143 results on '"Fletcher, Rachel"'
Search Results
102. Increasing NAD+ availability in skeletal muscle to augment energy metabolism
- Author
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Fletcher, Rachel, primary, Doig, Craig, additional, Zielinska, Agnieszka, additional, Griffin, Aliesha, additional, Philp, Andrew, additional, and Lavery, Gareth, additional
- Published
- 2015
- Full Text
- View/download PDF
103. New ways for policy makers to interact with citizens through open social network sites - a report on initial results
- Author
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Addis, Matthew, Taylor, Stephen, Fletcher, Rachel, Wilson, Caroline, Fallon, Freddy, Alani, Harith, Mutschke, Peter, and Wandhoefer, Timo
- Abstract
WeGov (www.wegov-project.eu) is a recently started three year project supported by the European Commission to develop new tools that allow policy makers to interact with and understand the opinions of citizens by using well established public social networking sites (facebook, twitter, wordpress etc.). This paper will report initial findings on how to combine and address a range of issues, all of which are critical to success. These include: legal and ethical issues (e.g. privacy, data protection, defamation); risks of using SNS from different stakeholder perspectives including use of technical countermeasures (e.g. pseudo-anonymisation); the research and development of new technologies (e.g. opinion mining and information exchange processes); and most importantly an analysis of what has, and hasn’t worked in the past. All aspects are informing our three planned pilot scenarios and this interdisciplinary, integrated and iterative approach forms the core of the WeGov project.
- Published
- 2010
104. Dynamic Root Rectangles Part Three: Root-Three Rectangles, Palladian Applications
- Author
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Fletcher, Rachel, primary
- Full Text
- View/download PDF
105. Dynamic Root Rectangles Part Two: The Root-Two Rectangle and Design Applications
- Author
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Fletcher, Rachel, primary
- Full Text
- View/download PDF
106. Squaring the Circle: Marriage of Heaven and Earth
- Author
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Fletcher, Rachel, primary
- Full Text
- View/download PDF
107. Proportioning systems in Wirt C. Rowland’s Union Trust Guardian Building
- Author
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Smith, Michael G., primary and Fletcher, Rachel, additional
- Published
- 2014
- Full Text
- View/download PDF
108. A novel modulator of cell invasion and metastasis
- Author
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Watkins, Rachel, primary, Smith, Vicki, additional, Sharna, Neil, additional, Read, Martin, additional, Kwan, Perkin, additional, Fletcher, Rachel, additional, Boelaert, Kristien, additional, Franklyn, Jayne, additional, and McCabe, Chris, additional
- Published
- 2014
- Full Text
- View/download PDF
109. Breaking NAD+: investigating NMRK2 as a regulator of muscle adaptation through NAD+ salvage
- Author
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Doig, Craig, primary, Zielinska, Agnieszka, additional, Fletcher, Rachel, additional, McCabe, Emma, additional, Philp, Andrew, additional, and Lavery, Gareth, additional
- Published
- 2014
- Full Text
- View/download PDF
110. Depletion of glucose-6-phosphate transporter impacts SR calcium homeostasis in muscle
- Author
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Doig, Craig, primary, Zielinska, Agnieszka, additional, Fletcher, Rachel, additional, McCabe, Emma, additional, and Lavery, Gareth, additional
- Published
- 2014
- Full Text
- View/download PDF
111. The Dimensions of Paradise
- Author
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Fletcher, Rachel
- Subjects
The Dimensions of Paradise (Book) -- Book reviews ,Books -- Book reviews ,Anthropology/archeology/folklore ,Philosophy and religion - Published
- 1989
112. The Interplay Between Anxiety and Social Functioning in Williams Syndrome
- Author
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Riby, Deborah M., primary, Hanley, Mary, additional, Kirk, Hannah, additional, Clark, Fiona, additional, Little, Katie, additional, Fleck, Ruth, additional, Janes, Emily, additional, Kelso, Linzi, additional, O’Kane, Fionnuala, additional, Cole-Fletcher, Rachel, additional, Allday, Marianne Hvistendahl, additional, Hocking, Darren, additional, Cornish, Kim, additional, and Rodgers, Jacqui, additional
- Published
- 2013
- Full Text
- View/download PDF
113. Short Reports: How Fruitful is a Face?
- Author
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Cole-Fletcher, Rachel, primary
- Published
- 2011
- Full Text
- View/download PDF
114. Eosinophil-Derived Neurotoxin in Childhood Asthma: Correlation With Disease Severity
- Author
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Kim, Chang-Keun, primary, Callaway, Zak, additional, Fletcher, Rachel, additional, and Koh, Young Yull, additional
- Published
- 2010
- Full Text
- View/download PDF
115. Eero Saarinen’s North Christian Church in Columbus, Indiana
- Author
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Fletcher, Rachel, primary
- Published
- 2010
- Full Text
- View/download PDF
116. Old English Lexicology and Lexicography: Essays in Honor of Antonette diPaolo Healey: edited by Maren Clegg Hyer, Haruko Momma and Samantha Zacher, Cambridge, D. S. Brewer, 2020, 312 pp., £60.00 (hardback)/ £19.99 (ePDF), ISBN: 9781843845614.
- Author
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Fletcher, Rachel
- Subjects
- *
LEXICOLOGY , *NONFICTION - Published
- 2022
- Full Text
- View/download PDF
117. Avoidance, Anxiety, and Sex: The Influence of Romantic Attachment on HIV-Risk among Pregnant Women
- Author
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Kershaw, Trace S., primary, Milan, Stephanie, additional, Westdahl, Claire, additional, Lewis, Jessica, additional, Rising, Sharon Schindler, additional, Fletcher, Rachel, additional, and Ickovics, Jeannette, additional
- Published
- 2006
- Full Text
- View/download PDF
118. Creating critical mass
- Author
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Fletcher, Rachel
- Subjects
Banking, finance and accounting industries ,Business ,Business, international - Abstract
I've been watching the comment around the Lord Davies review and sense a real ambiguity about using compulsion to achieve gender equality on company boards. My instinct is for meritocracy [...]
