Improved Alveolar Dynamics and Structure After Alveolar Epithelial Type II Cell Transplantation in Bleomycin Induced Lung Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a progressively and ultimately fatal lung disease. Previously it has been shown that intratracheal administration of alveolar epithelial type II cells (AE2C) in the animal model of bleomycin-induced pulmonary fibrosis is able to reverse fibrosis and restore surfactant protein levels. However, to date, it has not been evaluated whether these changes involve any improvement in alveolar dynamics. Consequently, the aim of the present work was to study lung physiology after AE2C transplantation at different time points during the development of injury and fibrosis. Lung fibrosis was induced by intratracheal instillation of bleomycin (4U/kg) in rat lungs. The animals were transplanted with AE2C (2.5 x 10(6) cells/animal) 3 or 7 days after bleomycin instillation. Assessments were done at day 7 and 14 after the induction of fibrosis to plot time dependent changes in lung physiology and mechanics. To assess the pressures and rates at which closed alveoli reopens invasive pulmonary tests using a small-animal mechanical ventilator (Flexivent (R), Scireq, Canada) including de-recruitability tests and forced oscillation technique as well as quasi-static pressure volume loops were performed. Afterwards lungs were fixed by vascular perfusion and subjected to design-based stereological evaluation at light and electron microscopy level. AE2C delivered during the lung injury phase (3 days) of the disease are only able to slightly recover the volume of AE2C and volume fraction of LB in AE2C. However, it did not show either positive effects regarding ventilated alveolar surface nor any increase of lung compliance. On the other hand, when AE2C are delivered at the beginning of the fibrotic phase (7 days after bleomycin instillation), an increased ventilated alveolar surface to control levels and reduced septal wall thickness can be observed. Moreover, transplanted animals showed better lung performance, with increased inspiratory capacity and compliance. In addition, a detailed analysis of surfactant active forms [mainly tubular myelin, lamellar body (LB)-like structures and multilamellar vesicles (MLV)], showed an effective recovery during the pro-fibrotic phase due to the healthy AE2C transplantation. In conclusion, AE2C transplantation during fibrogenic phases of the disease improves lung performance, structure and surfactant ultrastructure in bleomycin-induced lung fibrosis

AntagomiR directed against miR-20a restores functional BMPR2 signalling and prevents vascular remodelling in hypoxia-induced pulmonary hypertension

Aims Dysregulation of the bone morphogenetic protein receptor type 2 (BMPR2) is a hallmark feature that has been described in several forms of pulmonary hypertension. We recently identified the microRNA miR-20a within a highly conserved pathway as a regulator of the expression of BMPR2. To address the pathophysiological relevance of this pathway in vivo, we employed antagomiR-20a and investigated whether specific inhibition of miR-20a could restore functional levels of BMPR2 and, in turn, might prevent pulmonary arterial vascular remodelling. Methods and results For specific inhibition of miR-20a, cholesterol-modified RNA oligonucleotides (antagomiR-20a) were synthesized. The experiments in mice were performed by using the hypoxia-induced mouse model for pulmonary hypertension and animal tissues were analysed for right ventricular hypertrophy and pulmonary arterial vascular remodelling. Treatment with antagomiR-20a enhanced the expression levels of BMPR2 in lung tissues; moreover, antagomiR-20a significantly reduced wall thickness and luminal occlusion of small pulmonary arteries and reduced right ventricular hypertrophy. To assess BMPR2 signalling and proliferation, we performed in vitro experiments with human pulmonary arterial smooth muscle cells (HPASMCs). Transfection of HPASMCs with antagomiR-20a resulted in activation of downstream targets of BMPR2 showing increased activation of Id-1 and Id-2. Proliferation of HPASMCs was found to be reduced upon transfection with antagomiR-20a. Conclusion This is the first report showing that miR-20a can be specifically targeted in an in vivo model for pulmonary hypertension. Our data emphasize that treatment with antagomiR-20a restores functional levels of BMPR2 in pulmonary arteries and prevents the development of vascular remodellin

P-576: Differential effects of selective cyclooxygenase-2 inhibitors on endothelial function in salt-induced hypertension

