255 research outputs found

    Description of Bathysciola liqueana n. sp. from the central Pyrenees. Designation of lectotypes and distribution data for species of the B. meridionalis group (Jacquelin du Val, 1854) (Insecta, Coleoptera, Leiodidae, Cholevinae, Leptodirini)

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    Se describe una nueva especie del género Bathysciola Jeannel, 1910 (B. liqueana sp. n.) que pertenece al grupo "meridionalis". Se ha encontrado en medio subterráneo, en la Grotte de Liqué, macizo de Larroque, Moulis, Ariège, Francia. La especie más similar es Bathysciola meridionalis (Jacquelin du Val, 1854), también descubierta en Ariège. Los caracteres distintivos se encuentran básicamente en el edeago: es corto, ancho, con el ápice redondeado en B. liqueana sp. n. y largo, estrecho, con el ápice puntiagudo en B. meridionalis. Se discute su posición taxonómica y se completa el estudio con ilustraciones de las estructuras que permiten distinguir estos táxones, así como también los datos de distribución de que se dispone, incluyendo también a B. finismillennii Fresneda & Salgado, 2006. Se designan los lectotipos de B. meridionalis y de B. nitidula Normand, 1907. Palabras clave: Coleoptera, Leiodidae, Bathysciola, Grupo "meridionalis", Pirineos.Se describe una nueva especie del género Bathysciola Jeannel, 1910 (B. liqueana sp. n.) que pertenece al grupo "meridionalis". Se ha encontrado en medio subterráneo, en la Grotte de Liqué, macizo de Larroque, Moulis, Ariège, Francia. La especie más similar es Bathysciola meridionalis (Jacquelin du Val, 1854), también descubierta en Ariège. Los caracteres distintivos se encuentran básicamente en el edeago: es corto, ancho, con el ápice redondeado en B. liqueana sp. n. y largo, estrecho, con el ápice puntiagudo en B. meridionalis. Se discute su posición taxonómica y se completa el estudio con ilustraciones de las estructuras que permiten distinguir estos táxones, así como también los datos de distribución de que se dispone, incluyendo también a B. finismillennii Fresneda & Salgado, 2006. Se designan los lectotipos de B. meridionalis y de B. nitidula Normand, 1907. Palabras clave: Coleoptera, Leiodidae, Bathysciola, Grupo "meridionalis", Pirineos.We describe a new species of the genus Bathysciola Jeannel, 1910 (B. liqueana n. sp.) belonging to the "meridionalis" group. It was collected in a subterranean environment, in Liqué cave, Larroque massif, Moulis, Ariège, France. The closest species is Bathysciola meridionalis (Jacquelin du Val, 1854), also known from Ariège. The new species differs mainly in morphological characteristics of the aedeagus: short, wide, with rounded apex in B. liqueana n. sp. whereas it is long, narrow, with pointed apex in B. meridionalis. We discuss the taxonomical position of the new species and provide illustrations of structures showing the differences between the two species, along with distribution data, including for B. finismillennii Fresneda & Salgado, 2006. We designate lectotypes of B. meridionalis and B. nitidula Normand, 1907. Key words: Coleoptera, Leiodidae, Bathysciola, "meridionalis" group, Pyrenees

    Una nueva especie troglobiomorfa de Trechus Clairville, 1806 y evidencias de colonizaciones múltiples del medio subterráneo de los montes cantábricos (Coleoptera, Carabidae, Trechinae)