- Published
- 2011
119. Dating Applications: A Honeypot for Sextortion Victims.
- Author
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Tavakoli, Harmony, Tzani, Calli, Ioannou, Maria, Williams, Thomas James Vaughan, Drouin, Michelle, and Fletcher, Rachel
- Subjects
- *
SOCIAL media , *ONLINE dating , *SUICIDAL ideation , *INTERNET surveys , *EXTORTION , *CYBERBULLYING - Abstract
Perpetrators often have easy access to victims via widely used social media networks, such as Snapchat, Instagram, and Facebook. Nowadays, dating applications have provided one more platform where sextortionists identify potential victims and lure them into extortion and victimization. Limited research and media coverage has revealed that sextortion can cause significant harm, with victims reporting negative psychological consequences, such as depression, anxiety, and suicidal ideation. Many empirical findings arise from explorations of webcam sextortion, with limited literature examining sextortion in social media platforms, and particularly online dating sites. In the current, exploratory study, we examine these modern trends directly via an online survey of 102 participants. Overall, 62.7% had been sextorted by another dating application user, and 25.5% experienced failed attempts of sextortion by another dating application user. Results uniquely showed that Tinder, as well as Snapchat, are often used as fishing platforms for identifying sextortion victims. Furthermore, sextortion could be successfully predicted if individuals perceived that the perpetrator "seemed genuinely interested," demonstrating how online dating platforms which specifically target those seeking romantic connections provide an ideal mechanism for perpetrators to fish for victims. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
120. Pushing the boundary : the periodisation problem in dictionaries of Old English
- Author
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Fletcher, Rachel Ann
- Subjects
- P Philology. Linguistics ; PE English
- Abstract
This thesis offers a detailed study of the theoretical challenge of linguistic periodisation as it appears in dictionaries of Old English, past and present. I consider the varied representations by lexicographers of Old English as a period. I focus especially on how they establish the scope and context of their work by invoking the concept of an imagined period boundary that separates Old English from subsequent periods, and how this boundary is problematised. Five major dictionaries of Old English are used to illustrate developments in historical lexicography from the early stages of Old English scholarship to the present day: William Somner's Dictionarium Saxonico-Latino-Anglicum (1659), Edward Lye and Owen Manning's Dictionarium Saxonico et Gothico-Latinum (1772), Joseph Bosworth's A Dictionary of the Anglo-Saxon Language (1838), Joseph Bosworth and Thomas Northcote Toller's An Anglo-Saxon Dictionary (1882-98 with later supplements), and the University of Toronto's Dictionary of Old English (1986-). Alongside these I also consider relevant material from the Oxford English Dictionary (1884-). The first two chapters of the thesis establish the significance of dictionaries as objects of study that can offer unique insights into the development of linguistic periodisation, and situate them in scholarly history. Chapter Three outlines how lexicographers' interpretations (conscious or otherwise) of periodisation may be reflected in their dictionaries. Chapter Four examines the exact properties and ways of defining the period boundary marking the end of Old English, as it was imagined by different lexicographers. Chapter Five uses case studies of well-known texts associated with late Old English (focusing on the Peterborough Chronicle, the Winteney Rule of Benedict and the Textus Roffensis) to build an account of how the nature of mediæval source texts frequently leads to unavoidable inconsistencies in lexicographical policy. Chapter Six considers how ideal periodisation interacts with external pressures, including the practical methods and aims of lexicography and broader agendas surrounding the portrayal of Old English. The conclusion reflects on significant themes, findings, and identifies future directions for both research and lexicographical practice.
- Published
- 2021
121. Psychological factors leading to sextortion: The role of personality, emotional factors and sexual needs in victimisation.
- Author
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Tzani, Calli, Ioannou, Maria, Fletcher, Rachel, and Williams, Thomas James Vaughan
- Subjects
- *
SEX crimes , *T-test (Statistics) , *HUMAN sexuality , *ATTACHMENT behavior , *INTERNET , *EMOTIONS , *DESCRIPTIVE statistics , *ANXIETY , *CRIME victims , *SURVEYS , *FINANCIAL stress , *SEXUAL harassment , *PERSONALITY , *RESEARCH , *REGRESSION analysis - Abstract
Sextortion often begins with a perpetrator contacting a victim through social media platforms, dating websites, or messaging applications. Victims share their explicit content, allowing the perpetrator to gain control by threatening to expose this material unless demands are met. The limited extant literature on this topic highlights a vast demographic of victims and serious consequences following victimisation. Given its interactional nature, the current, exploratory study examines psychological factors leading to sextortion. Specifically, personality traits, emotional factors, and sexual needs are investigated as predictors of victimisation. These psychological factors have been much neglected in the literature, despite having strong associations with sextortion-related online behaviours. Utilising data from 89 victims (73 males, 16 females; M age = 24.73) and 212 non-victims (42 males, 170 females; M age = 28.55) collected via an online survey, a series of t-tests and regressions were conducted to examine the objectives. Results showed that conscientiousness and emotionality were negatively predictive, and attachment-related anxiety and need for sex were positively predictive of victimisation. A comprehensive model containing these predictors correctly classified 76.1% of cases, indicating potential to measure psychological vulnerability to financial sextortion. With the majority of respondent victims being adult men experiencing financial demands, the discussion details the implications of this research on this group in particular, as well as study limitations. • Identifies who is most vulnerable to sextortion cybercrime. • Personality traits create risk of sextortion victimisation. • Attachment-related anxiety positively predictive of sextortion. • Sexting and need for sex linked to sextortion risk. • Model using psychological predictors of sextortion risk. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
122. Shifting baselines clarify the impact of contemporary logging on forest‐dependent threatened species.
- Author
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Ward, Michelle, Ashman, Kita, Lindenmayer, David B., Legge, Sarah, Kindler, Gareth, Cadman, Timothy, Fletcher, Rachel, Whiterod, Nick, Lintermans, Mark, Zylstra, Philip, Stewart, Romola, Thomas, Hannah, Blanch, Stuart, and Watson, James E. M.
