184 research outputs found

    Human immunodeficiency virus seroconversion presenting with acute inflammatory demyelinating polyneuropathy: a case report

    Get PDF
    <p>Abstract</p> <p>Introduction</p> <p>Acute Human Immunodeficiency Virus infection is associated with a range of neurological conditions. Guillain-Barré syndrome is a rare presentation; acute inflammatory demyelinating polyneuropathy is the commonest form of Guillain-Barré syndrome. Acute inflammatory demyelinating polyneuropathy has occasionally been reported in acute Immunodeficiency Virus infection but little data exists on frequency, management and outcome.</p> <p>Case presentation</p> <p>We describe an episode of Guillain-Barré syndrome presenting as acute inflammatory demyelinating polyneuropathy in a 30-year-old man testing positive for Immunodeficiency Virus, probably during acute seroconversion. Clinical suspicion was confirmed by cerebrospinal fluid analysis and nerve conduction studies. Rapid clinical deterioration prompted intravenous immunoglobulin therapy and early commencement of highly active anti-retroviral therapy. All symptoms resolved within nine weeks.</p> <p>Conclusion</p> <p>Unusual neurological presentations in previously fit patients are an appropriate indication for Immunodeficiency-Virus testing. Highly active anti-retroviral therapy with adequate penetration of the central nervous system should be considered as an early intervention, alongside conventional therapies such as intravenous immunoglobulin.</p

    Evolutionary relationships between Rhynchosporium lolii sp. nov. and other Rhynchosporium species on grass.

    Get PDF
    Copyright: 2013 King et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are creditedThe fungal genus Rhynchosporium (causative agent of leaf blotch) contains several host-specialised species, including R. commune (colonising barley and brome-grass), R. agropyri (couch-grass), R. secalis (rye and triticale) and the more distantly related R. orthosporum (cocksfoot). This study used molecular fingerprinting, multilocus DNA sequence data, conidial morphology, host range tests and scanning electron microscopy to investigate the relationship between Rhynchosporium species on ryegrasses, both economically important forage grasses and common wild grasses in many cereal growing areas, and other plant species. Two different types of Rhynchosporium were found on ryegrasses in the UK. Firstly, there were isolates of R. commune that were pathogenic to both barley and Italian ryegrass. Secondly, there were isolates of a new species, here named R. lolii, that were pathogenic only to ryegrass species. R. lolii was most closely related to R. orthosporum, but exhibited clear molecular, morphological and host range differences. The species was estimated to have diverged from R. orthosporum ca. 5735 years before the present. The colonisation strategy of all of the different Rhynchosporium species involved extensive hyphal growth in the sub-cuticular regions of the leaves. Finally, new species-specific PCR diagnostic tests were developed that could distinguish between these five closely related Rhynchosporium species.Peer reviewedFinal Published versio

    FONZIE: An optimized pipeline for minisatellite marker discovery and primer design from large sequence data sets

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Micro-and minisatellites are among the most powerful genetic markers known to date. They have been used as tools for a large number of applications ranging from gene mapping to phylogenetic studies and isolate typing. However, identifying micro-and minisatellite markers on large sequence data sets is often a laborious process.</p> <p>Results</p> <p>FONZIE was designed to successively 1) perform a search for markers via the external software Tandem Repeat Finder, 2) exclude user-defined specific genomic regions, 3) screen for the size and the percent matches of each relevant marker found by Tandem Repeat Finder, 4) evaluate marker specificity (i.e., occurrence of the marker as a single copy in the genome) using BLAST2.0, 5) design minisatellite primer pairs via the external software Primer3, and 6) check the specificity of each final PCR product by BLAST. A final file returns to users all the results required to amplify markers. A biological validation of the approach was performed using the whole genome sequence of the phytopathogenic fungus <it>Leptosphaeria maculans</it>, showing that more than 90% of the minisatellite primer pairs generated by the pipeline amplified a PCR product, 44.8% of which showed agarose-gel resolvable polymorphism between isolates. Segregation analyses confirmed that the polymorphic minisatellites corresponded to single-locus markers.</p> <p>Conclusion</p> <p>FONZIE is a stand-alone and user-friendly application developed to minimize tedious manual operations, reduce errors, and speed up the search for efficient minisatellite and microsatellite markers departing from whole-genome sequence data. This pipeline facilitates the integration of data and provides a set of specific primer sequences for PCR amplification of single-locus markers. FONZIE is freely downloadable at: <url>http://www.versailles-grignon.inra.fr/bioger/equipes/leptosphaeria_maculans/outils_d_analyses/fonzie</url></p