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    Se describe Trechus (Trechus) valenzuelai sp. n. de los montes cantábricos en España: Sierra de Cuera, en Asturias. La especie se ha encontrado en el medio subterráneo, en cuevas y dolinas. El estudio morfológico revela que se debe situar como especie hermana de Trechus escalerae Abeille de Perrin, 1903, en el clado de T. saxicola Putzeys, 1870. Se ha encontrado una sinapomorfía en los edeagos de T. escalerae y T. valenzuelai sp. n. que se describe e ilustra: el endofalo tiene una fanera con forma de porra, alargada, robusta y muy esclerotizada, en cuya base se encuentra un saco membranoso recubierto por espínulas. Se discute la taxonomía y la sistemática, y se aportan ilustraciones de las estructuras que muestran las diferencias entre T. escalerae y T. valenzuelai sp. n.; también se proporcionan datos relativos a la distribución y la biogeografía, así como hipótesis sobre los procesos de especiación, tomando como base de argumentación los datos moleculares previamente publicados, la estructura geológica de la región y los acontecimientos paleoclimáticos; se postulan procesos de colonización activa, simultáneos e independientes, del medio subterráneo. Se designa el lectotipo de T. escalerae.A new troglobiomorphic Trechus Clairville, 1806 and evidence of multiple colonizations in the subterranean environment of the Cantabrian mountains (Coleoptera, Carabidae, Trechinae) We describe Trechus (Trechus) valenzuelai n. sp. from the Cantabrian area of Spain: Sierra de Cuera, Asturias. The species was collected in the subterranean environment, in caves and dolines. Morphological examination revealed that the new species is sister to Trechus escalerae Abeille de Perrin, 1903 within the T. saxicola clade. A synapomorphy of the male genitalia, shared by T. valenzuelai n. sp. and T. escalerae, is described and illustrated: the endophallus has a sclerotised piece shaped like a club, elongated, robust, strongly sclerotised and with a membranous sac covered with small spicules at the base. We discuss the taxonomy of the new species and provide illustrations of structures showing the differences between T. escalerae and T. valenzuelai n. sp., along with biogeographical and distributional data and hypotheses regarding the speciation events based on previously pubished molecular data, and the geological structure and the palaeoclimatology of their geographical area. We hypothesize that in this clade, the colonization of the subterranean environment was the result of multiple, independent and simultaneous colonization processes. A lectotype is designated for T. escalerae.Se describe Trechus (Trechus) valenzuelai sp. n. de los montes cantábricos en España: Sierra de Cuera, en Asturias. La especie se ha encontrado en el medio subterráneo, en cuevas y dolinas. El estudio morfológico revela que se debe situar como especie hermana de Trechus escalerae Abeille de Perrin, 1903, en el clado de T. saxicola Putzeys, 1870. Se ha encontrado una sinapomorfía en los edeagos de T. escalerae y T. valenzuelai sp. n. que se describe e ilustra: el endofalo tiene una fanera con forma de porra, alargada, robusta y muy esclerotizada, en cuya base se encuentra un saco membranoso recubierto por espínulas. Se discute la taxonomía y la sistemática, y se aportan ilustraciones de las estructuras que muestran las diferencias entre T. escalerae y T. valenzuelai sp. n.; también se proporcionan datos relativos a la distribución y la biogeografía, así como hipótesis sobre los procesos de especiación, tomando como base de argumentación los datos moleculares previamente publicados, la estructura geológica de la región y los acontecimientos paleoclimáticos; se postulan procesos de colonización activa, simultáneos e independientes, del medio subterráneo. Se designa el lectotipo de T. escalerae

    Mechanism of completion of peptidyltransferase centre assembly in eukaryotes.

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    During their final maturation in the cytoplasm, pre-60S ribosomal particles are converted to translation-competent large ribosomal subunits. Here, we present the mechanism of peptidyltransferase centre (PTC) completion that explains how integration of the last ribosomal proteins is coupled to release of the nuclear export adaptor Nmd3. Single-particle cryo-EM reveals that eL40 recruitment stabilises helix 89 to form the uL16 binding site. The loading of uL16 unhooks helix 38 from Nmd3 to adopt its mature conformation. In turn, partial retraction of the L1 stalk is coupled to a conformational switch in Nmd3 that allows the uL16 P-site loop to fully accommodate into the PTC where it competes with Nmd3 for an overlapping binding site (base A2971). Our data reveal how the central functional site of the ribosome is sculpted and suggest how the formation of translation-competent 60S subunits is disrupted in leukaemia-associated ribosomopathies.Bloodwise, MRC, Wellcome Trus

