A(2) lead to a range of phenotypes. PLA2G6 mutations are associated with nearly all cases of classic infantile neuroaxonal dystrophy but a minority of cases of idiopathic neurodegeneration with brain iron accumulation, and genotype correlates with phenotype. Cerebellar atrophy predicts which patients are likely to be mutation-positive. The neuropathologic changes that are caused by defective phospholipase A(2) suggest a shared pathogenesis with both Parkinson and Alzheimer diseases.
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Affiliation(s)
- A Gregory
- Department of Molecular and Medical Genetics, Oregon Health & Science University, L103a, 3181 SW Sam Jackson Park Rd., Portland, OR 97239-3098, USA
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McNeill A, Birchall D, Hayflick SJ, Gregory A, Schenk JF, Zimmerman EA, Shang H, Miyajima H, Chinnery PF. T2* and FSE MRI distinguishes four subtypes of neurodegeneration with brain iron accumulation. Neurology 2008; 70:1614-9. [PMID: 18443312 DOI: 10.1212/01.wnl.0000310985.40011.d6] [Citation(s) in RCA: 197] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Neurodegeneration with brain iron accumulation (NBIA) defines a group of genetic disorders characterized by brain iron deposition and associated with neuronal death. The known causes of NBIA include pantothenate kinase-associated neurodegeneration (PKAN), neuroferritinopathy, infantile neuroaxonal dystrophy (INAD), and aceruloplasminemia. OBJECTIVE To define the radiologic features of each NBIA subtype. METHODS Brain MRIs from patients with molecularly confirmed PKAN (26 cases), neuroferritinopathy (21 cases), INAD (four cases), and aceruloplasminemia (10 cases) were analyzed blindly to delineate patterns of iron deposition and neurodegeneration. RESULTS In most cases of PKAN, abnormalities were restricted to globus pallidus and substantia nigra, with 100% having an eye of the tiger sign. In a minority of PKAN cases there was hypointensity of the dentate nuclei (1/5 on T2* sequences, 2/26 on fast spin echo [FSE]). In INAD, globus pallidus and substantia nigra were involved on T2* and FSE scans, with dentate involvement only seen on T2*. By contrast, neuroferritinopathy had consistent involvement of the dentate nuclei, globus pallidus, and putamen, with confluent areas of hyperintensity due to probable cavitation, involving the pallida and putamen in 52%, and a subset having lesions in caudate nuclei and thalami. More uniform involvement of all basal ganglia and the thalami was typical in aceruloplasminemia, but without cavitation. CONCLUSIONS In the majority of cases, different subtypes of neurodegeneration associated with brain iron accumulation can be reliably distinguished with T2* and T2 fast spin echo brain MRI, leading to accurate clinical and subsequent molecular diagnosis.
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Affiliation(s)
- A McNeill
- Department of Neurology, Regional Neurosciences Centre, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
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Wallace IS, Gregory A, Murray AG, Munro ES, Raynard RS. Distribution of infectious pancreatic necrosis virus (IPNV) in wild marine fish from Scottish waters with respect to clinically infected aquaculture sites producing Atlantic salmon, Salmo salar L. J Fish Dis 2008; 31:177-186. [PMID: 18261031 DOI: 10.1111/j.1365-2761.2007.00886.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
This study represents the first large-scale investigation of IPNV in Scottish wild marine fish. Kidney samples were taken from 30 627 fish comprising 37 species and 45 isolations were made from nine different species, illustrating these as reservoirs of IPNV in Scottish waters. The estimated prevalence of IPNV in the Scottish marine environment was low at 0.15% (90% confidence intervals, (CI) of 0.11-0.19%). This was significantly greater in fish caught less than 5.0 km from IPN-positive fish farms in Shetland, at 0.58% (90% CI of 0.45-0.77%). This prevalence persisted and did not significantly decrease over the 16-month period of study. The estimated prevalence of IPNV for each positive species was less than 1% with the statistically non-significant exceptions of flounder, Platichthys flesus (L.), at 12.5% (90% CI of 0.64-47.06%) and saithe, Pollachius virens (L.), at 1.11% (90% CI of 0.49-2.19%). The 45 isolates were titrated and all but two were below the detection limit of the test (<55 PFU g(-1)). Titres of 3.8 x 10(2) PFU g(-1) and 2.8 x 10(1) PFU g(-1) were calculated from common dab, Limanda limanda (L.), and saithe, respectively. This study provides evidence that clinical outbreaks of IPN in farmed Atlantic salmon may cause a localized small increase in the prevalence of IPNV in wild marine fish.
