Development of a nitric oxide measurement method in tissue media

2012 Spring.Includes bibliographical references.Nitric oxide (NO) is involved in many biological pathways such as vasodilatation and cellular migration. The biological roles of NO have been most heavily investigated using cell and tissue culture models. The limitations with current analytical measurement methods used most commonly with these studies, however, are that they often do not record in real-time or measure NO directly. This makes it difficult to understand the concentration dependent response activity of NO. To overcome these limitations, a measurement method has been developed that enables the real-time measurement of NO in buffered tissue media (pH 7.4, buffered with CO2 gas, 37 °C). The design of our system included multi-volume custom sample cells with a pH probe and multiple gas supply inputs, a flow regulated CO2 gas system and a chemiluminescence detector. Results demonstrated the expected first-order NO release kinetics using a model NO donor (MAHMA/NO) in phosphate buffered saline (PBS) over a specified volume range. The following half-lives were found: 63±2 s (2 mL), 65±2 s (6 mL), 63±4 s (8 mL) and 67±9 s (10 mL). Using this method at these buffer volumes, an experiment was conducted using 11 mM MAHMA/NO stock used to demonstrate that NO release was linearly proportional with respect to buffer volume with a linear fit of R2 =0.9936. The linearity of NO release allowed NO release measurements of 4.4 x 10-7 M MAHMA/NO concentration in 10 mL PBS achieving NO recovery of 117±2 and MAHMA/NO decomposition half-lives 66±2. The analysis of a 10-7 M MAHMA/NO was not measurable previously using other chemiluminescence methods. Subsequent results in tissue media buffered with 5% CO2 at a controlled rate of 20 mL/min showed statistically similar kinetic rates 68±5 s (2 mL) to that of the PBS, demonstrating the ability to measure NO in real time under tissue conditions. The simultaneous pH measurements confirmed that the pH was constant at 7.4 during the NO release portion of the experiment, an important aspect to maintain accurate kinetics. Using this method for NO release measurement in tissue media, another NO donor, DETA/NO, was used to look at steady-state release for 1.5 h. The total NO release was 0.12±0.02 (nmol) and the NO release rate was 22±3 (fmol/s). This is the first analytical measurement method that enables detection of NO release from NO donors in buffered tissue media method mimicking in vitro condition

The Development of a Real-Time Movement Sonification Exergame for Body-Weight Squat Training

Participating in physical activities is often difficult for individuals living with blindness or other visual impairments. The use of exergames has shown promise in affording these individuals engaging and novel methods for participation in physical activity. Specifically, movement sonification is one method shown to be reliable in providing guidance and helping users orient their bodies in space. Through this research we aim to develop an auditory-only exergame that provides augmented feedback, using a combination of verbal instruction and real-time movement sonification, for low to no vision users to learn to perform body-weight squat movements correctly and safely. We anticipate that this research will assist in further establishing the importance of movement sonification feedback for better exercise training and comprehension in physical activity when no visual input is present

The AMP-Foot 3, new generation propulsive prosthetic feet with explosive motion characteristics: design and validation

The last decades, rehabilitation has become a challenging context for mechatronical engineering. From the state-of-the-art it is seen that the field of prosthetics offers very promising perspectives to roboticist. Today’s prosthetic feet tend to improve amputee walking experience by delivering the necessary push-off forces while walking. Therefore, several new types of (compliant) actuators are developed in order to fulfill the torque and power requirements of a sound ankle-foot complex with minimized power consumption. At the Vrije Universiteit Brussel, the Robotics and Multibody Mechanics research group puts a lot of effort in the design and development of new bionic feet. In 2013, the Ankle Mimicking Prosthetic (AMP-) Foot 2, as a proof-of-concept, showed the advantage of using the explosive elastic actuator capable of delivering the full ankle torques ( $$\pm 120$$ ± 120  Nm) and power ( $$\pm 250$$ ± 250 W) with only a 60 W motor. In this article, the authors present the AMP-Foot 3, using an improved actuation method and using two locking mechanisms for improved energy storage during walking. The article focusses on the mechanical design of the device and validation of its working principle.This work and the publication costs of this article have been funded by the European Commissions 7th Framework Program as part of the project Cyberlegs under grant no. 287894 and by the European Commission ERC Starting grant SPEAR under grant no. 337596.Peer reviewe

