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Funding: Medical Research Council (G1100139) The hepatitis C virus RNA genome possesses a variety of conserved structural elements, in both coding and non-coding regions, that are important for viral replication. These elements are known or predicted to modulate key life cycle events, such as translation and genome replication, some involving conformational changes induced by long-range RNA–RNA interactions. One such element is SLVI, a stem-loop (SL) structure located towards the 5′ end of the core protein-coding region. This element forms an alternative RNA–RNA interaction with complementary sequences in the 5′ untranslated regions that are independently involved in the binding of the cellular microRNA 122 (miR122). The switch between ‘open’ and ‘closed’ structures involving SLVI has previously been proposed to modulate translation, with lower translation efficiency associated with the ‘closed’ conformation. In the current study, we have used selective 2′-hydroxyl acylation analysed by primer extension to validate this RNA–RNA interaction in the absence and presence of miR122. We show that the long-range association (LRA) only forms in the absence of miR122, or otherwise requires the blocking of miR122 binding combined with substantial disruption of SLVI. Using site-directed mutations introduced to promote open or closed conformations of the LRA we demonstrate no correlation between the conformation and the translation phenotype. In addition, we observed no influence on virus replication compared to unmodified genomes. The presence of SLVI is well-documented to suppress translation, but these studies demonstrate that this is not due to its contribution to the LRA. We conclude that, although there are roles for SLVI in translation, the LRA is not a riboswitch regulating the translation and replication phenotypes of the virus. Publisher PDF

Decay-accelerating factor (CD55), a regulator of the alternative and classical pathways of complement activation, is expressed on all serum-exposed cells. It is used by pathogens, including many enteroviruses and uropathogenic Escherichia coli, as a receptor prior to infection. We describe the x-ray structure of a pathogen-binding fragment of human CD55 at 1.7 A resolution containing two of the three domains required for regulation of human complement. We have used mutagenesis to map biological functions onto the molecule; decay-accelerating activity maps to a single face of the molecule, whereas bacterial and viral pathogens recognize a variety of different sites on CD55.

BACKGROUND: Poorly controlled asthma and preventable exacerbations place a significant strain on healthcare, often requiring additional medications, hospital stays or treatment in the emergency department.Long-acting beta2-agonists (LABA) are the preferred add-on treatment for adults with asthma whose symptoms are not well controlled on inhaled corticosteroids (ICS), but have important safety concerns in asthma. Long-acting muscarinic antagonists (LAMA) have confirmed efficacy in chronic obstructive pulmonary disease and are now being considered as an alternative add-on therapy for people with uncontrolled asthma. OBJECTIVES: To assess the efficacy and safety of adding a LAMA to ICS compared with adding a LABA for adults whose asthma is not well controlled on ICS alone. SEARCH METHODS: We searched the Cochrane Airways Group's Specialised Register (CAGR) from inception to April 2015, and imposed no restriction on language of publication. We searched additional resources to pick up unpublished studies, including ClinicalTrials.gov, World Health Organization trials portal, reference lists of primary studies and existing reviews, and manufacturers' trial registries. The most recent search was conducted in April 2015. SELECTION CRITERIA: We searched for parallel and cross-over RCTs in which adults whose asthma was not well controlled with ICS alone were randomised to receive LAMA add-on or LABA add-on for at least 12 weeks. DATA COLLECTION AND ANALYSIS: Two review authors independently screened the electronic and additional searches and extracted data from study reports. We used Covidence for duplicate screening, extraction of study characteristics and numerical data, and risk of bias ratings.The pre-specified primary outcomes were exacerbations requiring oral corticosteroids (OCS), quality of life and serious adverse events. MAIN RESULTS: We included eight studies meeting the inclusion criteria, but four double-blind, double-dummy studies of around 2000 people dominated the analyses. These four trials were between 14 and 24 weeks long, all comparing tiotropium (usually Respimat) with salmeterol on top of medium doses of ICS.Studies reporting exacerbations requiring OCS showed no difference between the two add-ons, but our confidence in the effect was low due to inconsistency between studies and because the confidence intervals (CI) included significant benefit of either treatment (odds ratio (OR) 1.05, 95% CI 0.50 to 2.18; 1753 participants; 3 studies); three more people per 1000 might have an exacerbation on LAMA, but the CIs ranged from 29 fewer to 61 more. Imprecision was also an issue for serious adverse events and exacerbations requiring hospital admission, rated low (serious adverse events) and very low quality (exacerbations requiring hospital admission), because there were so few events in the analyses.People taking LAMA scored slightly worse on two scales measuring quality of life (Asthma Quality of Life Questionnaire; AQLQ) and asthma control (Asthma Control Questionnaire; ACQ); the evidence was rated high quality but the effects were small and unlikely to be clinically significant (AQLQ: mean difference (MD) -0.12, 95% CI -0.18 to -0.05; 1745 participants; 1745; 4 studies; ACQ: MD 0.06, 95% CI 0.00 to 0.13; 1483 participants; 3 studies).There was some evidence to support small benefits of LAMA over LABA on lung function, including on our pre-specified preferred measure trough forced expiratory volume in one second (FEV1) (MD 0.05 L, 95% CI 0.01 to 0.09; 1745 participants, 4 studies). However, the effects on other measures varied, and it is not clear whether the magnitude of the differences were clinically significant.More people had adverse events on LAMA but the difference with LABA was not statistically significant. AUTHORS' CONCLUSIONS: Direct evidence of LAMA versus LABA as add-on therapy is currently limited to studies of less than six months comparing tiotropium (Respimat) to salmeterol, and we do not know how they compare in terms of exacerbations and serious adverse events. There was moderate quality evidence that LAMAs show small benefits over LABA on some measures of lung function, and high quality evidence that LABAs are slightly better for quality of life, but the differences were all small. Given the much larger evidence base for LABA versus placebo for people whose asthma is not well controlled on ICS, the current evidence is not strong enough to say that LAMA can be substituted for LABA as add-on therapy.The results of this review, alongside pending results from related reviews assessing the use of LAMA in other clinical scenarios, will help to define the role of these drugs in asthma and it is important that they be updated as results from ongoing and planned trials emerge.

