190 research outputs found

    Stakeholder perceptions of marine plastic waste management in the United Kingdom

    Get PDF
    Plastic pollution is a significant threat to the marine environment. Although scientific interest in the environmental impacts of plastic pollution has grown rapidly over the last decade, there has been a relative lag in public, industry and government interest. The recent BBC Blue Planet II documentary has, however, provoked a national increase in awareness to the problems of plastic pollution in the United Kingdom (UK), and has inspired the government to introduce taxation policy changes aiming to reduce consumption. It is therefore necessary to better understand the diverse range of opinions that surround the ocean plastic waste problem, economic policy solutions and consumption responsibilities. We employ a Q-methodological study to address key stakeholder viewpoints from ENGO, government agency, retailer, marine science and citizen representatives in the UK. We find four distinct emergent discourses surrounding this topic, labelled: a) Socio-cultural visibility and responsibility, b) Dragons of inaction – disempowerment and defeatism, c) Value-action gap, d) Refuting retailer responsibility. We also identify a clear consensus that current and proposed government policy is not radical enough – the focus needs to move beyond single-product taxes and levies on disposal items (e.g bags, coffee cups), to a deeper reflection about public awareness raising and education, defining waste responsibilities more clearly, and working to change the habits and unsustainable practices of consumers in the face of public apathy and a resistant retail environment

    DNA Microarray Genotyping and Virulence and Antimicrobial Resistance Gene Profiling of Methicillin-Resistant Staphylococcus aureus Bloodstream Isolates from Renal Patients.

    Get PDF
    Thirty-six methicillin-resistant Staphylococcus aureus (MRSA) bloodstream isolates from renal patients were genetically characterized by DNA microarray analysis and spa typing. The isolates were highly clonal, belonging mainly to ST22-MRSA-IV. The immune evasion and enterotoxin gene clusters were found in 29/36 (80%) and 33/36 (92%) of isolates, respectively

    Rapid detection of ERG11 gene mutations in clinical Candida albicans isolates with reduced susceptibility to fluconazole by rolling circle amplification and DNA sequencing

    Get PDF
    BACKGROUND Amino acid substitutions in the target enzyme Erg11p of azole antifungals contribute to clinically-relevant azole resistance in Candida albicans. A simple molecular method for rapid detection of ERG11 gene mutations would be an advantage as a screening tool to identify potentially-resistant strains and to track their movement. To complement DNA sequencing, we developed a padlock probe and rolling circle amplification (RCA)-based method to detect a series of mutations in the C. albicans ERG11 gene using "reference" azole-resistant isolates with known mutations. The method was then used to estimate the frequency of ERG11 mutations and their type in 25 Australian clinical C. albicans isolates with reduced susceptibility to fluconazole and in 23 fluconazole-susceptible isolates. RCA results were compared DNA sequencing. RESULTS The RCA assay correctly identified all ERG11 mutations in eight "reference" C. albicans isolates. When applied to 48 test strains, the RCA method showed 100% agreement with DNA sequencing where an ERG11 mutation-specific probe was used. Of 20 different missense mutations detected by sequencing in 24 of 25 (96%) isolates with reduced fluconazole susceptibility, 16 were detected by RCA. Five missense mutations were detected by both methods in 18 of 23 (78%) fluconazole-susceptible strains. DNA sequencing revealed that mutations in non-susceptible isolates were all due to homozygous nucleotide changes. With the exception of the mutations leading to amino acid substitution E266D, those in fluconazole-susceptible strains were heterozygous. Amino acid substitutions common to both sets of isolates were D116E, E266D, K128T, V437I and V488I. Substitutions unique to isolates with reduced fluconazole susceptibility were G464 S (n = 4 isolates), G448E (n = 3), G307S (n = 3), K143R (n = 3) and Y123H, S405F and R467K (each n = 1). DNA sequencing revealed a novel substitution, G450V, in one isolate. CONCLUSION The sensitive RCA assay described here is a simple, robust and rapid (2 h) method for the detection of ERG11 polymorphisms. It showed excellent concordance with ERG11 sequencing and is a potentially valuable tool to track the emergence and spread of azole-resistant C. albicans and to study the epidemiology of ERG11 mutations. The RCA method is applicable to the study of azole resistance in other fungi.Huiping Wang, Fanrong Kong, Tania C Sorrell, Bin Wang, Paul McNicholas, Namfon Pantarat, David Ellis, Meng Xiao, Fred Widmer and Sharon CA Che

    Hereditary leukoencephalopathy with axonal spheroids: a spectrum of phenotypes from CNS vasculitis to parkinsonism in an adult onset leukodystrophy series

    Get PDF
    Background: Hereditary diffuse leukoencephalopathy with neuroaxonal spheroids (HDLS) is a hereditary, adult onset leukodystrophy which is characterised by the presence of axonal loss, axonal spheroids and variably present pigmented macrophages on pathological examination. It most frequently presents in adulthood with dementia and personality change. HDLS has recently been found to be caused by mutations in the colony stimulating factor-1 receptor (CSF1R) gene. Methods: In this study, we sequenced the CSF1R gene in a cohort of 48 patients from the UK, Greece and Ireland with adult onset leukodystrophy of unknown cause. Results: Five pathogenic mutations were found, including three novel mutations. The presentations ranged from suspected central nervous system (CNS) vasculitis to extrapyramidal to cognitive phenotypes. The case histories and imaging are presented here, in addition to neuropathological findings from two cases with novel mutations. Conclusion: We estimate that CSF1R mutations account for 10% of idiopathic adult onset leukodystrophies and that genetic testing for CSF1R mutations is essential in adult patients presenting with undefined CNS vasculitis or a leukodystrophy with prominent neuropsychiatric signs or dementia

