Ligation of protease-activated receptor 1 enhances alpha(v)beta(6) integrin-dependent TGF-beta activation and promotes acute lung injury

Activation of latent TGF-beta by the alpha(v)beta(6) integrin is a critical step in the development of acute lung injury. However, the mechanism by which a alpha(v)beta(6)-mediated TGF-beta activation is regulated has not been identified. We show that thrombin, and other agonists of protease-activated receptor 1(PAR1), activate TGF-beta in an alpha(v)beta(6) integrin-specific manner. This effect is PART specific and is mediated by RhoA and Rho kinase. Intratracheal instillation of the PART-specific peptide TFLLRN increases lung edema during high-tidal-volume ventilation, and this effect is completely inhibited by a blocking antibody against the alpha(v)beta(6) integrin. Instillation of TFLLRN during high-tidal-volume ventilation is associated with increased pulmonary TGF-beta activation; however, this is not observed in Itgb6(-/-) mice. Furthermore, Itgb6(-/-) mice are also protected from ventilator-induced lung edema. We also demonstrate that pulmonary edema and TGF-beta activity are similarly reduced in Par1(-/-) mice following bleomycin-induced lung injury. These results suggest that PART-mediated enhancement of a alpha(v)beta(6)-dependent TGF-beta activation could be one mechanism by which activation of the coagulation cascade contributes to the development of acute lung injury, and they identify PART and the alpha(v)beta(6) integrin as potential therapeutic targets in this condition

Characterization of damage in shielding structures of space vehicles under hypervelocity impact

6th Asia Pacific Workshop on Structural Health Monitoring, APWSHM, Hobart, Tasmania, Australia, 7-9 December 2016Version of RecordPublishe

Design of bolted side-plated reinforced-concrete beams with partial interaction

Existing reinforced-concrete (RC) beams can be effectively strengthened by anchoring steel plates to the side faces of the beams using bolts, which is known as the bolted side-plating (BSP) technique. Previous studies have found that the performance of BSP beams is primarily controlled by the degree of partial interaction at the steel-RC interface, which can be conveniently quantified by the strain and curvature factors. In this paper, a new simplified flexural design procedure for BSP beams taking into account partial interaction is presented. Some optimum ranges of strain and curvature factors are first introduced to the flexural design of BSP beams. By ensuring the flexural capacity of a BSP beam is higher than the design moment, the preliminary size of steel plates and the arrangement of bolts can be determined. Following this, the maximum design slips and minimum design strain and curvature factors are calculated and back-checked to ensure the target flexural capacity of the BSP beam has been achieved. An example is presented to illustrate the effectiveness of the optimised design method for BSP beams, considering the effect of partial interaction under realistic loading conditions.published_or_final_versio

Reduction of bacterial adhesion on titanium-doped diamond-like carbon coatings

A range of titanium doped diamond like carbon (Ti-DLC) coatings with different Ti contents were prepared on stainless steel substrates using a plasma-enhanced chemical vapour deposition technique. It was found that both the electron donor surface energy and the surface roughness of the Ti-DLC coatings increased with increasing Ti contents in the coatings. Bacterial adhesion to the coatings was evaluated against Escherichia coli WT F1693 and Pseudomonas aeruginosa ATCC 33347. The experimental data showed that bacterial adhesion decreased with the increases of the Ti content, the electron donor surface energy and surface roughness of the coatings, while the bacterial removal percentage increased with the increases of these parameters. The Ti-DLC coatings reduced bacterial attachment by up to 75% and increased bacterial detachment from 15% to 45%, compared with stainless steel control

Secondary structure in the core of amyloid fibrils formed from human βm and its truncated variant Δn6

Amyloid fibrils formed from initially soluble proteins with diverse sequences are associated with an array of human diseases. In the human disorder, dialysis-related amyloidosis (DRA), fibrils contain two major constituents, full-length human β-microglobulin (hβm) and a truncation variant, ΔN6 which lacks the N-terminal six amino acids. These fibrils are assembled from initially natively folded proteins with an all antiparallel β-stranded structure. Here, backbone conformations of wild-type hβm and ΔN6 in their amyloid forms have been determined using a combination of dilute isotopic labeling strategies and multidimensional magic angle spinning (MAS) NMR techniques at high magnetic fields, providing valuable structural information at the atomic-level about the fibril architecture. The secondary structures of both fibril types, determined by the assignment of ∼80% of the backbone resonances of these 100- and 94-residue proteins, respectively, reveal substantial backbone rearrangement compared with the location of β-strands in their native immunoglobulin folds. The identification of seven β-strands in hβm fibrils indicates that approximately 70 residues are in a β-strand conformation in the fibril core. By contrast, nine β-strands comprise the fibrils formed from ΔN6, indicating a more extensive core. The precise location and length of β-strands in the two fibril forms also differ. The results indicate fibrils of ΔN6 and hβm have an extensive core architecture involving the majority of residues in the polypeptide sequence. The common elements of the backbone structure of the two proteins likely facilitates their ability to copolymerize during amyloid fibril assembly