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Affiliation(s)
- I S Wallace
- Marine Laboratory, Fisheries Research Services, 374 Victoria Road, Aberdeen, UK
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Abstract
Infectious pancreatic necrosis (IPN) is a highly contagious disease of young salmonid fish, and is one of the most serious economic diseases in aquaculture. In Scotland, an increase in IPN virus (IPNV) outbreaks in seawater Atlantic salmon, Salmo salar, has been reported in recent years. The aim of this study was to analyse the VP2 gene from recent IPNV isolates from Scotland, to determine whether there are epidemiological links between IPNV isolates from farms (13), wild fish (17) and the environment (6) in order to investigate potential wild and farmed fish interactions. Comparison of the nucleotide sequence of the VP2 gene revealed that 34 of 36 isolates were 97.1-100% similar and the deduced amino acid sequences showed 97-100% identity. Two isolates from wild fish exhibited the most divergence at 85-87.3% similarity to the other isolates at the nucleotide level and 88.2-90.8% identity at the deduced amino acid level. Phylogenetic analyses revealed that 34 of 36 of the isolates from Scotland were genetically closely related to the A2 (Sp) serotype of IPNV. The two wild isolates from seatrout, Salmo trutta, and flounder, Platichthys flesus, were most closely related to the European A5 (Te) serotype. This study represents a comprehensive IPNV phylogenetic study that indicates that there are closely related or identical isolates in circulation in the marine environment, which adds evidence that disease interactions between wild and farmed fish may occur. This type of analysis is a useful tool in the management and control of fish diseases because it can assist in the identification of epidemiological links and highlight potential risks to aquaculture.
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Affiliation(s)
- N Bain
- FRS Marine Laboratory, Aberdeen, UK.
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Gregory A, Munro LA, Wallace IS, Bain N, Raynard RS. Detection of infectious pancreatic necrosis virus (IPNV) from the environment in the vicinity of IPNV-infected Atlantic salmon farms in Scotland. J Fish Dis 2007; 30:621-30. [PMID: 17850578 DOI: 10.1111/j.1365-2761.2007.00844.x] [Citation(s) in RCA: 6] [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] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Infectious pancreatic necrosis virus (IPNV) has been isolated from mussels, sediment and surface water in the vicinity of clinically infected salmon farms, at shore bases supplying the farms and for several hundred metres distance from farms in the direction of current flow. There was evidence of decreasing prevalence of IPNV in mussels from Shetland once IPN outbreaks subsided, indicating they are an unlikely source of re-infection on farms. There was little evidence of persistence in the environment, although conclusions were complicated by the presence of IPNV on neighbouring farms 1 year after the outbreak.
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Affiliation(s)
- A Gregory
- FRS Marine Laboratory, Victoria Road, Aberdeen, UK.
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Morgan SS, Bonshahi A, Pradhan N, Gregory A, Gambhir A, Porter ML. The influence of postoperative coronal alignment on revision surgery in total knee arthroplasty. Int Orthop 2007; 32:639-42. [PMID: 17611758 PMCID: PMC2551715 DOI: 10.1007/s00264-007-0391-0] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2007] [Accepted: 04/28/2007] [Indexed: 12/01/2022]
Abstract
This study examines the association between postoperative coronal tibiofemoral alignment and revision surgery in knee arthroplasty. We retrospectively reviewed the case notes and post-operative long-leg radiographs of 197 Kinemax knee arthroplasty with mean follow-up of 9 years (SD 2.2). They were divided into three groups: neutral, valgus and varus. Revision or decision to revise was used as a hard endpoint. There was no statistical difference among the three groups (p=0.78). We conclude that aseptic failure of a total knee is multifactorial. Coronal tibio-femoral alignment may not be as important a cause of failure as has been previously thought.
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Freeman K, Gregory A, Turner A, Blasco P, Hogarth P, Hayflick S. Intellectual and adaptive behaviour functioning in pantothenate kinase-associated neurodegeneration. J Intellect Disabil Res 2007; 51:417-26. [PMID: 17493025 PMCID: PMC2099459 DOI: 10.1111/j.1365-2788.2006.00889.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
BACKGROUND Pantothenate kinase-associated neurodegeneration (PKAN), an extremely rare autosomal recessive disorder resulting in iron accumulation in the brain, has a diverse phenotypic expression. Based on limited case studies of one or two patients, intellectual impairment is considered part of PKAN. Investigations of cognitive functioning have utilized specific neuropsychological tests, without attention to general intellectual skills or adaptive behaviour. METHODS Sixteen individuals with PKAN completed measures of global intellectual functioning, and participants or care providers completed measures of adaptive behaviour skills and day-to-day functional limitations. Clinicians provided global ratings of condition severity. RESULTS Testing with standardized measures documented varied phenotypic expression, with general cognitive skills and adaptive behaviour ranging from high average to well below average. Age of disease onset correlated with measures of intellectual functioning, adaptive functioning and disease severity. CONCLUSIONS Findings support previously described clinical impressions of varied cognitive impairment and the association between age of onset and impairment. Further, they add important information regarding the natural history of the disease and suggest assessment strategies for use in treatment trials.
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Affiliation(s)
- K Freeman
- Child Development and Rehabilitation Center, Portland, OR, USA.
