UCL University College London Eprints
UCL Eprints collects the work of UCL researchers and makes it freely available over the web, helping the worldwide scholarly community to discover UCL research. Institutional repositories like UCL Eprints complement the traditional academic publishing and scholarly communications processes. They raise the visibility of research and help to maximise its impact. UCL researchers are encouraged to deposit a copy of each journal article, conference paper, working paper, and any other research output, in the UCL Eprints at the earliest opportunity, ensuring that their research reaches as wide an audience as possible.
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Cellular glutathione content in the organ of Corti and its role during ototoxicity. - Majumder, P; Duchen, MR; Gale, JE
Glutathione (GSH) is the major scavenger of reactive oxygen species (ROS) inside cells. We used live confocal imaging in order to clarify the role of GSH in the biology of the organ of Corti, the sensory epithelium of the cochlea, before, during and after the onset of hearing and in ~1 year old mice. GSH content was measured using monochlorobimane (MCB), a non-fluorescent cell permeant bimane that reacts with GSH, forming a fluorescent adduct through a reaction catalyzed by glutathione-S-transferase. GSH content increased significantly in inner hair cells during maturation in young adult animals, whereas there was no significant change...
An evaluation of prospective motion correction (PMC) for high resolution quantitative MRI. - Callaghan, MF; Josephs, O; Herbst, M; Zaitsev, M; Todd, N; Weiskopf, N
Quantitative imaging aims to provide in vivo neuroimaging biomarkers with high research and diagnostic value that are sensitive to underlying tissue microstructure. In order to use these data to examine intra-cortical differences or to define boundaries between different myelo-architectural areas, high resolution data are required. The quality of such measurements is degraded in the presence of motion hindering insight into brain microstructure. Correction schemes are therefore vital for high resolution, whole brain coverage approaches that have long acquisition times and greater sensitivity to motion. Here we evaluate the use of prospective motion correction (PMC) via an optical tracking system to...
Diatom response to mid-Holocene climate in three small Arctic lakes in northernmost Finnmark - Roberts, S; Jones, VJ; Allen, JR; Huntley, B
Palaeoclimatic reconstructions from lake sediment biological records can be challenging, due to variation in non-climatic factors, which alter ecosystem responses. To consider this, it is important to replicate a study regionally, so as to gain information on spatial variability of ecosystem response and the influence of site-specific conditions. Previous pollen-based palaeoclimatic records from three well-dated Arctic lake sites highlight the response of regional Scots Pine (Pinus sylvestris) and Mountain Birch (Betula pubescens ssp. czerepanovii) forest-tundra transition to Holocene climatic variability and suggest the northernmost Peninsulas of Finnmark to be climatically sensitive. This study analysed dated sediment sequences between c. 3970...
The Effects of Parental Behavior on Infants' Neural Processing of Emotion Expressions - Taylor-Colls, S; Fearon, RMP
Infants become sensitive to emotion expressions early in the 1st year and such sensitivity is likely crucial for social development and adaptation. Social interactions with primary caregivers may play a key role in the development of this complex ability. This study aimed to investigate how variations in parenting behavior affect infants' neural responses to emotional faces. Event-related potentials (ERPs) to emotional faces were recorded from 40 healthy 7-month-old infants (24 males). Parental behavior was assessed and coded using the Emotional Availability Scales during free-play interaction. Sensitive parenting was associated with increased amplitudes to positive facial expressions on the face-sensitive ERP...
The Nobody: Exploring Archaeological Identity with George Horsfield (1882-1956) - Thornton, AA
This article examines George Horsfield’s life and professional career in the Department of Antiquities in British Mandate Transjordan through his correspondence and images in the archives of UCL Institute of Archaeology. Through these documents, Horsfield’s multiple archaeological identities – architect, official and foreigner – are revealed. His experience, situated within the context of life in British Mandate Transjordan, is used to analyse the archaeologist within a wider history of antiquities departments in British imperial possessions.
Four Station Knee Simulator Wear Testing Comparing Titanium Niobium Nitride with Cobalt Chrome - Blunn GW, MRM
A new non-destructive method was applied in order to assess bone integrity. The method is based on measurement of bHypersensitivity to an orthopaedic implant was first published in 1966 and since then, in sensitive patients, is known to cause serious problems in joint replacement surgery. Titanium niobium nitride (TiNbN) can act as a surface coat for knee arthroplasty to “hide” the cobalt chrome (CoCr) femoral component beneath, therefore affording an immunoprivileged state. The aim of this study is to determine the wear properties of titanium niobium nitride against Ultra High Molecular Weight Polyethylene (UHMWPE) compared to cobalt chrome and to...