    Tests at 2K of the beta 0.35 spoke cryomodule prototype with the MTCA.4-based Low Level RF system prototype for the MYRRHA R&D

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    Within the framework of the first phase of MYRRHA (Multi-purpose hYbrid Research Reactor for High-tech Applications) project, called MINERVA, IJCLab was in charge of a fully equipped Spoke cryomodule prototype development, tested at 2K. It integrates two superconducting single spoke cavities, the RF power couplers and the Cold Tuning Systems associated. On the control side, a MTCA.4-based Low Level Radio Frequency (LLRF) system prototype and the Software/EPICS developments has been realized by IJCLab and the SCK CEN in collaboration with the company IOxOS Technologies. The final version of the global system and the results of the tests at 2K will show with some perspectives.Comment: Poster pr\'esent\'e au LLRF Workshop 2023 (LLRF2023, arXiv : 2310.03199

    HDL Interfere with the Binding of T Cell Microparticles to Human Monocytes to Inhibit Pro-Inflammatory Cytokine Production

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    BACKGROUND: Direct cellular contact with stimulated T cells is a potent mechanism that induces cytokine production in human monocytes in the absence of an infectious agent. This mechanism is likely to be relevant to T cell-mediated inflammatory diseases such as rheumatoid arthritis and multiple sclerosis. Microparticles (MP) generated by stimulated T cells (MPT) display similar monocyte activating ability to whole T cells, isolated T cell membranes, or solubilized T cell membranes. We previously demonstrated that high-density lipoproteins (HDL) inhibited T cell contact- and MPT-induced production of IL-1beta but not of its natural inhibitor, the secreted form of IL-1 receptor antagonist (sIL-1Ra). METHODOLOGY/PRINCIPAL FINDINGS: Labeled MPT were used to assess their interaction with monocytes and T lymphocytes by flow cytometry. Similarly, interactions of labeled HDL with monocytes and MPT were assessed by flow cytometry. In parallel, the MPT-induction of IL-1beta and sIL-1Ra production in human monocytes and the effect of HDL were assessed in cell cultures. The results show that MPT, but not MP generated by activated endothelial cells, bond monocytes to trigger cytokine production. MPT did not bind T cells. The inhibition of IL-1beta production by HDL correlated with the inhibition of MPT binding to monocytes. HDL interacted with MPT rather than with monocytes suggesting that they bound the activating factor(s) of T cell surface. Furthermore, prototypical pro-inflammatory cytokines and chemokines such as TNF, IL-6, IL-8, CCL3 and CCL4 displayed a pattern of production induced by MPT and inhibition by HDL similar to IL-1beta, whereas the production of CCL2, like that of sIL-1Ra, was not inhibited by HDL. CONCLUSIONS/SIGNIFICANCE: HDL inhibit both MPT binding to monocytes and the MPT-induced production of some but not all cytokines, shedding new light on the mechanism by which HDL display their anti-inflammatory functions

    Experimental mapping of soluble protein domains using a hierarchical approach

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    Exploring the function and 3D space of large multidomain protein targets often requires sophisticated experimentation to obtain the targets in a form suitable for structure determination. Screening methods capable of selecting well-expressed, soluble fragments from DNA libraries exist, but require the use of automation to maximize chances of picking a few good candidates. Here, we describe the use of an insertion dihydrofolate reductase (DHFR) vector to select in-frame fragments and a split-GFP assay technology to filter-out constructs that express insoluble protein fragments. With the incorporation of an IPCR step to create high density, focused sublibraries of fragments, this cost-effective method can be performed manually with no a priori knowledge of domain boundaries while permitting single amino acid resolution boundary mapping. We used it on the well-characterized p85α subunit of the phosphoinositide-3-kinase to demonstrate the robustness and efficiency of our methodology. We then successfully tested it onto the polyketide synthase PpsC from Mycobacterium tuberculosis, a potential drug target involved in the biosynthesis of complex lipids in the cell envelope. X-ray quality crystals from the acyl-transferase (AT), dehydratase (DH) and enoyl-reductase (ER) domains have been obtained

