40 research outputs found

    Viral discovery and diversity in trypanosomatid protozoa with a focus on relatives of the human parasite <i>Leishmania</i>.

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    Knowledge of viral diversity is expanding greatly, but many lineages remain underexplored. We surveyed RNA viruses in 52 cultured monoxenous relatives of the human parasite &lt;i&gt;Leishmania&lt;/i&gt; ( &lt;i&gt;Crithidia&lt;/i&gt; and &lt;i&gt;Leptomonas&lt;/i&gt; ), as well as plant-infecting &lt;i&gt;Phytomonas&lt;/i&gt; &lt;i&gt;Leptomonas pyrrhocoris&lt;/i&gt; was a hotbed for viral discovery, carrying a virus (Leptomonas pyrrhocoris ostravirus 1) with a highly divergent RNA-dependent RNA polymerase missed by conventional BLAST searches, an emergent clade of tombus-like viruses, and an example of viral endogenization. A deep-branching clade of trypanosomatid narnaviruses was found, notable as &lt;i&gt;Leptomonas seymouri&lt;/i&gt; bearing Narna-like virus 1 (LepseyNLV1) have been reported in cultures recovered from patients with visceral leishmaniasis. A deep-branching trypanosomatid viral lineage showing strong affinities to bunyaviruses was termed " &lt;i&gt;Leishbunyavirus&lt;/i&gt; " (LBV) and judged sufficiently distinct to warrant assignment within a proposed family termed " &lt;i&gt;Leishbunyaviridae&lt;/i&gt; " Numerous relatives of trypanosomatid viruses were found in insect metatranscriptomic surveys, which likely arise from trypanosomatid microbiota. Despite extensive sampling we found no relatives of the totivirus &lt;i&gt;Leishmaniavirus&lt;/i&gt; (LRV1/2), implying that it was acquired at about the same time the &lt;i&gt;Leishmania&lt;/i&gt; became able to parasitize vertebrates. As viruses were found in over a quarter of isolates tested, many more are likely to be found in the &gt;600 unsurveyed trypanosomatid species. Viral loss was occasionally observed in culture, providing potentially isogenic virus-free lines enabling studies probing the biological role of trypanosomatid viruses. These data shed important insights on the emergence of viruses within an important trypanosomatid clade relevant to human disease

    Alien Plants Introduced by Different Pathways Differ in Invasion Success: Unintentional Introductions as a Threat to Natural Areas

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    BACKGROUND: Understanding the dimensions of pathways of introduction of alien plants is important for regulating species invasions, but how particular pathways differ in terms of post-invasion success of species they deliver has never been rigorously tested. We asked whether invasion status, distribution and habitat range of 1,007 alien plant species introduced after 1500 A.D. to the Czech Republic differ among four basic pathways of introduction recognized for plants. PRINCIPAL FINDINGS: Pathways introducing alien species deliberately as commodities (direct release into the wild; escape from cultivation) result in easier naturalization and invasion than pathways of unintentional introduction (contaminant of a commodity; stowaway arriving without association with it). The proportion of naturalized and invasive species among all introductions delivered by a particular pathway decreases with a decreasing level of direct assistance from humans associated with that pathway, from release and escape to contaminant and stowaway. However, those species that are introduced via unintentional pathways and become invasive are as widely distributed as deliberately introduced species, and those introduced as contaminants invade an even wider range of seminatural habitats. CONCLUSIONS: Pathways associated with deliberate species introductions with commodities and pathways whereby species are unintentionally introduced are contrasting modes of introductions in terms of invasion success. However, various measures of the outcome of the invasion process, in terms of species' invasion success, need to be considered to accurately evaluate the role of and threat imposed by individual pathways. By employing various measures we show that invasions by unintentionally introduced plant species need to be considered by management as seriously as those introduced by horticulture, because they invade a wide range of seminatural habitats, hence representing even a greater threat to natural areas

    TRY plant trait database – enhanced coverage and open access

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    Plant traits—the morphological, anatomical, physiological, biochemical and phenological characteristics of plants—determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait‐based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits—almost complete coverage for ‘plant growth form’. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait–environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

    TRY plant trait database – enhanced coverage and open access

    Get PDF
    Plant traits - the morphological, anatomical, physiological, biochemical and phenological characteristics of plants - determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait‐based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits - almost complete coverage for ‘plant growth form’. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait–environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

    Sensitivity analysis for an almost periodic unsteady flow problem; application to turbo-machinery modelling

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    “Centre of research and experimental development of reliable energy production” TE01020068 of the Technology Agency of the Czech Republic

    Myocarditis - Diagnosis, treatment, use of cardiac magnetic resonance imaging and case report of a young athlete

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    Myocarditis is defined as the inflammation of the myocardium. It is an illness with many different faces at the  time of clinical presentation or suspicion. The clinical presentation is highly variable ranging from asymptomatic to rapidly progressive and fatal congestive heart failure. Myocarditis accounts for 2-42% of sudden cardiac deaths in young adults based on the autopsy data (1). Use of cardiac magnetic resonance expanded the possibilities of the non-invasive assessment of myocardial inflammation and opened new ways for risk stratification of patients
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