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Patel T, Ni J, Li H, Sharma A, Day T. Management of the Neck in High-Grade Parotid Malignancies: A National Cancer Database Study of 1,541 Patients. Int J Radiat Oncol Biol Phys 2020. [DOI: 10.1016/j.ijrobp.2020.02.572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Cardenas T, Murphy TJ, Kuettner L, Patterson B, Goodwin L, Cluff K, Oertel J, Day T, Edwards S, Hamilton CE, Randolph R, Henderson K, Cowan J, Shin SJ, Bhandarkar S, Kozioziemski BJ. Material Characterization of Hierarchical Tunable Pore Size Polymer Foams Used in the MARBLE Mix Morphology Experiment. Fusion Science and Technology 2020. [DOI: 10.1080/15361055.2020.1790713] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- T. Cardenas
- Los Alamos National Laboratory, SM30 Bikini Atoll Road, Los Alamos, New Mexico 87545
| | - T. J. Murphy
- Los Alamos National Laboratory, SM30 Bikini Atoll Road, Los Alamos, New Mexico 87545
| | - L. Kuettner
- Los Alamos National Laboratory, SM30 Bikini Atoll Road, Los Alamos, New Mexico 87545
| | - B. Patterson
- Los Alamos National Laboratory, SM30 Bikini Atoll Road, Los Alamos, New Mexico 87545
| | - L. Goodwin
- Los Alamos National Laboratory, SM30 Bikini Atoll Road, Los Alamos, New Mexico 87545
| | - K. Cluff
- Los Alamos National Laboratory, SM30 Bikini Atoll Road, Los Alamos, New Mexico 87545
| | - J. Oertel
- Los Alamos National Laboratory, SM30 Bikini Atoll Road, Los Alamos, New Mexico 87545
| | - T. Day
- Los Alamos National Laboratory, SM30 Bikini Atoll Road, Los Alamos, New Mexico 87545
| | - S. Edwards
- Los Alamos National Laboratory, SM30 Bikini Atoll Road, Los Alamos, New Mexico 87545
| | - C. E. Hamilton
- Los Alamos National Laboratory, SM30 Bikini Atoll Road, Los Alamos, New Mexico 87545
| | - R. Randolph
- Los Alamos National Laboratory, SM30 Bikini Atoll Road, Los Alamos, New Mexico 87545
| | - K. Henderson
- Los Alamos National Laboratory, SM30 Bikini Atoll Road, Los Alamos, New Mexico 87545
| | - J. Cowan
- Los Alamos National Laboratory, SM30 Bikini Atoll Road, Los Alamos, New Mexico 87545
| | - S. J. Shin
- Lawrence Livermore National Laboratory, Livermore, California
| | - S. Bhandarkar
- Lawrence Livermore National Laboratory, Livermore, California
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Bird J, Kalker A, Chan J, Rimke A, Chan G, Wilson R, Brutsaert T, Jendzjowsky N, Sherpa M, Day T. Severity of Central Sleep Apnea Does Not Improve Sleeping Oxygen Saturation During Ascent to High Altitude. FASEB J 2020. [DOI: 10.1096/fasebj.2020.34.s1.04468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Pandruvada S, Still M, Goertzen J, Kelly A, Neville B, Huja S, Ogretmen B, Day T. Targeting tyrosine phosphatase SHP2 in oral cancers. FASEB J 2020. [DOI: 10.1096/fasebj.2020.34.s1.03346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Shafer B, Day T, Chan J, Kalker A, Rimke A, Chan G, Saran G, Sands S, Foster G. Apnea-hypopnea index is associated with increased loop gain during sleep at ascending altitudes. Sleep Med 2019. [DOI: 10.1016/j.sleep.2019.11.961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Winkelman T, Hasselmo S, McNaughton K, Day T, Rolison M, Ellison K, Jarzabek E, Lewis B, Wolf J, Baddam S, Canapari C, McAllister T, Naples A, McPartland J. 0840 Children with Autism Demonstrate Atypical Resting EEG Correlates of Sleepiness. Sleep 2018. [DOI: 10.1093/sleep/zsy061.839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- T Winkelman
- Yale University School of Medicine, New Haven, CT
| | - S Hasselmo
- Yale University School of Medicine, New Haven, CT
| | - K McNaughton
- Yale University School of Medicine, New Haven, CT
| | - T Day
- Yale University School of Medicine, New Haven, CT
| | - M Rolison
- Yale University School of Medicine, New Haven, CT
| | - K Ellison
- Yale University School of Medicine, New Haven, CT
| | - E Jarzabek
- Yale University School of Medicine, New Haven, CT
| | - B Lewis
- Yale University School of Medicine, New Haven, CT
| | - J Wolf
- Yale University School of Medicine, New Haven, CT
| | - S Baddam
- Yale University School of Medicine, New Haven, CT
| | - C Canapari
- Yale University School of Medicine, New Haven, CT
| | - T McAllister
- Yale University School of Medicine, New Haven, CT
| | - A Naples
- Yale University School of Medicine, New Haven, CT
| | - J McPartland
- Yale University School of Medicine, New Haven, CT
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Sterba KR, Zapka J, LaPelle N, Garris TK, Buchanan A, Scallion M, Day T. Development of a survivorship needs assessment planning tool for head and neck cancer survivors and their caregivers: a preliminary study. J Cancer Surviv 2017. [PMID: 28639158 DOI: 10.1007/s11764-017-0621-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
PURPOSE The purpose of this study was to characterize primary end-of-treatment challenges in head and neck cancer (HNC) to drive the development of a survivorship needs assessment planning (SNAP) tool and evaluate its acceptability and feasibility. METHODS Using qualitative methods (focus groups, interviews), we identified physical, emotional, and social post-treatment challenges from the perspectives of survivors (N = 17), caregivers (N = 14), and healthcare providers (N = 14) and pretested the SNAP tool. After Advisory Board ratings and consensus, the tool was finalized. RESULTS Survivors, caregivers and clinicians consistently highlighted the importance of assessing symptoms and functional abilities (e.g., dry mouth, speech/swallowing difficulties, weight loss), health behaviors (e.g., smoking, alcohol), emotional concerns (e.g., depression, isolation, nutritional distress), and social challenges (e.g., support, finances). Caregivers were overwhelmed and intensely focused on survivors' nutrition and trach/feeding tube care while clinicians emphasized financial and access concerns. Most participants were enthusiastic about the tool and directed a flexible care plan design due to variability in dyad needs. Over 75% reported high comfort using and navigating questions on a tablet and were in strong agreement that the care plan would help families practically and emotionally. Coordination of survivorship visits with follow-up care was critical to address travel and time barriers. While survivors and clinicians recommended waiting 1-6 months after treatment, caregivers preferred earlier survivorship visits. CONCLUSIONS Results pinpointed optimal end-of-treatment domains for routine assessment and support the feasibility of implementing a SNAP tool in the clinic. IMPLICATIONS FOR CANCER SURVIVORS Capitalizing on technology to direct HNC survivorship care is promising.