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O'Dowd H, Gladwell P, Rogers CA, Hollinghurst S, Gregory A. Cognitive behavioural therapy in chronic fatigue syndrome: a randomised controlled trial of an outpatient group programme. Health Technol Assess 2007; 10:iii-iv, ix-x, 1-121. [PMID: 17014748 DOI: 10.3310/hta10370] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [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] [Indexed: 11/22/2022] Open
Abstract
OBJECTIVES To test the hypothesis that group cognitive behavioural therapy (CBT) will produce an effective and cost-effective management strategy for patients in primary care with chronic fatigue syndrome/myalgic encephalopathy (CFS/ME). DESIGN A double-blind, randomised controlled trial was adopted with three arms. Outcomes were assessed at baseline and 6 and 12 months after first assessment and results were analysed on an intention-to-treat basis. SETTING A health psychology department for the management of chronic illness in a general hospital in Bristol, UK. PARTICIPANTS Adults with a diagnosis of CFS/ME referred by their GP. INTERVENTIONS The three interventions were group CBT incorporating graded activity scheduling, education and support group (EAS) and standard medical care (SMC). OUTCOME MEASURES The primary outcome measure was the Short Form with 36 Items (SF-36) physical and mental health summary scales. Other outcome measures included the Chalder fatigue scale, Hospital Anxiety and Depression Scale, General Health Questionnaire, physical function (shuttles walked, walking speed and perceived fatigue), health utilities index and cognitive function (mood, recall and reaction times). RESULTS A total of 153 patients were recruited to the trial and 52 were randomised to receive CBT, 50 to EAS and 51 to SMC. Twelve patients failed to attend for the 12-month follow-up and 19 patients attended one follow-up, but not both. The sample was found to be representative of the patient group and the characteristics of the three groups were similar at baseline. Three outcome measures, SF-36 mental health score, Chalder fatigue scale and walking speed, showed statistically significant differences between the groups. Patients in the CBT group had significantly higher mental health scores [difference +4.35, 95% confidence interval (CI) +0.72 to +7.97, p = 0.019], less fatigue (difference -2.61, 95% CI -4.92 to -0.30, p = 0.027) and were able to walk faster (difference +2.83 shuttles, 95% CI +1.12 to +5.53, p = 0.0013) than patients in the SMC group. CBT patients also walked faster and were less fatigued than those randomised to EAS (walking speed: difference +1.77, 95% CI +0.025 to +3.51, p = 0.047; fatigue: difference -3.16, 95% CI -5.59 to -0.74, p = 0.011). Overall, no other statistically significant difference across the groups was found, although for many measures a trend towards an improved outcome with CBT was seen. Except for walking speed, which, on average, increased by +0.87 shuttles (95% CI +0.09 to +1.65, p = 0.029) between the 6- and 12-month follow-ups, the scores were similar at 6 and 12 months. At baseline, 30% of patients had an SF-36 physical score within the normal range and 52% had an SF-36 mental health score in the normal range. At 12 months, the physical score was in the normal range for 46% of the CBT group, 26% of the EAS group and 44% of SMC patients. For mental health score the percentages were CBT 74%, EAS 67% and SMC 70%. Of the CBT group, 32% showed at least a 15% increase in physical function and 64% achieved a similar improvement in their mental health. For the EAS and SMC groups, this improvement in physical and mental health was achieved for 40 and 60% (EAS) and 49 and 53% (SMC), respectively. The cost-effectiveness of the intervention proved very difficult to assess and did not yield reliable conclusions. CONCLUSIONS Group CBT did not achieve the expected change in the primary outcome measure as a significant number did not achieve scores within the normal range post-intervention. The treatment did not return a significant number of subjects to within the normal range on this domain; however, significant improvements were evident in some areas. Group CBT was effective in treating symptoms of fatigue, mood and physical fitness in CFS/ME. It was found to be as effective as trials using individual therapy in these domains. However, it did not bring about improvement in cognitive function or quality of life. There was also evidence of improvement in the EAS group, which indicates that there is limited value in the non-specific effects of therapy. Further research is needed to develop better outcome measures, assessments of the broader costs of the illness and a clearer picture of the characteristics best fitted to this type of intervention.
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Affiliation(s)
- H O'Dowd
- Pain Management Centre, Frenchay Hospital, Bristol, UK
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Crewe HK, Ghobadi C, Gregory A, Rostami-Hodjegan A, Lennard MS. Determination by liquid chromatography-mass spectrometry of clomiphene isomers in the plasma of patients undergoing treatment for the induction of ovulation. J Chromatogr B Analyt Technol Biomed Life Sci 2006; 847:296-9. [PMID: 17085084 DOI: 10.1016/j.jchromb.2006.10.019] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2006] [Revised: 09/28/2006] [Accepted: 10/08/2006] [Indexed: 10/23/2022]
Abstract
A rapid, sensitive and selective LC-MS method is described for the simultaneous determination of zuclomiphene and enclomiphene in plasma from patients undergoing treatment with clomiphene citrate for the induction of ovulation. Samples spiked with N-didesmethyltamoxifen, the internal standard, were extracted into methyl tertiary butyl ether. The compounds were separated on a Luna C(18) analytical column, and a mobile phase of methanol-water (70:30 v/v) containing 0.05% trifluoroacetic acid at a flow rate of 1ml/min. The limits of determination were 35pg/ml and 7pg/ml for zu- and enclomiphene, respectively. Within-day coefficients of variation ranged from 2.1% to 7.2%.