- Subjects
- *
ENVIRONMENTAL degradation , *CLIMATE change mitigation , *ECOLOGICAL integrity , *DEFORESTATION , *ENVIRONMENTAL policy , *POPULATION viability analysis , *ILLEGAL logging - Abstract
Despite the importance of protecting forests and woodlands to achieve global climate and biodiversity goals, logging impacts persist worldwide. Forestry advocates often downplay these impacts but rarely consider the cumulative threat deforestation and degradation has had, and continues to have, on biodiversity. Using New South Wales (Australia) as a case study, we quantify the extent of deforestation and degradation from 1788 (pre‐European colonization) to 2021. We used historical loss as a baseline to evaluate recent logging (2000–2022) and the condition of the remaining native forest and woodland. Condition was quantified by measuring the similarity of a current ecosystem to a historical reference state with high ecological integrity. Using these data, we measured the impacts on 269 threatened terrestrial species. We show that possibly over half (29 million ha) of pre‐1788 native forest and woodland vegetation in NSW has been lost. Of the remaining 25 million ha, 9 million ha is estimated to be degraded. We found recent logging potentially impacted 150 species that had already been affected by this historical deforestation and degradation, but the impacts varied across species. Forty‐three species that were identified as impacted by historical deforestation and degradation and continue to be impacted by logging, now have ≤50% of their pre‐1788 extent remaining that is intact and nine species now have ≤30%. Our research contextualizes the impact of current logging against historical deforestation and highlights deficiencies in environmental assessments that ignore historical baselines. Future land management must consider both the extent and condition of remaining habitat based on pre‐1788 extents. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
123. Delivering Public Value Through Water.
- Author
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Fletcher, Rachel
- Subjects
COVID-19 pandemic ,TARIFF ,ECONOMIC development ,CONTRACTORS ,FINANCE - Published
- 2021
124. Using field hospital simulation to demonstrate changes in completion rates of a UK emergency medical team (EMT) medical record
- Author
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Jafar, Anisa J.N. and Fletcher, Rachel J.
- Abstract
The UK EMT is committed to driving forward the World Health Organisation's (WHO) standards for emergency medical team (EMT) response to sudden onset disasters. Specifically UK EMT have worked on the documentation standards and have designated exercises to focus on this aspect of emergency response.
- Published
- 2020
- Full Text
- View/download PDF
125. Nicotinamide Riboside Augments the Aged Human Skeletal Muscle NAD+ Metabolome and Induces Transcriptomic and Anti-inflammatory Signatures.
- Author
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Elhassan, Yasir S., Kluckova, Katarina, Fletcher, Rachel S., Schmidt, Mark S., Garten, Antje, Doig, Craig L., Cartwright, David M., Oakey, Lucy, Burley, Claire V., Jenkinson, Ned, Wilson, Martin, Lucas, Samuel J.E., Akerman, Ildem, Seabright, Alex, Lai, Yu-Chiang, Tennant, Daniel A., Nightingale, Peter, Wallis, Gareth A., Manolopoulos, Konstantinos N., and Brenner, Charles
- Abstract
Nicotinamide adenine dinucleotide (NAD
+ ) is modulated by conditions of metabolic stress and has been reported to decline with aging in preclinical models, but human data are sparse. Nicotinamide riboside (NR) supplementation ameliorates metabolic dysfunction in rodents. We aimed to establish whether oral NR supplementation in aged participants can increase the skeletal muscle NAD+ metabolome and if it can alter muscle mitochondrial bioenergetics. We supplemented 12 aged men with 1 g NR per day for 21 days in a placebo-controlled, randomized, double-blind, crossover trial. Targeted metabolomics showed that NR elevated the muscle NAD+ metabolome, evident by increased nicotinic acid adenine dinucleotide and nicotinamide clearance products. Muscle RNA sequencing revealed NR-mediated downregulation of energy metabolism and mitochondria pathways, without altering mitochondrial bioenergetics. NR also depressed levels of circulating inflammatory cytokines. Our data establish that oral NR is available to aged human muscle and identify anti-inflammatory effects of NR. • NR supplementation in aged subjects augments the skeletal muscle NAD+ metabolome • NR supplementation does not affect skeletal muscle mitochondrial bioenergetics • NR supplementation reduces levels of circulating inflammatory cytokines Elhassan et al. show that oral nicotinamide riboside increases the NAD+ metabolome in aged human skeletal muscle, without apparently altering mitochondrial bioenergetics. Measures of muscle and whole-body metabolism are also unchanged. Nicotinamide riboside reduces the levels of circulating inflammatory cytokines. Studies in relevant human disease models are warranted. [ABSTRACT FROM AUTHOR]- Published
- 2019
- Full Text
- View/download PDF
126. Additional file 1 of Induction of the nicotinamide riboside kinase NAD+ salvage pathway in a model of sarcoplasmic reticulum dysfunction
- Author
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Doig, Craig, Zielinska, Agnieszka, Fletcher, Rachel, Oakey, Lucy, Elhassan, Yasir, Garten, Antje, Cartwright, David, Heising, Silke, Alsheri, Ahmed, Watson, David, Prehn, Cornelia, Adamski, Jerzy, Tennant, Daniel, and Lavery, Gareth
- Subjects
3. Good health - Abstract
Additional file 1: Figure S1. Acylcarnitine levels of WT and H6PDKO in skeletal muscle, serum and liver. Metabolite signals are presented as Log2 signal intensity.
127. Additional file 1 of Induction of the nicotinamide riboside kinase NAD+ salvage pathway in a model of sarcoplasmic reticulum dysfunction
- Author
-
Doig, Craig, Zielinska, Agnieszka, Fletcher, Rachel, Oakey, Lucy, Elhassan, Yasir, Garten, Antje, Cartwright, David, Heising, Silke, Alsheri, Ahmed, Watson, David, Prehn, Cornelia, Adamski, Jerzy, Tennant, Daniel, and Lavery, Gareth
- Subjects
3. Good health - Abstract
Additional file 1: Figure S1. Acylcarnitine levels of WT and H6PDKO in skeletal muscle, serum and liver. Metabolite signals are presented as Log2 signal intensity.
