15 research outputs found
The effect of adenosine monophosphate deaminase overexpression on the accumulation of umami-related metabolites in tomatoes
Taste is perceived as one of a combination of five sensations, sweet, sour, bitter, salty, and umami. The umami taste is best known as a savoury sensation and plays a central role in food flavour, palatability, and eating satisfaction. Umami flavour can be imparted by the presence of glutamate and is greatly enhanced by the addition of ribonucleotides, such as inosine monophosphate (IMP) and guanosine monophosphate (GMP). The production of IMP is regulated by the enzyme adenosine monophosphate (AMP) deaminase which functions to convert AMP into IMP. We have generated transgenic tomato (Solanum lycopersicum) lines over expressing AMP deaminase under the control of a fruit-specific promoter. The transgenic lines showed substantially enhanced levels of AMP deaminase expression in comparison to the wild-type control. Elevated AMP deaminase levels resulted in the reduced accumulation of glutamate and increased levels of the umami nucleotide GMP. AMP concentrations were unchanged. The effects on the levels of glutamate and GMP were unexpected and are discussed in relation to the metabolite flux within this pathway
The impact of viral mutations on recognition by SARS-CoV-2 specific TÂ cells.
We identify amino acid variants within dominant SARS-CoV-2 TÂ cell epitopes by interrogating global sequence data. Several variants within nucleocapsid and ORF3a epitopes have arisen independently in multiple lineages and result in loss of recognition by epitope-specific TÂ cells assessed by IFN-Îł and cytotoxic killing assays. Complete loss of TÂ cell responsiveness was seen due to Q213K in the Aâ01:01-restricted CD8+ ORF3a epitope FTSDYYQLY207-215; due to P13L, P13S, and P13T in the Bâ27:05-restricted CD8+ nucleocapsid epitope QRNAPRITF9-17; and due to T362I and P365S in the Aâ03:01/Aâ11:01-restricted CD8+ nucleocapsid epitope KTFPPTEPK361-369. CD8+ TÂ cell lines unable to recognize variant epitopes have diverse TÂ cell receptor repertoires. These data demonstrate the potential for TÂ cell evasion and highlight the need for ongoing surveillance for variants capable of escaping TÂ cell as well as humoral immunity.This work is supported by the UK Medical Research Council (MRC); Chinese Academy of Medical Sciences(CAMS) Innovation Fund for Medical Sciences (CIFMS), China; National Institute for Health Research (NIHR)Oxford Biomedical Research Centre, and UK Researchand Innovation (UKRI)/NIHR through the UK Coro-navirus Immunology Consortium (UK-CIC). Sequencing of SARS-CoV-2 samples and collation of data wasundertaken by the COG-UK CONSORTIUM. COG-UK is supported by funding from the Medical ResearchCouncil (MRC) part of UK Research & Innovation (UKRI),the National Institute of Health Research (NIHR),and Genome Research Limited, operating as the Wellcome Sanger Institute. T.I.d.S. is supported by a Well-come Trust Intermediate Clinical Fellowship (110058/Z/15/Z). L.T. is supported by the Wellcome Trust(grant number 205228/Z/16/Z) and by theUniversity of Liverpool Centre for Excellence in Infectious DiseaseResearch (CEIDR). S.D. is funded by an NIHR GlobalResearch Professorship (NIHR300791). L.T. and S.C.M.are also supported by the U.S. Food and Drug Administration Medical Countermeasures Initiative contract75F40120C00085 and the National Institute for Health Research Health Protection Research Unit (HPRU) inEmerging and Zoonotic Infections (NIHR200907) at University of Liverpool inpartnership with Public HealthEngland (PHE), in collaboration with Liverpool School of Tropical Medicine and the University of Oxford.L.T. is based at the University of Liverpool. M.D.P. is funded by the NIHR Sheffield Biomedical ResearchCentre (BRC â IS-BRC-1215-20017). ISARIC4C is supported by the MRC (grant no MC_PC_19059). J.C.K.is a Wellcome Investigator (WT204969/Z/16/Z) and supported by NIHR Oxford Biomedical Research Centreand CIFMS. The views expressed are those of the authors and not necessarily those of the NIHR or MRC
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Internal equity financing and the performance of multinational subsidiaries in emerging economies