In view of the ongoing controversy of potential differences in cardiovascular safety of selective COX-2 inhibitors (coxibs), we compared the effects of two different coxibs and a traditional NSAID on endothelial dysfunction, a well established surrogate of cardiovascular disease, in salt-induced hypertension. Salt-sensitive (DS) and salt-resistant (DR) Dahl rats were treated with a high-sodium diet (4% NaCl) for 56 days. From days 35 to 56, diclofenac (6 mg/kg/d; DS-diclofenac), rofecoxib (2 mg/kg/d; DS-rofecoxib), celecoxib (25 mg/kg/d; DS-celecoxib) or placebo (DS-placebo) were added to the chow. Vascular reactivity of isolated aortic rings was assessed by isometric tension recording. Blood pressure increased with high sodium diet in the DS-groups which was more pronounced after diclofenac and rofecoxib treatment (p<0.005 vs DS-placebo), but slightly blunted by celecoxib (p<0.001 vs DS-placebo). Sodium diet markedly reduced NO-mediated endothelium-dependent relaxations to acetylcholine (ACh, 10−10−10−5 mol/L) in untreated hypertensive rats (p<0.0001 vs DR-placebo). Relaxation to ACh improved after celecoxib (p<0.005 vs DS-placebo and DS-rofecoxib), but remained unchanged after rofecoxib and diclofenac treatment. Vasoconstriction after NOS inhibition with Nω-Nitro-L-Arginine Methyl Ester (10-4 mol/L) was blunted in DS rats (p<0.05 vs DR-placebo), normalized by celecoxib, but not affected by rofecoxib or diclofenac. Protein expression of eNOS was decreased in DS rats with a trend for increased eNOS levels in the DS-celecoxib group (97.8±25.6 vs 54.8±2.8 %, p=0.088 vs DS-placebo). Indicators of oxidative stress, 8-isoprostane levels, were elevated in untreated DS rats on 4% NaCl (6.55±0.58 vs 3.65±1.05 ng/ml, p<0.05) and normalized by celecoxib only (4.29±0.58 ng/ml), while SOD protein expression was decreased in DS rats and not affected by any treatment. Plasma levels of prostaglandines did not change during high sodium diet or any treatment. These data show that celecoxib, but not rofecoxib or diclofenac, improves endothelial dysfunction and reduces oxidative stress, thus pointing to differential effects of coxibs in salt-sensitive hypertension. Am J Hypertens (2004) 17, 243A-243A; doi: 10.1016/j.amjhyper.2004.03.65

Comparative evaluation of approaches in T.4.1-4.3 and working definition of adaptive module

The goal of this deliverable is two-fold: (1) to present and compare different approaches towards learning and encoding movements us- ing dynamical systems that have been developed by the AMARSi partners (in the past during the first 6 months of the project), and (2) to analyze their suitability to be used as adaptive modules, i.e. as building blocks for the complete architecture that will be devel- oped in the project. The document presents a total of eight approaches, in two groups: modules for discrete movements (i.e. with a clear goal where the movement stops) and for rhythmic movements (i.e. which exhibit periodicity). The basic formulation of each approach is presented together with some illustrative simulation results. Key character- istics such as the type of dynamical behavior, learning algorithm, generalization properties, stability analysis are then discussed for each approach. We then make a comparative analysis of the different approaches by comparing these characteristics and discussing their suitability for the AMARSi project

A Modular Toolkit for Distributed Interactions

We discuss the design, architecture, and implementation of a toolkit which supports some theories for distributed interactions. The main design principles of our architecture are flexibility and modularity. Our main goal is to provide an easily extensible workbench to encompass current algorithms and incorporate future developments of the theories. With the help of some examples, we illustrate the main features of our toolkit.Comment: In Proceedings PLACES 2010, arXiv:1110.385

Modulation of frontal EEG alpha oscillations during maintenance and emergence phases of general anaesthesia to improve early neurocognitive recovery in older patients: protocol for a randomised controlled trial