    Effector diversification within compartments of the Leptosphaeria maculans genome affected by Repeat-Induced Point mutations

    Get PDF
    Fungi are of primary ecological, biotechnological and economic importance. Many fundamental biological processes that are shared by animals and fungi are studied in fungi due to their experimental tractability. Many fungi are pathogens or mutualists and are model systems to analyse effector genes and their mechanisms of diversification. In this study, we report the genome sequence of the phytopathogenic ascomycete Leptosphaeria maculans and characterize its repertoire of protein effectors. The L. maculans genome has an unusual bipartite structure with alternating distinct guanine and cytosine-equilibrated and adenine and thymine (AT)-rich blocks of homogenous nucleotide composition. The AT-rich blocks comprise one-third of the genome and contain effector genes and families of transposable elements, both of which are affected by repeat-induced point mutation, a fungal-specific genome defence mechanism. This genomic environment for effectors promotes rapid sequence diversification and underpins the evolutionary potential of the fungus to adapt rapidly to novel host-derived constraints

    Phoma stem canker disease on oilseed rape (Brassica napus) in China is caused by Leptosphaeria biglobosa ‘brassicae’

    Get PDF
    This document is the Accepted Manuscript version of the following article: Ze Liu, Akinwunmi O. Latunde-Dada, Avice M. Hall, Bruce D. L. Fitt, ‘Phoma stem canker disease on oilseed rape (Brassica napus) in China is caused by Leptosphaeria biglobosa ‘brassicae’’, European Journal of Plant Pathology, Vol. 140(4): 841-857, December 2014. The final publication is available at Springer via: http://dx.doi.org/10.1007/s10658-014-0513-7 © Koninklijke Nederlandse Planteziektenkundige Vereniging 2014Phoma stem canker of oilseed rape (Brassica napus) is a globally important disease that is caused by the sibling ascomycete species Leptosphaeria maculans and L. biglobosa. Sixty fungal isolates obtained from oilseed rape stems with phoma stem canker disease symptoms collected from four provinces in China in 1999, 2005 and 2006 were all identified as Leptosphaeria biglobosa, not L. maculans, by PCR diagnostics based on species-specific primers. There were no differences in cultural characteristics (e.g. pigmentation and in vitro growth) between these L. biglobosa isolates from China and those of 37 proven L. biglobosa isolates from Europe or Canada. In studies using amplified fragment length polymorphism (AFLP) markers, Chinese L. biglobosa populations were genetically more similar to European L. biglobosa populations than to the more diverse Canadian L. biglobosa populations. Sequencing of gene fragments of β-tubulin, actin and the internal transcribed spacer (ITS) region of rDNA from L. biglobosa isolates from China, Europe, Australia and Canada showed a closer taxonomic similarity of Chinese L. biglobosa to the European L. biglobosa ‘brassicae’ than to Canadian L. biglobosa ‘canadensis’ or to the Australian L. biglobosa ‘occiaustralensis’ or ‘australensis’ subclades. These results suggest that the Chinese L. biglobosa population in this study is in the same subclade as European L. biglobosa ‘brassicae’ populationsPeer reviewe

    Understanding the (non-)Use of Societal Wellbeing Indicators in National Policy Development : What Can We Learn from Civil Servants? A UK Case Study

    Get PDF
    Gross Domestic Product is often used as a proxy for societal well-being in the context of policy development. Its shortcomings in this context are, however, well documented, and numerous alternative indicator sets have been developed. Despite this, there is limited evidence of widespread use of these alternative indicator sets by people working in policy areas relevant to societal wellbeing. Civil servants are an important group of indicator end-users. Better understanding their views concerning measuring societal wellbeing can support wider discussions about what factors determine indicator use and influence in policy decision-making. Taking the UK as a case study, we ask what views exist among civil servants in the UK about measuring societal well-being? To answer this question, we used a bootstrapped Q methodology, interviewing 20 civil servants to elicit their views about measuring societal well-being. Three distinct discourses emerged from our analysis: one that was concerned about the consequences of ignoring natural, social and human capital in decision making; one that emphasised opportunity and autonomy as key determinants of well-being; and one that focused on the technical aspects of measuring societal well-being. Each of these discourses has direct implications for the way that we integrate societal wellbeing into policy making and highlights the potential benefits of including end-users in indicator development and strategy

    Secondary mutations as a mechanism of cisplatin resistance in BRCA2-mutated cancers

