130 research outputs found

    Variability in ice motion and dynamic discharge from Devon Ice Cap, Nunavut, Canada

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    © The Author(s) 2017. Feature tracking of approximately annually separated Landsat-7 ETM+ imagery acquired from 1999 to 2010 and speckle tracking of 24-day separated RADARSAT-2 imagery acquired from 2009 to 2015 reveal that motion of the major tidewater glaciers of Devon Ice Cap is more variable than previously described. The flow of almost half (six of 14) of the outlet glaciers slowed over the observation period, while that of the terminus regions of three of 14 of the glaciers sped up in the most recent years of observation. The North Croker Bay Glacier of southern Devon Ice Cap showed the greatest variability in motion, oscillating between multi-year (three or more) periods of slower and faster flow and exhibited a pattern of velocity variability that is different from that of the rest of the ice cap's outlet glaciers. Comparisons between areas of dynamic variability and glacier bed topography indicate that velocity variability is largely restricted to regions where the glacier bed is grounded below sea level. Derived velocities are combined with measurements of ice thickness at the fronts of tidewater glacier to determine a mean annual (2009; 2011-15) dynamic ice discharge of 0.41 ± 0.11 Gt a-1 for Devon Ice Cap. The Belcher Glacier is becoming a larger source of mass loss via ice discharge.NERC (NE/K004999/1

    Autoimmune and autoinflammatory mechanisms in uveitis

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    The eye, as currently viewed, is neither immunologically ignorant nor sequestered from the systemic environment. The eye utilises distinct immunoregulatory mechanisms to preserve tissue and cellular function in the face of immune-mediated insult; clinically, inflammation following such an insult is termed uveitis. The intra-ocular inflammation in uveitis may be clinically obvious as a result of infection (e.g. toxoplasma, herpes), but in the main infection, if any, remains covert. We now recognise that healthy tissues including the retina have regulatory mechanisms imparted by control of myeloid cells through receptors (e.g. CD200R) and soluble inhibitory factors (e.g. alpha-MSH), regulation of the blood retinal barrier, and active immune surveillance. Once homoeostasis has been disrupted and inflammation ensues, the mechanisms to regulate inflammation, including T cell apoptosis, generation of Treg cells, and myeloid cell suppression in situ, are less successful. Why inflammation becomes persistent remains unknown, but extrapolating from animal models, possibilities include differential trafficking of T cells from the retina, residency of CD8(+) T cells, and alterations of myeloid cell phenotype and function. Translating lessons learned from animal models to humans has been helped by system biology approaches and informatics, which suggest that diseased animals and people share similar changes in T cell phenotypes and monocyte function to date. Together the data infer a possible cryptic infectious drive in uveitis that unlocks and drives persistent autoimmune responses, or promotes further innate immune responses. Thus there may be many mechanisms in common with those observed in autoinflammatory disorders

    C-Terminal Domain Deletion Enhances the Protective Activity of cpa/cpb Loaded Solid Lipid Nanoparticles against Leishmania major in BALB/c Mice

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    Cutaneous leishmaniasis (CL) is the most common form of leishmaniasis with an annual incidence of approximately 2 million cases and is endemic in 88 countries, including Iran. CL's continued spread, along with rather ineffectual treatments and drug-resistant variants emergence has increased the need for advanced preventive strategies. We studied Type II cysteine proteinase (CPA) and Type I (CPB) with its C-terminal extension (CTE) as cocktail DNA vaccine against murine and canine leishmaniasis. However, adjuvants' success in enhancing immune responses to selected antigens led us to refocus our vaccine development programs. Herein, we discuss cationic solid lipid nanoparticles' (cSLN) ability to improve vaccine-induced protective efficacy against CL and subsequent lesion size and parasite load reduction in BALB/c mice. For this work, we evaluated five different conventional as well as novel parasite detection techniques, i.e., footpad imaging, footpad flowcytometry and lymph node flowcytometry for disease progression assessments. Vaccination with cSLN-cpa/cpb-CTE formulation showed highest parasite inhibition at 3-month post vaccination. Immunized mice showed reduced IL-5 level and significant IFN-ã increase, compared to control groups. We think our study represents a potential future and a major step forward in vaccine development against leishmaniasis

