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Lines KE, Filippakopoulos P, Stevenson M, Müller S, Lockstone HE, Wright B, Knapp S, Buck D, Bountra C, Thakker RV. Effects of epigenetic pathway inhibitors on corticotroph tumour AtT20 cells. Endocr Relat Cancer 2020; 27:163-174. [PMID: 31935194 PMCID: PMC7040567 DOI: 10.1530/erc-19-0448] [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] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 01/13/2020] [Indexed: 12/13/2022]
Abstract
Medical treatments for corticotrophinomas are limited, and we therefore investigated the effects of epigenetic modulators, a new class of anti-tumour drugs, on the murine adrenocorticotropic hormone (ACTH)-secreting corticotrophinoma cell line AtT20. We found that AtT20 cells express members of the bromo and extra-terminal (BET) protein family, which bind acetylated histones, and therefore, studied the anti-proliferative and pro-apoptotic effects of two BET inhibitors, referred to as (+)-JQ1 (JQ1) and PFI-1, using CellTiter Blue and Caspase Glo assays, respectively. JQ1 and PFI-1 significantly decreased proliferation by 95% (P < 0.0005) and 43% (P < 0.0005), respectively, but only JQ1 significantly increased apoptosis by >50-fold (P < 0.0005), when compared to untreated control cells. The anti-proliferative effects of JQ1 and PFI-1 remained for 96 h after removal of the respective compound. JQ1, but not PFI-1, affected the cell cycle, as assessed by propidium iodide staining and flow cytometry, and resulted in a higher number of AtT20 cells in the sub G1 phase. RNA-sequence analysis, which was confirmed by qRT-PCR and Western blot analyses, revealed that JQ1 treatment significantly altered expression of genes involved in apoptosis, such as NFκB, and the somatostatin receptor 2 (SSTR2) anti-proliferative signalling pathway, including SSTR2. JQ1 treatment also significantly reduced transcription and protein expression of the ACTH precursor pro-opiomelanocortin (POMC) and ACTH secretion by AtT20 cells. Thus, JQ1 treatment has anti-proliferative and pro-apoptotic effects on AtT20 cells and reduces ACTH secretion, thereby indicating that BET inhibition may provide a novel approach for treatment of corticotrophinomas.
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Affiliation(s)
- K E Lines
- OCDEM, Radcliffe Department of Medicine, University of Oxford, Churchill Hospital, Oxford, UK
| | | | - M Stevenson
- OCDEM, Radcliffe Department of Medicine, University of Oxford, Churchill Hospital, Oxford, UK
| | - S Müller
- Structural Genomics Consortium, Buchmann Institute for Life Sciences, Goethe-University Frankfurt, Frankfurt, Germany
| | - H E Lockstone
- Oxford Genomics Centre, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - B Wright
- Oxford Genomics Centre, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - S Knapp
- Structural Genomics Consortium, Buchmann Institute for Life Sciences, Goethe-University Frankfurt, Frankfurt, Germany
- Institute of Pharmaceutical Chemistry, Goethe-University Frankfurt, Frankfurt, Germany
| | - D Buck
- Oxford Genomics Centre, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - C Bountra
- Structural Genomics Consortium, University of Oxford, Oxford, UK
| | - R V Thakker
- OCDEM, Radcliffe Department of Medicine, University of Oxford, Churchill Hospital, Oxford, UK
- Correspondence should be addressed to R V Thakker:
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2
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Singh K, Batouli A, Buck D. 4:03 PM Abstract No. 20 Splenic artery embolization: does severity of injury, type of embolic agent used, or location of embolization affect outcomes? J Vasc Interv Radiol 2018. [DOI: 10.1016/j.jvir.2018.01.026] [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: 10/17/2022] Open
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3
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Buck D, Shields GE, Elvidge J, Hayhurst K, Davies LM. OP14 A systematic review of cost-effectiveness evaluations of psychological therapies for schizophrenia and bipolar disorder. Health Serv Res 2017. [DOI: 10.1136/jech-2017-ssmabstracts.14] [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] Open
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4
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Lines KE, Stevenson M, Filippakopoulos P, Müller S, Lockstone HE, Wright B, Grozinsky-Glasberg S, Grossman AB, Knapp S, Buck D, Bountra C, Thakker RV. Epigenetic pathway inhibitors represent potential drugs for treating pancreatic and bronchial neuroendocrine tumors. Oncogenesis 2017; 6:e332. [PMID: 28504695 PMCID: PMC5523063 DOI: 10.1038/oncsis.2017.30] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Revised: 03/24/2017] [Accepted: 03/28/2017] [Indexed: 02/06/2023] Open
Abstract
Cancer is associated with alterations in epigenetic mechanisms such as histone modifications and methylation of DNA, and inhibitors targeting epigenetic mechanisms represent a novel class of anti-cancer drugs. Neuroendocrine tumors (NETs) of the pancreas (PNETs) and bronchus (BNETs), which may have 5-year survivals of <50% and as low as 5%, respectively, represent targets for such drugs, as >40% of PNETs and ~35% of BNETs have mutations of the multiple endocrine neoplasia type 1 (MEN1) gene, which encodes menin that modifies histones by interacting with histone methyltransferases. We assessed 9 inhibitors of epigenetic pathways, for their effects on proliferation, by CellTiter Blue assay, and apoptosis, by CaspaseGlo assay, using 1 PNET and 2 BNET cell lines. Two inhibitors, referred to as (+)-JQ1 (JQ1) and PFI-1, targeting the bromo and extra terminal (BET) protein family which bind acetylated histone residues, were most effective in decreasing proliferation (by 40-85%, P<0.001) and increasing apoptosis (by 2-3.6 fold, P<0.001) in all 3 NET cell lines. The anti-proliferative effects of JQ1 and PFI-1 remained present for at least 48 hours after removal of the compound. JQ1, but not PFI-1, had cell cycle effects, assessed by propidium iodide staining and flow cytometry, resulting in increased and decreased proportions of NET cells in G1, and S and G2 phases, respectively. RNA Sequencing analysis revealed that these JQ1 effects were associated with increased histone 2B expression, and likely mediated through altered activity of bromodomain-containing (Brd) proteins. Assessment of JQ1 in vivo, using a pancreatic beta cell-specific conditional Men1 knockout mouse model that develops PNETs, revealed that JQ1 significantly reduced proliferation (by ~50%, P<0.0005), assessed by bromodeoxyuridine incorporation, and increased apoptosis (by ~3 fold, P<0.0005), assessed by terminal deoxynucleotidyl transferase dUTP nick end labelling, of PNETs. Thus, our studies demonstrate that BET protein inhibitors may provide new treatments for NETs.
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Affiliation(s)
- K E Lines
- Academic Endocrine Unit, OCDEM, University of Oxford, Churchill Hospital, Headington, Oxford, UK
| | - M Stevenson
- Academic Endocrine Unit, OCDEM, University of Oxford, Churchill Hospital, Headington, Oxford, UK
| | - P Filippakopoulos
- Structural Genomics Consortium, University of Oxford, Old Road Campus, Headington, Oxford, UK
| | - S Müller
- Structural Genomics Consortium, University of Oxford, Old Road Campus, Headington, Oxford, UK
| | - H E Lockstone
- Oxford Genomics Centre, Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, UK
| | - B Wright
- Oxford Genomics Centre, Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, UK
| | - S Grozinsky-Glasberg
- Neuroendocrine Tumor Unit, Endocrinology & Metabolism Service, Department of Medicine, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - A B Grossman
- Academic Endocrine Unit, OCDEM, University of Oxford, Churchill Hospital, Headington, Oxford, UK
| | - S Knapp
- Structural Genomics Consortium, University of Oxford, Old Road Campus, Headington, Oxford, UK
- Institute for Pharmaceutical Chemistry, Johann Wolfgang Goethe-University and Buchmann Institute for Molecular Life Sciences, Max-von-Laue-Strasse 9, Frankfurt am Main, Jerusalem, Germany
| | - D Buck
- Oxford Genomics Centre, Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, UK
| | - C Bountra
- Structural Genomics Consortium, University of Oxford, Old Road Campus, Headington, Oxford, UK
| | - R V Thakker
- Academic Endocrine Unit, OCDEM, University of Oxford, Churchill Hospital, Headington, Oxford, UK
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5
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South J, Southby K, James M, Tree D, Buck D. Exploring the links between volunteering, health and inequalities – is this a public health issue? Eur J Public Health 2016. [DOI: 10.1093/eurpub/ckw171.013] [Citation(s) in RCA: 1] [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: 11/12/2022] Open
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6
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Beer A, Biberacher V, Schmidt P, Righart R, Buck D, Berthele A, Kirschke J, Zimmer C, Hemmer B, Mühlau M. Tissue damage within normal appearing white matter in early multiple sclerosis: assessment by the ratio of T1- and T2-weighted MR image intensity. J Neurol 2016; 263:1495-502. [PMID: 27178000 DOI: 10.1007/s00415-016-8156-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Revised: 04/11/2016] [Accepted: 04/29/2016] [Indexed: 11/24/2022]
Abstract
Histopathological and magnetic resonance imaging (MRI) studies have shown white matter (WM) damage in early stages of multiple sclerosis (MS) beyond the apparent T2-hyperintense lesions. These changes in normal appearing WM (NAWM) are important with regard to the clinical picture and prognosis. However, the detection of changes within NAWM has so far required special imaging techniques commonly not available in clinical routine and, hence, at large scale. The purpose of this study was to detect MS-related damage of NAWM by conventional MRI. As, within NAWM, the myelin content mainly drives the T1-weighted (T1w) signal, we scaled it by the T2w signal. We tested the hypothesis that the mean T1w/T2w ratio of NAWM is decreased in MS compared to healthy controls (HC) and that it correlates with clinical measures. We developed a pipeline to determine the individual mean values of this ratio within NAWM. We studied 244 patients in early disease stages of MS (mean age 37 ± 10 years, mean disease duration 3.1 ± 2.3, Expanded Disability Status Scale 1.3 ± 1), and 78 HC (mean age 31 ± 8 years). Compared to HC, the mean T1w/T2w ratio was lowered in the patient group (P < 0.001). The difference remained significant after restricting the analysis to patients with a disease duration of 5 years or less and without disease modifying drugs. Our measures also correlated with clinical scores. We believe that the mean T1w/T2w ratio is a promising candidate to assess MS-related tissue damage within NAWM at large scale.
