672 research outputs found
Dynamic comparison between Daan real-time PCR and Cobas TaqMan for quantification of HBV DNA levels in patients with CHB
Oxidative stress in children late after Kawasaki disease: relationship with carotid atherosclerosis and stiffness
Background: Persistent arterial dysfunction in patients with a history of Kawasaki disease (KD) and an integral role of oxidative stress in the development of cardiovascular disease are increasingly recognized. We sought to test the hypothesis that oxidative stress is increased in KD patients and related to carotid atherosclerotic changes and stiffness. Methods: We compared the serum levels of oxidative stress biomarkers, carotid intima-media thickness (IMT), and carotid stiffness index among KD patients with coronary aneurysms (n = 32), those without coronary complications (n = 19), and controls (n = 32). Results: Compared with controls, patients with coronary aneurysms had significantly higher serum levels of malonaldehyde (2.62 ± 0.12 μM vs 2.22 ± 0.07 μM, p = 0.014) and hydroperoxides (26.50 ± 1.13 μM vs 22.50 ± 0.62 μM, p = 0.008). A linear trend of the magnitude of oxidative stress in relation to inflammatory damage was observed for malonaldehyde (p = 0.018) and hydroperoxides (p = 0.014) levels. Serum malonaldehyde and hydroperoxide levels correlated positively with carotid IMT (p < 0.001 and p = 0.034, respectively) and stiffness index (p = 0.001 and p = 0.021, respectively). Multiple linear regression analysis identified serum malonaldehyde level as a significant determinant of carotid IMT (β = 0.31, p = 0.006) and stiffness (β = 0.27, p = 0.008). Conclusion: Our findings suggestoxidative stress is increased in KD patients with coronary aneurysms and is associated with carotid intima-media thickening and stiffening. © 2008 Cheung et al; licensee BioMed Central Ltd.published_or_final_versio
Effect of thermal treatment on the growth, structure and luminescence of nitride-passivated silicon nanoclusters
Silicon nanoclusters (Si-ncs) embedded in silicon nitride films have been studied to determine the effects that deposition and processing parameters have on their growth, luminescent properties, and electronic structure. Luminescence was observed from Si-ncs formed in silicon-rich silicon nitride films with a broad range of compositions and grown using three different types of chemical vapour deposition systems. Photoluminescence (PL) experiments revealed broad, tunable emissions with peaks ranging from the near-infrared across the full visible spectrum. The emission energy was highly dependent on the film composition and changed only slightly with annealing temperature and time, which primarily affected the emission intensity. The PL spectra from films annealed for duration of times ranging from 2 s to 2 h at 600 and 800°C indicated a fast initial formation and growth of nanoclusters in the first few seconds of annealing followed by a slow, but steady growth as annealing time was further increased. X-ray absorption near edge structure at the Si K- and L3,2-edges exhibited composition-dependent phase separation and structural re-ordering of the Si-ncs and silicon nitride host matrix under different post-deposition annealing conditions and generally supported the trends observed in the PL spectra
Specific Inhibition of Phosphodiesterase-4B Results in Anxiolysis and Facilitates Memory Acquisition
Cognitive dysfunction is a core feature of dementia and a prominent feature in psychiatric disease. As non-redundant regulators of intracellular cAMP gradients, phosphodiesterases (PDE) mediate fundamental aspects of brain function relevant to learning, memory, and
higher cognitive functions. Phosphodiesterase-4B (PDE4B) is an important phosphodiesterase in the hippocampal formation, is a major Disrupted in Schizophrenia 1 (DISC1) binding partner and is itself a risk gene for psychiatric illness. To define the effects of specific inhibition of the PDE4B subtype, we generated mice with a catalytic domain mutant form of PDE4B (Y358C) that has decreased ability to hydrolyze cAMP. Structural modelling predictions of decreased function and impaired binding with DISC1 were confirmed in cell assays. Phenotypic characterization of the PDE4BY358C mice revealed facilitated phosphorylation of CREB, decreased binding to DISC1, and upregulation of DISC1 and β-Arrestin in hippocampus and amygdala. In behavioural assays, PDE4BY358C mice displayed decreased anxiety and increased exploration, as well as cognitive enhancement across several tests of learning and memory, consistent with synaptic changes including enhanced long-term potentiation and impaired depotentiation ex vivo.
PDE4BY358C mice also demonstrated enhanced neurogenesis. Contextual fear memory, though intact at 24 hours, was decreased at 7 days in PDE4BY358C mice, an effect replicated pharmacologically with a non-selective PDE4 inhibitor, implicating cAMP signalling by PDE4B in a very late phase of consolidation. No effect of the PDE4BY358C mutation was observed in the pre-pulse inhibition and forced swim tests. Our data establish specific inhibition of PDE4B as a promising therapeutic approach for disorders of cognition and anxiety, and a putative target for pathological fear memory
Adipokines, insulin resistance, metabolic syndrome, and breast cancer recurrence: a cohort study
Complete convergence and complete moment convergence for arrays of rowwise ANA random variables
Measurement of the Forward-Backward Asymmetry in the B -> K(*) mu+ mu- Decay and First Observation of the Bs -> phi mu+ mu- Decay
We reconstruct the rare decays , , and in a data sample
corresponding to collected in collisions at
by the CDF II detector at the Fermilab Tevatron
Collider. Using and decays we report the branching ratios. In addition, we report
the measurement of the differential branching ratio and the muon
forward-backward asymmetry in the and decay modes, and the
longitudinal polarization in the decay mode with respect to the squared
dimuon mass. These are consistent with the theoretical prediction from the
standard model, and most recent determinations from other experiments and of
comparable accuracy. We also report the first observation of the {\mathcal{B}}(B^0_s \to
\phi\mu^+\mu^-) = [1.44 \pm 0.33 \pm 0.46] \times 10^{-6}27 \pm 6B^0_s$ decay observed.Comment: 7 pages, 2 figures, 3 tables. Submitted to Phys. Rev. Let
Measurement of the Bottom-Strange Meson Mixing Phase in the Full CDF Data Set
We report a measurement of the bottom-strange meson mixing phase \beta_s
using the time evolution of B0_s -> J/\psi (->\mu+\mu-) \phi (-> K+ K-) decays
in which the quark-flavor content of the bottom-strange meson is identified at
production. This measurement uses the full data set of proton-antiproton
collisions at sqrt(s)= 1.96 TeV collected by the Collider Detector experiment
at the Fermilab Tevatron, corresponding to 9.6 fb-1 of integrated luminosity.
We report confidence regions in the two-dimensional space of \beta_s and the
B0_s decay-width difference \Delta\Gamma_s, and measure \beta_s in [-\pi/2,
-1.51] U [-0.06, 0.30] U [1.26, \pi/2] at the 68% confidence level, in
agreement with the standard model expectation. Assuming the standard model
value of \beta_s, we also determine \Delta\Gamma_s = 0.068 +- 0.026 (stat) +-
0.009 (syst) ps-1 and the mean B0_s lifetime, \tau_s = 1.528 +- 0.019 (stat) +-
0.009 (syst) ps, which are consistent and competitive with determinations by
other experiments.Comment: 8 pages, 2 figures, Phys. Rev. Lett 109, 171802 (2012
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