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Affiliation(s)
- K R Sterba
- Department of Public Health Sciences, Medical University of South Carolina, 68 President Street MSC 955, Charleston, SC, 29425, USA.
- Hollings Cancer Center, Medical University of South Carolina, Charleston, SC, USA.
| | - J Zapka
- Department of Public Health Sciences, Medical University of South Carolina, 68 President Street MSC 955, Charleston, SC, 29425, USA
- Hollings Cancer Center, Medical University of South Carolina, Charleston, SC, USA
| | - N LaPelle
- Division of Behavioral Medicine, University of Massachusetts Medical School, Amherst, MA, USA
| | - T K Garris
- Hollings Cancer Center, Medical University of South Carolina, Charleston, SC, USA
- Department of Otolaryngology-Head and Neck Surgery, Medical University of South Carolina, Charleston, SC, USA
| | - A Buchanan
- Department of Public Health Sciences, Medical University of South Carolina, 68 President Street MSC 955, Charleston, SC, 29425, USA
- Hollings Cancer Center, Medical University of South Carolina, Charleston, SC, USA
| | - M Scallion
- Department of Public Health Sciences, Medical University of South Carolina, 68 President Street MSC 955, Charleston, SC, 29425, USA
- Hollings Cancer Center, Medical University of South Carolina, Charleston, SC, USA
| | - T Day
- Hollings Cancer Center, Medical University of South Carolina, Charleston, SC, USA
- Department of Otolaryngology-Head and Neck Surgery, Medical University of South Carolina, Charleston, SC, USA
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Borucki R, Nguyen S, Nicolli E, Sridharan S, Day T, Neskey D. Prognostic Significance of Extracapsular Spread and Perineural and Lymphovascular Invasion in Patients with HPV- and Non-HPV–Related Oropharyngeal Squamous Cell Carcinoma. Int J Radiat Oncol Biol Phys 2016. [DOI: 10.1016/j.ijrobp.2015.12.105] [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: 11/24/2022]
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9
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Zhan K, Nicolli E, Day T. Demographics, Disparities, and Survival in Young Patients With Oral Cavity Squamous Cell Carcinoma: A Population-Level Analysis of 3828 Cases. Int J Radiat Oncol Biol Phys 2016. [DOI: 10.1016/j.ijrobp.2015.12.143] [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]
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10
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Zhan K, Khaja S, Huang A, Bell D, Day T. Predictors of Survival in Parotid Adenocarcinoma (Not Otherwise Specified): A National Cancer Data Base Study of 3155 Patients. Int J Radiat Oncol Biol Phys 2016. [DOI: 10.1016/j.ijrobp.2015.12.328] [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: 11/25/2022]
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11
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Loor G, Howard B, Iles T, Mattison L, Meyer P, Day T, Panoskaltsis-Mortari A, Kelly R, Iaizzo P. Prolonged Lung Preservation at 24 Hours Using Donor Whole Blood Perfusion in the Organ Care System (OCS). J Heart Lung Transplant 2015. [DOI: 10.1016/j.healun.2015.01.793] [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: 10/23/2022] Open
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12
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Iliopoulou K, Anderson J, Day T. BEHAVIOURAL INFLUENCES OF CRITICAL CARE PHYSICIANS AND NURSES INTENTION TO IMPLEMENT PREVENTIVE EVIDENCE-BASED MEASURES TOWARDS CENTRAL LINE ASSOCIATED BLOOD STREAM INFECTIONS (CLABSIS). Intensive Care Med Exp 2015. [PMCID: PMC4797494 DOI: 10.1186/2197-425x-3-s1-a890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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13
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Affiliation(s)
- J. Hansen
- Department of Mathematics and Statistics; Jeffery Hall; Queen's University; Kingston ON Canada
| | - T. Day
- Department of Mathematics and Statistics; Jeffery Hall; Queen's University; Kingston ON Canada
- Department of Biology; Queen's University; Kingston ON Canada
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Gill P, Skilton R, Day T, Harding D, Iredale R. 149 The Tenovus nurse-led cancer call back service. Eur J Oncol Nurs 2014. [DOI: 10.1016/s1462-3889(14)70168-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Abstract
The ability of a pathogen to cause an epidemic when introduced in a new host population often relies on its ability to adapt to this new environment. Here, we give a brief overview of recent theoretical and empirical studies of such evolutionary emergence of pathogens. We discuss the effects of several ecological and genetic factors that may affect the likelihood of emergence: migration, life history of the infectious agent, host heterogeneity, and the rate and effects of mutations. We contrast different modelling approaches and indicate how details in the way we model each step of a life cycle can have important consequences on the predicted probability of evolutionary emergence. These different theoretical perspectives yield important insights into optimal surveillance and intervention strategies, which should aim for a reduction in the emergence (and re-emergence) of infectious diseases.
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Affiliation(s)
- S Gandon
- CEFE, CNRS, 1919 route de Mende, Montpellier 34293, France.