Characterizing hypervelocity impact (HVI)-induced pitting damage using active guided ultrasonic waves : from linear to nonlinear

2016-2017 > Academic research: refereed > Publication in refereed journal201804_a bcmaVersion of RecordPublishe

Development of a web-based insulin decision aid for the elderly: usability barriers and guidelines

In recent years, researchers have attempted to shift patient decision aids (PDAs) from paper-based to web-based to increase its accessibility. Insulin decision aids help diabetes patients, most of whom are elderly to make an informed decision to start insulin. However, the lack of usability guidelines applicable for such target group causes developers to struggle to answer the challenging question ‘How can such web service be made usable, and, ultimately, acceptable and accessible for elderly patients?’. Hence, the purpose of this study is to identify the common usability requirements that may facilitate good practices to empower elderly diabetes patients in utilizing a web-based insulin decision aid for their benefit. We set out an approach to use prototyping and retrospective think-aloud techniques to explore web usability barriers that elderly patients may encounter when using an insulin decision aid web site and use the feedback for improving the prototype. Usability requirements were captured iteratively through scoping, brainstorming, prototype, testing and evaluating. The study suggests that the insights from experts and users are equally important to assure the validity of the identified usability guidelines; they reflect the accessibility needs of the aging community while complementing the key requirements of an insulin decision aid. The study contributes to recommend web usability guidelines backed by a series of expert and user evaluations which could be a proactive resource to improve usability, acceptability and accessibility of online insulin decision aids for elderly with diabetes

Accuracy and repeatability of wrist joint angles in boxing using an electromagnetic tracking system

© 2019, The Author(s). The hand-wrist region is reported as the most common injury site in boxing. Boxers are at risk due to the amount of wrist motions when impacting training equipment or their opponents, yet we know relatively little about these motions. This paper describes a new method for quantifying wrist motion in boxing using an electromagnetic tracking system. Surrogate testing procedure utilising a polyamide hand and forearm shape, and in vivo testing procedure utilising 29 elite boxers, were used to assess the accuracy and repeatability of the system. 2D kinematic analysis was used to calculate wrist angles using photogrammetry, whilst the data from the electromagnetic tracking system was processed with visual 3D software. The electromagnetic tracking system agreed with the video-based system (paired t tests) in both the surrogate ( 0.9). In the punch testing, for both repeated jab and hook shots, the electromagnetic tracking system showed good reliability (ICCs > 0.8) and substantial reliability (ICCs > 0.6) for flexion–extension and radial-ulnar deviation angles, respectively. The results indicate that wrist kinematics during punching activities can be measured using an electromagnetic tracking system

Seeking legitimacy through CSR: Institutional Pressures and Corporate Responses of Multinationals in Sri Lanka

Arguably, the corporate social responsibility (CSR) practices of multinational enterprises (MNEs) are influenced by a wide range of both internal and external factors. Perhaps most critical among the exogenous forces operating on MNEs are those exerted by state and other key institutional actors in host countries. Crucially, academic research conducted to date offers little data about how MNEs use their CSR activities to strategically manage their relationship with those actors in order to gain legitimisation advantages in host countries. This paper addresses that gap by exploring interactions between external institutional pressures and firm-level CSR activities, which take the form of community initiatives, to examine how MNEs develop their legitimacy-seeking policies and practices. In focusing on a developing country, Sri Lanka, this paper provides valuable insights into how MNEs instrumentally utilise community initiatives in a country where relationship-building with governmental and other powerful non-governmental actors can be vitally important for the long-term viability of the business. Drawing on neo-institutional theory and CSR literature, this paper examines and contributes to the embryonic but emerging debate about the instrumental and political implications of CSR. The evidence presented and discussed here reveals the extent to which, and the reasons why, MNEs engage in complex legitimacy-seeking relationships with Sri Lankan institutions

Genetic determinants of co-accessible chromatin regions in activated T cells across humans.

Over 90% of genetic variants associated with complex human traits map to non-coding regions, but little is understood about how they modulate gene regulation in health and disease. One possible mechanism is that genetic variants affect the activity of one or more cis-regulatory elements leading to gene expression variation in specific cell types. To identify such cases, we analyzed ATAC-seq and RNA-seq profiles from stimulated primary CD4+ T cells in up to 105 healthy donors. We found that regions of accessible chromatin (ATAC-peaks) are co-accessible at kilobase and megabase resolution, consistent with the three-dimensional chromatin organization measured by in situ Hi-C in T cells. Fifteen percent of genetic variants located within ATAC-peaks affected the accessibility of the corresponding peak (local-ATAC-QTLs). Local-ATAC-QTLs have the largest effects on co-accessible peaks, are associated with gene expression and are enriched for autoimmune disease variants. Our results provide insights into how natural genetic variants modulate cis-regulatory elements, in isolation or in concert, to influence gene expression