128. Pushing the boundary: the periodisation problem in dictionaries of Old English
- Author
-
Fletcher, Rachel Ann and Fletcher, Rachel Ann
- Abstract
This thesis offers a detailed study of the theoretical challenge of linguistic periodisation as it appears in dictionaries of Old English, past and present. I consider the varied representations by lexicographers of Old English as a period. I focus especially on how they establish the scope and context of their work by invoking the concept of an imagined period boundary that separates Old English from subsequent periods, and how this boundary is problematised. Five major dictionaries of Old English are used to illustrate developments in historical lexicography from the early stages of Old English scholarship to the present day: William Somner’s Dictionarium Saxonico-Latino-Anglicum (1659), Edward Lye and Owen Manning’s Dictionarium Saxonico et Gothico-Latinum (1772), Joseph Bosworth’s A Dictionary of the Anglo-Saxon Language (1838), Joseph Bosworth and Thomas Northcote Toller’s An Anglo-Saxon Dictionary (1882–98 with later supplements), and the University of Toronto’s Dictionary of Old English (1986–). Alongside these I also consider relevant material from the Oxford English Dictionary (1884–). The first two chapters of the thesis establish the significance of dictionaries as objects of study that can offer unique insights into the development of linguistic periodisation, and situate them in scholarly history. Chapter Three outlines how lexicographers’ interpretations (conscious or otherwise) of periodisation may be reflected in their dictionaries. Chapter Four examines the exact properties and ways of defining the period boundary marking the end of Old English, as it was imagined by different lexicographers. Chapter Five uses case studies of well-known texts associated with late Old English (focusing on the Peterborough Chronicle, the Winteney Rule of Benedict and the Textus Roffensis) to build an account of how the nature of mediæval source texts frequently leads to unavoidable inconsistencies in lexicographical policy. Chapter Six considers how ideal periodisatio
129. Pushing the boundary: the periodisation problem in dictionaries of Old English
- Author
-
Fletcher, Rachel Ann and Fletcher, Rachel Ann
- Abstract
This thesis offers a detailed study of the theoretical challenge of linguistic periodisation as it appears in dictionaries of Old English, past and present. I consider the varied representations by lexicographers of Old English as a period. I focus especially on how they establish the scope and context of their work by invoking the concept of an imagined period boundary that separates Old English from subsequent periods, and how this boundary is problematised. Five major dictionaries of Old English are used to illustrate developments in historical lexicography from the early stages of Old English scholarship to the present day: William Somner’s Dictionarium Saxonico-Latino-Anglicum (1659), Edward Lye and Owen Manning’s Dictionarium Saxonico et Gothico-Latinum (1772), Joseph Bosworth’s A Dictionary of the Anglo-Saxon Language (1838), Joseph Bosworth and Thomas Northcote Toller’s An Anglo-Saxon Dictionary (1882–98 with later supplements), and the University of Toronto’s Dictionary of Old English (1986–). Alongside these I also consider relevant material from the Oxford English Dictionary (1884–). The first two chapters of the thesis establish the significance of dictionaries as objects of study that can offer unique insights into the development of linguistic periodisation, and situate them in scholarly history. Chapter Three outlines how lexicographers’ interpretations (conscious or otherwise) of periodisation may be reflected in their dictionaries. Chapter Four examines the exact properties and ways of defining the period boundary marking the end of Old English, as it was imagined by different lexicographers. Chapter Five uses case studies of well-known texts associated with late Old English (focusing on the Peterborough Chronicle, the Winteney Rule of Benedict and the Textus Roffensis) to build an account of how the nature of mediæval source texts frequently leads to unavoidable inconsistencies in lexicographical policy. Chapter Six considers how ideal periodisatio
130. Pushing the boundary: the periodisation problem in dictionaries of Old English
- Author
-
Fletcher, Rachel Ann and Fletcher, Rachel Ann
- Abstract
This thesis offers a detailed study of the theoretical challenge of linguistic periodisation as it appears in dictionaries of Old English, past and present. I consider the varied representations by lexicographers of Old English as a period. I focus especially on how they establish the scope and context of their work by invoking the concept of an imagined period boundary that separates Old English from subsequent periods, and how this boundary is problematised. Five major dictionaries of Old English are used to illustrate developments in historical lexicography from the early stages of Old English scholarship to the present day: William Somner’s Dictionarium Saxonico-Latino-Anglicum (1659), Edward Lye and Owen Manning’s Dictionarium Saxonico et Gothico-Latinum (1772), Joseph Bosworth’s A Dictionary of the Anglo-Saxon Language (1838), Joseph Bosworth and Thomas Northcote Toller’s An Anglo-Saxon Dictionary (1882–98 with later supplements), and the University of Toronto’s Dictionary of Old English (1986–). Alongside these I also consider relevant material from the Oxford English Dictionary (1884–). The first two chapters of the thesis establish the significance of dictionaries as objects of study that can offer unique insights into the development of linguistic periodisation, and situate them in scholarly history. Chapter Three outlines how lexicographers’ interpretations (conscious or otherwise) of periodisation may be reflected in their dictionaries. Chapter Four examines the exact properties and ways of defining the period boundary marking the end of Old English, as it was imagined by different lexicographers. Chapter Five uses case studies of well-known texts associated with late Old English (focusing on the Peterborough Chronicle, the Winteney Rule of Benedict and the Textus Roffensis) to build an account of how the nature of mediæval source texts frequently leads to unavoidable inconsistencies in lexicographical policy. Chapter Six considers how ideal periodisatio
131. William Somner’s Dictionarium Saxonico-Latino-Anglicum: method, function and legacy
- Author
-
Fletcher, Rachel Ann and Fletcher, Rachel Ann
- Abstract
William Somner’s Dictionarium Saxonico-Latino-Anglicum was the first published dictionary of Old English, appearing in 1659. This thesis investigates the Dictionarium both as a work in itself and as an important representative of early Old English scholarship. Particular attention is paid to how the content and design of the Dictionarium provide information about the methods used in its compilation, and to how these methods reflect the interests and priorities of Somner and his contemporaries in the study of Old English. However, the Dictionarium was not alone in being shaped by such interests and priorities; in its role as a work of reference, it was also in a position to transmit them to its users through the picture of Old English it presented to them. Accordingly, the thesis considers throughout what impression of Old English the content and design of the Dictionarium might have created for its audience, and how its content and function were influenced by Somner’s understanding and intentions regarding who would use his dictionary and for what purpose. All these factors are considered primarily through their influence on the published Dictionarium, but the thesis also deals briefly with the influence of the Dictionarium after its publication. The methodologies selected to address these questions are varied, aiming to cover as many aspects of the Dictionarium as possible in order to better understand it as a whole. For instance, the use in Chapter 1 of a large sample of entries allows the identification of broad themes in Somner’s lexicography, but subsequent chapters use smaller, more targeted samples and individual entries to highlight features of particular interest and reconstruct the unique process of research that went into Somner’s writing of each definition. Findings from these studies are contextualised by chapters dealing with the Dictionarium’s relationship to other studies of Old English and with the significance of the non-lexical material included i
132. William Somner’s Dictionarium Saxonico-Latino-Anglicum: method, function and legacy
- Author
-
Fletcher, Rachel Ann and Fletcher, Rachel Ann
- Abstract
