4,372 research outputs found
Contributions of MyD88-dependent receptors and CD11c-positive cells to corneal epithelial barrier function against Pseudomonas aeruginosa.
Previously we reported that corneal epithelial barrier function against Pseudomonas aeruginosa was MyD88-dependent. Here, we explored contributions of MyD88-dependent receptors using vital mouse eyes and confocal imaging. Uninjured IL-1R (-/-) or TLR4 (-/-) corneas, but not TLR2 (-/-), TLR5 (-/-), TLR7 (-/-), or TLR9 (-/-), were more susceptible to P. aeruginosa adhesion than wild-type (3.8-fold, 3.6-fold respectively). Bacteria adherent to the corneas of IL-1R (-/-) or TLR5 (-/-) mice penetrated beyond the epithelial surface only if the cornea was superficially-injured. Bone marrow chimeras showed that bone marrow-derived cells contributed to IL-1R-dependent barrier function. In vivo, but not ex vivo, stromal CD11c+ cells responded to bacterial challenge even when corneas were uninjured. These cells extended processes toward the epithelial surface, and co-localized with adherent bacteria in superficially-injured corneas. While CD11c+ cell depletion reduced IL-6, IL-1β, CXCL1, CXCL2 and CXCL10 transcriptional responses to bacteria, and increased susceptibility to bacterial adhesion (>3-fold), the epithelium remained resistant to bacterial penetration. IL-1R (-/-) corneas also showed down-regulation of IL-6 and CXCL1 genes with and without bacterial challenge. These data show complex roles for TLR4, TLR5, IL-1R and CD11c+ cells in constitutive epithelial barrier function against P. aeruginosa, with details dependent upon in vivo conditions
Exploring Faculty and Staff PA Barriers at a Large University
Introduction: Physical inactivity is a leading cause of morbidity and mortality. Worksites provide an ideal environment for physical activity (PA) interventions. The aim was to use the Nominal Group Technique (NGT) to examine university employees’ perceptions of worksite PA barriers and benefits. Methods: A focus group using the NGT and the Health Belief Model was conducted to assess employees’ perceived susceptibility of physical inactivity, perceptions of barriers and benefits to PA, and cues to action. Results: Findings showed university employees experienced similar barriers to PA as employees in other sectors, including lack of time and knowledge. Participants reported unique benefits to being physical active, notably being physically active allowed them to maintain demanding professional and personal lifestyles. Discussion: Results imply university employees experienced benefits to PA consistent with other worksite populations; the surprising benefits of PA for this population are strong motivators and would provide an excellent basis for interventions. Results also indicate although university employees face similar barriers to PA as other worksites, the unique barriers for this worksite should be the focus for worksite programs for this population. Similarly to the benefits, the unique barriers of this population should influence development of interventions to promote PA on campuses
Synthesis of the 4-aza cyclopentenone analogue of Δ12,14-15-deoxy-PGJ2 and S-cysteine adducts
Abstract The synthesis of a series of 4-aza cross-conjugated cyclopentenones, inspired by the natural prostaglandin Δ12,14-15-deoxy-PGJ2 (5) is described. Using the 4-aza cyclopentenone 7, the installation of the α-side chain was performed using N-functionalisation, following a Boc-deprotection. The ω-side chain was then installed through a Baylis-Hillman type aldol reaction with trans-2-octenal. This afforded 11, the aza-analogue of 5. With this prostaglandin analogue in hand, a series of thiol adducts (14–16) were prepared. Included are activities for compounds 11 and 14–16 in relation to inhibition of the transcription factor NF-κB
Socioeconomic inequalities in children’s diet: the role of the home food environment
Abstract Background It is well documented in the literature that low socioeconomic status (SES) is associated with lower consumption of healthy foods and that these differences in consumption patterns are influenced by neighborhood food environments. Less understood is the role that SES differences in physical and social aspects of the home food environment play in consumption patterns. Methods Using data on 4th grade children from the 2009–2011 Texas School Physical Activity and Nutrition (SPAN) study, we used mixed-effects regression models to test the magnitude of differences in the SPAN Health Eating Index (SHEI) by parental education as an indicator of SES, and the extent to which adjusting for measures of the home food environment, and measures of the neighborhood environment accounted for these SES differences. Results Small but significant differences in children’s SHEI by SES strata exist (-1.33 between highest and lowest SES categories, p<0.01). However, incorporating home food environment and neighborhood environment measures in this model eliminates these differences (-0.7, p=0.145). Home food environment explains a greater portion of the difference. Both social (mealtime structure) and physical aspects (food availability) of the home food environment are strongly associated with consumption of healthy and unhealthy foods. Conclusions Our findings suggest that modifiable parent behaviors at home can improve children’s eating habits and that the neighborhood may impact diet in ways other than through access to healthy food
Spatially Resolved Chandra HETG Spectroscopy of the NLR Ionization Cone in NGC 1068
We present initial results from a new 440-ks Chandra HETG GTO observation of
the canonical Seyfert 2 galaxy NGC 1068. The proximity of NGC 1068, together
with Chandra's superb spatial and spectral resolution, allow an unprecedented
view of its nucleus and circumnuclear NLR. We perform the first spatially
resolved high-resolution X-ray spectroscopy of the `ionization cone' in any
AGN, and use the sensitive line diagnostics offered by the HETG to measure the
ionization state, density, and temperature at discrete points along the ionized
NLR. We argue that the NLR takes the form of outflowing photoionized gas,
rather than gas that has been collisionally ionized by the small-scale radio
jet in NGC 1068. We investigate evidence for any velocity gradients in the
outflow, and describe our next steps in modeling the spatially resolved spectra
as a function of distance from the nucleus.Comment: 5 pages, 2 figures, 1 video. To appear in refereed Proceedings of
"X-ray Astronomy 2009: Present Status, Multi-Wavelength Approach and Future
Perspectives", Bologna, Italy, September 7-11, 2009, AIP, eds. A. Comastri,
M. Cappi, and L. Angelin
Stress-Induced Transformations of Polarization Switching in CuInPS Nanoparticles
Using the Landau-Ginzburg-Devonshire approach, we study stress-induced
transformations of polarization switching in ferrielectric CuInP2S6
nanoparticles for three different shapes: a disk, a sphere, and a needle.
Semiconducting properties of a nanoparticle are modeled by a surface charge
layer, whose effective screening length can be rather small due to the
field-effect. We reveal a very strong and unusual influence of hydrostatic
pressure on the appearance of polarization switching in CuInP2S6 nanoparticles,
hysteresis loops shape, magnitude of the remanent polarization, and coercive
fields, and explain the effects by the anomalous temperature dependence and
"inverted" signs of CuInP2S6 linear and nonlinear electrostriction coupling
coefficients. In particular, by varying the sign of the applied pressure (from
tension to compression) and its magnitude (from zero to several hundreds of
MPa), quasi-static hysteresis-less paraelectric curves can transform into
double, triple, pinched, or single hysteresis loops. Due to the sufficiently
wide temperature and pressure ranges of double, triple, and pinched hysteresis
loop stability (at least in comparison with many other ferroelectrics),
CuInP2S6 nanodisks can be of particular interest for applications in energy
storage (in the region of double loops), CuInP2S6 nanospheres maybe suitable
for dynamic random access multibit memory, and CuInP2S6 nanoneedles are
promising for non-volatile multibit memory cells (in the regions of triple and
pinched loops). The stress control of the polarization switching scenario
allows the creation of advanced piezo-sensors based on CuInP2S6 nanocomposites.Comment: 43 pages, 8 figures, including Supplementary Material with 12 figure
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