Super-Resolution Microscopy: A Virus’ Eye View of the Cell - Grove, J
It is difficult to observe the molecular choreography between viruses and host cell components, as they exist on a spatial scale beyond the reach of conventional microscopy. However, novel super-resolution microscopy techniques have cast aside technical limitations to reveal a nanoscale view of virus replication and cell biology. This article provides an introduction to super-resolution imaging; in particular, localisation microscopy, and explores the application of such technologies to the study of viruses and tetraspanins, the topic of this special issue.
Hedonism Before Bentham - Moen, Ole Martin
The hedonistic theories of Jeremy Bentham and John Stuart Mill are both widely known. Hedonism before Bentham, however, is much less known and, hitherto, no systematic presentation of hedonism’s early history has been written. In this paper I seek to fill this gap in the literature by providing an overview of hedonism in early Indian and ancient Greek thought (Sections 1-4), in Roman and Medieval thought (Section 5), and from the Renaissance until the Enlightenment (Section 6).
Adolescents Adapt More Slowly than Adults to Varying Reward Contingencies - Javadi, AH; Schmidt, DHK; Smolka, MN
It has been suggested that adolescents process rewards differently from adults, both cognitively and affectively. In an fMRI study we recorded brain BOLD activity of adolescents (age range = 14–15 years) and adults (age range = 20–39 years) to investigate the developmental changes in reward processing and decision-making. In a probabilistic reversal learning task, adolescents and adults adapted to changes in reward contingencies. We used a reinforcement learning model with an adaptive learning rate for each trial to model the adolescents' and adults' behavior. Results showed that adolescents possessed a shallower slope in the sigmoid curve governing the relation between...
Experimental determination of the membrane topology of the Plasmodium protease plasmepsin v. - Tarr, SJ; Osborne, AR
The malaria parasite exports hundreds of proteins into its host cell. The majority of exported proteins contain a Host-Targeting motif (also known as a Plasmodium export element) that directs them for export. Prior to export, the Host-Targeting motif is cleaved by the endoplasmic reticulum-resident protease Plasmepsin V and the newly generated N-terminus is N-α-acetylated by an unidentified enzyme. The cleaved, N-α-acetylated protein is trafficked to the parasitophorous vacuole, where it is translocated across the vacuole membrane. It is clear that cleavage and N-α-acetylation of the Host-Targeting motif occur at the endoplasmic reticulum, and it has been proposed that Host-Targeting motif...
Time, monetary and other costs of participation in family-based child weight management interventions: qualitative and systematic review evidence. - Arai, L; Panca, M; Morris, S; Curtis-Tyler, K; Lucas, PJ; Roberts, HM
Childhood overweight and obesity have health and economic impacts on individuals and the wider society. Families participating in weight management programmes may foresee or experience monetary and other costs which deter them from signing up to or completing programmes. This is recognised in the health economics literature, though within this sparse body of work, costs to families are often narrowly defined and not fully accounted for. A societal perspective incorporating a broader array of costs may provide a more accurate picture. This paper brings together a review of the health economics literature on the costs to families attending child weight...
Predictors of Human Papillomavirus Awareness and Knowledge in 2013. The Importance of Health Literacy - Smith, SG; Forster, AS; Kobayashi, LC
The recent article by Blake et al.1 highlights the important gaps in awareness and knowledge about human papillomavirus (HPV), its relationship with cancer, and the HPV vaccine in the U.S. population. As noted by the authors, the introduction of a health technology can lead to health inequalities if there is differential learning among population subgroups, the so-called “Knowledge Gap Hypothesis.” Comparisons with previous analyses of the Health Information and National Trends Survey (HINTS) suggest awareness has increased among the U.S.
Molecular chaperones and neuronal proteostasis. - Smith, HL; Li, W; Cheetham, ME
Protein homeostasis (proteostasis) is essential for maintaining the functionality of the proteome. The disruption of proteostasis, due to genetic mutations or an age-related decline, leads to aberrantly folded proteins that typically lose their function. The accumulation of misfolded and aggregated protein is also cytotoxic and has been implicated in the pathogenesis of neurodegenerative diseases. Neurons have developed an intrinsic protein quality control network, of which molecular chaperones are an essential component. Molecular chaperones function to promote efficient folding and target misfolded proteins for refolding or degradation. Increasing molecular chaperone expression can suppress protein aggregation and toxicity in numerous models of...