    Early biomarkers and potential mediators of ventilation-induced lung injury in very preterm lambs

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    BACKGROUND: Bronchopulmonary dysplasia (BPD) is closely associated with ventilator-induced lung injury (VILI) in very preterm infants. The greatest risk of VILI may be in the immediate period after birth, when the lungs are surfactant deficient, still partially filled with liquid and not uniformly aerated. However, there have been very few studies that have examined this immediate post-birth period and identified the initial injury-related pathways that are activated. We aimed to determine if the early response genes; connective tissue growth factor (CTGF), cysteine rich-61 (CYR61) and early growth response 1 (EGR1), were rapidly induced by VILI in preterm lambs and whether ventilation with different tidal volumes caused different inflammatory cytokine and early response gene expression. METHODS: To identify early markers of VILI, preterm lambs (132 d gestational age; GA, term approximately 147 d) were resuscitated with an injurious ventilation strategy (V(T) 20 mL/kg for 15 min) then gently ventilated (5 mL/kg) for 15, 30, 60 or 120 min (n = 4 in each). To determine if early response genes and inflammatory cytokines were differentially regulated by different ventilation strategies, separate groups of preterm lambs (125 d GA; n = 5 in each) were ventilated from birth with a V(T) of 5 (VG5) or 10 mL/kg (VG10) for 135 minutes. Lung gene expression levels were compared to levels prior to ventilation in age-matched control fetuses. RESULTS: CTGF, CYR61 and EGR1 lung mRNA levels were increased approximately 25, 50 and 120-fold respectively (p < 0.05), within 30 minutes of injurious ventilation. VG5 and VG10 caused significant increases in CTGF, CYR61, EGR1, IL1- , IL-6 and IL-8 mRNA levels compared to control levels. CTGF, CYR61, IL-6 and IL-8 expression levels were higher in VG10 than VG5 lambs; although only the IL-6 and CYR61 mRNA levels reached significance. CONCLUSION: CTGF, CYR61 and EGR1 may be novel early markers of lung injury and mechanical ventilation from birth using relatively low tidal volumes may be less injurious than using higher tidal volumes

    Microarray analysis of expression of cell death-associated genes in rat spinal cord cells exposed to cyclic tensile stresses in vitro

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    <p>Abstract</p> <p>Background</p> <p>The application of mechanical insults to the spinal cord results in profound cellular and molecular changes, including the induction of neuronal cell death and altered gene expression profiles. Previous studies have described alterations in gene expression following spinal cord injury, but the specificity of this response to mechanical stimuli is difficult to investigate in vivo. Therefore, we have investigated the effect of cyclic tensile stresses on cultured spinal cord cells from E15 Sprague-Dawley rats, using the FX3000<sup>® </sup>Flexercell Strain Unit. We examined cell morphology and viability over a 72 hour time course. Microarray analysis of gene expression was performed using the Affymetrix GeneChip System<sup>®</sup>, where categorization of identified genes was performed using the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) systems. Changes in expression of 12 genes were validated with quantitative real-time reverse transcription polymerase chain reaction (RT-PCR).</p> <p>Results</p> <p>The application of cyclic tensile stress reduced the viability of cultured spinal cord cells significantly in a dose- and time-dependent manner. Increasing either the strain or the strain rate independently was associated with significant decreases in spinal cord cell survival. There was no clear evidence of additive effects of strain level with strain rate. GO analysis identified 44 candidate genes which were significantly related to "apoptosis" and 17 genes related to "response to stimulus". KEGG analysis identified changes in the expression levels of 12 genes of the mitogen-activated protein kinase (MAPK) signaling pathway, which were confirmed to be upregulated by RT-PCR analysis.</p> <p>Conclusions</p> <p>We have demonstrated that spinal cord cells undergo cell death in response to cyclic tensile stresses, which were dose- and time-dependent. In addition, we have identified the up regulation of various genes, in particular of the MAPK pathway, which may be involved in this cellular response. These data may prove useful, as the accurate knowledge of neuronal gene expression in response to cyclic tensile stress will help in the development of molecular-based therapies for spinal cord injury.</p