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16
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Agbedanu P, No author NA, Brewer M, No author NA, Day T, Kimber M, Anderson K, Rasmussen S, Carlson M. Involvement of a putative intercellular signal-recognizing G protein-coupled receptor in the engulfment of Salmonella by the protozoan Tetrahymena. Open Vet J 2013. [DOI: 10.5455/ovj.2013.v3.i2.p69] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
In an effort to investigate the molecular basis of protozoa engulfment-mediated hypervirulence of Salmonella in cattle, we evaluated protozoan G protein-coupled receptors (GPCRs) as transducers of Salmonella engulfment by the model protozoan Tetrahymena. Our laboratory previously demonstrated that non-pathogenic protozoa (including Tetrahymena) engulf Salmonella and then exacerbate its virulence in cattle, but the mechanistic details of the phenomenon are not fully understood. GPCRs were investigated since these receptors facilitate phagocytosis of particulates by Tetrahymena, and a GPCR apparently modulates bacterial engulfment for the pathogenic protozoan Entamoeba histolytica. A database search identified three putative Tetrahymena GPCRs, based on sequence homologies and predicted transmembrane domains, that were the focus of this study. Salmonella engulfment by Tetrahymena was assessed in the presence of suramin, a non-specific GPCR inhibitor. Salmonella engulfment was also assessed in Tetrahymena in which expression of putative GPCRs was knocked-down using RNAi. A candidate GPCR was then expressed in a heterologous yeast expression system for further characterization. Our results revealed that Tetrahymena were less efficient at engulfing Salmonella in the presence of suramin. Engulfment was reduced concordantly with a reduction in the density of protozoa. RNAi-based studies revealed that knock-down of one the Tetrahymena GPCRs caused diminished engulfment of Salmonella. Tetrahymena lysates activated this receptor in the heterologous expression system. These data demonstrate that the Tetrahymena receptor is a putative GPCR that facilitates bacterial engulfment by Tetrahymena. Activation of the putative GPCR seemed to be related to protozoan cell density, suggesting that its cognate ligand is an intercellular signaling molecule.
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17
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Bonduriansky R, Day T. Nongenetic inheritance and the evolution of costly female preference. J Evol Biol 2012; 26:76-87. [DOI: 10.1111/jeb.12028] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2012] [Revised: 09/23/2012] [Accepted: 09/24/2012] [Indexed: 01/08/2023]
Affiliation(s)
- R. Bonduriansky
- Evolution & Ecology Research Centre; School of Biological, Earth and Environmental Sciences; University of New South Wales; Sydney NSW Australia
| | - T. Day
- Departments of Mathematics and Biology; Queen's University; Kingston ON Canada
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Day T, Li X, Zou X, Ressom H, Kasid U. 509 Transcriptome Analysis Reveals Candidate Genes and Pathways Regulated by TNFAIP8, A NF-kB-inducible Oncogenic Molecule, in Androgen-refractory Metastatic Prostate Cancer Cells. Eur J Cancer 2012. [DOI: 10.1016/s0959-8049(12)72306-7] [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: 11/25/2022]
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Affiliation(s)
- T Day
- Dept of Mathematics and Statistics, Queen's University, Kingston, ON, Canada K7L 3N6
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Abstract
Recent outbreaks of novel infectious diseases (e.g. SARS, influenza H1N1) have highlighted the threat of cross-species pathogen transmission. When first introduced to a population, a pathogen is often poorly adapted to its new host and must evolve in order to escape extinction. Theoretical arguments and empirical studies have suggested various factors to explain why some pathogens emerge and others do not, including host contact structure, pathogen adaptive pathways and mutation rates. Using a multi-type branching process, we model the spread of an introduced pathogen evolving through several strains. Extending previous models, we use a network-based approach to separate host contact patterns from pathogen transmissibility. We also allow for arbitrary adaptive pathways. These generalizations lead to novel predictions regarding the impact of hypothesized risk factors. Pathogen fitness depends on the host population in which it circulates, and the ‘riskiest’ contact distribution and adaptive pathway depend on initial transmissibility. Emergence probability is sensitive to mutation probabilities and number of adaptive steps required, with the possibility of large adaptive steps (e.g. simultaneous point mutations or recombination) having a dramatic effect. In most situations, increasing overall mutation probability increases the risk of emergence; however, notable exceptions arise when deleterious mutations are available.
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Affiliation(s)
- H K Alexander
- Department of Mathematics and Statistics, Queen's University, Kingston, Ontario, Canada.
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22
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Baldovin C, Minnings K, Majury A, Evans G, Day T. P263 Pandemic influenza: a laboratory testing model. Int J Antimicrob Agents 2009. [DOI: 10.1016/s0924-8579(09)70482-0] [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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Abstract
We have used the scanning gate microscopy technique to image scar structures in an open quantum dot, fabricated in an InAs quantum well and defined by electron beam lithography. These are shown to have a periodicity in magnetic field that correlates with that found in the conductance fluctuations. Simulations have shown that these magnetic transform images bear a strong resemblance to actual scars found in the dots.
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Affiliation(s)
- A M Burke
- Department of Electrical Engineering and Center for Solid State Electronics Research, Arizona State University, Tempe, AZ 85287-5706, USA
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Needham M, Scott A, Christiansen F, James I, Corbett A, Day T, Kiers L, Laing N, Allcock R, Mastaglia F. G.P.5.06 HLA alleles and MHC haplotypes in sporadic inclusion body myositis: Frequencies and phenotypic correlations. Neuromuscul Disord 2008. [DOI: 10.1016/j.nmd.2008.06.162] [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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Needham M, James I, Corbett A, Day T, Christiansen F, Phillips B, Mastaglia FL. Sporadic inclusion body myositis: phenotypic variability and influence of HLA-DR3 in a cohort of 57 Australian cases. J Neurol Neurosurg Psychiatry 2008; 79:1056-60. [PMID: 18258695 DOI: 10.1136/jnnp.2007.138891] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND AND AIMS There have been few studies of the variability in the clinical phenotype in sporadic inclusion body myositis (sIBM) and it is not known whether the human leucocyte antigen (HLA) haplotype influences the phenotype and course of the disease. We studied a large cohort of patients with sIBM in order to determine the degree of phenotypic variability and different modes of presentation, as well as the influence of HLA haplotypes. METHOD A cross-sectional study of 57 biopsy-proven sIBM cases from three Australian centres was performed. Patients were interviewed and examined by a single investigator, and had HLA typing and autoantibody studies. RESULTS Although the initial symptoms in the majority of cases were attributable to quadriceps weakness (79%), a proportion of patients presented due to finger weakness (12%), foot drop (7%) or dysphagia (1.8%). Although the majority had the classic combination of quadriceps and forearm muscle involvement, some patients had predominantly forearm weakness with sparing of the quadriceps, or severe involvement of the anterior tibial muscles. Asymmetrical involvement was common (82%), particularly of the forearm muscles, with the non-dominant side being more severely affected in most cases. Carriage of the HLA-DRB1*0301 (DR3) allele was associated with lower quadriceps muscle strength and a more rapid decline in strength. CONCLUSIONS The findings emphasise the variability in the mode of presentation, patterns of muscle involvement and clinical course of sIBM in this population, and indicate that the HLA-DRB1*0301 (DR3) allele may influence the rate of progression as well as susceptibility to the disease.