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Affiliation(s)
- H K Crewe
- Academic Unit of Clinical Pharmacology, University of Sheffield, Royal Hallamshire Hospital, Sheffield, UK
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28
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Gregory A, Hayflick SJ. PANK2 mutation screening recommended to confirm diagnosis of pantothenate kinase-associated neurodegeneration. AJNR Am J Neuroradiol 2006; 27:951. [PMID: 16687521 PMCID: PMC7975753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
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Snow M, Raynard RS, Murray AG, Bruno DW, King JA, Grant R, Bricknell IR, Bain N, Gregory A. An evaluation of current diagnostic tests for the detection of infectious salmon anaemia virus (ISAV) following experimental water-borne infection of Atlantic salmon, Salmo salar L. J Fish Dis 2003; 26:135-145. [PMID: 12962223 DOI: 10.1046/j.1365-2761.2003.00444.x] [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] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Four commonly used diagnostic tests [reverse transcription polymerase chain reaction (RT-PCR), indirect fluorescent antibody test (IFAT), virus culture and light microscopy] were evaluated for their ability to detect infectious salmon anaemia virus (ISAV) or tissue pathology following experimental infection of Atlantic salmon. Fish were infected with ISAV by water-borne exposure which mimics the route of natural infection. Forty-five per cent of pre-clinical fish tested yielded positive results by RT-PCR for at least one of the organs tested (kidney, heart, gill, liver, blood). No significant difference was detected between organs in the number or time of first occurrence of positive result. Virus culture identified a total of 14% of pre-clinical fish as ISAV-infected. The presence of ISAV in heart tissue was particularly notable (13% of fish sampled) as was the inability to culture virus from spleen tissue. In the case of IFAT, 15% of fish sampled were positive, although tissue other than kidney proved unsuitable for use in this method. Only limited ISAV-specific pathology was detectable by histological examination of fish prior to the onset of clinical disease. These findings reveal important information regarding the optimal choice of both tissue sample and diagnostic test for the routine diagnosis of ISAV.
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Affiliation(s)
- M Snow
- FRS Marine Laboratory, Aberdeen, UK
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30
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Shiran MR, Gregory A, Rostami-Hodjegan A, Tucker GT, Lennard MS. Determination of midazolam and 1'-hydroxymidazolam by liquid chromatography-mass spectrometry in plasma of patients undergoing methadone maintenance treatment. J Chromatogr B Analyt Technol Biomed Life Sci 2003; 783:303-7. [PMID: 12450551 DOI: 10.1016/s1570-0232(02)00673-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
A rapid, sensitive and selective LC-MS method was developed for the simultaneous determination of midazolam (MDZ) and 1'-hydroxymidazolam (1'-OHMDZ) in plasma taken from 54 patients undergoing methadone maintenance therapy, most of whom were multidrug users. Samples spiked with prazepam, the internal standard, and were extracted into diethyl ether. Compounds were separated on a Phenomenex Luna C(18) column and a mobile phase of acetonitrile-ammonium acetate buffer (10 mM, pH 4.7) (52:48, v/v) at a flow-rate of 1 ml/min. The limit of detection was 0.65 and 0.68 (ng/ml) for MDZ and 1'-OHMDZ, respectively. Within-day relative standard deviations were less than 8%.
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Affiliation(s)
- M R Shiran
- Molecular Pharmacology and Pharmacogenetics, Division of Clinical Sciences, University of Sheffield, UK.
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31
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Abstract
An in situ hybridisation method was developed to detect infectious salmon anaemia virus (ISAV) in fixed tissues from Atlantic salmon Salmo salar L. Three DNA probes detected ISAV in heart, liver, kidney, spleen, caeca, and mid-gut from infected farmed Atlantic salmon obtained from a natural outbreak of ISA. The strongest signals were obtained using Probe S8, from Segment 8 of ISAV. Hybridisation was most prominent in the endothelial cells of heart tissue. The probes reacted specifically with ISAV; no hybridisation was evident in uninfected tissues from Atlantic salmon. Importantly, the probes did not cross react with the pathogens IHNV (haematopoietic necrosis virus), IPNV (infectious pancreatic necrosis virus), SPDV (salmon pancreas disease virus) and VHSV (viral haemorrhagic septicemia virus).
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Affiliation(s)
- A Gregory
- Fisheries Research Services Marine Laboratory, Aberdeen, Scotland, UK.
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Abstract
Following the outbreak of infectious salmon anaemia (ISA) at salmon farms in Scotland, UK, a survey was established to determine the extent of infection in wild fish. All fish tested were free from the clinical symptoms of ISA. Isolations of ISAV were made from 5 sea trout within areas where ISA affected salmon farms were located. Evidence for ISAV in other sea trout was provided by ISA RT-PCR diagnostic tests. Results from ISA RT-PCR tests reveal evidence for ISAV being present in salmon parr, adult salmon and juvenile brown trout in rivers distant from salmon farms and indicate that, at the time of the survey (1998-1999), ISAV may have been widely distributed. Nucleotide sequence analysis of segments 2 and 8 showed that for most sequences from wild fish there was 100% homology with ISAV isolated from clinically affected farmed fish although evidence is presented which indicates variability in ISAV sequences from wild fish. Modelling the RT-PCR findings indicates that ISAV among salmonid fish was spatially non-random. Brown trout, sea trout and salmon (adult and parr) show a pattern of occasionally large numbers of positive samples against a background of very low numbers.
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Affiliation(s)
- R S Raynard
- Fisheries Research Services Marine Laboratory, Aberdeen, Scotland, UK.