    Get PDF
    Ovarian carcinomas with mutations in the tumour suppressor BRCA2 are particularly sensitive to platinum compounds. However, such carcinomas ultimately develop cisplatin resistance. The mechanism of that resistance is largely unknown. Here we show that acquired resistance to cisplatin can be mediated by secondary intragenic mutations in BRCA2 that restore the wild-type BRCA2 reading frame. First, in a cisplatin-resistant BRCA2-mutated breast-cancer cell line, HCC1428, a secondary genetic change in BRCA2 rescued BRCA2 function. Second, cisplatin selection of a BRCA2-mutated pancreatic cancer cell line, Capan-1 (refs 3, 4), led to five different secondary mutations that restored the wild-type BRCA2 reading frame. All clones with secondary mutations were resistant both to cisplatin and to a poly(ADP-ribose) polymerase (PARP) inhibitor (AG14361). Finally, we evaluated recurrent cancers from patients whose primary BRCA2-mutated ovarian carcinomas were treated with cisplatin. The recurrent tumour that acquired cisplatin resistance had undergone reversion of its BRCA2 mutation. Our results suggest that secondary mutations that restore the wild-type BRCA2 reading frame may be a major clinical mediator of acquired resistance to platinum-based chemotherapy

    The Predicted Secretome of the Plant Pathogenic Fungus Fusarium graminearum: A Refined Comparative Analysis

    Get PDF
    The fungus Fusarium graminearum forms an intimate association with the host species wheat whilst infecting the floral tissues at anthesis. During the prolonged latent period of infection, extracellular communication between live pathogen and host cells must occur, implying a role for secreted fungal proteins. The wheat cells in contact with fungal hyphae subsequently die and intracellular hyphal colonisation results in the development of visible disease symptoms. Since the original genome annotation analysis was done in 2007, which predicted the secretome using TargetP, the F. graminearum gene call has changed considerably through the combined efforts of the BROAD and MIPS institutes. As a result of the modifications to the genome and the recent findings that suggested a role for secreted proteins in virulence, the F. graminearum secretome was revisited. In the current study, a refined F. graminearum secretome was predicted by combining several bioinformatic approaches. This strategy increased the probability of identifying truly secreted proteins. A secretome of 574 proteins was predicted of which 99% was supported by transcriptional evidence. The function of the annotated and unannotated secreted proteins was explored. The potential role(s) of the annotated proteins including, putative enzymes, phytotoxins and antifungals are discussed. Characterisation of the unannotated proteins included the analysis of Pfam domains and features associated with known fungal effectors, for example, small size, cysteine-rich and containing internal amino acid repeats. A comprehensive comparative genomic analysis involving 57 fungal and oomycete genomes revealed that only a small number of the predicted F. graminearum secreted proteins can be considered to be either species or sequenced strain specific

    Horizontal Transfer of a Nitrate Assimilation Gene Cluster and Ecological Transitions in Fungi: A Phylogenetic Study

    Get PDF
    High affinity nitrate assimilation genes in fungi occur in a cluster (fHANT-AC) that can be coordinately regulated. The clustered genes include nrt2, which codes for a high affinity nitrate transporter; euknr, which codes for nitrate reductase; and NAD(P)H-nir, which codes for nitrite reductase. Homologs of genes in the fHANT-AC occur in other eukaryotes and prokaryotes, but they have only been found clustered in the oomycete Phytophthora (heterokonts). We performed independent and concatenated phylogenetic analyses of homologs of all three genes in the fHANT-AC. Phylogenetic analyses limited to fungal sequences suggest that the fHANT-AC has been transferred horizontally from a basidiomycete (mushrooms and smuts) to an ancestor of the ascomycetous mold Trichoderma reesei. Phylogenetic analyses of sequences from diverse eukaryotes and eubacteria, and cluster structure, are consistent with a hypothesis that the fHANT-AC was assembled in a lineage leading to the oomycetes and was subsequently transferred to the Dikarya (Ascomycota+Basidiomycota), which is a derived fungal clade that includes the vast majority of terrestrial fungi. We propose that the acquisition of high affinity nitrate assimilation contributed to the success of Dikarya on land by allowing exploitation of nitrate in aerobic soils, and the subsequent transfer of a complete assimilation cluster improved the fitness of T. reesei in a new niche. Horizontal transmission of this cluster of functionally integrated genes supports the “selfish operon” hypothesis for maintenance of gene clusters
    corecore