William Somner’s Dictionarium Saxonico-Latino-Anglicum was the first published dictionary of Old English, appearing in 1659. This thesis investigates the Dictionarium both as a work in itself and as an important representative of early Old English scholarship. Particular attention is paid to how the content and design of the Dictionarium provide information about the methods used in its compilation, and to how these methods reflect the interests and priorities of Somner and his contemporaries in the study of Old English. However, the Dictionarium was not alone in being shaped by such interests and priorities; in its role as a work of reference, it was also in a position to transmit them to its users through the picture of Old English it presented to them. Accordingly, the thesis considers throughout what impression of Old English the content and design of the Dictionarium might have created for its audience, and how its content and function were influenced by Somner’s understanding and intentions regarding who would use his dictionary and for what purpose. All these factors are considered primarily through their influence on the published Dictionarium, but the thesis also deals briefly with the influence of the Dictionarium after its publication. The methodologies selected to address these questions are varied, aiming to cover as many aspects of the Dictionarium as possible in order to better understand it as a whole. For instance, the use in Chapter 1 of a large sample of entries allows the identification of broad themes in Somner’s lexicography, but subsequent chapters use smaller, more targeted samples and individual entries to highlight features of particular interest and reconstruct the unique process of research that went into Somner’s writing of each definition. Findings from these studies are contextualised by chapters dealing with the Dictionarium’s relationship to other studies of Old English and with the significance of the non-lexical material included i
133. William Somner’s Dictionarium Saxonico-Latino-Anglicum: method, function and legacy
- Author
-
Fletcher, Rachel Ann and Fletcher, Rachel Ann
- Abstract
William Somner’s Dictionarium Saxonico-Latino-Anglicum was the first published dictionary of Old English, appearing in 1659. This thesis investigates the Dictionarium both as a work in itself and as an important representative of early Old English scholarship. Particular attention is paid to how the content and design of the Dictionarium provide information about the methods used in its compilation, and to how these methods reflect the interests and priorities of Somner and his contemporaries in the study of Old English. However, the Dictionarium was not alone in being shaped by such interests and priorities; in its role as a work of reference, it was also in a position to transmit them to its users through the picture of Old English it presented to them. Accordingly, the thesis considers throughout what impression of Old English the content and design of the Dictionarium might have created for its audience, and how its content and function were influenced by Somner’s understanding and intentions regarding who would use his dictionary and for what purpose. All these factors are considered primarily through their influence on the published Dictionarium, but the thesis also deals briefly with the influence of the Dictionarium after its publication. The methodologies selected to address these questions are varied, aiming to cover as many aspects of the Dictionarium as possible in order to better understand it as a whole. For instance, the use in Chapter 1 of a large sample of entries allows the identification of broad themes in Somner’s lexicography, but subsequent chapters use smaller, more targeted samples and individual entries to highlight features of particular interest and reconstruct the unique process of research that went into Somner’s writing of each definition. Findings from these studies are contextualised by chapters dealing with the Dictionarium’s relationship to other studies of Old English and with the significance of the non-lexical material included i
134. William Somner’s Dictionarium Saxonico-Latino-Anglicum: method, function and legacy
- Author
-
Fletcher, Rachel Ann and Fletcher, Rachel Ann
- Abstract
William Somner’s Dictionarium Saxonico-Latino-Anglicum was the first published dictionary of Old English, appearing in 1659. This thesis investigates the Dictionarium both as a work in itself and as an important representative of early Old English scholarship. Particular attention is paid to how the content and design of the Dictionarium provide information about the methods used in its compilation, and to how these methods reflect the interests and priorities of Somner and his contemporaries in the study of Old English. However, the Dictionarium was not alone in being shaped by such interests and priorities; in its role as a work of reference, it was also in a position to transmit them to its users through the picture of Old English it presented to them. Accordingly, the thesis considers throughout what impression of Old English the content and design of the Dictionarium might have created for its audience, and how its content and function were influenced by Somner’s understanding and intentions regarding who would use his dictionary and for what purpose. All these factors are considered primarily through their influence on the published Dictionarium, but the thesis also deals briefly with the influence of the Dictionarium after its publication. The methodologies selected to address these questions are varied, aiming to cover as many aspects of the Dictionarium as possible in order to better understand it as a whole. For instance, the use in Chapter 1 of a large sample of entries allows the identification of broad themes in Somner’s lexicography, but subsequent chapters use smaller, more targeted samples and individual entries to highlight features of particular interest and reconstruct the unique process of research that went into Somner’s writing of each definition. Findings from these studies are contextualised by chapters dealing with the Dictionarium’s relationship to other studies of Old English and with the significance of the non-lexical material included i
135. The location and effect of aluminium in zeolites
- Author
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Fletcher, Rachel E.
- Subjects
- 546
- Abstract
A systematic DFT study has been carried out to investigate the thermodynamic driving force of Al distribution in zeolites and the effect of Al position on catalytic reactions. Much of this study is concerned with small-pore zeolite SSZ-13, which exhibits a CHA-type framework, although Al distribution is also examined in a range of other zeolite framework-types, including RHO, LTA, ABW, AEI and MOR. Al distribution across framework T-sites was examined in zeolite frameworks at different Si/Al ratios, where Al is compensated by different counter-cation species, including alkali metal cations and protons. The most thermodynamically favourable Al distribution in protonated zeolites was found to be that which violates Löwenstein's rule of Al avoidance. On the contrary, alkali metal-containing frameworks favour Löwenstein Al arrangements, demonstrating the influence of cation identity on Al distribution in zeolites. On investigation of the effect of the organic template on these distributions, it was found that whilst the template has some Al directing ability, in the presence of Na+ and H+ counter-cations the influence of the SDA on Al arrangement is greatly reduced. The diminished influence of the SDA over Al distribution compared to the Na+ and H+ counter-cations is primarily due to sterics and the decreased charge/size ratio of the SDA. Furthermore, introducing water to sodium-containing frameworks screens the charge of the cation, causing Dempsey ordered Al distributions, driven by Al-Al repulsions, to become more thermally accessible in SSZ-13. To examine the distribution of Al throughout the zeolite crystal, SSZ-13 slab structures with (001) and (011) terminating faces were examined. Surface enrichment of Al was found to be favourable in H-SSZ-13 slab structures, whilst well distributed Al was favoured in Na-SSZ-13 structures. Finally, the effect of Al on Mo speciation during methane dehydroaromatisation was examined in Mo/MFI catalysts. The evolution of the catalytically active Mo species was investigated in both silicalite and ZSM-5, these simulations were informed by experiment. Improved binding between the MFI framework and the Mo species was observed in ZSM-5, indicating that the presence of Al is necessary to prevent catalyst deactivation by migration of the active species to the surface of the zeolite.
