Glucocorticoid receptor expression in human bronchial epithelial cells: effects of smoking and COPD.

Previously, we found that inflammatory mediators modulated the number and binding affinity of glucocorticoid receptors (GR) in human bronchial epithelial cell lines. In this study we investigated whether smoking and chronic obstructive pulmonary disease (COPD), both characterized by airway inflammation with increased levels of inflammatory mediators, affect GR characteristics in cultured human bronchial epithelial cells (HBEC). A statistically significant difference was found between the dissociation constant (Kd) values in HBEC from smoking (Kd = 0.98+/-0.08 nM; n = 6) and nonsmoking controls (Kd = 0.76+/-0.10 nM, P = 0.03; n = 5), but no significant difference was found between the mean number of binding sites. Our results are the first indication that cultured HBEC from smokers possess GR with a lower binding affinity. This may result from the inflammation found in the airways from smokers. Furthermore, these results provide further evidence that the bronchial epithelium may be an actual target for inhaled glucocorticoid therapy

Local science and media engagement on climate change

Climate scientists can do a better job of communicating their work to local communities and reignite interest in the issue. Local media outlets provide a unique opportunity to build a platform for scientists to tell their stories and engage in a dialogue with people currently outside the 'climate bubble'

Thermal conductivity in harmonic lattices with random collisions

We review recent rigorous mathematical results about the macroscopic behaviour of harmonic chains with the dynamics perturbed by a random exchange of velocities between nearest neighbor particles. The random exchange models the effects of nonlinearities of anharmonic chains and the resulting dynamics have similar macroscopic behaviour. In particular there is a superdiffusion of energy for unpinned acoustic chains. The corresponding evolution of the temperature profile is governed by a fractional heat equation. In non-acoustic chains we have normal diffusivity, even if momentum is conserved.Comment: Review paper, to appear in the Springer Lecture Notes in Physics volume "Thermal transport in low dimensions: from statistical physics to nanoscale heat transfer" (S. Lepri ed.

Expression of lipocortins in human bronchial epithelial cells: effects of IL-1β , TNF-α, LPS and dexamethasone

In this study, we investigated the expression of lipocortin I and II (annexin I and I in the human bronchial epithelium, both in vivo and in vitro. A clear expression of lipocortin I and II protein was found in the epithelium in sections of bronchial tissue. In cultured human bronchial epithelial cells we demonstrated the expression of lipocortin I and II mRNA and protein using Northern blotting, FACScan analysis and ELISA. No induction of lipocortin I or II mRNA or protein was observed after incubation with dexamethasone. Stimulation of bronchial epithelial cells with IL-1β, TNF-α or LPS for 24 h did not affect the lipocortin I or II mRNA or protein expression, although PGE2 and 6-keto-PGF1α production was significantly increased. This IL-1β- and LPS-mediated increase in eicosanoids could be reduced by dexamethasone, but was not accompanied by an increase in lipocortin I or II expression. In human bronchial epithelial cells this particular glucocorticoid action is not mediated through lipocortin I or II induction

Aphid and Plant Volatiles Induce Oviposition in an Aphidophagous Hoverfly

Episyrphus balteatus DeGeer (Diptera, Syrphidae) is an abundant and efficient aphid-specific predator. We tested the electroantennographic (EAG) response of this syrphid fly to the common aphid alarm pheromone, (E)-β-farnesene (EβF), and to several plant volatiles, including terpenoids (mono- and sesquiterpenes) and green leaf volatiles (C6 and C9 alcohols and aldehydes). Monoterpenes evoked significant EAG responses, whereas sesquiterpenes were inactive, except for the aphid alarm pheromone (EβF). The most pronounced antennal responses were elicited by six and nine carbon green leaf alcohols and aldehydes [i.e., (Z)-3-hexenol, (E)-2-hexenol, (E)-2-hexenal, and hexanal]. To investigate the behavioral activity of some of these EAG-active compounds, E. balteatus females were exposed to R-(+)-limonene (monoterpene), (Z)-3-hexenol (green leaf alcohol), and EβF (sesquiterpene, common aphid alarm pheromone). A single E. balteatus gravid female was exposed for 10 min to an aphid-free Vicia faba plant that was co-located with a semiochemical dispenser. Without additional semiochemical, hoverfly females were not attracted to this plant, and no oviposition was observed. The monoterpene R-(+)-limonene did not affect the females’ foraging behavior, whereas (Z)-3-hexenol and EβF increased the time of flight and acceptance of the host plant. Moreover, these two chemicals induced oviposition on aphid-free plants, suggesting that selection of the oviposition site by predatory hoverflies relies on the perception of a volatile blend composed of prey pheromone and typical plant green leaf volatiles

