1,641 research outputs found

    Liver fluke in Irish sheep: prevalence and associations with management practices and co-infection with rumen fluke

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    peer-reviewedBackground: The present study aimed to identify the national prevalence of Fasciola hepatica in Irish sheep and to conduct a risk analysis assessment based on management and treatment practices in participating focks. Also, co-infection with rumen fuke was quantifed and its association with liver fuke and management practices was assessed. Methods: A total of 305 sheep focks were selected ensuring even national representation of the sheep population. Participating farms were asked to complete a survey questionnaire on farm management practices and submit faecal samples during the winter of 2014–2015. Pooled faecal samples were analysed for the presence of F. hepatica and coinfection with rumen fuke. Apparent and true prevalence were calculated, additionally, the rate of co-infection with rumen fuke was also obtained. Correlation and regression analyses were used for assessing associations between management practices, liver fuke infection and co-infection with rumen fuke. Results: The national true prevalence of F. hepatica was 50.4% (n=305). Regional prevalence varied from 41% in the east to 52% in the south. Co-infection with rumen fuke was observed in 40% of the studied population and corre‑ lated with increased F. hepatica egg counts (OR=2.9; P≤0.001). Predominant breeds were Sufolk, Texel and Horned Mountain breeds. Beef cattle were the most frequent type of other livestock present on farms and mixed species grazing was frequently reported (73%). More than half of the focks reported a mid-to-late lambing period (MarchApril). Use of mountain land for grazing was of 32%. Flukicides were most commonly used twice over the autumnwinter period. Regression analyses highlighted signifcant association of F. hepatica status, with the presence of other livestock on farm, frequency of fukicides used during the winter and clinical presentation of liver fuke. A signifcant increase in eggs per gram of faeces was observed in Charollais sheep in comparison with all other breeds. Co-infec‑ tion with F. hepatica and Calicophoron daubneyi was also signifcantly associated with the presence of other livestock on the farm, type of fukicide used and clinical fasciolosis. Conclusions: The present study provides up-to-date information on the prevalence of F. hepatica in Irish sheep and adds insight to the epidemiology of the disease. These fndings will be useful for designing new holistic control meas‑ ures for F. hepatica infection

    Are Small GTPases Signal Hubs in Sugar-Mediated Induction of Fructan Biosynthesis?

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    External sugar initiates biosynthesis of the reserve carbohydrate fructan, but the molecular processes mediating this response remain obscure. Previously it was shown that a phosphatase and a general kinase inhibitor hamper fructan accumulation. We use various phosphorylation inhibitors both in barley and in Arabidopsis and show that the expression of fructan biosynthetic genes is dependent on PP2A and different kinases such as Tyr-kinases and PI3-kinases. To further characterize the phosphorylation events involved, comprehensive analysis of kinase activities in the cell was performed using a PepChip, an array of >1000 kinase consensus substrate peptide substrates spotted on a chip. Comparison of kinase activities in sugar-stimulated and mock(sorbitol)-treated Arabidopsis demonstrates the altered phosphorylation of many consensus substrates and documents the differences in plant kinase activity upon sucrose feeding. The different phosphorylation profiles obtained are consistent with sugar-mediated alterations in Tyr phosphorylation, cell cycling, and phosphoinositide signaling, and indicate cytoskeletal rearrangements. The results lead us to infer a central role for small GTPases in sugar signaling

    Toxicidad sub crónica y actividad analgésica in vivo del extracto clorofórmico de las hojas de Calea urticifolia (Juanislama

