Release of soluble metal ions from copper based dental alloys mesured by ICP-MS

Describes the release of soluble metal ions from copper based dental alloys mesured by ICP-MS. Presented at the annual congress of the british toxicology society

Confined compression of collagen hydrogels

Reconstituted collagen hydrogels are often used for in vitro studies of cell-matrix interaction and as scaffolds for tissue engineering. Understanding the mechanical and transport behaviours of collagen hydrogels is therefore extremely important, albeit difficult due to their very high water content (typically > 99.5%). In the present study the mechanical behaviour of collagen hydrogels in confined compression was investigated using biphasic theory (J. Biomech. Eng. 102 (1980) 73), to ascertain whether the technique is sufficiently sensitive to determine differences in the characteristics of hydrogels of between 0.2% and 0.4% collagen. Peak stress, equilibrium stress, aggregate modulus and hydraulic permeability of the hydrogels exhibited sensitivity to collagen content, demonstrating that the technique is clearly able to discriminate between hydrogels with small differences in collagen content and may also be sensitive to factors that affect matrix remodelling. The results also offer additional insight into the deformation-dependent permeability of collagen hydrogels. This study suggests that confined compression, together with biphasic theory, is a suitable technique for assessing the mechanical properties of collagen hydrogels

The use of proteomic techniques to explore the holistic effects of nutrients in vivo

The availability of ‘omics’ technologies is transforming scientific approaches to physiological problems from a reductionist viewpoint to that of a holistic viewpoint. This is of profound importance in nutrition, since the integration of multiple systems at the level of gene expression on the synthetic side through to metabolic enzyme activity on the degradative side combine to govern nutrient availability to tissues. Protein activity is central to the process of nutrition from the initial absorption of nutrients via uptake carriers in the gut, through to distribution and transport in the blood, metabolism by degradative enzymes in tissues and excretion through renal tubule exchange proteins. Therefore, the global profiling of the proteome, defined as the entire protein complement of the genome expressed in a particular cell or organ, or in plasma or serum at a particular time, offers the potential for identification of important biomarkers of nutritional state that respond to alterations in diet. The present review considers the published evidence of nutritional modulation of the proteome in vivo which has expanded exponentially over the last 3 years. It highlights some of the challenges faced by researchers using proteomic approaches to understand the interactions of diet with genomic and metabolic–phenotypic variables in normal populations

Oxidative stress via hydrogen peroxide and menadione does not induce the secretion of IGFBP-5 in primary rat hepatocytes

Conference abstract describing how oxidative stress via hydrogen peroxide and menadione does not induce the secretion of IGFBP-5 in primary rat hepatocytes. Presented at the 2010 annual congress of the british toxicology societ

Physiotherapists’ Perspectives on the use of Telehealth for Service Delivery to Children with Developmental Delays: A Qualitative Focus Group Study

Purpose: The purposes of the study are to (1) determine what barriers and facilitators physiotherapists perceive to using telehealth, (2) to determine willingness to use and (3) to determine perspectives on training in the use of telehealth. Method: This is a qualitative semi structured interview and focus group design. Participants were recruited from the first stage of the larger research process using purposive sampling. A semi structured guide was used to facilitate discussion of shared experiences and to allow themes to emerge from the discussion. Results: Thematic analysis was used to synthesise frequent and important themes. Ten participants took part in either a focus group (n=7) or interview (n=3). Nine main themes identified were split into barriers and facilitators. Facilitators were the right family, right child, adequate technology and space, and collaboration. Barriers were technology, time management, lack of physical touch, lack of organisational support, and work environment. Conclusion: Results suggest that physiotherapists working with children with developmental delay consider telehealth to be unsuitable to replace face-to-face therapy entirely but are willing to use it to provide follow up services to the right family and the right child. Physiotherapists in the study were positive about telehealth’s potential to improve services to children in rural areas. Physiotherapists said that specific physiotherapy training in telehealth was currently lacking

Insulin-like growth factor binding protein-5 as a biomarker for detection of early liver disease

Study identifying an Insulin-like growth factor binding protein-5 as a biomarker for detection of early liver disease presented at the annual congress of the british toxicology societ

The effects of decellularisation on the mechanical properties of bone, and subsequent recellularisation of the samples.