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Affiliation(s)
- A Beer
- Department of Neurology, Technische Universität München, Ismaninger Straße 22, 81675, Munich, Germany.,TUM-Neuroimaging Center, Technische Universität München, Munich, Germany
| | - V Biberacher
- Department of Neurology, Technische Universität München, Ismaninger Straße 22, 81675, Munich, Germany.,TUM-Neuroimaging Center, Technische Universität München, Munich, Germany
| | - P Schmidt
- Department of Neurology, Technische Universität München, Ismaninger Straße 22, 81675, Munich, Germany.,TUM-Neuroimaging Center, Technische Universität München, Munich, Germany.,Department of Statistics, Ludwig-Maximilians-Universität München, Munich, Germany
| | - R Righart
- Department of Neurology, Technische Universität München, Ismaninger Straße 22, 81675, Munich, Germany.,TUM-Neuroimaging Center, Technische Universität München, Munich, Germany
| | - D Buck
- Department of Neurology, Technische Universität München, Ismaninger Straße 22, 81675, Munich, Germany
| | - A Berthele
- Department of Neurology, Technische Universität München, Ismaninger Straße 22, 81675, Munich, Germany
| | - J Kirschke
- Department of Neuroradiology, Technische Universität München, Munich, Germany
| | - C Zimmer
- TUM-Neuroimaging Center, Technische Universität München, Munich, Germany.,Department of Neuroradiology, Technische Universität München, Munich, Germany
| | - B Hemmer
- Department of Neurology, Technische Universität München, Ismaninger Straße 22, 81675, Munich, Germany.,Munich Cluster for Systems Neurology, Munich, Germany
| | - M Mühlau
- Department of Neurology, Technische Universität München, Ismaninger Straße 22, 81675, Munich, Germany. .,TUM-Neuroimaging Center, Technische Universität München, Munich, Germany. .,Munich Cluster for Systems Neurology, Munich, Germany.
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7
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Cohen B, Roth E, Buck D. Periprocedural management of common and new anticoagulation and antiplatelet therapies for the interventional radiologist. J Vasc Interv Radiol 2016. [DOI: 10.1016/j.jvir.2015.12.699] [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: 10/22/2022] Open
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8
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Li F, Buck D, De Winter J, Kolb J, Meng H, Birch C, Slater R, Escobar YN, Smith JE, Yang L, Konhilas J, Lawlor MW, Ottenheijm C, Granzier HL. Nebulin deficiency in adult muscle causes sarcomere defects and muscle-type-dependent changes in trophicity: novel insights in nemaline myopathy. Hum Mol Genet 2015; 24:5219-33. [PMID: 26123491 DOI: 10.1093/hmg/ddv243] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Accepted: 06/22/2015] [Indexed: 01/07/2023] Open
Abstract
Nebulin is a giant filamentous protein that is coextensive with the actin filaments of the skeletal muscle sarcomere. Nebulin mutations are the main cause of nemaline myopathy (NEM), with typical adult patients having low expression of nebulin, yet the roles of nebulin in adult muscle remain poorly understood. To establish nebulin's functional roles in adult muscle, we studied a novel conditional nebulin KO (Neb cKO) mouse model in which nebulin deletion was driven by the muscle creatine kinase (MCK) promotor. Neb cKO mice are born with high nebulin levels in their skeletal muscles, but within weeks after birth nebulin expression rapidly falls to barely detectable levels Surprisingly, a large fraction of the mice survive to adulthood with low nebulin levels (<5% of control), contain nemaline rods and undergo fiber-type switching toward oxidative types. Nebulin deficiency causes a large deficit in specific force, and mechanistic studies provide evidence that a reduced fraction of force-generating cross-bridges and shortened thin filaments contribute to the force deficit. Muscles rich in glycolytic fibers upregulate proteolysis pathways (MuRF-1, Fbxo30/MUSA1, Gadd45a) and undergo hypotrophy with smaller cross-sectional areas (CSAs), worsening their force deficit. Muscles rich in oxidative fibers do not have smaller weights and can even have hypertrophy, offsetting their specific-force deficit. These studies reveal nebulin as critically important for force development and trophicity in adult muscle. The Neb cKO phenocopies important aspects of NEM (muscle weakness, oxidative fiber-type predominance, variable trophicity effects, nemaline rods) and will be highly useful to test therapeutic approaches to ameliorate muscle weakness.
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Affiliation(s)
- Frank Li
- Department of Cellular and Molecular Medicine
| | | | - Josine De Winter
- Department of Physiology, VU University Medical Center, Amsterdam, The Netherlands
| | - Justin Kolb
- Department of Cellular and Molecular Medicine
| | - Hui Meng
- Department of Pathology and Laboratory Medicine, Medical College of Wisconsin, Milwaukee, WI, USA and
| | - Camille Birch
- Department of Physiology, University of Arizona, Tucson, AZ, USA
| | | | | | | | - Lin Yang
- Department of Biomedical Engineering, University of Florida, Gainesville, FL, USA
| | - John Konhilas
- Department of Physiology, University of Arizona, Tucson, AZ, USA
| | - Michael W Lawlor
- Department of Pathology and Laboratory Medicine, Medical College of Wisconsin, Milwaukee, WI, USA and
| | - Coen Ottenheijm
- Department of Cellular and Molecular Medicine, Department of Physiology, VU University Medical Center, Amsterdam, The Netherlands
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9
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Watts P, Buck D, Netuveli G, Renton A. Clustering of lifestyle risk behaviours among residents of forty deprived neighbourhoods in London: lessons for targeting public health interventions. J Public Health (Oxf) 2015; 38:308-15. [PMID: 25762701 DOI: 10.1093/pubmed/fdv028] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Clustering of lifestyle risk behaviours is very important in predicting premature mortality. Understanding the extent to which risk behaviours are clustered in deprived communities is vital to most effectively target public health interventions. METHODS We examined co-occurrence and associations between risk behaviours (smoking, alcohol consumption, poor diet, low physical activity and high sedentary time) reported by adults living in deprived London neighbourhoods. Associations between sociodemographic characteristics and clustered risk behaviours were examined. Latent class analysis was used to identify underlying clustering of behaviours. RESULTS Over 90% of respondents reported at least one risk behaviour. Reporting specific risk behaviours predicted reporting of further risk behaviours. Latent class analyses revealed four underlying classes. Membership of a maximal risk behaviour class was more likely for young, white males who were unable to work. CONCLUSIONS Compared with recent national level analysis, there was a weaker relationship between education and clustering of behaviours and a very high prevalence of clustering of risk behaviours in those unable to work. Young, white men who report difficulty managing on income were at high risk of reporting multiple risk behaviours. These groups may be an important target for interventions to reduce premature mortality caused by multiple risk behaviours.
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Affiliation(s)
- P Watts
- Institute for Health and Human Development, University of East London, London E15 4LZ, UK
| | - D Buck
- The King's Fund, London W1G OAN, UK
| | - G Netuveli
- Institute for Health and Human Development, University of East London, London E15 4LZ, UK
| | - A Renton
- Institute for Health and Human Development, University of East London, London E15 4LZ, UK
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10
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Nischwitz S, Wolf C, Andlauer TFM, Czamara D, Zettl UK, Rieckmann P, Buck D, Ising M, Bettecken T, Mueller-Myhsok B, Weber F. MS susceptibility is not affected by single nucleotide polymorphisms in the MMP9 gene. J Neuroimmunol 2015; 279:46-9. [PMID: 25670000 DOI: 10.1016/j.jneuroim.2015.01.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Revised: 01/21/2015] [Accepted: 01/22/2015] [Indexed: 10/24/2022]
Abstract
Matrix metalloproteinase 9 (MMP9) plays an important role in the pathogenesis of multiple sclerosis (MS). However, the impact of genetic variants affecting MMP9 on MS susceptibility is still in debate. We could not detect an association of MMP9 SNPs with MS on a genome-wide significance level by SNP genotyping, followed by imputation of SNPs within a region stretching 2Mbp up- and down-stream of MMP9. Rs6073751, located within WFDC2, was found associated with MS most strongly. Rs3918242, associated with MS according to previous reports, showed nominal significance only. Meta-analysis of our own and published data did not confirm this effect.