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    Introduction: The population uses medicinal plants indiscriminately to treat diseases, with the believe that they are safe and lack adverse effects. Objective: To determine the in vivo toxicological and analgesic effect of the chloroform extract of Calea urticifolia leaves. Methodology: The toxicological study was performed using a 90- day sub-chronic toxicity test in NIH mice, at repeated and continuous doses. . Blood biochemistry, hematology and histopathological examination of organs were performed. The analgesic activity was evaluated in vivo using a model of abdominal contortions. Results: The administration of the plant extract caused the appearance of clinical signs of toxicity, alterations in hematic parameters and blood biochemistry, as well as histological alterations in some of organs. The analgesic activity at 100 mg/kg was similar to the Indomethacin drug. Conclusion: Despite the proven analgesic activity, according to the observed toxicological effects in this study, the prolonged use of Calea urticifolia leaves is not recommended for the treatment of diseasesIntroducción: La población utiliza la medicina a base de hierbas de forma indiscriminada basándose en la creencia de que las plantas medicinales carecen de efectos adversos. Objetivo: Determinar in vivo el efecto toxicológico y analgésico del extracto clorofórmico de las hojas de Calea urticifolia. Metodología: El estudio toxicológico fue realizado mediante la prueba de toxicidad subcrónica de 90 días, a dosis repetidas y continuas en ratones NIH. Se realizaron análisis de bioquímica sanguínea, hematología y el examen histopatológico de órganos. La actividad analgésica fue evaluada con el modelo in vivo de contorsiones abdominales. Resultados: La administración del extracto vegetal provocó la aparición de signos clínicos de toxicidad, alteraciones en los parámetros hematólogos y bioquímica sanguínea, además alteraciones histológicas en algunos de los órganos. La actividad analgésica a 100 mg/kg resultó comparable con el fármaco indometacina. Conclusión: Pese a la actividad analgésica demostrada, y de acuerdo a los efectos toxicológicos encontrados, no se recomienda el uso prolongado de las hojas de Calea urticifolia, para el tratamiento de enfermedade

    IL-4Rα-Independent Expression of Mannose Receptor and Ym1 by Macrophages Depends on their IL-10 Responsiveness

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    IL-4Rα-dependent responses are essential for granuloma formation and host survival during acute schistosomiasis. Previously, we demonstrated that mice deficient for macrophage-specific IL-4Rα (LysMcreIl4ra−/lox) developed increased hepatotoxicity and gut inflammation; whereas inflammation was restricted to the liver of mice lacking T cell-specific IL-4Rα expression (iLckcreIl4ra−/lox). In the study presented here we further investigated their role in liver granulomatous inflammation. Frequencies and numbers of macrophage, lymphocyte or granulocyte populations, as well as Th1/Th2 cytokine responses were similar in Schistosoma mansoni-infected LysMcreIl4ra−/lox liver granulomas, when compared to Il4ra−/lox control mice. In contrast, a shift to Th1 responses with high IFN-γ and low IL-4, IL-10 and IL-13 was observed in the severely disrupted granulomas of iLckcreIl4ra−/lox and Il4ra−/− mice. As expected, alternative macrophage activation was reduced in both LysMcreIl4ra−/lox and iLckcreIl4ra−/lox granulomas with low arginase 1 and heightened nitric oxide synthase RNA expression in granuloma macrophages of both mouse strains. Interestingly, a discrete subpopulation of SSChighCD11b+I-A/I-EhighCD204+ macrophages retained expression of mannose receptor (MMR) and Ym1 in LysMcreIl4ra−/lox but not in iLckcreIl4ra−/lox granulomas. While aaMφ were in close proximity to the parasite eggs in Il4ra−/lox control mice, MMR+Ym1+ macrophages in LysMcreIl4ra−/lox mice were restricted to the periphery of the granuloma, indicating that they might have different functions. In vivo IL-10 neutralisation resulted in the disappearance of MMR+Ym1+ macrophages in LysMcreIl4ra−/lox mice. Together, these results show that IL-4Rα-responsive T cells are essential to drive alternative macrophage activation and to control granulomatous inflammation in the liver. The data further suggest that in the absence of macrophage-specific IL-4Rα signalling, IL-10 is able to drive mannose receptor- and Ym1-positive macrophages, associated with control of hepatic granulomatous inflammation

    A search for faint resolved galaxies beyond the Milky Way in DES Year 6: A new faint, diffuse dwarf satellite of NGC 55