Insect pollinators of crops and wild plants are under threat globally and their decline or loss could have profound economic and environmental consequences. Here, we argue that multiple anthropogenic pressures – including land-use intensification, climate change, and the spread of alien species and diseases – are primarily responsible for insect-pollinator declines. We show that a complex interplay between pressures (eg lack of food sources, diseases, and pesticides) and biological processes (eg species dispersal and interactions) at a range of scales (from genes to ecosystems) underpins the general decline in insect-pollinator populations. Interdisciplinary research on the nature and impacts of these interactions will be needed if human food security and ecosystem function are to be preserved. We highlight key areas that require research focus and outline some practical steps to alleviate the pressures on pollinators and the pollination services they deliver to wild and crop plants.

Long-acting beta(2)-agonists and inhaled corticosteroids can be used as maintenance therapy by patients with moderate to severe chronic obstructive pulmonary disease. These interventions are often taken together in a combination inhaler. However, the relative added value of the two individual components is unclear.

Up to recent times interest has concentrated mainly on ‘implicit methods’ for the numerical solution of the initial-boundary value problem by finite-difference/finite-element methods. However, the increasing availability of parallel computers enabled the ‘explicit methods’ of solution to become competitive, since, besides their simplicity, they exhibit an inherent parallelism as the solution can be obtained at many points simultaneously. This paper investigates the applicability of a new group explicit method to parallel processing and the work is concentrated on the selection of a suitable algorithm which can effectively utilize the processing potential of a MIMD parallel ‘testbed’ while it remains stable producing highly accurate results.

Fifty years ago health care was a private matter between a physician and his patient. Doctors practiced medicine; people could and did pay for their own health care; and legislators did not need to concern themselves much with health problems. In the meantime, instigated by a massive scientific knowledge explosion, we have spent billions on monstrous complexes to house ultramodern equipment and technology to fight acute, dreaded diseases. Doctors, who once treated human body as an entity, are so specialized that none seems to know any more that the head bone is still indirectly connected to the great toe. People, who incidentally are plagued with essentially the same chronic maladies that visited their predecessors five decades ago, are in real trouble if their complaint is simply a boil on the backside. First they must determine who specializes in this particular area. Next they are lucky if they can obtain an appointment before the boil bursts. Finally, they probably cannot afford to pay for the services rendered. The lawmaker steps in and pours more money into erecting more buildings and providing more specialists. We will not solve the dissonance between the mutually dependent group if we isolate ourselves, forgetting to listen, forgetting to educate, forgetting to communicate. Let me close with Sir William Osler's metaphor: How common the experience to enter a cold cheerless room in which the fire in the grate has died down, not from lack of coal, not because the coal was not alight, but the bits, large and small, falling away from each other have gradually become dark and cold. Break them with a poker, get them together, and what a change in a few minutes.

SUMMARY Leucocyte alkaline phosphatasc (LAP) levels have been compared in neutrophil polymorphs in bone marrow and blood in the rat, using a quantitative enzyme cytochemical technique. It has been shown that LAP levels are higher in bone marrow than blood, both in normal animals and those with experimentally-induced local inflammatory lesions. In the latter group both bone marrow and blood LAP levels were higher than in controls; blood levels rose because of the outpouring of cells with moderately high LAP levels into the blood and marrow levels rose because only cells with very high LAP levels remained. The inverse relationship between rieutrophil age and alkaline phosphatase content, previously demonstrated in the peripheral blood of the rat, has also been shown to exist in the bone marrow.

The surface of untreated wool has been investigated using x-ray photoelectron spec troscopy (XPS) and static secondary ion mass spectrometry (SSIMS). The wool surface is covered in a thin layer of lipid estimated to be approximately 0.9 nm thick. Mass spectral peaks are consistent with the presence in the lipid layer of saturated C20, C21, and hydroxylated C21 fatty acids, presumably bound as esters. This lipid layer can be partially, but not completely, removed by treatment with potassium tert-butoxide in tert-butanol or potassium hydroxide, reagents that cause oxidation of the surface cys tine. XPS indicates that the surface protein (epicuticle) is rich in sulfur, suggesting a half-cystine content of about 35%.