We examine the internal equity financing of the multinational subsidiary which retains and reinvests its own earnings. Internal equity financing is a type of firm-specific advantage (FSA) along with other traditional FSAs in innovation, research and development, brands and management skills. It also reflects subsidiary-level financial management decision-making. Here we test the contributions of internal equity financing and subsidiary-level financial management decision-making to subsidiary performance, using original survey data from British multinational subsidiaries in six emerging countries in the South East Asia region. Our first finding is that internal equity financing acts as an FSA to improve subsidiary performance. Our second finding is that over 90% of financing sources (including capital investment by the parent firms) in the British subsidiaries come from internal funding. Our third finding is that subsidiary-level financial management decision-making has a statistically significant positive impact on subsidiary performance. Our findings advance the theoretical, empirical and managerial analysis of subsidiary performance in emerging economies
Changes in in-hospital mortality in the first wave of COVID-19: a multicentre prospective observational cohort study using the WHO Clinical Characterisation Protocol UK.
BackgroundMortality rates in hospitalised patients with COVID-19 in the UK appeared to decline during the first wave of the pandemic. We aimed to quantify potential drivers of this change and identify groups of patients who remain at high risk of dying in hospital.MethodsIn this multicentre prospective observational cohort study, the International Severe Acute Respiratory and Emerging Infections Consortium WHO Clinical Characterisation Protocol UK recruited a prospective cohort of patients with COVID-19 admitted to 247 acute hospitals in England, Scotland, and Wales during the first wave of the pandemic (between March 9 and Aug 2, 2020). We included all patients aged 18 years and older with clinical signs and symptoms of COVID-19 or confirmed COVID-19 (by RT-PCR test) from assumed community-acquired infection. We did a three-way decomposition mediation analysis using natural effects models to explore associations between week of admission and in-hospital mortality, adjusting for confounders (demographics, comorbidities, and severity of illness) and quantifying potential mediators (level of respiratory support and steroid treatment). The primary outcome was weekly in-hospital mortality at 28 days, defined as the proportion of patients who had died within 28 days of admission of all patients admitted in the observed week, and it was assessed in all patients with an outcome. This study is registered with the ISRCTN Registry, ISRCTN66726260.FindingsBetween March 9, and Aug 2, 2020, we recruited 80â713 patients, of whom 63â972 were eligible and included in the study. Unadjusted weekly in-hospital mortality declined from 32·3% (95% CI 31·8-32·7) in March 9 to April 26, 2020, to 16·4% (15·0-17·8) in June 15 to Aug 2, 2020. Reductions in mortality were observed in all age groups, in all ethnic groups, for both sexes, and in patients with and without comorbidities. After adjustment, there was a 32% reduction in the risk of mortality per 7-week period (odds ratio [OR] 0·68 [95% CI 0·65-0·71]). The higher proportions of patients with severe disease and comorbidities earlier in the first wave (March and April) than in June and July accounted for 10·2% of this reduction. The use of respiratory support changed during the first wave, with gradually increased use of non-invasive ventilation over the first wave. Changes in respiratory support and use of steroids accounted for 22·2%, OR 0·95 (0·94-0·95) of the reduction in in-hospital mortality.InterpretationThe reduction in in-hospital mortality in patients with COVID-19 during the first wave in the UK was partly accounted for by changes in the case-mix and illness severity. A significant reduction in in-hospital mortality was associated with differences in respiratory support and critical care use, which could partly reflect accrual of clinical knowledge. The remaining improvement in in-hospital mortality is not explained by these factors, and could be associated with changes in community behaviour, inoculum dose, and hospital capacity strain.FundingNational Institute for Health Research and the Medical Research Council