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    We report results from a systematic wide-area search for faint dwarf galaxies at heliocentric distances from 0.3 to 2 Mpc using the full six years of data from the Dark Energy Survey (DES). Unlike previous searches over the DES data, this search specifically targeted a field population of faint galaxies located beyond the Milky Way virial radius. We derive our detection efficiency for faint, resolved dwarf galaxies in the Local Volume with a set of synthetic galaxies and expect our search to be complete to MVM_V ~ (7,10)(-7, -10) mag for galaxies at D=(0.3,2.0)D = (0.3, 2.0) Mpc respectively. We find no new field dwarfs in the DES footprint, but we report the discovery of one high-significance candidate dwarf galaxy at a distance of 2.2+0.050.122.2\substack{+0.05\\-0.12} Mpc, a potential satellite of the Local Volume galaxy NGC 55, separated by 4747 arcmin (physical separation as small as 30 kpc). We estimate this dwarf galaxy to have an absolute V-band magnitude of 8.0+0.50.3-8.0\substack{+0.5\\-0.3} mag and an azimuthally averaged physical half-light radius of 2.2+0.50.42.2\substack{+0.5\\-0.4} kpc, making this one of the lowest surface brightness galaxies ever found with μ=32.3\mu = 32.3 mag arcsec2{\rm arcsec}^{-2}. This is the largest, most diffuse galaxy known at this luminosity, suggesting possible tidal interactions with its host.Comment: 20 pages, 7 figure

    Analysis of the P. lividus sea urchin genome highlights contrasting trends of genomic and regulatory evolution in deuterostomes

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    Sea urchins are emblematic models in developmental biology and display several characteristics that set them apart from other deuterostomes. To uncover the genomic cues that may underlie these specificities, we generated a chromosome-scale genome assembly for the sea urchin Paracentrotus lividus and an extensive gene expression and epigenetic profiles of its embryonic development. We found that, unlike vertebrates, sea urchins retained ancestral chromosomal linkages but underwent very fast intrachromosomal gene order mixing. We identified a burst of gene duplication in the echinoid lineage and showed that some of these expanded genes have been recruited in novel structures (water vascular system, Aristotle's lantern, and skeletogenic micromere lineage). Finally, we identified gene-regulatory modules conserved between sea urchins and chordates. Our results suggest that gene-regulatory networks controlling development can be conserved despite extensive gene order rearrangement

    What Was the Set of Ubiquitin and Ubiquitin-Like Conjugating Enzymes in the Eukaryote Common Ancestor?

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    Ubiquitin (Ub)-conjugating enzymes (E2) are key enzymes in ubiquitination or Ub-like modifications of proteins. We searched for all proteins belonging to the E2 enzyme super-family in seven species (Homo sapiens, Mus musculus, Drosophila melanogaster, Caenorhabditis elegans, Schizosaccharomyces pombe, Saccharomyces cerevisiae, and Arabidopsis thaliana) to identify families and to reconstruct each family’s phylogeny. Our phylogenetic analysis of 207 genes led us to define 17 E2 families, with 37 E2 genes, in the human genome. The subdivision of E2 into four classes did not correspond to the phylogenetic tree. The sequence signature HPN (histidine–proline–asparagine), followed by a tryptophan residue at 16 (up to 29) amino acids, was highly conserved. When present, the active cysteine was found 7 to 8 amino acids from the C-terminal end of HPN. The secondary structures were characterized by a canonical alpha/beta fold. Only family 10 deviated from the common organization because the proteins were devoid of enzymatic activity. Family 7 had an insertion between beta strands 1 and 2; families 3, 5 and 14 had an insertion between the active cysteine and the conserved tryptophan. The three-dimensional data of these proteins highlight a strong structural conservation of the core domain. Our analysis shows that the primitive eukaryote ancestor possessed a diversified set of E2 enzymes, thus emphasizing the importance of the Ub pathway. This comprehensive overview of E2 enzymes emphasizes the diversity and evolution of this superfamily and helps clarify the nomenclature and true orthologies. A better understanding of the functions of these enzymes is necessary to decipher several human diseases

    Validation of plasma proteomic biomarkers relating to brain amyloid burden in the EMIF-Alzheimer's disease multimodal biomarker discovery cohort