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Affiliation(s)
- S Nischwitz
- Max Planck Institute of Psychiatry, Kraepelinstr. 2-10, 80804 Munich, Germany.
| | - C Wolf
- Max Planck Institute of Psychiatry, Kraepelinstr. 2-10, 80804 Munich, Germany
| | - T F M Andlauer
- Max Planck Institute of Psychiatry, Kraepelinstr. 2-10, 80804 Munich, Germany
| | - D Czamara
- Max Planck Institute of Psychiatry, Kraepelinstr. 2-10, 80804 Munich, Germany
| | - U K Zettl
- Department of Neurology, University of Rostock, Gehlsheimer Straße 20, 18147 Rostock, Germany
| | - P Rieckmann
- Department of Neurology, Sozialstiftung Bamberg, Buger Straße 80, 96049 Bamberg, Germany
| | - D Buck
- Department of Neurology, TU München, Ismaninger Str. 22, 81675 München, Germany
| | - M Ising
- Max Planck Institute of Psychiatry, Kraepelinstr. 2-10, 80804 Munich, Germany
| | - T Bettecken
- Max Planck Institute of Psychiatry, Kraepelinstr. 2-10, 80804 Munich, Germany
| | - B Mueller-Myhsok
- Max Planck Institute of Psychiatry, Kraepelinstr. 2-10, 80804 Munich, Germany
| | - F Weber
- Max Planck Institute of Psychiatry, Kraepelinstr. 2-10, 80804 Munich, Germany
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11
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Kam JK, Buck D, Dawkins R, Sandhu SS, Allen PJ. Prophylactic intracameral antibiotic use during cataract surgery: response. Clin Exp Ophthalmol 2014; 43:495-6. [PMID: 25376177 DOI: 10.1111/ceo.12470] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Accepted: 11/04/2014] [Indexed: 11/28/2022]
Affiliation(s)
- Jonathan K Kam
- Department of Ophthalmology, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
| | - Danielle Buck
- Department of Ophthalmology, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
| | - Rosie Dawkins
- Department of Ophthalmology, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
| | - Sukhpal S Sandhu
- Department of Ophthalmology, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia.,Department of Ophthalmology, Centre for Eye Research Australia, Melbourne, Victoria, Australia
| | - Penelope J Allen
- Department of Ophthalmology, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia.,Department of Ophthalmology, Centre for Eye Research Australia, Melbourne, Victoria, Australia
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12
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Buck D, Smith JE, Chung CS, Ono Y, Sorimachi H, Labeit S, Granzier HL. Removal of immunoglobulin-like domains from titin's spring segment alters titin splicing in mouse skeletal muscle and causes myopathy. ACTA ACUST UNITED AC 2014; 143:215-30. [PMID: 24470489 PMCID: PMC4001778 DOI: 10.1085/jgp.201311129] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Changes in titin splicing resulting in decreased size and increased stiffness lead to pathological changes in skeletal muscle. Titin is a molecular spring that determines the passive stiffness of muscle cells. Changes in titin’s stiffness occur in various myopathies, but whether these are a cause or an effect of the disease is unknown. We studied a novel mouse model in which titin’s stiffness was slightly increased by deleting nine immunoglobulin (Ig)-like domains from titin’s constitutively expressed proximal tandem Ig segment (IG KO). KO mice displayed mild kyphosis, a phenotype commonly associated with skeletal muscle myopathy. Slow muscles were atrophic with alterations in myosin isoform expression; functional studies in soleus muscle revealed a reduced specific twitch force. Exon expression analysis showed that KO mice underwent additional changes in titin splicing to yield smaller than expected titin isoforms that were much stiffer than expected. Additionally, splicing occurred in the PEVK region of titin, a finding confirmed at the protein level. The titin-binding protein Ankrd1 was highly increased in the IG KO, but this did not play a role in generating small titin isoforms because titin expression was unaltered in IG KO mice crossed with Ankrd1-deficient mice. In contrast, the splicing factor RBM20 (RNA-binding motif 20) was also significantly increased in IG KO mice, and additional differential splicing was reversed in IG KO mice crossed with a mouse with reduced RBM20 activity. Thus, increasing titin’s stiffness triggers pathological changes in skeletal muscle, with an important role played by RBM20.
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Affiliation(s)
- Danielle Buck
- Department of Physiology and 2 Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ 85721
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13
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Ottenheijm C, Buck D, de Winter J, Ferrara C, Piroddi N, Tesi C, Jasper R, Malik F, Meng F, Stienen G, Beggs A, Labeit S, Poggesi C, Lawlor M, Granzier H. P.9.10 Deleting exon 55 from the nebulin gene induces severe muscle weakness in a mouse model for nemaline myopathy. Neuromuscul Disord 2013. [DOI: 10.1016/j.nmd.2013.06.523] [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: 10/26/2022]
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14
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Kam JK, Buck D, Dawkins R, Sandhu SS, Allen PJ. Survey of prophylactic intracameral antibiotic use in cataract surgery in an Australian context. Clin Exp Ophthalmol 2013; 42:398-400. [PMID: 23980721 DOI: 10.1111/ceo.12199] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jonathan K Kam
- Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
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15
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Ottenheijm CAC, Buck D, de Winter JM, Ferrara C, Piroddi N, Tesi C, Jasper JR, Malik FI, Meng H, Stienen GJM, Beggs AH, Labeit S, Poggesi C, Lawlor MW, Granzier H. Deleting exon 55 from the nebulin gene induces severe muscle weakness in a mouse model for nemaline myopathy. ACTA ACUST UNITED AC 2013; 136:1718-31. [PMID: 23715096 DOI: 10.1093/brain/awt113] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Nebulin--a giant sarcomeric protein--plays a pivotal role in skeletal muscle contractility by specifying thin filament length and function. Although mutations in the gene encoding nebulin (NEB) are a frequent cause of nemaline myopathy, the most common non-dystrophic congenital myopathy, the mechanisms by which mutations in NEB cause muscle weakness remain largely unknown. To better understand these mechanisms, we have generated a mouse model in which Neb exon 55 is deleted (Neb(ΔExon55)) to replicate a founder mutation seen frequently in patients with nemaline myopathy with Ashkenazi Jewish heritage. Neb(ΔExon55) mice are born close to Mendelian ratios, but show growth retardation after birth. Electron microscopy studies show nemaline bodies--a hallmark feature of nemaline myopathy--in muscle fibres from Neb(ΔExon55) mice. Western blotting studies with nebulin-specific antibodies reveal reduced nebulin levels in muscle from Neb(ΔExon55) mice, and immunofluorescence confocal microscopy studies with tropomodulin antibodies and phalloidin reveal that thin filament length is significantly reduced. In line with reduced thin filament length, the maximal force generating capacity of permeabilized muscle fibres and single myofibrils is reduced in Neb(ΔExon55) mice with a more pronounced reduction at longer sarcomere lengths. Finally, in Neb(ΔExon55) mice the regulation of contraction is impaired, as evidenced by marked changes in crossbridge cycling kinetics and by a reduction of the calcium sensitivity of force generation. A novel drug that facilitates calcium binding to the thin filament significantly augmented the calcium sensitivity of submaximal force to levels that exceed those observed in untreated control muscle. In conclusion, we have characterized the first nebulin-based nemaline myopathy model, which recapitulates important features of the phenotype observed in patients harbouring this particular mutation, and which has severe muscle weakness caused by thin filament dysfunction.
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Affiliation(s)
- Coen A C Ottenheijm
- Department of Physiology, VU University Medical Centre, Amsterdam, The Netherlands
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de Winter JM, Buck D, Hidalgo C, Jasper JR, Malik FI, Clarke NF, Stienen GJM, Lawlor MW, Beggs AH, Ottenheijm CAC, Granzier H. Troponin activator augments muscle force in nemaline myopathy patients with nebulin mutations. J Med Genet 2013; 50:383-92. [PMID: 23572184 PMCID: PMC3865762 DOI: 10.1136/jmedgenet-2012-101470] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [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] [Indexed: 02/06/2023]
Abstract
Background Nemaline myopathy—the most common non-dystrophic congenital myopathy—is caused by mutations in thin filament genes, of which the nebulin gene is the most frequently affected one. The nebulin gene codes for the giant sarcomeric protein nebulin, which plays a crucial role in skeletal muscle contractile performance. Muscle weakness is a hallmark feature of nemaline myopathy patients with nebulin mutations, and is caused by changes in contractile protein function, including a lower calcium-sensitivity of force generation. To date no therapy exists to treat muscle weakness in nemaline myopathy. Here, we studied the ability of the novel fast skeletal muscle troponin activator, CK-2066260, to augment force generation at submaximal calcium levels in muscle cells from nemaline myopathy patients with nebulin mutations. Methods Contractile protein function was determined in permeabilised muscle cells isolated from frozen patient biopsies. The effect of 5 µM CK-2066260 on force production was assessed. Results Nebulin protein concentrations were severely reduced in muscle cells from these patients compared to controls, while myofibrillar ultrastructure was largely preserved. Both maximal active tension and the calcium-sensitivity of force generation were lower in patients compared to controls. Importantly, CK-2066260 greatly increased the calcium-sensitivity of force generation—without affecting the cooperativity of activation—in patients to levels that exceed those observed in untreated control muscle. Conclusions Fast skeletal troponin activation is a therapeutic mechanism to augment contractile protein function in nemaline myopathy patients with nebulin mutations and with other neuromuscular diseases.