- Published
- 2019
136. Vitamin B3 salvage and NAD⁺ metabolism in skeletal muscle
- Author
-
Fletcher, Rachel
- Subjects
- 572, QH301 Biology
- Abstract
Nicotinamide adenine dinucleotide (NAD⁺)) is both an essential redox coenzyme and a substrate for NAD⁺ consuming enzymes, such as the sirtuins, which adapt transcriptional programmes to increase energy availability. Skeletal muscle is a major regulator of energy metabolism and its function is impaired with ageing. Uncovering the key routes regulating NAD⁺ availability may provide valuable insight into novel aspects of skeletal muscle metabolic health. Data presented here identifies a limited set of enzymes important for skeletal muscle NAD⁺ -biosynthesis namely; nicotinamide phosphoribosyltransferase (NAMPT) and nicotinamide riboside kinases (NMRK) 1 and 2, which salvage vitamin B3s nicotinamide (NAM) and nicotinamide riboside (NR) to NAD⁺. NAMPT was confirmed vital for recycling of NAM, with NAD+ depleted in myotubes following NAMPT inhibition. Single and double NMRK knockout mouse models found NMRK activity nonessential for maintaining basal NAD⁺, with activity restricted by NR availability. Exogenous NR delivery enhanced NAD⁺ and recovered the effects of NAD⁺ depletion following NAMPT inhibition. NMRK2 was determined highly muscle-specific; although energy signalling was mostly unperturbed in NMRK2KOs, in vivo data indicated impaired metabolic flexibility following high fat diet. While the muscle-specific role of NMRK2 requires further investigation, this thesis identifies NMRK1/2 as important therapeutic targets for enhancing NAD⁺ by NR supplementation.
- Published
- 2017
137. MAIL CALL.
- Author
-
Bannert, Kelli, Birkby-Vance, Michele, Fletcher, Rachel, Ott, Diane, Hall, Suzanne, and Lowe, Marla
- Subjects
LETTERS to the editor ,EQUESTRIANISM ,HORSEMEN & horsewomen ,HORSE sports - Abstract
Several letters to the editor are presented in response to articles in the previous issues including "The Thief of Time," in the April 2009 issue, "Generation Next," by Bon Avila in the March 2009 issue, and "Riding Time as Fun Time: Prioritize It," in the April 2009 issue.
- Published
- 2009
138. What's in a face? : exploring components of social perception and social cognition in Williams syndrome and autism
- Author
-
Cole-Fletcher, Rachel
- Subjects
- 618.92
- Abstract
The social profiles seen in Williams syndrome (WS) and autism (ASD) have often been cited as mirror opposites of one another, with hyper-sociable behaviours seen in Williams syndrome and a disinterest in social engagement evidenced in autism. Studies investigating the social-perceptual abilities of individuals with these neurodevelopmental disorders have found overlapping profiles, with a tendency towards using more featural processing strategies when interpreting information from faces, and deficits in recognising and interpreting the various facial cues that provide social information. It is therefore likely that differences in social approach behaviours in the two groups are driven by a more social-cognitive mechanism. The focus of this thesis was on answering the overarching question: What meaning do faces and socially relevant stimuli have for children with Williams syndrome and autism? Six experiments examined the recognition, attribution, description and understanding of emotions and social cues from faces and socially relevant scenes, amongst WS and ASD individuals relative to their typically developing peers. It was found that the social-perceptual profiles of individuals with the neurodevelopmental disorders were markedly similar, with accuracy for identifying emotions being at nonverbal mental (but not chronological) age level. A tendency towards differences emerged in terms of the types of attribution and descriptions that individuals made, with those with ASD focusing more on physical aspects of social and non-social stimuli whilst individuals with WS showed more of an atypicality in the understanding of emotions and social contexts. The lack of any clear differentiation between individuals with ASD and WS in both the social-perceptual and social-cognitive domains is in line with recent research pointing to the extreme heterogeneity seen in these groups. The issue of overlaps and dissociations within such heterogeneous groups provides the theoretical framework for this thesis.
- Published
- 2014
139. Tamoxifen for the treatment of myeloproliferative neoplasms: A Phase II clinical trial and exploratory analysis.
- Author
-
Fang Z, Corbizi Fattori G, McKerrell T, Boucher RH, Jackson A, Fletcher RS, Forte D, Martin JE, Fox S, Roberts J, Glover R, Harris E, Bridges HR, Grassi L, Rodriguez-Meira A, Mead AJ, Knapper S, Ewing J, Butt NM, Jain M, Francis S, Clark FJ, Coppell J, McMullin MF, Wadelin F, Narayanan S, Milojkovic D, Drummond MW, Sekhar M, ElDaly H, Hirst J, Paramor M, Baxter EJ, Godfrey AL, Harrison CN, and Méndez-Ferrer S
- Subjects
- Humans, Janus Kinase 2 genetics, Janus Kinase 2 metabolism, Hematopoietic Stem Cells metabolism, Signal Transduction, Tamoxifen therapeutic use, Tamoxifen metabolism, Mutation, Calreticulin genetics, Calreticulin metabolism, Myeloproliferative Disorders drug therapy, Myeloproliferative Disorders genetics, Myeloproliferative Disorders pathology, Neoplasms metabolism
- Abstract
Current therapies for myeloproliferative neoplasms (MPNs) improve symptoms but have limited effect on tumor size. In preclinical studies, tamoxifen restored normal apoptosis in mutated hematopoietic stem/progenitor cells (HSPCs). TAMARIN Phase-II, multicenter, single-arm clinical trial assessed tamoxifen's safety and activity in patients with stable MPNs, no prior thrombotic events and mutated JAK2
V617F , CALRins5 or CALRdel52 peripheral blood allele burden ≥20% (EudraCT 2015-005497-38). 38 patients were recruited over 112w and 32 completed 24w-treatment. The study's A'herns success criteria were met as the primary outcome ( ≥ 50% reduction in mutant allele burden at 24w) was observed in 3/38 patients. Secondary outcomes included ≥25% reduction at 24w (5/38), ≥50% reduction at 12w (0/38), thrombotic events (2/38), toxicities, hematological response, proportion of patients in each IWG-MRT response category and ELN response criteria. As exploratory outcomes, baseline analysis of HSPC transcriptome segregates responders and non-responders, suggesting a predictive signature. In responder HSPCs, longitudinal analysis shows high baseline expression of JAK-STAT signaling and oxidative phosphorylation genes, which are downregulated by tamoxifen. We further demonstrate in preclinical studies that in JAK2V617F+ cells, 4-hydroxytamoxifen inhibits mitochondrial complex-I, activates integrated stress response and decreases pathogenic JAK2-signaling. These results warrant further investigation of tamoxifen in MPN, with careful consideration of thrombotic risk., (© 2023. The Author(s).)- Published
- 2023
- Full Text
- View/download PDF
140. Ponatinib with fludarabine, cytarabine, idarubicin, and granulocyte colony-stimulating factor chemotherapy for patients with blast-phase chronic myeloid leukaemia (MATCHPOINT): a single-arm, multicentre, phase 1/2 trial.