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    We have previously investigated, discovered, and replicated plasma protein biomarkers for use to triage potential trials participants for PET or cerebrospinal fluid measures of Alzheimer's disease (AD) pathology. This study sought to undertake validation of these candidate plasma biomarkers in a large, multi-center sample collection. Targeted plasma analyses of 34 proteins with prior evidence for prediction of in vivo pathology were conducted in up to 1,000 samples from cognitively healthy elderly individuals, people with mild cognitive impairment, and in patients with AD-type dementia, selected from the EMIF-AD catalogue. Proteins were measured using Luminex xMAP, ELISA, and Meso Scale Discovery assays. Seven proteins replicated in their ability to predict in vivo amyloid pathology. These proteins form a biomarker panel that, along with age, could significantly discriminate between individuals with high and low amyloid pathology with an area under the curve of 0.74. The performance of this biomarker panel remained consistent when tested in apolipoprotein E ϵ4 non-carrier individuals only. This blood-based panel is biologically relevant, measurable using practical immunocapture arrays, and could significantly reduce the cost incurred to clinical trials through screen failure

    Cell-Free Antigens from Paracoccidioides brasiliensis Drive IL-4 Production and Increase the Severity of Paracoccidioidomycosis

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    The thermally dimorphic fungus Paracoccidioides brasiliensis (Pb) is the causative agent of paracoccidioidomycosis (PCM), one of the most frequent systemic mycosis that affects the rural population in Latin America. PCM is characterized by a chronic inflammatory granulomatous reaction, which is consequence of a Th1-mediated adaptive immune response. In the present study we investigated the mechanisms involved in the immunoregulation triggered after a prior contact with cell-free antigens (CFA) during a murine model of PCM. The results showed that the inoculation of CFA prior to the infection resulted in disorganized granulomatous lesions and increased fungal replication in the lungs, liver and spleen, that paralleled with the higher levels of IL-4 when compared with the control group. The role of IL-4 in facilitating the fungal growth was demonstrated in IL-4-deficient- and neutralizing anti-IL-4 mAb-treated mice. The injection of CFA did not affect the fungal growth in these mice, which, in fact, exhibited a significant diminished amount of fungus in the tissues and smaller granulomas. Considering that in vivo anti-IL-4-application started one week after the CFA-inoculum, it implicates that IL-4-CFA-induced is responsible by the mediation of the observed unresponsiveness. Further, the characterization of CFA indicated that a proteic fraction is required for triggering the immunosuppressive mechanisms, while glycosylation or glycosphingolipids moieties are not. Taken together, our data suggest that the prior contact with soluble Pb antigens leads to severe PCM in an IL-4 dependent manner

    Bioenergetic status modulates motor neuron vulnerability and pathogenesis in a zebrafish model of spinal muscular atrophy

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    Degeneration and loss of lower motor neurons is the major pathological hallmark of spinal muscular atrophy (SMA), resulting from low levels of ubiquitously-expressed survival motor neuron (SMN) protein. One remarkable, yet unresolved, feature of SMA is that not all motor neurons are equally affected, with some populations displaying a robust resistance to the disease. Here, we demonstrate that selective vulnerability of distinct motor neuron pools arises from fundamental modifications to their basal molecular profiles. Comparative gene expression profiling of motor neurons innervating the extensor digitorum longus (disease-resistant), gastrocnemius (intermediate vulnerability), and tibialis anterior (vulnerable) muscles in mice revealed that disease susceptibility correlates strongly with a modified bioenergetic profile. Targeting of identified bioenergetic pathways by enhancing mitochondrial biogenesis rescued motor axon defects in SMA zebrafish. Moreover, targeting of a single bioenergetic protein, phosphoglycerate kinase 1 (Pgk1), was found to modulate motor neuron vulnerability in vivo. Knockdown of pgk1 alone was sufficient to partially mimic the SMA phenotype in wild-type zebrafish. Conversely, Pgk1 overexpression, or treatment with terazosin (an FDA-approved small molecule that binds and activates Pgk1), rescued motor axon phenotypes in SMA zebrafish. We conclude that global bioenergetics pathways can be therapeutically manipulated to ameliorate SMA motor neuron phenotypes in vivo
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