Background Postoperative delirium may manifest in the immediate post-anaesthesia care period. Such episodes appear to be predictive of further episodes of inpatient delirium and associated adverse outcomes. Frontal electroencephalogram (EEG) findings of suppression patterns and low proprietary index values have been associated with postoperative delirium and poor outcomes. However, the efficacy of titrating anaesthesia to proprietary index targets for preventing delirium remains contentious. We aim to assess the efficacy of two strategies which we hypothesise could prevent post-anaesthesia care unit (PACU) delirium by maximising the alpha oscillation observed in frontal EEG channels during the maintenance and emergence phases of anaesthesia. Methods This is a 2 × 2 factorial, double-blind, stratified, randomised control trial of 600 patients. Eligible patients are those aged 60 years or over who are undergoing non-cardiac, non-intracranial, volatile-based anaesthesia of expected duration of more than 2 h. Patients will be stratified by pre-operative cognitive status, surgery type and site. For the maintenance phase of anaesthesia, patients will be randomised (1:1) to an alpha power-maximisation anaesthesia titration strategy versus standard care avoiding suppression patterns in the EEG. For the emergence phase of anaesthesia, patients will be randomised (1:1) to early cessation of volatile anaesthesia and emergence from an intravenous infusion of propofol versus standard emergence from volatile anaesthesia only. The primary study outcomes are the power of the frontal alpha oscillation during the maintenance and emergence phases of anaesthesia. Our main clinical outcome of interest is PACU delirium. Discussion This is a largely exploratory study; the extent to which EEG signatures can be modified by titration of pharmacological agents is not known. The underlying concept is maximisation of anaesthetic efficacy by individualised drug titration to a clearly defined EEG feature. The interventions are already clinically used strategies in anaesthetic practice, but have not been formally evaluated. The addition of propofol during the emergence phase of volatile-based general anaesthesia is known to reduce emergence delirium in children; however, the efficacy of this strategy in older patients is not known. Trial registration. Australian and New Zealand Clinical Trial Registry, ID: 12617001354370. Registered on 27/09/2017

Channels as Objects in Concurrent Object-Oriented Programming

There is often a sort of a protocol associated to each class, stating when and how certain methods should be called. Given that this protocol is, if at all, described in the documentation accompanying the class, current mainstream object-oriented languages cannot provide for the verification of client code adherence against the sought class behaviour. We have defined a class-based concurrent object-oriented language that formalises such protocols in the form of usage types. Usage types are attached to class definitions, allowing for the specification of (1) the available methods, (2) the tests clients must perform on the result of methods, and (3) the object status - linear or shared - all of which depend on the object's state. Our work extends the recent approach on modular session types by eliminating channel operations, and defining the method call as the single communication primitive in both sequential and concurrent settings. In contrast to previous works, we define a single category for objects, instead of distinct categories for linear and for shared objects, and let linear objects evolve into shared ones. We introduce a standard sync qualifier to prevent thread interference in certain operations on shared objects. We formalise the language syntax, the operational semantics, and a type system that enforces by static typing that methods are called only when available, and by a single client if so specified in the usage type. We illustrate the language via a complete example.Comment: In Proceedings PLACES 2010, arXiv:1110.385

Deformation Mechanisms, Microstructures, and Seismic Anisotropy of Wadsleyite in the Earth's Transition Zone

Wadsleyite is the dominant mineral of the upper portion of the Earth's mantle transition zone (MTZ). As such, understanding plastic deformation of wadsleyite is relevant for the interpretation of observations of seismic signals from this region in terms of mantle flow. Despite its relevance, however, the deformation mechanisms of wadsleyite and their effects on microstructures and anisotropy are still poorly understood. Here, we present the results of new deformation experiments on polycrystalline wadsleyite at temperatures of 1400–1770 K and pressures between 12.3 and 20.3 GPa in the laser-heated diamond anvil cell. We rely on multigrain X-ray crystallography to follow the evolution of individual grain orientations and extract lattice preferred orientations at the sample scale at different steps of the experiments. A comparison of experimental results of our work and the literature with polycrystal plasticity simulations, indicates that ⟨111⟩{101} is the most active slip system of dislocations in wadsleyite at all investigated conditions. Secondary slip systems such as [001](010), [100](001), and [100]{0kl}, however, play a critical role in the resulting microstructures and their activity depends on both temperature and water content, from which we extract an updated deformation map of wadsleyite at MTZ conditions. Lastly, we propose several seismic anisotropy models of the upper part of the MTZ, depending on temperature, geophysical context, and levels of hydration that will be useful for the interpretation of seismic signals from the MTZ in terms of mantle flow and water conten

Arginine methylation of the B cell antigen receptor promotes differentiation

Signals processed through the B cell antigen receptor (BCR) control both the proliferation and differentiation of B lymphocytes. How these different signaling modes are established at the BCR is poorly understood. We show that a conserved arginine in the tail sequence of the Igα subunit of the BCR is methylated by the protein arginine methyltransferase 1. This modification negatively regulates the calcium and PI-3 kinase pathways of the BCR while promoting signals leading to B cell differentiation. Thus, Igα arginine methylation can play an important role in specifying the outcome of BCR signaling