195 research outputs found

    Female student veterans\u27 resiliency in their role transitions

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    This study examined female student veterans as they pertain to Schlossberg\u27s Theory of Transition (1981), which asserts that many life events influence one’s ability to adapt when transitioning from one role to another in a linear fashion. The results of this study reveal that the participants viewed change not as a transition, but that they faced conflict from competing roles and stressors. Their attainment of their goals resulted from their ability to be resilient

    Centrality measures for graphons: Accounting for uncertainty in networks

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    As relational datasets modeled as graphs keep increasing in size and their data-acquisition is permeated by uncertainty, graph-based analysis techniques can become computationally and conceptually challenging. In particular, node centrality measures rely on the assumption that the graph is perfectly known -- a premise not necessarily fulfilled for large, uncertain networks. Accordingly, centrality measures may fail to faithfully extract the importance of nodes in the presence of uncertainty. To mitigate these problems, we suggest a statistical approach based on graphon theory: we introduce formal definitions of centrality measures for graphons and establish their connections to classical graph centrality measures. A key advantage of this approach is that centrality measures defined at the modeling level of graphons are inherently robust to stochastic variations of specific graph realizations. Using the theory of linear integral operators, we define degree, eigenvector, Katz and PageRank centrality functions for graphons and establish concentration inequalities demonstrating that graphon centrality functions arise naturally as limits of their counterparts defined on sequences of graphs of increasing size. The same concentration inequalities also provide high-probability bounds between the graphon centrality functions and the centrality measures on any sampled graph, thereby establishing a measure of uncertainty of the measured centrality score. The same concentration inequalities also provide high-probability bounds between the graphon centrality functions and the centrality measures on any sampled graph, thereby establishing a measure of uncertainty of the measured centrality score.Comment: Authors ordered alphabetically, all authors contributed equally. 21 pages, 7 figure

    Regulation of Muscle Satellite Cell Activation and Chemotaxis by Angiotensin II

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    The role of angiotensin II (Ang II) in skeletal muscle is poorly understood. We report that pharmacological inhibition of Ang II signaling or ablation of the AT1a receptor significantly impaired skeletal muscle growth following myotrauma, in vivo, likely due to impaired satellite cell activation and chemotaxis. In vitro experiments demonstrated that Ang II treatment activated quiescent myoblasts as evidenced by the upregulation of myogenic regulatory factors, increased number of β-gal+, Myf5-LacZ myoblasts and the acquisition of cellular motility. Furthermore, exogenous treatment with Ang II significantly increased the chemotactic capacity of C2C12 and primary cells while AT1a−/− myoblasts demonstrated a severe impairment in basal migration and were not responsive to Ang II treatment. Additionally, Ang II interacted with myoblasts in a paracrine-mediated fashion as 4 h of cyclic mechanical stimulation resulted in Ang II-induced migration of cocultured myoblasts. Ang II-induced chemotaxis appeared to be regulated by multiple mechanisms including reorganization of the actin cytoskeleton and augmentation of MMP2 activity. Collectively, these results highlight a novel role for Ang II and ACE inhibitors in the regulation of skeletal muscle growth and satellite cell function

    IL-6 Induced STAT3 Signalling Is Associated with the Proliferation of Human Muscle Satellite Cells Following Acute Muscle Damage

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    Although the satellite cell (SC) is a key regulator of muscle growth during development and muscle adaptation following exercise, the regulation of human muscle SC function remains largely unexplored. STAT3 signalling mediated via interleukin-6 (IL-6) has recently come to the forefront as a potential regulator of SC proliferation. The early response of the SC population in human muscle to muscle-lengthening contractions (MLC) as mediated by STAT3 has not been studied.Twelve male subjects (21±2 y; 83±12 kg) performed 300 maximal MLC of the quadriceps femoris at 180°•s(-1) over a 55° range of motion with muscle samples (vastus lateralis) and blood samples (antecubital vein) taken prior to exercise (PRE), 1 hour (T1), 3 hours (T3) and 24 hours (T24) post-exercise. Cytoplasmic and nuclear fractions of muscle biopsies were purified and analyzed for total and phosphorylated STAT3 (p-STAT3) by western blot. p-STAT3 was detected in cytoplasmic fractions across the time course peaking at T24 (p<0.01 vs. PRE). Nuclear total and p-STAT3 were not detected at appreciable levels. However, immunohistochemical analysis revealed a progressive increase in the proportion of SCs expressing p-STAT3 with ∼60% of all SCs positive for p-STAT3 at T24 (p<0.001 vs. PRE). Additionally, cMyc, a STAT3 downstream gene, was significantly up-regulated in SCs at T24 versus PRE (p<0.05). Whole muscle mRNA analysis revealed induction of the STAT3 target genes IL-6, SOCS3, cMyc (peaking at T3, p<0.05), IL-6Rα and GP130 (peaking at T24, p<0.05). In addition, Myf5 mRNA was up-regulated at T24 (p<0.05) with no appreciable change in MRF4 mRNA.We demonstrate that IL-6 induction of STAT3 signaling occurred exclusively in the nuclei of SCs in response to MLC. An increase in the number of cMyc+ SCs indicated that human SCs were induced to proliferate under the control of STAT3 signaling