- Author
-
Copland M, Slade D, McIlroy G, Horne G, Byrne JL, Rothwell K, Brock K, De Lavallade H, Craddock C, Clark RE, Smith ML, Fletcher R, Bishop R, Milojkovic D, and Yap C
- Subjects
- Adolescent, Adult, Cytarabine adverse effects, Female, Granulocyte Colony-Stimulating Factor adverse effects, Humans, Idarubicin adverse effects, Imidazoles adverse effects, Male, Pyridazines adverse effects, Vidarabine adverse effects, Vidarabine analogs & derivatives, Antineoplastic Combined Chemotherapy Protocols adverse effects, Leukemia, Myelogenous, Chronic, BCR-ABL Positive drug therapy
- Abstract
Background: Outcomes for patients with blast-phase chronic myeloid leukaemia are poor. Long-term survival depends on reaching a second chronic phase, followed by allogeneic haematopoietic stem-cell transplantation (HSCT). We investigated whether the novel combination of the tyrosine-kinase inhibitor ponatinib with fludarabine, cytarabine, granulocyte colony-stimulating factor, and idarubicin (FLAG-IDA) could improve response and optimise allogeneic HSCT outcomes in patients with blast-phase chronic myeloid leukaemia. The aim was to identify a dose of ponatinib, which combined with FLAG-IDA, showed clinically meaningful activity and tolerability., Methods: MATCHPOINT was a seamless, phase 1/2, multicentre trial done in eight UK Trials Acceleration Programme-funded centres. Eligible participants were adults (aged ≥16 years) with Philadelphia chromosome-positive or BCR-ABL1-positive blast-phase chronic myeloid leukaemia, suitable for intensive chemotherapy. Participants received up to two cycles of ponatinib with FLAG-IDA. Experimental doses of oral ponatinib (given from day 1 to day 28 of FLAG-IDA) were between 15 mg alternate days and 45 mg once daily and the starting dose was 30 mg once daily. Intravenous fludarabine (30 mg/m
2 for 5 days), cytarabine (2 g/m2 for 5 days), and idarubicin (8 mg/m2 for 3 days), and subcutaneous granulocyte colony-stimulating factor (if used), were delivered according to local protocols. We used an innovative EffTox design to investigate the activity and tolerability of ponatinib-FLAG-IDA; the primary endpoints were the optimal ponatinib dose meeting prespecified thresholds of activity (inducement of second chronic phase defined as either haematological or minor cytogenetic response) and tolerability (dose-limiting toxicties). Analyses were planned on an intention-to-treat basis. MATCHPOINT was registered as an International Standard Randomised Controlled Trial, ISRCTN98986889, and has completed recruitment; the final results are presented., Findings: Between March 19, 2015, and April 26, 2018, 17 patients (12 men, five women) were recruited, 16 of whom were evaluable for the coprimary outcomes. Median follow-up was 41 months (IQR 36-48). The EffTox model simultaneously considered clinical responses and dose-limiting toxicities, and determined the optimal ponatinib dose as 30 mg daily, combined with FLAG-IDA. 11 (69%) of 16 patients were in the second chronic phase after one cycle of treatment. Four (25%) patients had a dose-limiting toxicity (comprising cardiomyopathy and grade 4 increased alanine aminotransferase, cerebral venous sinus thrombosis, grade 3 increased amylase, and grade 4 increased alanine aminotransferase), fulfilling the criteria for clinically relevant activity and toxicity. 12 (71%) of 17 patients proceeded to allogeneic HSCT. The most common grade 3-4 non-haematological adverse events were lung infection (n=4 [24%]), fever (n=3 [18%]), and hypocalcaemia (n=3 [18%]). There were 12 serious adverse events in 11 (65%) patients. Three (18%) patients died due to treatment-related events (due to cardiomyopathy, pulmonary haemorrhage, and bone marrow aplasia)., Interpretation: Ponatinib-FLAG-IDA can induce second chronic phase in patients with blast-phase chronic myeloid leukaemia, representing an active salvage therapy to bridge to allogeneic HSCT. The number of treatment-related deaths is not in excess of what would be expected in this very high-risk group of patients receiving intensive chemotherapy. The efficient EffTox method is a model for investigating novel therapies in ultra-orphan cancers., Funding: Blood Cancer UK and Incyte., Competing Interests: Declaration of interests MC has received research funding from Novartis, Bristol Myers Squibb, Cyclacel, and Takeda/Incyte; is an advisory board member for Bristol Myers Squibb, Novartis, Incyte, Daiichi Sankyo, and Pfizer; has received honoraria from Astellas, Bristol Myers Squibb, Novartis, Incyte, Pfizer, and Gilead. JLB is on the advisory board for and has received honoraria from Incyte. KR is on the advisory board for Novartis; and has received honoraria from Novartis, Incyte, Pfizer, and Daiichi Sankyo. KB is employed by UCB; has received personal fees from Eli Lilly and Invex Therapeutics; has received reimbursement from Merck and Roche; and holds shares in AstraZeneca and GlaxoSmithKline. HDL has received research funding from Incyte and Bristol Myers Squibb; and has received speaker fees from Incyte, Bristol Myers Squibb, and Pfizer. REC has received research support and honoraria from Novartis and Bristol Myers Squibb; and has received honoraria from Pfizer in the past 3 years. MLS is on the advisory board for Daiichi Sankyo and Pfizer; and has received honoraria from ARIAD. DM has received honoraria and been part of the speakers bureau for Novartis, Incyte, Bristol Myers Squibb, and Pfizer. CY has received personal fees from Celgene and Faron Pharmaceuticals, outside the submitted work. All other authors declare no competing interests., (Copyright © 2022 Elsevier Ltd. All rights reserved.)- Published
- 2022
- Full Text
- View/download PDF
141. Metabolic tracing reveals novel adaptations to skeletal muscle cell energy production pathways in response to NAD + depletion.