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Murphy J, Gregory A, Semrud-Clikeman M, Brauer M. Antisocial adolescents fail to modulate responses in the face of punishment. Arch Clin Neuropsychol 1999. [DOI: 10.1093/arclin/14.8.679b] [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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Abdul Manap R, Wright CE, Gregory A, Rostami-Hodjegan A, Meller ST, Kelm GR, Lennard MS, Tucker GT, Morice AH. The antitussive effect of dextromethorphan in relation to CYP2D6 activity. Br J Clin Pharmacol 1999; 48:382-7. [PMID: 10510150 PMCID: PMC2014340 DOI: 10.1046/j.1365-2125.1999.00029.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [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] [Indexed: 11/20/2022] Open
Abstract
AIMS To test the hypothesis that inhibition of cytochrome P450 2D6 (CYP2D6) by quinidine increases the antitussive effect of dextromethorphan (DEX) in an induced cough model. METHODS Twenty-two healthy extensive metaboliser phenotypes for CYP2D6 were studied according to a double-blind, randomised cross-over design after administration of: (1) Placebo antitussive preceded at 1 h by placebo inhibitor; (2) 30 mg oral DEX preceded at 1 h by placebo inhibitor (DEX30); (3) 60 mg oral DEX preceded at 1 h by placebo inhibitor (DEX60); (4) 30 mg oral DEX preceded at 1 h by 50 mg oral quinidine sulphate (QDEX30). Cough frequency following inhalation of 10% citric acid was measured at baseline and at intervals up to 12 h. Plasma concentrations of DEX and its metabolites were measured up to 96 h by h.p.l.c. RESULTS Inhibition of CYP2D6 by quinidine caused a significant increase in the mean ratio of DEX to dextrorphan (DEX:DOR) plasma AUC(96) (0.04 vs 1.81, P<0.001). The mean (+/-s.d.) decrements in cough frequency below baseline over 12 h (AUEC) were: 8% (11), 17% (14.5), 25% (16.2) and 25% (16.9) for placebo, DEX30, DEX60 and QDEX30 treatments, respectively. Statistically significant differences in antitussive effect were detected for the contrasts between DEX60/placebo (P<0.001; 95% CI of difference +80, +327) and QDEX30/placebo (P<0.001, +88, +336), but not for DEX30/placebo, DEX30/DEX60 or DEX30/QDEX30 (P=0.071, -7, +241; P=0.254, -37, +211; P=0.187, -29, +219, respectively). CONCLUSIONS A significant antitussive effect was demonstrated after 60 mg dextromethorphan and 30 mg dextromethorphan preceded by 50 mg quinidine using an induced cough model. However, although the study was powered to detect a 10% difference in cough response, the observed differences for other contrasts were less than 10%, such that it was possible only to imply a dose effect (30 vs 60 mg) in the antitussive activity of DEX and enhancement of this effect by CYP2D6 inhibition.
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Affiliation(s)
- R Abdul Manap
- Pulmonary Medicine, Division of Clinical Sciences, University of Sheffield, Northern General Hospital, Sheffield, S5 7AU, UK
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Gregory A, Doull I, Pearce N, Cheng S, Leadbitter P, Holgate S, Beasley R. The relationship between anthropometric measurements at birth: asthma and atopy in childhood. Clin Exp Allergy 1999; 29:330-3. [PMID: 10202339 DOI: 10.1046/j.1365-2222.1999.00485.x] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Recent studies have reported that a large head circumference at birth is associated with an increased risk of raised serum IgE in adult life, and asthma during childhood. OBJECTIVE To examine the relationship between head circumference and other anthropometric measurements at birth and asthma and indices of atopy in childhood. METHODS The presence of asthma and measures of atopic status (total serum IgE level and skin prick tests to common allergens) were assessed prospectively in offspring of families participating in a community-based genetic study in Southampton, UK. Measures of perinatal variables including birth weight, head circumference at birth, and gestational age were obtained from hospital records of 239 offspring aged 6-23 years. RESULTS Children with a head circumference of 37 cm or more at birth had a relative risk of an elevated serum total IgE (> 150 IU) of 3.2 (95% CI 1.0-10.4). There were no consistent relationships between head circumference at birth and either skin prick positivity or the development of clinical asthma. There was no significant association between other perinatal markers and measures of atopic status or clinical asthma. CONCLUSION The study has identified that a large head circumference at birth is associated with an increased risk of an elevated total serum IgE in childhood. The reasons for this association, and the lack of an association with asthma are unclear and will require further research.