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Affiliation(s)
- Josine Marieke de Winter
- Department of Physiology, Institute for Cardiovascular Research, VU University Medical Center, Amsterdam, The Netherlands
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Lee EJ, De Winter JM, Buck D, Jasper JR, Malik FI, Labeit S, Ottenheijm CA, Granzier H. Fast skeletal muscle troponin activation increases force of mouse fast skeletal muscle and ameliorates weakness due to nebulin-deficiency. PLoS One 2013; 8:e55861. [PMID: 23437068 PMCID: PMC3577798 DOI: 10.1371/journal.pone.0055861] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2012] [Accepted: 01/03/2013] [Indexed: 11/18/2022] Open
Abstract
The effect of the fast skeletal muscle troponin activator, CK-2066260, on calcium-induced force development was studied in skinned fast skeletal muscle fibers from wildtype (WT) and nebulin deficient (NEB KO) mice. Nebulin is a sarcomeric protein that when absent (NEB KO mouse) or present at low levels (nemaline myopathy (NM) patients with NEB mutations) causes muscle weakness. We studied the effect of fast skeletal troponin activation on WT muscle and tested whether it might be a therapeutic mechanism to increase muscle strength in nebulin deficient muscle. We measured tension-pCa relations with and without added CK-2066260. Maximal active tension in NEB KO tibialis cranialis fibers in the absence of CK-2066260 was ∼60% less than in WT fibers, consistent with earlier work. CK-2066260 shifted the tension-calcium relationship leftwards, with the largest relative increase (up to 8-fold) at low to intermediate calcium levels. This was a general effect that was present in both WT and NEB KO fiber bundles. At pCa levels above ∼6.0 (i.e., calcium concentrations <1 µM), CK-2066260 increased tension of NEB KO fibers to beyond that of WT fibers. Crossbridge cycling kinetics were studied by measuring k(tr) (rate constant of force redevelopment following a rapid shortening/restretch). CK-2066260 greatly increased k(tr) at submaximal activation levels in both WT and NEB KO fiber bundles. We also studied the sarcomere length (SL) dependence of the CK-2066260 effect (SL 2.1 µm and 2.6 µm) and found that in the NEB KO fibers, CK-2066260 had a larger effect on calcium sensitivity at the long SL. We conclude that fast skeletal muscle troponin activation increases force at submaximal activation in both wildtype and NEB KO fiber bundles and, importantly, that this troponin activation is a potential therapeutic mechanism for increasing force in NM and other skeletal muscle diseases with loss of muscle strength.
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Affiliation(s)
- Eun-Jeong Lee
- Department of Physiology, University of Arizona, Tucson, Arizona, United States of America
| | - Josine M. De Winter
- Institute for Cardiovascular Research, Department of Physiology, VU University Medical Center Amsterdam, Amsterdam, The Netherlands
| | - Danielle Buck
- Department of Physiology, University of Arizona, Tucson, Arizona, United States of America
| | - Jeffrey R. Jasper
- Research & Early Development, Cytokinetics, Inc., South San Francisco, California, United States of America
| | - Fady I. Malik
- Research & Early Development, Cytokinetics, Inc., South San Francisco, California, United States of America
| | - Siegfried Labeit
- Department of Integrative Pathophysiology, Universitätsmedizin Mannheim, University of Heidelberg, Mannheim, Germany
| | - Coen A. Ottenheijm
- Department of Physiology, University of Arizona, Tucson, Arizona, United States of America
- Institute for Cardiovascular Research, Department of Physiology, VU University Medical Center Amsterdam, Amsterdam, The Netherlands
| | - Henk Granzier
- Department of Physiology, University of Arizona, Tucson, Arizona, United States of America
- * E-mail:
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Ottenheijm C, Buck D, de Winter J, Lawlor M, Stienen G, Beggs A, Labeit S, Granzier H. A Novel Mouse Model of Nebulin-Based Nemaline Myopathy. Biophys J 2013. [DOI: 10.1016/j.bpj.2012.11.246] [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: 10/27/2022] Open
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Ferrara C, Buck D, Piroddi N, Tesi C, LeWinter J, Ottenheijm C, Poggesi C, Granzier H. Altered Cross Bridge Kinetics in Skeletal Myofibrils from NEBΔex55, a Novel Mouse Model of Nebulin-Based Nemaline Myopathy. Biophys J 2013. [DOI: 10.1016/j.bpj.2012.11.2669] [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: 10/27/2022] Open
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20
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Buck D, Albrecht E, Aslam M, Hauenstein N, Jochim A, Cepok S, Grummel V, Berthele A, Lichtner P, Gieger C, Winkelmann J, Hemmer B. Genetic Determinants of IgG Synthesis in the Cerebrospinal Fluid of Patients with Multiple Sclerosis (S20.006). Neurology 2012. [DOI: 10.1212/wnl.78.1_meetingabstracts.s20.006] [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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Kowarik MC, Pellkofer HL, Cepok S, Korn T, Kümpfel T, Buck D, Hohlfeld R, Berthele A, Hemmer B. Differential effects of fingolimod (FTY720) on immune cells in the CSF and blood of patients with MS. Neurology 2011; 76:1214-21. [PMID: 21464424 DOI: 10.1212/wnl.0b013e3182143564] [Citation(s) in RCA: 124] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND The oral immunomodulator fingolimod (FTY720) has recently been shown to be highly effective in relapsing-remitting multiple sclerosis (MS). Fingolimod is a functional antagonist of the sphingosine-1-phosphate receptor 1 and thereby inhibits sphingosine-1-phosphate-dependent lymphocyte egress from secondary lymphoid tissues, resulting in a pronounced lymphopenia in the peripheral blood. The effects of fingolimod treatment on the CSF of patients with MS have not been studied so far. METHODS We analyzed the leukocyte count, albumin quotient, immunoglobulin G (IgG) index, and oligoclonal bands in the CSF of fingolimod-treated patients with MS. Moreover, we performed immunophenotyping of CSF and peripheral blood leukocytes by flow cytometry. The results were compared to those from treatment-naive or natalizumab-treated patients with MS and patients with other inflammatory and noninflammatory neurologic diseases. RESULTS Fingolimod therapy significantly decreased CSF leukocyte counts, but had little impact on the extent of intrathecal IgG synthesis and presence of oligoclonal bands in the CSF. Fingolimod decreased the proportion of CSF CD4+ T cells but to a lesser extent than in the peripheral blood. While fingolimod strongly reduced B cells in the periphery, it had little impact on B cells in the CSF. The percentage of CSF CD8+ T cells, NK cells, and monocytes increased compared to treatment-naive patients. The CD4+/CD8+ T-cell ratio in CSF reversed in most of the patients. CONCLUSION Fingolimod treatment has a profound impact on CSF, which to some extent differs from the peripheral effects of the drug.
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Affiliation(s)
- M C Kowarik
- Department of Neurology, Klinikum Rechts der Isar, Technische Universität München, Munich, Germany
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Weber F, Cepok S, Wolf C, Berthele A, Uhr M, Bettecken T, Buck D, Hartung HP, Holsboer F, Müller-Myhsok B, Hemmer B. Single-nucleotide polymorphisms in HLA- and non-HLA genes associated with the development of antibodies to interferon-β therapy in multiple sclerosis patients. Pharmacogenomics J 2011; 12:238-45. [PMID: 21502966 DOI: 10.1038/tpj.2011.14] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Interferons-β (IFN-β) are the most widely used immunomodulatory drugs for treatment of multiple sclerosis (MS). The development of neutralizing antibodies (NABs) against IFN-β is one of the main reasons for treatment failure. While formulation of the drug has a proven impact on the development of NABs, the genetic predisposition to develop antibodies is poorly understood. We performed genome-wide single-nucleotide polymorphism (SNP) genotyping in 362 MS patients of whom 178 had developed and 184 had not developed antibodies on IFN-β therapy. Four candidate SNPs were validated in an independent cohort of 350 antibody-positive and 468 antibody-negative MS patients. One SNP within the human leucocyte antigen (HLA) region (rs9272105, P-value: 3.56 × 10⁻¹⁰) and one SNP in an intergenic region on chromosome 8q24.3 (rs4961252, P-value: 2.92 × 10⁻⁸ showed a genome-wide significant association with the anti-IFN-β antibody titers. We found no interaction between the genome-wide significant SNPs (rs9272105 and rs4961252) in our study and the previously described HLA-DR*0401 or *0408 alleles, indicating an additive effect of SNPs and HLA alleles. Testing for these SNPs and the HLA-DR*0401 or *0408 alleles allows to identify patients at risk to develop antibodies to IFN-β and may provide helpful information for individual treatment decisions.
