Inhibition of cyclooxygenase 2 expression by diallyl sulfide on joint inflammation induced by urate crystal and IL-1β

SummaryObjectiveInvestigation of the effects of diallyl sulfide (DAS), a garlic sulfur compound, on joint tissue inflammatory responses induced by monosodium urate (MSU) crystals and interleukin-1β (IL-1β).DesignThe HIG-82 synovial cell line was used to establish the experimental model and DAS regime. Primary cultures of articular chondrocytes and synovial fibroblasts obtained from patients undergoing joint replacement for osteoarthritis were used in experimental studies. Cyclooxygenase (COX) expression following MSU crystal and IL-1β stimulation with/without DAS co-incubation was assessed by reverse transcription-polymerase chain reaction (RT-PCR), western blotting, and immunocytochemistry and nuclear factor-kappa B (NF-κB) activation determined by electrophoretic mobility shift assay. Prostaglandin E2 (PGE2) production was measured by enzyme-linked immunosorbent assay (ELISA). DAS effects on COX gene expression in an MSU crystal-induced acute arthritis in rats were assessed by RT-PCR.ResultsMSU crystals upregulated COX-2 expression in HIG-82 cells and this was inhibited by co-incubation with DAS. DAS inhibited MSU crystal and IL-1β induced elevation of COX-2 expression in primary synovial cells and chondrocytes. Production of PGE2 induced by crystals was suppressed by DAS and celecoxib. MSU crystals had no effect on expression of COX-1 in synovial cells. NF-κB was activated by MSU crystals and this was blocked by DAS. Increased expression of COX-2 in synovium following intraarticular injection of MSU crystals in a rat model was inhibited by co-administration of DAS.ConclusionsDAS prevents IL-1β and MSU crystal induced COX-2 upregulation in synovial cells and chondrocytes and ameliorates crystal induced synovitis potentially through a mechanism involving NF-κB. Anti-inflammatory actions of DAS may be of value in treatment of joint inflammation

Ab-initio study of BaTiO3 surfaces

We have carried out first-principles total-energy calculations of (001) surfaces of the tetragonal and cubic phases of BaTiO3. Both BaO-terminated (type I) and TiO2-terminated (type II) surfaces are considered, and the atomic configurations have been fully relaxed. We found no deep-gap surface states for any of the surfaces, in agreement with previous theoretical studies. However, the gap is reduced for the type-II surface, especially in the cubic phase. The surface relaxation energies are found to be substantial, i.e., many times larger than the bulk ferroelectric well depth. Nevertheless, the influence of the surface upon the ferroelectric order parameter is modest; we find only a small enhancement of the ferroelectricity near the surface.Comment: 8 pages, two-column style with 4 postscript figures embedded. Uses REVTEX and epsf macros. Also available at http://www.physics.rutgers.edu/~dhv/preprints/index.html#pad_sur

Ab initio study of ferroelectric domain walls in PbTiO3

We have investigated the atomistic structure of the 180-degree and 90-degree domain boundaries in the ferroelectric perovskite compound PbTiO3 using a first-principles ultrasoft-pseudopotential approach. For each case we have computed the position, thickness and creation energy of the domain walls, and an estimate of the barrier height for their motion has been obtained. We find both kinds of domain walls to be very narrow with a similar width of the order of one to two lattice constants. The energy of the 90-dergree domain wall is calculated to be 35 mJ/m^2, about a factor of four lower than the energy of its 180-degree counterpart, and only a miniscule barrier for its motion is found. As a surprising feature we detected a small offset of 0.15-0.2 eV in the electrostatic potential across the 90-degree domain wall.Comment: 12 pages, with 9 postscript figures embedded. Uses REVTEX and epsf macros. Also available at http://www.physics.rutgers.edu/~dhv/preprints/bm_dw/index.htm

Liquid crystal self-assembly of random-sequence DNA oligomers

In biological systems and nanoscale assemblies, the self-association of DNA is typically studied and applied in the context of the evolved or directed design of base sequences that give complementary pairing, duplex formation, and specific structural motifs. Here we consider the collective behavior of DNA solutions in the distinctly different regime where DNA base sequences are chosen at random or with varying degrees of randomness. We show that in solutions of completely random sequences, corresponding to a remarkably large number of different molecules, e.g., approximately 1012 for random 20-mers, complementary still emerges and, for a narrowrange of oligomer lengths, produces a subtle hierarchical sequence of structured self-assembly and organization into liquid crystal (LC) phases. This ordering follows from the kinetic arrest of oligomer association into long-lived partially paired double helices, followed by reversible association of these pairs into linear aggregates that in turn condense into LC domains

Making things happen : a model of proactive motivation

Being proactive is about making things happen, anticipating and preventing problems, and seizing opportunities. It involves self-initiated efforts to bring about change in the work environment and/or oneself to achieve a different future. The authors develop existing perspectives on this topic by identifying proactivity as a goal-driven process involving both the setting of a proactive goal (proactive goal generation) and striving to achieve that proactive goal (proactive goal striving). The authors identify a range of proactive goals that individuals can pursue in organizations. These vary on two dimensions: the future they aim to bring about (achieving a better personal fit within one’s work environment, improving the organization’s internal functioning, or enhancing the organization’s strategic fit with its environment) and whether the self or situation is being changed. The authors then identify “can do,” “reason to,” and “energized to” motivational states that prompt proactive goal generation and sustain goal striving. Can do motivation arises from perceptions of self-efficacy, control, and (low) cost. Reason to motivation relates to why someone is proactive, including reasons flowing from intrinsic, integrated, and identified motivation. Energized to motivation refers to activated positive affective states that prompt proactive goal processes. The authors suggest more distal antecedents, including individual differences (e.g., personality, values, knowledge and ability) as well as contextual variations in leadership, work design, and interpersonal climate, that influence the proactive motivational states and thereby boost or inhibit proactive goal processes. Finally, the authors summarize priorities for future researc