- Author
-
Oakey LA, Fletcher RS, Elhassan YS, Cartwright DM, Doig CL, Garten A, Thakker A, Maddocks ODK, Zhang T, Tennant DA, Ludwig C, and Lavery GG
- Abstract
Background: Skeletal muscle is central to whole body metabolic homeostasis, with age and disease impairing its ability to function appropriately to maintain health. Inadequate NAD
+ availability is proposed to contribute to pathophysiology by impairing metabolic energy pathway use. Despite the importance of NAD+ as a vital redox cofactor in energy production pathways being well-established, the wider impact of disrupted NAD+ homeostasis on these pathways is unknown. Methods: We utilised skeletal muscle myotube models to induce NAD+ depletion, repletion and excess and conducted metabolic tracing to provide comprehensive and detailed analysis of the consequences of altered NAD+ metabolism on central carbon metabolic pathways. We used stable isotope tracers, [1,2-13C] D-glucose and [U-13 C] glutamine, and conducted combined 2D-1H,13C-heteronuclear single quantum coherence (HSQC) NMR spectroscopy and GC-MS analysis. Results: NAD+ excess driven by nicotinamide riboside (NR) supplementation within skeletal muscle cells resulted in enhanced nicotinamide clearance, but had no effect on energy homeostasis or central carbon metabolism. Nicotinamide phosphoribosyltransferase (NAMPT) inhibition induced NAD+ depletion and resulted in equilibration of metabolites upstream of glyceraldehyde phosphate dehydrogenase (GAPDH). Aspartate production through glycolysis and TCA cycle activity was increased in response to low NAD+ , which was rapidly reversed with repletion of the NAD+ pool using NR. NAD+ depletion reversibly inhibits cytosolic GAPDH activity, but retains mitochondrial oxidative metabolism, suggesting differential effects of this treatment on sub-cellular pyridine pools. When supplemented, NR efficiently reversed these metabolic consequences. However, the functional relevance of increased aspartate levels after NAD+ depletion remains unclear, and requires further investigation. Conclusions: These data highlight the need to consider carbon metabolism and clearance pathways when investigating NAD+ precursor usage in models of skeletal muscle physiology., Competing Interests: No competing interests were disclosed.- Published
- 2019
- Full Text
- View/download PDF
142. Nicotinamide Riboside Augments the Aged Human Skeletal Muscle NAD + Metabolome and Induces Transcriptomic and Anti-inflammatory Signatures.
- Author
-
Elhassan YS, Kluckova K, Fletcher RS, Schmidt MS, Garten A, Doig CL, Cartwright DM, Oakey L, Burley CV, Jenkinson N, Wilson M, Lucas SJE, Akerman I, Seabright A, Lai YC, Tennant DA, Nightingale P, Wallis GA, Manolopoulos KN, Brenner C, Philp A, and Lavery GG
- Subjects
- Aged, Aged, 80 and over, Aging drug effects, Cross-Sectional Studies, Cytokines drug effects, Double-Blind Method, Humans, Male, Muscle, Skeletal drug effects, NAD metabolism, Niacinamide pharmacology, Pyridinium Compounds, Aging metabolism, Anti-Inflammatory Agents blood, Cytokines blood, Metabolome drug effects, Muscle, Skeletal metabolism, Niacinamide analogs & derivatives, Transcriptome drug effects
- Abstract
Nicotinamide adenine dinucleotide (NAD
+ ) is modulated by conditions of metabolic stress and has been reported to decline with aging in preclinical models, but human data are sparse. Nicotinamide riboside (NR) supplementation ameliorates metabolic dysfunction in rodents. We aimed to establish whether oral NR supplementation in aged participants can increase the skeletal muscle NAD+ metabolome and if it can alter muscle mitochondrial bioenergetics. We supplemented 12 aged men with 1 g NR per day for 21 days in a placebo-controlled, randomized, double-blind, crossover trial. Targeted metabolomics showed that NR elevated the muscle NAD+ metabolome, evident by increased nicotinic acid adenine dinucleotide and nicotinamide clearance products. Muscle RNA sequencing revealed NR-mediated downregulation of energy metabolism and mitochondria pathways, without altering mitochondrial bioenergetics. NR also depressed levels of circulating inflammatory cytokines. Our data establish that oral NR is available to aged human muscle and identify anti-inflammatory effects of NR., (Copyright © 2019 The Author(s). Published by Elsevier Inc. All rights reserved.)- Published
- 2019
- Full Text
- View/download PDF
143. Metabolic tracing reveals novel adaptations to skeletal muscle cell energy production pathways in response to NAD + depletion.
- Author
-
Oakey LA, Fletcher RS, Elhassan YS, Cartwright DM, Doig CL, Garten A, Thakker A, Maddocks ODK, Zhang T, Tennant DA, Ludwig C, and Lavery GG
- Abstract
Background: Skeletal muscle is central to whole body metabolic homeostasis, with age and disease impairing its ability to function appropriately to maintain health. Inadequate NAD
+ availability is proposed to contribute to pathophysiology by impairing metabolic energy pathway use. Despite the importance of NAD+ as a vital redox cofactor in energy production pathways being well-established, the wider impact of disrupted NAD+ homeostasis on these pathways is unknown. Methods: We utilised skeletal muscle myotube models to induce NAD+ depletion, repletion and excess and conducted metabolic tracing to provide comprehensive and detailed analysis of the consequences of altered NAD+ metabolism on central carbon metabolic pathways. We used stable isotope tracers, [1,2-13C] D-glucose and [U-13 C] glutamine, and conducted combined 2D-1H,13C-heteronuclear single quantum coherence (HSQC) NMR spectroscopy and GC-MS analysis. Results: NAD+ excess driven by nicotinamide riboside (NR) supplementation within skeletal muscle cells results in enhanced nicotinamide clearance, but had no effect on energy homeostasis or central carbon metabolism. Nicotinamide phosphoribosyltransferase (NAMPT) inhibition induced NAD+ depletion and resulted in equilibration of metabolites upstream of glyceraldehyde phosphate dehydrogenase (GAPDH). Aspartate production through glycolysis and TCA cycle activity is increased in response to low NAD+ , which is rapidly reversed with repletion of the NAD+ pool using NR. NAD+ depletion reversibly inhibits cytosolic GAPDH activity, but retains mitochondrial oxidative metabolism, suggesting differential effects of this treatment on sub-cellular pyridine pools. When supplemented, NR efficiently reverses these metabolic consequences. However, the functional relevance of increased aspartate levels after NAD+ depletion remains unclear, and requires further investigation. Conclusions: These data highlight the need to consider carbon metabolism and clearance pathways when investigating NAD+ precursor usage in models of skeletal muscle physiology., Competing Interests: No competing interests were disclosed.- Published
- 2018
- Full Text
- View/download PDF
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