Glycine decarboxylase deficiency causes neural tube defects and features of non-ketotic hyperglycinemia in mice. - Pai, YJ; Leung, KY; Savery, D; Hutchin, T; Prunty, H; Heales, S; Brosnan, ME; Brosnan, JT; Copp, AJ; Greene, ND
Glycine decarboxylase (GLDC) acts in the glycine cleavage system to decarboxylate glycine and transfer a one-carbon unit into folate one-carbon metabolism. GLDC mutations cause a rare recessive disease non-ketotic hyperglycinemia (NKH). Mutations have also been identified in patients with neural tube defects (NTDs); however, the relationship between NKH and NTDs is unclear. We show that reduced expression of Gldc in mice suppresses glycine cleavage system activity and causes two distinct disease phenotypes. Mutant embryos develop partially penetrant NTDs while surviving mice exhibit post-natal features of NKH including glycine accumulation, early lethality and hydrocephalus. In addition to elevated glycine, Gldc disruption...
Gastrointestinal release behaviour of modified-release drug products: Dynamic dissolution testing of mesalazine formulations. - Goyanes, A; Hatton, GB; Merchant, HA; Basit, AW
The aminosalicylate mesalazine (mesalamine) forms the mainstay of treatment in ulcerative colitis (UC), a disease for which many commercial modified-release products have been developed with the aim of providing targeted gastrointestinal release. The release profiles of five of these commercial formulations were evaluated in bicarbonate buffer using a novel dissolution model that mimics the dynamic conditions of the gastrointestinal tract. Monolithic and multi-particulate mesalazine formulations with pH-dependent and/or independent release mechanisms were evaluated (Asacol(®) 800, Octasa(®), Mezavant(®) XL, Salofalk(®), Pentasa(®)), and each of the products displayed a distinctive dissolution profile. The dissolution results for Mezavant(®) XL (Lialda(®)) (lag time 290min)...
Construction of stable packaging cell lines for clinical lentiviral vector production. - Sanber, KS; Knight, SB; Stephen, SL; Bailey, R; Escors, D; Minshull, J; Santilli, G; Thrasher, AJ; Collins, MK; Takeuchi, Y
Lentiviral vectors are useful experimental tools for stable gene delivery and have been used to treat human inherited genetic disorders and hematologic malignancies with promising results. Because some of the lentiviral vector components are cytotoxic, transient plasmid transfection has been used to produce the large batches needed for clinical trials. However, this method is costly, poorly reproducible and hard to scale up. Here we describe a general method for construction of stable packaging cell lines that continuously produce lentiviral vectors. This uses Cre recombinase-mediated cassette exchange to insert a codon-optimised HIV-1 Gag-Pol expression construct in a continuously expressed locus in...
Bobbles and values: An ethnography of de-bobbling garments in postsocialist urban Romania - Cr ciun, M
Based on research on clothing consumption in a provincial Romanian town, this article focuses on bobbling (pilling) and on reflections on its appearances and progression. Bobbling is considered an index of a faulty or decaying materiality, and an index of usage and, possibly, carelessness and hardship. It limits an individual’s ability to project a desired self. It hints at an individual’s inability to present a renewed self. It not only disrupts a common process of value creation through the act of dressing, but also exposes a disputed process of value creation through the consumption of certain objects. It foregrounds a...
Lepidocrocite-like TiO2 and TiO2(110)– (1 × 2) supported on W(100) - Harrison, GT
Ultrathin films of TiO2 were grown on a W(100)-O(2 × 1) substrate and characterised with a combination of scanning tunneling microscopy (STM) and low energy electron diffraction (LEED). In addition to islands of rutile TiO2(110) with (1 × 1) termination that were reported previously, we also observed rutile TiO2(110) islands with a (1 × 2) film termination. A lepidocrocite-like TiO2 nanosheet was also observed on the W(100) surface. High-resolution STM images show that the nanosheet grows in the principal orthogonal directions of the W(100) substrate and forms a commensurate (1 × 7) coincident cell.