Language and teaching in multilingual schools: a Foucauldian discourse analysis of primary school teachers' talk about their teaching practice in multilingual schools

This study explores discourses in teachers’ talk about their teaching practice in multilingual schools, with a focus on discourses relating to language. The study adopts a Foucauldian approach to discourse and views social structures and institutions as formed in discourse specific to a social and historical context. Semi-structured interviews were carried out with teachers in schools where a high proportion of pupils spoke a first language other than English. Eight teachers were interviewed, and the data were analysed using Foucauldian Discourse Analysis. The findings indicate that in the teachers’ talk there are discourses of a monolingual education system where other languages are used to support pupils to transition to using English and for recognising culture in non-curricular activities. The discourse is contradictory, as the structures of teaching are described as suitable for all, yet as inaccessible and disadvantageous to pupils learning EAL. The discourse also excludes a number of alternative discourses including the regular use of first languages during curricular activities. Disciplinary powers are identified in the standard curriculum structures, and they are discussed in relation to how they constrain practice in multilingual schools. Lastly, there is a discussion of implications for educational psychology practice and ideas for future research

Acetylcholinesterase Isozyme Banding May Be Useful in Revealing Heart Failure

Cardiopathology provides insights into the functioning heart and its circulatory vessels. Recent studies have proposed a critical role for esterases in heart failure (Dunlop et. al. 2003). Evidence points to a loss of vagal (parasympathetic) control and a parallel increase in sympathetic activity as the disease progresses. Other researchers (Ojaimi et.al. 2007) used microarray technique on tissues from canine paced heart failure models to show selective re-regulation of genes as the pathology developed. To further explore this connection, a pilot project comparing the enzyme acetylcholinesterase (AChE) from normal (N) and heart failure (HF) specimens was designed. Non-denaturing polyacrylamide gel electrophoresis (PAGE) separated the isoenzyme components. Diazonium salts stained and identified the resulting enzyme/substrate banding patterns. The present study refines previous work by examining AChE activity of non-denatured protein from N and HF tissues. In addition, a variety of non-cardiac tissues and organs were examined to determine the extent of pathological changes in AChE isoenzymes

A creative health placement: challenging student nurses to learn creatively

This document is the Accepted Manuscript version of a published work that appeared in final form in [Nursing Times]. To access the final edited and published work see https://www.nursingtimes.net/roles/nurse-educators/creative-health-challenging-student-nurses-to-learn-from-the-arts-11-03-2024/There is a drive to promote population health as a preventative measure. The use of creative health has been advocated to relieve pressures on healthcare services, but this can only be achieved by greater awareness of and immersion in such practices. The creative health placement at the University of Chester responded to this need, offering 60 nursing students the experience of an arts-based practice learning placement and the chance to explore their personal wellbeing. Such learning presented a challenge for students, requiring them to reflect on their expectations of nursing placements and respond creatively to the healthcare issues facing our profession

Case Study on Human Walking during Wearing a Powered Prosthetic Device: Effectiveness of the System “Human-Robot”

It is known that force exchanges between a robotic assistive device and the end-user have a direct impact on the quality and performance of a particular movement task. This knowledge finds a special reflective importance in prosthetic industry due to the close human-robot collaboration. Although lower-extremity prostheses are currently better able to provide assistance as their upper-extremity counterparts, specific locomotion problems still remain. In a framework of this contribution the authors introduce the multibody dynamic modelling approach of the transtibial prosthesis wearing on a human body model. The obtained results are based on multibody dynamic simulations against the real experimental data using AMP-Foot 2.0, an energy efficient powered transtibial prosthesis for actively assisted walking of amputees