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Affiliation(s)
- F Weber
- Max Planck Institute of Psychiatry, Munich, Germany
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Blumchen K, Bayer P, Buck D, Michael T, Cremer R, Fricke C, Henne T, Peters H, Hofmann U, Keil T, Schlaud M, Wahn U, Niggemann B. Effects of latex avoidance on latex sensitization, atopy and allergic diseases in patients with spina bifida. Allergy 2010; 65:1585-93. [PMID: 20659078 DOI: 10.1111/j.1398-9995.2010.02447.x] [Citation(s) in RCA: 19] [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] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
BACKGROUND Ten years ago, avoidance measures such as the performance of latex-free operations were implemented in children with spina bifida. Since then, latex sensitization and latex allergy have decreased in this high-risk group. OBJECTIVE To study the effect of primary latex-free prophylaxis on the prevalence of allergic diseases and atopy as a marker for sensitization spreading in children with spina bifida. METHODS One hundred and twenty children with spina bifida born after the introduction of latex-free prophylaxis and operated on under latex-free conditions ('current group') were examined for latex sensitization, latex allergy, sensitization to aero- and food allergens and allergic diseases. Results were compared to a 'historic' (not latex-free operated) group of children with spina bifida and comparable age (n = 87) and to a recent sample of children from the general population (n = 12,403). RESULTS In comparison with the 'historic group', latex sensitization (55% vs 5%, P < 0.001) and latex allergy (37% vs 0.8%, P < 0.001) were significantly reduced in the 'current group'. Furthermore, a significant reduction could be demonstrated for sensitization to aeroallergens (41.4% vs 20.8%, P = 0.001) and for allergic diseases (35% vs 15%, P = 0.001). The prevalence for atopy, sensitization to aero-/foodallergens and for allergic diseases in children of the 'current group' was similar to those in children of the weighted population sample. CONCLUSIONS Latex avoidance in children with spina bifida prevents latex sensitization and latex allergy. Additionally, it also seems to prevent sensitization to other allergens and allergic diseases which might be explained by the prevention of sensitization spreading.
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Affiliation(s)
- K Blumchen
- Department of Pediatric Pneumology and Immunology, Charité University Medicine, Berlin, Germany.
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Schoebel C, Bangha-Szabo D, Sebert M, Buck D, Fietze I, Baumann G, Vogtmann T, Penzel T. Vergleich von Berlin Questionnaire und Polygrafie bei Patienten mit Vorhofflimmern. Pneumologie 2010. [DOI: 10.1055/s-0030-1267746] [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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Buck D, Hudson BD, Ottenheijm CA, Labeit S, Granzier H. Differential splicing of the large sarcomeric protein nebulin during skeletal muscle development. J Struct Biol 2010; 170:325-33. [PMID: 20176113 PMCID: PMC2856706 DOI: 10.1016/j.jsb.2010.02.014] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2009] [Revised: 02/15/2010] [Accepted: 02/16/2010] [Indexed: 01/08/2023]
Abstract
We studied differential splicing of nebulin, a giant filamentous F-actin binding protein (M(r) approximately 700-800kDa) that is found in skeletal muscle. Nebulin spans the thin filament length, its C-terminus is anchored in the Z-disc, and its N-terminal region is located toward the thin filament pointed end. Various lines of evidence indicate that nebulin plays important roles in thin filament and Z-disc structure in skeletal muscle. In the present work we studied nebulin in a range of muscle types during postnatal development and performed transcript studies with a mouse nebulin exon microarray, developed by us, whose results were confirmed by RT-PCR. We also performed protein studies with high-resolution SDS-agarose gels and Western blots, and structural studies with electron microscopy. We found during postnatal development of the soleus muscle major changes in splicing in both the super-repeat region and the Z-disc region of nebulin; interestingly, these changes were absent in other muscle types. Three novel Z-disc exons, previously described in the mouse gene, were upregulated during postnatal development of soleus muscle and this was correlated with a significant increase in Z-disc width. These findings support the view that nebulin plays an important role in Z-disc width regulation. In summary, we discovered changes in both the super-repeat region and the Z-disc region of nebulin, that these changes are muscle-type specific, and that they correlate with differences in sarcomere structure.
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Affiliation(s)
- Danielle Buck
- Depts of Physiology and Molecular and Cellular Biology, University of Arizona, Tucson, AZ 85724, USA
| | - Bryan D. Hudson
- Depts of Physiology and Molecular and Cellular Biology, University of Arizona, Tucson, AZ 85724, USA
| | - Coen A.C. Ottenheijm
- Depts of Physiology and Molecular and Cellular Biology, University of Arizona, Tucson, AZ 85724, USA
- Laboratory for Physiology, Institute for Cardiovascular Research, VU University Medical Center, Amsterdam 1081 BT, the Netherlands
| | - Siegfried Labeit
- Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Henk Granzier
- Depts of Physiology and Molecular and Cellular Biology, University of Arizona, Tucson, AZ 85724, USA
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Buck D, Hoying A, Hudson B, Ottenheijm C, Granzier H. Developmentally Regulated Differential Splicing of the Large Sarcomeric Proteins Titin and Nebulin. Biophys J 2010. [DOI: 10.1016/j.bpj.2009.12.2954] [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] Open
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Buck D, Powell C, Cumberland P, Davis H, Dawson E, Rahi J, Sloper J, Taylor R, Tiffin P, Clarke MP. Presenting features and early management of childhood intermittent exotropia in the UK: inception cohort study. Br J Ophthalmol 2009; 93:1620-4. [DOI: 10.1136/bjo.2008.152975] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [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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Buck D, Godfrey C, Sutton M. Economic and other views of addiction: implications for the choice of alcohol, tobacco and drug policies. Drug Alcohol Rev 2009; 15:357-68. [PMID: 16203393 DOI: 10.1080/09595239600186121] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
It is the aim of this paper to provide an overview of developments in implicit and explicit economic views of addiction, to contrast these perceptions with the views of other disciplines and discuss the implications for policy. Addictive behaviours have received considerable attention from disciplines other than economics. The nature of addiction and the contribution of psychological, physiological and social factors have been strongly debated within the addictions field for many years. The views of economists are becoming increasingly important because economic studies of consumption, and tax revenue in the case of licit drugs, are one factor when framing policy. It is therefore crucial to know how economists have treated addiction. Have they neglected it and what are the implication if they have? This paper attempts to answer this question by reviewing and discussing the literature in depth and drawing out the implications for policy.
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Affiliation(s)
- D Buck
- Centre for Health Economics, University of York, York, YO1 5DD, UK
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Ottenheijm C, Knottnerus A, Buck D, Pecor T, Luo X, Granzier H. Titin Isoform Transitions and Passive Stiffness During Skeletal Muscle Development. Biophys J 2009. [DOI: 10.1016/j.bpj.2008.12.2572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Ringel D, Buck D, Glos M, Penzel T, Fietze I. Komplexe Apnoen unter nächtlicher Überdruckbeatmungstherapie bei Patienten mit einem Schlafapnoesyndrom. Pneumologie 2008. [DOI: 10.1055/s-0028-1083120] [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: 10/21/2022]
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Kim Y, Buck D, Glos M, Penzel T, Fietze I. Vergleich ambulanter Polygraphie mit stationärer Polysomnographie bei Schlafbezogenen Atmungsstörungen. Pneumologie 2008. [DOI: 10.1055/s-0028-1083113] [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: 10/21/2022]
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Buck D, Clarke MP, Haggerty H, Hrisos S, Powell C, Sloper J, Strong NP. Grading the severity of intermittent distance exotropia: the revised Newcastle Control Score. Br J Ophthalmol 2008; 92:577. [DOI: 10.1136/bjo.2007.120287] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Kelly DJ, Buck D, Cox AJ, Zhang Y, Gilbert RE. Effects on protein kinase C-β inhibition on glomerular vascular endothelial growth factor expression and endothelial cells in advanced experimental diabetic nephropathy. Am J Physiol Renal Physiol 2007; 293:F565-74. [PMID: 17522264 DOI: 10.1152/ajprenal.00397.2006] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [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: 11/22/2022] Open
Abstract
Ruboxistaurin is an inhibitor of the β isoform of protein kinase C (PKC-β) that reduces the actions of vascular endothelial growth factor (VEGF) and attenuates the progression of diabetic retinopathy. In the glomerulus VEGF is constitutively expressed where it likely has a role in maintaining endothelial cell integrity, particularly in disease states. Given its potential use in diabetic nephropathy, we sought to determine the effects of PKC-β inhibition on VEGF and glomerular endothelial cells in experimental diabetic nephropathy. Studies were conducted in (mRen-2)27 rat, a transgenic rodent with hypertension and an enhanced renin-angiotensin system that following induction of diabetes with streptozotocin develops many of the features of diabetic nephropathy. Moreover, to mimic the clinical context, the effects of PKC-β inhibition were examined both with and without concomitant angiotensin-converting enzyme (ACE) inhibitor therapy. Diabetic Ren-2 rats were randomized to receive either vehicle, the ACE inhibitor, perindopril (0.2 mg/l in drinking water), ruboxistaurin (10 mg·kg−1·day−1, admixed in chow), or their combination and studied for 12 wk. Diabetic Ren-2 rats displayed glomerular endothelial cell loss in association with overexpression of VEGF mRNA. Both cell loss and VEGF overexpression were attenuated by the administration of either perindopril or ruboxistaurin, as single agent treatments with their combination providing additional, incremental improvements, reducing these manifestations of injury down to levels seen in nondiabetic, normotensive, nontransgenic animals. Combination therapy was also associated with additional improvements in albuminuria and glomerulosclerosis.
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Affiliation(s)
- Darren J Kelly
- Dept. of Medicine, St. Vincent's Hospital, Fitzroy, Victoria 3065, Australia.
