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Aim: The aim of this study was to investigate the activity of NLRP3 inflammasome and its effect on inducing severe pneumonia 1 week after influenza A virus (IAV) infection. Materials & methods: The expression levels of NLRP3, caspase-1 and IL-1β were assessed in murine macrophages stimulated with IAV. And the severity of viral pneumonia in mice was explored. Results & conclusion: The data showed that although the expression of NLRP3 diverged, activity of NLRP3 inflammasome was enhanced 1 week after IAV infection, and more severe viral pneumonia was associated with IL-1β in serum. It infers that enhanced activity of NLRP3 inflammasome induces augmented expression of IL-1β and severe pneumonia in a NLRP3-independent way, 1 week after IAV infection. Influenza A virus (IAV) infects lungs. Inflammasome is a complex of proteins in cells. It plays key role in IAV infection. We studied the role of NLRP3 inflammasome. The results are shown as below. The expression of IL-1β increased. Severer pneumonia was related with it. However, the expression of NLRP3 decreased. It diverged from that of IL-1β. Three conclusions were drawn. IAV infection activates NLRP3 inflammasome. Upregulation of IL-1β 1 week after infection induces severe pneumonia. It is independent of NLRP3. Data from biomedical research suggests that divergent activity and role of NLRP3 inflammasome during influenza A virus infection should be considered. [ABSTRACT FROM AUTHOR]

Molecular dynamics simulations were used to study the atomic mechanisms of deformation of nanocrystalline gold with 2.65–18 nm in grain size to explore the inverse Hall–Petch effect. Based on the mechanical responses, particularly the flow stress and the elastic-to-plastic transition, one can delineate three regimes: mixed (10–18 nm, dislocation activities and grain boundary sliding), inverse Hall-Petch (5–10 nm, grain boundary sliding), and super-soft (below 5 nm). As the grain size decreases, more grain boundaries present in the nanocrystalline solids, which block dislocation activities and facilitate grain boundary sliding. The transition from dislocation activities to grain boundary sliding leads to strengthening-then-softening due to grain size reduction, shown by the flow stress. It was further found that, samples with large grain exhibit pronounced yield, with the stress overshoot decrease as the grain size decreases. Samples with grain sizes smaller than 5 nm exhibit elastic-perfect plastic deformation without any stress overshoot, leading to the super-soft regime. Our simulations show that, during deformation, smaller grains rotate more and grow in size, while larger grains rotate less and shrink in size. [ABSTRACT FROM AUTHOR]

Multi-sectoral health care alliances (MHCAs) are organizations that bring together diverse stakeholders to work collaboratively to improve health and health care in local communities. MHCA awareness is a necessary condition for cultivating and sustaining coordinated efforts among participants to improve the quality of care in a community, yet little research has examined whether MHCAs have actually fostered high levels of awareness among participants or how they go about doing so. This mixed method study used quantitative data drawn from three rounds of survey data from MHCA participants to assess the degree of MHCA awareness. It also examined whether perceptions of leadership effectiveness and management style were associated with differences in awareness at the level of the individual alliance participant, member organizations, and the community at large. Interviews with participants examined the approaches undertaken by MHCAs to foster awareness among individuals, organizations, and the community at large as well as the challenges MHCAs confront in raising awareness at each of these different levels. Findings indicate higher levels of awareness among individual participants, while awareness was perceived to be lowest at the community level. Perceptions of leadership effectiveness exhibited the most robust relationships across these three levels; it was positively associated with individual- and community-level awareness. The qualitative analysis identified variations in the strategies being used and the challenges arising at the different levels and indicated that awareness building occurred sequentially across these levels, suggesting a need for more systemic approaches to promoting awareness of these alliances and their efforts. [ABSTRACT FROM AUTHOR]

In order to investigate the relationships between the stability of Cu complexes and the nitrification inhibition effects of corresponding ligands, the effects of 22 kinds of Cu (II) ligands and eight kinds of Cu (I) ligands were evaluated in three types of soil on nitrification potentials (NPs) under short-term incubation (5 h) and nitrification inhibitory rates (NIRs) under long-term incubation (14 d). The results showed that the inhibitory effect of Cu (II) or Cu (I) ligands on nitrification exhibited significant linear relationships (P< 0.01) with the logarithms of the first stability constants (lgK1) and the total stability constants (lgKf) of corresponding complexes. Furthermore, lgKfof Cu (II) complexes exhibited a greater linear correlation than the corresponding lgK1with the nitrification inhibition effects of the corresponding ligands; lgKfof Cu (I) complexes exhibited a steeper linear relationship than that of Cu (II) complexes with NPs or NIRs, and hence, nitrification inhibition effects of Cu (I) ligands almost doubled that of Cu (II) ligands when the lgKfvalues of Cu (I) and Cu (II) complexes have the same changes. [ABSTRACT FROM PUBLISHER]

We review a minimalist's reactive force field, reactive state summation (RSS) potential. The essence of RSS potential scheme is to model each reactive state by individual non-reactive force fields, then modulate each term by a reaction-coordinate-dependent weight function, finally sum together to obtain the reactive potential. Compared with existing reactive potentials, RSS potential is easier to formulate and parameterise and is computationally efficient, at the expense of lesser accuracy. Thus, RSS potential can be regarded as a ‘reactive Lennard-Jones’ potential. Three exemplary RSS potentials are described in the context of their respective chemical systems: RSS-nitrogen for modelling detonation, RSS-carbon for modelling pyrolysis of activated carbon and RSS-fuel-catalyst for modelling catalytic chemical reaction. [ABSTRACT FROM AUTHOR]

Butylidenephthalide is one of the major active components isolated from Rhizoma Chuanxiong. This paper describes a simple, rapid, specific and sensitive method for the quantification of butylidenephthalide in rat plasma and tissue distribution using a liquid-liquid extraction procedure followed by capillary gas chromatography-selected ion monitoring mode-mass spectrometry (GC-SIM-MS) analysis. The calibration curves were linear over the concentration ranging from 0.02-10.0 µg/mL (r > 0.99) for plasma samples and 0.18-7.25 µg/g (r > 0.99) for the tissue samples. The limit of quantification (LOQ) was 1.0 ng/mL or 1.0 ng/g (ten times signal/noise ratio). Within- and between-day precisions expressed as the relative standard deviation (RSD) for the method were 2.39-2.98% and 2.97-4.26%, respectively. The methods of recovery for all samples were greater than 80% at the low, medium, and high concentrations. The method has been successfully applied to a pharmacokinetics study in rats after an oral administration of Butylidenephthalide with a dose of 20.0 mg/kg. The main pharmacokinetic parameters obtained were Tmax = (0.22 ± 0.06) h, Cmax = (3 ± 1) µg/mL, AUC = (32 ± 6) h•µg/mL, and Ka = (8.5 ± 0.8)/h. The results showed that the butylidenephthalide was easily absorbed. The concentrations of butylidenephthalide in rat kidney, lung, heart, and cerebellum were higher than those in other organs. To determine free fraction in serum, samples were filtered using ultrafiltration membranes with a molecular weight cut-off of 10,000 Da and extracted using liquid-liquid extraction. The extracts were evaporated and analyzed by GC-MS. The protein binding in rat plasma, human plasma, and human serum albumin were 83 ± 4%, 94 ± 3%, and 89 ± 3%, respectively. [ABSTRACT FROM AUTHOR]