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Affiliation(s)
- M Needham
- Centre for Neuromuscular and Neurological Disorders, University of Western Australia, Australian Neuromuscular Research Institute (ANRI), Queen Elizabeth II Medical Centre, Nedlands, Perth 6009, WA, Australia.
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Abstract
The description of coevolutionary dynamics requires a characterization of the evolutionary dynamics of both the parasite and its host. However, a thorough description of the underlying genetics of the coevolutionary process is often extremely difficult to carry out. We propose that measures of adaptation (mean population fitness) across time or space may represent a feasible alternative approach for characterizing important features of the coevolutionary process. We discuss recent experimental work in the light of simple mathematical models of coevolution to demonstrate the potential power of this phenotypic experimental approach.
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Affiliation(s)
- S Gandon
- Centre d'Ecologie Fonctionnelle et Evolutive, Montpellier, France.
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27
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Needham M, Corbett A, Day T, Fabian V, Mastaglia F. G.P.13.07 Prevalence and diagnosis of sporadic inclusion body myositis (sIBM) in Western Australia. Neuromuscul Disord 2007. [DOI: 10.1016/j.nmd.2007.06.299] [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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28
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Needham M, Corbett A, Day T, Mastaglia F. G.P.13.06 Sporadic inclusion body myositis (sIBM): A phenotypic spectrum in a cohort of 57 cases. Neuromuscul Disord 2007. [DOI: 10.1016/j.nmd.2007.06.298] [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]
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29
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Prasad NG, Bedhomme S, Day T, Chippindale AK. An evolutionary cost of separate genders revealed by male-limited evolution. Am Nat 2006; 169:29-37. [PMID: 17206582 DOI: 10.1086/509941] [Citation(s) in RCA: 148] [Impact Index Per Article: 8.2] [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: 06/13/2006] [Accepted: 08/28/2006] [Indexed: 11/03/2022]
Abstract
Theory predicts that intralocus sexual conflict can constrain the evolution of sexual dimorphism, preventing each sex from independently maximizing its fitness. To test this idea, we limited genome-wide gene expression to males in four replicate Drosophila melanogaster populations, removing female-specific selection. Over 25 generations, male fitness increased markedly, as sexually dimorphic traits evolved in the male direction. When male-evolved genomes were expressed in females, their fitness displayed a nearly symmetrical decrease. These results suggest that intralocus conflict strongly limits sex-specific adaptation, promoting the maintenance of genetic variation for fitness. Populations may carry a heavy genetic load as a result of selection for separate genders.
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Affiliation(s)
- N G Prasad
- Department of Biology, Queen's University at Kingston, Biosciences Complex, 116 Barrie Street, Ontario K7L 3N6, Canada.
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Bond CE, Patel P, Crouch L, Tetlow N, Day T, Abu-Hayyeh S, Williamson C, Greenfield SA. Astroglia up-regulate transcription and secretion of 'readthrough' acetylcholinesterase following oxidative stress. Eur J Neurosci 2006; 24:381-6. [PMID: 16903848 DOI: 10.1111/j.1460-9568.2006.04898.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [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: 11/27/2022]
Abstract
Novel and diverse functions of glial cells are currently the focus of much attention [A. Volterra and J. Meldolesi (2005) Nature Rev. 6, 626-640]. Here we present evidence that rat astroglia release acetylcholinesterase (AChE) as part of their response to hypoxic damage. Exposure of astroglia to tert-butyl hydroperoxide, and hence oxidative stress, subsequently leads to a switching in mRNA from the classical membrane-bound T-AChE to a preferential increase in the splice variant for a soluble form, R-AChE, This change in expression is reflected in increased perinuclear and reduced cytoplasmic AChE staining of the insulted glial cells, with a concomitant and marked increase in extracellular secretion that peaks at 1 h post-treatment. An analogous increase in R-AChE, over a similar time scale, occurs in response to psychological stress [D. Kaufer et al. (1998) Nature 93, 373-377], as well as to head injury and stroke [E. Shohami et al. (1999) J. Neurotrauma 6, 365-76]. The data presented here suggest that glial cells may be key chemical intermediaries in such situations and, perhaps more generally in pathological conditions involving oxidative stress, such as neurodegeneration.
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Affiliation(s)
- C E Bond
- University Department of Pharmacology, Mansfield Road, Oxford OX1 3QT, UK.