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Abstract
The costimulatory CD40-CD40L pathway plays a critical role in the generation and maintenance of adaptive immune responses. Genetic interference of CD40-CD40L interactions strongly influences the onset and course in many autoimmune disease models including experimental autoimmune encephalomyelitis. We analysed the association of a single nucleotide polymorphism of the CD40 gene (C/T(-1)) in 287 patients with multiple sclerosis (MS) and 184 matched controls. No significant differences were found in the frequency of the C/T(-1) polymorphism between the patients with MS and the controls (53% vs 49%) or among different MS subtypes. Cell surface expression of CD40 did not differ within the different genotypes, but carriers of the T allele showed a trend for a lower stimulatory index compared with individuals with the CC genotype. Although these subtle differences indicate functional consequences in the immune stimulatory capabilities related to the CD40 C/T(-1) polymorphism, our population-based study found no association with disease susceptibility or disease course in MS.
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Affiliation(s)
- D Buck
- Clinical Research Group for Multiple Sclerosis and Neuroimmunology, Department of Neurology, Bayerische Julius-Maximilians Universität, Würzburg, Germany
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Abstract
BACKGROUND Studies of distance stereoacuity in intermittent exotropia suggest that normal stereoacuity corresponds to good control of the deviation and that reduced or negative stereoacuity signifies poorer control. AIM : To evaluate distance stereoacuity in intermittent exotropia using the Frisby Davis Distance stereo test (FD2). METHODS Children with intermittent exotropia where the near angle was less than or equal to distance were eligible for recruitment. Standardised prospective data collection included FD2 distance stereoacuity. This was a longitudinal study in which outcomes are reported for baseline, last follow-up (> or =6 months before any surgery) or preoperative and last postoperative visits for those undergoing surgery. RESULTS 110 children with intermittent exotropia had FD2 stereoacuity tested at baseline: 70 comprehended the test. Mean (standard deviation (SD)) age was 4.6 (1.7) years (range 2-10 years). 41/70 (59%) showed positive responses: mean (SD) stereoacuity 30 (12) s of arc. The mean follow-up period before any surgery was 13 months (range 6-27 months). At follow-up, mean (SD) stereoacuity was 24 (11) s of arc. Preoperative and postoperative stereoacuity were not significantly different from those not undergoing surgery. CONCLUSION This study was the first to report distance stereoacuity in intermittent exotropia using the FD2 stereo test: patients with intermittent exotropia can achieve normal levels of distance stereoacuity, but a considerable proportion, despite comprehending, showed a negative response. This suggests that using the FD2, distance stereoacuity in intermittent exotropia is either absent or normal rather than reduced. Possible reasons for this and its implications are discussed.
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Affiliation(s)
- S R Hatt
- Department of Ophthalmology & Orthoptics, Royal Victoria Infirmary, Newcastle upon Tyne, Tyne and Wear, UK.
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Von Mehren M, Buck D, Temmer E, Elsayed YA, Cohen RB. Phase I study of trabectedin (T) in combination with docetaxel (D) in patients with advanced malignancies. J Clin Oncol 2006. [DOI: 10.1200/jco.2006.24.18_suppl.2068] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
2068 Background: T is a novel cytotoxic agent that binds to the DNA minor groove and is active in several tumor types. The objective of this study is to determine the maximum tolerated dose (MTD) of the combination. Other objectives include safety and efficacy. Methods: Eligible patients (pts) had advanced cancer, PS 0–1 and adequate organ function. Restricted pts were limited to 1 prior cytotoxic regimen, while unrestricted pts had no limit. On day 1 of each cycle, Pts received D starting at 60 mg/m2 over 1 hour followed by T starting at 0.4 mg/m2 over 3 hours. Dosing was repeated q 3 weeks. Incremental doses of both drugs were explored. PK samples were collected. A standard “3+3” dose escalation, definitions of dose limiting toxicity (DLT), and dose modifications were implemented. Results: To date, 31 pts have been treated, receiving 147 cycles (Range 1–28, median 6). At dose level 2 (D 60 mg/m2 + T 0.6 mg/m2), 2/4 unrestricted pts and 3/5 restricted pts developed DLT (grade IV neutropenia and/or febrile neutropenia) requiring institution of prophylactic filgrastim. Therapy was well tolerated after institution of filgrastim and no DLTs have been observed through the current dose level 6 (D 60 mg/m2 + T 1.3 mg/m2). Most frequently related grade 3 and 4 adverse events (AE) were: neutropenia (51%), elevated liver enzymes (3.7%), DVT (3.7%), and hyponatremia (3.7%). The most frequently related grade 1and 2 AEs were: fatigue (56%), neutropenia (56%), nausea (55%), and anemia (40%). Anti-tumor activity included a complete response in a pt with peritoneal Ca and durable prolong stable disease (SD) in 2 pts with sarcoma (20 + and 10 + months) and a pt with prostate Ca (8+ months). Another pt with gastric Ca achieved SD lasting 8 months. PK evaluations of D and T are ongoing. Conclusions: The combination of T and D with filgrastim support is safe and well-tolerated. Preliminary data suggest that this regimen is active in pts with advanced cancers. Additional cohorts are planned giving D 75 mg/m2 and T 1.3 mg/m2. [Table: see text]
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Affiliation(s)
- M. Von Mehren
- Fox Chase Cancer Center, Philadelphia, PA; Johnson & Johnson Pharmaceutical Research and Deve, Raritan, NJ
| | - D. Buck
- Fox Chase Cancer Center, Philadelphia, PA; Johnson & Johnson Pharmaceutical Research and Deve, Raritan, NJ
| | - E. Temmer
- Fox Chase Cancer Center, Philadelphia, PA; Johnson & Johnson Pharmaceutical Research and Deve, Raritan, NJ
| | - Y. A. Elsayed
- Fox Chase Cancer Center, Philadelphia, PA; Johnson & Johnson Pharmaceutical Research and Deve, Raritan, NJ
| | - R. B. Cohen
- Fox Chase Cancer Center, Philadelphia, PA; Johnson & Johnson Pharmaceutical Research and Deve, Raritan, NJ
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Jacoby A, Rannard A, Buck D, Bhala N, Newton JL, James OFW, Jones DEJ. Development, validation, and evaluation of the PBC-40, a disease specific health related quality of life measure for primary biliary cirrhosis. Gut 2005; 54:1622-9. [PMID: 15961522 PMCID: PMC1774759 DOI: 10.1136/gut.2005.065862] [Citation(s) in RCA: 168] [Impact Index Per Article: 8.8] [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: 05/19/2005] [Accepted: 06/03/2005] [Indexed: 12/11/2022]
Abstract
BACKGROUND AND AIMS Study of health related quality of life (HRQOL) and the factors responsible for its impairment in primary biliary cirrhosis (PBC) has, to date, been limited. There is increasing need for a HRQOL questionnaire which is specific to PBC. The aim of this study was to develop, validate, and evaluate a patient based PBC specific HRQOL measure. SUBJECTS AND METHODS A pool of potential questions was derived from thematic analysis of indepth interviews carried out with 30 PBC patients selected to represent demographically the PBC patient population as a whole. This pool was systematically reduced, pretested, and cross validated with other HRQOL measures in national surveys involving a total of 900 PBC patients, to produce a quality of life profile measure, the PBC-40, consisting of 40 questions distributed across six domains. The PBC-40 was then evaluated in a blinded comparison with other HRQOL measures in a further cohort of 40 PBC patients. RESULTS The six domains of PBC-40 relate to fatigue, emotional, social, and cognitive function, general symptoms, and itch. The highest mean domain score was seen for fatigue and the lowest for itch. The measure has been fully validated for use in PBC and shown to be scientifically sound. PBC patient satisfaction, measured in terms of the extent to which a questionnaire addresses the problems that they experience, was significantly higher for the PBC-40 than for other HRQOL measures. CONCLUSION The PBC-40 is a short easy to complete measure which is acceptable to PBC patients and has significantly greater relevance to their problems than other frequently used HRQOL measures. Its scientific soundness, shown in extensive testing, makes it a valuable instrument for future use in clinical and research settings.
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Affiliation(s)
- A Jacoby
- Division of Public Health, University of Liverpool, Whelan Building, The Quadrangle, Brownlow Hill, Liverpool L69 3GB, UK.
