239 research outputs found

    High-level diversity of tailed phages, eukaryote-associated viruses, and virophage-like elements in the metaviromes of Antarctic soils

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    The metaviromes of two distinct Antarctic hyperarid desert soil communities have been characterized. Hypolithic communities, cyanobacterium-dominated assemblages situated on the ventral surfaces of quartz pebbles embedded in the desert pavement, showed higher virus diversity than surface soils, which correlated with previous bacterial community studies. Prokaryotic viruses (i.e., phages) represented the largest viral component (particularly Mycobacterium phages) in both habitats, with an identical hierarchical sequence abundance of families of tailed phages (Siphoviridae>Myoviridae>Podoviridae). No archaeal viruses were found. Unexpectedly, cyanophages were poorly represented in both metaviromes and were phylogenetically distant from currently characterized cyanophages. Putative phage genomes were assembled and showed a high level of unaffiliated genes, mostly from hypolithic viruses. Moreover, unusual gene arrangements in which eukaryotic and prokaryotic virus-derived genes were found within identical genome segments were observed. Phycodnaviridae and Mimiviridae viruses were the second-mostabundant taxa and more numerous within open soil. Novel virophage-like sequences (within the Sputnik clade) were identified. These findings highlight high-level virus diversity and novel species discovery potential within Antarctic hyperarid soils and may serve as a starting point for future studies targeting specific viral groups.IS

    Unique aliphatic amidase from a psychrotrophic and haloalkaliphilic nesterenkonia isolate

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    Nesterenkonia strain AN1 was isolated from a screening program for nitrile- and amide-hydrolyzing microorganisms in Antarctic desert soil samples. Strain AN1 showed significant 16S rRNA sequence identity to known members of the genus. Like known Nesterenkonia species, strain AN1 was obligately alkaliphilic (optimum environmental pH, 9 to 10) and halotolerant (optimum environmental Na+ content, 0 to 15% [wt/vol]) but was also shown to be an obligate psychrophile with optimum growth at approximately 21Β°C

    Misregulated E-Cadherin Expression Associated with an Aggressive Brain Tumor Phenotype

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    BACKGROUND: Cadherins are essential components of the adherens junction complexes that mediate cell-cell adhesion and regulate cell motility. During tissue morphogenesis, changes in cadherin expression (known as cadherin switching) are a common mechanism for altering cell fate. Cadherin switching is also common during epithelial tumor progression, where it is thought to promote tumor invasion and metastasis. E-cadherin is the predominant cadherin expressed in epithelial tissues, but its expression is very limited in normal brain. METHODOLOGY/PRINCIPAL FINDINGS: We identified E-cadherin expression in a retrospective series of glioblastomas exhibiting epithelial or pseudoepithelial differentiation. Unlike in epithelial tissues, E-cadherin expression in gliomas correlated with an unfavorable clinical outcome. Western blotting of two panels of human GBM cell lines propagated either as xenografts in nude mice or grown under conventional cell culture conditions confirmed that E-cadherin expression is rare. However, a small number of xenograft lines did express E-cadherin, its expression correlating with increased invasiveness when the cells were implanted orthotopically in mouse brain. In the conventionally cultured SF767 glioma cell line, E-cadherin expression was localized throughout the plasma membrane rather than being restricted to areas of cell-cell contact. ShRNA knockdown of E-cadherin in these cells resulted in decreased proliferation and migration in vitro. CONCLUSIONS/SIGNIFICANCE: Our data shows an unexpected correlation between the abnormal expression of E-cadherin in a subset of GBM tumor cells and the growth and migration of this aggressive brain tumor subtype

    Engineering pyruvate decarboxylase-mediated ethanol production in the thermophilic host Geobacillus thermoglucosidasius

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    Abstract This study reports the expression, purification and kinetic characterization of a PDC from may be the result of ineffective transcription / translation coupling

    Reassurance Policing and Signal Crimes

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    A reassurance function for policing was first considered by American psychologist Charles Bahn (1974: 338) as β€œfeelings of safety that a citizen experiences when he knows that a police officer or patrol car is nearby.” This idea was taken forward in Britain by Martin Innes and colleagues in the early 2000s through the development of a signal crimes perspective. At this time, British policing implemented a National Reassurance Policing Programme (NRPP) where local policing priorities were decided through consultation with local communities. The impact of reassurance policing has since spread and the approach has also been considered in Australia, Belgium, the Netherlands, and Sweden. In this entry, the background to reassurance policing is considered with particular reference to the work of Charles Bahn and Martin Innes and colleagues. The development of a policy of reassurance policing in Britain is also examined. The successes and limitations of the approach are considered and three main issues identified: that reassurance needs to be a consideration for all policing; that increases in visible patrol need to be questioned (especially at a time of budget restraint); and that reassurance policing has the potential to be a model of democratic policing, but only if consultation is truly inclusive, for instance, including those that have been victimized and groups that have been targets of police activity such as young people, the homeless, and other minority and marginalized groups

    Solution fibre spinning technique for the fabrication of tuneable decellularised matrix-laden fibres and fibrous micromembranes.