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Sawhney R, Dragun A, Stuart RK, Chaudhary UB, Day T, Gillespie MB, Sharma A. Concurrent split course hyperfractionated radiotherapy (Hfx RT) with biweekly cisplatin (DDP) and paclitaxel (P) in patients with recurrent, previously irradiated squamous cell carcinoma of the head and neck (SCCHN): The MUSC experience. J Clin Oncol 2006. [DOI: 10.1200/jco.2006.24.18_suppl.5578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
5578 Background: Locally recurrent disease (RD) contributes to the majority of SCCHN-related deaths. In addition, second primary tumors (SPT) develop in approximately 30% of patients (pts) who were cured of their primary malignancy. For pts with disease (RD or SPT) in a previously irradiated region, therapeutic options are limited. Approaches utilizing reirradiation with concurrent chemotherapy (CT) have been investigated, with promising initial results. We retrospectively report the clinical outcome & toxicity of such a regimen. Methods: A cohort of pts with locally recurrent or second primary SCCHN within previous radiation portals were treated with concurrent chemoradiotherapy (CRT). Pts received HFx RT (1.5 Gy/Fx BID × 5 every 2 wks × 4), in combination with DDP 15 mg/m2 IV QD × 5 and P 20 mg/m2 IV QD × 5 q 2 wks × 4. Filgrastim was given on days 6–13 of each 2 wk cycle. Results: Nineteen pts were treated (median age 61; 84% with RD at median of 22 mos, 16% SPT; primary site: oropharynx-32%, larynx-32%, oral cavity 21%). Two pts had treatment discontinued early (due to hemoptysis & declining performance status, respectively). Seventeen pts were evaluable at a median f/u of 13 mos. Acute skin & mucous membrane toxicity (Grade ≥ 2) was seen in 11% and 5% of pt’s, respectively, and 32% of pts developed skin fibrosis as a late radiation toxicity. Most pts (82%) received all 4 scheduled cycles of CT. Grade ≥ 3 hematologic toxicity occurred in 29% of pts (anemia 24%, neutropenia 24%, & thrombocytopenia 12%). Infection was the primary non-hematologic toxicity, with Grade ≥ 3 infection in 29% (4 pneumonia, 1 vascular catheter). There was 1 treatment-related death (hypotension with CVA). Of the 16 pts who completed treatment, 4 had initial surgery, and thus had no measurable disease upon commencing CRT. Objective responses to CRT were noted in all of the remaining 12 pts and 50% achieved a CR. One-year OS rate was 65%, with median survival not yet reached. Conclusions: RD and SPT pts who are not surgical candidates have limited treatment options. Aggressive reirradiation with biweekly CT produces excellent response rates, with acceptable local and systemic toxicities. No significant financial relationships to disclose.
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Affiliation(s)
- R. Sawhney
- Medical University of South Carolina, Charleston, SC
| | - A. Dragun
- Medical University of South Carolina, Charleston, SC
| | - R. K. Stuart
- Medical University of South Carolina, Charleston, SC
| | | | - T. Day
- Medical University of South Carolina, Charleston, SC
| | | | - A. Sharma
- Medical University of South Carolina, Charleston, SC
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Norris JS, Bielawska A, Day T, El-Zawahri A, ElOjeimy S, Hannun Y, Holman D, Hyer M, Landon C, Lowe S, Dong JY, McKillop J, Norris K, Obeid L, Rubinchik S, Tavassoli M, Tomlinson S, Voelkel-Johnson C, Liu X. Combined therapeutic use of AdGFPFasL and small molecule inhibitors of ceramide metabolism in prostate and head and neck cancers: a status report. Cancer Gene Ther 2006; 13:1045-51. [PMID: 16763610 DOI: 10.1038/sj.cgt.7700965] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
As of January 2005, there were 1020 gene therapy clinical trials ongoing worldwide with 675 or 66.2% devoted to cancer gene therapy. The majority are occurring in the US and Europe (http://www.wiley.co.uk/genetherapy/clinical/). At the present time, to our knowledge there are no trials that employ gene delivery of Fas Ligand (FasL). As an important note, and in contrast to somatic cell therapy trials, there are no reported deaths due to therapeutic vector administration in any cancer gene therapy trial. That said, from our studies and from the published literature, the issue of gene delivery remains the major obstacle to successfully employing gene therapy for cancer treatment. Numerous laboratories are studying this with many different approaches. My co-workers and I have focused on the delivery issue by using various approaches that address tumor targeting and transgene expression. In addition, we are focusing on enhancing tumor cell killing via the bystander effect and through use of small molecules to enhance bystander activity.
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Affiliation(s)
- J S Norris
- Department of Microbiology, Medical University of South Carolina (MUSC), Charleston, SC 29425, USA.
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33
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Lawson AK, Lichtenberger M, Day T, Ko J, Kirby R. Comparison of sevoflurane and isoflurane in domestic ferrets (Mustela putorius furo). Vet Ther 2006; 7:207-12. [PMID: 17039443] [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: 05/12/2023]
Abstract
Isoflurane anesthesia is commonly used in ferrets for routine examinations and diagnostics. Sevoflurane is now being used as well, but there have been no studies to date directly comparing these agents in domestic ferrets. A prospective study was designed to evaluate the quality and speed of anesthetic induction and recovery using isoflurane and sevoflurane in ferrets. In addition effects on heart rate, blood pressure and packed cell volume were also recorded. No significant differences were noted between anesthetic agents.
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Affiliation(s)
- A K Lawson
- Puget Sound Veterinary Referral Center, 5608 South Durango, Tacoma, WA 98409, USA
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34
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Baillie C, McLeang L, Mulroy L, Day T. 148 How do lung cancer patients experience others' attitudes about lung cancer? Radiother Oncol 2005. [DOI: 10.1016/s0167-8140(05)80309-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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35
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Day T. Research and practice. Intensive Crit Care Nurs 2004. [DOI: 10.1016/j.iccn.2004.02.003] [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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36
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Abstract
AIM The aim of the present study was to demonstrate acute, local vasodilatatory effects of insulin and C-peptide on cutaneous microvascular function in Type 1 diabetic subjects. There are no published data available examining physiological effects of C-peptide delivered in this way. METHODS The study included 20 participants with C-peptide-deficient Type 1 diabetes mellitus. Cutaneous microvascular function was assessed on the forearm using laser Doppler velocimetry. Insulin, C-peptide, acetylcholine (ACh), sodium nitroprusside (SNP) and saline were delivered through the skin using iontophoresis. The response was measured as percentage increase in flux above baseline. RESULTS C-peptide delivered by iontophoresis produced a vasodilatatory response greater than the response to saline (289.5 +/- 265.9% vs. 105.1 +/- 163.6%, P = 0.003). The response to C-peptide was also shown to be dose dependent. Further, the size of the response to C-peptide correlated well with the size of the response to the endothelium-dependent vasodilatator ACh (r = 0.666, P = 0.001) but not with the size of the response to the endothelium-independent vasodilator SNP (r = 0.345, P > 0.05). CONCLUSIONS Physiological effects of C-peptide on cutaneous microvascular function could be demonstrated in individuals with Type 1 diabetes. The results support both physiological activity of C-peptide and an endothelium-dependent mechanism similar to that of ACh. The technique reported may be useful in investigating vasoactive actions of C-peptide in a safe and non-invasive way.