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Lauve A, Morris M, Schmidt-Ullrich R, Wu Y, Wu Q, Tong S, Johnson C, Abayomi O, Buck D, Holdford D, Dawson K, Mohan R. A phase I trial using a parotid-sparing, accelerated Intensity-Modulated Radiotherapy (IMRT) regimen to treat locally advanced head and neck squamous cell carcinoma. Int J Radiat Oncol Biol Phys 2003. [DOI: 10.1016/s0360-3016(03)01167-2] [Citation(s) in RCA: 3] [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: 11/27/2022]
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Newton JT, Buck D, Thorogood N, Skelly AM. Admission as a dental student to the former UMDS and its relationship to socio-demographic characteristics. Br Dent J 2003; 195:211-7. [PMID: 12970704 DOI: 10.1038/sj.bdj.4810446] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2001] [Accepted: 11/21/2002] [Indexed: 11/09/2022]
Abstract
OBJECTIVES To describe the socio-demographic characteristics of successful and unsuccessful applicants to one UK dental school over a period of five years. To compare the characteristics of successful and unsuccessful candidates. DESIGN Retrospective analysis of admissions data for the former United Medical and Dental Schools of Guy's and St Thomas' (UMDS) dental school provided by Universities and Colleges Admissions Service (UCAS) for a five year period (1994-1998). PARTICIPANTS Applicants to the former UMDS dental school between 1994 and 1998. MAIN OUTCOME MEASURES Success of candidates at four stages of the application process: initial application; offer made by the dental school; offer accepted or declined by the candidate; candidate accepted by the school (post A level results). Comparisons were made of the success rates among candidates grouped according to socio-demographic characteristics at each transition between these stages. A level performance was not included in the analysis, which must limit the findings, and may explain some of the variation found in the study. RESULTS The effect of socio-demographic characteristics on the admissions process was small though significant. Approximately 9% of initial applicants reached the final stage and were accepted into the dental school. The most marked effect was a bias towards female entrants (11.5% of women applicants were accepted, compared with 7% of men). Only 5% of applicants from all the Black minority groups were successful. In comparison 17% of applicants of Chinese origin were successful. The proportion of accepted applicants from London and the South East (12%) was greater than from other areas (9%). CONCLUSIONS Any conclusions must be tempered by the limitations of the study: the retrospective nature of the study together with the lack of information on A level results. Given these caveats, this study has demonstrated that the success of applicants to one former dental school was related to their socio-demographic characteristics. A prospective study including a number of dental schools in the UK which records both predicted and achieved A level grades would provide more definitive information on the impact of socio-demographic factors on admission to dental school.
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Affiliation(s)
- J T Newton
- Department of Dental Public Health & and Oral Health Services Research, GKT Dental Institute, Guy's Hospital, London.
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Abstract
Amorphous silicon electronic portal imaging devices (a-Si EPIDs) allow fast acquisition of high resolution portal images (PI). A visualization of organ movement for adaptive image-guided radiotherapy (IGRT) can be reached by implantation and automatic detection of fiducial markers. A method of automatic detection has been developed for fiducial spherical tungsten markers on PIs, acquired with an a-Si flat-panel imager. The detection method consists of a 2D Mexican hat filter (MHF), whose parameters are tuned to the particular marker signal. The high selectivity of this filter allows a reliable and precise detection of tungsten markers down to a diameter of 1.5 mm. The presented method allows fast, automatic and unsupervised detection of markers. Inevitably, the detection is hampered by image background (bone structures, etc) and noise. A detection success rate higher than 95% was reached, analysing PIs of patients with markers fixed on their skin. Furthermore, this approach to automatic marker detection can also be generalized to elliptic MHFs for the detection of cylindrical markers. The accuracy and detection probability of this method may allow accurate and fast online localization of the considered organ.
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Affiliation(s)
- D Buck
- Abteilung für Medizinische Physik, Universitatsklinik für Radioonkologie Tübingen, Hoppe-Seyler-Str. 3. 72076 Tübingen, Germany
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Deloukas P, Matthews LH, Ashurst J, Burton J, Gilbert JG, Jones M, Stavrides G, Almeida JP, Babbage AK, Bagguley CL, Bailey J, Barlow KF, Bates KN, Beard LM, Beare DM, Beasley OP, Bird CP, Blakey SE, Bridgeman AM, Brown AJ, Buck D, Burrill W, Butler AP, Carder C, Carter NP, Chapman JC, Clamp M, Clark G, Clark LN, Clark SY, Clee CM, Clegg S, Cobley VE, Collier RE, Connor R, Corby NR, Coulson A, Coville GJ, Deadman R, Dhami P, Dunn M, Ellington AG, Frankland JA, Fraser A, French L, Garner P, Grafham DV, Griffiths C, Griffiths MN, Gwilliam R, Hall RE, Hammond S, Harley JL, Heath PD, Ho S, Holden JL, Howden PJ, Huckle E, Hunt AR, Hunt SE, Jekosch K, Johnson CM, Johnson D, Kay MP, Kimberley AM, King A, Knights A, Laird GK, Lawlor S, Lehvaslaiho MH, Leversha M, Lloyd C, Lloyd DM, Lovell JD, Marsh VL, Martin SL, McConnachie LJ, McLay K, McMurray AA, Milne S, Mistry D, Moore MJ, Mullikin JC, Nickerson T, Oliver K, Parker A, Patel R, Pearce TA, Peck AI, Phillimore BJ, Prathalingam SR, Plumb RW, Ramsay H, Rice CM, Ross MT, Scott CE, Sehra HK, Shownkeen R, Sims S, Skuce CD, Smith ML, Soderlund C, Steward CA, Sulston JE, Swann M, Sycamore N, Taylor R, Tee L, Thomas DW, Thorpe A, Tracey A, Tromans AC, Vaudin M, Wall M, Wallis JM, Whitehead SL, Whittaker P, Willey DL, Williams L, Williams SA, Wilming L, Wray PW, Hubbard T, Durbin RM, Bentley DR, Beck S, Rogers J. The DNA sequence and comparative analysis of human chromosome 20. Nature 2001; 414:865-71. [PMID: 11780052 DOI: 10.1038/414865a] [Citation(s) in RCA: 148] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The finished sequence of human chromosome 20 comprises 59,187,298 base pairs (bp) and represents 99.4% of the euchromatic DNA. A single contig of 26 megabases (Mb) spans the entire short arm, and five contigs separated by gaps totalling 320 kb span the long arm of this metacentric chromosome. An additional 234,339 bp of sequence has been determined within the pericentromeric region of the long arm. We annotated 727 genes and 168 pseudogenes in the sequence. About 64% of these genes have a 5' and a 3' untranslated region and a complete open reading frame. Comparative analysis of the sequence of chromosome 20 to whole-genome shotgun-sequence data of two other vertebrates, the mouse Mus musculus and the puffer fish Tetraodon nigroviridis, provides an independent measure of the efficiency of gene annotation, and indicates that this analysis may account for more than 95% of all coding exons and almost all genes.
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Affiliation(s)
- P Deloukas
- The Wellcome Trust Sanger Institute, Hinxton, Cambridge CB10 1SA, UK.
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Kuzirian AM, Epstein HT, Buck D, Child FM, Nelson T, Alkon DL. Pavlovian conditioning-specific increases of the Ca2+- and GTP-binding protein, calexcitin in identified Hermissenda visual cells. J Neurocytol 2001; 30:993-1008. [PMID: 12626881 DOI: 10.1023/a:1021836723609] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Hermissenda CNS, immunolabeled for the memory protein calexcitin showed significant immunostaining over background in the B-photoreceptor cells of the eye. The degree of staining correlated positively with the number of Pavlovian training events experienced by the animals and the degree of Pavlovian conditioning induced. The training regime consisted of exposing animals to light (conditioned stimulus, CS) paired with orbital rotation (unconditioned stimulus, US). In animals that exhibited the conditioned response, calexcitin immunolabeling was more intense than was found for naive (unconditioned) animals or animals given the CS and US in random sequence. Animals exposed to lead (maintained in 1.2 ppm lead acetate) at a dosage known to impair learning in children, showed reduced learning and less intense calexcitin staining whether the CS and US were paired or given randomly. However, the levels were still higher than that of naive animals. Immuno-electron microscopy indicated that the labeling was predominantly within calcium sequestering organelles such as the endoplasmic reticulum, and to lesser extent within mitochondria, and photopigments. The calexcitin density after a short-term memory (STM) regime was the same whether measured 5 minutes after conditioning (when STM was evidenced by foot contraction) or 90 minutes later when no recall was detected. The staining density was also similar to the levels found 5 minutes after long-term memory (LTM) conditioning. However, the LTM regime produced a greater calexcitin intensity at 90 minutes when the memory had been consolidated. This learning-specific increase in calexcitin is consistent with the previously implicated sequence of molecular events that are associated with progressively longer time domains of memory storage.
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Affiliation(s)
- A M Kuzirian
- Marine Biological Laboratory, Woods Hole, MA 02540, USA.
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Newton JT, Buck D, Gibbons DE. Workforce planning in dentistry: the impact of shorter and more varied career patterns. Community Dent Health 2001; 18:236-41. [PMID: 11789702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To compare the frequency and duration of career breaks taken by three groups of dental health care professionals and to assess the impact of these and changes in working hours on human resource planning. BACKGROUND Dental personnel planning has been the subject of recent attention, particularly the role of professionals complementary to dentistry. Data on which to plan a dental personnel strategy have been lacking. METHOD Questionnaire survey of a random sample of 10% of dental practitioners, and of all dental therapists and dental hygienists registered with the General Dental Council. The proportion of each group who had taken a career break at some point during their career was analysed for each professional group. RESULTS A larger proportion of female general dental practitioners (61%) than male practitioners (27%) take a break in their career at some point during their working lives. The proportion of hygienists who take career breaks is similar (57%) to the proportion of female GDPs. The proportion of dental therapists who take a career break (who in this sample were all female) is 71%. The duration of career breaks taken by women is longer than that for males, the median length of career breaks for male dental practitioners is 4 months; female dental practitioners 9 months; hygienists 11 months; therapists 11.5 months. Female GDPs who take a career break can be expected to have a working life 25% shorter than a GDP who does not take a career break. CONCLUSIONS As the proportion of female general dental practitioners increases, and with the possible expansion of the role of professionals complementary to dentistry, there is likely to be an increase in the proportion of dental personnel who take a career break during their working lives. Planning of dental personnel requirements should consider the likely effect of career breaks upon the availability of dental staff.