Regenerative medicine strategies involving decellularised extracellular matrix scaffolds are developing fast and, in particular, decellularized bone has been proposed for bone tissue engineering. This study aimed to establish decellularisation and recellularisation protocols and to measure the Young’s modulus and pore size of the decellularised trabecular bone samples. Twelve bovine cancellous proximal femur samples (7mm x 7mm x 2mm) were decellularised by six cycles of overnight incubation at 37°C using two protocols: A – 10mM Tris, 1mM EDTA, 0.1% v/v Triton X-100 and B – method A plus 0.5% w/v trypsin. Decellularisation was confirmed by the absence of DNA staining with DAPI both by detecting any DNA remaining on the bone matrix spectrofluorometrically, and by microscopic examination. Young's modulus was determined before and after incubation through compression testing at 1 mm/s up to 400N (8.16MPa). The porosity of the bone samples before and after decellularisation was measured using a mercury porosimeter. Recellularisation using HOS cells (seeded at 5x105 cells per cm2bone) progressed for up to 3 weeks in DMEM supplemented with L-ascorbic acid, β-glycerophosphate, dexamethasone, FCS, PEST, and NEAA. Bone samples were placed onto non-adherent dishes and adherent dishes. The extent of recellularisation was compared in static and dynamic culture conditions using a roller incubator set at 15 rpm to effect dynamic conditions. DAPI staining revealed that protocol B removed all measurable DNA from the bone samples (Figure 1). Decellularisation did not affect Young’s modulus (Figure 2). Pore diameters did not differ with decellularisation and were in the ideal range for cell growth. Mean ALP activity (Figure 3A) and MTT reduction (Figure 3C) was greater on the adherent surface than on non-adherent surface albeit non-significantly. There was no significant difference between static and dynamic conditions in ALP activities between 3 and 7 days (Figure 3B). Data suggests that cells proliferated more readily when samples were placed in adherent dishes (Figure 3D). This work has established appropriate protocols to make donor bone scaffolds with appropriate porosity to allow reseeding with human bone cells.These could be used to repair bone defects in recipient patients

Gross motor assessment tools for children 0-12 years of age using telehealth: a scoping review

Objective: The objective of this review was to understand the scope of evidence relating to the use of telehealth for gross motor assessment tools in children 0-12 years of age. Background: Telehealth has been widely used by physiotherapists since the start of the Covid-19 pandemic, however, little is known about the validity and reliability of using gross motor assessment tools via telehealth. Gross motor assessment tools are used by physiotherapists to understand motor function, support diagnoses of motor disorders, and plan and evaluate interventions. Qualitative research identifies a lack of confidence by physiotherapists in undertaking physical assessment via telehealth. Method: A comprehensive search was undertaken of MEDLINE, Scopus, CINAHL, Physiotherapy Evidence Database (PEDro) and OTseeker in August 2022. Grey searching was also implemented. Two independent reviewers identified articles for inclusion and critically appraised the articles. Data was analysed using a narrative review. Results: 34 studies met the inclusion criteria

The presence of ascorbate induces expression of brain derived neurotrophic factor in SH-SY5Y neuroblastoma cells after peroxide insult, which is associated with increased survival

Oxidative stress and free radical production have been implicated in Alzheimer's disease, where low levels of the antioxidant vitamin C (ascorbate) have been shown to be associated with the disease. In this study, neuroblastoma SH-SY5Y cells were treated with hydrogen peroxide in the presence of ascorbate in order to elucidate the me0chanism(s) of protection against oxidative stress afforded by ascorbate. Protein oxidation, glutathione levels, cell viability and the effects on the proteome and its oxidized counterpart were monitored. SH-SY5Y cells treated with ascorbate prior to co-incubation with peroxide showed increased viability in comparison to cells treated with peroxide alone. This dual treatment also caused an increase in protein carbonyl content and a decrease in glutathione levels within the cells. Proteins, extracted from SH-SY5Y cells that were treated with either ascorbate or peroxide alone or with ascorbate prior to peroxide, were separated by two-dimensional gel electrophoresis and analyzed for oxidation. Co-incubation for 24 hours decreased the number of oxidised proteins (e.g. acyl CoA oxidase 3) and induced brain derived neurotrophic factor (BDNF) expression. Enhanced expression of BDNF may contribute to the protective effects of ascorbate against oxidative stress in neuronal cells

Aircraft observations and model simulations of concentration and particle size distribution in the Eyjafjallajökull volcanic ash cloud

The Eyjafjallajökull volcano in Iceland emitted a cloud of ash into the atmosphere during April and May 2010. Over the UK the ash cloud was observed by the FAAM BAe-146 Atmospheric Research Aircraft which was equipped with in-situ probes measuring the concentration of volcanic ash carried by particles of varying sizes. The UK Met Office Numerical Atmospheric-dispersion Modelling Environment (NAME) has been used to simulate the evolution of the ash cloud emitted by the Eyjafjallajökull volcano during the period 4–18 May 2010. In the NAME simulations the processes controlling the evolution of the concentration and particle size distribution include sedimentation and deposition of particles, horizontal dispersion and vertical wind shear. For travel times between 24 and 72 h, a 1/t relationship describes the evolution of the concentration at the centre of the ash cloud and the particle size distribution remains fairly constant. Although NAME does not represent the effects of microphysical processes, it can capture the observed decrease in concentration with travel time in this period. This suggests that, for this eruption, microphysical processes play a small role in determining the evolution of the distal ash cloud. Quantitative comparison with observations shows that NAME can simulate the observed column-integrated mass if around 4% of the total emitted mass is assumed to be transported as far as the UK by small particles (< 30 μm diameter). NAME can also simulate the observed particle size distribution if a distal particle size distribution that contains a large fraction of < 10 μm diameter particles is used, consistent with the idea that phraetomagmatic volcanoes, such as Eyjafjallajökull, emit very fine particles