    Процесс анализа угроз, влияющих на экономическую устойчивость предприятия

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    На основании проведенного исследования были выявлены факторы возникновения угроз, их группировка по степени воздействию на экономическую устойчивость предприятий и рассмотрена формализация процесса анализа угроз экономической устойчивости предприятий. В условиях рыночной экономики невозможно управлять предприятием без учета влияния угроз, а для эффективного управления важно не только знать об их присутствии, а и правильно идентифицировать конкретную угрозу.На підставі проведеного дослідження були виявлені чинники виникнення загроз, їх угруповання по степені впливу на економічну стійкість підприємств і розглянута формалізація процесу аналізу загроз економічної стійкості підприємств. В умовах ринкової економіки неможливо керувати підприємством без вивчення впливу загроз, а для ефективного керування важливо не тільки знати про їх присутність, а і правильно ідентифікувати конкретну загрозу.On the basis of the conducted research the factors of origin of threats were exposed, their gourmet on a degree to influence on economic stability of enterprises and formalization of process of analysis of threats of economic stability of enterprises is considered. In the conditions of market economy it is impossible to manage an enterprise without taking into account influencing of threats, and for the effective management it is important not only to know about their presence, and to identify the concrete threat correctly

    Angiopoietin-1 Treatment Reduces Inflammation but Does Not Prevent Ventilator-Induced Lung Injury

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    Background: Loss of integrity of the epithelial and endothelial barriers is thought to be a prominent feature of ventilator-induced lung injury (VILI). Based on its function in vascular integrity, we hypothesize that the angiopoietin (Ang)-Tie2 system plays a role in the development of VILI. The present study was designed to examine the effects of mechanical ventilation on the Ang-Tie2 system in lung tissue. Moreover, we evaluated whether treatment with Ang-1, a Tie2 receptor agonist, protects against inflammation, vascular leakage and impaired gas exchange induced by mechanical ventilation. Methods: Mice were anesthetized, tracheotomized and mechanically ventilated for 5 hours with either an inspiratory pressure of 10 cmH(2)O ('low' tidal volume similar to 7.5 ml/kg; LVT) or 18 cmH(2)O ('high' tidal volume similar to 15 ml/kg; HVT). At initiation of HVT-ventilation, recombinant human Ang-1 was intravenously administered (1 or 4 mu g per animal). Non-ventilated mice served as controls. Results: HVT-ventilation influenced the Ang-Tie2 system in lungs of healthy mice since Ang-1, Ang-2 and Tie2 mRNA were decreased. Treatment with Ang-1 increased Akt-phosphorylation indicating Tie2 signaling. Ang-1 treatment reduced infiltration of granulocytes and expression of keratinocyte-derived chemokine (KC), macrophage inflammatory protein (MIP)-2, monocyte chemotactic protein (MCP)-1 and interleukin (IL)-1 beta caused by HVT-ventilation. Importantly, Ang-1 treatment did not prevent vascular leakage and impaired gas exchange in HVT-ventilated mice despite inhibition of inflammation, vascular endothelial growth factor (VEGF) and Ang-2 expression. Conclusions: Ang-1 treatment downregulates pulmonary inflammation, VEGF and Ang-2 expression but does not protect against vascular leakage and impaired gas exchange induced by HVT-ventilatio

    Dual targeting of p53 and c-MYC selectively eliminates leukaemic stem cells

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    e Glasgow and Manchester Experimental Cancer Medicine Centres (ECMC), which are funded by CR-UK and the Chief Scientist’s Office (Scotland). We acknowledge the funders who have contributed to this work: MRC stratified medicine infrastructure award (A.D.W.), CR-UK C11074/A11008 (F.P., L.E.M.H., T.L.H., A.D.W.); LLR08071 (S.A.A., E.C.); LLR11017 (M.C.); SCD/04 (M.C.); LLR13035 (S.A.A., K.D., A.D.W., and A.P.); LLR14005 (M.T.S., D.V.); KKL690 (L.E.P.); KKL698 (P.B.); LLR08004 (A.D.W., A.P. and A.J.W.); MRC CiC (M.E.D.); The Howat Foundation (FACS support); Friends of Paul O’Gorman (K.D. and FACS support); ELF 67954 (S.A.A.); BSH start up fund (S.A.A.); MR/K014854/1 (K.D.)
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