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Affiliation(s)
- J T Newton
- Division of Dental Public Health and Oral Health Services Research, Guy's King's & St. Thomas' Dental Institute, London, UK
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Buck D, Morris M, Schmidt-Ullrich R, Johnson C, Amir C, Huang D. Quantitation of acute and late toxicities of a concomitant-boost thrice-daily dose escalation radiotherapy regimen for advanced head and neck squamous cell carcinomas. Int J Radiat Oncol Biol Phys 2001. [DOI: 10.1016/s0360-3016(01)02148-4] [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]
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Wagner B, Buck D, Hafner C, Sowka S, Niggemann B, Scheiner O, Breiteneder H. Hev b 7 is a Hevea brasiliensis protein associated with latex allergy in children with spina bifida. J Allergy Clin Immunol 2001; 108:621-7. [PMID: 11590391 DOI: 10.1067/mai.2001.118289] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND In addition to their disease-associated handicaps, patients with spina bifida (SB) are at high risk of developing latex allergy. Individuals with SB represent a special group of latex-allergic patients, inasmuch as their IgE-binding patterns differ from those of other populations of latex-allergic individuals. Two allergens strongly associated with latex allergy in patients with SB--Hev b 1 and Hev b 3--have already been identified. OBJECTIVE We intended to identify a predominant IgE-binding band--in addition to Hev b 1 and 3--at 43 kDa in a study population of 38 latex-allergic (IgE antibodies to latex and symptoms on provocation with latex gloves) and 15 latex-sensitized (IgE antibodies to latex but no symptoms on provocation) children with SB (mean age, 12.3 years) and to determine its frequency of recognition. METHODS Sera of latex-sensitized or latex-allergic patients with SB were tested on latex C extract containing natural Hev b 1, Hev b 3, and Hev b 7 and with the recombinant 43-kDa Hev b 7 in immunoblot and inhibition studies. RESULTS Natural Hev b 1 was recognized by 82% and natural Hev b 3 by 79% of the latex-allergic children with SB. In addition to some other proteins, 15 (39.5%) of 38 latex-allergic and 2 (13%) of 5 latex-sensitized children with SB revealed IgE binding to a 43-kDa band in the latex protein extract. We identified this 43-kDa IgE-binding band as natural Hev b 7 by immunoblotting and inhibition experiments using recombinant Hev b 7. CONCLUSION From these data, we conclude that Hev b 7, the patatin-like Hevea latex protein, is the third SB-associated latex allergen. Future immunotherapy for latex-allergic individuals with SB will have to include Hev b 7 in addition to Hev b 1 and Hev b 3.
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Affiliation(s)
- B Wagner
- Department of Pathophysiology, University of Vienna, Austria
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Abstract
BACKGROUND An important factor determining future health care expenditure is the relationship between ageing, health status and development of age-related disorders such as dementia. AIMS To estimate the formal care costs associated with dementia in England and Wales between 1994 and 2031. METHOD Epidemiological cost model, applied to individuals aged 65 years or over with dementia, using estimates of life expectancy with dementia and dementia-free life expectancy. RESULTS Total costs per year were pound 0.95 billion (men) and pound 5.35 billion (women) using 1994 population estimates. For 2031, costs were pound 2.34 billion and pound 11.20 billion, respectively. Reduced dementia prevalence rates and improvements in mental and physical functioning resulted in lower estimates: pound 1.01 billion (men) and pound 5.77 billion (women), and pound 1.65 billion (men) and pound 7.87 billion (women), respectively. CONCLUSIONS Future increases in the population aged 65 years or over lead to rising formal care costs. However, the magnitude of cost changes depends on assumptions over dementia prevalence and levels of mental and physical functioning.
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Affiliation(s)
- P McNamee
- Department of Epidemiology & Public Health, School of Health Sciences, University of Newcastle, Newcastle-upon-Tyne, UK
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Buck D, Morgan A. Smoking and quitting with the aid of nicotine replacement therapies in the English adult population. Results from the Health Education Monitoring Survey 1995. Eur J Public Health 2001; 11:211-7. [PMID: 11420814 DOI: 10.1093/eurpub/11.2.211] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Many clinical trials have shown the usefulness of nicotine replacement therapies, family physician advice and other cessation aids in enhancing smoking cessation. However, many trials have taken place amongst selected patients and doctors. This paper assesses cessation amongst a representative general adult population in England in order to see whether such aids are as successful amongst more typical smokers. METHODS Descriptive information on the pattern of smoking cessation aids use in the English population is presented for the first time. This is followed by multivariate probit analysis of the 'Health in England 1995' survey data set in order to predict successful smoking cessation as a function of several variables including use of nicotine gum and patches, willpower, advice from family physicians, social class, education, gender, marital status and family composition. RESULTS The results tend to confirm that lower social class and lower educational achievement are linked to continuing smoking status. However, users of nicotine gum and patches were found to be less likely to have given up smoking than non-users. This may be explained by the fact that only those who find it difficult to give up will go to the time and expense of considering such aids. These findings could also be explained by the fact that gum and patches have only been available recently in England. The pattern of results also suggests that 'willpower' is a marker for success in cessation as opposed to a determinant of giving up in its own right. CONCLUSION This research confirms a lot of other research on the determinants of smoking cessation and has for the first time looked at the use and impact of nicotine replacement therapy on giving up in a representative English adult population. More research is needed on observational data sets in order to tease out the true impact of nicotine replacement on cessation rates in representative smoking populations.
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Affiliation(s)
- D Buck
- Department of Dental Public Health & Oral Health Services Research, Guy's, King's and St. Thomas' (GKT) Medical and Dental Institute, King's College London, Guy's Tower, London Bridge, London SE1 9RT, UK.
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Abstract
Bone regeneration promoted by acidic recombinant human fibroblast growth factor (rhFGF-1), rabbit demineralized bone matrix (rDBM), and a fibrin (f) delivery system was measured in critical-sized defects in rabbits' radii. A unilateral segmental defect 20 mm in length was prepared in radii of 48 skeletally mature New Zealand White rabbits divided equally between 4- and 8-week cohorts. The temporal cohorts were divided equally among four treatment groups: rDBM, rDBM/f, rDBM/rhFGF-1/f, and rhFGF-1/f. Data for the fifth group, untreated critical-sized defects, were exploited from previous published reports from this laboratory. In response to experimental treatments, radiomorphometric and histomorphometric methods were used to derive quantitative outcome data that were tested by analysis of variance and post hoc multiple comparison tests (significance p </= 0.05). Radiomorphometric data (percentage of radiopacity of defect) were acquired at the day of the operation and every 2 weeks thereafter, whereas histomorphometric data (square millimeters of new bone formation) were determined at term. The objective for the study was to develop candidate bone regenerative therapies. Therefore, the hypotheses were that experimental treatments would promote bone formation within critical-sized defects and that one treatment would be superior to the rest. Testing hypotheses was achieved with quantitative methodology, and data were subjected to statistical models. Radiopacity at each 2-week period was greater in treated defects than in untreated critical-sized defects. The amount of radiopacity promoted by rDBM/f and rhFGF-1/f at 8 weeks was equivalent and was greater than antecedent times. Histomorphometric data analyses indicated that rDBM/f and rDBM evoked the same quantity of new bone formation at 4 weeks; by 8 weeks, all treatments except rDBM/f had more new bone within the critical-sized defects in comparison to untreated defects. That rDBM/f promoted less new bone than rDBM alone may suggest fibrin decreases bone formation, perhaps by impeding local solubility of endogenous and rDBM-containing signaling molecules. However, rhFGF-1/f promoted a significant and unexpected increase in bone formation response that could refute the previous notion. In conclusion, the combination of rDBM/rhFGF-1/f may represent a significant, new osteogenic therapeutic regimen. Additional assessments in higher order species must be accomplished to corroborate efficacy.
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Affiliation(s)
- D J Mackenzie
- Division of Plastic and Reconstructive Surgery, Oregon Health Sciences University, Portland, Oregan, USA.
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Abstract
The impact of epilepsy on the quality of life of older people with epilepsy has rarely been investigated. As part of a large prevalence study of epilepsy conducted in one UK Health Region, we investigated the burden of their condition in older compared with younger people. A second analysis compared quality of life in those men and women diagnosed after the age of retirement from the workforce compared with those diagnosed before that age. Data were collected from men and women with epilepsy and from their primary and secondary care physicians. There were few differences between older and younger people with regard to their reported quality of life, though younger people were more likely to report feeling stigmatized by their condition. Older people with epilepsy diagnosed in later life were more anxious and depressed than those diagnosed earlier and their overall perception of quality of life was more likely to be negative. Our data emphasize that older people do not necessarily experience poorer quality of life than younger people, but those first diagnosed in later life do appear to have a quality of life which is more impaired. Consideration should be paid to the important psychosocial consequences of epilepsy in the older person.
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Affiliation(s)
- G A Baker
- bakerrThe Walton Centre for Neurology and Neurosurgery, Liverpool, UK.
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