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Affiliation(s)
- A Gregory
- The Immunopharmacology Group, University Medicine, Southampton General Hospital, Southampton, UK
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36
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Gregory A, Murphy J, Tucker D, Randall P. Head injury and the MMPI-2 : Scale scores form four distinct clusters. Arch Clin Neuropsychol 1999. [DOI: 10.1093/arclin/14.1.30a] [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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Leung M, Jotshi CK, Goswami DY, Shah DO, Gregory A. Measurements of Absorption Rates of HFC Single and Blended Refrigerants in POE Oils. ACTA ACUST UNITED AC 1998. [DOI: 10.1080/10789669.1998.10391396] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Sech SM, Montoya JD, Bernier PA, Barnboym E, Brown S, Gregory A, Roehrborn CG. The so-called "placebo effect" in benign prostatic hyperplasia treatment trials represents partially a conditional regression to the mean induced by censoring. Urology 1998; 51:242-50. [PMID: 9495705 DOI: 10.1016/s0090-4295(97)00609-2] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVES To study the variability of assessment instruments (symptom questionnaires and flow rate recordings) in healthy volunteers during repeat administration in short intervals. To study the effect of inclusion criteria-based censoring of patients during screening for benign prostatic hyperplasia (BPH) treatment trials on the outcome of subsequent tests. METHODS One hundred forty-five male volunteers without known prostatic diseases with a mean age of 52 years (range 23 to 83) were given the American Urological Association (AUA) Symptom Index (SI), BPH Impact Index (II). Quality of Life (QOL) score, and a flow rate recording twice 10 to 20 days apart without any healthcare intervention. Data were collected and analyzed after typical BPH trial criteria were applied to the first test, and patients who did not "qualify" were censored. RESULTS Good correlation exists between two closely spaced administrations of the AUA SI, BPH II, QOL score, and flow rate recordings in healthy male volunteers with correlation coefficients between 0.73 and 0.89. Censoring patients and excluding them from the analysis of the second test based on typical BPH trial criteria induces a regression to the mean phenomenon, which results in an artificial improvement in these outcome parameters. The magnitude of the improvement increases as the selection and censoring criteria tighten. The mean differences between the first and second test range from 1.4 to 1.7 mL/s for the peak flow rate, from -1.0 to -1.4 for the AUA SI, and from -0.4 to -0.8 for the BPH II. All these differences induced solely by censoring with resulting regression to the mean are statistically significant. CONCLUSIONS Censoring of patients based on inclusion and exclusion criteria is typical for BPH treatment trials. One of the under-recognized effects of censoring is a regression to the mean, which leads to an apparent improvement in the outcome parameters assessed. In both placebo or sham-controlled trials, as well as in clinical series without controls, one must keep this effect and its relative magnitude in mind, and interpret the data from such trials with appropriate caution.
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Affiliation(s)
- S M Sech
- Department of Urology, The University of Texas Southwestern Medical Center at Dallas, 75235-9110, USA
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Shiao S, Patist A, Free M, Chhabra V, Huibers P, Gregory A, Patel S, Shah D. The importance of sub-angstrom distances in mixed surfactant systems for technological processes. Colloids Surf A Physicochem Eng Asp 1997. [DOI: 10.1016/s0927-7757(96)03912-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Mauerhan DR, Campbell M, Miller JS, Mokris JG, Gregory A, Kiebzak GM. Intra-articular morphine and/or bupivacaine in the management of pain after total knee arthroplasty. J Arthroplasty 1997; 12:546-52. [PMID: 9268795 DOI: 10.1016/s0883-5403(97)90178-9] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.8] [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] Open
Abstract
The purpose of this study was to determine if intra-articular injection of morphine or bupivacaine significantly decreased postoperative pain as well as the use of intravenous narcotics for pain relief in patients undergoing total knee arthroplasty (TKA). In a prospective, double-blind, randomized fashion, 105 patients undergoing TKA were divided into the following 4 groups defined by the intra-articular injection they received: group 1 (n = 27) received saline solution, group 2 (n = 26) received morphine sulfate (5 mg), group 3 (n = 24) received bupivacaine (50 mg), and group 4 (n = 28) received a combination of morphine sulfate and bupivacaine. The injections were administered immediately after wound closure by the Hemovac drainage tubing that remained clamped for 45 minutes after surgery to allow for absorption. Before surgery and at 2, 4, 6, 24, and 48 hours after surgery, pain intensity was recorded using a visual analog scale. Postoperative supplemental intravenous morphine and/or meperidine was administered via a patient-controlled analgesia device, and 24-hour drug usage was tabulated. Results were suggestive of a modest short-term reduction in pain scores in the morphine and bupivacaine treatment groups compared with placebo (saline); however, results were statistically significant only at 4 hours because of the great variability in the pain score data. The total amount of postoperative pain medication used in the first 24 hours after surgery was not statistically significant between the 4 treatment groups. Thus, the results put into question the benefit of postoperative intra-articular administration of morphine or bupivacaine in patients undergoing TKA.