    Bacterial rotary export ATPases are allosterically regulated by the nucleotide second messenger cyclic-di-GMP

    Get PDF
    The widespread second messenger molecule cyclic di-GMP (cdG) regulates the transition from motile and virulent lifestyles to sessile, biofilm-forming ones in a wide range of bacteria. Many pathogenic and commensal bacterial-host interactions are known to be controlled by cdG signaling. Although the biochemistry of cyclic dinucleotide metabolism is well understood, much remains to be discovered about the downstream signaling pathways that induce bacterial responses upon cdG binding. As part of our ongoing research into the role of cdG signaling in plant-associated Pseudomonas species, we carried out an affinity capture screen for cdG binding proteins in the model organism Pseudomonas fluorescens SBW25. The flagella export AAA+ ATPase FliI was identified as a result of this screen and subsequently shown to bind specifically to the cdG molecule, with a KD in the low micromolar range. The interaction between FliI and cdG appears to be very widespread. In addition to FliI homologs from diverse bacterial species, high affinity binding was also observed for the type III secretion system homolog HrcN and the type VI ATPase ClpB2. The addition of cdG was shown to inhibit FliI and HrcN ATPase activity in vitro. Finally, a combination of site-specific mutagenesis, mass spectrometry, and in silico analysis was used to predict that cdG binds to FliI in a pocket of highly conserved residues at the interface between two FliI subunits. Our results suggest a novel, fundamental role for cdG in controlling the function of multiple important bacterial export pathways, through direct allosteric control of export ATPase proteins

    Caloric restriction induces changes in insulin and body weight measurements that are inversely associated with subsequent weight regain

    Get PDF
    BACKGROUND: Successful weight maintenance following weight loss is challenging for many people. Identifying predictors of longer-term success will help target clinical resources more effectively. To date, focus has been predominantly on the identification of predictors of weight loss. The goal of the current study was to determine if changes in anthropometric and clinical parameters during acute weight loss are associated with subsequent weight regain. METHODOLOGY: The study consisted of an 8-week low calorie diet (LCD) followed by a 6-month weight maintenance phase. Anthropometric and clinical parameters were analyzed before and after the LCD in the 285 participants (112 men, 173 women) who regained weight during the weight maintenance phase. Mixed model ANOVA, Spearman correlation, and linear regression were used to study the relationships between clinical measurements and weight regain. PRINCIPAL FINDINGS: Gender differences were observed for body weight and several clinical parameters at both baseline and during the LCD-induced weight loss phase. LCD-induced changes in BMI (Spearman's ρ = 0.22, p = 0.0002) were inversely associated with weight regain in both men and women. LCD-induced changes in fasting insulin (ρ = 0.18, p = 0.0043) and HOMA-IR (ρ = 0.19, p = 0.0023) were also associated independently with weight regain in both genders. The aforementioned associations remained statistically significant in regression models taking account of variables known to independently influence body weight. CONCLUSIONS/SIGNIFICANCE: LCD-induced changes in BMI, fasting insulin, and HOMA-IR are inversely associated with weight regain in the 6-month period following weight loss

    Supporting Remote Survey Data Analysis by Co-researchers with Learning Disabilities through Inclusive and Creative Practices and Data Science Approaches

    Full text link
    Through a process of robust co-design, we created a bespoke accessible survey platform to explore the role of co-researchers with learning disabilities (LDs) in research design and analysis. A team of co-researchers used this system to create an online survey to challenge public understanding of LDs [3]. Here, we describe and evaluate the process of remotely co-analyzing the survey data across 30 meetings in a research team consisting of academics and nonacademics with diverse abilities amid new COVID-19 lockdown challenges. Based on survey data with >1,500 responses, we first coanalyzed demographics using graphs and art & design approaches. Next, co-researchers co-analyzed the output of machine learningbased structural topic modelling (STM) applied to open-ended text responses. We derived an efficient five-steps STM co-analysis process for creative, inclusive, and critical engagement of data by coresearchers. Co-researchers observed that by trying to understand and impact public opinion, their own perspectives also changed

    Structural and functional insight into human O-GlcNAcase.

    Get PDF
    O-GlcNAc hydrolase (OGA) removes O-linked N-acetylglucosamine (O-GlcNAc) from a myriad of nucleocytoplasmic proteins. Through co-expression and assembly of OGA fragments, we determined the three-dimensional structure of human OGA, revealing an unusual helix-exchanged dimer that lays a structural foundation for an improved understanding of substrate recognition and regulation of OGA. Structures of OGA in complex with a series of inhibitors define a precise blueprint for the design of inhibitors that have clinical value

    A family of dual-activity glycosyltransferasesphosphorylases mediates mannogen turnover and virulence in Leishmania parasites

    Get PDF
    Parasitic protists belonging to the genus Leishmania synthesize the non-canonical carbohydrate reserve, mannogen, which is composed of β-1,2-mannan oligosaccharides. Here, we identify a class of dual-activity mannosyltransferase/phosphorylases (MTPs) that catalyze both the sugar nucleotide-dependent biosynthesis and phosphorolytic turnover of mannogen. Structural and phylogenic analysis shows that while the MTPs are structurally related to bacterial mannan phosphorylases, they constitute a distinct family of glycosyltransferases (GT108) that have likely been acquired by horizontal gene transfer from gram-positive bacteria. The seven MTPs catalyze the constitutive synthesis and turnover of mannogen. This metabolic rheostat protects obligate intracellular parasite stages from nutrient excess, and is essential for thermotolerance and parasite infectivity in the mammalian host. Our results suggest that the acquisition and expansion of the MTP family in Leishmania increased the metabolic flexibility of these protists and contributed to their capacity to colonize new host niches
    corecore