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    UNLABELLED: Recreating tissue-specific microenvironments of the extracellular matrix (ECM) in vitro is of broad interest for the fields of tissue engineering and organ-on-a-chip. Here, we present biofunctional ECM protein fibres and suspended membranes, with tuneable biochemical, mechanical and topographical properties. This soft and entirely biologic membrane scaffold, formed by micro-nano-fibres using low voltage electrospinning, displays three unique characteristics for potential cell culture applications: high-content of key ECM proteins, single-layered mesh membrane, and flexibility for in situ integration into a range of device setups. Extracellular matrix (ECM) powder derived from urinary bladder, was used to fabricate the ECM-laden fibres and membranes. The highest ECM concentration in the dry protein fibre was 50β€―wt%, with the rest consisting of gelatin. Key ECM proteins, including collagen IV, laminin, and fibronectin, were shown to be preserved post the biofabrication process. The single fibre tensile Young's modulus can be tuned for over two orders of magnitude between ∼600β€―kPa and 50β€―MPa depending on the ECM content. Combining the fibre mesh printing with 3D printed or microfabricated structures, culture devices were constructed for endothelial layer formation, and a trans-membrane co-culture formed by glomerular cell types of podocytes and glomerular endothelial cells, demonstrating feasibility of the membrane culture. Our cell culture observation points to the importance of membrane mechanical property and re-modelling ability as a factor for soft membrane-based cell cultures. The ECM-laden fibres and membranes presented here would see potential applications in in vitro assays, and tailoring structure and biological functions of tissue engineering scaffolds. STATEMENT OF SIGNIFICANCE: Recreating tissue-specific microenvironments of the extracellular matrix (ECM) is of broad interest for the fields of tissue engineering and organ-on-a-chip. Both the biochemical and biophysical signatures of the engineered ECM interplay to affect cell response. Currently, there are limited biomaterials processing methods which allow to design ECM membrane properties flexibly and rapidly. Solvents and additives used in many existing processes also induced unwanted ECM protein degradation and toxic residues. This paper presents a solution fibre spinning technique, where careful selection of the solution combination led to well-preserved ECM proteins with tuneable composition. This technique also provides a highly versatile approach to fabricate ECM fibres and membranes, leading to designable fibre Young's modulus for over two orders of magnitude.This work is supported by the Engineering and Physical Sciences Research Council (EPSRC) UK (EP/M018989/1) and European Research Council (ERC-StG, 758865). The authors thank the studentship and funding supports from the EPSRC DTA (Z.L.), the WD Armstrong Trust (I.M.L), the Swiss National Science Foundation (P300P2_171219) and the Centre for Misfolding Disease of the University of Cambridge (F.S.R.)

    Niche-dependent genetic diversity in Antarctic metaviromes

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    The metaviromes from 2 different Antarctic terrestrial soil niches have been analyzed. Both hypoliths (microbial assemblages beneath transluscent rocks) and surrounding open soils showed a high level diversity of tailed phages, viruses of algae and amoeba, and virophage sequences. Comparisons of other global metaviromes with the Antarctic libraries showed a niche-dependent clustering pattern, unrelated to the geographical origin of a given metavirome. Within the Antarctic open soil metavirome, a putative circularly permuted, Β»42kb dsDNA virus genome was annotated, showing features of a temperate phage possessing a variety of conserved protein domains with no significant taxonomic affiliations in current databases.National Research Foundation (South Africa) and the Genomics Research Institute of the University of Pretoria (South Africa).http://www.tandfonline.com/loi/kbac202015-12-31hb201

    Metagenomic analysis of the viral community in Namib desert hypoliths

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    Hypolithic microbial communities are specialized desert communities inhabiting the underside of translucent rocks where they are sheltered from harsh environmental conditions. Here, we present the first study of the viral fraction of these communities isolated from the hyperarid Namib Desert (coastal South Western Africa). Using next-generation sequencing of the isolated viral fraction, the diversity and taxonomic composition of hypolith communities was mapped and a functional assessment of the sequences determined. Phylotypic analysis showed that bacteriophages belonging to the order Caudovirales with the family Siphoviridae were most prevalent. A major fraction of phage types was linked by database homologies to Bacillus or Geobacillus sp. as a host. Phylogenetic analyses of terL and phoH marker genes indicated that many of the sequences were novel and distinct from known isolates and environments, an observation supported by the class distribution of identified ribonucleotide reductases. The composition of the viral hypolith fraction was not completely consistent with Namib hypolith phylotypic surveys, in which the cyanobacterial genus Chroococcidiopsis was found to be dominant. This could be attributed to lacking sequence information about hypolith viruses/bacteria in public databases or the hypothesis that hypolithic communities actively recruit viruses from the surrounding open soil in which Bacillaceae-infecting phages are more commonly found.http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1462-2920hb201

    Care of older people and people requiring palliative care with COVID-19: guidance from the Australian National COVID-19 Clinical Evidence Taskforce.

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    INTRODUCTION: Older people living with frailty and/or cognitive impairment who have coronavirus disease 2019 (COVID-19) experience higher rates of critical illness. There are also people who become critically ill with COVID-19 for whom a decision is made to take a palliative approach to their care. The need for clinical guidance in these two populations resulted in the formation of the Care of Older People and Palliative Care Panel of the National COVID-19 Clinical Evidence Taskforce in June 2020. This specialist panel consists of nursing, medical, pharmacy and allied health experts in geriatrics and palliative care from across Australia. MAIN RECOMMENDATIONS: The panel was tasked with developing two clinical flow charts for the management of people with COVID-19 who are i) older and living with frailty and/or cognitive impairment, and ii) receiving palliative care for COVID-19 or other underlying illnesses. The flow charts focus on goals of care, communication, medication management, escalation of care, active disease-directed care, and managing symptoms such as delirium, anxiety, agitation, breathlessness or cough. The Taskforce also developed living guideline recommendations for the care of adults with COVID-19, including a commentary to discuss special considerations when caring for older people and those requiring palliative care. CHANGES IN MANAGEMENT AS RESULT OF THE GUIDELINE: The practice points in the flow charts emphasise quality clinical care, with a focus on addressing the most important challenges when caring for older individuals and people with COVID-19 requiring palliative care. The adult recommendations contain additional considerations for the care of older people and those requiring palliative care
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