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Affiliation(s)
- C Delaney
- International Diabetes Institute, 250 Kooyong Road, Caulfield, Victoria 3162, Australia.
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37
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Day T, Greenfield SA. Bioactivity of a peptide derived from acetylcholinesterase in hippocampal organotypic cultures. Exp Brain Res 2004; 155:500-8. [PMID: 14685807 DOI: 10.1007/s00221-003-1757-1] [Citation(s) in RCA: 29] [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] [Received: 02/04/2003] [Accepted: 10/22/2003] [Indexed: 10/26/2022]
Abstract
While the molecular basis underlying the non-classical actions of acetylcholinesterase (AChE) is presently unknown, a candidate peptide sequence located at the C-terminus of AChE (AChE-peptide) has recently been identified. This study explored the bioactivity of synthetic AChE-peptide using in vitro organotypic cultures of rat hippocampus. Neurotrophic effects, detected as increased neurite outgrowth from MAP-immunopositive neurones, were apparent using 1 h exposure to 1-10 nM AChE-peptide. As exposure time increased, cell death occurred as indicated by TdT-mediated dUTP biotin nick-end labelling (TUNEL). This process was accelerated at higher AChE-peptide concentrations, with lactate dehydrogenase (LDH) efflux observed following prolonged exposure to 1-10 microM AChE-peptide. Apoptotic cells were detected by Hoechst 33342 staining following 24 h application of 10 nM AChE-peptide. However, propidium iodide reactivity revealed a simultaneous loss of membrane integrity indicative of necrosis, suggesting that AChE-peptide induces cell death via a continuum of apoptotic and necrotic processes. Prolonged exposure to AChE-peptide also resulted in a concentration-dependent reduction in neurite outgrowth from MAP2-positive neurons, although immunohistochemical studies provided some evidence of differential responsiveness in GABAergic, cholinergic and somatostatin neurones. In addition, bioactivity was sequence specific since a scrambled AChE-peptide analogue, as well as the corresponding BuChE-peptide, was ineffective. In conclusion, the bioactivity associated with the AChE-peptide sequence may account for the non-cholinergic actions of AChE, whilst its neurotrophic-apoptotic-necrotic spectrum of action may be involved in the aetiology of neurodegenerative disorders such as Alzheimer's disease.
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Affiliation(s)
- T Day
- University of Oxford, Department of Pharmacology, Mansfield Road, Oxford, OX1 3QT, UK
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38
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Day T, Greenfield SA. A peptide derived from acetylcholinesterase induces neuronal cell death: characterisation of possible mechanisms. Exp Brain Res 2003; 153:334-42. [PMID: 13680041 DOI: 10.1007/s00221-003-1567-5] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2003] [Accepted: 06/17/2003] [Indexed: 11/29/2022]
Abstract
Acetylcholinesterase (AChE) exhibits functions unrelated to the catalysis of acetylcholine (ACh) in particular during development. Although the underlying mechanism(s) is presently unknown, a candidate peptide fragment (AChE-peptide) has recently been identified, and been shown to induce a continuum of apoptotic and necrotic neuronal cell death in rat hippocampal organotypic cultures. The aim of this study was to trace the cell death pathway initiated by AChE-peptide. Using specific antagonists, it was possible to track a series of cellular events following application of 1 nM AChE-peptide: NMDA receptor activation, opening of the L-type voltage gated calcium channel, activation of calcium/calmodulin kinase II, generation of reactive oxygen species and caspase activation. Pharmacological interception at any stage of this cascade blocked the effect of 1 nM AChE-peptide on neurite retraction. Lactate dehydrogenase (LDH) release, a marker for cell lysis, was unaffected by 1 nM AChE-peptide. In contrast, cell death induced by 1 mM AChE-peptide, monitored as neurite retraction and increased LDH efflux, was not offset by any drug treatment. These data suggest that nanomolar concentrations of AChE-peptide exhibit pathophysiological activity via an apoptotic pathway that could play an important role in neuronal development and neurodegeneration.
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Affiliation(s)
- T Day
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, UK
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39
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Abstract
Recent work on sexual selection and sexual conflict has explored the influence of indirect effects on the evolution of female mating behaviour. It has been suggested that the importance of these effects has been underestimated and that the influence of indirect effects may actually be of relatively greater significance than direct effects. Additionally, it has also been suggested that all indirect effects, both good genes and sexy son, are qualitatively equivalent. Here a counterpoint to these suggestions is offered. We argue two main points: (1) it is unlikely that indirect effects will commonly outweigh direct effects, and (2) that there are important differences between good genes and sexy son indirect effects that must be recognized. We suggest that acknowledgement of these distinctions will lead to increased understanding of processes operating in both sexual conflict and sexual selection.
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Affiliation(s)
- E Cameron
- Department of Biology, Queen's University, Kingston, Ontario, Canada.
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40
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van der Mei HC, Kamminga-Rasker HJ, de Vries J, Busscher HJ, White DJ, Date R, Day T, White CD, Williams MK. The influence of a hexametaphosphate-containing chewing gum on the wetting ability of salivary conditioning films in vitro and in vivo. J Clin Dent 2003; 14:14-8. [PMID: 12619265] [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: 03/01/2023]
Abstract
OBJECTIVE Adsorbed conditioning films of salivary components on dental enamel surfaces or pellicles form the interface between teeth and the oral environment. The wetting ability of salivary conditioning films dictates biological adhesion phenomena such as plaque formation, calcification and staining, and also influences mouth perception through effects on lubricity. This study assessed the effects of hexametaphosphate release from a chewing gum matrix on the wetting ability of salivary conditioning films in vitro and in vivo. METHODOLOGY Results obtained for hexametaphosphate chewing gum were compared with those produced by hexametaphosphate-containing dentifrice, which has been clinically proven to have efficacy for stain removal and prevention and dental calculus prevention. RESULTS Contact angle assessments revealed that hexametaphosphate dentifrice produced markedly hydrophilic conditioning films in vitro. Hexametaphosphate chewing gums had only minor effects on surface contact angles in vitro. However, in vivo intra-oral contact angle measurements on tooth surfaces in volunteers showed that both hexametaphosphate dentifrice and chewing gum produced more hydrophilic tooth surfaces. CONCLUSION These results support the activity of hexametaphosphate on tooth surfaces delivered both from dentifrice and chewing gum forms.
