487 research outputs found
Adult Non-Cystic Fibrosis Bronchiectasis Is Characterised by Airway Luminal Th17 Pathway Activation
Copyright © 2015 Chen et al. This is an open
access article distributed under the terms of the
Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any
medium, provided the original author and source are
credited.BACKGROUND:
Non-cystic fibrosis (CF) bronchiectasis is characterised by chronic airway infection and neutrophilic inflammation, which we hypothesised would be associated with Th17 pathway activation.
METHODS:
Th17 pathway cytokines were quantified in bronchoalveolar lavage fluid (BALF), and gene expression of IL-17A, IL-1β, IL-8 and IL-23 determined from endobronchial biopsies (EBx) in 41 stable bronchiectasis subjects and 20 healthy controls. Relationships between IL-17A levels and infection status, important clinical measures and subsequent Pseudomonas aeruginosa infection were determined.
RESULTS:
BALF levels of all Th17 cytokines (median (IQR) pg/mL) were significantly higher in bronchiectasis than control subjects, including IL-17A (1.73 (1.19, 3.23) vs. 0.27 (0.24, 0.35), 95% CI 1.05 to 2.21, p<0.0001) and IL-23 (9.48 (4.79, 15.75) vs. 0.70 (0.43, 1.79), 95% CI 4.68 to 11.21, p<0.0001). However, BALF IL-17A levels were not associated with clinical measures or airway microbiology, nor predictive of subsequent P. aeruginosa infection. Furthermore, gene expression of IL-17A in bronchiectasis EBx did not differ from control. In contrast, gene expression (relative to medians of controls) in bronchiectasis EBx was significantly higher than control for IL1β (4.12 (1.24, 8.05) vs 1 (0.13, 2.95), 95% CI 0.05 to 4.07, p = 0.04) and IL-8 (3.75 (1.64, 11.27) vs 1 (0.54, 3.89), 95% CI 0.32 to 4.87, p = 0.02) and BALF IL-8 and IL-1α levels showed significant relationships with clinical measures and airway microbiology. P. aeruginosa infection was associated with increased levels of IL-8 while Haemophilus influenzae was associated with increased IL-1α.
CONCLUSIONS AND CLINICAL RELEVANCE:
Established adult non-CF bronchiectasis is characterised by luminal Th17 pathway activation, however this pathway may be relatively less important than activation of non-antigen-specific innate neutrophilic immunity
Effect of kinematics on final state interactions in (e,e'p) reactions
Recent data from experiment E97-006 at TJNAF using the 12C(e,e'p) reaction at
very large missing energies and momenta are compared to a calculation of
two-step rescattering.
A comparison between parallel and perpendicular kinematics suggests that the
effects of final state interactions can be strongly reduced in the former case.Comment: 10 pages, 3 figures, submitted to LP
Measurement of the Induced Proton Polarization P_n in the 12C(e,e'\vec{p}) Reaction
The first measurements of the induced proton polarization, P_n, for the 12C
(e,e'\vec{p}) reaction are reported. The experiment was performed at quasifree
kinematics for energy and momentum transfer (\omega,q) \approx (294 MeV, 756
MeV/c) and sampled a recoil momentum range of 0-250 MeV/c. The induced
polarization arises from final-state interactions and for these kinematics is
dominated by the real part of the spin-orbit optical potential. The
distorted-wave impulse approximation provides good agreement with data for the
1p_{3/2} shell. The data for the continuum suggest that both the 1s_{1/2} shell
and underlying l > 1 configurations contribute.Comment: 5 pages LaTeX, 2 postscript figures, accepted by Physical Reveiw
Letter
Quantum Effects in the Mechanical Properties of Suspended Nanomechanical Systems
We explore the quantum aspects of an elastic bar supported at both ends and
subject to compression. If strain rather than stress is held fixed, the system
remains stable beyond the buckling instability, supporting two potential
minima. The classical equilibrium transverse displacement is analogous to a
Ginsburg-Landau order parameter, with strain playing the role of temperature.
We calculate the quantum fluctuations about the classical value as a function
of strain. Excitation energies and quantum fluctuation amplitudes are compared
for silicon beams and carbon nanotubes.Comment: RevTeX4. 5 pages, 3 eps figures. Submitted to Physical Review Letter
Intrinsic thermal vibrations of suspended doubly clamped single-wall carbon nanotubes
We report the observation of thermally driven mechanical vibrations of
suspended doubly clamped carbon nanotubes, grown by chemical vapor deposition
(CVD). Several experimental procedures are used to suspend carbon nanotubes.
The vibration is observed as a blurring in images taken with a scanning
electron microscope. The measured vibration amplitudes are compared with a
model based on linear continuum mechanics.Comment: pdf including figures, see:
http://www.unibas.ch/phys-meso/Research/Papers/2003/NT-Thermal-Vibrations.pd
A Truncated Waveguide Phase Shifter
The design, fabrication and performance of a simple phase shifter based upon truncated circular and square waveguides is presented. An emphasis is placed upon validation of simple analytical formulae that describe the propagation properties of the structure. A test device is prototyped at approximately 40GHz; however, the concepts explored can be directly extended to millimeter and submillimeter applications
The Drell-Hearn-Gerasimov Sum Rule
The Drell-Hearn-Gerasimov (DHG) sum rule relates the helicity structure of
the photoabsorption cross section to the anomalous magnetic moment of the
nucleon. It is based on Lorentz and gauge invariance, crossing symmetry,
causality and unitarity. A generalized DHG sum rule my be derived for virtual
photons. At low momentum transfer this generalized sum rule is saturated by the
resonance region, at high momentum transfer it may be expressed by the parton
spin distributions measured in deep inelastic scattering. The
longitudinal-transverse interference determines the Cottingham sum rule, which
is related to the electric and magnetic form factors over the whole range of
momentum transfer.Comment: 20 pages LATEX plus 12 figures (available by fax from the author
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