The NuSTAR Extragalactic Survey: A First Sensitive Look at the High-energy Cosmic X-Ray Background Population

We report on the first 10 identifications of sources serendipitously detected by the Nuclear Spectroscopic Telescope Array (NuSTAR) to provide the first sensitive census of the cosmic X-ray background source population at gsim 10 keV. We find that these NuSTAR-detected sources are ≈100 times fainter than those previously detected at gsim 10 keV and have a broad range in redshift and luminosity (z = 0.020-2.923 and L 10-40 keV ≈ 4 × 1041-5 × 1045 erg s–1); the median redshift and luminosity are z ≈ 0.7 and L 10-40 keV ≈ 3 × 1044 erg s–1, respectively. We characterize these sources on the basis of broad-band ≈0.5-32 keV spectroscopy, optical spectroscopy, and broad-band ultraviolet-to-mid-infrared spectral energy distribution analyses. We find that the dominant source population is quasars with L 10-40 keV > 1044 erg s–1, of which ≈50% are obscured with N H gsim 1022 cm–2. However, none of the 10 NuSTAR sources are Compton thick (N H gsim 1024 cm–2) and we place a 90% confidence upper limit on the fraction of Compton-thick quasars (L 10-40 keV > 1044 erg s–1) selected at gsim 10 keV of lsim 33% over the redshift range z = 0.5-1.1. We jointly fitted the rest-frame ≈10-40 keV data for all of the non-beamed sources with L 10-40 keV > 1043 erg s–1 to constrain the average strength of reflection; we find R < 1.4 for Γ = 1.8, broadly consistent with that found for local active galactic nuclei (AGNs) observed at gsim 10 keV. We also constrain the host-galaxy masses and find a median stellar mass of ≈1011 M ☉, a factor ≈5 times higher than the median stellar mass of nearby high-energy selected AGNs, which may be at least partially driven by the order of magnitude higher X-ray luminosities of the NuSTAR sources. Within the low source-statistic limitations of our study, our results suggest that the overall properties of the NuSTAR sources are broadly similar to those of nearby high-energy selected AGNs but scaled up in luminosity and mass

Inter- and intra-observer reproducibility of CT-Leaman score by an independent core lab

To assess the reproducibility of CT-based Leaman score (CT-LeSc). CT-LeSc can non-invasively quantify total coronary atherosclerotic burden and is an independent long-term predictor of cardiac events. Its calculation however relies on the subjective assessment of lesions using coronary computed tomography angiography and therefore is subject to intra- and inter-observer variability. Inter-observer reproducibility was assessed by calculating the CT-LeSc in 50 patients randomly selected from the SYNTAX III REVOLUTION and ABSORB trials by two separate teams, each made up of two cardiologists, who reported results by consensus. For intra-observer reproducibility, the CT-LeSc was calculated in same 50 patients on two occasions eight weeks apart, by the same team of two cardiologists. The level of agreement was measured by the weighted kappa statistic, with intra- and inter-observer variability used to evaluate the CT-LeSc’s reproducibility. The variables evaluated by weighted kappa statistics were total number of lesions; number of calcified lesions; number of non-calcified lesions; number of mixed lesions; number of obstructive lesions; number of non-obstructive lesions; and the total CT-LeSc in increments of ten and five. During assessment of inter-observer variability the mean ± standard deviation (SD) CT-LeSc calculated by the first and second team was 15.36 ± 5.57 versus 15.24 ± 5.16. The mean of the differences (precision) was 0.97, with a SD (accuracy) 1.17. The inter-observer variability was lowest for Leaman score in increments of five (weighted kappa 0.93), and highest for the total number of calcified lesions (weighted kappa 0.66). During assessment of intra-observer variability, the mean ± SD CT-LeSc were 16.61 ± 5.28 versus 16.82 ± 5.55. The mean ± SD of the differences was 1.28 ± 1.02. The intra-observer variability was the lowest for Leaman score in increments of five (weighted kappa 0.93), and the highest for the total number of lesions and calcified lesions (weighted kappa 0.65). CT-LeSc has substantial to near-perfect agreement for reproducibility. Cardiolog

Knockdown of zebrafish Nav1.6 sodium channel impairs embryonic locomotor activities

[[abstract]]Although multiple subtypes of sodium channels are expressed in most neurons, the specific contributions of the individual sodium channels remain to be studied. The role of zebrafish Nav1.6 sodium channels in the embryonic locomotor movements has been investigated by the antisense morpholino (MO) knockdown. MO1 and MO2 are targeted at the regions surrounding the translation start site of zebrafish Nav1.6 mRNA. MO3 is targeted at the RNA splicing donor site of exon 2. The correctly spliced Nav1.6 mRNA of MO3 morphants is 6% relative to that of the wild-type embryos. Nav1.6-targeted MO1, MO2 and MO3 attenuate the spontaneous contraction, tactile sensitivity, and swimming in comparison with a scrambled morpholino and mutated MO3 morpholino. No significant defect is observed in the development of slow muscles, the axonal projection of primary motoneurons, and neuromuscular junctions. The movement impairments caused by MO1, MO2, and MO3 suggest that the function of Nav1.6 sodium channels is essential on the normal early embryonic locomotor activities.[[notice]]補正完畢[[journaltype]]國