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Affiliation(s)
- D R Mauerhan
- Miller Orthopaedic Clinic, Charlotte, NC 28203, USA
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Roehrborn CG, Gregory A, McConnell JD, Sagalowsky AI, Wians FH. Comparison of three assays for total serum prostate-specific antigen and percentage of free prostate-specific antigen in predicting prostate histology. Urology 1996; 48:23-32. [PMID: 8973696 DOI: 10.1016/s0090-4295(96)00606-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [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: 02/03/2023]
Abstract
OBJECTIVES To determine the statistical performance of three different assays for prostate specific antigen (PSA) and the percentage of free PSA with respect to the differentiation of histologic benign prostatic hyperplasia (BPH) and prostate cancer in men who underwent surgical removal of prostate tissue. METHODS Serum of 86 men scheduled for prostate surgery (transurethral resection of the prostate [TURP], simple open prostatectomy, radical prostatectomy, cystoprostatectomy) was frozen and subjected to measurement in batches using three different assays for total PSA (Hybritech Tandem-E, Abbott IMx, Tosoh AIA-600) and free PSA by the Hybritech method after a single freeze-thaw cycle. The histologic diagnosis of the removed tissue (35 BPH and 51 cancer) was used as a "gold standard" for classification of disease status. Sensitivity, specificity, positive and negative predictive values, and diagnostic efficiency were calculated for the three total PSA assays and the free/total PSA ratios for the entire cohort and subsets. Receiver-operating characteristic (ROC) curve analysis was used to compare the performance of the assays and ratios. RESULTS Mean and median total PSA values differed slightly between the three assays for all patients, and for those with BPH and cancer, but this difference was not significant. Because of a considerable overlap, the differences between the mean PSA values for men with BPH and prostate cancer were not significant. At a cutpoint of 4.0 ng/mL, sensitivity with respect to the differentiation between BPH and prostate cancer was 68.6% for all three total PSA assays; the respective AUCs (0.613-0.625) were not significantly different. While the performance of the free/total PSA ratios was superior, the differences were only significant when subsets of patients were considered with a total PSA between 4 and 10 ng/mL or 4 and 15 ng/mL (AUCs 0.789-0.816). Likewise, sensitivity, specificity, and diagnostic efficiency was better in these subsets of patients. CONCLUSIONS In this study in which a "gold standard" based on histologic analysis of the entire (or large part of) the prostate gland was used to classify disease status, the three assays for total serum PSA (Hybritech Tandem-E, Abbott IMx, and Tosoh AIA-600) performed very similarly with identical sensitivities (at a cutpoint of 4.0 ng/mL) and comparable AUCs with respect to the differentiation of men with histologic BPH and prostate cancer. The ratios of free/total PSA calculated as free PSA by the Hybritech manual immunoradiometric assay (IRMA) method over all three total PSA assays, performed marginally better in the entire patient population. However, in the subsets of patients with a PSA of 4-10 ng/mL and 4-15 ng/mL, all three ratios performed significantly better than the three total PSA assays. The proper choice of a cutpoint for the ratio (15%, 17%, 19%, or 21%) depends on the desirability of maximizing either sensitivity or specificity while optimizing diagnostic efficiency.
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Affiliation(s)
- C G Roehrborn
- Department of Urology, University of Texas Southwestern Medical Center 75235-9110, USA
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Blank FS, Austin M, Bennett A, Doe S, Gregory A, Keyes M, Labrie L, Loughlin L, Sabourin D, Vezolla R. Decreasing "door to thrombolysis" time at one busy acute care hospital. J Emerg Nurs 1995; 21:202-7. [PMID: 7630052 DOI: 10.1016/s0099-1767(05)80152-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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Abstract
The spatial offence behaviour of 45 British serial rapists was examined in order to generate a predictive model, of use to criminal investigators. Two alternative hypotheses were explored. One predicted that rapists would commute into an area to carry out their offence. The second predicted that they would "maraud" out from a fixed location. Of the 45 offenders, 39 fitted the "maurader" hypothesis. However, the area covered by this model was an average of nearly 180 square miles. A second complementary theory, developed from facets of offenders' backgrounds, was therefore used to refine the predictions of distance travelled to and between offences. This enabled the size of the residential zone predicted from the marauder model to be reduced to a mean area of just over ten square miles. Tests of these models, combined into a small scale expert system, predicted the correct area for 82% of the cases. Suggestions for the further development of this expert system are discussed.
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Affiliation(s)
- D V Canter
- Centre for Investigative Psychology, University of Surrey, Guildford, United Kingdom
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Abstract
The study and monitoring of facial appearance is particularly important in the field of orthodontics and reconstructive maxillo-facial surgery. The introduction of new medical imaging techniques, such as X-ray computerized tomography (CT), has enabled surgery to be planned in three dimensions, compared with conventional methods using lateral and antero-posterior cephalographic images. Whilst it is possible to visualize bone and soft tissue structure the repeated use of CT scanning is undesirable because of the high doses of radiation involved. The research involves the development of a simple, low cost and non-invasive three-dimensional scanning method for facial surfaces. This is achieved using a technique known as structured light, using a standard commercial slide projector, CCD cameras and a framestore linked to a PC. The eventual aim is to provide clinicians a software assisted surgical procedure, by merging X-ray and skin data, allowing the manipulation of bone and soft tissue. This will give the facility to predict and monitor post-surgical appearance, detailing the effects of surgery benefiting both the clinician and patient. The research focuses on how the images are obtained using the scanning system and the subsequent image processing of data to give a realistic 3D image using a standard PC.
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Affiliation(s)
- A Gregory
- School of Electrical Engineering, University of Bath, Claverton Down, UK
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45
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Abstract
An antigen capture enzyme-linked immunosorbent assay (ELISA) has been developed that could identify Haemonchus contortus antigens in dilute suspensions of worm homogenates and in faeces from sheep naturally infected with moderate burdens of the parasite. The ELISA is based on a polyclonal (rabbit or sheep) antibody coated solid-phase that captures parasite antigen from a suspension of worms or faeces. The captured antigen is detected by a mouse monoclonal antibody (MAb E2) that is reactive with a cuticle surface antigen of H. contortus. Binding of MAb E2 was shown to be specific for H. contortus and the ELISA was able to detect this antigen in faeces of some infected sheep. Characterisation of the antigen reacting with MAb E2 indicates it to be a collagenase and protease resistant surface protein of H. contortus that under reducing conditions in SDS-polyacrylamide gel electrophoresis exists as polypeptides of molecular weight 122, 56 and 49 kDa.