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Affiliation(s)
- H C van der Mei
- Department of Biomedical Engineering, University of Groningen, Groningen, The Netherlands.
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41
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Day T. Population structure inhibits evolutionary diversification under competition for resources. Genetica 2002; 112-113:71-86. [PMID: 11838788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
A model is presented that explores how population structure affects the evolutionary outcome of ecological competition for resources. The model assumes that competition for resources occurs within groups of a finite number of individuals (interaction groups), and that limited dispersal of individuals between groups (according to Wright's island model of population structure) results in genetic structuring of the population. It is found that both finite-sized interaction groups and limited dispersal can have substantial effects on the evolution of resource exploitation strategies as compared to models with a single, infinitely large, well-mixed interaction group. Both effects, in general, tend to select for less aggressive competitive strategies. Moreover, both effects also tend to reduce the likelihood of the evolutionary diversification of resource exploitation strategies that often occurs in models of resource competition with infinite populations. The results are discussed in the context of theories of the evolutionary diversification of resource exploitation strategies and speciation.
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Affiliation(s)
- T Day
- Department of Zoology, University of Toronto, ON, Canada.
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42
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Abstract
In this study neurite outgrowth from cultured hippocampal neurones was increased by addition of acetylcholinesterase acting in a non-cholinergic manner. Only monomeric acetylcholinesterase, a form of acetylcholinesterase dominant in development, increased neurite outgrowth (3-10 U/ml); moreover this effect was not blocked by active site blockers (echothiophate and galanthamine) but was sensitive to the addition of peripheral site blockers (fasciculin and BW284c51). It appears therefore that acetylcholinesterase has alternative, non-cholinergic functions, one of which could be in development, via a peripheral site. The possibility of a causal relationship between neurite outgrowth and calcium influx was explored using a spectrum of acetylcholinesterase variants, inhibitors and calcium channel blockers. Acetylcholinesterase regulation of outgrowth was shown to depend on an influx of extracellular calcium specifically via the L-type voltage-gated calcium channel. In summary, we propose that, independent of its catalytic activity, a selective form of acetylcholinesterase has a role in the development of hippocampal neurones via a selective voltage-gated calcium channel.
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Affiliation(s)
- T Day
- Department of Pharmacology, University of Oxford, UK.
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43
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Abstract
A mathematical model is presented that explores the relationship between transmission patterns and the evolution of virulence for horizontally transmitted parasites when only a single parasite strain can infect each host. The model is constructed by decomposing parasite transmission into two processes, the rate of contact between hosts and the probability of transmission per contact. These transmission rate components, as well as the total parasite mortality rate, are allowed to vary over the course of an infection. A general evolutionarily stable condition is presented that partitions the effects of virulence on parasite fitness into three components: fecundity benefits, mortality costs, and morbidity costs. This extension of previous theory allows us to explore the evolutionary consequences of a variety of transmission patterns. I then focus attention on a special case in which the parasite density remains approximately constant during an infection, and I demonstrate two important ways in which transmission modes can affect virulence evolution: by imposing different morbidity costs on the parasite and by altering the scheduling of parasite reproduction during an infection. Both are illustrated with examples, including one that examines the hypothesis that vector-borne parasites should be more virulent than non-vector-borne parasites (Ewald 1994). The validity of this hypothesis depends upon the way in which these two effects interact, and it need not hold in general.
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Affiliation(s)
- T Day
- Department of Zoology, University of Toronto, ON, Canada.
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44
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Abstract
A well-known result from the theory of the evolution of virulence is the prediction that the virulence of a pathogen (i.e. the rate of parasite-induced host mortality) always evolves to higher levels when host background mortality rates increase. This prediction, however, is derived from models that assume that host mortality sources combine additively to determine the overall host mortality rate. In this paper, we suggest that such additivity is probably rare for many host-pathogen systems, and explore how the predictions for the evolution of virulence are altered when interactions between host mortality sources are incorporated into the theory. Our results indicate that if mortality-source interactions are sufficiently strong then the evolutionarily stable level of virulence can actually decrease as the background mortality rate increases. Consequently, a detailed mechanistic description of how parasites and other mortality sources combine to cause host mortality is required before reliable predictions about virulence evolution can be made. Moreover, mortality-source interactions make empirical comparisons of the virulence of different parasites a much more subtle issue.
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Affiliation(s)
- P D Williams
- Department of Zoology, University of Toronto, 25 Harbord Street, Toronto, Ontario, Canada M5S 3G5.
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45
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Mastaglia FL, Thickbroom GW, Day T, Bond R. Craniocervical tetanus presenting with dysphagia: diagnostic value of electrophysiological studies. J Neurol 2001; 248:903-4. [PMID: 11697530 DOI: 10.1007/s004150170078] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abstract
Endotracheal suctioning is a frequently performed procedure that has many associated risks and complications. It is imperative that nurses are aware of these risks and are able to practise according to current research recommendations. This study was designed to examine to what extent intensive care nurses' knowledge and practice of endotracheal suctioning is based on research evidence, to investigate the relationships between knowledge and practice, and to evaluate the effectiveness of a research-based teaching programme. This quasi-experimental study was a randomized, controlled, single-blinded comparison of two research-based teaching programmes, with 16 intensive care nurses, using non-participant observation and a self-report questionnaire. Initial baseline data revealed a low level of knowledge for many participants, which was also reflected in practice, as suctioning was performed against many of the research recommendations. Following teaching, significant improvements were seen in both knowledge and practice. Four weeks later these differences were generally sustained, and provide evidence of the effectiveness of the educational intervention. The study raised concern about all aspects of endotracheal suctioning and highlighted the need for changes in nursing practice, with clinical guidelines and focused practice-based education.