Conserved Odorant-Binding Proteins from Aphids and Eavesdropping Predators

Background: The sesquiterpene (E)-ß-farnesene is the main component of the alarm pheromone system of various aphid species studied to date, including the English grain aphid, Sitobion avenae. Aphid natural enemies, such as the marmalade hoverfly Episyrphus balteatus and the multicolored Asian lady beetle Harmonia axyridis, eavesdrop on aphid chemical communication and utilize (E)-ß-farnesene as a kairomone to localize their immediate or offspring preys. These aphidpredator systems are important models to study how the olfactory systems of distant insect taxa process the same chemical signal. We postulated that odorant-binding proteins (OBPs), which are highly expressed in insect olfactory tissues and involved in the first step of odorant reception, have conserved regions involved in binding (E)-ß-farnesene. Methodology: We cloned OBP genes from the English grain aphid and two major predators of this aphid species. We then expressed these proteins and compare their binding affinities to the alarm pheromone/kairomone. By using a fluorescence reporter, we tested binding of (E)-ß-farnesene and other electrophysiologically and behaviorally active compounds, including a green leaf volatile attractant. Conclusion: We found that OBPs from disparate taxa of aphids and their predators are highly conserved proteins, with apparently no orthologue genes in other insect species. Properly folded, recombinant proteins from the English grain aphid, SaveOBP3, and the marmalade hoverfly, EbalOBP3, specifically bind (E)-ß-farnesene with apparent high affinity. For the firs

Hypermethylated-capped selenoprotein mRNAs in mammals.

Mammalian mRNAs are generated by complex and coordinated biogenesis pathways and acquire 5'-end m7G caps that play fundamental roles in processing and translation. Here we show that several selenoprotein mRNAs are not recognized efficiently by translation initiation factor eIF4E because they bear a hypermethylated cap. This cap modification is acquired via a 5'-end maturation pathway similar to that of the small nucle(ol)ar RNAs (sn- and snoRNAs). Our findings also establish that the trimethylguanosine synthase 1 (Tgs1) interacts with selenoprotein mRNAs for cap hypermethylation and that assembly chaperones and core proteins devoted to sn- and snoRNP maturation contribute to recruiting Tgs1 to selenoprotein mRNPs. We further demonstrate that the hypermethylated-capped selenoprotein mRNAs localize to the cytoplasm, are associated with polysomes and thus translated. Moreover, we found that the activity of Tgs1, but not of eIF4E, is required for the synthesis of the GPx1 selenoprotein in vivo

Anomalous Heat Conduction and Anomalous Diffusion in Low Dimensional Nanoscale Systems

Thermal transport is an important energy transfer process in nature. Phonon is the major energy carrier for heat in semiconductor and dielectric materials. In analogy to Ohm's law for electrical conductivity, Fourier's law is a fundamental rule of heat transfer in solids. It states that the thermal conductivity is independent of sample scale and geometry. Although Fourier's law has received great success in describing macroscopic thermal transport in the past two hundreds years, its validity in low dimensional systems is still an open question. Here we give a brief review of the recent developments in experimental, theoretical and numerical studies of heat transport in low dimensional systems, include lattice models, nanowires, nanotubes and graphenes. We will demonstrate that the phonon transports in low dimensional systems super-diffusively, which leads to a size dependent thermal conductivity. In other words, Fourier's law is breakdown in low dimensional structures

Conservative treatment of a comminuted cervical fracture in a racehorse

The 'classical' or 'Hangman' neck fracture involves the odontoid peg (process) of the second cervical vertebra (C2), and is described as an axial, dens or odontoid peg fracture in both the veterinary and human literature. Possible surgical treatment in both foals and adult horses requires a technique that allows decompression, anatomical alignment and stabilisation of the odontoid fracture. A limited number of surgical cases in foals have been reported in literature, but never in an adult horse. A mature Irish Thoroughbred racehorse was diagnosed with a type 2a odontoid peg fracture. Clinical signs included reluctance to move the head and neck, a left hind limb lameness and a neurological status of grade 2. The horse was treated conservatively and raced successfully five months after the diagnosed injury