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Affiliation(s)
- T M Ellis
- Animal Health Laboratories, Department of Agriculture, Baron-Hay Court, South Perth, Australia
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Tucker GT, Mather LE, Lennard MS, Gregory A. Plasma concentrations of the stereoisomers of prilocaine after administration of the racemate: implications for toxicity? Br J Anaesth 1990; 65:333-6. [PMID: 2223362 DOI: 10.1093/bja/65.3.333] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
A chiral high pressure liquid chromatography method was developed to measure the separate isomers of prilocaine in plasma after administration of the racemate. The concentrations of the isomers in six patients were similar (S(+)/R(-) = 1.06 (SD 0.06)) after brachial plexus block with 1.5% (RS)-prilocaine hydrochloride 35 ml, suggesting that a higher systemic safety margin may not be achieved by substituting racemic prilocaine by one of its isomers. Much higher plasma concentrations of the S(+)- than the R(-)-form after oral administration of 300 mg of the racemate (n = 4) indicated a large difference in intrinsic metabolic clearance of the isomers on first pass through gut, liver or both organs.
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Affiliation(s)
- G T Tucker
- Department of Medicine and Pharmacology, University of Sheffield, Royal Hallamshire Hospital
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Sarvetnick N, Shizuru J, Liggitt D, Martin L, McIntyre B, Gregory A, Parslow T, Stewart T. Loss of pancreatic islet tolerance induced by beta-cell expression of interferon-gamma. Nature 1990; 346:844-7. [PMID: 2118234 DOI: 10.1038/346844a0] [Citation(s) in RCA: 269] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Interferon-gamma (IFN-gamma) is produced during the response to infection and participates in immunostimulatory events. We have previously reported the induction of diabetes in transgenic mice (ins-IFN-gamma) in which the expression of the lymphokine IFN-gamma is directed by the insulin promoter. This diabetes is a result of the progressive destruction of pancreatic islets that occurs with the influx of inflammatory cells. Here we demonstrate that this islet cell loss is mediated by lymphocytes, that engrafted histocompatible islets are destroyed, and that lymphocytes from the transgenic mice are cytotoxic to normal islets in vitro. These results indicate that the pancreatic expression of IFN-gamma can result in a loss of tolerance to normal islets, consistent with its role as an inducer of costimulatory activity, which is essential for lymphocyte activation during an immune response.
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Affiliation(s)
- N Sarvetnick
- Department of Developmental Biology, Genentech, Inc., South San Francisco, California 94080
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Cousins DV, Francis BR, Gow BL, Collins DM, McGlashan CH, Gregory A, Mackenzie RM. Tuberculosis in captive seals: bacteriological studies on an isolate belonging to the Mycobacterium tuberculosis complex. Res Vet Sci 1990; 48:196-200. [PMID: 2110376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Culture of tuberculous lesions from six of 14 captive seals yielded an organism which, on the basis of biochemical and drug sensitivity tests, was identified as Mycobacterium bovis, although the organism showed a weak cording pattern and was glycerol tolerant. It was pathogenic in rabbits and guinea pigs and after passage the organism exhibited strong cord formation and was glycerol intolerant. Restriction endonuclease analysis and sodium dodecyl-sulphate polyacrylamide gel electrophoresis indicated that the organism belonged to the Mycobacterium tuberculosis complex. Restriction patterns indicated that infection in the six seals was from a single source. Western blotting with monoclonal antibody to M bovis identified antigens at 23 and 27 kDa in M bovis which were absent from the seal isolates.
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Affiliation(s)
- D V Cousins
- Animal Health Laboratories, Department of Agriculture, Baron-Hay Court, South Perth, Western Australia
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Ching MS, Lennard MS, Gregory A, Tucker GT. Measurement of underivatised metoprolol enantiomers in human plasma by high-performance liquid chromatography with a chiral stationary phase. J Chromatogr 1989; 497:313-8. [PMID: 2625469 DOI: 10.1016/0378-4347(89)80035-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- M S Ching
- University Department of Pharmacology and Therapeutics, Royal Hallamshire Hospital, Sheffield, U.K
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Sealy R, Harrison GG, Morrell D, Korrubel J, Gregory A, Barry L, Blekkenhorst G, Hering ER, Fataar AB, Boniaszczuk J. A feasibility study of a new approach to clinical radiosensitisation: hypothermia and hyperbaric oxygen in combination with pharmacological vasodilatation. Br J Radiol 1986; 59:1093-8. [PMID: 3790896 DOI: 10.1259/0007-1285-59-707-1093] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
It is proposed that hyperbaric oxygen fails in the clinical situation due to a high proportion (greater than 33%) of hypoxic cells in human tumours. The means of overcoming this problem are reviewed. Additional to hyperbaric oxygenation, moderate hypothermia (30 degrees C) to allow redistribution of oxygen in the tumour is proposed. A system of externally controlled intravenous anaesthesia has been developed for the single-subject hyperbaric cylinder. Pharmacological vasodilatation is induced in the anaesthetised patient who is then fluid loaded and cooled. Initial single-sensitising treatments are advocated. Twenty-nine patients with advanced mouth cancer have completed a course of this treatment, of whom five of nine were free of disease after 2 years and 10 of 21 at 1 year, with three intercurrent deaths. Fifteen have experienced local failure. This approach would appear to be practical, safe and promising.
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