    Safety and Observations in a Pilot Study of Lenalidomide for Treatment in Autism

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    Autism affects 1 : 88 children in the United States. Familial history of autoimmune disease, autoantibodies in the serum of mothers when there is more than one autistic offspring, and neuroglial response in CSF and brain tissue in autistic patients suggest an immunological variable may be associated with this condition. Lenalidomide has the potential to invoke changes in TNF-α with less toxicity than thalidomide. This pilot study evaluated lenalidomide at reduction of TNF-α and improvement of behavior and language in children with autism with elevated TNF-α. Subjects with elevated TNF-α were given 2.5 mgs lenalidomide daily for 12-weeks. Pharmacodynamics and safety was evaluated. Changes in language and autistic behaviors after six and twelve weeks were measured. Although statistical significance was not achieved for most measures, there were trends toward improvement. After 6-weeks, mean receptive language increased: 60.67 ± 12.06 to 65.00 ± 15.10 (P = 0.11) and symptoms of autism decreased (40.75 ± 5.96 versus 38.67 ± 7.90, P = 0.068). After 12-weeks, CSF-TNF-α declined 57%± 25% from 80.5 ± 41.03 to 38.0 ± 31.27 (P = 0.068). Serum TNF-α declined 57% (92.50 ± 68.92 to 40.25 ± 44.53 (P = 0.048). This study suggests that lenalidomide is tolerated as a treatment by children with autism and should be further studied as a potential agent for cytockine inflammation

    Dissecting Clot Retraction and Platelet Aggregation: CLOT RETRACTION DOES NOT REQUIRE AN INTACT FIBRINOGEN CHAIN C TERMINUS

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    Fibrinogen mediates the processes of platelet aggregation and clot retraction. Previous studies have demonstrated that fibrinogen binding to the platelet receptor alphaIIbbeta3 requires the C-terminal residues of the fibrinogen gamma chain. We made a recombinant human fibrinogen that lacks the gamma chain C-terminal four residues (AGDV). As expected this fibrinogen did not support platelet aggregation. Unexpectedly, this variant did support clot retraction that was indistinguishable from retraction with normal recombinant or plasma fibrinogen. These results suggest that the site on fibrinogen that is required for platelet aggregation differs from the site on fibrin that is required for clot retraction

    University City Sustainability Plan, Fall 2020 & Spring 2021

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    University City Sustainability Plan, Sustainability Exchange, Washington University in St. Louis, Fall 2020 & Spring 202

    A multi-ingredient nutritional supplement enhances exercise training-related reductions in markers of systemic inflammation in healthy older men

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    We evaluated whether twice daily consumption of a multi-ingredient nutritional supplement (SUPP) would reduce systemic inflammatory markers following 6wk of supplementation alone (Phase 1), and the subsequent addition of 12wk exercise training (Phase 2) in healthy older men, in comparison to a carbohydrate-based control (CON). Tumour necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) concentrations were progressively reduced (P-time<0.05) SUPP group. No change in TNF-α or IL-6 concentrations was observed in the CON group

    The Ultraviolet Imaging Telescope: Instrument and Data Characteristics

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    The Ultraviolet Imaging Telescope (UIT) was flown as part of the Astro observatory on the Space Shuttle Columbia in December 1990 and again on the Space Shuttle Endeavor in March 1995. Ultraviolet (1200-3300 Angstroms) images of a variety of astronomical objects, with a 40 arcmin field of view and a resolution of about 3 arcsec, were recorded on photographic film. The data recorded during the first flight are available to the astronomical community through the National Space Science Data Center (NSSDC); the data recorded during the second flight will soon be available as well. This paper discusses in detail the design, operation, data reduction, and calibration of UIT, providing the user of the data with information for understanding and using the data. It also provides guidelines for analyzing other astronomical imagery made with image intensifiers and photographic film.Comment: 44 pages, LaTeX, AAS preprint style and EPSF macros, accepted by PAS
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