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MESH Headings
- Clinical Competence/standards
- Critical Care/methods
- Critical Care/standards
- Education, Nursing, Continuing/methods
- Education, Nursing, Continuing/standards
- Evidence-Based Medicine
- Health Knowledge, Attitudes, Practice
- Humans
- Inservice Training/methods
- Inservice Training/standards
- Intubation, Intratracheal/adverse effects
- Intubation, Intratracheal/nursing
- Nursing Education Research
- Nursing Staff, Hospital/education
- Nursing Staff, Hospital/psychology
- Practice Guidelines as Topic
- Program Evaluation
- Single-Blind Method
- Suction/adverse effects
- Suction/methods
- Suction/nursing
- Suction/standards
- Teaching/methods
- Teaching/standards
- Total Quality Management
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Affiliation(s)
- T Day
- Florence Nightingale School of Nursing and Midwifery, King's College London, UK.
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47
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Abstract
Empirical tests for the importance of population mixing in constraining adaptive divergence have not been well grounded in theory for quantitative traits in spatially discrete populations. We develop quantitative-genetic models to examine the equilibrium difference between two populations that are experiencing different selective regimes and exchanging individuals. These models demonstrate that adaptive divergence is negatively correlated with the rate of population mixing (m, most strongly so when m is low), positively correlated with the difference in phenotypic optima between populations, and positively correlated with the amount of additive genetic variance (G, most strongly so when G is low). The approach to equilibrium is quite rapid (fewer than 50 generations for two populations to evolve 90% of the distance to equilibrium) when either heritability or mixing are not too low (h2 > 0.2 or m > 0.05). The theory can be used to aid empirical tests that: (1) compare observed divergence to that predicted using estimates of population mixing, additive genetic variance/covariance, and selection; (2) test for a negative correlation between population mixing and adaptive divergence across multiple independent population pairs; and (3) experimentally manipulate the rate of mixing. Application of the first two of these approaches to data from two well-studied natural systems suggests that population mixing has constrained adaptive divergence for color patterns in Lake Erie water snakes (Nerodia sipedon), but not for trophic traits in sympatric pairs of benthic and limnetic stickleback (Gasterosteus aculeatus). The theoretical framework we outline should provide an improved basis for future empirical tests of the role of population mixing in adaptive divergence.
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Affiliation(s)
- A P Hendry
- Department of Zoology, University of British Columbia, Vancouver, Canada.
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48
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Buller K, Xu Y, Dayas C, Day T. Dorsal and ventral medullary catecholamine cell groups contribute differentially to systemic interleukin-1beta-induced hypothalamic pituitary adrenal axis responses. Neuroendocrinology 2001; 73:129-38. [PMID: 11244300 DOI: 10.1159/000054629] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Medial parvocellular paraventricular corticotropin-releasing hormone (mPVN CRH) cells are critical in generating hypothalamic-pituitary-adrenal (HPA) axis responses to systemic interleukin-1beta (IL-1beta). However, although it is understood that catecholamine inputs are important in initiating mPVN CRH cell responses to IL-1beta, the contributions of distinct brainstem catecholamine cell groups are not known. We examined the role of nucleus tractus solitarius (NTS) and ventrolateral medulla (VLM) catecholamine cells in the activation of mPVN CRH, hypothalamic oxytocin (OT) and central amygdala cells in response to IL-1beta (1 microg/kg, i.a.). Immunolabelling for the expression of c-fos was used as a marker of neuronal activation in combination with appropriate cytoplasmic phenotypic markers. First we confirmed that PVN 6-hydroxydopamine lesions, which selectively depleted catecholaminergic terminals, significantly reduced IL-1beta-induced mPVN CRH cell activation. The contribution of VLM (A1/C1 cells) versus NTS (A2 cells) catecholamine cells to mPVN CRH cell responses was then examined by placing ibotenic acid lesions in either the VLM or NTS. The precise positioning of these lesions was guided by prior retrograde tracing studies in which we mapped the location of IL-1beta-activated VLM and NTS cells that project to the mPVN. Both VLM and NTS lesions reduced the mPVN CRH and OT cell responses to IL-1beta. Unlike VLM lesions, NTS lesions also suppressed the recruitment of central amygdala neurons. These studies provide novel evidence that both the NTS and VLM catecholamine cells have important, but differential, contributions to the generation of IL-1beta-induced HPA axis responses.
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Affiliation(s)
- K Buller
- Department of Physiology and Pharmacology, University of Queensland, Brisbane, Australia
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49
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50
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Abstract
Models of Fisher's runaway process show that if there is a cost to female preference, no preference or male trait exaggeration will evolve. Surprisingly, this is true no matter how small the cost, which reveals that these models of Fisher's process are structurally unstable (Bulmer 1989). Here a model of Fisher's runaway process is presented to demonstrate that costly female preference evolves very easily when space is explicitly included in the model. The only requirement is that the optimal male phenotype changes across the species' range. The model shows that the spatial average of the female preference and male trait reach an evolutionary equilibrium that is identical to those of nonspatial models, but that the preference and male trait can deviate greatly from these averages at any point in space. For example, if random mating results in the lowest cost to females, then at equilibrium the spatial average preference will be zero. Nevertheless, there will be some locations at which females prefer males with larger ornaments and others where they prefer males with smaller ornaments. Results also show that the structural instability of nonspatial models of Fisher's process is less of a problem in spatial models. In particular, many of the main qualitative features of cost-free spatial models of Fisher's process remain valid even when there are small costs of female preference. Finally, the model shows that abrupt changes in the optimal male phenotype across space can result in an amplification of this pattern when preference has a small cost, but it can also result in a pattern similar to reproductive character displacement. Which of these occurs depends on the magnitude of the cost of female preference. This suggests that some patterns of reproductive character displacement in nature might be explained simply by sexual selection rather than by hybrid dysgenesis and reinforcement.
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Affiliation(s)
- T Day
- Department of Zoology, University of British Columbia, Vancouver, Canada.
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