    An overview of the cutaneous porphyrias

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    This is an overview of the cutaneous porphyrias. It is a narrative review based on the published literature and my personal experience; it is not based on a formal systematic search of the literature. The cutaneous porphyrias are a diverse group of conditions due to inherited or acquired enzyme defects in the porphyrin–haem biosynthetic pathway. All the cutaneous porphyrias can have (either as a consequence of the porphyria or as part of the cause of the porphyria) involvement of other organs as well as the skin. The single commonest cutaneous porphyria in most parts of the world is acquired porphyria cutanea tarda, which is usually due to chronic liver disease and liver iron overload. The next most common cutaneous porphyria, erythropoietic protoporphyria, is an inherited disorder in which the accumulation of bile-excreted protoporphyrin can cause gallstones and, rarely, liver disease. Some of the porphyrias that cause blistering (usually bullae) and fragility (clinically and histologically identical to porphyria cutanea tarda) can also be associated with acute neurovisceral porphyria attacks, particularly variegate porphyria and hereditary coproporphyria. Management of porphyria cutanea tarda mainly consists of visible-light photoprotection measures while awaiting the effects of treating the underlying liver disease (if possible) and treatments to reduce serum iron and porphyrin levels. In erythropoietic protoporphyria, the underlying cause can be resolved only with a bone marrow transplant (which is rarely justifiable in this condition), so management consists particularly of visible-light photoprotection and, in some countries, narrowband ultraviolet B phototherapy. Afamelanotide is a promising and newly available treatment for erythropoietic protoporphyria and has been approved in Europe since 2014

    Combinations of Host Biomarkers Predict Mortality among Ugandan Children with Severe Malaria: A Retrospective Case-Control Study

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    Background: Severe malaria is a leading cause of childhood mortality in Africa. However, at presentation, it is difficult to predict which children with severe malaria are at greatest risk of death. Dysregulated host inflammatory responses and endothelial activation play central roles in severe malaria pathogenesis. We hypothesized that biomarkers of these processes would accurately predict outcome among children with severe malaria. Methodology/Findings: Plasma was obtained from children with uncomplicated malaria (n = 53), cerebral malaria (n = 44) and severe malarial anemia (n = 59) at time of presentation to hospital in Kampala, Uganda. Levels of angiopoietin-2, von Willebrand Factor (vWF), vWF propeptide, soluble P-selectin, soluble intercellular adhesion molecule-1 (ICAM-1), soluble endoglin, soluble FMS-like tyrosine kinase-1 (Flt-1), soluble Tie-2, C-reactive protein, procalcitonin, 10 kDa interferon gamma-induced protein (IP-10), and soluble triggering receptor expressed on myeloid cells-1 (TREM-1) were determined by ELISA. Receiver operating characteristic (ROC) curve analysis was used to assess predictive accuracy of individual biomarkers. Six biomarkers (angiopoietin-2, soluble ICAM-1, soluble Flt-1, procalcitonin, IP-10, soluble TREM-1) discriminated well between children who survived severe malaria infection and those who subsequently died (area under ROC curve>0.7). Combinational approaches were applied in an attempt to improve accuracy. A biomarker score was developed based on dichotomization and summation of the six biomarkers, resulting in 95.7% (95% CI: 78.1-99.9) sensitivity and 88.8% (79.7-94.7) specificity for predicting death. Similar predictive accuracy was achieved with models comprised of 3 biomarkers. Classification tree analysis generated a 3-marker model with 100% sensitivity and 92.5% specificity (cross-validated misclassification rate: 15.4%, standard error 4.9%). Conclusions: We identified novel host biomarkers of pediatric severe and fatal malaria (soluble TREM-1 and soluble Flt-1) and generated simple biomarker combinations that accurately predicted death in an African pediatric population. While requiring validation in further studies, these results suggest the utility of combinatorial biomarker strategies as prognostic tests for severe malaria
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